Mandibular fractures / Oral surgery courses

SEMINAR
on
Mandibular fractures
CONTENTS

⇒ HISTORY
⇒ ANATOMY
⇒ BIOMECHANICS
⇒ CLASSIFICATION
⇒ DIAGNOSIS: HISTORY , CLINICAL EXAMINATION ,
RADIOLOGIC EXAMINATION
⇒ CLINICAL FEATURES
⇒ GENERAL PRINCIPLES OF TREATMENT OF MANDIBULAR
FRACTURES
⇒ OPEN VERSUS CLOSED REDUCTION
⇒ METHODS OF IMMOBILIZATION
⇒ COMPLICATIONS
⇒ CONCLUSION
⇒ REFERENCES

INTRODUCTION
Management of trauma has always been one of the surgical subsets in
which oral and maxillofacial surgeons have excelled over the years. More
particularly, our experience with dental anatomy, head and neck physiology
and occlusion provides us with unparalleled skills for the management of
mandibular fractures.
The mandible is the second most commonly fractured part of the
maxillofacial skeleton because of its prominence and its position. The
location and pattern of fractures are determined by the mechanism of injury
and the direction of the vector of force. In addition to this, the patient’s age,
the presence of teeth and the physical properties of the causing agent also
have a direct effect on the characteristics of the resulting injury.
The goals of treatment, are to restore proper function by ensuring union
of the fractured segments and reestablishing pre-injury strength; to restore any
contour defect that might arise as a result of the injury and to prevent
infection at the fractured site. restoration of the mandibular function, in
particular, as past of the stomatognathic system must include the ability to
masticate properly, to speak normally and to allow for articular movements as
ample as before treatment. In order to achieve these goals, restoration of the
normal occlusion of the patient becomes paramount for the treating surgeon.
ANATOMY :
Mandible is the largest, heaviest and strongest bone of the face. The
normal mandible provides a normal airway and proper facial contour. A solid
movable mandible allows normal chewing, swallowing and speech. Even
though, it is a very strong structure, it is prone to injury because of its

prominent position in the facial skeleton. It is a common site of electron for
receiving intentional or unintentional violence.
The body of the mandible has got horeshoe or parabola shape. Two
rami project upward from the posterior aspect of the body. The condylar
processes of these rami articulate with the temporal bone to form the TMJ
joints. The mandible has been compared to an archery bow, which is
strongest at its center and weakest at its ends, where it often breaks.
The lower jaw is a movable body, which carries the alveolar process
and the teeth. The adult mandible is composed of a compact outer and inner
plate of cortical bone and a central portion of medullary bone (spongiosa),
whose trabeculae are distributed along the lines of maximum stress.
The lower portion of the body is heavy and thick and consist of dense
cortical bone with little spongiosa and changes very little during adult life.
The alveolar process has got lingual and buccal plate of compact but thin
bone. The body of mandible is naturally strengthened by a strong system of
buttresses which extend into the region of rami.
On the lateral surface strong external oblique ridge extends from the
body obliquely upward to the anterior border of the ramus. Medial surface is
thinner than the lateral thick compact bone. Here the myelohyoid line extends
from the area of the socket of the 3rd
molar diagonally downwards and
forwards towards the genial tubercle at the midline. Bony clin is the most
vulnerable endangered targeted area, but it is naturally strengthened by the
mental protuberances. In childhood, body of the mandible is buds of
permanent teeth, but naturally protected due to resiliency of the bone.
The ramus consists essentially of two thin plates of compact bone,
separated by a narrow portion of cancellous bone. The posterior border of the
ramus is strong and rounded.
Blood supply :

• Central blood supply through the inferior alveolar artery.
• Peripheral blood supply through the periosteum.
In case of severely atrophic mandible, there is greater dependence on
periosteal blood supply than the central supply. Therefore if open reduction is
planned, stripping of the periosteum is such that, it should be kept to a
minimum.
Nerve supply :
Damage to inferior alveolar nerve often fracture, results in the
parasthesia or anaesthesia of the lower lip on the affected side. If the nerve is
completely severed, then recovery by regeneration takes 3 to 12 months,
usually proceeded by tingling sensation, parasthesia and hyperanaesthesia of
the area. The rate of recovery depends on following:
1) Accurate approximation of the nerve ends. (proper reduction of
fragments).
2) Elimination of infection
3) Proper fixation
4) Absence of any intervening hard or soft tissue in the inferior dental
canal (muscle entrapment in the fracture line or foreign body or bone
fragments.
BIOMECHANICS :
The mandibular body is a parabola shaped curved bone composed of
external and internal cortical layers surrounding a central core of cancellous
bone. The outer cortical layer is particularly strong and gives good anchorage
for osteosynthesis devices. In the chin region the cortical bone is thickest at
the lower border, where as more posteriorly it is relatively thin. At the angle
stronger parts are found along the upper part, along the oblique line which
runs from the coronoid process to the molar region, forming a ridge cross

sections in a sub-apical region reveal on average a thickness of 2.2 – 2.4 mm
at the symphysis and in the canine regions. From the host bicuspid to 1st
molar the density increases from 2.5 to 3.4 mm. In the tooth bearing alveolar
process, the bone is of variable thickness.
Another important anatomic factor with references to fracture treatment
using internal fixation is the mandibular canal, including nemovascualr
bundle. The mandibular canal runs from the lingual of the mandible to the
mental foramen in a concave course directed upwards and forwards. The
distance between the canal and the outer cortical layer averages 4.0 mm in the
bicuspid regions increasing to 5.9 mm at the second molar. The distance
between the root apices varies from 3.4 mm (central incisor) to 6.3 mm (third
molar).
The maxillary and mandibular teeth, in occlusion form a very
sensitivity balanced system; Any displacement caused by fragments leads to
diminution of masticatory function and comfort. The main aim in fracture
treatment is therefore the restoration of normal occlusion.
Displacement of the fragments of the mandibular body is
predominantly the result of activity of muscles of mastication. From a
biomechanical point of view, the ideal method of osteosyhthesis would be to
nentralze these unfavourable forces. The mechanical characteristic of the
material used for this purpose should on one hand contain there forces and on
the other hand not be so rigid that stress shielding occurs and delays healing.
Champy et al ultimately developed the technique into a practicable
clinical method. Based on a methametical model of the mandible and taking
into account the active biting forces applied to the mandible and performing
different experimental evaluation, they were able to define the strains created
within the bone by muscular activity. Moments of flexion were found at the
upper border of the mandible, increasing progressively from the front of the

teeth to a maximum of approximately 600 N in the angles. Then are also
tortion movements between the canines, which increases in sleight towards
the middle to 1000 N.
They recommended that, behind the mental foramen only one plate
should be applied, immediately below the dental roots and above the inferior
alveolar canal. In front of the mental foramen, in order to neutralive higher
torsion forces between the canines another plate near the lower border of the
mandible is necessary in addition to the subapical plate.
Muscle attachments and displacement of fractures :
The periosteum is a most important structure in determining the
stability or otherwise of a mandibular fracture. The periosteum of the
mandible is stout and unyielding and gross displacement of fragments cannot
occur if it remains attached to the bone. Perisoteum may be stripped from the
bone ends by the extremity of the force applied, but frequently it yields to the
accumulation of blood seeping from the ruptured cancellous bone. Once the
periosteal splint has been removed displacement of the bone ends is free to
occur under the influence of the attached muscles.

Fractures at the angle of the mandible :
Fractures at the angle of the mandible are influenced by the medial
pterygoid-masseter ‘sling’ of which the medial pterygoid is the stronger
component. Fractures in this region have been classified as vertically and
horizontally favourable or unfavourable. If the vertical direction of the
fracture line favours the unopposed action of the medial pterygoid muscle, the
posterior fragment will be pulled lingually. If the horizontal direction of the
fracture line favours the unopposed action of the masseter and medial
pterygoid muscle in an upward direction, the posterior fragment will be

displaced upwards. It must be remembered that vertically and horizontally
unfavourable fractures may be undisplaced if the periosteum is undisturbed.
The concept is only important when the periosteum has been ruptured or
stripped from the bone. A favourable facture line will, however, make the
reduced fragments easier to stabilize. The presence of an erupted tooth on the
posterior fragment will sometimes prevent gross displacement of this
fragment in an upward direction if its crown impacts on the opposing upper
tooth.
Fractures at the symphysis and parasymphysis :
In the symphysis region muscle attachments are also important. The
mylohyoid muscle constitutes a diaphragm between the hyoid bone and the
mylohyoid ridge on the inner aspect of the mandible. In transverse midline

fractures of the symphysis the mylohyoid and geniohyoid muscles act as a
stabilizing force. An oblique fracture in this region will tend to overlap under
the influence of the geniohyoid/mylohyoid diaphragm.
When a bilateral parasymphyseal fracture occurs it usually results from
considerable force which disrupts the periosteum over a wide area. Such a
fracture is readily displaced posteriorly under the influence of the
genioglossus muscle and to a lesser extent the geniohyoid. It is often statd
that such a fracture removes the attachment of the tongue to the mandible and
allows the tongue to fall back and obstruct the oropharynx. This is in fact not
the case, as the tongue is still firmly attached to the hyoid bone which in turn
remains connected to the mandible by the posterior parts of the mylohyoid
muscle. In addition, the intrinsic muscles of the tongue continue to exert
control and the tongue remains forward in the oral cavity. Voluntary tongue
control is lost only when the patient’s level of consciousness is depressed and
consequently it is only in these circumstances that the detached symphysis
constitutes a threat to the airway.
Fractures of the condylar process :
When a fracture of the condylar neck occurs the condylar head is
frequently displaced and sometimes dislocates from the articular fossa. The
most frequent direction of displacement is medially and forward under the

influence of the lateral pterygoid muscle. The importance of this muscle as a
displacing force is more dramatically illustrated in those cases where
anteromedial dislocation occurs some days after injury in a previously
undisplaced fracture.
Fracture of the coronoid process :
This is a rare fracture which is said to be brought about b reflex
muscular contraction of the strong temporalis muscle which then displaces the
fragment upwards towards the infratemporal fossa.
Comminuted fractures :
Extensively comminuted fractures, such as occur following missile
injuries, may involve a considerable area of mandibular bone. Where there
are strong muscle attachments as at the ramus and angle the amount of
displacement of the comminuted segment is often remarkably little. This is
explained by the fragmentation at the site of the muscle attachments. The
small fragments are pulled away by the contracting muscle leaving the bulk of
the comminuted bone relatively undisplaced.
HISTORY OF MANDIBULAR FRACTURES :
Writings on mandibular fractures appeared as early as 1650 BC, when
Egyptian papyras described the examination, diagnosis and treatment of
mandible fractures and other surgical ailments.
Hippocrates described direct reappoximation of the fracture segments
with the use of circumdental wires, similar to today’s bridal wires. He
advocated wiring of the adjacent teeth with external bandaging to immobilize
the fracture fragments. The importance of establishing proper occlusion was
described in 1180, Salerno, Italy. In 1492, the use of maxillomandibular
fixation in the treatment of mandibular fracture was advocated 1795 Chopart

and Desault described the effects of elevator and depressor muscle on
mandibular fragments.
Through 1800s and early 1900s, several methods were used to reduce
and immobilize mandibular fractures.

HISTORY OF TREATMENT
BANDAGES AND
EXTERNAL APPLIANCES:
Bandages, first mentioned by Hippocrates, gained notoriety and
acceptance as a standard of care when John Rhe Barton described his Barton
bandage. This bandage provided posterior directional forces on the fractured
mandible, resulting in deformities such as the “bird face” and maluniouns.

Extraoral and Intraoral Appliance:
The appliance worked by placing a rigid splint on the occlusal surface
of the teeth and one on the undersurface of the mandible. A viselike device
was then used to apply pressure to the two splints, theoretically immobilizing
and fixating the fractured segments.
Gunning was the first to use a custom-fitted intraoral dental splint for
immobilization. He used the splint in conjunction with an external head
appliance. His splints could also be applied to both the maxilla and the
mandible, resulting in intermaxillary fixation. An anterior space was provided
for nourishment. This basic principle of using splints for intermaxillary
fixation, although modified, is still used routinely in the treatment of
edentulous and partially edentulous mandible fractures.
Monomaxillary wiring, Bars, Arches, and Splints:

Originally advocated by Hippocrates, then later supported in the
writings of numerous authors, monomaxillary wiring was popular in the
treatment of mandible fractures. Being similar in concept to today’s bridle
wire and to the Risdon wire of the early 1920s, monomaxillary wiring
afforded ed some element of reduction, but without supplemental fixation,
fractures were inadequately immobilized.
Splints became popular in the middle of the nineteenth century and
were usually cast of metal and custom-fitted for the patient. Splints were
fabricated with the use of models made after reduction of the fragments.
Some were cemented to lingual segments together.
The use of monomaxillary wiring, bars, arches, and splints is limited to
fractures containing stable teeth on both sides of the fracture.
Intermaxillary Wiring:
Guglielmo Salicetti (William of Saliceto) has been credited with being
the first to use intermaxillary fixation. Gilmer, also credited with being the
first to use this technique, passed wires around individual teeth of both arches
and then ligated these opposing wires.
Orthodontic bands and arches were used in patients with loose,
fractured, or missing teeth. The famous American orthodontist Angle
described many methods of intermaxillary fixation that used bands and other
orthodontic techniques.

Open Reduction and Internal Fixation:
Sutures:
In the middle of the nineteenth century, Buck and Kinlock described
the use of wire ligature for the immobilization of mandible fractures. Using
this method, one would drill a hole on both sides of the fracture site and then
pass a wire. The wire, which was iron or silver, was then tightened
periodically by creating pigtails on each end of it. This method was hampered
by a high incidence of infection.
Bone Plates:
In 1881, Gilmer described a method of mandibular fracture fixation the
used two heavy rods placed on either side of the fracture and wired together.
The rods were pushed through skin, mucous membrane, and bone and were
wired on both the mouth and the skin sides. Dorrance and Bransfield state
that the earliest reference to the use of true bone plates was that of Schede,
who, around 1888, used a solid steel plate held by four screws. During World
War I, Kazanjian used, wire sutures through bone fragments and tied the wire
to an arch bar for fixation.
Biodegradable Plates and Plating Systems:

Internal rigid fixation of the facial skeleton is a reliable method of
obtaining osteosynthesis. Historically, metallic plates and screws have been
used to allow for early passive and active function. Depending on the type
and location of the implants, it may be necessary to remove the materials at a
later time. Scher and colleagues (1988) and Merrit and Brown (1985) have
reported multiple potential problems with maintaining metallic implants in the
facial skeleton. It may become necessary to remove plates because of stress
-protection-induced osteopenia in the cortex beneath the plate, causing a
reduction in cortical thickness and shaft caliper.
The use of resorbable plates and screws has been studied for nearly 20
years. Most of the studies included polymers (e.g., poly L-lactide
polyglycolide, and polydioxanone).Bos (1989) and Rozema and associates
(1990) reported on studies in which Champy’s principles were followed and
healing was uneventful, without callus formation. They also reported that no
backscatter was seen with irradiation. Gerlach, (1988) also reported
uneventful healing, although reported healing included callus formation.
The dimensions of plates for these studies were usually large, when
compared to miniplates. This would limit their use in the maxillofacial region.
These materials have less strength, which would limit their use in loaded and
functional bone.

In the mid-1960s, Luhr pursued research in rigid fixation for the facial
skeleton and developed the Vitallium mandibular compression plate, using
glide screw principles. Throughout the 1960s. Luhr continued research on
rigid fixation and also contributed the self-threading screw. In the 1970s,
investigators, including Spiessl, studied AO/ASIF principles. They found that
adaptation of a compression plate on the lateral cortex, at the inferior border,
the superior border (tension zone) splayed. Many investigators thought a
second tension-zone plate would be necessary, others, believed that arch bars
in tooth-bearing areas were sufficient to limit the tension-zones splaying. In
1973, Schmocker and Speissl developed the eccentric dynamic compression
plate, which provided compression at the tension and compression zones of
the mandible. When the screws closest to the fracture were tightened, the
fracture line would be placed under compression. When the eccentric
terminals were tightened, the alveolar segment would be reduced.
In the early 1970s investigations were started to evaluate the use of
smaller plating systems. In 1973, Michelet and colleagues placed bendable,
monocortical miniplates to treat mandible fractures. The advantages of
miniplates were their thinness and the fact that they could be placed through
intraoral incisions.
Edentulous Mandibular Fractures :

The history of treating fractures of edentulous jaws began with a report
by Baudens (1844), who used circumferential wiring to reduce and fix the
bone. Gunning used splints, as described previously. Robert (1851) used
silver wire passed circumferentially around the mandible with a needles, and
tied the wire around a piece of lead that had been molded to the edentulous
mandible.
STATISTICS ASSOCCIATED WITH MANDIBULAR FRACTURES:
Demographic data related to mandibular fractures are difficult to
evaluate because of the many variables associated with the studies. Statistics-
related to mandibular fractures are available from countries throughout the
world. However, most are retrospective. The studies discuss maxillofacial
injures, situations that require extensive treatment. Statistics from smaller
developing countries tend to show that mandibular fractures are usually
isolated, single, nondisplaced fractures caused by assaults and treated only by
intermaxillary fixation. Study of Ellis and coworkers, vehicular accidents
accounted for only 15% of the fractures. The difference may be explained by
the environmental and social characteristics of the locality under study.

A decade later, however, the etiologic trend had changed, as shown by
Fridrich and associates in retrospective study involving the same demographic
area. They demonstrated that altercations accounted for 47% of fractures, and
automobile accidents 27%. Vetter and coworkers also commented on the
change in etiology when they mentioned that within a decade’s time the ratio
of motor vehicle accidents to interpersonal assault as the cause of mandible
fractures in creased from around 3:2 to almost 1:1.
Etiology of Mandibular Fractures:
Despite the many variables associated with the etiology of mandibular
fractures, vehicular accidents and assaults are undoubtedly the primary causes
of mandibular fractures throughout the world.
Location of Mandibular Fractures :
In the cases evaluated for fracture location, the mean percentages were
in following: body (29%), condyle (26%), angle (25%), symphysis (17%),
ramus (4%), and coronoid proces (1%). As discussed, the variables are
enormous, but certainly, as a generalization, fractures that occur in the body,
condyle, and angle do not differ much in incidence, and fractures of the ramus
and coronoid process are rare.

Individual studies demonstrate how etiology plays a role in fracture
location. Fridrich and associates showed that when fractures due to
automobile accidents were considered, the condylar region was the most
common site. When motorcycle accidents were considered, the symphysis
was the are most often affected. When assault was considered, the angle
demonstrated the highest incidence of fracture.
Facial Fractures Associated With Mandibular Fractures :
Mandibular fractures were the only facial bone fractures in fractures in
an average of 70% of the patients. The literature is generally divided
between patients with mandibular and midface fractures and those with
mandibular and “other facial bone” fractures. Of the patients reported, 15%
had another facial bone fracture, along with the fractured mandible.

Non maxillofacial Trauma Associated With Mandibular Fractures
The literature dealing with concomitant non maxillofacial injuries
associated with mandibular fractures is difficult to interpret with the wide
variation in reported injuries. In the study of Ellis and colleagues, 90% of the
patients had no other injuries, probably because the etiology was primarily
assault. olson and colleagues reported associated injuries in 46.6% of all
patients treated, most of whom were involved in vehicular accidents.
CLASSIFICATION OF MANDIBULAR FRACTURES:
1. Simple, or closed: A fracture that does not produce a wound open to the
external environment, whether it be through the skin, mucosa, or
periodontal membrane.
2. Compound or open: A fracture in which an external wound, involving
skin, mucosa, or periodontal membrane, communicates with the break in
the bone.
3. Comminuted: A fracture in which the bone is splintered or crushed.
4. Greenstick: A fracture in which one cortex of the bone is broken, the other
cortex being bent.
5. Pathologic: A fracture occurring from mild injury because of pre-existing
bone disease.

6. Multiple: A variety in which there are two or more lines of fracture on the
same bone not comunicating with one another.
7. Impacted: A fracture in which one fragment is firmly driven into the other.
8. Atrophic: A spontaneous fracture resulting from atrophy of the bone, as in
edentulous mandibles.
9. Indirect: A fracture at a point distant from the site of injury.
10.Complicated, or complex: A fracture in which there is considerable injury
to the adjacent soft tissues or adjacent parts; may be simple or compound.
Classification by Anatomic Region :
Mandibular fractures are also classified by the anatomic areas
involved. These areas are as follows: symphysis, body, angle, ramus,
condylar proces, coronoid process, and alveolar process. Dingman and
Nativig defined these regions as follows:
1. Midline : Fractures between central incisors
2. Parasymphyseal: Fractures occurring within the area of the symphsis
3. symphysis: Bounded by vertical lines distal to the canine teeth
4. Body : From the distal symphysis to a line coinciding with the alveolar
boreder of the masseter muscle (usually including the third molar)

5. Angle : Traingular region bounded by the anterior border of the masseter
muscle to-the posterosuperior attachment of the masseter muscle (usually
distal to the third molar)
6. Ramus : Bounded by the superior aspect of the angle to two lines forming
an apex at the sigmoid notch
7. Condylar Process: Area of the condylar process superior to the ramus
regions
8. Coronoid Process: Includes the coronoid process of the mandible superior
to the ramus region.
9. Alveolar Process : The region the would normally contain teeth.

Kazanjian and Converse classified mandibular fractures by the presence or
absence of serviceable teeth in relation to the line of fracture. They thought
that their classification was helpful in determining treatment. Three classes
were defined:
Class I: Teeth are present on both sides of the
fracture line.
Class II: Teeth are present on only side of the fracture line.
Class III: The patient is edentulous.
They believed that class I fractures could be treated by a variety of
techniques, using the teeth for monomaxillary or intermaxillary fixation. Class
II fractures, usually involving for monomaxillary angle or partially edentulous
body of the mandible, require intermaxillary fixation. Class III fractures
require prosthetic techniques or open reduction methods, or both, for
stabilization.
Rowe and Killey divided mandibular fractures into two classes: (1) those not
involving basal bone and (2) those invovling basal bone. The first class
primarily comprised alveolar process fractures. The second class was divided
into single unilateral, double unilateral, bilateral, and multiple.
Kruger and Schilli took into account many of the aforementioned
classifications and developed four categories of mandibular fractures:

I. Relation the External Environment
A. Simple or closed
B. Compound or open
II. Type of Fractures
A. Incomplete
B. Greenstick
C. Complete
D. Comminuted.
III. Dentition of the Jaw With Reference to the Use of Splints
A. Sufficiently dentulous jaw
B. Edentulous or insufficiently dentulous jaw
C. primary and mixed dentition
IV. Localization
A. Fractures of the symphysis region between the
canines
B. Fractures of the canine region
C. Fractures of the body of the mandible between the canine
and the angle of the mandible
D. Fractures of the angle of the mandible in the third
molar region

E. Fractures of the mandibular ramus between the
angle of the mandible and the sigmoid notch
F. Fractures of the coronoid process
G. Fractures of the condylar process.
An important classification of mandibular angle and body fractures
relates to the direction of the fracture line and the effect of muscle action on
the fractures fragments. Angle fractures may be classified as (1) vertically
favorable or unfavorable and (2) horizontally favorable or unfavorable.
In fractures of the angle of the mandible, the muscles attached to the
ramus (masseter, temporal, and medial pterygoid) displace the proximal
segment upward and medially when the fractures are vertically and
horizontally unfavorable. Conversely, these same muscles tend to impact the
bone, minimizing displacement in horizontally and vertically favorable
fractures. The farther forward the fracture occurs in the body of the mandible,
the more the upwards displacement of those muscles is counteracted by the
downward pull of the mylohyoid muscles. In bilateral fractures in the cuspid
areas, the symphysis of the mandible displaced inferiorly and posteriorly by
the pull of the digastric, geniohyoid, and genioglossus muslces.
DIAGNOSIS OF MANDIBULAR FRACTURES:
History:

A thorough history is imperative for the proper diagnosis of mandibular
fractures. The patient’s health history may reveal pre-existing systemic bone
disease, neoplasia with potential metastasis, arthritis and related collagen
disorders, nutritional and metabolic disorder, and endocrine disease that may
cause or be directly related to the fractured jaw. The history also reveals
significant medical and psychiatric problems that will influence tha
management of the patient and perhaps even dictate treatment modalities.
A history of temporomandibular joint dysfunction can have significant
legal and post-treatment ramifications.
The type and direction of traumatic force can be extremely helpful in
diagnosis. Fractures sustained in vehicular accidents are usually far different
from those sustained in personal altercations. Since the magnitude of the force
can be much great, victims of automobile and motorcycle accidents tend to
have multiple, compound, comminuted mandibular fractures, whereas the
patient hit by a fist may sustain single, simple, non displaced fractures.
The object that caused the fractures can also influence the type and
number of fractures. A blow from a broad, blunt object (2 X 4 piece of
wood) may cause several fractures (e.g., symphysis and condyle) because the
impact of the force is sustained throughout the bone, whereas a smaller, well-
defined object (hammer or pipe) may cause a single comminuted fracture,
since the impact of the force is concentrated in a smaller area.

Knowing the direction of force can help the clinician diagnose
concomitant fractures. An anterior blow directly to the chin can result in
bilateral condylar fractures, and an angled blow to the parasymphsis may
cause a contralateral condylar or angle fracture. A patient with teeth clenched
together at the moment of impact is more likely to have dental and alveolar
process fractures than moment of impact is more likely to have dental and
alveolar process fractures than basal bone fractures. Even knowing where the
patient was sitting in an automobile may aid in the diagnosis of mandibular or
other injuries. Chest injuries caused by nonecollapsible steering wheels, facial
fractures caused by striking unpadded of predictable injuries that have been
eliminated by the use of seat belts and by effective automotive safety
engineering.
Clinical Examination :
The signs and symptoms of mandibular fractures are as follows.
Change in Occlusion :

Any change in occlusion is highly suggestive of mandibular fracture.
The clinician should ask the patient whether his or her bite feels different. A
change in occlusion can result from fractured teeth, a fractured alveolar
process, a fractured mandible at any location, and trauma to the
temporomandibular joint and muscles of mastication. Post-traumatic
premature posterior dental contact or anterior open bite may result from
bilateral fractures of the mandibular condyle or angle as well as from
maxillary fractures with inferior displacement of the posterior maxilla.
Posterior open bite may occur with fractures of the anterior alveolar process
or parasymphyeal fractures. Unilateral open bite may occur owing to
ipsilateral angle and parasymphyseal fractures. Posterior crossbite can result
from midline symphyseal and condylar fractures with splaying of the posterior
mandibular segments.
Retrognathic occlusion is assocated with condylar or angle fractures
(as well as forward displaced maxillary fractures), and prognathic occlusion
can occur with effusion of the temporomandibular joints, and with protective
forward posturing of the mandible (also retro positioning of the maxilla).
These examples are only a few of the multiple occlusal disharmonies that can
exist, but any change in occlusion has to be considered the primary diagnostic
sign of mandibular fracture.
Anesthesia, Paresthesia, or Dysesthesia the Lower Lip:

Although changes in sensation in the lower lip and chin may be related
to chin and lip lacerations as well a s blunt trauma, numbness in the
distribution of the inferior alveolar nerve after trauma is almost path
gnomonic of a fracture distal to the mandibular foramen. Conversely, most
nodisplaced fractures of the mandibular angle, body, and symphsis are not
characterized by anesthesia, so the clinicians must not use lip anesthesia as
the sole feature in diagnosis.
Abnormal Mandibular Movements:

Most patient presenting with a fractured mandible have limited opening
and trismus owing to guarding of the muscle of mastication. However, certain
mandibular fractures or associated facial fractures result in predictable
abnormal mandibular movements. A classic example is deviation on opening
toward the side of a mandibular condylar fracture. Because lateral pterygoid
muscle function on the unaffected side is not counteracted on the opposite
side by the nonfunctioning lateral pterygoid muscle, deviation results.
Inllability to open the mandible may be caused by the impingement of the
coronoid process on the zygomatic arch either from fractures of the ramus
and coronoid process or from depression of a zygomatic arch fracture.
Inability to close the jaw can be the result of fractures of the alveolar process,
angle, ramus, or symphysis, causing premature dental contact. Lateral
mandibular rmovements may be inhibited by bilateral condylar fractures and
fractures of the ramus with bone displacement.
Change in Facial Contour and Mandibular Arch Form

Although facial contour may be masked by swelling, the clinicinan
should examine the face and mandible for abnormal contours. A flattened
appearance of the lateral aspect of the face may be the result of a fractured
body, angle, or ramus. A deficient mandibular angle can occur with
unfavorable angle fractures in which the proximal fragment rotates
superiorly. A retruded chin can be caused by bilateral parasymphyseal
fractures. The appearance of an elongated face may be the result of bilateral
subcondylar, angle, or body fractures, allowing the anterior mandible to be
displaced downward. Facial asymmetry should alert the clinician to the
possibility of mandibular fracture. The same holds true for mandibular arch
form. If there is a deviation from the normal U-shaped curve of the mandible,
fracture should be suspected.
Laceration, Hematoma, and Ecchymosis :

Trauma significant enough to cause loss of skin or mucosal continuity
or subcutaneous-sub mucosal bleeding certainly can result in trauma to the
underlying mandible. Lacerations should be carefully inspected prior to
closure. The direction and type of fracture may be visualized directly through
the laceration, with the clinician thus gaining diagnostic information that may
be impossible to ascertain clinically or radio graphically. The common
practice of closing facial lacerations before treatment standpoint. The
diagnostic sing of ecchymosis in the floor of the mouth indicates mandibular
body or symphyseal fracture.
Loose Teeth and Crepitation on Palpation :
A thorough examination of the teeth and supporting bone can help
diagnose alveolar process, body, and symphyseal fractures. A force strong
enough to loosen teeth certainly can fracture than underlying bone. Multiple
fractured teeth that are firm indicate that the jaws were clenched during
traumatic insult, thus lessening the effect on the supporting bone. The
clinician should palpate the mandible using both hands, with the thumb on the
teeth and the fingers on the lower border of the mandible. By slowly and
carefully placing pressure between the two hands, the clinician can detect
crepitation in a fracture. Too often, this simple diagnostic technique is
overlooked in favour of extensive (and expensive) radiologic diagnostic
methods.

Dolor, Tumor, Rubor and Color :
Pain, swelling, redness, and localized heat have been noted as signs of
inflammation since the time of the ancient Greeks. All these findings are
excellent primary sings of trauma and can greatly increase the index of
suspicion for mandibular fracture.
Radiologic Examination:
The following are types of radiologic studies that are helpful in the
diagnosis of mandibular fractures :
• Panoramic radiograph
• Lateral oblique radiograph
• Posteroanterior radiograph
• Occlusal view
• Periapical view
• Reverse Towne’s view
• Temporaomandibular joint, including tomograms
• Computed tomography (CT) scan.

The single most informative radio logic study used in diagnosing
mandibular fractures is the panoramic radiograph, showing the entire
mandible, including condyles. The advantages are simplicity of technique,
the ability to visualize the entire mandible in one radiograph, and the
generally good detail. The disadvantages are as follows; The technique
usually requires the patient to be upright (machines that allow the patient to
be prone are available), which may make it impractical in the severely
traumatized patient; it is difficult to appreciate buccal-lingual bone
displacement or medical condylar displacement; and fine detail is lacking in
the temporomandibular joint area, the symphysis region (depending on type
of equipment), and the dental and alveolar process region. A secondary but
important disadvantage is that panoramic radiographic equipment is not
present in all hospital radiology facilities.

The lateral oblique view of the mandible can be help in the diagnosis of
ramus, angle, and posterior body fracture. The technique is simple and can
be done in any radiology department. The condyle region is often unclear, as
is the bicuspid and symphysis region. The Caldwell posteroanterior view
demonstrates any medial or lateral displacement of fractures of the ramus,
angle, body and symphysis. The condylar region is not well demonstrated on
this view, but midline or symphyseal fractures can be well visualized. The
anteroposterior view is occasionally used for patients who cannot be
positioned in the supine position; however, considerable magnification and
distortion occur with this view. The mandibular occlusal view demonstrated
on this view, but midline or symphyseal fractures can be well visualized. The
anteroposterior view is occasionally used for patients who cannot be
positioned in the supine position; however, considerable magnification and
distortion occur with this view. The mandibular occlusal view demonstrates
discrepancies in the medial and lateral position of body fractures and also
shows anteroposterior displacement in the symphysis region. The reverse
Towne’s view is ideal for showing medial displacement of condyle and
condylar neck fractures. Transcranial lateral views of the temporomandibular
joint are helpful in detecting condylar fractures and anterior displacement of
the condylar head. Periapical dental films show the most detail and can be
used for nondisplaced linear fractures of the dody as well as alveolar process

and dental trauma. Plain tomograms can be used in an anteroposterior and
lateral direction when greater detail is necessary. The CT scan is ideal for
condylar fractures that are difficult to visualize; however, greater expense and
radiation exposure limit its use to cases that cannot be diagnosed with plain
films and panoramic tomography.
In summary, as with most other imaging procedures, it is usually
optimal to have views of the mandible in two planes oriented at 90 degrees to
each another.
GENERAL PRINCIPLES IN THE TREATMENT OF MANDIBULAR
FRACTURES
1. The patient’s general physical status should be carefully evaluated and
monitor prior to any consideration of treating mandibular fractures.
It must be emphasized that any force great enough to cause a fractured
mandible is capable of injuring any other organ system in the body. This fact
is obvious when dealing with massive “crush” injuries of the face with
concomitant multiple organ system involvement. However, it is all too easy
for the clinical to focus on an obvious isolated mandibular fracture without
noting a fractured cervical spine. The downward spiral to disaster can begin
by not following this principle.

Banna also reported a case and reviewed the literature on post-
traumatic thrombotic occlusion associated with an undisplaced body fracture
of the mandible became apparent 48 hours after the injury. Gordon and
colleagues described a patient with a unilateral body fracture of the mandible
who developed symptoms of a ruptured spleen 5 day after the injury and 3
days after arch bars had been placed.
2. Diagnosis and treatment of mandibular fractures should be
approached methodically not with an “emergency-type” mentality.
Patients rarely die of mandibular fractures, so the clinician has time to
carefully and thoroughly evaluate the nature and extent of mandibular injuries.
Diagnosis on the basis of the history and local physical and radio logic
examination should be expedited in an orderly, efficient manner, and
treatment should be instituted in a controlled environment and fashion. This is
not, however, to condemn prolonged, unnecessary delay, which can increase
the potential for infection and nonunion.
3. Dental injuries should be evaluated and treated concurrently
treatment of mandibular fractures.

Teeth are often injured with mandibular fractures, and although the
teeth may not have to be restored immediately, dental knowledge is vitally
important in determining which teeth can and should be maintained. (a)
Fractured teeth can become infected and jeopardize bone union; however, an
intact tooth in the line of fracture that is maintaining bone fragments can be
intact tooth in the line of fracture that is maintaining bone fragments can be
protected with antibiotic coverage. (b) A second molar on an otherwise
edentuolus posterior fracture segment should be maintained to prevent
superior displacement of the fragment in intermaxillary fixation. (c)
Mandibular cuspids are the cornerstone of occlusion and should be
maintained at all costs. (d) Some teeth are not critical to restoration and can
be removed when their prognosis is doubtful and when maintenance may
adversely affect fracture treatment. For example, a lone mandibular incisor
adds little to future bridge or partial denture construction; however, a single
molar tooth in an otherwise edentulous posterior quadrant can be critical to
dental rehabilitation. (e) Some fractured teeth cannot be salvaged no matter
how critical they may be. For example, a molar tooth may be split mesially
and distally, so reconstruction would be impossible. Maintenance of this
tooth during intermaxillary fixation may result in severe discomfort and
perhaps infection.

4. Re-establishment of occlusion is the primary goal in the
treatment of mandibular fractures.
Probably because fo the mandible’s excellent blood supply, nonunion
of mandibular fragments is rare, so it is apparent that bone fragments do not
have to be in tight approximation to heal. In addition, in most cases, facial
aesthetics will not be adversely affected by slight fragment displacement.
However, function can be seriously compromised when improper treatment
results in malocclusion. Impressive-appearing radiographic bone adaptation
should not be the primary treatment goal.
5. With multiple facial fractures, mandibular fractures should be treated
first.

The old adage “inside out and from bottom to top” applies to the
proper sequence to follow when treating facial fractures. To build a
foundation on which the facial bones can be laid, it is proper that the
mandible be reconstructed first, although with the use of rigid fixation,
deviation from this principle can be allowed. All intraoral surgery should be
done prior to any extraoral open reductions or suturing of facial lacerations.
Too often, lip and skin wounds that have been meticulously closed in an
emergency room are inadvertently, or ever necessarily, reopened during the
treatment of mandiblular fractures. Gross debridement and control of
hemorrhage should be combined with temporary measures to reapproximate
extraoral wounds, thus allowing definitive treatment to be carried out after the
intraoral procedures are completed.
6. Intermaxillary fixation time should vary according to the type,
location, number, and severity of the mandibular fractures as well as the
patient’s age and health and the method used for reduction and
immobilization.

Historically, a period of 6 weeks of intermaxillary fixation has been
used to occur. however, this time is only empirical and should vary with the
patient and the clincial situation. A simple, nondisplaced greenstick
mandibular fracture occurring in a healthy child would certainly require less
intermaxillary fixation time than multiple, grossly comminuted, compound
mandibular fractures occurring in an elderly, unhealthy patient. With the
advent of rigid fixation techniques, intermaxillary fixation may be eliminated
or maintained with light elastics for short periods.
7. Prophylactic antibiotics should be used for compound fractures.
Numerous studies in the literature demonstrate the advantages of
antibiotics in the management of compound mandibular fractures, and despite
the number of new antibiotics, penicillin remains the agent of choice.
8. Nutritional needs should be closely monitor postoperatively.
Excellent reduction and fixation techniques may fail in a patient who
has undergone significant weight loss and a catabolic nutritional status.
9. Most mandibular fractures can be treated by closed reduction.

With the current enthusiasm for open reduction and rigid fixation in the
treatment of mandibular fractures, it is important to remember that closed
reduction techniques have a long history of success. Although open
techniques have advantages, such as more exacting bone fragment
reapproximation and earlier return to function by the patient, significant
disadvantages exist as well. They may subject the patient to prolonged
anesthesia, may increase the risk of infection and metal rejection, may cause
damage to adjacent teeth and nerves, may result in lntra oral or extraoral
scarring, and may increase hospitalization time and cost.
Indications for Closed Reduction
Nondisplaced Favorable Fractues
The simplest means possible should be used to reduce and fixate
mandibular fractures. For the reasons specified previously, open reduction
can carry an in creased risk of morbidity, so if possible, closed techniques
should be use for treatment.
Grossly Comminuted Fractures

Because of the excellent blood supply to the face, small fragments of
bones will coalesce and heal if the associated periosteum is not disturbed.
Comminuted fractures should be managed as a “bag of bones”, with the
clinician utilizing closed techniques to establish normal occlusion without
violating the integrity of the vascular supply to the bone fragments.
Fractures Exposed by Significant Loss of Overlying Soft Tissues
Fracture repair is somewhat dependent on soft tissue coverage and
vascular supply. Soft tissue coverage should be established by rotational
flaps, micro vascular grafts, or (if the area is small) secondary granulation.
Wires, screws, and plates may decrease the chance of successful bone union
by further disrupting the covering soft tissue.
Edentulous Mandibular Fractures

These fractures present a special challenge because the inferior
alveolar vascular supply to the bone is severely compromised, there is little
cancellous bone (with associated osteoblastic endosteum) for repair, and the
fractures usually occur in the elderly, in whom the normal healing potential
can be retarded. Open reduction requires stripping of the covering
periosteum, which further inhibits osteogenesis. Closed reduction with the use
of mandibular prosthesis held in place by circum-mandibular wire offers a
more conservative approach. If delayed healing or nonunion occurs and open
reduction is necessary, a supplemental bone graft across the fracture site
should be considered. In severely atrophic edentulous ridges, open reduction
with primary bone grafting may be indicated, since proper alinment of the
fractured ends of bone may be impossible because of the small cross-
sectional diameter of the mandibular body.
Mandibular Fractures in Children With Developing Dentitions

Open reduction with or plates carries the risk of damage to the
developing tooth buds, which occupy a major portion of the mandible in,
children. If open reduction is necessary because of gross displacement of the
fragments, fine wires should be placed at the most inferior border of the
mandbile, engaging only the cortex Closed reduction is indicated with special
special wiring technique (continuous loop) or fabricated acrylic splints
maintained by circum-mandibular wiring. A special concern in children is
fractures of the mandibular condyle. Damage to the condylar growth center
can result in retarded growth of the mandible and facial asymmetry.
Intracapsular condylar fractures in children can also lead to ankylosis of the
joint, so early mobilization is indicated.
Coronoid Process Fractures :
Fractures of the coronoid process are rarely isolated and are usually
simple and linear with little displacement, although with extreme trauma the
bone may be displaced into the temporal fossa. Isolated fractures of the
coronoid process cause trismus and swelling in the region of the zygomatic
arch. There may be swelling in the retromolar area and a lateral crossbite.
Treatment is usually instituted only if the occlusion is compromised or if the
fractured coronoid process impinge on the zygomatic arch, inhibiting
mandibular movement.

Condylar Fractures :
Most condylar fractures can and should be treated via-clsoed
techniques if the occlusion is compromised. Early jaw mobilization and
physical therapy are indicated to prevent ankylosis or limited jaw movements.
Indications for Open Reduction
Displaced Unfavorable Fractures Through the Angle of the Mandible
Open reduction is indicated for this fracture when the proximal
fragment is displaced superiorly or medially and reduction cannot be
maintained without intraosseous wires, screws, or plating.
Displaced Unfavorable Fractures of the Body or the Parasymphyseal
Region of the Mandible
The mylohyoid, digastric, geniohyoid, and genioglossus muscles may
further displace the fragments. When treated with closed reduction,
parasympyseal fractures tend to open at the inferior border, with the superior
aspects of the mandibular segments rotating medially at the point of fixation.
With medial rotation of the body of the mandible, the lingual cusps of all
premolars and molars move out of occlusal contact. If the constriction is not
corrected, masticatory inefficiency and negative periodontal changes occur.
Multiple Fractures of the Facial Bones :

In multiple fractures of the facial bones, open fixation of the
mandibular segments provides a stable base for restoration.
Midface Fractures and Displaced Bilateral Condylar Fractures
With midface fractures and displaced bilateral condylar fractures, one
of the condylar fractures should be opened to establish the vertical dimension
of the face. If this procedure is not done, any type of suspension wiring, such
as that from th fronto zygomatic suture area to the mandible, would tend to
collapse and telescope the fractures of the midface and condyles, resulting in
a foreshortened facial appearance.
Fractures of an Edentulous Mandible With Severe Displacement of the
Fracture Fragments

In fractures of an edentulous mandible with severe displacement of the
fracture fragments, open reduction should be considered to re-establish
continuity of the mandible. The technique is especially helpful with a
nonatrophic mandible when there are no dentures, so the occlusion is not an
immediate concern. In this situation, palting of the mandible without
intermaxillary fixation should be a strong possiblity. As the mandible
becomes extremely atrophic, consideration must be given to the status of
blood supply to the bone and the effect of an open surgical procedure on the
compromised vascularity. Supplemental bone grafts have to be considered in
extremely atrophic mandibular fractures.
Edentulous Maxilla Opposing a Mandibular Fracture
When a maxilla opposing a mandibular fracture is edentoulous or
contains insufficient teeth to allow intermaxillary fixation, open reduction
should be considered. Open reduction with rigid fixation of the mandibular
fractures would eliminate the need for intermaxillary fixation, However, if
the patient’s condition warrants closed reduction, a prosthesis could be
constructed for the maxilla, it could be stabilized with palatal screws or
circumzygomatic wires, and routine intermaxillary fixation could be utilized
to treat th fractured mandible.

Delay of Tratment and Interposition of Soft Tissue Between
Noncontacting Displaced Fracture Fragments
When treatment has been delayed and soft tissue become interposed
between noncontacting displaced fracture fragments, open reduction should
be utilized. there are instances in which the treatment of mandibular fractures
is delayed because of head injury or other serious medical problems, so
withy time connective tissue grows between the bone fragments, inhibiting
osteogenesis. When treatment is finally instituted, scar tissue must be
removed, and treatment completed via an open approach.
Malunion
When a poor result is obtained after mandibular fracture treatment,
various types of osteotomies will have to be done via open surgical
approaches to correct the deficiencies.
Special Systemic Conditions Contraindicating Intermaxillary
There are situations in which mandibular functional movement is
necessary, and open rigid fixation techniques can provide that option. For
example, patients with difficult-to-control seizures, psychiatric or neurologic
problems, compromised pulmonary function, and eating or gastrointestinal
disorders could benefit from open rigid fixation techniques.

TREATMENT OF MANDIBULAR FRACTURES
The foregoing classification is intended to be of assistance in
distinguish the different patterns of fracture and understanding the causes of
displacement. However, on a practical basis, mandibular fractures may be
treated by one or more of the following basic methods.
CLOSED REDUCTION AND INDIRECT SKELETAL FIXATION :
1. Direct interdental wiring
2. Indirect interdental wiring (eyelet or Ivy loop)
3. Continuous or multiple loop wiring
4. Arch bars
5. Cap splints
6. Gunning type splints
7. Pin fixation.
OPEN REDUCTION AND DIRECT SKELETAL FIXATION :
1. Transosseous wiring (osteosynthesis)
2. Plating
3. Intramedullary pinning
4. Titanium mesh
5. Circumferential straps

6. Bone clamps
7. Bone staples and Bone screws.
In recent years there has been a progressive move away from the
traditional use of predominantly closed or semiclosed indirect procedures in
the management of facial fractures towards a greater use of direct fixation
techniques.
CLOSED REDUCTION AND INDIRECT SKELETAL FIXATION :
1. Direct Interdental Wiring :
This technique provides a simple and rapid method of immobilisation
of the jaws. However, the wires tend to loosen and a broken wire cannot be
replaced without first removing and then replacing all of the others.
2. Interdental Eyelet Wiring (IVY Loop Method) :
When the teeth of a fractured jaw are fixed in the correct occlusion, the
bone fragments supporting them will, in most cases, also be satisfactorily
reduced.

Provided that teeth of a suitable number, shape and quality are present
on each fragment, eyelet wiring is a simple and effective method of reduction
and immobilization of such jaw fractures, and may control an edentulous
posterior fragment if the fracture lines are favourable and displacement
minimal. Alternative techniques, such as upper or lower border transosseous
wiring, will be required if this is not the case.
Eyelet wires may also be used in combination with Gunning-type
splints in an opposing edentulous jaw, and arch bars or cap splints in a
partially dentate jaw. Fractures of the ascending ramus or mandibular
condyle will not necessarily be reduced by this method nor will they be
completley immobilised.
BUTTON WIRING :
Leonard (1977) considers that eyelet wires have several drawbacks.
• The simple eyelet was frequently drawn into the interdental space, making
it difficult to use.
• Elastic traction using eyelets, though possible, was time consuming to
apply.
Leonard described the use of titanium buttons of 8mm diameter,
inclusive of a 1mm rim, and 2mm deep.
3) Continuous or Multiple Loop Wiring :

Stout (1943) described a technique which permits blocks of tooth in
either jaw to be wired in such a manner that elastic traction can be used to
reduce the fracture.
THE USE OF PARTIAL DENTURES :
If the patient wears a partial denture and this is available, it can be used
not only to restore the occlusion but also as a point of anchorage for the wires
or elastic bands to reinforce the intermaxillary fixation.
4) Arch Bars :
Basically there are two varieties of arch bars, those that are
commercially produced and those which are individually made for a given
patient.
Barker (1986) described a precast arch bar for greater accuracy of
occlusal reduction.
Indications for use :
1. When insufficient teeth remain to allow efficient eyelet wiring.
2. When the teeth present are so distributed that efficient intermaxillary
fixation is otherwise impossible.
3. When there are simple dentoalveolar fractures, or where multiple
toothbearing fragments in either jaw require reduction into an arch form
before intermaxillary fixation is applied.

4. As an integral part of internal skeletal suspension in the treatment of
fractures involving the middle third of the facial skeleton; alternatively,
when external skeletal fixation is indicated, an anterior projection bar may
be attached to an individually made arch bar.
5. Where laboratory and technical facilities are inadequate or non-existent.
6. To reduce the preoperative time which would otherwise be required for
cap splint preparation.
Arch bars may be necessary in both jaws, or there may be sufficient
teeth in one jaw for eyelet wiring whilst an arch bar is used in the other. The
technique will not control separate edentulous fragments but may be used in
conjunction with other techniques.
5) Cap Splints :
Cast-Silver Cap Splints :

Provided that an experienced maxillofacial technician and the
necessary laboratory facilities and time are available, cap splints are of great
assistance with fractures where standing teeth are present on one or all of the
separate fragments. Although arch bars are immediately available, fitting
them may considerably increase the operatingt ime and, as with eyelet wiring,
buccolingual rotation is not prevented. Furthermore, during the period of
immobilization, superficial dental caries may occur where there is plaque
concentration. When combined with elastic traction, cap splints may obviate
the need for a general anesthetic.
Acrylic splints :
Acrylic resin cap splints are easily and more cheaply fabricated. They
are particularly useful for the treatment of dislocated teeth and alveolar
segmental fractures.
Impressions :
Problems may be encountered in obtaining satisfactory impression
because of :
1. a) Trismus resulting from muscle spasm

b) Gagging of the posterior teeth which result either form
the upward and medial movement of the posterior
mandibular fragment, or from a posterior and downward
movement of the upper jaw resulting from a middle third fracture.
2. Soft tissue injuries, burns or edema, especially in relation to
the lips. Lacerations of the tongue and adjacent soft tissues or hemorrhage
from the fractures may produce blood clot and/or sufficient swelling to
obscure much of the crowns of the posterior teeth.
3. Dental injuries: fractures of the teeth, with or without exposed
pulps, or loose teeth may cause pain and contribute to a lock of patient
cooperation, especially in chi8ldre.
4. Cerebral irritation, alcoholism, drug addiction and apprehension also
produce special problems.
Impression technique :

After the clinical and radiographic examination has determined the
location of the fractures, and the position and condition of the teeth on the
various fragments, the disposable trays are prepared. Blood clot and debris
should be removed from the mouth using gauze moistened in sodium
bicarbonate solution and, where necessary, exposed dental pulps should be
covered by sedative dressings. Impression are taken of each separate tooth
bearing fragment if it is impossible to obtain a satisfactory impression of all
the teeth in the jaw in one tray. Any impression which loses its attachment to
the tray should be repeated; however irritating this may be otherwise the
splints will not fit correctly.
Splint dressings :
The splint dressing and positioning of the hooks depends upon the
overjet and overbite and the need or otherwise for extremely fixation.
Approximately three hooks are required on each quadrant unless an
alternative anchorage of the tie wires is proposed, such as the locking plate or
the connecting bar. The hooks should be positioned to allow the cross bracing
in a zigzag pattern of the tie wires or elastic bands. If internal suspension is
required, a loop or a reversed hook is sited on the buccal aspect of the upper
splint in the first molar region.
Preoperative procedures:

When possible, splints should be cemented on to the teeth an hour or
two before the operation so that the material can mature and harder, before
any stress is put upon it.

Cement media :
1.Black copper cement :
Provided that the teeth are dry and the cement is correctly mixed,
copper cement is the best long-term medium to use. The phosphoric acid
etches the surface of the enamel, thereby achieving a good bond and is, in
itself, bactericidal. Unfortunately the superficial enamel will be stained
temporarily and synthetic restorations permanently. Porcelain crown should
be protected by a thin smear of Vaseline to prevent cement from adhering to
them. The patient’s lips and , if present, moustache and beard should be
liberally coated with Vaseline.
It is advisable for the operator to wear surgeon’s gloves. If the fine
black powder and the acid fluid penetrate under the nails and into any
scratches or cuts they are difficult to remove.

The optimal working time for the cement is only 20-30 seconds. This
calls for extreme efficiency and, particularly in warm climates, a chilled
mixing slab to retard the setting time. The slab should be immersed in iced
water or placed in a refrigerator before use. An excess of cement must be
prepared each time so that all of the fitting surfaces of the splint are covered
by one mix. The powder is added to the fluid in small quantities and mixed by
rapid circular motions of the spatula until a light oily consistency is achieved.
Watery cement drips everywhere and thick cement will set before the splint
safe seated. The situation calls for considerable manual dexterity and a little
experience or guidance. Small splints may be difficult to manipulate and their
placement is facilitated by the attachment of `orange sticks’ to the occlusal
surface using beeswax. Once the splint is positioned, these stick’s are easily
removed so that digital pressure can be applied to the splint to seat it
properly.
The phosphoric acid solution is a strong irritant and some patients
develop a considerable edema where the cement has come into contact with
the mucous membrane. Care should, therefore, be exercised to prevent this.
2. Cold-cure acrylic :

The working time for this material is much longer. Splint retention is
achieved by the mechanical effect of the acrylic flowing into undercuts
around the teeth. No cement/tooth bond is achieved, however, so that oral
fluids will permeate into the interdental spaces and over the cervical margins
of the teeth and superficial carious lesions can occur. If the patient do not
complain of a fetor oris and foul tat during the period of splint wear, they
certainly do for a short time after removal of the splint. Commonly, local
areas of periodontal infection are found, usually associated with excess
acrylic. These, however, clear in a few day without any permanent sequelae.
3.Polycarboxylate cement :
This group of cements is considered by some surgeons to be cleaner
than the copper cements. However, they suffer from one important
disadvantage in that they do not etch the surface of the enamel and hence lack
the adhesion achieved by copper cement.
Cementing the splint:
When possible this should be done on the dental chair with good,
illumination and compressed air available. If the patient is bedridden, mobile
dental units are invaluable.
Reduction of the fracture:

Multiple fractures are more common in the lower jaw than the upper. A
sectional splint does not possess the retentive properties of a complete unit
and it is easy to dislodge it, even after the cement has completely hardened,
when manipulating the fragments, when tightening tie wires or during periods
of post anaesthetic nausea.
Postoperative care:
When the patient’s general condition permits and the edema has
subsided, the elastic bands, which become soggy, foul smelling and dirty, are
replaced by tie wires. Patients should be instructed about oral hygiene at the
earliest possible stage so that they can relieve the nursing staff of the task of
thorough oral lavage as has already been described. The cap splints rapidly
tarnish if oral hygiene is not satisfactory whereas, with reasonable care, the
labiobuccal aspect of the splints will retain their bright polished appearance.
Hooks causing soft tissue trauma must be turned inwards, loose screws
tightened and broken wires or elastics replaced. The sharp edges of splints,
screws or locking plates, or areas of dissimilar metals which cause
electrolytic ulceration in the first 2 or 3 days should be covered by softened
pink wax or gutta-percha. Wire twists which have not been bent sufficiently,
and therefore traumatize the soft tissue or catch the toothbrush, require
adjustment.

Occasionally, a splint will become loose. This is of little consequence
if it is retained by circumferential wiring. If not, and the stability of the
fractures is not controlled by the remaining splints, it must be replaced after
all the tie wires have been removed.
Splint removal :
Provided the splint is not too thick, an upper premolar pattern dental
extraction forceps, aligned parallel to the occlusal plane, is used with one
blade on the occlusal surface and the other on the cervical margin of the
splint. A slow outward rotation of the forceps will usually break the bond
between cement and the splint in that are. This rotation is repeated elsewhere
around the mouth as required until the splint can be lifted off.
Fractures of the edentulous mandible:
GUNNING-TYPE SPLINTS:
Intraoral control is achieved by `Gunning-type’ splints, retained by
peralveolar and circumferential wiring or, occasionally, other methods. It is,
therefore, a form of indirect, control of the bone fragments, transmitted
through the mucoperiosteum.
Indications :
For the reduction, fixation and immobilization of unilateral and
bilateral fractures of the edentulous mandible, where the fractures lying
proximal to these areas can be controlled by intermaxillary fixation.

Contraindications:
Unfavourably displaced fractures lying outside the denturebearing
areas, or severe posterior displacement of fractures of the anterior part of the
mandible which will probably be inadequately controlled by this method
alone and will require additional fixation, e.g. transosseous wiring.
Projectile injuries, involving grossly comminuted soft tissue and bone
loss, may not be suitable for this technique unless posterior displacement
can be prevented, although open reduction is facilitated by the lacerations.
Provided that the wound edges are correctly approximated without
inversion and excess pressure is not applied, creations of the mucous
membrane will heal normally under the gutta-percha lining of the splints.
Extreme atrophy of the maxillae or mandible complicates this
technique. In the maxilla, per alveolar wires may cut out or be impossible to
insert. However, piriform apperture, per nasal or circumzygomatic wires are
suitable alternatives.
Splint technique:
Gunning splints may be constructed from :
• The patient’s existing dentures suitably modified. These are often left at
the scent of the accident. They should be searched for and, even if broken,
can be repaired before use. Many edentulous patients have a usable
discarded set of dentures at home.

• Impressions from the patient’s mouth
• Models cast from the fitting surface of the patient’s dentures
• Prefabricated Gunning-type splints
• Disposable, edentulous impression trays without their handles.
The patient’s dentures:
Since these are likely to have a reasonable vertical dimension and
occlusion, they are generally suitable for use. The incisors and canine teeth
are removed from each denture together with the majority of the palate from
the upper denture. Two or three hooks in each quadrant are embedded with
cold-cure acrylic in the labiobuccal sufaces of both dentures.
Alternatively, groove of the appropriate width and depth is cut into the
buccal flange of each denture into which a length of Erich arch bar is secured
by quick-curing acrylic.
The depth of the flange periphery is reduced to allow for postoperative
edema and, after being roughened, the fitting surfaces are lined with softened
gutta-percha. Small grooves may by cut on the occlusal surfaces of the
denture to accommodate the per alveolar and circumferential wires.
Imperssions from the mouth:

As these reproduce any fracture displacement and soft tissue damage
of the alveolus, the technician will need to correct major misalignment of the
bone after sectioning the models. Any minor discrepancy remaining will be
compensated by the gutta-percha lining. Unless a suitable record of the
vertical dimension and jaw relationship can be taken from the patient,
provision for this is made at the time of operation by creating a trough on the
occlusal surface of the acrylic blocks which occupy the molar areas of the
lower splint. The maxillary blocks are ridged or grooved so that, when
opposed after reduction of the fracture these fit into the softened gutta-
percha.
Models cast from the fitting surfaces of the dentures:
If fracture displacement is minimal and the dentures are of recent
construction, `Gunning-type’ splints can be made from models cast from their
fitting surfaces after the elimination of any undercuts.
Prefabricated Gunning type splints:
There are several varieties of `Gunning-type’ splints but these should
combine the following properties if they are to be useful:
a. There must be separate splints for each jaw which enable immobilization
to be achieved in the correct relationship by means of hooks processed
into the outer aspect.

b. The splints must be lined with guttapercha or other suitable materials such
as soft acrylic or other polymers to prevent the ulceration which can
occur, even if the patients own dentures are used for immobilization.
c. There must be space anteriorly for feeding and breathing purposes.
Adaptation of old splints:
In an extreme urgency, previously used splints may be used provided
they are big enough and their fitting surfaces are thickly lined with gutta
percha to compensate for the discrepancies of the recipient mouth.
Disposable trays:
Under similar circumstances, after removal of the handles, these may
be lined with gutta percha, the jaw relationship being obtained by the use of
blocks of gutta percha placed in the buccal quadrants and allowed to harden
in situ. These splints are held in the mouth by the usual circumferential or per
alveolar wires, additional support being obtained if required from internal
skeletal suspension.
Circumferential wiring:
At this stage of the operation, the circumferential wires must be passed.
IF this procedure is carried out after the definitive reinsertion of the
mandibular splints, manipulation of the wires will result in displacement of
the bone ends. For this reason, the following sequence should be followed.

The point of a long curved awl is now placed externally in the desired
position inferior to the lower border of the mandible, where it will remain
remote from the fracture sites and will avoid injury to both the facial artery
and the area of the mental foramen. The operators middle or index finger of
the other hand lies in the lingual sulcus where it protects the submandibular
duct and lingual nerve and facilitates, by proprioception, the correct passage
of the instrument. The awl is then pushed through the skin until it reaches the
lower border of the mandible. With the point remaining in contact with the
bone throughout the procedure, the awl is advanced so that it emerges in
withdrawn so that the point can traverse the lower border of the mandible and
be pushed into the buccal sulcus, where the end of the wire is retrieved and
detached. At least two such wires should be inserted, their positioning
depending upon that of the fracture lines. The wire ends, secured by artery
forceps, are pulled to and fro until the bone is contacted to ensure that no soft
tissue remains between the wire and the bone. This procedure work-hardens
that portion of wire in contact with the bone. It is necessary, therefore, to
carry out this maneuver at one end of the wire before advancing it to the other
end. The work-hardened action is cut off and the artery forceps is reapplied.
The lingual ends are allowed to hang outside the mouth. In this way, free
access is provided for the next stage, which is reinsertion of the lower splint.
7. PIN FIXATION:

This technique was introduced during the Second World war for use
with compound, comminuted and frequently infected jaw fractures as a means
of controlling the fragments remote from the affected areas. Modern
antibiotics and improved surgical technique have reduced the need for pin
fixation but this method is still a valuable part of the armamentarium required
for the treatment of jaw fractures. The concept has been updated by the `box
frame’ method which was initially developed by Fordyce for the treatment of
middle third fractures of the facial skeleton. It is now of great assistance in
other problems of fixation involving the control of edentulous fragments when
a bone graft is required. Pin fixation is of particular value in the control of
bilateral edentulous posterior fragments, especially when the remainder of the
mandible has been lost and is to be replaced with a bone graft.
Advantages of pins:
a) Control of the edentulous fragments without involving the fracture
lines.
b) Can be applied under local analgesia if indicated.
c) Reduction or avoidance of the need for surgery at the fracture site,
thereby retaining the periosteal blood supply of the edentulous mandible.
d) Elimination of laboratory facilities, with minimum operative time
required.
e) Light, portable apparatus requiring only a simple surgical technique.

f) Simultaneous treatment of middle third and mandibular fractures by
relatively simple combined techniques.
g) Immobilization of the mandible may be less prolonged or even
avoided. The oral cavity is left free of apparatus, thus assisting feeding and
minimizing the risk of pulmonary complications.
Disadvantages of pins:
a) Conspicuous in daily life and uncomfortable while sleeping because
of the projection of the pins which may easily be knocked
b) Readily accessible to an interfering, uncooperative or cerebrally
irritated patient.
c) The universal joints may require frequent tightening, since
torsional forces may not be adequately controlled by this means.
d) Difficulty with washing and shaving.
e) Soft tissue scars are caused by the pinholes and there is a
constant, although slight, risk of infection.
Indications for use:
a) Pathologic fractures of gunshot injuries associated with gross bone loss,
particularly when laboratory and operating facilities are limited and
immediate control of the fragments is indicated.
b) Osteomyelitis an edentulous fractures site.

c) Fractures associated with extreme atrophy of the edentulous jaw.
d) Bone grafting of the mandible when there has been extensive bone loss.
e) Fractures of the mandible associated with fractures of the middle third of
the facial skeleton when a rapid and relatively simple fixation is indicated.
f) Gross comminution and posterior displacement of the symphysis of the
mandible in an edentulous patient.
General principles:
Two pins, joined to each other by a transverse rod and two universal
joints, are inserted into the principal anterior and posterior fragments of the
jaw. Each pin assembly is then united by a further rod or rods held by
universal joints attached to the transverse bars. If jaw immobilization is
considered necessary and is not going to be provided intraorally, use may be
made of a `box frame’, a Levant frame, a `head frame, or even a plaster of
Paris head cap if these more sophisticated craniofacial fixations are not
available. The pin fixation assembly in such cases is connected to this
apparatus by further vertical rods and universal joints.
Several varieties of pins and universal joints are available. Generally,
pins are 7 cm, long and 3mm wide, the length being sufficient to compensate
for severe edema whilst the width of the pain provides adequate strength. One
end of the pin is tapered obliquely to fit an Archimedean drill or hand

introducer, whilst the other is threaded and may have a cutting edge. Pins are
constructed from inert metals to prevent local osteitis which could otherwise
result from electrolytic action. Each operator usually prefers one of the
several varieties of pin available, some of which included:
a) Clouston-Walker pin-combines a spear point with a fine thread of
approximately 15 turns per cm
b) The East Grinstead pattern
c) The MacGregor pin is trochar-pointed with a shoulder formed by reducing
the diameter of the portion inserted into the bone to 2mm. Pins are
available in three sizes of 8mm, 10mm and 16mm as measured from the
point to the shoulder.
d) Moule pins are coarse threaded, tapered screw pins of different lengths
designed to be inserted by hand into a hole drilled by a 3 mm twist drill.
e) Toller pin constructed from titanium.
Several type of universal joints exits, constructed of various metals.
Because of the hazards incurred by using dissimilar metals in the pins,
universal joints and connecting pins, it is advisable to use joints made from
Tufnol, which act as insulators to break the circuit and thus prevent
electrolytic action.
Several orthopaedic hand drills are available, including an
Archimedean drill, Lane’s or a Swedish pattern bevel action drill, modified by

Toller to produce a 1:1 ratio. The latter is helpful, for it turns slowly and gives
the operator a clear idea of the depth of penetration of the drill point.
Operative technique:
Landmarks may be difficult to locate because of soft tissue edema. If
this is severe, it is advisable for the operator to palpate the mandible
intraorally while he marks its periphery on the surface with a skin pen.
Radiographs will indicate the position and angulations of the fracture, which
is then drawn upon the skin and this gives an approximate guide to the
position of the inferior dental nerve. The amount of forward movement of the
posterior fragments should be carefully assessed. After this initial stage it is
essential to change gloves before proceeding.
The skin must be thoroughly prepared before surgery. It is helpful for
the fingers of one hand of the assistant to be placed within the mouth in order
to support the fragments, whilst the other hand supports the symphysis.
The following description applies to Moule pins which have been
found extremely satisfactory in use.
The posterior pins are first inserted into the area of the angle of the
mandible while the skin is pushed upwards and forwards by the surgeon to
restore the relationship between the displaced bone and undisplaced soft
tissues. The lower and posterior border of the angle of the mandible is

defined by palpation and a horizontal stab incision at the proposed site of pin
insertion is made with a No.15 scalpel blade.
As in the case of a carpenter inserting a screw into wood, so it is
necessary to drill a pilot hole before inserting the pin so as to avoid the risk of
splitting the bone. The diameter of the hole must be correctly matched to that
of the pin to ensure that the threads grip the bone with maximum retention.
The tissues are bluntly dissected with the tips of a hemostat down to the
surface of the bone and Moule’s tubular soft tissue retractor is inserted.
A twist drill of 2.25 mm (3/32”) diameter is inserted into the chuck of
the drill and pushed down until the point comes into contact with the bone.
The drill point is moved about with its point in contact with the bone until the
operator is convinced of its position relative to the lower border and the angle
of the jaw. Having located a positioned approximately 1 cm from the angle,
the drill is positioned at right angles to the surface of the mandible and
drilling is commenced until the cortex is engaged. It is easy for the drill point
to slip and, to prevent this, drilling is continued in this manner but the
angulations is altered to 70° once the drill starts to penetrate. This is
continued, without any oscillation around the long axis of the drill, until the
inner cortex is just perforated. The revolutions of the drill must be slow
enough to allow the heat generated to dissipate, which is assisted by saline
being continuously applied to the drill shafts. Only light pressure should be

exerted, to avoid sudden uncontrolled penetration of the inner plate, in view
of the proximity of adjacent vital structures.
The tubular soft tissue retractor or drill sleeve must be held securely
against the bone by the assistant while the drill is withdrawn. The Mould pin
is then inserted into the turnkey and the tip engaged in the drill hole. It may
be necessary to search for this if the soft tissue has moved slightly, and the
operator should be able to discern when the point catches the rim of the hole.
The original 70° angulation must be maintained and two or three revolutions
of the hand-operated turnkey will usually convince the operator as to whether
the pin is correctly orientated. The pin is screwed in until it is tight, but
caution should be exercised when the ramus is thin and atrophic to avoid over
penetration.
In locating the position for the second pin, the operator must assess the
soft tissue edema and the need to prevent the points of the pin shafts must not
be too far apart, but sufficiently so to accommodate a universal joint on each
shaft with a further one placed between them. The hole is drilled in
converging direction to the first pin and the pin is inserted.
Pairs of holes are then drilled in the distal fragment. The fractures may
be oblique, with a surrounding haematoma which could become infected, so it
is essential to make a careful assessment from the radiographs and to place
the nearest pin at least 2-3 cm away from the fracture line. With multiple

fractures it is important to prevent posterior collapse of the symphysis, and
more than two pairs of pins may be required. Great care must be taken to
avoid the inferior dental bundle, especially in the atrophic edentulous case,
and to prevent the drill from slipping under the lower border of the mandible.
Very occasionally, screwing pins too tightly into an atrophic mandible will
result in a split in the bone which joins the two holes.
It is easy to displace or traumatize the skin when inserting pins. This
will result in skin necrosis, which continues if pressure of the skin against the
pin is allowed to persist and results in unsightly scarring,. Care is, therefore,
required to prevent skin distortion by inserting the pin to compensate for the
final position of the underlying bony fragments after reduction of the
fractures. Should some slight heaping up of the skin against the shaft persist
after insertion, a minimal stab incision should be made to relieve the tension
and allow the skin to adapt itself around the pin.
THE PIN SITES :
The entry sites may be covered by a dressing such as tulle or,
preferably, by 1.25 cm wide ribbon gauze soaked in Whitehead’s varnish
(Pigmentum Iodoform Compound) and then squeeze-dried and wrapped in a
figure-of-eight pattern around the base of the shaft. These dressings require
renewal or repositioning when the entry wound becomes exposed as the o
edema subsides. Although hey may be disturbed by the patient, the enry

wound and the underlying bone are rarely the caouse of troulbe Slight bone
infection may occur, but as the discharge drains away down the pin shaft
there is a minimum of symptoms. Surrounding whiskers must be cut by
scissors, although normal shaving is permissible in those areas to which the
patient ahs access.
Despite smoothing, the ends of the metal rods will still be prominent.
They may cause damage or injury or catch in materials but can be protected
by commercially made acrylic covers or by short lengths of polythene or
rubber tubing which is quite adequate.
COMPLICATIONS OF PIN FIXATION:
a) Anesthesia of the lip commonly results from the initial fracture. Insertion
of the pin into the inferior dental cancal will cause additional damage to
the vessels and lessen the chances of nerve regeneration. Severe pain may
result of the pin damages the nerve proximal to the fracture.
b) Involvement of the fracture line or its surrounding haematoma by incorrect
positioning of the pin may allow the entry of infection into the area.
c) Pin insertion into an oblique fracture line will cause a widening of the
fracture and the displacement of the lingula cortex despite the counter
pressure of an assistant. The looseness of the pin so positioned requires its
immediate resisting further away from the fracture.

d) Some areas of the ascending ramus are extremely thin and over
penetration may occur. This usually does not matter, since the tip lies in
the substance of the medial pterygoid muscle and no major vessel is in
close proximity. Over penetration rarely occurs with a Moule pin and is
less likely to occur with other varieties if the operator counts the
revolutions of drill with a known ration as the pins are inserted.
e) Damage to adjacent structures. The facial nerve and vessels are safe
unless a stab incision is carried too deeply because the pins will tend to
displace these structures rather than penetrate them.
The uncontrolled pin slipping beneath the lower border of the mandible
or behind its posterior border constitute a hazard to major vessels. Pressure
upon the drill should be increased slowly with the angulations of the pin kept
at right angles to the bone until penetration of the outer cortex has occurred.
Drills must be sharp so that excessive pressure is not required.
f) Jaw movement will ultimately loosen the pins. While minimal
movement appears to be beneficial in the late to malunion or infection.
It is, therefore, sometimes advisable to immobilize the jaw for at least 3
weeks, or longer if necessary, before relying entirely on pin
fixation for support of the fracture. If intermaxillary fixation by
`Gunning-type’ splints in not possible, craniofacial fixation must be used.

g) It is easy for the patient to strike objects or other people with the
ends of the pins and connecting bars. Most patients adopt a pattern of
behavior to prevent this.
h) If acute infection develops around a pin and cannot be controlled
by antibiotics, it is advisable to remove the affected pin, relying on the
remaining one which may not be involved in the hope that sufficient
organization a the fracture site will have taken place. Leakage of
parotid secretion does occasionally occur in the early days after the insertion
of pin. In most cases this cease spontaneously before the pin removal and the
fistula will usually repair itself once the pin has been removed.
PERSISTENCE OF INFECTION FOLLOWING REMOVAL:
Rarely, purulent discharge may continue following the removal of the
pin. This denotes the presence of a sequestering, sometimes in the form of a
ring, which has resulted either from overheating during the insertion of the pin
or a subsequent electrolytic reaction. If the discharge does not clear
spontaneously within a week the area should be curetted using regional block
analgesia or general anesthetic.
Treatment of mandibular fractures with teeth in one jaw only A
number of patients present with facial fractures and other injuries which do
not lend themselves to the sole use of the basic techniques previously
described.

1. The edentulous maxilla with an adequate number of suitable
mandibular teeth
It the upper denture is available and in one piece, hooks are set into the
buccal and labial aspect in cold-cure acrylic. The plate is either removed
extensively as previously mentioned or holes 1 cm in diameter are cut in the
palte for the passage of per alveolar wires. Undercuts shoul be removed from
the fitting surface of the denture, which can then be relining in situ with a
tissue conditioner, thus preventing the development of chronic moniliasis.
Gutta-percha is the alternative. If a denture is not available, `Gunning-type’
splints must be constructed. The splint or denture is wired in by per alveloar
or piriform aperture wires, whilst the mandibular fractures are reduced and
fixed.
2. Loss of maxillary bone :
Standing lower teeth predispose to increased alveolar resorption in the
opposing area of the edentulous upper jaw. Generalized atrophy of the
maxilla is not uncommon in the elderly. The anterior area of the upper jaw
may be extensively comminuted and, if any teeth are still present, they may
be fractured and require extraction. Either of these situations will render

retention from per alveolar wire, ineffective. Although some mandibular
fractures may be satisfactorily treated in such circumstances without jaw
immobilization, e.g., by cap splints or arch bars, the majority of patients will
have less discomfort and improved cahbes of bony union if jaw
immobilization is provided. Under the circumstances, the alternative mehtods
of upper splint retentiona are :
a) Bone screws or a shot length of : Kirschner wire may be inserted in
suitable undamaged areas through holes in the peripheral flanges or palate of
the denture.
b) Pinform aperture wires: Even in the elderly, the lateral aspect of the
nasal aperture affords better retention than the surrounding bone. The nasal
aperture is exposed through a mucoperiosteal incision and the periosteum and
nasal mucosa is elevated from the area. The nasal mucosa is protected by the
insertion of a Howarth’s nasal periosteal elevator. The wires are inserted as
follows:
i) A hole is drilled through the thickest part of the bone down on to the
elevator and a. 0.5 mm soft stainless steel wire is passed and brought out
through the pirifrorm aperture into the mouth. Both ends may then be twisted
around hooks processed into the upper splint or a hook in the lower splint.
Preferably, the wires should be twisted together to from a loop. A separate
wire can than be passed through the loop and attached to apparatus in either

the upper or the lower jaw or to a circumferential wire which is passed
around the lower jaw. This has the advantage of allowing the jaws to be
mobilized later without risking the fracture of either the circumferential or
piriform aperture wires.
ii) Occasionally piriform aperture wires cut out, particularly in the elderly.
Improved distribution of the wire loading is obtained by passing one end of
the wire back through the alveolus into the plate bt a straight wire introducer.
This wire is then brought forwards and twisted with the other end over the
splint.
iii) Circumpalatal wiring may be use. The palate of the maxillary splint
should not be cut away and should incorporate a wire loop at the posterior
border in the midline. A long curved awl is passed along the floor of the nose,
above the mucosa, to the region along the floor of the nose, attached to the
posterior border of the hard plate. The handle is then elevated, causing the
point to penetrate the tissues and emerge in the mouth. A 10 cm length of 0.5
mm diameter soft stainless steel wire is passed through the loop processed
into the posterior border and bent back on itself to form two 5 cm lengths.
The ends of these are passed through the eye at the tip of the awl which is
then withdrawn to pull the wire ends forwards.
A finger placed in the labial sulcus palpates the anterior limit of the
nasal fossa and the tip of the introducer is then passed inferiorly to emerge in

the labial sulcus. The wire is then detached and the introducer withdrawn.
The double length of wire now runs from the loop on the posterior edge of the
splint along the floor of the nose and down into the labial sulcus. The two
ends are then twisted been encountered. Removal is accomplished very easily
by cutting the wire where it passes through the palatal loop and pulling both
strands forwards into the labial sulcus.
c) Circumzygomatic or frontal suspension wires:
The former may be used with intact zygomatic arches and the latter
when the zygomatic complex is fractured but the angular process and
supraorbital ridges are intact. The wires may be attached to either the upper
or lower jaw fixation but preferably they should be formed into a terminal
loop which is attached to the apparatuses by a separate wire. This allows the
jaw to be mobilized without untwisting the internal suspension wire and
risking its fracture.
d) Extra skeletal retention :
This may be achieved by fixation of either jaw to the cranium
employing a `halo’ frame (Royal Berkshire Hospital Pattem Downs Surgical
Ltd), supraorbital bone pins, zygomatic bone pains or a plaster of Paris head
cap. By comparison with this alternative’s the plaster head cap is
uncomfortable and unhygienic and should only be used nowadays if other
apparatus is not available.

The edentulous mandible and an adequate complement of maxillary
teeth:
The splint or denture secured by circumferential wires to the low jaw is
joined to maxillary eyelet wires or arch bars by wires passed around the
hooks of the denture or splint or through the circumferential wires. Further
combinations of such problems will be met by the clinician, who will adapt
the basic techniques described to fit the particular circumstances.
FRACTURES OF THE TOOTH-BEARING SECTION OF THE
MANDIBLE :
The general principles of treatment of fractures of the mandible do not
differ essentially from the treatment of fractures elsewhere in the body. The
fragments are reduced into a good position and are then immobilized until
such time as bony union occurs. Traditionally immobilization of the mandible
has involved linking it temporarily to the opposing jaw by some form of
intermaxillary fixation (IMF). This has the considerable disadvantage to the
patient of preventing normal jaw function and restricting the diet to a liquid or
semi-solid consistency. Weight loss is common, oral hygiene is difficult to
maintain and convalescence is prolonged. Leonard (1987) has drawn attention
to a thesis by Bruksch at the University of Minnsota in which he
demonstrated a 30% reduction of ventilatory volume in patients subjected to
intermaxillary fixation.
For all these reasons, surgeons have looked for alternative methods of
treatment which avoided or shortened the period of intermaxillary fixation.
The most significant contemporary change in the treatment of mandibular
fractures, and in particular fractures of the dentate mandible, has been an

increasing trend towards rigid osteosynthesis by means of bone plates. In
skilled hands, consistently successful results are now being reported
(Cawood, 1985; Prein and Kellman, 1987; Raveh et al., 1987). However,
because of the sheer number of mandibular fractures and the limitation of
resources, such as operating theatre time, a considerable, proportion of these
fractures will continue to be treated by traditional methods and a general
overview is needed in a text such as this.
Reduction :
Reduction of a fracture means the restoration of a functional alignment
of the bone fragments. In certain situations this does not necessarily imply
exact anatomical alignment, e.g. fracture of the clavicle. However, in the
dentate mandible reduction must be anatomically precise when teeth are
involved which were previously in good occlusion. Less precise reduction
may be acceptable if part of the body of the mandible is edentulous or there
are no opposing teeth.
The presence of teeth provides an accurate guide in most cases by
which the related bony fragments can be aligned. The teeth are used to assist
the reduction, check alignment of the fragments and assist in the
immobilization. Whenever the occlusion is used as an index of accurate
reduction it is important to recognize any pre-existing occlusal abnormalities
such as an anterior or lateral open to previous contact areas. Teeth may on
occasions be brought into contact during reduction and yet be occluding
incorrectly owing to lingual inclination of the fractured segment.
Widely displaced, multiple or extensively comminuted fractures may
be impossible to reduce by means of manipulation of the teeth alone, in which
case open operative exploration becomes necessary.
In general, reduction and later immobilization is best effected under
general anaesthesia, but occasionally it is possible to employ local analgesia

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