Placement of impalnts

DIAGNOSIS AND TREATMENT
PLANNING
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DIAGNOSIS AND TREATMENT PLANNING
• To develop and implement a comprehensive and accurate plan for
the implant insertion, proper diagnostic procedure must be
observed and followed.

MEDICAL EVALUATION

DENTAL EVALUATION
• Bone at the preferred implant
site should be evaluated.
• The bone can be classified
into four types based on its
density.
 Dense compact bone
(D1 bone)
 Porous compact bone
(D2 bone)
 Coarse trabecular bone
(D3 bone)
 Fine trabecular bone
(D4 bone)

DENTAL EVALUATION
D1 BONE
• It consists of very dense compact bone
• It is found in anterior regions of the
mandible and in the lateral aspect of the
symphysis of the mandible
• Excellent stability to titanium implants
D2 BONE
• It has dense to porous compact bone on
the outside and coarse trabecular bone on
the inside.
• It is most commonly found in the anterior
portion of the mandible followed by the
posterior mandible.
• It provides excellent ridge healing.
• Threaded titanium implants are preferred
for such bone.

DENTAL EVALUATION
D3 BONE
• It has thinner porous compact bone and coarse
trabecular bone.
• It is found in anterior or posterior maxilla and
posterior regions of the mandible
• This type of bone is very easy to cut during
the surgical procedures
• Implants coated with Hydroxyapatite are
indicated to increase the bone contact.
• Gradual loading of implants is indicated.
D4 BONE
• Fine trabecular bone
• It has very less density and little or no cortical
bone.
• It is found in posterior maxilla in long-term
edentulous patient.
• It is the most difficult bone to obtain rigid
fixation.
• Access is difficult
• Limited area of contact with the implant.
Larger implant should be used to increase the
contact area. www.indiandentalacademy.com

DIAGNOSTIC
EVALUATION
• It involves the radiographic
evaluation of bone.
• The choice of radiologic
technique appropriate for a
given patient depends on
number of factors including:
 Implant to be used
 Position of the remaining
dentition
 Extent to which bone quality
or quantity is in question.www.indiandentalacademy.com

DIAGNOSTIC EVALUATION
PERIAPICAL
RADIOGRAPHS
• A periapical radiograph
provides a view of greater
accuracy with high resolution
to indicate cortical and
medullary bone density of a
limited region of the jaws.
BITE-WING
RADIOGRAPHS
• In these images, the superior
one third of the implant is the
region of interest. www.indiandentalacademy.com

OCCLUSAL RADIOGRAPHY
• Since maxillary and mandibular
occlusal radiographs give
somewhat distorted projection,
they are of no quantitative
utilization for implant dentistry.
PANORAMIC VIEW
• It is useful for identifying overall
view of maxilla and mandible.
• Normal anatomy and pathologic
conditions can be obtained of
dentoalveolar complex and
adjacent structures.

LATERAL CEPHALOMETRIC VIEW
• Lateral cephalometric view is useful to study skeletal jaw relationships.
• It gives an estimate of labiolingual dimensions.
• The lateral cephalometric radiographs one to one imaging of the buccal and lingual cortical
heights of the mandibular symphysis allows the dentist to determine precisely the
appropriate length and inclination of implants to be placed.
CT SCANNING ( COMPUTERIZED AXIAL TOMOGRAPHY SCANNING)
• A single, 3- dimensional accurate technique of bone measurement can be achieved with
CT scanning.
• Amount of available bone or lack of it can be established in millimeters.
• The exact location of mandibular canal can be plotted during surgery.
• The accurate information provided by CT scanning helps the implantologists to select the
proper implant type, size, numbers, location etc.
• With most advanced software technology, the radiologist can create 3-dimensional
reconstruction of maxilla and mandible very easily.
• Presently the software and hardware ( Dentascan) systems are available with which the
dentist can reformat the axial images directly in the office and superimpose appropriately
sized implants on them.

INTERACTIVE COMPUTER TOMOGRAPHY (ICT):-
• It enables the radiologist to transfer the imaging study to the clinician as a
computer file
• Enables the clinician to view and interact with the imaging study on his or
her own computer.

STUDY STONE CAST MODELS
• Study casts are made after all full arch impressions are taken for both the
arches.
• For accurate and successful treatment outcome, proper articulation of the
casts is mandatory on an articulator, reproducing patients natural occlusal,
relationship.
• Study cast models are very much useful in determining intraoral distances,
arch forms, and occlusal relationships.

TREATMENT PLANNING

SUITABILITY FOR IMPLANTS
• Prior to commencing any implant treatment.
FACTORS THAT NEED TO BE CONSIDERED INCLUDE THE :
1. Quality and quantity of bone present.
• Bone quality and the extent of ridge resorption are important factors to assess.
2. Age of the patients
– is an important consideration, as implants are problemtic if inserted in growing children
for the following reasons:
A. The use of implants in the anterior maxilla is contraindicated due to the possibility of the
mid-palatal suture is open.
B. Resorption in the posterior part of the maxilla, resulting from growth changes, could lead
to exposure of the implant into sinus.
C. The posterior aspect of the mandible continues to undergo growth changes in all 3 planes
of space and as such definitive implant placement in this area would be difficult to
estimate.
D. Even when growth is complete and the teeth appear fully erupted, infra-occlusion of
implant supported crowns may occur. This is a result of minimal continued eruption of
adjacent teeth, post adolescence and is most frequently seen with upper lateral incisors.

OPTIMAL POSITIONING OF
IMPLANTS
 ANGLE OF INSERTION
 PATH OF INSERTION
 RULE FOR CHOOSING PROPER SIZE OF IMPLANT
ACCORDING TO THE LENGTH OF THE IMPLANT
ACCORDING TO THE DIAMETER OF THE IMPLANT
 CLINICAL SITES FOR IMPLANT PLACEMENT
MAXILLARY SITES
MANDIBULAR SITES
 SURGICAL GUIDES

OPTIMAL POSITIONING HAS ALWAYS BEEN
CRITICAL TO THE EFFECTIVENESS OF
DENTAL IMPLANTS.
• The choice of location depends on the initial diagnosis, the purpose of the
implant therapy, the proximity of adjacent structures such as the
mandibular nerve and maxillary sinus, and esthetic factors.
• The optimum three dimensional position for each miniscrew is determined
from a panoramic or intraoral radiograph and a dental cast.
• To maximize the depth of cortical and cancellous bone while avoiding
adjacent roots, gingival papillae, neurovascular tissues and nasomaxillary
cavities, the clinician must consider three major parameters:
1. Topographical entry point of the implant
2. Anteroposterior angle of entry
3. Vertical inclination of entry

ANGLE OF INSERTION OF
MICROIMPALNT
• Recommended angles of the implant to
the long axes of the teeth are 10-20o
in
the mandible and from 30-40o
in the
maxilla.
• For a safe miniscrew insertion, the
insertion axis and the screw shape is
critical.
• If the screw is inserted perpendicular to
the dental axis, it might reach the
narrowest interradicular space earlier
than when inserted at an oblique angle
and should be embedded for no more
than 6-8mm of bone depth, i.e., 50% of
the buccolingual average measure
between first and second molars.
• A miniscrew insertion at 30-40o
to the
dental axis allows the insertion of a
longer screw in the available bone depth.
• Because of the reduced tip diameter, a
conic screw insertion has a lower risk of
damaging roots. www.indiandentalacademy.com

RULE FOR CHOOSING PROPER SIZE OF
IMPLANT
ACCORDING TO THE LENGTH OF MICROIMPLANT
• Usually, sizes more than 6mm in maxilla and 5mm in mandible of
microimplants are recommended.
• The cortical surfaces of the maxilla are thinner and less compact than those of
the mandible and accordingly will require longer microimplants.
• The proper length of microimplant is best selected during the pilot drilling.
• The path of insertion of microimplant can be in perpendicular direction to the
bony surface or in diagonal direction, to avoid injury to adjacent roots.
• Clinically in order to get better mechanical retention, it’s good to choose a
longer and thicker microimplant, rather than shorter and small one.
• Review the soft tissue thickness as well as the quality of bone at the sites for
microimplant placement.

RULE FOR CHOOSING PROPER SIZE OF
IMPLANT
ACCORDING TO THE DIAMETER OF MICROIMPLANT
• 1.2mm diameter and 1.3mm in diameter can all withstand up to 450g of
orthodontic force when patient has good quality of cortical bone.
• Using forces greater than 300g, clinicians should select 1.4mm in diameter.
• In the mandible the buccal surfaces and retro-molar areas offer adequate
thickness and high quality cortex for the acceptance of microimplants.
• Usually, 4-5mm in length with 1.2- 1.3mm in diameter provide adequate
retention.
• Micro-implant with 1.4-1.6mm in diameter might improve retention when
cortical bone is less dense or greater fore is needed. E.g., when moving the
entire mandibular dentition distally.

CLINICAL SITES FOR MICROIMPLANT
PLACEMENT

MAXILLARY ZONE

MANDIBULAR ZONE

STENTS

STENTS FOR ACCURATE MINISCREW INSERTION
• Improper positioning may result in interference with the required tooth movement and
hence limit the effectiveness of the skeletal anchorage.
• Visual and instrument access can be difficult when miniscrew are placed in posterior
or palatal locations.
• Several manufacturers and authors currently recommend the use of a brass separating
wire or custom-made wire guide, which is radiographed in place to show the
relationship to the planned insertion site and the adjacent dental roots.
• Aside from the additional radiographic exposure, such wire markers provide only
limited topographical information, rather than a direct indication of the implant
angulation.

The ideal solution would be a stent that would transfer the
planned three-dimensional implant position to the
surgical placement procedure.
STENT:
• A surgical or a guiding stent is a prosthetic appliance,
which helps to orient and position the implants.
• The term stent was coined after an English dentist
Charles R. Stent.

SURGICAL GUIDE

THREE DIMENSIONAL SURGICAL GUIDE

ADVANTAGES OF STENT
1. The design and fabrication are simple.
2. Provides reliable guidance for either the pilot drill or the self drilling
miniscrew in terms of both location and angulation.
3. It allows access for both visual monitoring and saline irrigation.
4. Provides accurate three dimensional positioning of miniscrews so that bone
support can be maximized and damage to adjacent structures can be avoided.
5. It reduces the need for direct visual access to posterior or palatal insertion
sites.
6. It is particularly valuable when the operator is inexperienced or the insertion
is not performed by the prescribing orthodontist.
7. By minimizing lateral movement of the pilot drill and implant, it also
prevents widening of the implant hole and thus improve mechanical stability.
8. It is the safest means of ensuring accurate implant placement.
9. The patients degree of comfort with the procedure is improved when the
position and direction of the bur are not being constantly revised during
surgery. www.indiandentalacademy.com

SURGICAL PROCEDURE FOR
IMPLANT PLACEMENT
METHODS OF MICROIMPLANT
INSERTION
MICROIMPLANT DRIVING METHODS
SURGICAL PROCEDURE FOR IMPLANT
PLACEMENT
MICROIMPLANT
MINI IMPLANT

MICRO-IMPLANT DRIVING METHODS
1. PRE-TAPPING
2. SELF-DRILLING
3. SELF-TAPPING

Micro-Implant Driving Methods
1.Pre-tapping procedure
1.Drilling
2.Tapping
3.Driving
for some Prosthodontic Implantswww.indiandentalacademy.com

2. Self–drilling procedure
1) Driving
or
After indentation Without indentation
(suitable for Diagonal insertion
& thick cortical bone)
(suitable for Perpendicular insertion
& thin cortical bone)
Dia.; less than 1.5mm Dia.; more than 1.5mm
for Ortho. Micro- &Mini-Implant
One-stepTwo-step

3. Self –tapping procedure
3) Drivingfor Ortho.Micro-Implant:
Dia.; less than 1.3mm
1) Indentation
2) Drilling
or
One step
Two step
(in case of very thick cortical bone)
or

MINI IMPLANT PLACEMENT

MINI IMPLANT

SURGICAL PLACEMENT OF IMPLANT
IMPLANT MAINTENANCE
1. After surgery the surrounding soft tissues must be maintained to ensure
longevity of the implant.
2. Plaque accumulation near the gingival margin can cause perimucositis.
3. Prolonged inflammation leads to breakdown of bone around implants and
periimplantitis, this without proper management, can lead to implant
failure.
HYGIENE PROTOCOL
1. Proper home care is needed to prevent plaque accumulation around the
implant. The use of interdental brushes or rotary unitufted brush is
recommended for better access.
2. Antimicrobial agents like chlorhexidine gluconate (0.12%) should be used
to control pathogenic bacteria.
3. Regular recall visits should be done every three months.
4. Periapical radiographs should be taken every 6 months.

BONE HEALING AFTER IMPLANT
PLACEMENT

LOADING OF IMPLANT

LOADING OF IMPLANT
• Maximal loading of the
implant depends upon:
 Design of the fixures
 Biomechanical
reqiurements.
 Anatomic requirements
 Degree of
osseointegration
• Immediate loading should
be limited to about 50CN
of force, otherwise
excessive loading leads to
screw loosening and
failure of the implants. www.indiandentalacademy.com

FAILURE IN MINI IMPLANTS

FAILURES IN MINI IMPLANTS
SCREW-RELATED PROBLEMS:
1. A screw can fracture if it is too narrow or the neck area is not strong enough to withstand the
stress of removal. The solution is to choose a conical screw with a solid neck and a diameter
appropriate to the quality of bone.
2. Infection can develop around the screw if the transmucosal portion is not entirely smooth. If a
screw system with variable neck lengths is used, the clinician can select one that suits the
particular implant site.
OPERATOR – RELATED PROBLEMS:
1. Application of excessive pressure during insertion of a self-drilling screw can fracture the
screw.
2. Overlengthening a screw can cause it to loosen. It is crucial to stop turning the screw as soon as
the smooth part of the neck has reached the periosteum.
3. With a bracket-like screw head, the ligature should be placed on top of the screw in the slot
perpendicular to the wire. Turning the ligature around the screw will make it impossible for the
patient to keep the area free of inflammation.
4. It is important not to wiggle the screwdriver when removing it from the screw head. The screw
driver will not stick if the long extension is removed before the part surrounding the screw.

FAILURES IN MINI IMPLANTS
PATIENT-RELATED PROBLEMS:
1. The prognosis for primary stability of a mini-implant is poor in cases
where the cortex is thinner than .5mm and the density of the trabecular
bone is low.
2. In patients with thick mucosa, the distance between the point of force
application and the center of resistance of the screw will be greater than
usual, thus generating a large moment when a force is applied.
3. Loosening can occur, even after primary stability has been achieved, if a
screw is inserted in an area with considerable bone remodeling because
of either the resorption of a deciduous tooth or post- extraction healing.
4. Mini-implants are contraindicated in patients with systemic alterations in
the bone metabolism due to disease, or heavy smoking.

Placement of impalnts

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