Radiographs play an important role in the diagnosis and treatment of periodontal diseases. They provide important information regarding the anatomical structures and periodontal bone loss.
3. “Xrays were discovered in 1895 by
professor William Conrad
Roentgen and Dr.Otto Walkhoff
is credited with the first dental
radiograph
3
4. INTRODUCTION
4
◦ Radiographs are a VALUABLE
TOOL for the diagnosis of
periodontal disease, estimation of
severity, determination of
prognosis and evaluation of
treatment outcome
◦ Radiographs are an ADJUNCT to
the clinical examination not a
substitute for it
5. RADIOGRAPHIC
TECHNIQUES
5
◦ Radiographs can be divided
into extraoral and intraoral
radiographs
◦ Intraoral – bitewing, periapical
and occlusal
◦ Intraoral periapical –
commonly done for a part of
the dentition whereas bite wing
radiographs are done for
posterior teeth
6. 6
◦ Occlusal radiographs – usually
done to find out buccolingual
or buccopalatal positions of the
impacted canines or third
molars to determine the extent
of diseases like cysts
◦ Extraoral – orthopantomogram
(OPG) – most commonly used
– complete bilateral view of
maxilla, mandible and TMJ
8. 8
Prichard established following FOUR CRITERIA to determine
adequate angulation of periapical radiographs:
1.The radiograph should show tips of molar cusps with little
or none of the occlusal surface showing
2.Enamel caps and pulp chambers should be distinct
3.Interproximal spaces should be open
4.Proximal contacts should not overlap unless teeth are out
of line automatically
9. Positioning guidelines for intraoral
radiographs
Paralleling technique:
Most accurate
Xray film is kept parallel to the teeth
Xray beam is directed at right angles
to the teeth and Xray film
Disadv – shallow palate – keeping
film parallel becomes difficult
10. Positioning guidelines for intraoral
radiographs
Bisecting angle technique:
Receptor is placed diagonally to the
teeth
Xray beam is directed at right angles
to the plane that is midway between
Xray film and teeth
Useful technique when receptor
placement cannot be achieved due to
shallow palate, pre of tori
11. STANDARDISED
RADIOGRAPHIC
TECHNIQUES
11
◦ Standardised reproducible
techniques – for pre-treatment and
post-treatment comparisons –
using position indicating device
◦ Standardisation of exposure and
development time, type of film,
Xray angulation minimises
image distortion
◦ Grid calibrated in millimeters over
the radiograph – calculate bone
levels
12. Radiographic findings of healthy
periodontal structures
Tooth is surrounded by a thin
radiolucent space which houses the pdl
Width of pdl – tooth under occlusal
overload – width is increased
Alveolar bone surrounding the tooth
root – radiopaque line just adjacent to
pdl space – lamina dura
13. 13
Radiographically it appears as a white line but in reality
it is perforated by numerous small foramina, traversed by
blood vessels, lymphatics and nerves which pass between pdl
and bone – continuity and integrity examined carefully on
radiograph
14. 14
The level of the crest of the interdental bone is parallel to the line
joining the CEJ of the adjacent teeth
Interdental bone – thin between anterior teeth due to less
interdental space and wide between posterior teeth – wide interdental
space
Bone resorption of interdental bone due to periodontal disease –
crest of the interdental bone – angulated
Most common reason for radiolucency in the apical region of the
root – endodontic involvement
15. 😉
15
Bone loss in Periodontal Disease
Minor bone loss on the buccal aspect is overlapped by
intact lingual bone, thus bone loss on one aspect may be
camouflaged by bone on the opposite side
Thus, early signs of periodontitis like deepening of
periodontal pocket or recession are best visualised
clinically
Actual severity of periodontal destruction is more than
as shown on radiograph
16. 16
The amount of bone lost is calculated
arbitarily by estimating the difference
between the physiological bone level and the
height of bone remaining
Distance between CEJ and the alveolar
crest in a healthy periodontium is 2mm
17. 17
How to assess for bone loss on radiograph????
The interproximal bone loss may be parallel to the line joining
the CEJ – Horizontal bone loss
At an angle to the line joining the CEJ of adjacent teeth –
Angular or Vertical bone loss
Topography of the bone defect cannot be accurately assessed
by the radiograph – bone destruction that occurs in the
cancellous bone is obscured by the
dense buccal and lingual/palatal
Cortical plates
18. 18
A minimum of 0.5-1mm reduction in the
level of cortical plate is required to permit the
radiographic visualisation of bone loss of
cancellous bone
The best method to check for the defect
morphology is surgical exposure of the area
19. 19
Radiographic features of bone loss in
periodontitis
Imp radiographic feature of periodontitis: fuzziness
and discontinuity of the lamina dura
Radiographic findings should not be correlated to
the clinical findings – intact lamina dura
indicates periodontal health ; discontinuity or
fuzziness of lamina dura does not indicate pre of
inflammation, BOP, periodontal pockets or loss of
attachment
20. 20
Bone resorption on lateral aspect of interdental septum
– wedge shaped radiolucent area on the mesial or
distal aspect – widening of pdl
Radiographic appearance of finger like radiolucent
projections that extend from the crest of the bone into
the septum
Localised aggressive periodontitis – vertical arc like
destructive pattern
Generalised aggressive periodontitis – severe bone loss
21. 21
Arc shaped bone lossWedge shaped
radiolucent area
Finger like radiolucent
projections
23. 23
RADIOGRAPHIC
FINDINGS OF
PERIODONTAL
ABSCESS
Acute changes cannot be visualised on
the radiograph due to minimal changes
in the alveolar bone whereas chronic
lesion can be visualised
Periodontal abscess – localised to the
soft tissue wall – less likely to produce
radiographic changes
Periodontal abscess present on lingual
and facial surfaces of teeth are obscured
by the root surface on radiograph – less
visible. Thus radiograph is not a good
indicator of periodontal abscess
25. 25
Osteosclerosis
Homogenous
radiodense areas
– mandible more
affected –
deposition of
excessive bone
during repair
Fibrous dysplasia
Finely trabeculated
radiodensity –
ground glass
appearance
Paget’s disease
Radiolucent – osteolysis dominates, middle stage: -
deposition of bone – cotton wool appearance and late
stage – osteoblastic apposition
Vestibulum nec
congue tempus
SPECIFIC
DISEASES
27. 27
CONCLUSION
Radiographs – Important role in the diagnosis of periodontal
diseases
Important information regarding anatomical structures
and periodontal bone loss