Interpreting Radiographs

What to Look For Dental caries Periapical pathology Calcified pulps Changes in alveolar bone pattern Alveolar bone height

What to Look For (Cont'd) Etiologic agents that promote dental disease Overhanging margins on restorations Calculus Open contacts

Root caries may be confused with cervical burnout (see below). Cross-section (red line at right)

Cervical burnout Radiolucency seen above left (arrow) disappears on periapical film of same tooth (above right).

Anterior Cervical Burnout bone level cervical burnout area

Cervical burnout in the anterior region due to gap between enamel (red arrows) and alveolar bone over root (blue arrows).

Normal Alveolar Bone Height 1.5 to 2 mm below CEJ of adjacent teeth Bone forming alveolar crest should be smooth and intact Slight radiolucent space adjacent to the root surface Visible distinct crestal lamina dura

CEJ 1-1.5 mm

Normal Alveolar Bone Height

Alveolar crests more pointed anteriorly

Corticated alveolar crests

Periodontal Disease Vertical Bitewings or paralleling PA’s best for diagnosis. Higher kVp recommended (long scale, low contrast). Compare images from different visits (using same technique).

Limitation of Radiographs Two-dimensional film with overlapping bony walls, superimposed roots Clinical picture more advanced Relationship of hard to soft tissues not evident

Periodontitis Involvement: Localized Generalized

Horizontal bone loss: Parallel to line drawn between adjacent CEJ’s Vertical (Angular) bone loss: More bone destruction on interproximal aspect of one tooth than on the adjacent tooth

Contributing Factors Occlusal trauma Open contacts Overhangs, poor contours Calculus Post-extraction defects Systemic involvement (diabetes, blood disorders, hormonal changes, stress, AIDS)

Gingivitis No bone loss No radiographic signs

Recognizing Early Alveolar Bone Loss Increasing area of radiolucency where the alveolar crest and PDL meet Widening periodontal ligament space Loss of integrity of crestal lamina dura

Early moderate adult periodontitis

Moderate adult periodontitis (red arrows point to calculus)

Moderate adult periodontitis

Severe adult periodontitis

Severe adult periodontitis

Severe adult periodontitis

Restorative Materials Radiopaque: Structures with higher object density, such as amalgam, gold, silver points, pins, gutta percha, porcelain. Radiolucent: Structures with lower object density, such as older composites and bonding agents.

Gold crowns, amalgams

Retention pins

porcelain crowns

crown crown amalgam cast post gutta percha silver points

Red arrows point to bases Green arrow indicates recurrent caries with fractured restoration

old new Composites

Proceedure for radiographic critiques And interpretations.

Assessing Radiographs Determine if the radiographs are diagnostically acceptable Look for technique errors Look for processing errors Recognize normal structures Systematically assess teeth and supporting structures Place radiographs in patient chart