Radiographic

Interpretation

Dental Radiography

• Questions• How does the radiographic

examination contribute to the detection of caries?

• What factors may influence caries interpretation?

• What is the radiographic appearance of: incipient, moderate, advanced and severe caries?

Detection of Caries

• Clinical examination and radiographs are necessary to detect dental caries• Radiographs enable the dental

professional to identify carious lesions that are not visible clinically

• It also allows the dental professional to evaluate the extent and severity of carious lesions

Clinical Examination

• Some carious lesions can be detected simply by looking in the mouth, and others cannot• The mirror can be used to reflect light,

allow for indirect vision, and retract the tongue

• The explorer can be used to detect changes in consistency in pits, grooves, and fissures of teeth

Clinical Examination

• Color changes may be observed• Occlusal surfaces may show dark

staining in fissures, pits, and grooves• Smooth surfaces may exhibit a chalky

white spot or opacity• An interproximal ridge may appear

discolored

Radiographic Examination

• A carious area appears radiolucent because decreased density allows for greater penetration in the carious area• The bite-wing radiograph provides the

dental professional with the greatest amount of diagnostic information

• A periapical radiograph taken with paralleling technique may also be used

Factors Influencing Caries Interpretation• Radiographs must be of diagnostic

quality• Examples may include

• Improper horizontal angulation on a bitewing film

• Errors in exposure with improper contrast and density

Interproximal Caries• Interproximal

• Between two adjacent surfaces• Typically seen on dental radiographs at

or just below the contact point• As caries progresses through the

enamel, it typically assumes a triangular configuration

• When it reaches the DEJ, it spreads laterally and progresses through dentin

• Classified as incipient, moderate, advanced, and severe

Incipient Interproximal Caries

• Extends less than halfway through the thickness of enamel• An incipient or Class I lesion is seen

only in enamel

Moderate Interproximal Caries

• Extends more than halfway through enamel but does not involve the DEJ• A moderate or Class II lesion is seen

only in enamel

Advanced Interproximal Caries

• Extends to or through the DEJ and into dentin, but does not extend into dentin more than half the distance toward the pulp• An advanced or Class III lesion affects

both enamel or dentin

Severe Interproximal Caries

• Extends through enamel and dentin more than half the distance toward the pulp• A severe or Class IV lesion involves

both enamel and dentin and may appear clinically as a cavitation in the tooth

Occlusal Caries

• Caries that involve the chewing surface of posterior teeth• “A thorough clinical exam is the

method of choice for the detection of occlusal caries”

• Early occlusal caries is difficult to see on a dental radiograph

Incipient Occlusal Caries

• Cannot be seen on a dental radiograph

• Must be detected with an explorer or DiagnoDent

Buccal and Lingual Caries

• These are difficult to detect on radiograph because they are superimposed on tooth structure• If seen on film, they appear as a

circular radiolucent area

Root Surface Caries

• Ivolves only the roots of teeth• On radiograph, it appears as a

cupped-out or crater-shaped radiolucency below the CEJ

• Early lesions may be difficult to detect on radiograph

Recurrent Caries

• Occurs adjacent to an existing restoration• It appears as a radiolucent area just

beneath a restoration• It is most often located beneath the

interproximal margins of a restoration

Rampant Caries

• Advanced and severe caries affecting a number of teeth• Associated with children with poor

diets and adults with decreased salivary flow