1. Essentials of dental Radiography & Radiology-
Eric Whaites.
2. Oral Radiology, Principles and Interpretation. 7th
Edition. Stuart C. White, and Michael J. Pharoah

Radiographic interpretation for caries
• C1- Incipient: enamel caries less than ½
way through enamel.
• C2- Moderate: enamel caries penetrating
at least ½ way through enamel, but not
involving DEJ
• C3- Advanced: caries of enamel and
dentine, extending DEJ and ½ way into
dentine.
• C4- Severe: caries of enamel and dentine
extending more than ½ way dentine
towards pulp cavity.
Classification of radiographic caries:

root surface carious lesions
carious lesion in the distal root surface of the maxillary second
molar (short arrow) and an example of cervical burnout (long
arrow). Note the sharp line from overlapping roots that delineates
the radiolucent cervical burnout.
A carious lesion developing at the margin
of an existing restoration may be termed
secondary or recurrent caries.

Radiographic interpretation of periapical disease.
• Acute apical periodontitis: Small periapical radiolucency, slight widening
of PDL space, intact lamina dura.
History, symptoms and clinical tests differentiates.
• Acute apical abscess:
• Phoenix abscess (Chronic apical periodontitis upon suddenly becomes
symptomatic): frank periapical radiolucency, break in lamina dura.
• Periapical granuloma: periapical radiolucency , discontinuity in lamina dura
• Periapical cyst:
• Apical condensing osteitis: well circumscribed radiopaque mass of sclerotic
bone surrounding the radiolucent area of effected roots.

Radiographs are especially helpful in the evaluation of the
following features:
• Amount of bone present
• Condition of the alveolar crests
• Bone loss in the furcation areas
• Width of the periodontal ligament space
• Local irritating factors that increase the risk of periodontal disease
➢ Calculus
➢ Poorly contoured or overextended restorations
• Root length and morphology and the crown-to-root ratio
• Open interproximal contacts, which may be sites for food impaction
• Anatomic considerations
➢ Position of the maxillary sinus in relation to a periodontal deformity
➢ Missing, supernumerary, impacted, and tipped teeth
• Pathologic considerations
➢ Caries
➢ Periapical lesions
➢ Root resorption
Radiographic interpretation of periodontal diseases.

General Radiographic Features
of Periodontal Disease
• These changes can be divided into changes in the morphology of the supporting
alveolar bone and changes to the internal density and trabecular pattern.
• Early Bone Changes
• The early lesions of chronic periodontitis appear as areas of localized
erosion of the interproximal alveolar bone crest.
• The anterior regions show blunting of the alveolar crests and slight loss of
alveolar bone height.
• The posterior regions may also show a loss of the normally sharp angle
between the lamina dura and alveolar crest.
Initial periodontal disease is seen as a loss
of cortical density and a rounding of the
junction between the alveolar crest and
the lamina dura

Horizontal bone loss is a term used to describe the
radiographic appearance of loss in height of the
alveolar bone around multiple teeth; the crest is still
horizontal) but is positioned apically more than a few
millimeters from the line of the cemental enamel
junctions (CEJs).
Horizontal bone loss may be mild, moderate, or
severe, depending on its extent.
▪ Mild bone loss may be defined as
approximately a 1- to 2-mm loss of the
supporting bone.
▪ Moderate loss is anything greater than 2 mm
up to loss of half the supporting bone height.
▪ Severe loss is anything beyond this point.
Vertical (or angular) osseous defect describes the
types of bony lesion where the crest of the remaining
alveolar bone typically displays an oblique angulation
to the line of the CEJs in the area of involved teeth.
Horizontal bone loss
Vertical bone defect

Interdental Craters
• The interproximal crater is a two-walled, troughlike depression that forms
in the crest of the interdental bone between adjacent teeth.
Radiographically this presents as a bandlike or irregular region of bone
with less density at the crest, immediately adjacent to the more dense
normal bone apical to the base of the crater.
Buccal or Lingual Cortical Plate Loss
• The buccal or lingual cortical plate adjacent to the teeth may resorb. Loss
of a cortical plate may occur alone or with another type of bone loss such
as horizontal bone loss. This type of loss is indicated by an increase in
the radiolucency of the root of the tooth near the alveolar crest.
.
Interdental Craters
Buccal or Lingual Cortical Plate Loss

Osseous Deformities in the Furcations of Multirooted Teeth
• Progressive periodontal disease and its associated bone loss may extend
into the furcations of multirooted teeth. Radiographically, a profound
radiolucent lesion within the furcation region (arrow) resulting from loss of
bone in the furcation region and the buccal and lingual cortical plates.
Calculus
• Calculus may be seen as small angular radiopaque deposits projecting
between interproximal surfaces of the teeth
Osseous Deformities in the Furcations Calculus

Limitations of radiographs:
a. Radiographs provide a two-dimensional view of a three-dimensional situation.
b. Radiographs typically show less severe bone(40%)/mineral(30%) destruction
than is actually present. The earliest (incipient) mildly destructive lesions in
bone do not cause a sufficient change in density to be detectable.
c. Radiographs do not demonstrate the soft-tissue to hard- tissue relationships
and thus provide no information about the depth of soft tissue pockets.
d. Bone level is often measured from the cemento-enamel junction; however,
this reference point is not valid in situations in which either overeruption or
severe attrition with passive eruption exists.
Upon these reasons, although radiographs play an invaluable role in
treatment planning, their use must be supplemented by careful clinical
examination.

End