**6.1 Periodontitis**

*Periodontal Disease - Diagnostic and Adjunctive Non-surgical Considerations*

interproximal spaces of the area of interest [20] (**Figure 2**).

**4. Bone destruction in periodontal disease**

**4.1 Bone loss**

*4.1.1 Amount*

*4.1.2 Distribution*

different surfaces of the same tooth [23].

**5. Pattern of bone destruction**

through the contact areas of the teeth and perpendicular to the film. Thus the projection geometry of the bite-wing films allows the evaluation of the relationship between the interproximal alveolar crest and the CEJ without distortion. If the periodontal bone loss is severe and the bone level cannot be visualized on regular bite-wing radiographs, films can be placed vertically to cover a larger area of the jaws. More than two vertical bite-wing films might be necessary to cover all the

Early destructive changes of bone that do not remove sufficient mineralized tissue cannot be captured on radiographs. Therefore slight radiographic changes of the periodontal tissues suggest that the disease has progressed beyond its earliest stages.

The radiographic image tends to underestimate the severity of bone loss. The difference between the alveolar crest height and the radiographic appearance ranges

Radiographs are an indirect method for determining the amount of bone loss in periodontal disease; they image the amount of remaining bone rather than the amount lost. The amount of bone lost is estimated to be the difference between the physiologic bone level and the height of the remaining bone. The distance from the CEJ to the alveolar crest has been analyzed by several investigators. Most studies, conducted in adolescents, suggest a distance of 2 mm to reflect normal

The distribution of bone loss is an important diagnostic sign. It points to the location of destructive local factors in different areas of the mouth and in relation to

In periodontal disease the interdental bone undergoes changes that affect the lamina dura, crestal radiodensity, size and shape of the medullary spaces, and height and contour of the bone. Height of interdental bone may be reduced, with the crest perpendicular to the long axis of the adjacent teeth horizontal bone loss; or angular or arcuate defects angular, or vertical, bone loss; could form [24–26]. Radiographs do not indicate the internal morphology or depth of craterlike defects. Also, radiographs do not reveal the extent of involvement on the facial and lingual surfaces. Bone destruction of facial and lingual surfaces is masked by the dense root structure, and bone destruction on the mesial and distal root surfaces may be partially hidden by superimposed anatomy, such as a dense mylohyoid ridge. In most cases, it can be assumed that bone losses seen interdentally continue

in either the facial or the lingual aspect, creating a troughlike lesion [27].

The earliest signs of periodontal disease must be detected clinically [16].

from 0 to 1.6 mm, mostly accounted for by X-ray angulation [21].

periodontium; this distance may be greater in older patients [22].

**52**

Radiographic changes in periodontitis follow the pathophysiology of periodontal tissue destruction and include the following [29]:

1.Fuzziness and disruption of lamina dura crestal cortication continuity is the earliest radiographic change in periodontitis and results from bone resorption activated by extension of gingival inflammation into the periodontal bone. Depicting these early changes depends greatly on the radiographic technique, as well as on morphological changes. No correlation was found between

#### **Figure 3.**

*Radiographic changes in periodontitis. (A) Normal appearance of interdental bone. (B) Fuzziness and a break in the continuity of the lamina dura at the crest of the bone distal to the central incisor (*left*). There are wedgeshaped radiolucent areas at the crest of the other interdental bone. (C) Radiolucent projections from the crest into the interdental bone indicate extension of destructive processes. (D) Severe bone loss.*

lamina dura in radiographs and the presence or absence of clinical inflammation, bleeding on probing, periodontal pockets, or clinical attachment loss. Therefore it can be concluded that the presence of an intact crestal lamina dura may be an indicator of periodontal health (**Figure 3**).

