Abstract
The purpose of this study is to establish a reliable method to evaluate the change of alveolar bone and to correlate the roentgenographic estimation with various clinical indices.
Using a collimating device reported by Kawasaki which consisted of a individual film holder and a pointer, intraoral roentgenographs were taken and microdensitometric measurements were undertaken on the proximal alveolar crest area on the films. A cupper stepwedge placed at the outer margin of the film was used as the densitometric scale.
The spot diameter of 0.6mm was chosen as the size for the microdensitometric sweep. The key point to obtain topographic relationship among films was found in the superposition according to the shadow of the traveculae at the cervical area on the films. In the case of anterior teeth, the avoidance of lip and cheek between the stepwedge and the focus enhanced the accuracy of the gray scale but this was not possible in posterior teeth.
Fifteen patients with the diagnosis of chronic marginal periodontitis were selected and the effect of plaque control and scaling on the alveolar radiopacity, probing pocket depth (PD), gingival index (GI), bleeding index (BI), plaque index (Pl. I) and calculus Index (CI) were examined. The initial diagnostic procedures were carried out on the first visit of the patient. The follow-up examinations were made at 3 months and 6 months after the end of initial preparation.
The average increase of alveolar crest height was 0.2mm and the average increase of radiopacity at alveolar crest area was 1.3×10-2mmCu equivalent at 6 months after the end of initial preparation. When the patients were divided into two groups, i. e. the group who had equal to or more and the group who had less than the average opacity at the alveolar crest area, more increase in radiopacity was observed in the latter group. The group of patints who had smaller Pl. I value than the average showed better clinical improvement, but it was not possible to prove statistical significancy in the change of radiopacity.
The procedure described here is a reliable method to evaluate the state of proximal alveolar crest area in periodontal patients.
