[The episodic progression of untreated adult periodontitis]

Marginal periodontitis in humans and animals is characterized by site-specific episodes of accelerated clinical attachment loss, which are interspersed between periods of quiescence of variable length. Diagnosis of episodic periodontitis progression could allow for early interception and arrest of progression. Currently available diagnostic techniques are not sensitive enough to detect phases of periodontitis progression. Diagnostic tests should be developed which are sensitive and practical enough to determine need and success of periodontal treatment at specific sites or sections of a dentition. In a longitudinal study on untreated periodontitis in humans, progressing and nonprogressing periodontal lesions were identified and investigated using clinical, microbiological, histological and immunohistochemical methods. Ten adult patients with untreated advanced periodontitis were monitored monthly for ten months. Attachment levels and probing depth were determined at six sites of every tooth. Corresponding contralateral sites were identified where one site had lost 2 mm or more probing attachment since the previous session (P-site), and the other site had not (C-site). The results showed that bleeding on probing was positively and statistically significantly correlated with episodic clinical attachment loss. The error in probing attachment level measurements varied with the tooth type and was greatest at molars. Over time the measurement error became smaller. In deeper pockets the probing error was greater than in shallow pockets. It appears that in order to accept clinical progression of periodontitis an increase in probing attachment loss or probing depth of more than 2 mm has to be observed. Using the mean attachment loss per site in a dentition at six or nine months after initial measurements should enable the dentist to discriminate patients with a higher rate of periodontitis progression from patients with a low rate. Darkfield microscopy used for assessment of subgingival bacterial populations seems to be without diagnostic value for differentiation between P- and C-sites.