Radiographic alveolar bone morphology and progressive periodontitis.

Background: This study evaluated the relationship between radiographic crestal alveolar bone morphology and progressive periodontitis.

Methods: A total of 1,356 posterior interproximal sites in 56 adults treated for chronic periodontitis and receiving systematic 3-month maintenance care were scored for angular or horizontal marginal bone morphology, as well as for alveolar crestal lamina dura, on radiographs obtained at baseline of a 30-month post-treatment period. Semi-annually, the study patients were clinically evaluated for progressive periodontitis. Logistic regression analysis assessed baseline parameters to progressive periodontitis over the 30-month post-treatment period.

Results: Progressive periodontitis was detected at 33 (2.4%) posterior interproximal sites in 20 (35.7%) patients. Sites with post-treatment angular bony defects developed progressive periodontitis more frequently (14.7%) than sites with a horizontal bone topography (1.8%). Angular bony defects (odds ratio = 10.6) and periodontal probing depths ≥5 mm (odds ratio = 4.2) were identified as statistically significant independent predictors of progressive periodontitis at posterior interproximal sites. Angular bony and horizontal lesions with intact radiographic lamina dura revealed an absence of progressive periodontitis through 24 months.

Conclusions: Post-treatment presence of angular bone morphology and periodontal probing depths ≥5 mm significantly increased risk of progressive periodontitis at posterior interproximal sites. Sites of all morphology and probing depth that displayed radiographic crestal lamina dura at post-treatment baseline exhibited clinical stability for ≥24 months.