Alveolar bone loss and crowding in adult periodontal patients

The present study aimed to examine whether local crowding and tooth angulation in the mandibular incisor region led to alveolar bone loss in patients with moderate periodontal disease. The sample comprised 27 patients from the Department of Periodontology aged 29-57 yr. Mesiodistal tooth angulation and crowding, defined as an overlap of 2 mm or more, were assessed from dental casts. Alveolar bone loss was assessed from intraoral standardized paralleling radiographs by two methods, the absolute bone level (ABL), recorded from the cementoenamel junction, and the relative bone level (RBL), a new measure, expressing the bone level relative to the two adjacent interradicular crests. Contralateral sites were used as controls. A significant difference in bone level was found between crowded and non-crowded sites by both methods (-1.7 mm, P less than 0.001). This indicates that in periodontal patients local crowding and tooth angulation predisposes to increased bone loss. Analysis of the correlations between tooth angulations and the two measures of bone loss indicated that the RBL value is a more sensitive measure of localized bone loss.