Risk indicators for future clinical attachment loss in adult periodontitis. Tooth and site variables.

In an earlier report, we examined the relationship of patient-derived clinical and epidemiological variables to the risk for future clinical attachment loss (CAL) in chronic adult periodontitis. We determined that the extent of the patient's existing periodontal disease as measured by mean attachment loss (MAL) and the patient's age were the most important patient-derived risk indicators for CAL among those factors evaluated. In this study, we examined the tooth and site variables that were associated with CAL. Seventy-five patients with chronic adult periodontitis were followed for 6 months. Clinical data at baseline, including attachment level and probing depth, were obtained from six sites per tooth. The hazard rate for CAL at all sites was 2.0%, and 4.1% of teeth displayed at least one site with CAL. Mandibular and maxillary molars and maxillary premolars displayed the highest incidence of CAL (6.1%, 5.6%, 5.5%, respectively), while maxillary anterior teeth (1.8%) and mandibular premolar teeth (2.1%) demonstrated the lowest incidence. The greatest number of sites demonstrating CAL had an existing attachment level of 4 to 7 mm and a probing depth of less than or equal to 5 mm. When the data were converted to hazard rates, however, an increase in hazard rate was seen with increasing existing attachment loss or probing depth. When MAL was considered, patients with mild and moderate periodontitis demonstrated a relatively low incidence of CAL at sites with less than or equal to 7 mm of existing attachment loss. Patients with severe periodontitis exhibited greater hazard rates for sites with 0 to 3, 4 to 5 and 6 to 7 mm of existing attachment loss.(ABSTRACT TRUNCATED AT 250 WORDS)