Assessment of alveolar bone levels from intraoral radiographs in subjects between ages 15 and 94 years seeking dental care.

Studies have shown that <20% of the US population has periodontal disease. Studies of radiographs have shown that alveolar bone loss increases with age. Bone loss assessed from intraoral radiographs describing 10,282 teeth from 416 subjects seeking dental care during a 3 month period at the University of Washington were studied. The mean age of the subjects was 47.2 years (SD+/-15.2). The youngest subjects (15-24) had on average 29.6 teeth (SD+/-2.2) and the oldest subjects (75-94) 19.3 teeth (SD+/-6.6). This difference was statistically significant (F=16.57, p<0.001). No association was found between alveolar bone loss (CEJ-ABC), and TMD symptoms. Smoking was significantly associated with both general bone loss (CEJ-ABC) (chi(2)=114.9, p<0.0001), and vertical bone defects (angular) (chi(2)=101.8, p<0.0001). In this study population (15-94 years), alveolar bone loss progressed as defined by the slope (beta=0.29) between age 15-44, but was almost flat from age 50 years (beta=0.04). The data suggested an overall rate of alveolar bone loss of 0.02 mm per year. Stepwise multiple regression analysis showed that smoking was the primary factor in bone loss (t= 7.7, p<0.0001), followed by age (t=7.0, p<0.001) and gender (t=3.0, p<0.01). TMD symptoms could not explain the presence and severity of horizontal or vertical defects. If the CEJ-ABC distance above the mean plus 2x the SD was used as the cutoff value to define abnormal bone levels, 10.9% of the younger (15-45 years), and 10.7% of the older subjects (50-94) had significant alveolar bone loss. 73.9% of the younger and 100% of the older subjects with such extent of alveolar bone loss were smokers.