Alternation of Alveolar Bone Mineral Distribution in Periodontitis Patients

Objectives: Periodontitis is characterized by loss of alveolar bone (AB) surrounding teeth. As such, active bone remodeling likely involves the bone loss process. It was hypothesized that the degree of bone mineralization (DBM) at AB region will be altered resulting from the active remodeling associated with periodontitis. The objective of this study was to examine if the DBM distribution is different between healthy and periodontitis AB regions in patients.         

Methods: After approval of IRB, clinical cone-beam computed tomography (CBCT) images obtained from 9 periodontitis patients (2 males and 7 females, mean 62.08 yrs) were identified from 350 patient CBCT database. Periodontitis was defined as clinical attachment loss greater than 3 mm around teeth. Bone voxels in CBCT images were segmented from non-bone voxels using a heuristic algorithm. The 3D AB region surrounding teeth was digitally isolated within 1 mm outside root surface. Three groups of AB region were identified including normal control and disease sub-regions of AB at the same disease tooth (DC and DD, respectively), and normal control AB region at another healthy tooth (CC). The DBM histogram was obtained by calibrating a CT attenuation value of each bone voxel to a mineral density using known phantoms. Mean, standard deviation (SD), and coefficient of variation (COV=SD/mean) of DBM were obtained. Paired t-tests were used for comparison.

Results: Mean of DBM between groups was not significantly different (1922 (DC), 1966 (DD), and 1939 (CC) mg/cm³, p>0.28). However, variability (SD and COV) of DBM was significantly different between DC and DD (p<0.001), while those between DC and CC were not different (p>0.77).

Conclusions: The DBM distribution of AB was altered by periodontitis. This finding suggested that clinical CBCT based DBM analysis can help understand how AB properties change in the progress of periodontal disease and improve diagnosis of periodontitis in patients.