Tooth-Related Risk Factors for Bone Loss During Periodontal Maintenance

Objectives: To analyze tooth-related risk factors from radiographic data of mild-moderate periodontal maintenance (PM) patients with or without interproximal bone loss.
Methods: Bitewing radiographs of periodontal maintenance patients were taken before and after at least two years of periodontal maintenance. Progressive periodontitis (PP) patients (with at least one site of posterior interproximal bone loss ≥2mm) and periodontitis stable (PS) patients (no sites with bone loss) were matched by age and gender and compared for measurements including: CEJ to alveolar crest length, overhanging restorations >2mm, distance of restoration margin to bone crest, interproximal contact to alveolar crest length, CEJ to alveolar crest length on adjacent tooth, width of interproximal (ITP) embrasure measured from CEJ to adjacent CEJ, and subcontact angle (angle formed between alveolar crest to interproximal contact and adjacent tooth alveolar crest). 71 individuals were in each group. Fisher's exact test and Wilcoxon Rank Sums test were used to compare groups.
Results: At baseline, the PP group had less CEJ to bone measurement (p<.0001), and more interproximal width (p=0.0016) and open contacts (p=0.05) than the PS group. The other tooth-related factors measured were not significantly different.
Conclusions: Increased interproximal width and open contacts may be risk factors that increase the likelihood of losing interproximal bone during periodontal maintenance, and restoration of open contacts/embrasures should be considered.