Salvi, G.E., Mischler, D.C., Schmidlin, K., Matuliene, G., Pietursson, B.E., Brägger, U., et al.

Aim: To investigate risk factors for the loss of multi-rooted teeth (MRT) in subjects treated for periodontitis and enrolled in supportive periodontal therapy (SPT).

Material and methods: A total of 172 subjects were examined before (T0) and after (T1) active periodontal therapy (APT) and following a mean of 11.5±5.2 (SD) years of SPT (T2). The association of risk factors with loss of MRT was analysed with multilevel logistic regression. The tooth was the unit of analysis.

Results: Furcation involvement (FI) = 1 before APT was not a risk factor for tooth loss compared with FI = 0 (p=0.37). Between T0 and T2, MRT with FI = 2 (OR: 2.92, 95% CI: 1.68, 5.06, p=0.0001) and FI = 3 (OR: 6.85, 95% CI: 3.40, 13.83, p<0.0001) were at a significantly higher risk to be lost compared with those with FI = 0. During SPT, smokers lost significantly more MRT compared with non-smokers (OR: 2.37, 95% CI: 1.05, 5.35, p=0.04). Non-smoking and compliant subjects with FI = 0/1 at T1 lost significantly less MRT during SPT compared with non-compliant smokers with FI = 2 (OR: 10.11, 95% CI: 2.91, 35.11, p<0.0001) and FI = 3 (OR: 17.18, 95% CI: 4.98, 59.28, p<0.0001), respectively.

Conclusions: FI = 1 was not a risk factor for tooth loss compared with FI = 0. FI = 2/3, smoking and lack of compliance with regular SPT represented risk factors for the loss of MRT in subjects treated for periodontitis.

J Clin Periodontol 2014; 41 (7): 701-707.