Furcation involvement and tooth loss: A registry‐based retrospective cohort study

Aim This registry‐based retrospective cohort study aimed to evaluate the impact of furcation status on the risk for molar loss. Materials and Methods Subjects with and without furcation involvement (FI) in 2010/2011 were identified in a nationwide registry in Sweden (age‐ and gender‐matched sample: 381,450 subjects; 2,374,883 molars). Data on dental and periodontal status were extracted for the subsequent 10‐year period. Impact of FI (at baseline or detected during follow‐up) on molar loss (i.e., tooth extraction) was evaluated through multilevel logistic regression and survival analyses. Results FI had a significant impact on molar loss. FI degrees 2 and 3 resulted in adjusted risk ratios of 1.67 (95% confidence interval [CI] 1.63–1.71) and 3.30 (95% CI 3.18–3.43), respectively. Following the first detection of deep FI (degrees 2–3), estimated survival decreased by 4% at 5 years and 8% at 10 years. In addition to FI, endodontic status and probing depth were relevant risk factors for molar loss. Conclusions Furcation status had a clinically relevant impact on the risk for molar loss. Following first detection of deep FI, however, the decline in molar survival was minor.