The prevalence and alterations of furcation involvements 13 to 16 years after periodontal treatment.

The aim of this study was to evaluate the long term outcome of furcation involved molars in a population treated for periodontal disease. Initially, the study sample was 147 referred periodontal patients. Periodontal treatment consisted of oral hygiene instructions, supra- and subgingival scaling and periodontal surgery. After treatment 99 patients participated in a two year study on root caries. The patients got maintenance treatment every third to fourth month during 2 years. At the end of that study the patients were periodontally healthy and were referred back for supportive treatment to the referring dentist. Thirteen to 16 years after periodontal treatment 81 patients were still alive and 64 accepted a re-examination. At the start of the observation period the remaining 64 patients had in total 1537 teeth. During the 13 to 16 year follow up 217 teeth were lost. The number of molars at baseline was 361. The number of furcation involvement with different degrees were; 267 (0), 67 (I), 25 (II) and 2 (III) respectively. Totally 69 molars were lost during follow up. The proportion of molar loss according to the degree of furcation involvements 0 to III at baseline were 15%, 29%, 40% and 100% respectively. It was a significant greater risk of loosing an initially furcation involved molar than a single rooted tooth (p<0.0001). The risk of loosing an initially furcated molar increased with the degree of furcation involvement (degree I; p<0.05, degree II; p<0.01). In conclusion: During a long term observation period molars with furcation involvements are more frequently lost than not furcation involved molars. However, two thirds are still in function 13 to 16 years after treatment which indicate that molars with furcation involvements might survive long after periodontal treatment.