Furcation: the truth behind the roots!!!

Abstract

Background: Complex anatomic morphology of bifurcations and trifurcations predisposes multirooted teeth to plaque accumulation leading to periodontal infection. This poses a great difficulty in treatment planning and management of these furcation defects.Assessing the degree of furcation involvement depending on external tooth surface points may lead to the underestimation of positive treatment outcomes. Aim: To determine the buccolingual width of the furcation of mandibular molar and compare it with buccolingual width of mesial and distal roots at the level of root separation. Materials and Methods: 40 randomly selected mandibular molars were analyzed in which 20 first molars and 20 second molars were included. Four horizontal buccolingual distances were evaluated: CEJ, Furcation entrance/ roof width (FE), Mesial root width (MRW), andDistal root width (DRW).Discrepancies between FE measurements and MRW, DRW, and CEJ were determined in each tooth by subtracting the FE measurements respectively from MRW, DRW, and CEJ. Results: The width of the furcation entrance has a mean of 5.41 ± 0.67 mm varying from 4 to 7 mm in first molars and a mean of 5.18 ± 0.64 mm varying from 4 to 6 mm in second molars. In this study, the FE is measured more internally than the mesial and distal root surfaces and therefore, the FE is smaller than MRW and DRW.From this, it is evident that the actual furcation width is much less than the CEJ width, MRW and DRW measured buccolingually. Conclusion: Clinical measurements of horizontal probing depth that use the external surfaces of roots as reference points overestimate the true anatomical component of furcation involvement in mandibular molars. Conversely, positive treatment outcomes in these teeth may be underestimated.Thus, estimation of actual furcation entrance width before a surgical intervention is necessary and can influence the prognosis of involved teeth after different regenerative therapies for furcation defects. Key words : Furcation therapy, molar anatomy, periodontal attachment loss/diagnosis, outcome assessment of regenerative therapies.