Evaluation of the effect of tooth vitality on regenerative outcomes in infrabony defects

Background, aims. This investigation was designed to evaluate the null hypo thesis of no differences in GTR outcomes in intrabony defects at vital and successfully root-canal-treated teeth. Method: 208 consecutive patients with one intrabony defect each were enroll ed. Based on tooth vitality, the treated population was divided at baseline into 2 groups: one with 41 non-vital teeth and the other with 167 vital te eth. The 2 groups were similar in terms of patient and defect characteristi cs. Results: A slight unbalance in terms of depth of the intrabony component wa s observed in the non-vital group compared to the vital group (6.9 +/-2.1 n m versus 6.2 +/-2.3 mm, p=0.08). All defects were treated with GTR therapy. At 1 year, the non-vital and the vital groups showed a clinical attachment level (CAL) gain of 4.9 +/-2.2 mm and of 4.2 +/-2 mm, respectively. The di fference was statistically significant (p=0.03). To correct for the baselin e unbalance in defect depth, data were expressed as a % of clinical attachm ent level gains with respect to the original intrabony depth of the defect. % CAL gains were 72.8 +/- 42.2% and 73 +/- 26.4% for vital and non-vital t eeth, respectively: the difference was not statistically significant (p=0.4 8). Average residual pocket depths were 2.8 +/-1 mm in the vital and 2.8 +/ -0.9 mm in the non-vital group. Tooth vitality was assessed at baseline, at 1-year and at follow-up (5.4 +/-2.8 years after surgery): all teeth vital at baseline were still vital at follow-up with the exception of 2 teeth tha t received endodontic treatment for reconstructive reasons and for caries. At follow-up visit, the difference in CAL with respect to 1-year measuremen ts was -0.9 +/-0.8 mm in the vital group and -0.7 +/-0.8 mm in the non-vita l group, indicating stability of the regenerated attachment at the majority of sites. Conclusions: Data from this study demonstrate that root canal treatment doe s not negatively affect the healing response of deep intrabony defects trea ted with GTR therapy; furthermore GTR therapy in deep intrabony defects doe s not negatively influence tooth vitality.