Long-term follow up after endodontic microsurgery :The changing patterns between one year and over four years’ follow up

Abstract

Many outcome studies for endodontic microsurgery were done in a period of approximately one-year. Controversy exists on whether the postoperative one-year observation results are maintained over longer follow up. The aim of this study is to examine and compare the post-surgical results of the endodontic microsurgery under two time frames, one-year follow up, and over four years after the surgery. We analyzed patterns of stability, healing, deterioration, and the causes of failure of microendodontic surgery.The clinical database of the Department of Conservative Dentistry at the College of Dentistry, Yonsei University in Seoul, Korea, was searched for patients with a history of endodontic microsurgery performed from 2004 to 2007 and evaluated clinically and radiographically at the point of one-year and over four years after endodontic microsurgery. All evaluations were performed using the Molven criteria and PAI scoring system. Among the 550 cases with endodontic microsurgery, 103 cases were included in this study. In Molven criteria, of 92 cases classified as success at one-year, 89 cases (96.7%) remained so, whereas 3 cases (3.3%) regressed to failure at long-term follow up. Conversely, of 11 cases regarded as failure at one-year, 3 cases (27.3%) progressed to success group. After long-term follow up, the failure group after one-year follow up did not become more healed or deteriorative than the success group. In PAI scoring system, of 94 cases classified as successful results (score 1-3) at one-year, 90 cases (95.7%) remained so at long-term follow up, whereas 4 cases (4.3%) regressed to failure results (score 4-5). Conversely, of 9 cases classified as failure results at one-year, 2 cases (22.2%) progressed to successful results. After long-term follow up, the failure group after one-year follow up did not become more healed than in the success group. On the other hand, the failure group after one-year follow up became more deteriorative than in the success group.In spite of limitations, through this study, we were able to conclude that long-term outcomes of endodontic microsurgery can be predicted by one-year outcomes. During the long-term period, PAI scoring system was more sensitive than Molven criteria in observation of healing pattern changes. However, clinically, the PAI scoring system and the Molven criteria did not show significant differences in assessing the success and failure of the endodontic microsurgery.