The influence of bone tissue deficiency on the outcome of endodontic microsurgery: A prospective study

Introduction: This study assessed the influence of deficiencies of the periapical and marginal bone tissue on clinical outcomes after endodontic microsurgery. Methods: Data were collected from the Microscope Center of the Department of Conservative Dentistry at the Dental College of Yonsei University, Seoul, South Korea, between August 2004 and March 2011. In total, 199 teeth that required endodontic surgery were included in the study. During the surgical procedure, deficiencies of the periapical and marginal bone tissue were measured immediately before the flap was repositioned. The patients were recalled 6 months and 1 year after the surgical procedure to assess the clinical and radiographic signs of healing. The Student's t test or the Mann-Whitney U test and logistic regression were performed to evaluate the parameters. Significant associations between the outcome and all the evaluation parameters were analyzed using the Pearson chi-square test or the Fisher's exact test with a significance level of 0.05. Results: A recall rate of 67.8% (135/199 teeth) was obtained. The height of the buccal bone plate was the only significant predictor (P =.040) of the healing outcome, suggesting that teeth with a buccal bone plate >3 mm presented a higher success rate than teeth with a buccal bone plate that was ≤3 mm high (94.3% vs 68.8%, P <.001). Conclusions: These data suggest that a favorable prognosis can be expected when teeth are covered with a buccal bone plate that is >3 mm in height regardless of the amount of marginal bone loss.