The potential associations of periapical lesions on endodontic microsurgery with guided bone regeneration: a retrospective analysis of 23 cases.

OBJECTIVE: This single-center, retrospective study analyzed the histological and radiographic changes of periapical lesions, evaluated healing outcomes after endodontic microsurgery combined with guided bone regeneration, and explored the preliminary factors associated with these outcomes. METHODS: All records were reviewed to identify patients treated by EMS with GBR at the Shenzhen Maternity and Child Healthcare Hospital between 2022 and 2026. The periapical tissues were stained with hematoxylin and eosin for morphologic and histopathological analysis. Preoperative and follow-up radiographic changes were calculated using Mimics software according to the PENN 3D criteria for three-dimensional (3D) healing. Survival and their preliminary factors were analyzed using logistic regression, and odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. RESULTS: A total of 23 patients (23 teeth) met the criteria for radiographic periapical healing analysis and were included in the survival analysis at 12-month follow-up. The histopathological images primarily demonstrate seven cases of periapical granuloma and 16 cases of radicular cyst. 3D reconstruction in Mimics effectively visualized periapical radiographic changes by enhancing the intuitiveness and reliability of outcome analysis. The overall radiographic periapical healing rate was 78.26%, and it was significantly associated with the gray values of periapical lesions (p: 0.023; OR: 0.091; 95% CI: 0.011-0.717) and deep overbite/overjet parameters of malocclusion (p: 0.035; OR: 0.071; 95% CI: 0.006-0.834). CONCLUSION: The gray values and increased overbite/overjet parameters of malocclusion may be considered potential univariate associations in the preliminary analysis, as 3D reconstruction in Mimics effectively visualized periapical radiographic changes. Meanwhile long-term follow-up studies of additional cases are still required to confirm these conclusions.