Long‐term success and influencing factors of regenerative surgery for intra‐bony defects: A retrospective cohort study

BackgroundThe composite outcome measure (COM) more comprehensively assesses the clinical efficacy of regenerative surgery than a single probing measurement. We aimed to assess long‐term success defined by the COM (clinical attachment level [CAL] gain of ≥3 mm and postsurgery probing pocket depth [PPD] ≤ 4 mm) and influencing factors of regenerative surgery using bone substitutes and resorbable collagen membrane (RM) for intra‐bony defects (IBDs).MethodsWe retrospectively collected data from patients who underwent regenerative surgery using deproteinized bovine bone mineral (DBBM) and RM for IBDs. CAL and PPD values were compared at baseline (preoperative), 1 year (short‐term), and at the last follow‐up (5–10 years). Multivariate logistic regressions were performed to identify factors influencing COM‐based long‐term success.ResultsEighty‐one defects in 75 teeth of 33 patients who completed follow‐up (6.5 ± 1.4 years) were included. One tooth was lost. All defects with complete follow‐up exhibited long‐term average CAL gain (3.00 ± 2.00 mm, 95% confidence interval [CI]: 2.56–3.44 mm, p < 0.001) and PPD reduction (2.06 ± 1.91 mm, 95% CI: 1.64–2.49 mm, p < 0.001). Long‐term success was achieved in 38.8% of IBDs. CAL and PPD values were comparable between 1 year and the last follow‐up. Logistic regression analyses revealed that male sex (odds ratio [OR] = 0.23, 95% CI: 0.07–0.75) and bleeding on probing (BOP) during supportive periodontal therapy (OR = 0.96, 95% CI: 0.94–0.99) were risk factors for long‐term success.ConclusionsRegenerative surgery with DBBM and RM for IBDs can achieve some degree of long‐term success defined by COM. However, within this study's limitations, male sex and higher BOP incidence postoperatively are negatively associated with optimal long‐term success.Clinical trial numberChiCTR2300069016.