Factors influencing pocket closure in surgically-treated intraosseous defects. A retrospective analysis

Objectives: to evaluate the association between patient- and local- factors and pocket closure (i.e., probing depth, PD, ≤4 mm) following surgical treatment of intraosseous defects with the Single Flap Approach (SFA). Materials & methods: a retrospective analysis of data from previous studies was conducted on 101 defects treated with SFA alone or in combination with enamel matrix derivative with/without a bovine-derived xenograft. Pocket closure at 12 months was the primary outcome. Age, sex, smoking status, baseline PD, tooth type, depth of the supraosseous component, radiographic depth of the intraosseous component, defect angle, defect morphology, treatment modality were considered as candidate determinants in a bivariate logistic regression analysis. Backward stepwise regression was used to identify the optimal set of factors significantly associated with pocket closure. Results: 12-month pocket closure occurred in 74.3% of cases. The probability of pocket closure was significantly associated with baseline PD (OR = 0.741, 95%CI: 0.565-0.973; p = 0.031) and defect morphology, with defects classified as "mainly 1-wall" and "mainly 3-wall" showing greater odds for pocket closure compared to "mainly 2-wall" defects (OR = 7.125, p = 0.006; and OR = 5.225, p = 0.006, respectively). Conclusions: When performed according to the SFA, regenerative surgical procedures are associated with high probability of pocket closure at 12 months. Intraosseous lesions with deeper pre-surgery PD and/or prevalent 2-wall morphology have lower probability to be closed. Clinical relevance: Data from the present study may be of use to the clinician who wants to optimize the odds for pocket closure at a deep intraosseous lesion that is being approached according to the SFA.