Defect angle as prognostic indicator in the reconstructive therapy of peri-implantitis

To analyze the influence of the characteristics of bone defects caused by peri-implantitis on the clinical resolution and radiographic bone gain following reconstructive surgery.

This is a secondary analysis of a randomized clinical trial. Periapical x-rays of bone defects, caused by peri-implantitis exhibiting intrabony component, were analyzed at baseline and 12-month follow-up after reconstructive surgery. Therapy consisted of anti-infective therapy along with a mixture of allografts with or without a collagen barrier membrane. The association of defect configuration, defect angle (DA), defect width (DW), and baseline marginal bone level (MBL) with clinical resolution (based on a prior defined composite criteria) and radiographic bone gain was correlated by means of generalized estimating equations.

Overall, 33 patients with a total of 48 implants exhibiting peri-implantitis were included. None of the evaluated variables yielded statistical significance with disease resolution. Defect configuration demonstrated statistical significance when compared to class 1B and 3B, favoring radiographic bone gain for the former (p = 0.005). DW and MBL did not demonstrate statistical significance with radiographic bone gain. On the contrary, DA exhibited strong statistical significance with bone gain (p < 0.001) in the simple and multiple logistic regression analyses. Mean DA reported in this study was 40°, and this resulted in 1.85 mm radiographic bone gain. To achieve ≥1 mm of bone gain, DA must be <57°, while to attain ≥2 mm of bone gain, DA must be <30°.

Baseline DA of peri-implantitis intrabony components predicts radiographic bone gain in reconstructive therapy (NCT05282667-this clinical trial was not registered prior to participant recruitment and randomization).