Nibali L, et al. - Authors evaluated the stability over time of periodontal intrabony defects treated with minimally invasive non-surgical therapy (MINST) and supportive periodontal therapy (SPT). They analyzed the baseline, 1- and 5-year radiographs, and compared the bone levels by multilevel linear regression adjusted by latent variable method. Findings suggested up to 5 years stablity of clinical and radiographic improvements in intrabony defects after MINST seen at 1 year, bringing evidence to support its long-term efficacy for the treatment of intrabony defects in non-smokers. For a bigger reduction in defect depth, deeper initial defects and narrower angles were predictive.