https://www.selleckchem.com/products/tl12-186.html To date, scarce evidence exists around the application of subgingival air polishing during treatment of severe periodontitis. The aim of this study was to evaluate the benefits of subgingival air polishing during non-surgical treatment of deep bleeding pockets in stages III-IV periodontitis patients MATERIALS AND METHODS Forty patients with stages III-IV periodontitis were selected, and pockets with probing depth (PD) 5-9mm and bleeding on probing (BoP) were selected as experimental sites. All patients underwent a full-mouth session of erythritol powder supragingival air polishing and ultrasonic instrumentation. Test group received additional subgingival air polishing at experimental sites. The proportion of experimental sites shifting to PD ≤ 4 mm and no BoP at 3months (i.e., non-bleeding closed pockets, NBCPs) was regarded as the primary outcome variable. The proportion of NBCP was comparable between test and control group (47.9 and 44.7%, respectively). Baseline PD of 7-9 mm, multi-rooted teeth and the presence of plaque negatively influenced the probability of obtaining NBCP. The additional application of subgingival air polishing does not seem to provide any significant clinical advantage in achieving closure at moderate to deep bleeding pockets in treatment of stages III-IV periodontitis patients. The study was registered on Clinical Trials.gov (NCT04264624). While air polishing can play a role in biofilm removal at supragingival and shallow sites, ultrasonic root surface debridement alone is still the choice for initial treatment of deep bleeding periodontal pockets. While air polishing can play a role in biofilm removal at supragingival and shallow sites, ultrasonic root surface debridement alone is still the choice for initial treatment of deep bleeding periodontal pockets. To evaluate the performance of visual inspection alone and associated to radiographic and laser fluorescence (LF) methods in detecting