AimTo evaluate the clinical treatment effects of a glycine powder air-polishing or ultrasonic device on peri-implant mucositis. Materials and methodsThirty-seven patients with one implant diagnosed with peri-implant mucositis (probing depth 4mm (0.2N) and bleeding on probing (BOP) (primary outcome)) were randomly assigned to treatment with either glycine powder air-polishing (GPAP) or ultrasonic (US) debridement. Treatment was performed at baseline and at 3 and 6months. Professional supra gingival cleaning was performed at 9 and 12months. Oral hygiene instructions were reinforced at each visit. ResultsAt 12months there was a statistically significant reduction in mean plaque score, bleeding on probing and number of periodontal pockets 4mm within the treatment groups compared to baseline. The percentages of diseased sites were significantly reduced for both groups. ConclusionsTreatment with a glycine powder air-polishing or an ultrasonic device is effective in non-surgical treatment of peri-implant mucositis.