Aim To compare the efficacy of two different therapies (amino acid glycine abrasive powder and a desiccant material) and their combination in the non‐surgical treatment of peri‐implantitis. Materials and Methods This was an examiner‐blind randomized clinical trial, with 2‐factorial design with a follow‐up of 6 months. The combination of the two factors resulted in four interventions: (a) non‐surgical debridement alone (C); (b) non‐surgical debridement and a desiccant material (H); (c) non‐surgical debridement and glycine powder (G); and (d) non‐surgical debridement, desiccant material and glycine powder (HG). Results Sixty‐four patients with peri‐implantitis were randomized, 16 for each intervention. After six months, two implants failed in the G intervention. Mean pocket depth reduction was higher in patients treated with the desiccant material (estimated difference: 0.5 mm; 95% CI from 0.1 to 0.9 mm, p = .0229) while there was no difference in the patients treated with glycine powder (estimated difference: 0.1 mm; 95% CI from −0.3 to 0.5 mm, p = .7333). VAS for pain during intervention and VAS for pain after one week were higher for patients treated with glycine powder (p = .0056 and p = .0339, respectively). The success criteria and other variables did not reveal differences between interventions. Conclusions In this 6‐month follow‐up study, pocket reduction was more pronounced in patients using the desiccant material. Pain was higher in patients using glycine. All the interventions resulted in low success rate.

The inter-rater agreement in the diagnosis of peri-implant disease was qualified as merely good. This could also be due in part to the unclear definition of peri-implantitis and mucositis.

Peri-implant bleeding was associated with site-specific factors.