A number of other studies also report that leaving fragments of the instrument on the implant surface or scratching the surface may impede optimal peri-implant healing [17,18,19,20].

Chitosan is a marine biopolymer which is based on chitin derived from the shells of marine crustaceans. The material has been approved for use in surgical bandages, as a haemostatic agent and as a dietary supplement in a wide range of nutritional and health products. Chitosan has also been documented to be non-allergenic and may exhibit anti-inflammatory properties. The material is demonstrated to be completely biocompatible which also recently was verified in an animal experimental study [21]. In a pilot randomized split mouth clinical trial including 11 patients with mucositis, it was demonstrated that debridement with a chitosan device or titanium curettes lead to significant reduction in peri-implant mucositis. A better reduction in parameters of inflammation was however seen at 4 weeks at the implants treated with the chitosan device as compared with titanium curettes (Wohlfahrt et al. submitted for publication).

In the present study, the aim was to evaluate the effect on implant mucosal inflammation from the use of a novel instrument made of chitosan in the non-surgical treatment of mild peri-implantitis across several clinical centers.