The chitosan brush used in this study is made of a material that is soft with the aim to make a device optimized for removal of the biofilm within the implant threads. The soft bristles on the contrary make the device suboptimal for removal of hard deposits, such as calculus and cement remnants. It has been reported that such cement remnants are a common finding around dental implants [41], and in hindsight, it would have been beneficial for the analysis to record this. We did not record or analyse on cement- or screw-retained supraconstructions, and it may well be that some of the implants with cement-retained crowns and bridges had subgingival and non-visible cement remnants contributing to the mucosal inflammation. It can thus be hypothesized that combining the brush with an instrument for the removal of potential hard deposits would have yielded even better results. One such instrument for surgical use on titanium surfaces is a rotating titanium brush. The disadvantage with such a rigid metal brush is that the metal bristles may potentially cause injure to the mucosa if used non-surgically. Once active peri-implantitis treatment is finished with a positive response verified and the long-term and regular supportive treatment phase initiated, it could be argued that avoiding instruments that may damage the implant surface is preferable [15]. The consecutive case series presented here does only show the potential merits of a chitosan brush on reducing peri-implant mucosal inflammation. No control group was included in this study, and to test the clinical efficacy of this novel device in the non-surgical treatment of peri-implantitis, a randomized clinical trial will be required. It is also important with a long-term follow-up to study if the use of this novel device will prevent progression of peri-implant bone loss over time, potentially causing implant loss.