INTRODUCTIONrnSince the introduction of the concept of osseointegration by Branemark et al.,1 the use of endosseous dental implants for rehabilitation of missing teeth has become a routine treatment option. However, implant-related complications are frequently being reported and failures do occur. Peri-implantitis is a plaque-associated pathological condition occurring in tissues around dental implants, characterized by inflammation in the peri-implant mucosa and subsequent progressive loss of supporting bone,2 with an estimated prevalence of 22％, with reports up to 47％.3 Although plaque is the main etiologic factor in both peri-implantitis and periodontal disease, there are many differences between the two disease entities. Bone loss progresses more rapidly around dental implants compared to natural teeth, and often continues even after the etiology is removed.