Approximately two million new dental implants are inserted per year around the world and tens of millions of implants are still in use. Moreover, it is estimated that approximately 200,000–250,000 implants are removed every year. Peri-implantitis is the major cause of the implant retrieval and also the most common complication caused by implant surgery. Mombelli et al. reported that plaque formation can occur on dental implant surfaces similar to that of tooth surfaces.

The mainstay treatment for peri-implantitis includes the elimination of etiologic factors and the mechanical removal of calculus, cement, and plaque followed by subgingival irrigation with tetracycline and chlorhexidine base mouthwash. Lang et al. first described a treatment protocol for peri-implantitis including mechanical cleaning, decontamination of the implant surface, antibiotic regimen, and regenerative surgery (if required) in 1997. However, literate indicates that the use of air-powder abrasive (APA) treatment for the decontamination of the implant surface remains controversial. Although some reports advocate that the in vivo usage of APA systems pose a potential risk of emphysema and may have limited clinical applications, some other studies, such as the study reported by Duarte et al. found that APA is more effective in the decontamination of dental implants than lasers, metal curettes, and plastic curettes. On the other hand, Renvert et al. compared the use of APA and Er:YAG laser application on dental implant surfaces and found that the two methods produced similar outcomes with regards to the decontamination of implant surfaces. In the present study, we used a combination of APA and citric acid for the decontamination of the surfaces of the retrieved implants, mainly because both methods are easily available, have minimal cost, and are easy to use when compared to laser treatment.

Another controversy reported in the literature is concerned with the re-healing process around the contaminated implant surface. Although some studies contend that re-healing is possible around the dental implants affected by peri-implantitis depending on the implant surface treatment modalities employed prior to re-insertion, some other studies, such as the study reported by Persson et al. showed that they did not detect any re-osseointegration around the contaminated non-modified surface of the dental implants after the treatment of the implant surfaces affected by peri-implantitis. On the other hand, Hürzeler et al. detected re-osseointegration with guided bone regeneration, Persson et al. found re-osseointegration in 84% of SLA implants, and Alhag et al. showed re-osseointegration on plaque-covered implant surfaces after the removal of the plaque by means of citric acid, tooth brush, and hydrogen peroxide.