Surface Decontamination in Treatment of Peri-Implantitis

Peri-implantitis represents a major biological complication of implant dentistry with reported prevalence of up to 47% of implants. The disease is characterized by inflammatory response to the biofilm inhabiting the implant surface. To treat this inflammatory disease, surgical and non-surgical therapies have been proposed, all of which entail biofilm removal through implant surface decontamination. Systematic review of various surface decontamination protocols has failed to demonstrate superiority of any of the protocols. One possible explanation is that most studies have examined decontamination of implant surfaces following experimentally-induced peri-implantitis, where implant surfaces lack the tenacious mineralized biofilm often found in clinical peri-implantitis and are therefore easily decontaminated. The investigators have hypothesized that control of inflammation and repair of pathologically damaged peri-implant tissues requires a comprehensive mechanical plus chemical surface decontamination therapy. The aims of this study are to 1) determine the most effective surface decontamination protocol that can lead to control of peri-implant inflammation and 2) delineate the microbial and immunological mediators that are associated with the changes in peri-implant inflammation. The investigators propose to compare conventional implant surface contamination techniques to a comprehensive mechanical plus chemical protocol. This randomized controlled clinical trial seeks to enroll 68 participants with at least one implant diagnosed with moderate to severe peri-implantitis. Pre-op parameters to be assessed include: probing pocket depth, bleeding on probing, suppuration, plaque index, marginal inflammation, recession, clinical attachment level, inflammatory biomarkers and microbial sampling, and digital intra-oral peri-apical radiograph. Subjects will be randomly assigned to one of the four surgical debridement intervention groups: (A) gauzes soaked in sterile saline and chlorhexidine; (B) Titanium brush; (C) Air power abrasion; (D) comprehensive surface decontamination, including titanium brush, air powder abrasion and surface etching with 9.6% hydrofluoric acid gel. At 3-months post-operative, the initial clinical assessment will be repeated. The clinical examination will be used to analyze the efficacy of each treatment in controlling peri-implant mucosal inflammation. The ultimate objective of this research is not only to identify an effective method for control of peri-implant inflammation, but also to lay the foundation to detect biomarkers of peri-implantitis that can potentially be helpful in future studies as risk factors of this disease.

Implant surface will be wiped with sterile gauze soaked alternatively in sterile saline and CHX (5 times)

Titanium brush: Titanium brush (TiBrush, Straumann, Switzerland) mounted on an oscillating hand piece will be used for 1 minute.

Air powder abrasion: One minute of air powder abrasion using Glycine prophy powder (Prophy Jet, Dentsply, USA) with overlapping passes form apical to coronal direction for 1 minute.

A comprehensive treatment including the use of titanium brush and air powder abrasion (as described above) and 30 seconds etching with 9.6% HF acid gel (Premier, USA) applied with a micro-applicator tip (Unipack Medical, USA), followed by copious irrigation with sterile saline.

Implant surface will be wiped with sterile gauze soaked alternatively in sterile saline and CHX (5 times)

Titanium brush: Titanium brush (TiBrush, Straumann, Switzerland) mounted on an oscillating hand piece will be used for 1 minute.

Air powder abrasion: One minute of air powder abrasion using Glycine prophy powder (Prophy Jet, Dentsply, USA) with overlapping passes form apical to coronal direction for 1 minute.

A comprehensive treatment including the use of titanium brush and air powder abrasion (as described above) and 30 seconds etching with 9.6% HF acid gel (Premier, USA) applied with a micro-applicator tip (Unipack Medical, USA), followed by copious irrigation with sterile saline.

A periodontal probe will be used at 6 locations around each implant (mesiobuccal, buccal, distobuccal, mesiolingual, lingual, and distolingual). Presence of gingival bleeding upon probing will be recorded. This will be a binary outcome (Yes or No)

A periodontal probe will be used at 6 locations around each implant (mesiobuccal, buccal, distobuccal, mesiolingual, lingual, and distolingual). Presence of suppuration upon probing will be recorded. This will be a binary outcome (Yes or No)

Inclusion Criteria: PPD >6 mm Positive BOP Peri-implant marginal bone loss (MBL) >3 mm Age: 18 to 75 years Exclusion Criteria Implant mobility Smoking Current cancer Steroids use (last 2 years) Bisphosphonates use (last 4 years) Uncontrolled diabetes (HBA1c >7) Other systemic conditions that affect wound healing

At the end of the study, the clinical data and radiographs will be shared with other investigators included in this study for analysis.