Treatment of Peri-implantitis With or Without Simultaneous Soft Tissue Augmentation

Study Overview
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Brief Summary
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The study will aim to compare two modalities in the reconstructive treatment of peri-implantitis defects. More specifically, the control group will be a reconstructive approach (xenograft bone graft granules and collagen membrane, BioOss and BioGide, Geistlich, Wolhusen). The test group will be the same with the exception of an autologous sub-epithelial connective tissue palatal graft, sutured beneath the flap, which will be used in addition to grafting materials. Outcomes will include CAL, PD, MR, defect resolution, PI, BoP, SUPP, patient-reported outcome measures including an aesthetic self-evaluation.

Detailed Description
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The study will aim to compare two modalities in the reconstructive treatment of peri-implantitis defects. More specifically, the control group will be a pure reconstructive approach (xenograft bone graft granules and reservable collagen membrane, BioOss and BioGide, Geistlich, Wolhusen). This is in accordance with gold standard practices of reconstructive therapy of peri-implant defects. The test group will be treated with the same approach and materials, with the exception of an autologous sub-epithelial connective tissue palatal graft, sutured beneath the flap, which will be used in addition to the grafting materials. The graft will be harvested from the homolateral palate (molar region). Outcomes will include CAL, clinical attachment level (primary outcome), PD or probing depth, MR or mucosal recession, defect resolution (composite outcome made up of simultaneous absence of PD>5 mm, BOP/SUP and bone level changes >0.5 mm, PI, BoP or bleeding upon probing, suppuration SUP on probing, SUP on palpation, patient-reported outcome measures including an aesthetic self-evaluation. The measures will be recorded at baseline, 6-, 12-, 18- and 24 months. Radiographic bone levels will be compared with 2 week image at 12 and 24 months

Official Title
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Surgical Reconstructive Treatment of Peri-Implantitis With or Without Simultaneous Soft Tissue Augmentation: a Multi-center Randomized Controlled Trial

Conditions
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Peri-Implantitis

Intervention / Treatment
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* Procedure: Peri-implantitis reconstructive surgery


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: · Be able and willing to provide consent and sign the informed consent form. Be able and willing to comply with study procedures and follow-up appointments required by the study protocol. Age>18 years Presence of at least one implant affected with peri-implantitis, defined as the following con-dition: at least one site presenting peri-implant probing depth (PPD) >6 mm and simultane-ous presence of profuse BoP/SUP and a radiographically documented change in bone level greater than initial bone remodeling. In the likely event that a baseline radiographic image is absent, the bone level will be compared to where it would likely have been at the time of implant insertion and a difference of >3 mm from that level will be considered. Implants in function (i.e. loaded) for at least 1 year. Screw- and cement-retained suprastructures for both fixed and removable prostheses. Exclusion Criteria: Compromised systemic health which contraindicates the study procedures. Pregnant or nursing women. Cigarette smoking>5 per day Systemic conditions compromising healing (i.e. diabetes mellitus). Patients with diabe-tes mellitus types I or II will be asked to provide information regarding their most re-cent HbA1c values. Only patients with HbA1c<7% will be enrolled. Patients taking medications known to interfere with gingival or bone metabolism.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Xenograft+collagen membrane<br>Reconstructive approach (Xenograft+collegen membrane) | Procedure: Peri-implantitis reconstructive surgery<br>* For both arms (excluding the already included information): defect debridement, removal of debris using titanium curettes, titanium brushes on the implant surface, irrigation with saline, application of sterile cotton pellets with saline solution. Grafting with (experimental) xenograft and soft tissue, or xenograft alone (control). Suture. Specific to control group (active comparator): the peri-implant defect will be filled with xenograft, and a collagen membrane will be fitted and trimmed to the defect area. Specific to test/experimental group: same as above (for control). In addition a soft tissue graft will be harvested from the palate and sutured to the buccal flap. The entire flap will then be sutured to the lingual flap.<br>|
| Experimental: Xenograft+collagen membrane+autologous soft tissue graft<br>Reconstructive approach (Xenograft+collegen membrane) plus soft tissue graft (autologous, harvested as FGG) | Procedure: Peri-implantitis reconstructive surgery<br>* For both arms (excluding the already included information): defect debridement, removal of debris using titanium curettes, titanium brushes on the implant surface, irrigation with saline, application of sterile cotton pellets with saline solution. Grafting with (experimental) xenograft and soft tissue, or xenograft alone (control). Suture. Specific to control group (active comparator): the peri-implant defect will be filled with xenograft, and a collagen membrane will be fitted and trimmed to the defect area. Specific to test/experimental group: same as above (for control). In addition a soft tissue graft will be harvested from the palate and sutured to the buccal flap. The entire flap will then be sutured to the lingual flap.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Clinical attachment level | linear distance (mm) from the implant platform to the bottom of the pocket | change from baseline to: 6, 12, 18, 24 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Probing depth | linear distance (mm) from the gingival margin to the bottom of the pocket | 6, 12, 18, 24 months | 
| Disease resolution | No PD greater than or equal to 5 mm and simultaneous absence of BOP/SUP and no more than 0.5 mm change between 2 weeks and 12 and 24 months on radiograph | 6, 12, 18, 24 months | 
| Mucosal recession | linear distance (mm) from the implant platform to the gingival margin | 6, 12, 18, 24 months | 
| plaque index (minimum value 0, maximum 1) | binary outcome: yes/ no detected running the probe into the peri-implant sulcus | 6, 12, 18, 24 months | 
| profuse bleeding | abundant bleeding evoked upon probing immediately after | 6, 12, 18, 24 months | 
| BOP | bleeding upon probing: bleeding evoked upon probing after 1 second | 6, 12, 18, 24 months | 
| suppuration | Binary: yes or no, detected upon probing or digital palpation | 6, 12, 18, 24 months | 
| Gingival thickness | Measured in a horizontal direction at 1 mm from the gingival margin | 6, 12, 18, 24 months | 
| Patient-reported outcome measures | pain-bleeding-aesthetic self-evaluation-swelling-discomfort | 6, 12, 18, 24 months | 
| Radiographic bone levels | radiographic bone level changes between the 2 week and 12 and 24 month follow-ups | 2 weeks, 12 months, 24 months |