Regenerative Treatment of Peri-implantitis

Study Overview
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Brief Summary
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The purpose of this study is to study the use of a new type of d-PTFE membrane called reinforced PTFE Mesh (RPM) with dental surgery. The regenerative outcomes of RPM membranes and collagen membrane for surgical reconstructive treatment of peri-implantitis (gum disease around implants) will be compared.

Detailed Description
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Peri-implantitis is an inflammatory response that leads to irreversible loss of implant supporting bone. This study will investigate the regenerative outcomes obtained with two membranes for surgical reconstructive treatment of peri-implantitis defects when the implant is submerged and primary wound closure is obtained. In one group the newly designed d-PTFE membrane with macropores, known as the RPM membrane will be utilized, which will be compared to the traditional collagen membrane used in the other group. The clinical, radiographic, and histologic outcomes for the regenerative treatment of peri-implantitis when utilizing the same bone graft in combination with either a collagen membrane or the RPM will be evaluated via a parallel-arm randomized controlled clinical trial. 32 patients with peri-implantitis will be recruited and randomized to receive peri-implantitis treatment with either a collagen membrane or an RPM membrane.

Official Title
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Regenerative Treatment of Peri-implantitis: A Comparison of the Reinforced PTFE Mesh (RPM) and the Collagen Membrane in the Submerged Approach: a Randomized Controlled Clinical Trial

Conditions
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Peri-Implantitis

Intervention / Treatment
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* Procedure: Membrane placement with bone grafting


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 18 years Physical status according to the American Society of Anesthesiology (ASA) I or II, which include patients who are systematically healthy or may suffer from mild to moderate, however well-controlled systemic diseases. Subjects having at least one dental implant with peri-implantitis according to the definition proposed by the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions (Berglundh et al., 2018): Full-mouth plaque score and full-mouth bleeding score ≤ 20% (measured at four sites per tooth) Correct 3-dimensional implant positioning, or buccal position ≤ 1 mm Implants which have been in function for at least 6 months Exclusion Criteria: A clearly mal-positioned dental implant Significant interproximal horizontal bone loss (more than 50% of implant fixture length) A mobile dental implant Presence of uncontrolled or untreated periodontal disease More than 2 weeks usage of antibiotics in the past two months Subjects taking medications known to modify bone metabolism or those that can interfere with the normal wound healing (such as bisphosphonates, corticosteroids, hormone replacement therapy, parathyroid hormone, denosumab, strontium ranelate, etc.), or those with uncontrolled systemic diseases or conditions that may similarly affect the patient's healing (osteoporosis, osteopenia, hyperparathyroidism, Paget's disease, uncontrolled diabetes (HBA1c > 8)). Pregnant subjects or individuals attempting to get pregnant (self-reported) Subjects smoking more than 10 cigarettes a day, or those with a history of drug or alcohol abuse (self-reported) Subjects unable to maintain adequate oral hygiene (O'Leary plaque index more than 50%) (O'Leary et al., 1972) Any other contraindications for undergoing periodontal surgery

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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No

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 |
| --- | --- |
| Experimental: PTFE Mesh Membrane<br>A reinforced PTFE Mesh membrane will be used to cover the bone graft. | Procedure: Membrane placement with bone grafting<br>* The diseased dental implant will be cleaned and the bone defect will be filled with bone graft and covered by a membrane.<br>|
| Active Comparator: Collagen membrane<br>A collagen membrane will be used to cover the bone graft. | Procedure: Membrane placement with bone grafting<br>* The diseased dental implant will be cleaned and the bone defect will be filled with bone graft and covered by a membrane.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Probing depth measurements in millimeters | To compare probing depth measurements using a periodontal probe after peri-implantitis treatment | About 5 weeks before baseline surgery and at 8.5 months after baseline surgery. | 
| Bone measurements in millimeters | Bone measurements obtained from CBCT | Baseline and 8 months after baseline surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Clinical attachment levels in millimeters | To compare clinical attachment measurements using a periodontal probe from baseline to the final follow-up visit | 8 months after baseline surgery | 
| Marginal bone levels in millimeters at the implant site | To compare marginal bone measurements from periapical radiographs | 8 months after baseline surgery | 
| Volumetric changes of grafted area in cubic millimeters | To compare volumetric bone measurements of the grafted areas from CBCT | 8 months after baseline surgery |