Comparison of Two Different Surgical Approaches To Increase Peri-Implant Mucosa Thickness

Study Overview
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Brief Summary
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The purpose of this non-inferiority trial is to determine the clinical efficacy of acellular dermal matrix (ADM) in the augmentation of the gum around dental implants as compared to an autologous gum graft (sCTG) obtained from the palate (roof of the mouth) in human adults. AlloDerm is regulated by the US Food and Drug Administration (FDA) as human tissue for transplantation. AlloDerm is processed and marketed in accordance with the FDA's requirements for banked human tissue (21 CFR, Part 1270 and Part 1271) and Standards for Tissue Banking of the American Association of Tissue Banks (AATB). Twenty adult subjects will be recruited who are in need of dental implant placement with simultaneous gum grafting to increase the thickness of the facial mucosa. Half of the subjects will be randomized to the ADM group and half will be randomized to the sCTG group. The surgical intervention will be performed according to the protocol and subjects will return for follow-up 2, 4, 8, and 16 weeks post-surgery for follow-up measurements of healing, gum thickness, subject perception of pain, and esthetic photographs.

Detailed Description
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Although little is known about the influence of peri-implant mucosa thickness (PMT) on long-term biologic outcomes, soft tissue thickness is a critical component to esthetic dental implant restorations. While the subepithelial connective tissue graft (sCTG) has been recognized as the gold standard for gingival augmentation, several studies have reported acellular dermal matrix (ADM) may produce similar outcomes. Healthy patients with a thin biotype were selected on the basis of an eligibility criteria and randomized to the control (sCTG) or test (ADM) group. Measurements were completed by a masked examiner at baseline and at implant uncovering. Patient reported outcomes were recorded, as well. A power analysis suggested 20 subjects be recruited. The gain in PMT at 1mm, 3mm and 5mm from the expected CEJ and recipient site wound dehiscence were measured and recorded in both groups at different time points by a calibrated, masked examiner. Patient-related outcome measures (PROMs), such as pain and level of satisfaction with final outcome, were also recorded for all study participants.

Official Title
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Comparison of Two Different Surgical Approaches to Increase Peri-Implant Mucosa Thickness: A Randomized Controlled Clinical Trial

Conditions
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Tooth Loss, Peri-implant Mucosa Defect

Intervention / Treatment
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* Drug: Acellular Dermal Matrix
* Procedure: Autologous subepithelial connective tissue graft


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: Age: 18 to 80 years. Subjects must be able and willing to follow instructions related to the study procedures. Subjects must have read, understood and signed an informed consent form. At least one single-tooth edentulous site, with adjacent natural teeth, planned for tooth replacement therapy with an implant-supported restoration. Exclusion criteria: Reported allergy or hypersensitivity to any of the products to be used in the study. Severe hematologic disorders, such as hemophilia or leukemia. Active severe infectious diseases that may compromise normal healing. Liver or kidney dysfunction/failure. Currently under cancer treatment or within 18 months from completion of radio- or chemotherapy. Subjects with uncontrolled diabetes, defined as Hba1c > 6.5% (According to the American Diabetes Association 2014 Guidelines) Pregnant women or nursing mothers. Smokers: Subjects who have smoked within 6 months of study onset. Concomitant medications for systemic conditions that may affect the outcomes of the study. Any other non-specified reason that from the point of view of the investigators will make a candidate not a suitable subject for the study (e.g. limited mouth opening).

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Control<br>Autologous subepithelial connective tissue graft | Procedure: Autologous subepithelial connective tissue graft<br>* Placement of autologous subepithelial connective tissue graft on the buccal/coronal aspect of the alveolar ridge at the time of implant placement, following a two-stage approach<br>* Other names: sCTG;|
| Experimental: Experimental<br>Acellular Dermal Matrix | Drug: Acellular Dermal Matrix<br>* Placement of acellular dermal matrix (Alloderm®) on the buccal/coronal aspect of the alveolar ridge at the time of implant placement, following a two-stage approach<br>* Other names: Alloderm®;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Buccal Peri-implant Mucosa Thickness Between Baseline and 16 Weeks After Surgery | Buccal mucosa thickness measurements were obtained by a calibrated, masked examiner using a custom-made stent and an endo file for precision and reproducibility between different time points | Baseline and 16 weeks after baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in Peri-implant Keratinized Mucosa Width (Apico-coronal) at 16 Weeks After Surgery |  | Baseline to 16 weeks after baseline | 
| Patient-perceived Discomfort, Measured by VAS | Patient-reported outcome measures of perceived discomfort using a visual analog scale (VAS) from 0 (no pain) to 100 (maximum pain) were recorded | 2 weeks | 
| Wound Healing, Measured Using a Standardized Visual Wound Healing Index | Wound healing status was evaluated by the same calibrated clinician using a standardized visual wound healing index at different time points A simple wound healing scoring system including 3 categories was used: 1- uneventful wound healing, 2- slight gingival edema, erythema or discomfort, 3- poor wound healing | 2 weeks |