Augmentation of Keratinized Tissue Around Dental Implant With a Xenogeneic Collagen Matrix and the Free Gingival Graft

Study Overview
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Brief Summary
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The purpose of this study is to compare the clinical effects of combined application of combined application of a xenogeneic collagen matrix and the free gingival graft in augmentation of keratinized tissue around dental implant by single arm clinical trial, compared with historical control group 1:application of a xenogeneic collagen matrix,and historical control group 2:application of the free gingival graft.

Detailed Description
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The purpose of this study is to compare the clinical effects of combined application of a xenogeneic collagen matrix and the free gingival graft in augmentation of keratinized tissue around dental implant by single arm clinical trial, compared with historical control group 1:application of a xenogeneic collagen matrix,and historical control group 2:application of the free gingival graft. This study designed a single arm clinical trial. The included patients will all be treated with apical repositioned flap with a xenogeneic collagen matrix and the free gingival graft. The width of keratinized mucosa, thickness of keratinized mucosa, gingival index, probing depth will be measured before surgery and at 2, 6 months postoperatively.

Official Title
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Augmentation of Keratinized Tissue Around Dental Implant With Combined Application of a Xenogeneic Collagen Matrix and the Free Gingival Graft : a Single Arm Clinical Trial

Conditions
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Inadequately Attached Gingiva

Intervention / Treatment
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* Procedure: apically repositioned flap+ xenogeneic collagen matrix +free gingival graft


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged >=18 years and periodontally and systemically healthy; Presence of at least one site with <=2 mm of keratinized tissue; associated with a shallow vestibule in the edentulous region after implant surgery (no more than three consecutive implants); Need of keratinized tissue augmentation for aesthetic purpose and/or functional reasons; Full mouth probing depths <=5mm; Full-mouth plaque score (FMPS) and full-mouth bleeding score (FMBS) <=15%; Be able to comply with all procedures related to the study. Exclusion Criteria: Smoking; Pregnant or lactating women; Untreated periodontal disease; Presence of systemic disorders (diabetes, heart disease, tumor or any other condition that could contraindicate periodontal surgery); Use of medications (immunosuppressants, phenytoin, or anything else that might affect mucosal healing and repair); Under radiotherapy; Allergy to the collagen; Previous mucogingival surgery in the area.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 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
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: strip<br>apically repositioned flap+ xenogeneic collagen matrix +free gingival graft | Procedure: apically repositioned flap+ xenogeneic collagen matrix +free gingival graft<br>* Harvest a strip free gingival graft from the palate, then place it above apically repositioned flap and fix xenogeneic collagen matrix to the recipient bed<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| change from baseline keratinized mucosa width at 2 and 6 months | measured from the mucogingival junction to the mucosa margin or the zenith of alveolar ridge at the mid-buccal aspect of each implant using a periodontal probe (UNC15) | baseline, at 2,6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| change from baseline keratinized mucosa thickness at 2 and 6 months | measured at the middle point of an apical-coronal direction at the mid-buccal aspect using an endodontic file with a rubber stop | baseline, at 2,6 months | 
| change from baseline Gingival index at 2 and 6 months | assessed at four gingival sites of each implant (mesio-labial/buccal, mid-labial/buccal, disto-labial/buccal, and palatal/lingual) . Indicated by numbers, 0: normal gingiva; 1: slightly edematous gingiva that does not bleed on probing; 2: edematous gingiva that bleeds on probing; 3: gingiva that has a tendency to bleed spontaneously or ulcerate. | baseline, at 2,6 months | 
| change from baseline probing depth at 2 and 6 months | measured at six sites of each implant (mesio-labial/buccal, mid-labial/buccal, disto-labial/buccal, mesio-palatal/lingual, mid-palatal/lingual, and disto-palatal/lingual) using a periodontal probe (UNC15) | baseline, at 2,6 months | 
| Post-operative pain | evaluated using a visual analog scale (VAS) ranging from 0 to 10 (0 = no pain and 10 = worst pain imaginable) | at 1 week after surgery | 
| change from 2 months patient satisfaction at 6 months | using a visual analog scale (VAS) ranging from 0 to 10 (0 = extremely dissatisfied and 10 = extremely satisfied) | at 2 and 6 months post operation | 
| dosage of postoperative analgesic drugs | dosage of postoperative analgesic drugs that patients take after surgery | at 1 week after surgery | 
| operation time | measured from the start of the first incision to the end of the last suture | during the surgery | 
| esthetic score | assessed by judging on the colour, contour, and texture of the surgical sites | at 6 months post operation | 
| change from baseline depth of recession at 2 and 6 months | The distance from the implant margin to the gingival margin was measured with a periodontal probe | baseline, at 2,6 months | 
| change from baseline width of recession at 2 and 6 months | The proximal and distal level of soft tissue retraction at the top of implant was measured by periodontal probe | baseline, at 2,6 months |