Buccal Graft + Collagen Matrix Versus Free Gingival Graft for Keratinized Mucosa Augmentation at Implant Sites (FGGvsBSG+CM)

Buccal Strip Gingival Graft With a Xenogeneic Collagen Matrix Versus Free Gingival Graft for Keratinized Mucosa Augmentation at Implant Sites: A Randomized, Controlled, Clinical Trial

The study aims at comparing two different approaches for soft tissue augmentation at implants lacking keratinized and adherent mucosa width: the free gingival graft (FGG) vs the Buccal Strip Graft in combination with a xenogeneic collagen matrix (BSG + CM)

Study Overview

• Status: Active, not recruiting
• Conditions: Surgery
• Intervention / Treatment: Procedure: Conventional Free Gingival Graft Approach (FGG); Procedure: Buccal Strip Graft with a collagen matrix (bSG + CM)

Detailed Description

Conventional free gingival graft (FGG), serving as control group, will be compared to buccal strip gingival graft (BSG) in combination with a collagen matrix (CM), serving as test group, in terms of clinical, volumetric, ultrasonographic, and patient-reported outcomes related to soft tissue augmentation at implant sites lacking keratinized and adherent mucosa.

• Study Type: Interventional
• Enrollment (Actual): 32
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Massachusetts
    • Boston, Massachusetts, United States, 02115
      • Harvard School of Dental Medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Age ≥ 18 years,
• Periodontally and systemically healthy,
• Full-mouth plaque score and full-mouth bleeding ≤ 20% (measured at four sites per tooth),
• Presence of at least one dental implant with < 2 mm of KM and lack of firm/adherent mucosa,
• Presence of at least 4 mm of keratinized gingiva in two or more teeth nonadjacent to the implant to be treated,
• Implants diagnosed as healthy (Berglundh et al. 2018),
• The patient must be able to perform good oral hygiene.

Exclusion criteria:

• Contraindications for surgery,
• Systemic condition (e.g. diabetes mellitus, HIV, cancer, etc) that could compromise wound healing,
• Patients pregnant or attempting to get pregnant (self-reported),
• Untreated periodontitis,
• Untreated peri-implant mucositis or peri-implantitis (Berglundh et al. 2018),
• Smoking,
• Allergy to collagen-based medical products or iodine,
• Previous free gingival graft procedure at the target site.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Free gingival graft (FGG); Conventional free gingival graft, involving the harvesting of an epithelialized graft from the hard palate, which is then stabilized/sutured to the recipient site (implant).	Procedure: Conventional Free Gingival Graft Approach (FGG); Conventional Free Gingival Graft Approach involving palatal soft tissue harvesting
Experimental: Buccal Strip Graft + Collagen matrix (bSG + CM); Strip graft obtained from the buccal mucosa of a site showing abundant keratinized gingiva, combined with a collagen matrix. The bSG + CM graft is stabilized/sutured to the recipient site (implant).	Procedure: Buccal Strip Graft with a collagen matrix (bSG + CM); A small strip of keratinized gingiva is harvested from the buccal gingiva of a site showing abundant keratinized gingiva, and combined with a xenogeneic collagen matrix

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Sites showing KM≥ 2 mm and AM≥ 1 mm	Number of sites showing at least 2 mm of keratinized mucosa width (in millimeters) and at least of 1 mm of attached mucosa (in millimeters) (outcome expressed as a number)	6 and 12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Post-operative morbidity	Patient-reported outcome assessed using a daily questionnaire first the first 4 weeks (expressed as a number using a 0-100 visual analogue scale [VAS])	Daily, for the first 4 weeks after the procedure
KM width gain	Gain in keratinized mucosa width obtained after the intervention compared to baseline (expressed in millimeters)	6 and 12 months
AM gain	Gain in attached mucosa width obtained after the intervention compared to baseline (expressed in millimeters)	6 and 12 months
Mucosal thickness (MT) gain	Gain of mucosal thickness (MT) obtained after the intervention compared to baseline (expressed in millimeters)	6 and 12 months
Volumetric change	Volumetric change occurring at the treated sites analyzed by superimposing digital impressions obtained using optical scanners at baseline and 6 months (expressed in mm^3)	6 and 12 months
Ultrasonographic tissue perfusion	Tissue perfusion changes over the healing assessed with ultrasonography (expressed in cm/s)	Baseline, 1 week, 2 weeks, 1 month, 3 months, 6 months and 12 months
Treatment satisfaction	Patient-reported outcome assessed with questionnaire including a 0-100 visual analogue scale (VAS) at the last visit (expressed as a number)	12 months
Esthetic assessment	Patient-reported outcome assessed with questionnaire including a 0-100 visual analogue scale (VAS) at the initial and last visit (expressed as a number)	Baseline and 12 months
Ultrasonographic strain elastography	Changes in the elasticity of the soft tissue over the healing assessed with ultrasonography (expressed as a ratio)	Baseline, 3 months, 6 months and 12 months

Collaborators and Investigators

• Sponsor: Harvard Medical School (HMS and HSDM)
• Collaborators: Osteology Foundation
• Investigators: Principal Investigator: Lorenzo Tavelli, DDS, MS, PhD, Harvard School of Dental Medicine, Boston, USA

Study record dates

Study Major Dates

• Study Start (Actual): April 13, 2023
• Primary Completion (Estimated): September 21, 2025
• Study Completion (Estimated): December 21, 2025

Study Registration Dates

• First Submitted: April 5, 2023
• First Submitted That Met QC Criteria: April 25, 2023
• First Posted (Actual): May 6, 2023

Study Record Updates

• Last Update Posted (Actual): April 10, 2025
• Last Update Submitted That Met QC Criteria: April 8, 2025
• Last Verified: April 1, 2025

More Information

Terms related to this study

• Other Study ID Numbers: IRB23-0131

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No