CTG Versus Collagen Matrix for Peri-Implant Soft Tissue Augmentation

Results of Soft Tissue Grafting Around Implant in the Mandible Molar Area

This randomized controlled trial compares two techniques for peri-implant soft tissue augmentation in the mandibular molar region: an autogenous connective tissue graft (CTG) and a collagen matrix. Adult patients requiring implant treatment with insufficient peri-implant soft tissue thickness will be randomly assigned to receive either CTG or a collagen matrix at the time of implant surgery.

The study aims to evaluate and compare changes in peri-implant soft tissue thickness, width of keratinized tissue, and soft tissue contour over a 9-month follow-up period, as well as the occurrence of postoperative complications. The results of this study will help determine whether a collagen matrix can provide clinical outcomes comparable to those of connective tissue grafting for peri-implant soft tissue augmentation.

Study Overview

• Status: Not yet recruiting
• Conditions: Peri-implant Soft Tissue Deficiency; Insufficient Peri-implant Keratinized Tissue
• Intervention / Treatment: Procedure: Connective Tissue Graft; Device: Collagen Matrix

Detailed Description

This randomized controlled trial is designed to compare two approaches for peri-implant soft tissue augmentation in the mandibular molar region: an autogenous connective tissue graft (CTG) and a collagen matrix. Adult patients with insufficient peri-implant soft tissue thickness will be enrolled and randomly allocated in a 1:1 ratio to receive either CTG or a collagen matrix at the time of implant surgery. Randomization will be performed using a block randomization method, and outcome assessment will be conducted by a blinded examiner.

Clinical and digital evaluations will be performed at predefined time points, including baseline and follow-up visits up to 9 months after surgery. Peri-implant soft tissue thickness, width of keratinized tissue, and soft tissue contour changes will be assessed using standardized clinical measurements and digital workflows based on intraoral scanning and cone-beam computed tomography where indicated. Postoperative healing and adverse events will be monitored throughout the follow-up period.

The study is conducted at a single academic center and is intended to provide comparative clinical data on the effectiveness and safety of collagen matrix versus connective tissue grafting for peri-implant soft tissue augmentation.

• Study Type: Interventional
• Enrollment (Estimated): 46
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Phu Manh Nguyen, DDS, MSc; Email: manhphu@hmu.edu.vn

Study Locations

• Vietnam
  • Hanoi, Vietnam
    • Hanoi Medical University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

Adults aged 18 to 65 years.

Patients requiring dental implant treatment in the mandibular molar region.

Presence of insufficient peri-implant soft tissue thickness (< 2 mm).

Adequate general health to undergo minor oral surgery.

Ability and willingness to provide written informed consent and comply with study procedures.

Exclusion Criteria:

Systemic conditions or medications that may impair wound healing.

Heavy smoking (more than 10 cigarettes per day).

History of allergy or hypersensitivity to collagen-based materials.

Previous graft failure or complications at the intended implant site.

Loss of three or more adjacent teeth in the study area (excluding third molars).

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Connective Tissue Graft (CTG); Peri-implant soft tissue augmentation using autogenous connective tissue graft.	Procedure: Connective Tissue Graft; An autogenous connective tissue graft harvested from the patient is used for peri-implant soft tissue augmentation at the time of implant surgery.
Experimental: Collagen Matrix; Peri-implant soft tissue augmentation using a collagen matrix.	Device: Collagen Matrix; A porcine-derived collagen matrix is used for peri-implant soft tissue augmentation at the time of implant surgery, serving as a substitute for autogenous connective tissue grafting.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in peri-implant soft tissue thickness	Change in peri-implant soft tissue thickness measured using standardized digital methods.	Baseline (before surgery) to 9 months after surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in width of peri-implant keratinized tissue	Change in the width of keratinized tissue around the implant measured clinically using standardized procedures.	Baseline to 9 months after surgery
Change in peri-implant marginal bone level	Changes in marginal bone level assessed using cone-beam computed tomography where indicated.	Baseline to 9 months after surgery
Peri-implant clinical indices	Assessment of peri-implant inflammation using standardized clinical indices.	Up to 9 months after surgery

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postoperative complications and adverse events	Incidence of postoperative complications, including soft tissue necrosis, infection, bleeding, implant failure, and other adverse events.	Up to 9 months after surgery

Collaborators and Investigators

• Sponsor: Hanoi Medical University

Study record dates

Study Major Dates

• Study Start (Estimated): February 1, 2026
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): December 1, 2028

Study Registration Dates

• First Submitted: January 19, 2026
• First Submitted That Met QC Criteria: January 19, 2026
• First Posted (Actual): January 28, 2026

Study Record Updates

• Last Update Posted (Actual): January 29, 2026
• Last Update Submitted That Met QC Criteria: January 27, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: Dental implant; Connective tissue graft; Collagen matrix; Peri-implant soft tissue augmentation
• Other Study ID Numbers: 01250159

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared because the dataset contains sensitive clinical and imaging information, and data sharing was not included in the approved study protocol or informed consent.

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