Collagen Matrix + rhPDGF-BB vs Connective Tissue Graft for the Treatment of Peri-implant Soft Tissue Dehiscences

Xenogeneic Collagen Matrix Loaded With rhPDGF-BB vs Autogenous Connective Tissue Graft for the Treatment of Peri-implant Soft Tissue Dehiscences: A Randomized, Controlled, Clinical, Trial

The study aims at comparing two different approaches for the treatment of implant esthetic complications (peri-implant soft tissue dehiscences): autogenous connective tissue graft vs collagen matrix + recombinant human platelet derived growth factor-BB

Study Overview

• Status: Active, not recruiting
• Conditions: Implant Complication
• Intervention / Treatment: Other: Prosthetic-surgical approach + autogenous graft; Other: Prosthetic-surgical approach + graft substitute

Detailed Description

The present randomized clinical trial aims at investigating two approaches (autogenous connective tissue graft vs collagen matrix + recombinant human platelet derived growth factor-BB) when performed in combination with the prosthetic-surgical approach for the treatment of peri-implant soft tissue dehiscences. Clinical, volumetric, ultrasonographic and patient-reported outcomes will be evaluated at different time points up to 1 year.

• Study Type: Interventional
• Enrollment (Actual): 28
• 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: 18 years and older (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 score ≤ 20% (measured at four sites per tooth), iv) Presence of single dental implant in the anterior area (from the first right premolar to the first left premolar) showing a PSTD, with the subjects searching for treatment of this condition,
• Peri-implant papillae not flat (PSTD subclass a or b) (Zucchelli et al., 2019), vi) Implants diagnosed as healthy (Berglundh et al., 2018),
• Ability 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, defined as self-reported daily habit. Occasional smokers won't be excluded,
• History of soft tissue grafting at the implant site showing PSTD within the last 6 months.

Indications for surgical intervention will be established based on patient's esthetic demands and peri-implant soft tissue phenotype.

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; Autogenous connective tissue graft harvested from the palate as a free gingival graft and then de-epithelialized	Other: Prosthetic-surgical approach + autogenous graft; Coronally advanced flap with an autogenous graft (CTG)
Experimental: Collagen matrix + rhPDGF-BB; Xenogeneic cross-linked collagen matrix + recombinant human platelet-derived growth factor-BB	Other: Prosthetic-surgical approach + graft substitute; Coronally advanced flap with a graft substitute (collagen matrix and rhPDGF-BB)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Soft tissue dehiscence reduction	Reduction of the depth of the Soft tissue dehiscence (vertical measurement of the complication, in relation to the level of the cemento-enamel junction of the contralateral homologous tooth) compared to baseline (expressed in millimeters)	6 and 12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Complete peri-implant soft tissue dehiscence (PSTD) coverage	Percentage of cases with complete resolution of the implant esthetic complication (expressed as a percentage)	6 and 12 months
mean peri-implant soft tissue dehiscence (PSTD) coverage	Percentage of coverage of the soft tissue dehiscence compared to baseline, measured with a formula considering final PSTD depth and initial PSTD depth (expressed as a percentage)	6 and 12 months
Mucosal thickness changes	Changes within the mucosal thickness measured with ultrasonography (expressed in mm)	3, 6 and 12 months
3D Volumetric changes	Changes within the buccal contour measured by superimposing digital impressions obtained with optical scanning (expressed in mm^3)	3, 6 and 12 months
Post-operative pain	Patient-reported pain after the surgical procedure (expressed with a 0-10 visual analogue scale [VAS])	14 days after the surgery
Professional esthetic assessment	Esthetic outcomes of the treatment assessed by a calibrated operator using the Implant soft tissue Dehiscence coverage Esthetic Score (IDES) (expressed using points, based on the IDES classification system from Zucchelli et al. 2021)	12 months

Collaborators and Investigators

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

Study record dates

Study Major Dates

• Study Start (Actual): January 4, 2023
• Primary Completion (Estimated): October 20, 2025
• Study Completion (Estimated): October 21, 2025

Study Registration Dates

• First Submitted: October 3, 2022
• First Submitted That Met QC Criteria: October 8, 2022
• First Posted (Actual): October 13, 2022

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: Delta IMPL REC (IRB22-0637)

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