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

Not Applicable

Active, not recruiting

• Conditions: Implant Complication
• Interventions: Other: Prosthetic-surgical approach + autogenous graft; Other: Prosthetic-surgical approach + graft substitute

• Registration Number: NCT05576922
• Lead Sponsor: Harvard Medical School (HMS and HSDM)

Brief Summary

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

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 Timeline

• Study First Submitted: 2022-10-03
• Study First Submitted QC: 2022-10-08
• Study First Posted: 2022-10-13
• Study Start: 2023-01-04
• Status Verified: 2025-04
• Last Update Submitted: 2025-04-08
• Last Update Posted: 2025-04-10
• Primary Completion: 2025-10-20
• Study Completion: 2025-10-21

Recruitment & Eligibility

• Status: ACTIVE_NOT_RECRUITING
• Sex: All
• Target Recruitment: 28

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 & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Connective tissue graft	Prosthetic-surgical approach + autogenous graft	Autogenous connective tissue graft harvested from the palate as a free gingival graft and then de-epithelialized
Collagen matrix + rhPDGF-BB	Prosthetic-surgical approach + graft substitute	Xenogeneic cross-linked collagen matrix + recombinant human platelet-derived growth factor-BB

Primary Outcome Measures

Name	Time	Method
Soft tissue dehiscence reduction	6 and 12 months	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)

Secondary Outcome Measures

Name	Time	Method
Mucosal thickness changes	3, 6 and 12 months	Changes within the mucosal thickness measured with ultrasonography (expressed in mm)
Post-operative pain	14 days after the surgery	Patient-reported pain after the surgical procedure (expressed with a 0-10 visual analogue scale \[VAS\])
Professional esthetic assessment	12 months	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)
mean peri-implant soft tissue dehiscence (PSTD) coverage	6 and 12 months	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)
Complete peri-implant soft tissue dehiscence (PSTD) coverage	6 and 12 months	Percentage of cases with complete resolution of the implant esthetic complication (expressed as a percentage)
3D Volumetric changes	3, 6 and 12 months	Changes within the buccal contour measured by superimposing digital impressions obtained with optical scanning (expressed in mm\^3)

Trial Locations

Locations (1)

Harvard School of Dental Medicine; 🇺🇸 Boston, Massachusetts, United States