Effect of Collagen Membrane on Ridge Preservation

Effect of Collagen Membrane on Ridge Preservation for Delayed Implant Placement in Sites With Absent Buccal Bone Wall: A Randomized Controlled Trial

This study will evaluate whether adding a resorbable collagen membrane to an anorganic bone-collagen composite (ABCC) graft improves ridge preservation after tooth extraction. Ridge preservation is a procedure used to maintain the shape and volume of the jawbone following tooth removal, which is important for future dental implant placement.

Participants will be randomly assigned to receive either ABCC alone or ABCC combined with a collagen membrane. Healing outcomes will be assessed after approximately 4 months using three-dimensional cone beam computed tomography (CBCT) scans.

The primary outcome is the change in horizontal ridge dimension (width). Secondary outcomes include vertical and contour changes in ridge dimensions, changes in soft tissue contour assessed with digital scans, postoperative healing and complications (such as wound dehiscence, swelling, or infection), and patient-reported outcomes, including pain and satisfaction. In a subset of participants, bone healing will also be evaluated using laboratory and imaging analyses of bone samples obtained at the time of implant placement. The study will additionally assess whether the treatment allows implant placement in the ideal position without the need for further bone grafting.

Study Overview

• Status: Not yet recruiting
• Conditions: Alveolar Bone Loss; Tooth Extraction; Dehiscence
• Intervention / Treatment: Procedure: Minimally Invasive tooth extraction; Device: Alveolar ridge preservation with ABCC; Device: Resorbable collagen membrane (InterCollagen® Guide)

Detailed Description

This study is a clinical trial that evaluates two different approaches to preserve the jawbone after tooth extraction in areas where part of the bone is already missing. Preserving the bone is important to support future dental implants.

Participants will be randomly assigned (like flipping a coin) to receive one of two treatments: a bone graft material alone, or the same bone graft combined with a protective collagen membrane placed over it.

Tooth extraction and follow-up care will be performed in the same manner for all participants. After approximately 4 months of healing, participants will return for dental implant placement.

During the healing period and at the time of implant placement, the research team will evaluate how well the bone and gums have healed. This will include three-dimensional CBCT scans, digital intraoral scans, and clinical measurements. In some participants, a small sample of bone will be collected at the time of implant placement to study bone healing.

The study will compare how effectively each treatment maintains the shape and volume of the jawbone, the quality of soft tissue healing, the risk of complications, patient-reported outcomes (PROs), including comfort and satisfaction, and whether additional procedures are required prior to implant placement.

• Study Type: Interventional
• Enrollment (Estimated): 30
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Carla Sanchez, MS; Phone Number: 4126241179; Email: cab28@pitt.edu
• Study Contact Backup: Name: Debora R Dias, DDS, PhD; Phone Number: 4126488595; Email: deboradias@pitt.edu

Study Locations

• United States
  • Pennsylvania
    • Pittsburgh, Pennsylvania, United States, 15213
      • University of Pittsburgh School of Dental Medicine, Department of Periodontics and Preventive Dentistry
      • Contact: Debora R Dias, DDS, PhD; Phone Number: 4126488595; Email: deboradias@pitt.edu
      • Contact: Andrea Ravida, DDS, PhD; Phone Number: 7347309678; Email: andrearavida@pitt.edu
      • Principal Investigator: Debora R Dias, DDS, PhD

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Adults aged 18-80
• Indicated for extraction of a single-rooted maxillary tooth
• ≥ 50% buccal bone dehiscence confirmed by CBCT reconstructions
• Presence of both adjacent teeth
• No interproximal bone loss
• ASA I-II health status
• Ability to comply with required procedures, including attending required number of clinic visits

Exclusion Criteria:

• Patients diagnosed with periodontitis adjacent to the area to be treated
• History of allergic reactions to local anesthetics or bone graft material (self-reported);
• Current heavy smokers (≥ 10 cigarettes/day) or those who quit smoking recently (self-reported; last 6 months);
• Diagnosis of diabetes mellitus, liver or kidney failure (self-reported);
• Presence of active infectious diseases of any kind;
• History of chemotherapy or radiation therapy to the head or neck within the past 5 years (self-reported);
• Severe hematologic disorders (risk for hemorrhage)(self-reported);
• Assumption of corticosteroids, IV bisphosphonates or immunosuppressive drugs;
• Any history of alcohol or drug abuse (self-reported);
• Pregnancy or plans to become pregnant within 4 months of study enrollment (self-reported);

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: Control group (bone graft only); Control group (bone graft only): The socket will be grafted with ABCC alone. The socket entrance will be covered with a collagen sponge, which will be secured with passive cross-mattress polytetrafluoroethylene sutures (PTFE) without attempting primary closure.	Procedure: Minimally Invasive tooth extraction; Tooth extraction will be performed by a calibrated periodontist using a minimally invasive, flapless, atraumatic technique with periotomes and elevators to preserve socket architecture. Granulation tissue will be carefully removed without flap elevation.; Device: Alveolar ridge preservation with ABCC; The extraction socket will be grafted with ABCC (SigmaGraft®).
Experimental: Test group (bone graft + collagen membrane); Test group (bone graft + collagen membrane): A buccal pouch will be created on the buccal aspect, between the bone and the buccal flap, using tunneling instruments to accommodate the resorbable collagen membrane (InterCollagen® Guide, SigmaGraft). The socket will then be grafted with ABCC. The socket entrance will be covered with a collagen sponge, which will be secured with passive cross-mattress PTFE sutures without attempting primary closure.	Procedure: Minimally Invasive tooth extraction; Tooth extraction will be performed by a calibrated periodontist using a minimally invasive, flapless, atraumatic technique with periotomes and elevators to preserve socket architecture. Granulation tissue will be carefully removed without flap elevation.; Device: Alveolar ridge preservation with ABCC; The extraction socket will be grafted with ABCC (SigmaGraft®).; Device: Resorbable collagen membrane (InterCollagen® Guide); A buccal pouch will be created on the buccal aspect, between the bone and the buccal flap, using tunneling instruments to accommodate a resorbable collagen membrane (InterCollagen® Guide; SigmaGraft®). The membrane will be positioned in the buccal tunnel to replace the missing buccal bone wall and provide graft containment.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Horizontal dimensional changes (%)	Change in horizontal ridge width at 3 mm apical to the crest, measured on CBCT scans and expressed in percentage change.	Baseline and 4 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Horizontal dimensional changes (%)	Change in horizontal ridge width at 1 mm apical to the crest, measured on CBCT scans and expressed in percentage change.	Baseline and 4 months
Horizontal dimensional changes (%)	Change in horizontal ridge width at 5 mm apical to the crest, measured on CBCT scans and expressed in percentage change.	Baseline and 4 months
Vertical dimensional changes (%)	Change in vertical ridge height at the midbuccal aspect, measured on CBCT scans and expressed in percentage change.	Baseline and 4 months
Vertical dimensional changes (%)	Change in vertical ridge height at the mid palatal aspect, measured on CBCT scans and expressed in percentage change.	Baseline and 4 months
Volumetric dimensional changes (%)	Change in the volume of the alveolar process (mm3), measured on CBCT scans in comparison to baseline and expressed in percentage change.	Baseline and 4 months
Mid-buccal soft tissue contour change (mm)	Linear measurement (mm) of mid-buccal soft tissue profile change assessed by superimposition of stereolithography (STL) datasets. Adjacent teeth are used as reference for alignment. A positive value indicates soft tissue gain; a negative value indicates recession.	Baseline and 4 months
Mid-buccal soft tissue volume change (%)	Volumetric change (mm³) in mid-buccal soft tissue contour calculated by superimposition of STL datasets and expressed in percentage. Color-coded deviation maps will illustrate areas of soft tissue collapse or gain.	Baseline and 4 months
Interproximal papilla height change (mm)	Linear measurement (mm) of interproximal papilla height change assessed by superimposition of STL datasets in comparison to baseline. A positive value indicates papilla gain; a negative value indicates papilla loss.	Baseline and 4 months
Wound healing (Wound Healing Index)	Wound healing quality assessed using the Wound Healing Index (WHI), a 3-point ordinal scale where 1 = uneventful healing (complete soft tissue coverage, no complications), 2 = normal healing with minor complications, and 3 = poor healing (dehiscence, exposure, or infection requiring intervention). Lower scores indicate better healing.	1 week, 2 weeks, 1 month, 4 months
Incidence of postoperative complications (Percentage)	Proportion of participants experiencing at least one postoperative complication (edema, erythema, suppuration, graft exposure, or wound dehiscence) at any follow-up visit. Complications will be recorded by a blinded clinical examiner at each scheduled visit.	1 week, 2 weeks, 1 month, 4 months
Postoperative pain	Numeric scale (0-10) for pain after the extraction and ridge preservation procedure.	Day 1, Day 3, 1 week
Oral health-related quality of life (OHIP-14)	Oral health-related quality of life assessed using the Oral Health Impact Profile - 14 (OHIP-14), a validated 14-item questionnaire.	Baseline, 2 weeks, 4 months
Feasibility of prosthetically ideal implant placement without additional augmentation	Ability to place the implant in a prosthetically ideal three-dimensional position at reentry without the need for additional hard-tissue augmentation.	4 months
Histological Outcomes	In a subset of patients, a bone core biopsy will be obtained. Percent area of new bone, residual graft, and marrow spaces assessed by histomorphometric analysis of bone core biopsies obtained at the time of implant placement.	4 months
Patient satisfaction (VAS)	Visual analogue scale (0-100) of patient satisfaction with the appearance of the soft tissues	4 months

Collaborators and Investigators

• Sponsor: Debora Dias
• Collaborators: SigmaGraft Inc.
• Investigators: Principal Investigator: Debora R Dias, DDS, PhD, University of Pittsburgh, Department of Periodontics and Preventive Dentistry

Publications and helpful links

General Publications

• Thoma DS, Zeltner M, Hilbe M, Hammerle CH, Husler J, Jung RE. Randomized controlled clinical study evaluating effectiveness and safety of a volume-stable collagen matrix compared to autogenous connective tissue grafts for soft tissue augmentation at implant sites. J Clin Periodontol. 2016 Oct;43(10):874-85. doi: 10.1111/jcpe.12588. Epub 2016 Aug 12.
• Araujo MG, Lindhe J. Dimensional ridge alterations following tooth extraction. An experimental study in the dog. J Clin Periodontol. 2005 Feb;32(2):212-8. doi: 10.1111/j.1600-051X.2005.00642.x.
• Hutton CG, Johnson GK, Barwacz CA, Allareddy V, Avila-Ortiz G. Comparison of two different surgical approaches to increase peri-implant mucosal thickness: A randomized controlled clinical trial. J Periodontol. 2018 Jul;89(7):807-814. doi: 10.1002/JPER.17-0597. Epub 2018 Jul 20.
• Natto ZS, Parashis A, Steffensen B, Ganguly R, Finkelman MD, Jeong YN. Efficacy of collagen matrix seal and collagen sponge on ridge preservation in combination with bone allograft: A randomized controlled clinical trial. J Clin Periodontol. 2017 Jun;44(6):649-659. doi: 10.1111/jcpe.12722. Epub 2017 May 26.
• Tonetti MS, Sanz M, Avila-Ortiz G, Berglundh T, Cairo F, Derks J, Figuero E, Graziani F, Guerra F, Heitz-Mayfield L, Jung RE, Lai H, Needleman I, Papapanou PN, Sailer I, Sanz-Sanchez I, Schwarz F, Shi J, Thoma D. Relevant domains, core outcome sets and measurements for implant dentistry clinical trials: The Implant Dentistry Core Outcome Set and Measurement (ID-COSM) international consensus report. J Clin Periodontol. 2023 May;50 Suppl 25:5-21. doi: 10.1111/jcpe.13808. Epub 2023 May 4.
• Vignoletti F, Matesanz P, Rodrigo D, Figuero E, Martin C, Sanz M. Surgical protocols for ridge preservation after tooth extraction. A systematic review. Clin Oral Implants Res. 2012 Feb;23 Suppl 5:22-38. doi: 10.1111/j.1600-0501.2011.02331.x.
• Barone A, Toti P, Quaranta A, Alfonsi F, Cucchi A, Calvo-Guirado JL, Negri B, Di Felice R, Covani U. Volumetric analysis of remodelling pattern after ridge preservation comparing use of two types of xenografts. A multicentre randomized clinical trial. Clin Oral Implants Res. 2016 Nov;27(11):e105-e115. doi: 10.1111/clr.12572. Epub 2015 Feb 26.
• Avila-Ortiz G, Couso-Queiruga E, Stuhr S, Chambrone L. Long-term outcomes of post-extraction alveolar ridge preservation and alveolar ridge reconstruction followed by delayed implant placement: A systematic review. Periodontol 2000. 2025 Jul 3. doi: 10.1111/prd.12642. Online ahead of print.
• Araujo MG, Dias DR, Matarazzo F. Anatomical characteristics of the alveolar process and basal bone that have an effect on socket healing. Periodontol 2000. 2023 Oct;93(1):277-288. doi: 10.1111/prd.12506. Epub 2023 Aug 2.

Study record dates

Study Major Dates

• Study Start (Estimated): May 10, 2026
• Primary Completion (Estimated): October 31, 2027
• Study Completion (Estimated): October 31, 2027

Study Registration Dates

• First Submitted: April 10, 2026
• First Submitted That Met QC Criteria: May 6, 2026
• First Posted (Actual): May 12, 2026

Study Record Updates

• Last Update Posted (Actual): May 12, 2026
• Last Update Submitted That Met QC Criteria: May 6, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Collagen membrane; Socket grafting; Ridge preservation; Delayed implant placement; Buccal bone loss
• Additional Relevant MeSH Terms: Bone Resorption; Bone Diseases; Musculoskeletal Diseases; Periodontal Atrophy; Periodontal Diseases; Mouth Diseases; Stomatognathic Diseases; Alveolar Bone Loss
• Other Study ID Numbers: STUDY25080006

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared outside the primary research group due to concerns regarding participant privacy and confidentiality, as approved by the University of Pittsburgh Institutional Review Board.

Drug and device information, study documents

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