Soft Tissue Augmentation Around Dental Implants Using Connective Tissue Graft, Submerged Tenting Abutment, or Sub-crestal Implant Placement

NCT07714265 | Recruiting

• 2 other identifiers: PER3253019MIU-IRB-2526-025
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

Peri-implant soft tissue thickness is an important determinant of the long-term stability and success of dental implants. Patients with a thin peri-implant soft tissue phenotype are at increased risk of soft tissue recession, marginal bone loss, and compromised esthetic and functional outcomes. Subepithelial connective tissue graft (SCTG) is considered the gold standard for soft tissue augmentation; however, it requires harvesting tissue from the palate, increasing surgical complexity, operative time, and postoperative morbidity. Less invasive approaches, including submerged tenting abutments and subcrestal implant placement, have been proposed as alternatives to improve peri-implant soft tissue dimensions while reducing patient morbidity, but direct comparative clinical evidence remains limited. This investigator-initiated, single-center, randomized, parallel-group clinical trial will compare three approaches for peri-implant soft tissue augmentation in patients with a thin peri-implant soft tissue phenotype requiring a single dental implant in the posterior mandible. Eligible implant sites will be randomly assigned in a 1:1:1 allocation ratio to receive either subepithelial connective tissue grafting, submerged tenting abutment placement, or subcrestal implant placement during implant surgery. The primary objective is to compare changes in peri-implant soft tissue thickness using three-dimensional digital intraoral scanning over a 12-month follow-up period. Secondary objectives include evaluation of keratinized tissue width, clinical soft tissue thickness, histological characteristics of peri-implant soft tissue, peri-implant crestal bone level changes, postoperative pain, operative time, patient-reported satisfaction, and postoperative complications. The results of this study are expected to provide evidence regarding whether minimally invasive treatment approaches can achieve clinical outcomes comparable to connective tissue grafting while reducing surgical morbidity and improving patient-centered outcomes.

Conditions

Partial Edentulism; Peri-implant Soft Tissue Deficiency; Tooth Loss

Keywords

Dental Implant; Peri-implant Soft Tissue; Soft Tissue Augmentation; Tenting Healing Abutment; Subepithelial Connective Tissue Graft; Digital Volumetric Analysis; Randomized Controlled Trial; Posterior Mandible; Submerged Tenting Abutment; Thin Peri-implant Phenotype; Subcrestal Implant Placement; SCTG; Digital Intraoral Scanner

Outcome Measures

Primary Outcomes (1)

• Change in Peri-implant Soft Tissue Thickness

  Change in peri-implant soft tissue thickness from baseline measured using three-dimensional digital intraoral scanning (Medit Intraoral Scanner) and digital volumetric analysis (Medit Design software). Measurements will be performed by blinded outcome assessors and expressed in millimeters (mm).

  Baseline, 3 months, 6 months, and 12 months after implant placement.

Secondary Outcomes (5)

• Histological Characteristics of Peri-implant Soft Tissue

  3 months

• Clinical Peri-implant Soft Tissue Thickness

  Baseline, 3 months, 6 months, and 12 months

• Postoperative Pain

  Daily during the first 10 postoperative days

• Peri-implant Crestal Bone Level Changes

  Baseline, 3 months, 6 months, and 12 months

• Width of Keratinized Tissue

  Baseline, 3 months, 6 months, and 12 months

Study Arms (3)

Subepithelial Connective Tissue Graft (SCTG)

EXPERIMENTAL

Participants assigned to this arm will receive equi-crestal dental implant placement followed by augmentation of the peri-implant soft tissue using an autogenous subepithelial connective tissue graft harvested from the palate. The graft will be positioned over the implant site to increase peri-implant soft tissue thickness before primary flap closure.

Procedure: subepithelial connective tissue graft

Submerged Tenting Abutment

EXPERIMENTAL

Participants assigned to this arm will receive equicrestal dental implant placement followed by placement of a submerged low-profile tenting healing abutment beneath the flap to support peri-implant soft tissue contour during healing without connective tissue grafting.

Device: Submerged Tenting Abutment

Subcrestal Implant Placement

EXPERIMENTAL

Participants assigned to this arm will receive dental implant placement approximately 2 mm below the alveolar crest without connective tissue grafting or placement of a submerged tenting abutment.

Procedure: Sub-crestal Implant Placement

Interventions

Submerged Tenting Abutment DEVICE

Placement of a submerged low-profile tenting healing abutment over an equicrestally positioned dental implant to support peri-implant soft tissue during healing.

Submerged Tenting Abutment

subepithelial connective tissue graft PROCEDURE

Harvesting of an autogenous connective tissue graft from the palate and placement over an equicrestally positioned dental implant to augment peri-implant soft tissue thickness.

Also known as: SCTG

Subepithelial Connective Tissue Graft (SCTG)

Sub-crestal Implant Placement PROCEDURE

Placement of a dental implant approximately 2 mm apical to the alveolar crest without soft tissue grafting or tenting abutment placement.

Also known as: Subcrestal Implant Placement

Subcrestal Implant Placement

Eligibility Criteria

• Age: 20 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adults aged 20 years or older.
• Partially edentulous patients requiring a single dental implant in the posterior mandible.
• Thin peri-implant soft tissue phenotype (\<2 mm).
• Horizontal alveolar ridge width of at least 6 mm.
• Vertical bone height of at least 10-12 mm, confirmed radiographically.
• Adequate interarch restorative space for implant-supported restoration.
• Medically healthy (American Society of Anesthesiologists \[ASA\] Physical Status I or II).
• Good oral hygiene.
• Able and willing to provide written informed consent.

You may not qualify if:

• Local pathological lesions affecting the surgical site.
• Smoking.
• Pregnancy or breastfeeding.
• Alcohol abuse or parafunctional habits that may compromise implant survival or wound healing.
• Medical or local conditions that could interfere with osseointegration, soft tissue healing, or study participation

Sponsors & Collaborators

• Misr International University: lead

Study Sites (1)

Misr International University Dental Clinic Complex

Cairo, Egypt

RECRUITING

Related Publications (3)

• Lee CT, Tran D, Tsukiboshi Y, Min S, Kim SK, Ayilavarapu S, Weltman R. Clinical efficacy of soft-tissue augmentation on tissue preservation at immediate implant sites: A randomized controlled trial. J Clin Periodontol. 2023 Jul;50(7):1010-1020. doi: 10.1111/jcpe.13816. Epub 2023 Apr 13.

  PMID: 37052357 RESULT

• Thoma DS, Gasser TJW, Hammerle CHF, Strauss FJ, Jung RE. Soft tissue augmentation with a volume-stable collagen matrix or an autogenous connective tissue graft at implant sites: Five-year results of a randomized controlled trial post implant loading. J Periodontol. 2023 Feb;94(2):230-243. doi: 10.1002/JPER.22-0226. Epub 2022 Oct 28.

  PMID: 35904229 RESULT

• 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.

  PMID: 27310522 RESULT

MeSH Terms

Conditions

Tooth Loss

Condition Hierarchy (Ancestors)

Periodontal Diseases; Mouth Diseases; Stomatognathic Diseases; Tooth Diseases

Study Officials

• Hani E elnahass, Phd

  Professor, Department of Oral Medicine and Periodontology, Faculty of Dentistry, Cairo University

  STUDY CHAIR

• Zeinab E Abd El Rahman, Phd

  Lecturer, Department of Oral Medicine, Faculty of Oral and Dental Medicine, Misr International University.

  STUDY DIRECTOR

Central Study Contacts

Baraa M Nagy, BDS

CONTACT

+201063278917; baraa2480582@miuegypt.edu.eg

Zeinab H Abd El Rahman, PhD

CONTACT

zainab.hafez@miuegypt.edu.eg

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Masking Details: Blinding of participants and the operating surgeon is not feasible because of the nature of the surgical interventions. Outcome assessors responsible for clinical, digital, radiographic, and histological measurements will remain blinded to treatment allocation. Statistical analysis will also be performed by a blinded biostatistician.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: This is a single-center, randomized, three-arm, parallel-group clinical trial. Eligible participants requiring a single implant in the posterior mandible and presenting with a thin peri-implant soft tissue phenotype will be randomly assigned in a 1:1:1 allocation ratio to receive one of three interventions: subepithelial connective tissue graft (SCTG), submerged tenting abutment, or sub-crestal implant placement. Participants will remain in their assigned intervention group throughout the study, with follow-up assessments performed over 12 months.

Study Record Dates

• First Submitted: July 15, 2026
• First Posted: July 20, 2026
• Study Start: July 17, 2026
• Primary Completion (Estimated): July 15, 2027
• Study Completion (Estimated): December 15, 2027
• Last Updated: July 21, 2026

Record last verified: 2026-07

Locations

EG (1)