A Randomized Control Trial Testing Connective Tissue Grafts vs. Allograft on Dental Implants

University of Michigan

Status: Completed

Conditions: Dental Implant Soft Tissue Defects in the Anterior Maxilla

Treatments: Procedure: Soft Tissue Grafting

Study type: Interventional

Funder types: Other; Industry

Identifiers

NCT01934530

UM-Anderson-10

Details and patient eligibility

About

This randomized controlled clinical pilot trial compared the efficacy of two soft tissue grafting methods for correcting esthetic discrepancies associated with non-molar implants in the maxilla. Specifically, it was explored whether defects treated with connective tissue grafts (SCTG) differed in their outcomes from defects treated with acellular dermal matrix allografts (ADM).

Full description

Thirteen patients who presented with implants displaying recession, thin biotype, concavity defects or a combination thereof associated with single crowned dental implants participated in this randomized control trial. The control group (N=7) received SCTG and the test group (N=6) received ADM, both under coronally positioned flaps. Data were collected before surgery, and 6 weeks, 3 months, and 6 months after the surgery. Outcome measures included soft tissue, hard tissue, and esthetics parameters and psychosocial data.

Enrollment: 13 patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Healthy adults of at least 18 years of age
• Maxillary non-molar implant with failing pink esthetic profile
• Implants with adjacent landmarks (only one can be an implant)
• Healthy implants measured by the lack of peri-implantitis and mucositis
• Good oral hygiene.

Exclusion criteria

• Unstable systemic diseases, compromised immune system, or unstable bleeding disorders
• History of radiation or cancer in the oral cavity
• Use of IV bisphosphonate or steroid medication
• Use of tobacco products (>1/2 pack per day)
• Pregnancy
• Mucogingival surgery or implant placement within the past six months

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

---

13 participants in 2 patient groups

Connective Tissue Graft - Control

Active Comparator group

Description:

The donor tissue was harvested from tissue palatal to maxillary premolars and anterior to the mesial of the first molars. A horizontal incision corresponding to the width of the recipient bed plus 4mm was made 3 mm apical to the gingival margin. A small secondary vertical incision was tolerated on the mesial aspect of the surgical site to allow for a split thickness technique. The flap was then positioned over the graft and sutured with attempts to cover the grafted tissue to 2mm coronal to the implant/abutment interface pending flap tension. Follow up was monitored over 6 months at various time-points.

Treatment:

Procedure: Soft Tissue Grafting

Alloderm - Test

Experimental group

Description:

ADM graft was prepared according to the manufacturer's instructions. The preparation requires rehydration in 50ml sterile saline or Ringers Solution for five minutes and repeated twice. The graft was then transferred to the recipient bed with the basement membrane side facing up and connective tissue on the periosteum. The allograft was trimmed to cover the defect dimensions up to the implant-abutment interface. There was a 4mm margin added to the width on each side to account for lateral contraction as with the connective tissue. With sterile moist gauze, pressure was applied to the graft for proper adaptation to the wound bed. The graft was sutured with a single sling and the flap with a double sling. Simple interrupted sutures were used to close vertical releases.

Treatment:

Procedure: Soft Tissue Grafting