Comparative Analysis Using the Collagen Matrix and Autogenous Graft: Clinical Course, Aesthetic Results

This was an interventional prospective randomized clinical trial (RCT) in parallel groups. The sample size is 32 patients who were randomly divided into two groups depending on the surgical intervention used. First group - patients underwent increasing the thickness of the mucous membrane using free connective tissue graft from tuberosity area of the upper jaw. Second group - patients used collagen matrix Fibro-Gide" (Geistlich Pharma AG, Bahnhofstrasse 40, 6110 Wolhusen, Switzerland; registration in Russia 19.08.2020 No FSZ -20207/11765). In the postoperative period the value of soft tissue thickness gain, severity of pain, collateral edema, amount of analgesics consumed, soft tissue aesthetics, keratinized mucosa width, quality of life and duration of surgery were assessed.

The aim of this research was to perform a comparative clinical analysis of soft tissues in the area of soft tissue graft and collagen matrix transplantation. Thirty two patients diagnosed with partial absence of teeth was examined on the basis of the Department of Surgical Dentistry of the E.V. Borovsky Institute of Dentistry of I.M. Sechenov First Moscow State Medical University. Patients had a soft tissue thickness deficiency from the vestibular surface in the area of the planned dental implant placement in the distal parts of the mandible, which was an indication for its increase. All patients were randomly divided into two groups depending on method of soft tissue augmentation used. In 1 group (n=16) transplantation of a free connective tissue graft (CTG) from tuberosity area of the upper jaw was performed. In 2 group (n=16) collagen matrix "Fibro-Gide" was used. According to gender and age characteristics, both groups were comparable. Randomization of patients was carried out at the stage of surgical intervention as follows: after a dental implant placement and preparation of recipient's bed, an envelope with a randomly assigned treatment method (using a connective tissue graft or a collagen matrix) was opened.

During the operation, incision was made along the top of the alveolar ridge within the defect; a full-thickness muco-periosteal flap was elevated. Traditional 2-stage dental implantation was performed according to surgical protocols of dental implant systems Astra Tech (Dentsply Implants Manufacturing GmbH, Germany; registration in Russia 27.12.2019 No FSZ 2015/3214). A free connective tissue graft was harvested in patients of the first group. Graft was fixed with a horizontal U-shaped suture to the buccal muco-periosteal flap. In second patients group a fragment of the collagen matrix "Fibro-Gide" was fixed to the buccal muco-periosteal flap (Geistlich Pharma AG, Bahnhofstrasse 40, 6110 Wolhusen, Switzerland; registration in Russia 19.08.2020 No FSZ - 20207/11765). For patients of all groups mobilization of the muco-periosteal flap conducted followed by suturing the wound tightly without tension with simple interrupted sutures.

Postoperative recommendations included standard antibacterial and anti-inflammatory therapy in combination with the use of local antiseptics for daily care was prescribed.

Eligibility Criteria:
Inclusion Criteria:

1. The presence of written informed consent of the patient to participate in the study;
2. Age from 25 to 59 years;
3. The presence of an included defect in the distal part of the lower jaw with a sufficient volume of bone tissue;
4. Soft tissue thickness \<3 mm on the vestibular side;
5. Adjacent teeth without periodontal pathology, the depth of probing should not exceed 3 mm along the entire dentoalveolar furrow;
6. Satisfactory level of oral hygiene;
7. Patients without concomitant pathology or with concomitant pathology in the compensation stage.

Non-inclusion criteria:

1. Age less than 25 and more than 59 years;
2. Hard smokers (more than 10 cigarettes a day);
3. The presence of concomitant pathology in the stage of decompensation;
4. Patients with malignant tumors, as well as patients with a history of radiation and chemotherapy over the past 5 years;
5. Taking medications that affect the healing of soft tissues (nonsteroidal anti-inflammatory drugs, steroid drugs);
6. Pregnancy and breastfeeding;
7. Patients with mental disorders.

Exclusion Criteria:

1. Patients with infections either periodontally or periapically, which developed after inclusion in the study;
2. Pregnancy following entrance into the study;
3. Patients having poor oral hygiene or not wanting to carry out oral hygiene measures;
4. Patients who, for one reason or another, could not complete the entire protocol to the end.