Description

This prospective randomized controlled trial aims to determine the effectiveness of two different approaches of the "socket seal technique" for the preservation of the soft and hard tissues at the extraction site by utilizing a free gingival graft (FGG) or a PLGA membrane to stabilize the blood clot within the extraction socket compared with spontaneous healing of the tissues.

Primary outcome variable of the study will be alveolar bone changes in height buccally and palatally.

Secondary outcome variables: Alveolar bone changes in width, Mucosa thickness changes, Wound healing visual assessment, Width of keratinized tissues.

Materials and methods Thirty-six subjects will be randomly allocated into one of the three treatment groups based on computer-generated lists using a "block-design". Each patient contributes with one study site.

Study groups:

Group-A: Extraction of the tooth and suturing of the extraction socket with resorbable suture PGA 5/0.

Group-B: Extraction of the tooth, deepithelialization of the gingival colar of the socket, placement of a Free Gingival Graft taken from a standardized location of the palate adjusted to seal the socket opening and then stabilize it by resorbable suture PGA 5/0.

Group-C: Extraction of the tooth, retraction of mucoperiosteal flaps by 2 mm at the opening of the socket using a microsurgical elevator followed by adjustment of the Polylactic-Glycolic Acid membrane over the socket opening resting by 1 mm over the alveolar crest of the extraction socket. Tissues are sutured over the barrier by resorbable suture PGA 5/0.

Timeline of the study/Clinical procedures:

First visit - initial examination - (1 week before the surgery)

• Suitability of subjects
• Consent form; Randomization of the patient
• Radiographic examination (Long-cone paralleling technique using a digital sensor attached to a custom-made silicone bite block for reproducible radiographs)
• Intra-oral photography
• Impression of the examined area in order to create a reference stent to reproduce in a standard manner the clinical/radiographic measurements.
• Full mouth scaling; oral hygiene instructions

Second visit - Baseline - T0

• Clinical measurements with the use of the reference stent of:

(i) The width of keratinized tissues with the use of a periodontal probe (Hu-Friedy XP-23/QW) (ii) The thickness of mucosa with the use of an ultrasonic device SDM (iii) The buccal osseous plate in relation to the gingival margin with a periodontal probe.

• Extraction of the tooth in a standardized way to minimize trauma; Post-surgical instructions will be given to the patient. Treatment of the extraction site accordingly to randomized treatment approach (Group-A, -B, -C).

(i) Radiographic examination: (ii) Standardized intraoral x-ray and standardized CBCT (with the use of a reference stent)

Third visit - T1 - (1 week after the surgery)

• Evidence of healing
• Intra-oral photography

Fourth visit - T2 - (2 weeks after the surgery)

• Evidence of healing
• Removal of sutures
• Intra-oral photography

Fifth visit - T3 - Re-evaluation (6 weeks after the surgery)

• Intra-oral photography
• Width of keratinized tissues with the use of periodontal probe (Hu-Friedy XP-23/QW)
• Thickness of mucosa determined by the ultrasonic device SDM in the aforementioned standardized points with the use of the reference stent.
• Radiographic examination (The long-cone paralleling technique will be used at a distance of 10 cm between the X-ray head and the digital sensor which is attached to a custom-made silicone bite block for reproducible radiographs.)

Sixth visit - T4 - Final evaluation (3 months after the extraction)

• Intra-oral photography
• Record of periodontal plaque index (Pl) and bleeding on probing (BoP) at the adjacent teeth with the use of periodontal probe (Hu-Friedy XP-23/QW).
• Record of the width of keratinized tissues with the use of periodontal probe (Hu-Friedy XP-23/QW) and the thickness with the use of the ultrasonic device SDM in the aforementioned standardized points with the use of the reference stent.
• Radiographic examination with standardized intraoral x-ray and CBCT (with the use of the reference stent)