Dimensional Changes in Alveolar Ridge Preservation

Dimensional Changes After Different Alveolar Ridge Preservation Techniques for Posterior Region: Randomized Controlled Trial

Objective: The objective is to evaluate the dimensional changes of soft tissue and alveolar ridge after extraction of posterior elements with different clinical protocols of alveolar preservation.

Detailed methodology: 80 individuals will be selected with need for extraction of premolar and molar elements, from both arches, for non-periodontal reasons, to participate in this randomized controlled clinical study. The dental elements will be extracted atraumatically, and allocated to one of the study groups (n=20/grp): Control Group (Ctl): alveolus closure with total flap elevation and simple suture; Group Free Gingival Mixed Graft (EGLM): closure of the alveolus without flap elevation, and placement of a mixed free gingival tissue graft (epithelialized in the central region and de-epithelialized (2 mm) in the vestibulolingual edges; Bone + Mixed Free Gum Graft Group (B+EGLM): socket closure without flap elevation, placement of lyophilized bone graft and socket sealing with mixed free gingival tissue graft (as previously described); Bone + Titanium Seal Group (B+TS): socket closure without flap elevation, placement of lyophilized bone graft, socket sealing by installing a non-absorbable titanium membrane. Immediately after the extractions, Cone Beam Computed Tomography (90 kVp/8 mA/2.3 sec) will be performed, with lip/cheek separation, with 1.5 mm thick slices and a 1 mm distance, with a field of vision (FOV) of 5±5 cm, which will be repeated after 6 months. During the CT scans, the patients will use intra-oral appliances with hyperdense indicators to determine the reference points to measure the variables: bone tissue height in the center of the socket (primary variable) and every 2 mm equidistantly; thickness of bone tissue in the center of the socket and every 2 mm equidistantly. Soft tissue variables will also be evaluated, such as: mucosal thickness at the height and 2 mm below the edge margin (by CT); height of the keratinized tissue (measured by a dry tip caliper). After 6 months, all patients will receive dental implants, with the ideal measurements for bone dimension, and the possibility of installing implants >10mm or <10mm in length will be statistically analyzed. After 4 months of dental implant placement, single prostheses will be installed and CT, soft tissue measurements and clinical parameters will be repeated (peri-implant depth; presence of biofilm and bleeding on probing; tissue thickness at the margin and 2 mm below; keratinized tissue). Implants will be re-evaluated after 12 months. All measurements will be performed by a previously calibrated examiner (intra-class correlation above 90%). The data will initially be analyzed in a descriptive way, with means and standard deviations. For comparison between groups and times, two-way/Tukey ANOVA test will be used. In all analyses, a significance level of 5% will be considered.

Closure of the alveolus without flap elevation, and placement of a mixed free gingival tissue graft (epithelialized in the central region and de-epithelialized (2 mm) in the vestibulolingual edges

Socket closure without flap elevation, placement of lyophilized bone graft and socket sealing with mixed free gingival tissue graft (as previously described)

Socket closure without flap elevation, placement of lyophilized bone graft, socket sealing by installing a non-absorbable titanium membrane.

Control Group (Ctl): alveolus closure with total flap elevation and simple suture; and socket sealing with mixed free gingival tissue graft.

closure of the alveolus without flap elevation, and placement of a free gingival tissue graft removed from the individual's own palate, which will be properly sutured. This graft is a combination of epithelialized-subepithelial connective tissue graft, which will be taken from the hard palate of the regions.

closure of the socket without flap elevation, placement of a freeze-dried bone graft and sealing of the socket with a mixed free gingival tissue graft.

socket closure without flap elevation, placement of lyophilized bone graft, socket sealing by installing a non-absorbable titanium membrane.

Through CT taken immediately after tooth extraction and six months later, these images will be analyzed to evaluate changes in hard tissues

evaluation of the dimensional change of soft tissues that accompany bone remodeling through linear and volume measurements in the STL

Through STLs taken immediately after extraction and six months later, these images will be analyzed to evaluate changes in soft tissues

Visual analogy scale for pain and disconfort evaluattion which consists of a score to measure the patient's pain intensity.

Inclusion Criteria: Systemic health (Hypertension and Diabetes controlled) Indication of tooth extraction with at least 2/3 of the bone support, in the premolar or molar region Signing the consent form Individuals over 18 years of age. Exclusion Criteria: Presence of periodontal disease at the time of surgery Pregnant and lactating women Smokers Being in orthodontic treatment Use medication that alters the bone healing process, such as those used to treat osteoporosis and the bisphosphonate group Individuals under 18 years of age