The Effect of Free Gingival Graft on Root Closure

Free gingival graft is a mucogingival surgical technique applied to increase keratinized gingival width and reduce gingival recession. Free gingival graft is one of the most widely used approaches in root closure treatments and in increasing the height of the keratinized gingiva. Evaluation of the effect of the amount of creeping attachment on the root surface caused by the free gingival grafts placed coronally and apical to the mucogingival line on the gingival recession in the mandibular anterior region with keratinized gingival deficiency with gingival recession. Forty patients with gingival recession and insufficient keratinized gingival height will be randomly divided into 2 main groups as free gingival grafts to be placed coronal and apical to the gingival recession.

Free gingival graft is a mucogingival surgical technique applied to increase keratinized gingival width and reduce gingival recession. Free gingival graft is one of the most widely used approaches in root closure treatments and in increasing the height of the keratinized gingiva. The "creeping attachment" phenomenon draws attention in the long-term success of root closure treatment in areas with gingival recession. "Creeping attachment" is defined as the coronal movement of the gingiva in the area where free gingival graft or connective tissue is applied in the postoperative period. The mean root closure rate with the creeping attachment is approximately 1 mm and can be detected 1 to 36 days after graft surgery. In the literature, clinical studies that measured a creeping attachment value between 0.12 and 3.5 mm in a 2-year period in free gingival grafts applied to the marginal gingival level have been reported.

Systemically healthy and non-smoking patients older than 18 years of age who applied to Kütahya Health Sciences University, Faculty of Dentistry, Department of Periodontology and had gingival recession in mandibular anterior teeth and keratinized gingival deficiency will be included in the study. Systemic and dental anamnesis will be taken from the patient before the operation and clinical measurements will be recorded.

Patients will be divided into 2 main groups as free gingival grafts to be placed coronal and apical to the gingival recession. They will be written as Group I and Group II in sealed envelopes and apical and coronal positioning groups will be chosen randomly.

The operation date will be given after the patient is given oral hygiene training and 4 weeks after receiving Phase I routine periodontal treatment. The data to be obtained preoperatively and postoperatively are as follows:

Clinical measurements

1. Plaque index (Löe\&Silness): It is obtained by measuring with a periodontal probe from 4 regions of a tooth (mesial, distal, buccal and lingual).
2. Gingival index (Silness\&Löe): It is obtained by measuring with a periodontal probe from 4 regions of a tooth (mesial, distal, buccal and lingual).
3. Attachment loss: It is the value of the distance between a tooth and the free gingiva based on the enamel-cementum boundary measured using a periodontal sonde.
4. Bleeding index on probing (Ainamo \& Bay): In this index, probing is performed by gently walking around the pocket. As a result of probing, the evaluation is made by looking at the presence or absence of bleeding in the gingiva. A positive value is given if bleeding occurs within 10-15 seconds after probing in the mesial, distal, buccal and lingual gingival parts of all teeth. The ratio of the bleeding area to the examined area is expressed as %.
5. Pocket depth: It is the vertical distance measured between a standard periodontal probe and the base of the periodontal sulcus and the gingival margin.
6. Keratinized gingival height: It is the distance from the free gingival margin to the mucogingival junction line.
7. Keratinized gingival thickness: It is the distance measured between the gingival surface and hard tissue with a standard periodontal probe inserted perpendicular to the keratinized gingiva.
8. Gingival recession depth: It is obtained by measuring the distance between the gingival margin in the midbuccal region and the enamel-cementum boundary.
9. Gingival recession width: It is the mesio-distal width of the recession from the midpoint of the distance between the enamel cementum border and the gingival margin.
10. Gingival phenotype: Visibility of the periodontal tube in the sulcus
11. Vestibular sulcus depth: It is the distance measured from the gingival margin to the base of the sulcus.

Sample Selection: Taking the effect size of 0.08 for the significance value in the G Power analysis program as a reference to a previously presented study, 40 teeth were planned to be taken for α= 0.05 and 80% power.

Statistical Analysis method:

All analyzes will be done with SPSS software. Intra-group temporal evaluations in test and control groups will be evaluated using Pairedsample -T or Wilcoxon test according to normal distribution values. For intergroup comparisons, according to the normal distribution of data, Student-t test will be analyzed in parametric within-group evaluations and Mann Withney U test in nonparametrics. The normal distribution of the data will be evaluated with the Kolmogorov-Smirnov test. The significance value will be taken as 0.05. Relationships between variables will be evaluated with Logistic Regression Analysis or Multivariate Regression Analysis.

Eligibility Criteria:
Inclusion Criteria:

1. 18-99 years old
2. The patient does not have any systemic disease
3. Presence of at least one tooth with gingival recession in the mandibular anterior region
4. Excessive dentin sensitivity and impaired esthetics associated with recession
5. Identification of the enamel-cementum boundary in the shrinkage region
6. The tooth is alive and there are no irregularities, grooves, caries and restorations in the area to be treated.
7. No periodontal surgical treatment in the relevant areas in the last 24 months
8. Presence of adequate keratinized and attached gingiva in the donor area

Exclusion Criteria:

1. Being outside the specified age range
2. Any contraindication for systematic periodontal surgery
3. Failure to define the enamel-cementum boundary in the withdrawal region
4. Presence of caries, restoration, root concavity in the area to be treated
5. Patients who smoke more than 10 cigarettes per day
6. Patients who use drugs that suppress the immune system or impair recovery
7. Patients using drugs that impair bleeding
8. Insufficient keratinized and attached gingiva in the donor area