This study aims to compare the changes in the peri-implant mucosa during the application of two soft tissue grafting methods, which are free gingival graft (FGG) and connective tissue graft (CTG) taken from the palatine in terms of the width of the keratinized mucosa and the thickness of the peri-implant soft tissues.

The presence of adequate width of the keratinized gingiva may be necessary in some special cases such as the presence of fixed prostheses on the teeth with sublingual margins or peri implants. There is an association between insufficiency of the keratinized tissues peri implants with greater plaque accumulation, signs of inflammation, soft tissue recession, and loss of attachment. The sample will consist of 33 dental implant sites and divide randomly into three groups: Group I (Experiential, n=11): FGG; Group II: (Experiential, n=11): CTG; and Group III: (Control, n=11): No procedure will be done to improve the quality of the peri-implant tissues. The width of the keratinized gingiva will be measured preoperative with a UNC-15 and the thickness of the peri-implant soft tissues will be measured clinically by direct transgingival propping method. These measurements will be repeated after 1 and 3 months.

Inclusion Criteria:

1. patients who have lost posterior teeth (premolars or molars).
2. A decrease in the amount of keratinized gingiva (less than 2 mm from the alveolar process to the mucogingival junction).
3. good oral health (plaque index ≤1).

Exclusion Criteria:

1. heavy smokers (more than 10 cigarettes per day)
2. uncontrolled diabetes or other systemic diseases.