The GUG was obtained from the maxillary premolar area. The dissected graft was fixed to the recipient site using a modified sling suture technique.

The GUG was obtained from the maxillary premolar area, as detailed experimental GUG+MSS group. The dissected graft was fixed to the recipient site using conventional suture technique.

Conventional graft dimensions were determined with aluminum foil and the foil was placed in the palatial region at the level of the maxillary premolars, at least 2 mm away from the free gingival margin of the adjacent teeth. The dissected graft was fixed to the recipient site with 5/0 polypropylene suture using a modified sling suture technique, as detailed experimental GUG+MSS group.

The dissected conventional graft, as detailed experimental CS+MSS group, fixed recipient bed with conventional suture technique, as detailed experimental GUG+CS group.

The GUG was obtained from the maxillary premolar area. A sulcular incision including the marginal gingival tissue, and two vertical incisions, including the distal and mesial papillae, was made in the palatial parts of the premolars. Then, the incision lines were combined and a 1-1.5 mm thick graft of the desired dimensions was dissected. The dissected graft was fixed to the recipient site with 5/0 polypropylene suture using a modified sling suture technique. First, the needle was passed through the graft slightly apical to the mesial papilla on the buccal side and removed from the lingual aspect including lingual papilla. Subsequently, on the distal side, the needle was passed from the lingual side to the buccal side, and it was passed through the graft slightly apical to the distal papilla and removed from the lingual gingiva again. Then it was knotted on the buccal graft by returning to the buccal starting point on the mesial side.

The shrinkage of the graft area was calculated according to the differences between the graft area at baseline, 1st, 3rd months using ImageJ software.

Alginate impressions of each participants were taken from mandibular teeth and an acrylic stent containing both mandibular canine-canine teeth was prepared. The measurements were made relatively with reference to the predetermined points on the stent. KTW was measured as the distance from the buccal midpoint of tooth between the free gingival margin and the alveolar mucosa.

Alginate impressions of each participants were taken from mandibular teeth and an acrylic stent containing both mandibular canine-canine teeth was prepared. The measurements were made relatively with reference to the predetermined points on the stent. The distance between the reference point on the acrylic stent and mucogingival junction was considered as the relative vestibular depth.