Augmentation of the hard palate thin masticatory mucosa in the potential connective tissue donor sites using two collagen materials-Clinical and histological comparison

Background: Due to the similarity of keratinized gingival and palatal mucosa the latter can pose as a potential donor site for gingival recession coverage. However, its availability is restricted and a thin transplant bears the risk of being rejected. The aim of the present study was to compare the clinical and histological results of thin palatal mucosa augmentation, using lyophilized Biokol (R) xenogenous collagen sponge and a suspension of xenogenous Gel 0 (R) pure collagen with non-augmented tissue from the same patients. Materials and methods: Ten patients simultaneously underwent bilateral augmentation procedures using Biokol (R) and Gel 0 (R) collagen material. The donor sites were augmented 8 weeks prior to the harvesting of the connective tissue graft (CTG) for the gingival recession coverage procedures. Prior to the implantation of the collagen material and during the course of harvesting the augmented CTG, tissue specimens were taken for histological examination. Prior to the commencement of the study and after it, the parameters of palatal gingival thickness at 4 mm (PGT1), and at 8 mm apical to the gingival margin (PGT2) around the teeth neighboring the operating fields were determined. Results: In both groups the palatal mucosa had thickened significantly in both measuring sites. An inter-roup comparison revealed greater thickening of the masticatory mucosa in the Biokol (R) group at both measuring points. The histological image of the grafts, obtained from sites augmented using both test methods, revealed a typical pattern of mature fibrous connective tissue. No epithelial cells were found. Conclusion: Augmentation of thin masticatory mucosa using Biokol (R) or Gel 0 (R) collagen materials resulted in a significant thickening of the mucosa, which could be demonstrated to be greater in the first group. (C) 2016 Elsevier GmbH. All rights reserved.