Clinical study of flap design to increase the keratinized gingiva around implants: 4-year follow-up.

Since the presence of keratinized gingiva is so important for peri-implant outcome, the aim of this study is to describe a partial thickness flap design to increase the amount of keratinized peri-implant tissue as well as its thickness. A total of 131 implants were placed in 85 patients: 103 implants (78.63%) in the mandible and 28 implants (21.37%) in the maxilla. Before implant placement in edentulous ridge the residual keratinized mucosa usually was measured with a periodontal probe in a buccal-palatal direction. A palatal or lingual incision was made to raise a partial thickness flap with the residual keratinized tissue. After implant placement the flap was apically repositioned and secured with loose periosteal sutures. Keratinized tissue levels were calculated at baseline, at 6 months, and every year follow-up. Measurements were reported for each implant diameter. At 4-year follow-up, implant survival rate of 87.79% was reported. Peri-implant keratinized mucosa confirmed clinical gain in all cases; mean levels at 1- and 4-year follow-ups were 7.26 ± 2.01 mm and 7.37 ± 2.12 mm, respectively. The levels remained stable over time. This flap design allows immediate correction of adaptation of the keratinized tissue around the implant, increasing the thickness and amount of the keratinized tissue.