The clinical effect of acellular dermal matrix on gingival thickness and root coverage compared to coronally positioned flap alone

Background: The primary aim of this randomized, controlled, blinded, clinical investigation was to compare the coronally positioned flap (CPF) plus an acellular dermal matrix (ADM) allograft to CPF alone to determine their effect on gingival thickness and percent root coverage. Methods: Twenty-four subjects with one Miller Class I or II buccal recession defect of 3 mm were treated with a CPF plus ADM or a CPF alone. Multiple additional recession sites were treated with the same flap procedure, and all sites were studied for 6 months. Tissue thickness was measured at the sulcus base and at the mucogingival junction of all teeth, with an SDM ultrasonic gingival thickness meter. Results: For the ADM sites, mean initial recession of 3.46 m mm was reduced to 0.04 mm for defect coverage of 3.42 mm or 99% (P <0.05). For the CPF group, mean initial recession of 3.27 mm was reduced to 1.08 mm for defect coverage of 2.19 mm or 67% (P <0.05). The difference between ADM and CPF groups was statistically significant (P <0.05). Marginal soft-tissue thickness was increased by 0.40 mm (P <0.05) for the ADM group, whereas the CPF group remained essentially unchanged. Keratinized tissue was increased for the ADM group by 0.81 mm (P <0.05), whereas the CPF group increased by 0.33 mm (P >0.05). No additional root coverage was gained due to creeping attachment between 2 and 6 months for either group. Conclusions: Treatment with a CPF plus an ADM allograft significantly increased gingival thickness when compared with a CPF alone. Recession defect coverage was significantly improved with the use of ADM.