[Efficacy of tunnel technique for treatment of gingival recession of upper adjacent teeth with noncarious cervical defect].

OBJECTIVE: To evaluate the efficacy of tunnel technique (TUN) in treatment of teeth with adjacent gingival regression (GR) combined with noncarious cervical lesions (NCCL). METHODS: We collected data from 21 patients (79 teeth) undergoing TUN surgery for GR combined with NCCL. According to GR depth (GRD) and lesion depth (LD) of NCCL, the teeth were divided into group 1 with GRD</=3 mm and LD</=1 mm; group 2 with GRD</=3 mm and LD>1mm; group 3 with GRD>3 mm and LD</=1 mm; and group 4 with GRD>3 mm and LD>1 mm. The mean root coverage (MRC) rate, complete root coverage (CRC) rate, keratinized gingival width, and keratinized gingival thickness were compared among the 4 groups after TUN surgery. RESULTS: The keratinized gingival width and thickness were significantly improved after the surgery in the 4 groups. When the GRD was below 3 mm, the MRC was not significantly different between group 1 and group 2 (8.55% vs 95.45%, P>0.05); When the GRD was beyond 3 mm, the MRC and CRC rates were both decreased in group 3 and group 4, especially in group 4, where the CRC rate (25%) was significantly lower than those in the other 3 groups (P < 0.01). CONCLUSION: In patients with GR combined with NCCL, TUN surgery can obviously improve keratinized gingival width and thickness. GRD has a greater effect on the outcome of root coverage than LD, suggesting that NCCL restoration before TUN surgery may not be necessary. Both GRD and LD should be considered in the evaluation of the clinical efficacy of TUN surgery.