[Clinical applications of transcrestal around detached sinus floor elevation technique using osteotomes and sequential drills with stops].

Sinus floor elevation was needed in 11 patients having 15 implant sites with the residual bone height (RBH) was less than 10 mm in the posterior maxillary region from Feb to May 2017. The RBH ranged from 3.10 to 8.34 mm [averaged (6.18±1.60) mm]. RBH<6 mm was observed in 40% implant sites (6 implant sites) and RBH≥6 mm was observed in 60% implant sites (9 implant sites). The thickness of the sinus floor membrane correspond to the implant site measured by cone beam CT (CBCT) ranged from 0.50 to 4.24 mm [averaged (1.21±0.92) mm]. Sequential drills with stops were used to perforate the cortical bone of the sinus floor firstly, then the transcrestal around detached sinus floor elevation technique (TADSFET) was carried with osteotomes. Anorganic bovine bone was used as the augmentation material.Fifteen implants were placed in 15 implant sites. CBCT pictures showed that there was a smooth and continuous tent-shaped apophysis on each lifted site and no air fluid level was observed in the sinus immediately after operation. The mean elevated height of the 15 implant sites was (7.83±1.57) mm (ranged from 5.94 to 11.01 mm). The mean follow-up time was 7.91 months (7-10 months). The survival rate was 100% during the follow up period.