Methods Newly designed trephine cord, double trephine guide, posterior longitudinal ligament removal hooker and U shaped chisel were applied in 56 cases of cervical spondylosis among which 113 were companied by radiopathy and 7 were companied by OPLL; 43 cases were performed with single level decompression, 11 cases were performed with double level decompression and 2 cases with three level.

Clinical application of maxillary sinus lift with Summers osteotome;