[Clinical study on united crowns or bridges for restoration of posterior teeth with insufficient maxillary bone by means of maxillary tuberosity dental implants].

Perpose: To evaluate the clinical effect of united crowns or bridges for restoration of posterior teeth with insufficient maxillary bone by means of tilted dental implants.

Methods: Patients who underwent dental implant surgery in posterior teeth with insufficient maxillary bone were collected and divided into two groups (40 in each group). Patients in the experimental group were treated with titled dental implantation, while patients in the control group were treated with maxillary sinus lifting. Implant retention, marginal bone loss, incidence of adverse reactions, time needed for implantation and cost were recorded and analyzed with SPSS 19.0 software package.

Results: After follow up of 2 year, the experimental group had a cumulative survival rate of 100%, marginal bone resorption was (0.31±0.27)mm on average, no sinusitis and massive haemorrhage were noted, The control group had a cumulative survival rate of 96.43%, marginal bone resorption was (0.28±0.26) mm on average, sinusitis and massive haemorrhage occurred in 9.5%,4.8% of patients, the difference was not statistically significant（P＞0.05）. In the experimental group, maxillary sinus mucosa perforation and postoperative pain occurred in 0%,7.5% of patients, duration of operation was （30.55±8.21）min, average cost of each implant was （6.9±0.5）thousand RMB; while in the control group, maxillary sinus mucosa perforation and postoperative pain occurred in 14.3%,28.6% of patients, duration of operation was （50.32±10.80）min, average cost of each implant was (0.98±0.06) thousand RMB, the difference was significant（P＜0.05）.

Conclusions: It is feasible to use united crowns or bridges for restoration of posterior teeth with insufficient maxillary bone by means of maxillary tuberosity dental implants.