Objective To study the repair effect of low intensity pulsed ultrasound（LIPUS） irradiating combined with guided bone regeneration（GBR） on the defect of Beagle dog canines periodontal bone. Methods Four canine teeth of every beagle dog（8 beagle dogs） were randomly distributed: Group 1（LIPUS disposal + GBR+ autogenous bone graft group）, group 2（LIPUS disposal + autogenous bone graft group）, group 3（GBR + autogenous bone graft group）, blank control group. The model of periodontal bone defect was established in the 1/3 part of the root buccal area. According to the group division, autogenous bone were grafted, group 1 and group 2 were disposed by LIPUS 20 min·d-1. The intensity of ultrasound were 30 mW·cm-2. Group 1 and group 3 were injected with Bio-Gide collagen membrane. The beagle dogs were executed at 6 and 8 weeks of the disposal of LIPUS and then Micro-CT test and analysis were conducted to periodontal bone defect area of each group. Results By clinical observation, there were different degrees of shrinkages of the area of periodontal bone defect in each group. The Micro-CT test analysis indicated that there was a statistical difference among the number, the thickness as well as the size of bone trabecula of each group
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