Effects of proton pump inhibitor FR167356 on osseointegration of dental implant in osteoporosis rabbits / 中国组织工程研究

ABSTRACT

BACKGROUND:Vacuolar proton pump on the cytoplasmic membrane of osteoclasts is an essential enzyme for bone histolysis. Vacuolar proton pump inhibitor can significantly inhibit the in vitro cultured osteoclasts. OBJECTIVE:To observe the effect of proton pump inhibitor FR167356 on the osseointegration of dental implant of osteoporosis rabbits. METHODS:A total of 24 female Japanese white rabbits aged 5 months were randomly divided into three groupsovariectomy (OVX) group, FR167356 group and shamed operation group. Each group contained eight rabbits. Rabbits of OVX group and FR167356 group received a surgical removal of bilateral ovaries, while rabbits of sham operation group had a surgical removal of equivalent adipose tissue beside the ovaries. Two titatium implants (8 mm long, 3.3 mm diameter) were instal ed into bilateral proximal tibias respectively 12 weeks after OVX operation. FR167356 was administrated by muscle injection in FR167356 group;meanwhile equivalent normal saline was administrated in the OVX group and sham operation group. At 4 and 8 weeks after implantation, animals in each group were sacrificed respectively for X-ray imaging, histomorphology, and mechanical test. RESULTS AND CONCLUSION:X-ray examination showed that at 4 weeks, the implants in the OVX group exhibited a high resistance projective image, low density image of clearance screw thread, and clear boundaries between bone tissue than the other two group. At 12 weeks, the density of the clearance screw thread in sham operation group and FR167356 group was more closer to the surrounding bone tissue when compared with the OVX group, the boundaries between the implant and the surrounding bone tissue disappeared more apparently, and no significant differences were found between the two groups. Histomorphology observation revealed that, at 4 weeks after implantation, new bone with porous and trabecular extended along the implant surface to the root direction in FR167356 and sham operation groups. There were no significant differences in the two groups. At 12 weeks after implantation, the bone mass around implant was increased greatly and the trabecular grew thicker. This phenomenon was not observed in the OVX group. Mechanic test showed that at 4 and 12 weeks after implantation, the maximum pul out force in the OVX group was significantly lower than that in the other two groups. Local application of FR167356 can significantly improve the osseointegration of the implant in osteoporosis rabbits.