Objective: To investigate the influence of enucleation with or without orbital implant on the occurrence of apoptosis of orbital osteocytes and to explore the mechanism of orbital implant in the prevention and treatment of orbital malformations.
Methods: It was an experimental research. Twenty-one age and weight-matched New Zealand rabbits were divided into three groups: enucleation group, enucleation with implant group and the control group. At one-month-old, the left eyes of the rabbits were enucleated in the enucleation group; an orbital implant was inserted after enucleation in the implant group. The left orbits of rabbits in the control group were served as the controls. At two-month-old, all rabbits were sacrificed, apoptosis of osteocytes of the zygomatic bones was observed by photomicroscopy, electron microscopy and TUNEL staining technology. The ratios of apoptosis osteocytes were calculated and analyzed in these three groups.
Results: Classical apoptosis of osteocytes was found with photomicroscopy and electron microscopy. The distribution of apoptosis of osteocytes was irregular in bone sections. The ratio of apoptosis cells in the enucleation group was significantly different from that in the other two groups (P<0.01). There was no significant difference in ratios of apoptosis cells between the implant group and the controls (P>0.05).
Conclusions: Apoptosis of osteocytes participates in the normal development of bony orbit. The results of this study indicate that apoptosis of osteocytes plays a role in the development of orbital malformation after enucleation and orbital implant can prevent the orbital malformation after enucleation.