To study the effect of periostin gene on bone regeneration and mineralisation during distraction osteogenesis (DO) in a rabbit mandibular model.

A total of 54 New Zealand white rabbits underwent mandibular lengthening and were divided into group A and group B (n=27, each). At the end of the distraction, adenoviruses containing human POSTN/enhanced green fluorescent protein (Ad5-POSTN/EGFP) viruses or Ad5-POSTN viruses were injected into the distraction gaps in the group B or A, respectively. On the 4th and 8th week after distraction, eight samples, randomly selected from each group, were subjected to CT scanning and dual energy X-ray absorptiometry detection. All animals from each group were sacrificed for micro-CT, histology, and three-point bend testing eight weeks after DO.

The CT images showed that callus in the distraction gap of group B was significantly better than that of group A. On the 4th and 8th weeks, the bone mineral densities (BMD) of the bone tissue in the distraction gap of the group B were 0.163±0.011g/cm² and 0.239±0.024g/cm², respectively, while the bone mineral contents (BMC) was 0.099±0.011g and 0.205±0.018g, respectively, which were significantly higher compared with group A. Histological sections showed that the trabecular bone in the distraction gap of group B was more coarse. On the basis of micro-CT images and micro-architecture parameters show that the microstructure of the distraction gap of the group B had more mature characteristics. The biomechanical strength of the distracted gap in the group B was 234.30±30.48N, which was 1.28 times higher than that in the group A (P=0.003).

Local transduction with human periostin gene would promote osteogenesis and mineralisation in a rabbit mandibular DO model. Periostin might be considered for clinical use if only there is a safe and effective administration method.