Rowshan Henry H, Parham Mary A, Baur Dale A, McEntee RaeLynn D, Cauley Eugene, Carriere Dane T, Wood Joseph C, Demsar William J, Pizarro Jose M
Oral and Maxillofacial Surgery, Ft Irwin, CA, USA.
J Oral Maxillofac Surg. 2010 Feb;68(2):260-7. doi: 10.1016/j.joms.2009.09.045.
To establish a rat mandibular fracture model and investigate the short- and long-term effects of recombinant parathyroid hormone (PTH 1-34) on mandibular fracture healing in rats.
A controlled unilateral mandibular fracture was created surgically in 29 male Sprague-Dawley rats and then stabilized using an external fixation device. The rats were divided into 2 groups: 1 group received daily subcutaneous injections of 10 microg/kg of PTH(1-34) and 1 group served as the vehicle control. The rats were killed on postoperative days 7 and 21, and radiographic densitometry and histologic evaluation of new bone formation were performed.
A novel unilateral mandibular fracture model was established that has significant differences from previously published models, both in the location of the osteotomy site and in the rigid external stabilization device. The PTH(1-34) treated rats showed a statistically significant difference (P < .05) in callous formation compared with the control animals. Radiographic densitometry evaluation of the injury site revealed an increase in bone density, apparent at day 7 in the experimental group. Visual inspection of the histologic sections stained with Masson's trichrome blue showed an apparent increase in new bone formation at 21 days in the PTH-treated group compared with the control group.
Intermittent systemic administration of PTH(1-34) might enhance the healing of mandibular fractures in the early phase (7-day period). Long-term administration (21-day period) showed no statistically significant differences between the control and experimental group by radiographic densitometry.
建立大鼠下颌骨骨折模型，研究重组甲状旁腺激素（PTH 1-34）对大鼠下颌骨骨折愈合的短期和长期影响。
对29只雄性Sprague-Dawley大鼠进行手术造成可控性单侧下颌骨骨折，然后使用外固定装置进行固定。将大鼠分为2组：1组每天皮下注射10μg/kg的PTH(1-34)，1组作为溶剂对照组。在术后第7天和第21天处死大鼠，进行放射密度测定和新骨形成的组织学评估。
建立了一种新型单侧下颌骨骨折模型，该模型在截骨部位和刚性外固定装置方面与先前发表的模型有显著差异。与对照动物相比，PTH(1-34)治疗的大鼠在骨痂形成方面有统计学显著差异（P <.05）。对损伤部位的放射密度测定评估显示骨密度增加，在实验组第7天明显可见。用Masson三色蓝染色的组织学切片目视检查显示，与对照组相比，PTH治疗组在21天时新骨形成明显增加。
间歇性全身给予PTH(1-34)可能会促进下颌骨骨折在早期阶段（7天期间）的愈合。通过放射密度测定，长期给药（21天期间）在对照组和实验组之间未显示出统计学显著差异。
