Teixeira Vanessa C B, Teixeira Antonio C B, Luz João Gualberto C
Department of Oral and Maxillofacial Surgery, University of São Paulo, São Paulo, Brazil.
J Craniomaxillofac Surg. 2006 Jun;34(4):220-5. doi: 10.1016/j.jcms.2006.01.006. Epub 2006 Apr 25.
Fractures of the mandibular condyle are common. A potential for growth disturbances in young individuals has been reported; however, there are few experiments studying such consequences. Skeletal changes after fracture of the condyle in the growing period were analysed in this study.
Fifty young Wistar rats weighing 100g were used. Under general anaesthesia unilateral fracture dislocations of the condylar process were induced surgically in the experimental group (n=25), while only surgical access was performed in the sham-operated group. The animals were sacrificed at 3 months of age. The mandibles were disarticulated, and radiographs were taken (axial skulls and lateral hemimandibles). Cephalometric evaluations were made using a computer system. Statistical tests were applied between groups and contralateral sides in each group.
There were atrophy and degenerative change of the fractured condylar process. There was also a significant difference in the height of the mandibular body and in the length of anterior and posterior maxilla.
It was concluded that an experimental fracture of the mandibular condyle during the growing period in rats induced degenerative changes of the condyle as well as an asymmetry of the mandible, affecting height of the body, also leading to consequences in the maxilla.
下颌髁突骨折很常见。有报道称年轻个体存在生长发育紊乱的可能性;然而,很少有实验研究此类后果。本研究分析了生长期髁突骨折后的骨骼变化。
使用50只体重100克的年轻Wistar大鼠。在全身麻醉下,对实验组(n = 25)进行手术诱导单侧髁突骨折脱位,而假手术组仅进行手术切开。动物在3个月龄时处死。分离下颌骨,拍摄X线片(颅骨正位和半侧下颌骨侧位)。使用计算机系统进行头影测量评估。对组间以及每组的对侧进行统计学检验。
骨折的髁突出现萎缩和退行性改变。下颌体高度以及上颌前后长度也存在显著差异。
得出的结论是,大鼠生长期下颌髁突的实验性骨折会导致髁突退行性改变以及下颌骨不对称,影响下颌体高度,也会对上颌产生影响。