Department of Oral and Maxillofacial Surgery, University of São Paulo, São Paulo, Brazil.
J Craniomaxillofac Surg. 2011 Jan;39(1):73-8. doi: 10.1016/j.jcms.2010.03.006. Epub 2010 Apr 24.
This study evaluated the healing of mandibular condylar fracture in rats submitted to experimental and protein undernutrition (8% of protein) by means of histological analysis.
Forty-five adult Wistar rats were divided into three groups of 15 animals: a fracture group, who were submitted to condylar fracture with no changes in diet; an undernourished fracture group, who were submitted to a low protein diet and condylar fracture: an undernourished group, kept until the end of experiment, without condylar fracture. Displaced fractures of the right condyle were created under general anaesthesia. The histological study comprised fracture site and temporomandibular joint evaluations.
The undernourished fracture group showed significant weight loss. There was a marked decrease in the values of serum proteins and albumin in the undernourished fracture group. Histological analysis showed that protein undernutrition lead to atrophy of the condylar fibrocartilage. Fractures in undernutrition presented a delay in callus formation due to more extensive devitalized bone areas, and after 3 months there were still bone formation areas, while fibrous ankylosis occurred in the articular space.
It was concluded that mandibular condyle fractures in rats with protein undernutrition had impaired callus formation, as well as fibrous ankylosis into the temporomandibular joint.
本研究通过组织学分析评估了实验性和蛋白质缺乏（蛋白质 8%）大鼠下颌骨髁突骨折的愈合情况。
45 只成年 Wistar 大鼠分为三组，每组 15 只：骨折组，未改变饮食，行髁突骨折；营养不良性骨折组，行低蛋白饮食和髁突骨折；未骨折组，保持至实验结束，未行髁突骨折。在全身麻醉下创建右侧髁突移位性骨折。组织学研究包括骨折部位和颞下颌关节评估。
营养不良性骨折组体重明显减轻。营养不良性骨折组血清蛋白和白蛋白值明显下降。组织学分析显示，蛋白质缺乏导致髁突纤维软骨萎缩。营养不良性骨折的骨痂形成延迟，因为有更多的失活骨区，3 个月后仍有骨形成区，而关节腔内发生纤维性强直。
结论：蛋白质缺乏的大鼠下颌骨髁突骨折的骨痂形成受损，以及纤维性强直进入颞下颌关节。
