Dong Chenbin, Zheng Shan
Department of Plastic Surgery, Children's Hospital of Fudan University, Shanghai 201102, China.
Department of Plastic Surgery, Children's Hospital of Fudan University, Shanghai 201102, China.
Int J Pediatr Otorhinolaryngol. 2015 Dec;79(12):2208-12. doi: 10.1016/j.ijporl.2015.10.005. Epub 2015 Oct 17.
To characterize the fiber-type distribution of the orbicularis oris muscle at the philtrum in healthy infants by immunohistochemistry and examine the relationship between orbicularis oris and philtrum structure.
Samples of the upper lip were obtained from two infant cadavers. Serial sagittal sections were obtained at the midline of the philtral dimple, unilateral philtral ridge, and the lateral side. Three sections from each site were prepared for immunohistochemical staining using myosin heavy chain fast fiber (MHCf) and myosin heavy chain slow fiber (MHCs) antibodies to determine the ratio of fast to slow skeletal muscle fibers.
The ratio of fast to slow muscle fibers differed significantly among the superficial orbicularis oris muscle (98.30%:1.13%), deep pars peripheralis (95.30%:3.14%), and deep pars marginalis (91.31%:5.74%), with a significantly higher percentage of slow fibers in the pars marginalis compared to pars peripheralis (P=0.002) and fast fibers in the superficial muscle compared to pars marginalis and peripheralis (both P=0.000). Similarly, the fast:slow fiber ratio differed among the superficial philtral dimple (95.88%:2.41%), superficial philtral ridge (98.52%:1.11%), and superficial midlateral philtral ridge (99.07%:0.66%), with a higher percentage of fast fibers higher on the lateral side of the superficial philtral ridge than at the philtral ridge (P=0.030) and higher at the philtral ridge than the philtral dimple (P=0.001). The fast:slow fiber ratio did not differ within the pars peripheralis at the philtral dimple (93.94%:4.19%), philtral ridge (94.49%:3.84%), and lateral philtral ridge (95.79%:2.70%) (all P>0.05).
Philtum structure is likely determined in part by the distribution of muscle fiber types among philtral dimple, ridge, and lateral side. These differences should be considered in cleft lip repair.
通过免疫组织化学方法描述健康婴儿人中处口轮匝肌的纤维类型分布，并研究口轮匝肌与人中结构之间的关系。
从两具婴儿尸体获取上唇样本。在人中凹、单侧人中嵴和外侧的中线处获取连续矢状切片。每个部位的三张切片用于使用肌球蛋白重链快肌纤维（MHCf）和肌球蛋白重链慢肌纤维（MHCs）抗体进行免疫组织化学染色，以确定快肌与慢肌骨骼肌纤维的比例。
口轮匝肌浅层（98.30%:1.13%）、深层外周部（95.30%:3.14%）和深层边缘部（91.31%:5.74%）的快肌与慢肌纤维比例差异显著，边缘部的慢肌纤维百分比显著高于外周部（P = 0.002），浅层肌肉的快肌纤维百分比显著高于边缘部和外周部（P均 = 0.000）。同样，人中凹浅层（95.88%:2.41%）、人中嵴浅层（98.52%:1.11%）和人中中外侧嵴浅层（99.07%:0.66%）的快肌与慢肌纤维比例不同，人中嵴浅层外侧的快肌纤维百分比高于人中嵴处（P = 0.030），人中嵴处高于人中凹（P = 0.001）。人中凹处外周部（93.94%:4.19%）、人中嵴处（94.49%:3.84%）和人中外侧嵴处（95.79%:2.70%）的快肌与慢肌纤维比例无差异（P均>0.05）。
人中结构可能部分由人中凹、嵴和外侧的肌纤维类型分布决定。在唇裂修复中应考虑这些差异。
