Clinical study on changes and adaptations of physiological functions after orthognathic surgery

A)颏舌肌（GG）表现出与强直活动叠加的阶段性吸气活动，以维持上呼吸道（UA）通畅。然而，具有呼吸相关活性的单个GG运动单元（MU）的放电特性仍有待确定。记录了8例成年男性在自然头位和30个俯卧位下自发性鼻呼吸时24只GG mu的单单位活动。吸气MU （IMU）表现为吸气时的相性活动，而吸气-呼气MU （IEMU）表现为吸气时的相性活动叠加在强直活动上。30个俯卧位吸气时IMU的放电持续时间和瞬时放电频率（1FF）显著增加。虽然IEMU的1FF在30个俯卧位也显著增加，但吸气期和呼气期之间没有显著差异。尖峰间期分析表明，IMU和IEMU的功能差异较大。B)(1)为了研究下颌骨前突患者在手术或通颌手术后口咽结构的形态学变化，我们选取了25例接受过手术或通颌治疗的下颌骨前突患者。术前、术后3个月、6个月、1年各获得一组4张标准化侧位脑电图。UA结构的形态学变化按性别纵向评估。在3个月和6个月时，男女咽部前后宽度参数均明显下降，女性术后1年这些参数趋于恢复到术前值，而男性则没有。男性术后1年舌骨骨明显下降，女性无明显变化。男性术后舌骨与第三椎体之间的距离逐渐减小；然而，在女性中没有明显的变化。男性下咽的横截面积在术后1年明显减少，而女性则没有。这些结果表明，手术后男性和女性UA形态发生了不同的变化。为了补偿手术后的骨骼变化，男性和女性似乎以不同的方式对保留功能性UA做出反应。(2)选取7例成人下颌前凸伴开咬不对称患者，提取其保留时牙面三维特征变化，明确影响术后咬合稳定性的形态学因素。使用侧位和额位头颅图三维分析固位期间义齿和骨骼成分的变化以及前牙合。结果表明，在三维牙面畸形患者中，保持前牙合在垂直维度上的长期稳定是非常重要的。c)(1)为了探讨性别、年龄、关节活动能力等病因与颞下颌关节（TMJ）紊乱的关系，我们选择了110例正畸患者。78名女性中有50人，32名男性中有17人有颞下颌关节紊乱症状。在颞下颌关节疾病的患病率方面，没有观察到显著的性别差异。而女性患者出现颞下颌关节、肌肉疼痛和开口困难的频率高于男性患者。随着年龄的增长，TMJ疾病的相对风险显著增加。一般关节活动度得分越高，患颞下颌关节疾病的风险也越高。(2)采用问卷调查和牙模法对174例颌骨畸形患者颞下颌关节紊乱的发生率进行调查。报告的目前或过去TMJ疾病的频率为77.6%。没有观察到性别差异。不同年龄组的颞下颌关节疾病发生频率以年龄最小的15岁次之，每隔5年增加一次，各年龄组间无显著差异。在135例有症状的患者中，49例（36.3%）仅报告一种TM疾病症状，86例（63.7%）报告两种及两种以上症状。在潜在病因和历史事件方面，有症状患者体位不良和创伤经历的发生率高于无症状患者。不同咬合形态类型的颞下颌关节病变发生率无显著差异。少

A) The genioglossus (GG) muscle shows a phasic inspiratory activity superimposed on tonic activity to maintain upper airway (UA) patency. However, discharge properties of single GG motor unit (MU) with respiratory-related activity remain to be determined. Single unit activities of 24 GG MUs with respiratory-related discharge were recorded during spontaneous nasal breathing in both the natural head position and 30ﾟ head-up position in 8 adult males. The inspiratory MU (IMU) showed the phasic activity during inspiration, whereas the inspiratory-expiratory MU (IEMU) showed the phasic inspiratory activity superimposed on the tonic activity. The firing duration and instantaneous firing frequency (1FF) of the IMU during inspiration significantly increased in the 30ﾟ head-up position. Although the 1FF of the IEMU also significantly increased in the 30ﾟ head-up position, there was no significant difference between inspiratory and expiratory phases. An interspike interval analysis demonstrated … More that the functional divergence of the IMU and IEMU.B) (1) To investigate morphologic changes in oropharyngeal structures in mandibular prognathic patients after or thognathic surgery, 25 patients with mandibular prognathism who had undergone surgical and or thognathic treatment were used. A set of 4 standardized lateral cephalograms were obtained from each subject preoperatively and at 3 months, 6 months, and I year postoperatively. Morphologic changes in UA structures were evaluated longitudinally by gender. Parameters of the anteroposterior width of the pharynx significantly decreased at 3 and 6 months in both genders, and these parameters tended to rebound to the preoperative values 1 year postoperatively in females, but not in males. The hyoid hone significantly descended inferiorly 1 year postoperatively in males, white there were no significant changes in females. The distance between the hyoid bone and the third vertebra gradually decreased in males postoperatively ; however, there were no significant changes in females. The cross-sectional area of the hypopharynx significantly decreased 1 year postoperatively in males, but not in females. These results indicate that the UA morphology changed differently in males and females following surgery. To compensate fro skeletal changes following surgery, it appears that males and females responded in differently ways to preserve a functional UA.(2) To extract characteristic three-dimensional dentofacial changes during retention and to clarify morphological factors affecting the stability of postoperative occlusion in mandibular prognathic patients with open bite and asymmetry, 7 adult patients were used. Changes in denture and skeletal components, and anterior occlusion during retention were analyzed three-dimensionally using the lateral and frontal cephalograms. Results indicated that it was important to maintain long-term stability of the anterior occlusion in the vertical dimension in patients with three-dimensional dentofacial deformity.C) (1) To investigate the relationship between the etiologic factors such as gender, age, and general joint mobility and temporomandibular joint (TMJ) disorders, 110 orthodontic patients were used. Fifty of 78 females and 17 of 32 males showed symptoms of TMJ disorders. No significant gender difference was observed in the prevalence of TMJ disorders. However, TMJ and muscular pain and difficulty in mouth opening were more frequently observed in female symptomatic patients than male patients. There was a significant relative risk of TMJ disorders associated with increasing age. Higher score of general joint mobility was also significantly associated with an increased risk of TMJ disorders. (2) The frequency of TMJ disorders in 174 patients with jaw deformities was surveyed by questionnaires and dental casts. The frequency of reported present or past TMJ disorders was 77.6%. No difference by gender was observed. When the frequency of TMJ disorders in different age groups was examined, the youngest being 15 years of age followed by others at increasing age intervals of 5 years, there was no significant difference between age groups. Among 135 symptomatic patients, 49 patients (36.3%) reported only one symptom of TM) disorders, while 86 patients (63.7%) reported two or more symptoms. As for potential etiologic factors and historical events, poor posture and experience of trauma were more frequently observed among symptomatic patients than asymptomatic patients. There was no significant difference in the frequency of TMJ disorders between different occlusomorphologic types. Less