Abstract：
OBJECTIVE: The aim of the study was to determine how the electrical activity of the temporalis, masseter and sternocleidomastoid muscles differs in children with reduced transverse jaw dimension compared to children with normal occlusion.
METHODS: It was a experimental study. Thirty-seven patients were included in the study. 18 in the study group received orthodontic treatment with removable appliances and 19 subjects were classified as normal occlusion subjects in the control group. A panoramic X-ray and digital intraoral scan were taken, followed by an surface electromyography of three muscle pairs (temporalis muscles, masseter muscles, sternocleidomastoid muscles) in resting position, while clenching and clenching on cotton rollers.
RESULTS: There was significantly greater activity in the experimental group than in the control group comparing muscles: temporalis muscles and masseter muscles in the resting position. Additionally, significantly greater activity of muscles in the control group was found during clenching. However, the asymmetry index of muscles indicates that there is significantly greater asymmetry of muscles activity in the experimental group. Compared to children with normal occlusion, children with a narrowed transverse dimension of the jaw have statistically significant differences in the bioelectrical activity of the temporalis, masseter and sternocleidomastoid muscles, as well as greater asymmetry in the bioelectrical voltage of the masseter muscles.
CONCLUSIONS: Patients with reduced transverse dimension of the jaw are characterized by increased resting activity of the masticatory muscles and reduced functional activity of the masticatory muscles. These patients have increased asymmetry in the bioelectrical tension of the masticatory muscles.
METHODS: It was a experimental study. Thirty-seven patients were included in the study. 18 in the study group received orthodontic treatment with removable appliances and 19 subjects were classified as normal occlusion subjects in the control group. A panoramic X-ray and digital intraoral scan were taken, followed by an surface electromyography of three muscle pairs (temporalis muscles, masseter muscles, sternocleidomastoid muscles) in resting position, while clenching and clenching on cotton rollers.
RESULTS: There was significantly greater activity in the experimental group than in the control group comparing muscles: temporalis muscles and masseter muscles in the resting position. Additionally, significantly greater activity of muscles in the control group was found during clenching. However, the asymmetry index of muscles indicates that there is significantly greater asymmetry of muscles activity in the experimental group. Compared to children with normal occlusion, children with a narrowed transverse dimension of the jaw have statistically significant differences in the bioelectrical activity of the temporalis, masseter and sternocleidomastoid muscles, as well as greater asymmetry in the bioelectrical voltage of the masseter muscles.
CONCLUSIONS: Patients with reduced transverse dimension of the jaw are characterized by increased resting activity of the masticatory muscles and reduced functional activity of the masticatory muscles. These patients have increased asymmetry in the bioelectrical tension of the masticatory muscles.
摘要：
目的：本研究的目的是确定颞肌的电活动与正常咬合儿童相比，横向颌骨尺寸减小的儿童咬肌和胸锁乳突肌不同。
方法：这是一项实验研究。37名患者被纳入研究。研究组中的18名接受了可移动矫治器的正畸治疗，对照组中的19名受试者被归类为正常咬合受试者。进行了全景X射线和数字口腔内扫描，然后是三个肌肉对的表面肌电图(颞肌，咬肌,胸锁乳突肌)处于静止位置，同时紧握和紧握棉辊。
结果：实验组的活动明显大于对照组的肌肉：在静息位置的颞肌和咬肌。此外,在紧握过程中，对照组的肌肉活动明显更大。然而,肌肉的不对称指数表明实验组肌肉活动的不对称性明显更大。与正常闭塞儿童相比，颌骨横向尺寸狭窄的儿童在颞肌的生物电活动方面具有统计学上的显着差异，咬肌和胸锁乳突肌，以及咬肌的生物电电压更大的不对称性。
结论：颌骨横向尺寸减小的患者的特征是咀嚼肌的静息活动增加和咀嚼肌的功能活动减少。这些患者咀嚼肌的生物电张力的不对称性增加。
方法：这是一项实验研究。37名患者被纳入研究。研究组中的18名接受了可移动矫治器的正畸治疗，对照组中的19名受试者被归类为正常咬合受试者。进行了全景X射线和数字口腔内扫描，然后是三个肌肉对的表面肌电图(颞肌，咬肌,胸锁乳突肌)处于静止位置，同时紧握和紧握棉辊。
结果：实验组的活动明显大于对照组的肌肉：在静息位置的颞肌和咬肌。此外,在紧握过程中，对照组的肌肉活动明显更大。然而,肌肉的不对称指数表明实验组肌肉活动的不对称性明显更大。与正常闭塞儿童相比，颌骨横向尺寸狭窄的儿童在颞肌的生物电活动方面具有统计学上的显着差异，咬肌和胸锁乳突肌，以及咬肌的生物电电压更大的不对称性。
结论：颌骨横向尺寸减小的患者的特征是咀嚼肌的静息活动增加和咀嚼肌的功能活动减少。这些患者咀嚼肌的生物电张力的不对称性增加。
