Neuromuscular and skeletal adaptations following mandibular counterclockwise rotation accompanied by intrusion of molars with Skeletal Anchorage System (SAS) in Implant-Orthodontics

Skeleton Anchorage System（SAS）是一种新型的正畸治疗中牙齿移动的支抗系统。它由临时植入基底骨中作为固定锚定的钛微型板组成。虽然传统的机械疗法很难使牙齿远移和侵入，但SAS更容易实现。对于SAS，下颌骨逆时针旋转，伴随着磨牙的侵入，可以改善前牙开牙合。然而，正畸压低磨牙改变垂直方向对咀嚼肌活动和牙骨适应性的影响尚不清楚。本文介绍了SAS的概况，并对SAS在前牙开牙合患者种植正畸治疗过程中的形态和功能变化进行了评价。通过治疗前后拍摄的头颅侧位片评估牙颌形态。牙合接触面积 ...更多信息 测量咬合压力、咬合力、咀嚼效率、部分咀嚼肌肌电图（EMG）活动水平和下颌运动描记器（MKG）咀嚼运动。将前牙开牙合患者的结果与正常对照者的结果进行比较。头影测量评价显示，在治疗过程中，上，下后牙，下颌骨逆时针旋转和前面的高度（垂直咬合尺寸）显着下降的入侵。治疗前开患者咀嚼效能、咬合力及接触面积均显著低于对照组。患者的咀嚼肌活动在紧握和咀嚼时相对较低。治疗后，咀嚼效率、咬合力和咬合接触面积有所增加，但仍明显低于对照组水平。咀嚼肌协调地工作着，它们的活跃度要高得多。这项研究的结果表明，在开牙合患者，咀嚼系统的功能受损和正畸矫正的侵入磨牙SAS改善形态和功能缺陷。需要更大的样本来证实这些发现。少

The Skeletal Anchorage System (SAS) was newly developed for tooth movements in orthodontic treatment. It consists of titanium miniplates which are temporarily implanted in the basal bones as stationary anchorages. Although distalization and intrusion of teeth have been extremely difficult by traditional mechanotherapies, those are more easily achieved by SAS. With SAS, anterior open bite can be improved by the counterclockwise rotation of the mandible, accompanied by the intrusion of molars. However, it has been unknown about the influences of changing the vertical dimension by orthodontic intrusion of molars on masticatory muscle activities and dentoskeletal adaptations. In this paper, we introduced an outline of SAS and evaluated morphological and functional changes produced during the Implant-Orthodontics treatment with SAS in the anterior openbite patients. The dentoskeletal morphology was assessed through lateral cephalograms taken before and after treatment. Occlusal contact area … More , occlusal pressure, bite force, masticatory efficiency, levels of electromyogram (EMG) activity in some of the muscles of mastication, and chewing movement by mandibular kinesiograph (MKG) were measured on all subjects. The results in patients with anterior openbite were compared with those in controls with normal occlusion. Cephalometric evaluation revealed intrusion of upper and lower posterior teeth, counterclockwise rotation of the mandible and a significant decrease of anterior facial height (vertical occlusal dimension) during treatment. Before treatment, the openbite patients had masticatory efficiency, bite force and occlusal contact area significantly less than those of controls. The patients' masticatory muscle activity was relatively low during clenching and chewing. After treatment, masticatory efficiency, bite force and occlusal contact area increased, but they were still significantly lower than the control subject level. The masticatory muscles were working harmoniously, and their activity was much higher. The results of this study suggest that in openbite patients, function of the masticatory system is impaired and orthodontic correction by intrusion of molars with SAS improves both the morphological and functional deficits. A larger sample is needed to confirm these findings. Less