EARLY VS LATE TREATMENT IN CLASS II MALOCCLUSION

目前，大约50%的美国儿童需要正畸 目前，在许多地区，有35-40%的人接受了治疗。 其中， 近一半的人接受II类错牙合治疗， 其特征在于上门齿的相对突出 但最常见的原因是 生长期的下颌。 这个项目的目标是比较 II类骨性关节炎的三种替代治疗方法 咬合不正（即，II类错牙合，由于不一致， 颌骨生长）：早期正畸治疗，以修改生长 青春期前的颌骨;后期正畸治疗， 重新定位牙齿，并补偿任何下巴的差异， 通常在青春期进行;以及正畸-正畸 治疗，以重新定位颌骨，这通常是保留给 青少年晚期或年轻人的严重问题。 理想情况下，我们将完全在随机临床试验中进行这一研究 (RCT)，但由于时间限制，无法仅使用此 在初始授予期间的方法。 因此，我们将开始一个 RCT研究早期与晚期正畸治疗，以评估 头戴物发生生长改变的程度 和/或功能矫正治疗，并评估影响 口腔健康的早期治疗。 我们还将利用 回顾性和前瞻性数据的观察性研究， 两个目的：（1）获得初步数据，比较这些 治疗方法和（2）比较晚期正畸与 更严重问题的外科手术治疗。 我们 重点将是形态学治疗效果， 达到治疗目标的患者和百分比 改善、对口腔健康的影响以及患者 满意度由效用函数表示。 我们将调查 决策分析技术的潜在用途， 确定在给定条件下的优先处理方法 条件，并将试图确定这些关键因素， 决定 质量的显著提高， 正畸治疗可以通过演示来实现， 其中一种治疗方法在特异性方面具有上级优势 情节

At present, approximately 50% of U.S. children need orthodontic treatment and 35-40% now receive it in many areas. Of these, nearly half are treated for Class II malocclusion, which is characterized by a relative protrusion of the upper incisor teeth but most frequently is caused by an underdevelopment of the lower jaw during growth. The goal of this project is to compare three alternative treatment approaches to skeletal Class II malocclusion (i.e., Class II malocclusion due to a discrepancy in jaw growth): early orthodontic treatment to modify the growth of the jaws prior to adolescence; late orthodontic treatment to reposition the teeth and compensate for any jaw discrepancy, usually done during adolescence; and surgical-orthodontic treatment to reposition the jaw(s), which typically is reserved for severe problems in late adolescents or young adults. Ideally, we would do this entirely in a randomized clinical trial (RCT), but time constraints make it impossible to use only this method in an initial granting period. Therefore, we will begin a RCT to study early versus late orthodontic treatment, to assess the extent to which growth modification occurs with headgear and/or functional appliance treatment, and to assess the impact of early treatment on oral health. We also will utilize an observational study with retrospective and prospective data for two purposes: (1) to obtain preliminary data comparing these treatment methods and (2) to compare late orthodontic versus orthodontic-surgical treatment of the more severe problems. Our focus will be on the morphologic treatment effects, number of patients in whom treatment goals were reached and percent improvement, impact on oral health, and degree of patient satisfaction as indicated by utility functions. We will investigate the potential usefulness of decision analysis techniques to determine the perferred treatment approach under given conditions and will attempt to identify the critical factors in such a decision. A significant improvement in the quality of orthodontic treatment could be achieved by a demonstration that one of the treatment approaches was superior in specific circumstances.