Mechanobehavior distinguishes mandibular growth differences in two facial types

机械行为区分两种面部类型的下颌生长差异

• 批准号: 10664884
• 负责人: Laura R Iwasaki
• 金额: $ 55.89万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10664884
• 关键词: 20 year old; Address; Affect; Animals; Behavior; Benchmarking; Cartilage; Categories; Cells; Child; Childhood; Clinical; Clinical Treatment; Controlled Study; Data; Dental; Dental Care; Dimensions; Electromyography; Environment; Exclusion; Extracellular Matrix; Face; Failure; Financial cost; Foundations; Frequencies; Future; Goals; Growth; Health; Height; Heterogeneity; Human; Individual; Jaw; Knowledge; Laboratories; Malocclusion; Mandible; Mandibular Condyle; Measurable; Measures; Mechanics; Methods; Mission; Mitotic; Modeling; Morbidity - disease rate; Muscle; Observational Study; Operative Surgical Procedures; Oral; Orthodontic; Orthopedics; Outcome; Outcome Measure; Outcomes Research; Patient Noncompliance; Patients; Persons; Phenotype; Population; Prognosis; Protocols documentation; Quality of life; Records; Research; Risk; Role; Shapes; Social Well-Being; Subgroup; Techniques; Technology; Temporomandibular Joint; Testing; Time; Tooth structure; Treatment Cost; United States; Work; age group; aged; bullying; cost; craniofacial; dentofacial; energy density; improved; in vivo; joint loading; mechanical load; novel; orthognathic; personalized approach; prospective; psychosocial; skeletal; success; systematic review

In the United States, >9% of children are orthodontic patients who are treated for crooked teeth and jaw discrepancies known as malocclusions (AAO, 2017). Costs for this treatment are >$9.5 billion annually (Guay et al. 2008; Laniado et al. 2017). Management of jaw growth via dentofacial orthopedics is indicated in >30% of orthodontic patients but 13-36% of mandibular growth enhancement therapies fail to correct the malocclusion (Hedlund and Feldmann 2016; O'Brien et al. 2003). Hence, the costs of poor results are considerable. Orthopedic therapies for mandibular enhancement try to promote growth of the load-sensitive secondary cartilages of the jaw through changes in temporomandibular joint (TMJ) loading mechanics and behaviors. Mandibular growth is expected to be less in amount and expressed more vertically (Buschang et al. 2017; Karlsen 1997) with poorer prognoses for orthopedic therapies in children with dolichofacial (long-narrow) compared to brachyfacial (short-wide) phenotypes (Deen and Woods 2015; Pancherz and Michailidou 2004; Rogers et al. 2018). However, differences in the TMJ loading mechanics and behaviors (mechanobehavior) in these phenotypes during growth and treatment are unknown. The broad, long-term goals of this research are to provide evidence-informed dentofacial orthopedic therapies with predictable results. Thus, this application proposes a prospective observational study in selected populations of dolichofacial and brachyfacial children before, during and after orthodontic treatment. This study will contribute to the mission of improving dental, oral, and craniofacial health by addressing three Specific Aims: 1. Test the hypothesis that dolichofacial compared to brachyfacial children have energy densities (energy input per volume of cartilage, mJ/mm3) that are significantly larger for the same jaw tasks and, thus, limit mandibular growth earlier. 2. Test the hypothesis that dolichofacial compared to brachyfacial children have duty factors (% time of jaw muscle activity/total recording time) that are significantly smaller and, thus, promote less mandibular growth per year. 3. Test the hypothesis that phenotypic dentofacial subgroups exist, differentiated by mechanobehavior scores ((energy densities)2 X duty factors) that correspond with significant differences in mandibular growth. Longitudinal clinical treatment records and data collected via validated techniques, including numerical modeling, dynamic stereometry, and laboratory and in-field electromyography, will be used to compare mechanobehavior variables between phenotypes and test if these variables predict mandibular growth as indicated by ramus height. The novel outcomes of this research will be critical foundations for future clinical approaches that modify mechanobehavior to achieve more successful and predictable orthopedic therapies in children with jaw discrepancies.

在美国，超过 9% 的儿童是因牙齿和下颌不正而接受治疗的正畸患者 称为咬合不正的差异（AAO，2017）。这种治疗的费用每年超过 95 亿美元（Guay 等人。 2008年；拉尼亚多等人。 2017）。超过 30% 的人表示通过牙颌面矫形术管理颌骨生长 正畸患者，但 13-36% 的下颌生长促进疗法未能纠正咬合不正 （Hedlund 和 Feldmann，2016 年；O'Brien 等人，2003 年）。因此，不良结果的代价是相当大的。 下颌增强的骨科治疗尝试促进负载敏感的次级骨的生长 通过改变颞下颌关节 (TMJ) 负载力学和行为来改变颌骨软骨。 预计下颌生长量会减少，并且会更加垂直（Buschang et al. 2017； Karlsen 1997）对于长颌面（长窄型）儿童的骨科治疗预后较差 与短面（短宽）表型相比（Deen 和 Woods 2015；Pancherz 和 Michailidou 2004； 罗杰斯等人。 2018）。然而，TMJ 加载机制和行为（机械行为）的差异 生长和治疗期间的这些表型是未知的。这项研究的广泛、长期目标是 提供具有可预测结果的循证牙面矫形治疗。因此，本申请 提出对选定的长面部和短面部儿童群体进行一项前瞻性观察研究 正畸治疗之前、期间和之后。这项研究将有助于改善牙科、 通过实现三个具体目标来实现口腔和颅面健康： 1. 检验以下假设：与短面儿童相比，长面儿童具有能量密度（能量输入 每单位软骨体积 (mJ/mm3) 对于相同的下颌任务而言明显更大，因此限制 下颌生长较早。 2. 检验以下假设：与短面儿童相比，长面儿童具有责任因子（下巴时间百分比） 肌肉活动/总记录时间）明显较小，因此促进下颌生长较少 每年。 3. 检验表型牙面部亚群存在的假设，并通过机械行为评分进行区分 （（能量密度）2 X 占空比）与下颌生长的显着差异相对应。 通过验证技术收集的纵向临床治疗记录和数据，包括数值 将使用建模、动态立体测量以及实验室和现场肌电图来比较 表型之间的机械行为变量，并测试这些变量是否预测下颌生长 由支高度表示。这项研究的新成果将为未来的临床研究奠定重要基础 改变机械行为的方法，以实现更成功和可预测的骨科治疗 下颌差异的儿童。