ROOT RESORPTION DUE TO ORTHODONTIC MOVEMENT

描述（由申请人提供）：生理或病理性牙根吸收导致牙根矿化和非矿化组织的破坏。病理性牙根吸收，内部或外部，可能是由于囊肿，肿瘤，创伤，感染，牙周病或正畸治疗的存在。这个过程可能会随着时间的推移而破坏牙根，导致牙齿脱落。根尖吸收是牙周病医生在实践中面临的最常见的问题之一。这个过程可能会损害其他成功的正畸治疗的好处，并可能导致严重的医学法律后果。虽然许多临床和组织学研究已经进行，以阐明外牙根吸收的病因和发病机制，导致牙根吸收正畸治疗诱导的分子事件仍然未知。目前，对牙根吸收的唯一可用的诊断是通过X射线，并且当X射线可能检测到吸收时，该过程如果不是不可能的话，也是非常难以停止的。 本实验室建立了一种可重复的大鼠牙齿移动导致牙齿吸收的动物模型。在目前的R21申请中，我们申请资金来创建一个无牙根吸收的牙齿移动的动物模型，这将使我们能够区分表达以维持移动牙齿所需的骨吸收/沉积之间的平衡的基因，以及表达为这种平衡破坏的结果导致病理性牙根吸收的基因。这将通过使用DNA微阵列确定作为导致牙齿移动或牙根吸收的正畸力的应用的结果而表达的基因来实现。然后，我们将使用RT-PCR证实上述获得的数据，我们将阐明候选基因的空间和时间表达的根吸收。 更好地理解与这种病理过程中的大鼠动物模型的分子事件可能为我们提供了在人类的未来研究的起点，以促进治疗，预防和可能的早期诊断的风险，发展中国家的牙根吸收，由于正畸治疗的患者。

DESCRIPTION (provided by applicant): Root resorption, either physiological or pathological, results in the destruction of mineralized and non-mineralized tissues of the dental roots. Pathological root resorption, internal or external, can result from the presence of cysts, tumors, trauma, infections, periodontal disease or orthodontic treatment. This process could advance in time destroying the roots and resulting in tooth loss. Apical root resorption is one of the most common problems that orthodontists face during their practice. This process could compromise the benefits of otherwise a successful orthodontic treatment and could result in severe medico-legal ramifications. Although many clinical and histological studies have been carried out in order to elucidate the etiology and pathogenesis of external root resorption, the molecular events leading to root resorption induced by orthodontic treatment are still unknown. Currently, the only available diagnosis for root resorption is by X-rays and by the time the X-ray might detect the resorption, the process is very difficult, if not impossible, to stop. Our laboratory has established a reproducible rat animal model for tooth movement resulting in tooth resorption. In the present R21 application, we request funds to create an animal model for tooth movement without root resorption, that will allow us to differentiate between genes expressed to maintain the balance between bone resorption/apposition required to move teeth, and those expressed as consequence of disruption of this balance resulting in pathological root resorption. This will be accomplished by determining the genes expressed as result of the application of orthodontic forces resulting in either tooth movement or root resorption using DNA microarrays. We will then confirm the data obtained above using RT-PCR and we will elucidate the spatial and temporal expression of candidate genes for root resorption. A better comprehension of the molecular events associated with this pathological process in the rat animal model might provide us with the starting point for future studies in humans to facilitate the treatment, prevention and possible early diagnosis of patients at risk of developing root resorption due to orthodontic treatment.