DENTIN STRUCTURE, DEMINERALIZATION AND REMINERALIZATION

描述（由申请人提供）：目前微创牙科的趋势强调逆转和修复活动性蛀牙过程作为修复受损组织的第一步。牙釉质再矿化是一种公认的现象，并建立了机制。牙本质再矿化似乎是可能的，但由于其复杂的复合结构，是否可以通过牙本质再矿化恢复适当的力学功能尚未确定。新的方法现在允许定量研究本质牙本质再矿化的性质。我们试图定义与牙本质再矿化相关的结构和性质变化，以深入了解控制机制，并有助于定义再矿化组织的“质量”（水合弹性模量和硬度）。中心假设是，结合的，纤维内的矿物必须存在适当的机械功能。我们认为，如果残余的磷灰石晶体留在纤维间室中，为胶原原纤维内的再矿化过程提供核，这将是可能的。在目标1中。我们确定在pH = 5时，由致龋酸引起的纤束内矿物脱矿是否比纤束外矿物脱矿慢得多。目标2。确定牙本质龋齿的各个区域是否含有大量的纤维内矿物质，以及这是否与恒牙和乳牙管间牙本质的特性有关。目标3。评估经抗逆转录病毒治疗成功的龋齿，以确定它们是否已功能性再矿化，而Aim 4。评估功能性再矿化的策略：1)牙本质已被蛀牙酸去矿化；2)牙本质天然多区大面积蛀牙损伤。龋齿（蛀牙）的临床治疗越来越保守，强调危险因素的管理和微创修复。临床医生认为，在某些情况下，牙本质龋齿病变会再次变硬，但由于确切的情况尚不清楚，因此有理由保持谨慎。强调再矿化的新方法得到了临床试验的支持，但支持牙本质龋齿病变功能性再矿化的科学证据很薄弱。我们试图提供必要的基础，以确定功能性再矿化的条件。这将导致修复牙本质，恢复其机械特性的治疗方法，并减少手术修复干预的周期。

DESCRIPTION (provided by applicant): Current trends in minimally invasive dentistry emphasize the reversal and repair of the active caries process as a first step to restoring the damaged tissue. Enamel remineralization is an accepted phenomenon, and the mechanisms are established. Dentin remineralization appears to be possible, but due to its complex composite structure, it has not been established if proper mechanical function can be restored by remineralization of affected dentin. New methods now permit quantitative studies of the nature of dentin remineralization. We seek to define the structure and property changes associated with dentin remineralization to gain insight into the controlling mechanisms, and aid in defining the "quality" (hydrated elastic modulus and hardness) of the remineralized tissue. The central hypothesis is that bound, intrafibrillar mineral must be present for proper mechanical function. We contend that this will be possible if remnant apatite crystals remain in the intrafibrillar compartment to provide nuclei for the remineralization process within collagen fibrils. In Aim 1. we determine if much slower demineralization occurs for intrafibrillar mineral than for extrafibrillar mineral by cariogenic acids at pH = 5. Aim 2. determines if various zones of dentin caries contain substantial intrafibrillar mineral, and if this is associated with characteristic bulk properties of the intertubular dentin for permanent and primary teeth. Aim 3. evaluates carious teeth successfully treated by ART to determine if they have been functionally remineralized, while Aim 4. evaluates strategies for functionally remineralizing 1) dentin that has been demineralized by cariogenic acids and 2) multiple zones of large natural carious dentin lesions. Clinical treatment of caries (tooth decay) is increasingly more conservative and emphasizes management of risk factors and minimally invasive restoration. Clinicians believe that dentin caries lesions reharden under some circumstances, but are justifiably cautious since the exact conditions are unknown. New approaches emphasizing remineralization are supported by clinical trials showing effectiveness, yet the scientific evidence supporting functional remineralization efforts for dentin caries lesions is weak. We seek to provide the needed foundation that defines the conditions for functional remineralization. This will lead to therapies that will repair the dentin, restore its mechanical properties, and reduce the cycle of surgical-restorative interventions.