NANOSTRUCTURED BIOACTIVE MATERIALS

描述(申请人提供)：纳米级的羟基磷灰石、其他磷酸钙化合物以及其他生物活性无机材料将通过一种新开发的方法制备，该方法采用喷雾干燥或火焰热解技术，从而(1)可以获得广泛的目标颗粒尺寸，(2)可以制备低溶解度和高溶解度的化合物，(3)所制备的颗粒在形成后不会暴露在任何溶液环境中，因此将保持其原始的、高活性的表面(目标1)。由于其小尺寸和高反应活性，所制备的纳米材料有望在临床上有广泛的应用。其中两项将在目标2和目标3中进行评估。 目的评价纳米形态氟化钙(CaF2)作为氟化物(F)来源对牙釉质龋损再矿化的有效性，包括(1)体外模型以了解CaF_2颗粒大小与F沉积的关系；(2)体内唾液和菌斑模型以比较纳米CaF_2与当前使用的NaF含氟液产生的口腔氟滞留；(3)原位脱矿/再矿化模型以评价纳米CaF_2洗涤剂的再矿化效果。 目的3评价纳米磷酸钙和氟化钙在降低牙本质渗透性方面的效果，这是一种与牙齿过敏密切相关的特性。

DESCRIPTION (provided by applicant): Nano forms of hydroxyapatite, other calcium phosphate compounds, and additional bioactive inorganic materials will be prepared by a newly developed method, employing either a spray drying or a flame pyrolysis technique in such a way that (1) target particle sizes over a wide range can be obtained, (2) compounds with both low and high solubilities can be prepared, and (3) the prepared particles would not be exposed to any solution environment after their formation and therefore would retain their original, highly reactive surfaces (Aim 1). Due to their small sizes and high reactivity, the prepared nano materials are expected to have a range of clinical applications. Two of which will be evaluated in Aims 2 and 3. Aim 2 will focus on evaluating the effectiveness of nano forms calcium fluoride (CaF2) as the source of fluoride (F) for remineralizing tooth enamel carious lesions using (1) an in vitro model to understand the relationship between CaF2 particle size and F deposition, (2) an in vivo saliva and plaque model to compare oral F retention produced by the nano CaF2 and currently used NaF rinses, and (3) an in situ demineralization/remineralization model to evaluate the remineralization effects of the nano CaF2 rinse. Aim 3 will evaluate the effectiveness of nano sized calcium phosphates and calcium fluoride in reducing dentin permeability, a property closely associated with dental hypersensitivity.