Dental Compression Analysis Using Confined Compression and Imagining

摘要 我们的初步数据表明，在酯酶中老化修复牙科复合材料 人工唾液(AS)中的酶导致直径强度相对于 样品陈化水加或不加酸。在此数据的基础上，这项研究将利用 牙本质环内含复合试件，使牙本质的结构完整性与粘接剂 两种口腔模型模拟口腔环境下的粘接-复合材料界面 细菌(致龋变链球菌和血链球菌)及其在酯酶存在下的培养 以酵素为底物。此外，试件还将承受轴向和径向循环。 在这个牙本质-粘结剂-复合环内加载以模拟I类修复。实验 这两个链球菌菌株将使我们能够确定是否孵化成龋病 葡萄糖转移酶(GTFB)的生长和表达条件和/或生物膜 在致龋性生物膜中细胞外基质形成的产生)显著影响 测试样本的结构完整性。包括酯酶将使我们能够测试 这些酶会降解和降低牙本质-粘结剂-复合粘结剂的强度，因为我们 已经在以前的复合材料中展示过。静态测试将确定水的作用 地球化学条件(非生物或生物诱导的)在攻击构造中起作用。 测试样本的完整性和动态循环压缩将使我们能够确定 从咀嚼到更逼真地模拟体内应力的模拟力的影响。 从界面和散体复合材料中渗出的降解产物的分析将 电感耦合等离子体质谱(ICPMS)定量表征 复合材料的无机物成分(例如，锆、硅和钛)，并通过液相色谱/ 串联质谱仪(LC-MS/MS)用于聚合物降解产物。黄曲霉毒素的微纳成像分析 牙本质-粘接剂-复合体体积(界面、气孔和裂缝)应有助于澄清 导致牙科复合修复体临床失败的事件顺序。它是 预计在细菌之间和之间将观察到显著的差异 AS环境中的孵化与酯酶的比较 (非周期，AS中120d龄)。研究表明，牙科复合材料在不同载荷下的行为 到目前为止，在这两种环境下的多轴载荷还没有文献报道。 牙科复合材料在口腔中受到极端的化学和机械条件的影响。 环境，这有助于材料在体内的降解和最终失效。

SUMMARY Our preliminary data indicated that aging a restorative dental composite in an esterase enzyme in artificial saliva (AS) resulted in a significant decrease in diametral strength relative to specimens aged water with or without an acid. Building on this data, this research will utilize a dentin ring containing a composite specimen to the structural integrity of dentin-adhesive and adhesive-composite interfaces subjected to simulated oral environments with two model oral bacteria (cariogenic S. mutans and S. sanguinis) and incubation in the presence of esterase enzyme in AS media. In addition, the specimens will be subjected to axial and radial cyclic loading within this dentin-adhesive-composite ring to simulate a class I restoration. Experiments with the two Streptococcus strains will allow us to determine whether cariogenic incubation conditions and/or biofilm growth and expression of glucsoyltransferases (gtfB, a key enzyme in the production of extracellular matrix formation in cariogenic biofilms) significantly impact the structural integrity of the test specimens. Inclusion of esterases will allow us to test whether these enzymes degrade and reduce the strength of dentin-adhesive-composite bonds, as we have shown previously with composites. Static tests will determine the role aqueous geochemical conditions (either abiotic or biotically-induced) play in attacking the structural integrity of the test specimens, and dynamically cycled compression will allow us to determine the impact of simulated forces from mastication to more realistically model stress in vivo. Analysis of the degradation products leaching from the interfaces and bulk composite will be quantitatively characterized by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) for inorganic components of the composite (e.g. Zr, Si, and Ti), and by liquid chromatography/ tandem MS (LC-MS/MS) for polymer degradation products. Micro- and nano-imaging analysis of the dentin-adhesive-composite volumes (interfaces, pores, and cracks) should aid in clarification of the sequence of events leading to clinical failure of dental composite restorations. It is anticipated that significant differences will be observed between and among the bacteria incubations versus the esterase enzyme in AS environments with respect to control specimens (uncycled and aged 120 d in AS). It appears that behavior of dental composites subjected to multiaxial loading in these two environments has not been reported on in the literature to date. Dental composites are subjected to extreme chemical and mechanical conditions in the oral environment, which contribute to the degradation and ultimate failure of the material in vivo.