Dental Compression Analysis Using Confined Compression and Imagining

使用受限压缩和想象进行牙科压缩分析

• 批准号: 10416089
• 负责人: James L Drummond
• 金额: $ 31.92万
• 依托单位: JLDRUMMOND CONSULTING
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-06-01 至 2024-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10416089
• 关键词: Acids; Adherence; Adhesives; Aging; Artificial Saliva; Bacteria; Behavior; Bisphenol A-Glycidyl Methacrylate; Bite Force; Carbohydrates; Cells; Chemicals; Chemistry; Clinical; Computer software; Data; Dental; Dental caries; Dentin; Dentists; Development; Discipline; Environment; Environmental Microbiology; Enzymes; Esthetics; Event; Extracellular Matrix; Failure; Fracture; Gene Expression; Growth; High Pressure Liquid Chromatography; Image; Image Analysis; In Vitro; Inductively Coupled Plasma Mass Spectrometry; Investigation; Ions; Laboratories; Laser Microscopy; Liquid Chromatography; Literature; Manufacturer Name; Mastication; Materials Testing; Mechanics; Microbial Biofilms; Microbiology; Modeling; Oral; Oral Microbiology; Oral cavity; Organism; Periodicity; Photons; Play; Polymers; Predisposition; Production; Property; Radial; Reporting; Research; Reverse Transcriptase Polymerase Chain Reaction; Role; Science; Series; Source; Specimen; Stains; Statistical Data Interpretation; Streptococcus; Streptococcus mutans; Streptococcus sanguis; Stress; Surface; Testing; Three-Dimensional Image; Three-Dimensional Imaging; Time; Water; adhesive polymer; aged; aqueous; base; beamline; composite restoration; dental adhesive; dental biofilm; design; esterase; experimental study; geochemistry; image reconstruction; imaging capabilities; improved; in vivo; interfacial; multidisciplinary; nanoimaging; oral bacteria; oral biofilm; restoration; restorative composite; restorative material

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.

概括 我们的初步数据表明，在酯酶中老化修复性牙科复合材料 人工唾液（AS）中的酶导致直径强度相对于 含有或不含酸的陈水样本。在此数据的基础上，本研究将利用 含有复合样本的牙本质环，以保证牙本质粘合剂和结构的完整性 粘合复合材料界面经受模拟口腔环境的两种模型口腔 细菌（致龋性变形链球菌和血链球菌）并在酯酶存在下孵育 AS 培养基中的酶。此外，样本将受到轴向和径向循环 在牙本质粘合剂复合环内加载以模拟 I 类修复体。实验 与两种链球菌菌株一起使用将使我们能够确定是否致龋孵化 条件和/或生物膜生长以及葡萄糖酰转移酶（gtfB，一种关键酶）的表达 致龋生物膜中细胞外基质形成的产生）显着影响 测试样本的结构完整性。包含酯酶将使我们能够测试是否 这些酶会降解并降低牙本质-粘合剂-复合材料键的强度，因为我们 之前已经用复合材料展示过。静态测试将确定水的作用 地球化学条件（非生物或生物引起的）在攻击结构 测试样本的完整性和动态循环压缩将使我们能够确定 咀嚼模拟力对更真实地模拟体内压力的影响。 对从界面和本体复合材料中浸出的降解产物进行分析 通过电感耦合等离子体质谱 (ICP-MS) 进行定量表征 复合材料的无机成分（例如 Zr、Si 和 Ti），并通过液相色谱法/ 用于聚合物降解产物的串联 MS (LC-MS/MS)。微米和纳米成像分析 牙本质-粘合剂-复合材料体积（界面、孔隙和裂缝）应有助于澄清 导致牙科复合修复体临床失败的一系列事件。这是 预计细菌之间会观察到显着差异 相对于对照样本，在 AS 环境中与酯酶进行孵育 （未循环并在 AS 中老化 120 天）。牙科复合材料的行为似乎受到 迄今为止，文献中尚未报道这两种环境下的多轴载荷。 牙科复合材料在口腔中要经受极端的化学和机械条件 环境，这有助于材料在体内的降解和最终失效。