Dental Research Institute, Faculty of Dentistry, University of Toronto, ON, Canada.
J Dent Res. 2013 Nov;92(11):989-94. doi: 10.1177/0022034513504436. Epub 2013 Sep 11.
A major reason for dental resin composite restoration replacement is related to secondary caries promoted by acid production from bacteria including Streptococcus mutans (S. mutans). We hypothesized that S. mutans has esterase activities that degrade dental resin composites and adhesives. Standardized specimens of resin composite (Z250), total-etch (Scotchbond Multipurpose, SB), and self-etch (Easybond, EB) adhesives were incubated with S. mutans UA159 or uninoculated culture medium (control) for up to 30 days. Quantification of the BisGMA-derived biodegradation by-product, bishydroxy-propoxy-phenyl-propane (BisHPPP), was performed by high-performance liquid chromatography. Surface analysis of the specimens was performed by scanning electron microscopy (SEM). S. mutans was shown to have esterase activities in levels comparable with those found in human saliva. A trend of increasing BisHPPP release throughout the incubation period was observed for all materials and was more elevated in the presence of bacteria vs. control medium for EB and Z250, but not for SB (p < .05). SEM confirmed the increased degradation of all materials with S. mutans UA159 vs. control. S. mutans has esterase activities at levels that degrade resin composites and adhesives; degree of degradation was dependent on the material's chemical formulation. This finding suggests that the resin-dentin interface could be compromised by oral bacteria that contribute to the progression of secondary caries.
树脂基复合材料修复体更换的一个主要原因与细菌（包括变形链球菌）产酸引起的继发龋有关。我们假设变形链球菌具有酯酶活性，可以降解牙用树脂复合材料和粘结剂。将树脂复合材料（Z250）、全酸蚀（Scotchbond Multipurpose，SB）和自酸蚀（Easybond，EB）粘结剂的标准样本与变形链球菌 UA159 或未接种的培养基（对照）一起孵育，最多 30 天。通过高效液相色谱法对 BisGMA 衍生的生物降解副产物双羟丙氧基苯丙烷（BisHPPP）进行定量分析。通过扫描电子显微镜（SEM）对标本进行表面分析。变形链球菌具有与人类唾液中发现的酯酶活性相当的酯酶活性。观察到所有材料在整个孵育期内的 BisHPPP 释放量呈增加趋势，与对照培养基相比，在存在细菌的情况下 EB 和 Z250 的释放量更高，但 SB 则不然（p<0.05）。SEM 证实了所有材料与对照相比，与变形链球菌 UA159 共培养时的降解增加。变形链球菌具有可以降解树脂复合材料和粘结剂的酯酶活性；降解程度取决于材料的化学配方。这一发现表明，树脂-牙本质界面可能会被导致继发龋进展的口腔细菌破坏。
