Department of Prosthetic Dentistry, Regensburg University Medical Center, Regensburg, Germany.
Acta Odontol Scand. 2012 Mar;70(2):114-21. doi: 10.3109/00016357.2011.600703. Epub 2011 Jul 25.
To examine potential correlations between streptococcal biofilm formation and lactate production in streptococcal biofilms formed on the surface of dental materials with different surface characteristics.
Samples of a glass-ionomer cement (Ketac Molar) and a ceramic (Empress 2) were incubated with whole saliva and suspensions of Streptococcus mutans ATCC 25175 or Streptococcus sobrinus ATCC 33478 for initiating single-species biofilm formation for either 4 or 24 h. The relative amount of adherent, viable cells was determined using a Resazurin and a MTT assay. Metabolic activity was assessed by quantifying lactate production with a modification of the commercial Clinpro Cario L-Pop kit.
Both assays identified similar S. sobrinus biofilm formation on the two substrata; for S. mutans, the MTT test showed significantly fewer streptococci on the glass-ionomer cement than on the ceramic. Concerning metabolic activity, for S. sobrinus, significantly higher lactate production was observed for biofilms formed on the glass-ionomer cement in comparison to the ceramic, whereas similar values were identified for S. mutans.
Within the limitations of the study, the results suggest that the pure amount of adherent streptococci does not a priori indicate the metabolic activity of the cariogenic bacteria organized in the respective biofilm. Thus, comparisons between the relative amount of adherent streptococci and their metabolic activity may allow for an improved understanding of the effect of dental material surfaces on the formation and metabolic activity of streptococcal biofilms.
研究不同表面特性的牙科材料表面形成的链球菌生物膜中链球菌生物膜形成与乳酸产生之间的潜在相关性。
将玻璃离子水门汀（Ketac Molar）和陶瓷（Empress 2）样品与全唾液和变异链球菌 ATCC 25175 或远缘链球菌 ATCC 33478 的悬浮液孵育，以启动单一物种生物膜形成，孵育时间分别为 4 小时或 24 小时。使用 Resazurin 和 MTT 测定法测定附着的活细胞的相对量。通过对商业 Clinpro Cario L-Pop 试剂盒的修改来定量乳酸产生来评估代谢活性。
两种检测方法均在两种基质上鉴定出相似的远缘链球菌生物膜形成；对于变异链球菌，MTT 试验显示在玻璃离子水门汀上的链球菌明显少于陶瓷上的链球菌。关于代谢活性，对于远缘链球菌，在玻璃离子水门汀上形成的生物膜的乳酸产生明显高于陶瓷上的生物膜，而变异链球菌的乳酸产生则相似。
在研究的限制范围内，结果表明，附着的链球菌的纯量不一定预先指示在各自生物膜中组织的致龋细菌的代谢活性。因此，附着的链球菌的相对量与其代谢活性之间的比较可以更好地理解牙科材料表面对链球菌生物膜形成和代谢活性的影响。
