Section of Oral Health Promotion and Technology, Division of Oral Health, Technology and Epidemiology, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
Oral Care Research Laboratories, Research and Development Headquarters, Lion Corporation, Tokyo, Japan.
Oral Dis. 2018 Apr;24(3):465-475. doi: 10.1111/odi.12779. Epub 2017 Oct 18.
Sugar consumption has been decreasing in Japan, suggesting higher rates of sucrose-independent supragingival plaque formation. For developing an in vitro biofilm model of sucrose-independent supragingival plaque, this study aimed to investigate the compositions and functions on contributing to cariogenicity in comparison with sucrose-dependent biofilm.
An in vitro multispecies biofilm containing Actinomyces naeslundii, Streptococcus gordonii, S. mutans, Veillonella parvula and Fusobacterium nucleatum was formed on 24-well plates in the absence or presence of 1% sucrose. Compositions were assessed by plate culture, scanning electron microscopy and confocal laser scanning microscopy after fluorescent in situ hybridisation or labelling of extracellular polymeric substances (EPS). Functions were assessed by acidogenicity, adherence strength and sensitivities to anticaries agents.
Although both biofilms exhibited a Streptococcus predominant bacterial composition, there were differences in bacterial and EPS compositions; in particular, little glucan EPS was observed in sucrose-independent biofilm. Compared with sucrose-dependent biofilm, acidogenicity, adherence strength and antimicrobial resistance of sucrose-independent biofilm were only slightly lower. However, dextranase degradation was substantially lower in sucrose-independent biofilm.
Our findings suggest that sucrose-independent biofilm may have cariogenicity as with sucrose-dependent biofilm. These in vitro models can help further elucidate plaque-induced caries aetiology and develop new anticaries agents.
日本的糖摄入量一直在下降，这表明蔗糖非依赖性龈上菌斑的形成率更高。为了开发一种蔗糖非依赖性龈上菌斑的体外生物膜模型，本研究旨在比较与蔗糖依赖性生物膜相比，探讨其在致龋性方面的组成和功能。
在不存在或存在 1%蔗糖的情况下，将包含奈瑟放线菌、戈登链球菌、变形链球菌、小韦荣球菌和核梭杆菌的体外多菌种生物膜在 24 孔板上形成。通过平板培养、扫描电子显微镜和经荧光原位杂交或细胞外聚合物物质（EPS）标记后的共聚焦激光扫描显微镜评估组成。通过产酸、黏附强度和抗龋剂敏感性来评估功能。
尽管两种生物膜均表现出以链球菌为主的细菌组成，但在细菌和 EPS 组成上存在差异；特别是在蔗糖非依赖性生物膜中观察到很少的葡聚糖 EPS。与蔗糖依赖性生物膜相比，蔗糖非依赖性生物膜的产酸、黏附强度和抗菌药物耐药性仅略低。然而，蔗糖非依赖性生物膜中的葡聚糖酶降解显著降低。
我们的研究结果表明，蔗糖非依赖性生物膜可能具有与蔗糖依赖性生物膜相似的致龋性。这些体外模型有助于进一步阐明菌斑诱导的龋齿发病机制，并开发新的抗龋药物。
