Objectives

Microleakage is a determinant factor of failures in sealant application. In this study, DMAEM (dodecylmethylaminoethyl methacrylate), a pH-responsive antibacterial agent, was incorporated into resin-based sealant for the first time. The objectives of this study were to: (1) investigate the long-term performance of DMAEM-modified sealants against oral microbial-aging; and (2) investigate the long-term preventive effect of DMAEM-modified sealants on microleakage.

Methods

Depth-of-cure and cytotoxicity of DMAEM-modified sealants were measured. Then, an aging model using biofilm derived from the saliva of high caries experience children was conducted. After aging, microhardness and surface roughness were measured. Biofilm activity, lactic acid production and exopolysaccharide (EPS) production were measured. 16S rRNA gene sequencing were also performed. The effects of DMAEM on microleakage were tested using an in vitro microleakage assessment.

Results

The addition of DMAEM with a mass fraction of 2.5–10% did not affect depth-of-cure values and cytotoxicity of sealants. Adding 2.5–10% DMAEM did not affect the surface roughness and microhardness after aging. Compared to control, adding 2.5–10% DMAEM reduced biofilm metabolic activity by more than 80%. The lactic acid production and EPS production were reduced by 50% in DMAEM groups. DMAEM-modified sealants maintained the microbial diversity of biofilm after aging, they also inhibited the growth of lactobacillus. The 5% and 10% DMAEM groups exhibited a significant reduction in microleakage compared to control.

Significance

The long-term antibacterial activities against oral microbial-aging and the long-term microecosystem-regulating capabilities enabled DMAEM-modified sealant to prevent microleakage in sealant application and thus prevent dental caries.

中文翻译：

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智能 pH 响应牙科密封剂可防止长期微渗漏

目标

微泄漏是密封剂应用失败的决定性因素。在这项研究中，DMAEM（甲基丙烯酸十二烷基甲氨基乙酯）是一种 pH 响应性抗菌剂，首次被加入到树脂基密封胶中。本研究的目的是：(1) 研究 DMAEM 改性密封剂对口腔微生物老化的长期性能；(2) 研究 DMAEM 改性密封剂对微渗漏的长期预防效果。

方法

测量了 DMAEM 改性密封剂的固化深度和细胞毒性。然后，使用源自高龋儿童唾液的生物膜进行老化模型。时效后，测量显微硬度和表面粗糙度。测量了生物膜活性、乳酸产量和胞外多糖 (EPS) 产量。还进行了 16S rRNA 基因测序。DMAEM 对微渗漏的影响通过体外微渗漏评估进行了测试。

结果

添加质量分数为 2.5-10% 的 DMAEM 不会影响密封剂的固化深度值和细胞毒性。添加 2.5-10% DMAEM 不会影响时效后的表面粗糙度和显微硬度。与对照相比，添加 2.5-10% DMAEM 将生物膜代谢活性降低了 80% 以上。DMAEM 组的乳酸产量和 EPS 产量降低了 50%。DMAEM改性密封胶在老化后保持了生物膜的微生物多样性，同时也抑制了乳酸菌的生长。与对照组相比，5% 和 10% DMAEM 组的微渗漏显着减少。

意义

对口腔微生物老化的长期抗菌活性和长期微生态调节能力使 DMAEM 改性密封剂能够防止密封剂应用中的微渗漏，从而防止龋齿。