AUTHOR=Yan Yanhong , Guan Yun , Luo Linjuan , Lu Bingqiang , Chen Feng , Jiang Beizhan 

TITLE=Effects of immunoglobulin Y-loaded amorphous calcium phosphate on dentinal tubules occlusion and antibacterial activity

JOURNAL=Frontiers in Bioengineering and Biotechnology

VOLUME=10

YEAR=2022

URL=https://www.frontiersin.org/journals/bioengineering-and-biotechnology/articles/10.3389/fbioe.2022.921336

DOI=10.3389/fbioe.2022.921336

ISSN=2296-4185

ABSTRACT=<p><bold>Aim:</bold> This study aimed to evaluate the effects of immunoglobulin Y (IgY)-loaded amorphous calcium phosphate (ACP) (IgY@ACP) on dentinal tubule occlusion and antibacterial activity.</p><p><bold>Methodology:</bold> IgY@ACP was synthesized based on a biomimetic mineralization strategy. The structure was examined by transmission electron microscopy and Fourier transform infrared spectroscopy. The IgY release property was assessed <italic>in vitro</italic>. The cell biocompatibility of IgY@ACP was evaluated by CCK-8. The dentin disks were prepared using healthy human molars, and their dentinal tubules were exposed to EDTA. Subsequently, they were randomly selected and treated with or without IgY@ACP for 7 days. The tubule occlusion morphologies and newly formed layers were observed by scanning electron microscopy (SEM) and x-ray diffraction, respectively. To evaluate the acid resistance and abrasion resistance of IgY@ACP, dentin disks that were treated for 1 day were immersed in acid solution or subjected to a toothbrush. The antibacterial effects against <italic>Streptococcus mutans</italic> (<italic>S. mutans</italic>) were evaluated by colony-forming unit (CFU) counting, adhesion property assessment, and crystal violet and live/dead bacterial staining. Finally, the occlusion effect was evaluated in rat incisors <italic>in vivo</italic>. One-way analysis of variance (ANOVA) was performed for statistical analysis. The level of significance was set at 0.05.</p><p><bold>Results:</bold> IgY@ACP presented an amorphous phase with a nanosize (60–80 nm) and sustained release of protein within 48 h. The CCK-8 results showed that IgY@ACP had good biocompatibility. After treatment with IgY@ACP for 1 day, the majority of dentinal tubules were occluded by a 0.3-μm-thick mineralized layer. Seven days later, all dentinal tubules were occluded by mineralization with a thickness of 1.4 μm and a depth of 16 μm. The newly mineralized layer showed hydroxyapatite-like diffraction peaks. In addition, IgY@ACP had good acid and abrasion resistance. After treatment with IgY@ACP, the CFU counting and adhesion rate of <italic>S. mutans</italic> were significantly reduced, the crystal violet staining was lighter, and the <italic>S. mutans</italic> staining revealed more dead cells. Most importantly, IgY@ACP had a certain occluding property in rat incisors <italic>in vivo</italic>.</p><p><bold>Conclusion:</bold> IgY@ACP can effectively occlude dentinal tubules with acid-resistant stability and has prominent anti-<italic>S. mutans</italic> effects, rendering it a potentially suitable desensitization material in the clinic.</p>