Numerous methods have been investigated to manage dental caries, one of the top three diseases threatening human health as reported by the World Health Organization. An innovative strategy was proposed to prevent dental caries and achieve self-healing of the decayed tooth, and a novel bioactive peptide was designed and synthesized to construct an antibiofouling and mineralizing dual-bioactive tooth surface. Compared to its original endogenous peptide, the synthesized bioactive peptide showed statistically significantly higher binding affinity to the tooth surface, stronger suppression of demineralization, and a certain promotion of tooth remineralization. The abilities of the peptide to inhibit Streptococcus mutans (S. mutans) biofilm formation and S. mutans adhesion on the tooth surface were not affected after synthesis. Biocompatibility tests revealed the safety of the synthesized bioactive peptide. Interaction mechanisms between the synthesized bioactive peptide and tooth surface were also explained by molecular dynamic simulation analysis. In summary, the synthesized bioactive peptide could be applied safely to prevent dental caries and effectively induce in situ self-healing remineralization for treatment of the decayed tooth.

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Casein phosphate-amorphous calcium phosphate (CPP-ACP), as a remineralisation agent, is extensively used in managing demineralised enamel; however, its remineralisation kinetics is low. This study aimed to improve remineralisation kinetics of CPP-ACP by introducing a rapid remineralisation method with electrophoresis. In vitro, a pH-cycling enamel model was used to test remineralisation potentials of electrophoresis-aided CPP-ACP. For verifying remineralisation potentials of electrophoresis-aided CPP-ACP in vivo in a rabbit model, acid-etched enamel surface on rabbit maxillary incisors was remineralised by electrophoresis-aided CPP-ACP with 1.0 mA (group A) or 0.5 mA (group B). Both in vitro and in vivo, it was observed that electrophoresis was benefit to improve remineralisation kinetics of CPP-ACP, and the demineralised enamel was completely remineralised after 5 h. The Ca/P ratio in remineralised enamel consisted with that of hydroxyapatite, the microstructure in native enamel. Meanwhile, in vivo the micro-hardness of acid-etched enamel in group A (322.55 ± 31.90) and group B (322.55 ± 31.90) recovered up to the value of native enamel after 5 h remineralisation (p > 0.05). The Hematoxylin-eosin stain demonstrated that the electric field used in this study was safe on rabbit dental pulp. Therefore, this efficient and safe method has the potential to be applied in treating enamel deminerlisation.

Aim To assess the longitudinal association between adolescents’ and their mothers’ dental fear. Study Design A longitudinal questionnaire survey study. Methods A randomized sample of 12-year-old adolescents were selected from local Hong Kong schools. Adolescents and their mothers self-completed the Modified Dental Anxiety Scale (MDAS). The sociodemographic background of the mothers and the oral health habits of the adolescents were also collected and these measurements were repeated at 15- and 18-years-old. Non-parametric tests (Mann–Whitney U test/Kruskall Wallis test) were used to test associations between MDAS dental fear items and independent variables. Logistic regression (adjusted for family’s sociodemographic background and adolescent’s oral health habits) was performed to evaluate the longitudinal association between adolescents’ and mothers’ dental fear. Results A total of 212 mother-child pairs were recruited at baseline (12-year-old adolescents). In the first and second follow-ups (15- and 18-years-old), 195 and 182 mother-child pairs completed the survey. Significant associations between mother’s and child’s scores in “feeling about having their teeth scraped and polished”, “having teeth drilled”, and ‘having an injection in the gum’ were found when adolescents were 12- years-old (P < 0.01) and 18-years-old (P < 0.05), but not at 15-years-old. Conclusion Adolescents’ and mothers’ dental fear is associated at 12-years-old and 18-years-old, but not at 15-years-old, which is likely specific to the Hong Kong context but may be extrapolated to other industrialized countries with caution.

Conventional dental materials lack of the hierarchical architecture of enamel that exhibits excellent intrinsic-extrinsic mechanical properties. Moreover, restorative failures frequently occur due to physical and chemical mismatch between artificial materials and native dental hard tissue followed by recurrent caries which is caused by sugar-fermenting, acidogenic bacteria invasion of the defective cite. In order to resolve the limitations of the conventional dental materials, the aim of this study was to establish a non-cell-based biomimetic strategy to fabricate a novel bioactive material with enamel-like structure and antibacterial adhesion property. The evaporation-based, bottom-up and self-assembly method with layer-by-layer technique were used to form a large-area fluorapatite crystal layer containing antibacterial components. The multilayered structure was constructed by hydrothermal growth of the fluorapatite crystal layer and highly conformal adsorption to the crystal surface of a polyelectrolyte matrix film. Characterization and mechanical assessment demonstrated that the synthesized bioactive material resembled the native enamel in chemical components, mechanical properties and crystallographic structure. Antibacterial and cytocompatibility evaluation demonstrated that this material had the antibacterial adhesion property and biocompatibility. In combination with the molecular dynamics simulations to reveal the effects of variables on the crystallization mechanism, this study brings new prospects for the synthesis of enamel-inspired materials.

Various materials are used in bone tissue engineering (BTE). Graphene oxide (GO) is a good candidate for BTE due to its antibacterial activity and biocompatibility. In this study, an innovative biomaterial consists of GO, agarose and hydroxyapatite (HA) was synthesized using electrophoresis system. The characterization of the synthesized biomaterial showed that needle-like crystals with high purity were formed after 10 mA/10 h of electrophoresis treatment. Furthermore, the calcium-phosphate ratio was similar to thermodynamically stable HA. In the synthesized biomaterial with addition of 1.0 wt% of GO, the colony forming units test showed significantly less Staphylococcus aureus. Initial attachment of MC3T3-E1 cells on the synthesized biomaterial was observed which showed the safety of the synthesized biomaterial for cell viability. This study showed that the synthesized biomaterial is a promising material that can be used in BTE.

For covering the shortages of traditional treatments, a novel and non-invasive system was developed with the simple adaption of nature's own repair process, while an extrinsic electric field was introduced to improve its remineralization kinetics.

The distinct architecture of native enamel gives it its exquisite appearance and excellent intrinsic-extrinsic fracture toughening properties. However, damage to the enamel is irreversible. At present, the clinical treatment for enamel lesion is an invasive method; besides, its limitations, caused by the chemical and physical difference between restorative materials and dental hard tissue, makes the restorative effects far from ideal. With more investigations on the mechanism of amelogenesis, biomimetic mineralization techniques for enamel regeneration have been well developed, which hold great promise as a non-invasive strategy for enamel restoration. This review disclosed the chemical and physical mechanism of amelogenesis; meanwhile, it overviewed and summarized studies involving the regeneration of enamel microstructure in cell-free biomineralization approaches, which could bring new prospects for resolving the challenges in enamel regeneration.