Background: Dental caries remains a significant global health problem. One of the fundamental mechanisms underlying the development and progression of dental caries is the dynamic process of demineralisation/remineralisation. In vitro models have played a critical role in advancing our understanding of this process and identifying potential interventions to prevent or arrest dental caries. This literature review aims to provide a structured oversight of in vitro mineralisation models which have been used to study the tooth demineralisation/remineralisation process. Methods: Publications from 2019 to 2023 were screened to identify articles reporting the use of in vitro models to study the demineralisation/remineralisation of tooth caries. The included studies were methodologically assessed for their information on (i) substrate, (ii) lesion formation, and (iii) mineralisation models. Results: The most reported substrates used in the studies were human teeth along with bovine incisors. Acetic/lactic buffers were the most common solutions to induce caries lesions. pH cycling was the most frequently used mineralisation model for simulating the daily change within the oral environment. This review discussed the advantages and limitations of various approaches. Conclusions: Standardisation of in vitro mineralisation models is crucial for enabling effective comparison between studies and advancing caries research.

This study aimed to develop a Streptococcus mutans (S. mutans)-targeted peptide for caries management and evaluate its antibacterial efficacy. A novel peptide, GA-C16G2, was synthesised by attaching gallic acid (GA) onto an S. mutans-targeted antimicrobial peptide, C16G2. Peptide purity and stability were measured using high-performance liquid chromatography (HPLC). The secondary structure of GA-C16G2 was assessed using circular dichroism (CD) spectroscopy, and cytotoxicity was evaluated with the PrestoBlue assay. Antimicrobial activity against oral bacterial species was determined using minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays. Time-kill and biofilm inhibition assays further characterised the peptide's activity. Bacterial morphology and biofilm structure were analysed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). GA-C16G2 was synthesised with 95.02 % purity, and its secondary structure closely resembled that of the parent peptide C16G2. GA-C16G2 exhibited good stability in artificial saliva and showed low cytotoxicity towards human gingival fibroblasts. GA-C16G2 demonstrated potent antimicrobial activity against S. mutans (MIC: 3.1 μM, MBC: 20.8 μM) while showing weaker effects against commensal bacterial species. A time-kill assay confirmed the rapid bactericidal activity of GA-C16G2, reducing S. mutans viability by 97.22 % within one minute. GA-C16G2 also inhibited S. mutans biofilm formation. TEM and SEM images confirmed bacterial and biofilm disruption. This study demonstrates the successful development of a biocompatible and stable peptide, GA-C16G2, with rapid and potent selective in vitro antimicrobial activity against S. mutans. GA-C16G2 offers a novel therapeutic approach for targeted prevention and treatment of dental caries.

Glass ionomer cements (GICs) are considered one of the most suitable materials for restoring tooth cavities due to their unique bioactive properties. However, their inherently low mechanical strength limits their use as long-term or load-bearing restorations. Researchers have explored incorporating hydroxyapatite (HA) into GICs to enhance their strength and durability. This study aimed to review GICs modified by different forms of HA and their performance as a dental restorative material. A structured search strategy using the terms "glass ionomer cement" and "hydroxyapatite" was applied in PubMed, MEDLINE, and Embase to identify relevant studies published in English. A data-charting form was developed by two researchers to capture the key characteristics of eligible studies for inclusion. Extracted data covered HA forms, test methods, and main findings. The initial search identified 579 articles, and subsequently, 48 articles were included in the final review. The use of HA to modify GICs showed enhancement in mechanical, chemical, and biological properties, particularly in flexural strength and fluoride release. Compressive strength and diametral tensile strength outcomes were variable and influenced by HA proportion, size, morphology, and storage conditions. HA modification shows promise for reinforcing GICs and improving their bioactivity. However, heterogeneous findings highlight the need for standardized methodologies and clinical trials to validate long-term outcomes. This scoping review provides a valuable overview of HA modified-GICs research. Additionally, it identifies potential research areas that can be investigated further to enhance properties of HA modified-GICs for clinical application.