DOI: 10.25442/hku.31037032
title: Supporting data for "Development of a novel copper tetraamine fluoride for caries management"

description: Copper is a widely used metal for its antibacterial properties. Copper materials inhibit the growth of cariogenic bacteria while maintaining low toxicity towards human cells. Moreover, copper compounds are easily available and extensively accessible for manufacturing. Considering their antimicrobial properties, simplicity, and affordability, the use of copper is a rational approach to developing a novel anti-caries agent. This thesis begins with a bibliometric analysis to examine research interest in copper materials for caries management. Since the first publication in 1980, the number of studies has gradually increased, with two-thirds of the publications released in the last five years, starting from 2018. This trend highlights a growing interest in copper materials for caries management. Subsequently, a scoping review was conducted to comprehensively assess the types, properties, and potential applications of copper materials in this context. The review identified 34 publications, categorising copper materials into copper and copper alloy materials, copper salt materials, and copper oxide materials. These materials exhibit antimicrobial effects that inhibit cariogenic bacteria and <i>Candida albicans</i>. Scientists incorporated copper materials into dental materials and even drinking water and sugar for caries prevention. The thesis includes four laboratory studies aimed at developing a novel anti-caries agent using copper, ammonia and fluoride. Ammonia is known for its antibacterial properties. It also provides an alkaline environment that prevents the demineralisation of hydroxyapatite in acidic conditions. Furthermore, ammonia acts as a stronger field ligand than water. Metal ammine complexes exhibit greater stability and reduced oxidation compared to their aquo counterparts. Fluoride is a potent remineralising agent in caries management. It can replace hydroxyl groups to form fluorapatite which is more resistant to acid dissolution than hydroxyapatite. The first study focused on developing a novel and biocompatible copper tetraamine fluoride using copper fluoride and ammonia solution. The resulting alkaline 58% copper tetraamine fluoride solution demonstrated biocompatibility, antibacterial properties, and non-discolouring characteristics. The second study investigated the antimicrobial effects of copper tetraamine fluoride against common microbes associated with dental caries and periodontal disease, including <i>Streptococcus mutans</i>, <i>Streptococcus sobrinus</i>, <i>Lactobacillus acidophilus</i>, <i>Lacticaseibacillus casei</i>, <i>Actinomyces naeslundii</i>, <i>Candida albicans</i>, <i>Enterococcus faecalis</i>, <i>Porphyromonas gingivalis</i> and <i>Actinobacillus actinomycetemcomitans</i>. Results indicated that copper tetraamine fluoride exhibits antimicrobial activity against these microbes, suggesting its potential use in managing dental caries and periodontal disease. The third study examined the antibacterial, mineralising, and discolouring properties of copper tetraamine fluoride on artificial dentine caries. Results demonstrated that copper tetraamine fluoride inhibited <i>Streptococcus mutans</i> and remineralised artificial dentine caries without causing discolouration. The final study evaluated the effects of copper tetraamine fluoride on artificial enamel caries. Results showed that copper tetraamine fluoride inhibited <i>Streptococcus mutans</i> biofilm and remineralised artificial enamel caries without discolouration. In conclusion, the development of biocompatible, antibacterial, and non-discolouring copper tetraamine fluoride with remineralising properties has been achieved. Copper tetraamine fluoride effectively arrests the demineralisation of both enamel and dentine. If copper tetraamine fluoride is successfully translated into clinical application, it can serve as a simple and affordable anti-caries agent for clinicians to prevent dental caries.