Characterisation techniques for enamel remineralisation: a comprehensive review

Enamel, the hardest and most mineralised tissue of the human body, serves as the outer barrier of teeth and protects them from mechanical and chemical damage. Its structural integrity relies on a delicate balance between demineralisation and remineralisation. Disruption of this equilibrium leads to dental caries, one of the most prevalent oral diseases worldwide. Remineralisation strategies, therefore, aim to restore mineral content and reinforce enamel resistance. Reliable characterisation of remineralisation is essential to assess treatment efficacy and guide the design of innovative biomaterials. This review provides a comprehensive overview of the methodologies available to evaluate enamel repair, encompassing surface morphology, mechanical performance, chemical composition and mineral density and crystallinity. For each category, the principles, advantages and limitations of the main techniques are critically discussed, with emphasis on their relevance to translational and clinical applications. By integrating insights from these complementary approaches, this work proposes a framework to select appropriate characterisation methods and highlights the importance of combining them to achieve a robust evaluation of enamel remineralisation. Such knowledge is key to advancing the development of novel materials and strategies for durable enamel restoration.