Contemporary biomimetic and bioactive materials in paediatric dentistry: a narrative review

Biomimetic dentistry seeks to restore the structure and function of natural tooth tissues using materials that closely approximate their biological counterparts. Despite the growing clinical adoption of materials marketed as "biomimetic" or "bioactive," a persistent terminological ambiguity between these two terms has complicated evidence synthesis and clinical decision-making, particularly in the paediatric context. This narrative review, in which no systematic risk-of-bias assessment was performed, proposes a conceptual two-tier classification framework for biomimetic dental materials, distinguishing passive biomimetics, which replicate physical tooth tissue properties without inducing a biological response, from bioactive substances, which actively promote healing or remineralisation. Passive biomimetics encompass dental ceramics and resin-based composites. Bioactive substances are further subdivided into ion-releasing materials, bioceramic-based substances, biomolecular/bioinductive systems, and smart adhesive/hybrid systems. Each category is appraised against the FDI 2022 Policy Statement criteria for bioactive restorative materials. The proposed classification has not been prospectively validated and is intended as a conceptual framework to guide clinical reasoning and future research. Evidence quality varies considerably across categories: while materials such as glass ionomer cements and mineral trioxide aggregate are supported by extensive clinical data, emerging approaches including self-assembling peptide P11-4 and bioactive adhesive systems remain primarily supported by in vitro or short-term evidence. Future research should prioritise long-term randomised controlled trials in paediatric populations to validate the clinical relevance of emerging biomimetic strategies.