Bioactive inorganic materials in dental resin infiltrants: a systematic and critical review of their effects on infiltrant properties and tooth surfaces.

OBJECTIVE: This review aimed to assess the effects of incorporating bioactive inorganic materials into resin infiltrants for the treatment of early enamel lesions and to investigate how these materials affect the properties of the enamel surface. METHODS: A structured search was conducted up to December 2024 using the Web of Science, Medline, Scopus, PubMed, Dimensions, and OpenAlex databases. Only in vitro studies, in which resin infiltrants were combined with bioactive materials, such as hydroxyapatite, bioactive glass, amorphous calcium phosphate, and tricalcium phosphate, were included. Studies were selected according to predefined eligibility criteria, and risk of bias was assessed using the RoBvis 2.0 tool. RESULTS: A total of 1054 articles were screened, 21 studies were assessed for full text, and 18 studies fulfilled the criteria. Bioactive glass (55.55%) and hydroxyapatite (55.55%) were the most commonly investigated additives, exhibiting favorable effects on remineralization and enamel surface properties (n = 13). Bioactive materials were incorporated into commercial ICON® (n = 6) and in experimental resin infiltrants (n = 12). The most frequently reported analyses were surface microhardness (n = 12), surface roughness (n = 8), degree of conversion (n = 8), and color stability (n = 6). Only three studies showed a low risk of bias, and 15 studies exhibited a moderate risk of bias. CONCLUSIONS: The literature revealed that researchers have considered the utilization of bioactive inorganic materials in resin infiltrants to treat white spot lesions. However, due to variations in methodology, materials, and testing conditions, comparisons across studies remain limited. CLINICAL RELEVANCE: Bioactive resin infiltrants exhibit therapeutic potential by penetrating and occluding microporosities in demineralized enamel, thereby arresting non-cavitated carious lesions, promoting remineralization, and inhibiting bacterial activity. Clinically, these functions may enhance long-term lesion control, reduce the need for restorative interventions, and facilitate a tissue-preserving approach in caries management.