IADR Abstract Archives
Bioactive Composites Prevent Secondary Caries: An In-vitro Biofilm Model.
Objectives: The biggest issue in achieving longevity of a resin-based composite (RBC) dental restoration is nowadays the onset of secondary caries (SC). This study aimed to evaluate the ability of bioactive RBCs to prevent SC formation using an in vitro model of cariogenic biofilm challenge.
Methods: Four sound bovine incisor teeth had their root removed and their pulp chamber filled, then sixteen circular class I cavities were obtained in the labial part of each incisor. Eight sound human molars had their root removed 3mm apical to cemento-enamel junction, and their pulp chamber filled. Four Class II cavities were made in each tooth having cervical margin in dentin. Cavities were filled with: two test bioactive RBCs, ACTIVA BioACTIVE-RESTORATIVE or PRESTO, a resin-modified glass ionomer cement (positive control, RMGIC, Ionolux), a conventional RBC (negative control, Filtek Supreme XTE). Each material filled one class II cavity and four class I cavities in each tooth, accordingly. Restorations were finished, specimens were sterilized and stored in artificial saliva for one week. Streptococcus mutans biofilm formation on the specimens’ surfaces was obtained using a continuous flow bioreactor (37 °C, 20 ml/h) and undefined mucin medium + 5 wt% sucrose for two weeks. Before and after microbiological procedures, specimens were scanned using microCT (Skyscan 1176, 9µm resolution, 80KV, 300mA); image reconstruction was performed using proprietary software.
Results: In both cavity types, conventional RBC and PRESTO showed SC development while RMGIC and ACTIVA expressed protection against SC and demineralization of surrounding enamel. In dentine, conventional RBC promoted SC development, RMGIC protected against demineralization, while bioactive RBCs did not promote SC nor protect against demineralization. ACTIVA showed gap formation after the incubation period.
Conclusions: ACTIVA is a promising bioactive material, able to prevent secondary caries and demineralization in vitro, similarly to the tested RMGIC.
Methods: Four sound bovine incisor teeth had their root removed and their pulp chamber filled, then sixteen circular class I cavities were obtained in the labial part of each incisor. Eight sound human molars had their root removed 3mm apical to cemento-enamel junction, and their pulp chamber filled. Four Class II cavities were made in each tooth having cervical margin in dentin. Cavities were filled with: two test bioactive RBCs, ACTIVA BioACTIVE-RESTORATIVE or PRESTO, a resin-modified glass ionomer cement (positive control, RMGIC, Ionolux), a conventional RBC (negative control, Filtek Supreme XTE). Each material filled one class II cavity and four class I cavities in each tooth, accordingly. Restorations were finished, specimens were sterilized and stored in artificial saliva for one week. Streptococcus mutans biofilm formation on the specimens’ surfaces was obtained using a continuous flow bioreactor (37 °C, 20 ml/h) and undefined mucin medium + 5 wt% sucrose for two weeks. Before and after microbiological procedures, specimens were scanned using microCT (Skyscan 1176, 9µm resolution, 80KV, 300mA); image reconstruction was performed using proprietary software.
Results: In both cavity types, conventional RBC and PRESTO showed SC development while RMGIC and ACTIVA expressed protection against SC and demineralization of surrounding enamel. In dentine, conventional RBC promoted SC development, RMGIC protected against demineralization, while bioactive RBCs did not promote SC nor protect against demineralization. ACTIVA showed gap formation after the incubation period.
Conclusions: ACTIVA is a promising bioactive material, able to prevent secondary caries and demineralization in vitro, similarly to the tested RMGIC.
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