Antibacterial Properties and Biofilm Attachment of Contemporary Restorative Materials.

Objectives: To identify and compare contemporary restorative materials based on their antibacterial properties and potential to decrease biofilm attachment.
Methods: Thirty-seven discs were distributed into seven experimental groups: Filtek Supreme Ultra (FSU), SureFil SDR flow⁺ bulk-fill (SFF), Tetric Powerfil bulk-fill (TP), Activa Bioactive-Restorative (ACT); Surefil One (SO), Fuji IX, and Fuji II. Hydroxyapatite discs were used as control. The antimicrobial activity was tested using Disk Diffusion Assay. Streptococcus mutans (Sm) and Streptococcus gordonii (Sg) were grown in TSB at 37^oC in 5% CO₂/air to ~10⁸ colony forming units/ml (CFU). Trypticase Soy Agar (TSAII) plates were spread plated with each of the strains adjusted to McFarland standard 0.5. Discs were placed on the plates and incubated for 48 hours. Zones of inhibition around the discs were measured as bacterial inhibition. Assay was performed in duplicate. For the biofilm attachment assay, discs were immersed in saliva collected from 10 healthy subjects, then transferred to well-plates containing 10⁶ CFUs of Sm and Sg in TSB+1% sucrose and incubated. Discs with attached biofilm were transferred to microtubes containing 1ml of DiH2O and vortexed. The samples were spiral plated in TSAII for total counts and Mitis Salivarius Bacitracin (MSB) for mutans streptococci (MS) counts. Assay was performed in triplicate.
Results: Antimicrobial property was only observed around ACT against Sm. SFF, FSU, ACT, and Fuji II showed similar MS counts from biofilm, while SO, TP and Fuji IX showed lower MS values. TP showed a decrease in both total and MS bacterial counts. Fuji IX presented more total biofilm attachment but with increased MS counts. ACT showed an increase in both total and MS bacterial count. CFU counts are summarized in the table.
Conclusions: ACT was the only material with antibacterial properties. TP, Surefil One, and Fuji IX showed favorable potential to decrease biofilm attachment.