Influence of Curing Time on the Microbiological Behavior of Bulk-Fill Nanohybrid Resin Composites

Polymers

Lorenzo Breschi¹  Nicoleta Ilie²  Milena Cadenaro³  Allegra Comba⁴  Nicola Scotti⁴  Andrei C. Ionescu⁵  Eugenio Brambilla⁵ 

[1] Department of Biomedical and Neuromotor Sciences, DIBINEM, University of Bologna, Alma Mater Studiorum, Via San Vitale 59, 40125 Bologna, Italy;Department of Conservative Dentistry and Periodontology, University Hospital, Ludwig-Maximilians-University, Goethestr. 70, 80336 Munich, Germany;Department of Medical Sciences, University of Trieste, 34125 Trieste, Italy;Department of Surgical Sciences, University of Turin, via Nizza, 230, 10126 Torino, Italy;Oral Microbiology and Biomaterials Laboratory, Department of Biomedical, Surgical and Dental Sciences, Università degli Studi di Milano, via Pascal, 36, 20133 Milano, Italy;

关键词: bulk fill;    composite resin;    restorative materials;    surface characterization;    energy-dispersive X-ray spectroscopy;    scanning electron microscopy;   

DOI  :  10.3390/polym13172948

来源: DOAJ

【 摘 要 】

This in vitro study aimed to evaluate the influence of curing time on surface characteristics and microbiological behavior of three bulk-fill resin-based composites (RBCs). Materials were light-cured for either 10 s or 80 s, then finished using a standard clinical procedure. They were characterized by surface morphology (SEM), surface elemental composition (EDS), surface roughness (SR), and surface free energy (SFE). Microbiological behavior was assessed as S. mutans adherence (2 h) and biofilm formation (24 h) using a continuous-flow bioreactor. Statistical analysis included a two-way ANOVA and Tukey’s test (p < 0.05). Materials differed substantially as filler shape, dimension, elemental composition and resin matrix composition. Significant differences between materials were found for SR, SFE, and microbiological behavior. Such differences were less pronounced or disappeared after prolonged photocuring. The latter yielded significantly lower adherence and biofilm formation on all tested materials, similar to conventional RBCs. Improved photoinitiators and UDMA-based resin matrix composition may explain these results. No correlation between surface characteristics and microbiological behavior can explain the similar microbiological behavior of bulk-fill materials after prolonged photocuring. This different performance of bulk-fill materials compared with conventional RBCs, where surface characteristics, especially surface chemistry, influence microbiological behavior, may have important implications for secondary caries occurrence and restoration longevity.

【 授权许可】

Unknown