Adherence of Streptococcus mutans on lithium disilicate porcelain specimens

• Published in: The Journal of prosthetic dentistry 2015-11, Vol.114 (5), p.696-701
• Main Authors: Vo, Diane T., DDS, Arola, Dwayne, PhD, Romberg, Elaine, PhD, Driscoll, Carl F., DMD, Jabra-Rizk, Mary Ann, PhD, Masri, Radi, DDS, MS, PhD
• Format: Article
• Language: English
• Subjects: Bacterial Adhesion; Colony Count, Microbial; Dental Materials; Dental Porcelain; Dentistry; Streptococcus mutans - isolation & purification; Streptococcus mutans - physiology; Surface Properties; Temperature
• ISSN: 0022-3913; 1097-6841
• DOI: 10.1016/j.prosdent.2015.06.017

Abstract Statement of problem Streptococcus mutans can adhere at restored tooth margins to cause recurrent caries. Limited information about surface quality and bacterial adherence is available for lithium disilicate ceramic materials. Purpose The purpose of this in vitro study was to investigate how bacterial adherence is influenced by commercially available preparations of lithium disilicate ceramic materials. Material and methods Seventeen rectangular specimens (10×10×4 mm) were fabricated for each type of lithium disilicate material: pressed (Press), milled (CAD), fluorapatite layered (ZirPress/Ceram), and glazed (Ceram Glaze). The surface roughness of each specimen was assessed before incubation with wild-type S mutans for 48 hours at 37°C with Brain Heart Infusion broth media under anaerobic conditions. Adherent bacteria were sonicated, diluted, and plated in triplicate for quantification using the plate count method to assay for colony forming units (CFUs) as an indication of bacterial viability. Statistical analysis was performed with SPSS using an analysis of variance (ANOVA) followed by the Tukey Honestly Significant Difference (HSD) test (α=.05). The Pearson r was used to evaluate the correlation between surface roughness and adherence. Results The surface roughness of Ceram Glaze (1.32 ±0.19 μm) was significantly the highest, followed by ZirPress/Ceram (0.71 ±0.09 μm), which was significantly rougher than the Press (0.11 ±0.02 μm) and CAD (0.10 ±0.02 μm) groups, which were not significantly different from each other. (F=513.898, P