Soft Denture Liner Adhesion to Conventional and CAD/CAM Processed Poly(Methyl Methacrylate) Acrylic Denture Resins-An In-Vitro Study

This study aimed to evaluate the airborne-particle abrasion surface treatment effects on the tensile bond strength (TBS) between resilient denture liner and CAD/CAM or conventional heat polymerized poly (methyl methacrylate) (PMMA) acrylic denture resins. A total of 48 dumbbell-shaped specimens (70 mm in total length, and 12 mm and 7 mm in diameter at the thickest and thinnest section, respectively) were prepared from CAD/CAM and conventional acrylic resins. Before relining with denture liner, 12 specimens from each material were surface-treated by 110 µm Al2O3 airborne-particle abrasion, and the remaining specimens served as control (no treatment). Following relining, all the specimens were aged by thermal cycling (1000 cycles, 5–55 °C). The TBS of denture liner to acrylic denture resins was tested in a universal testing apparatus at a 5 mm/min crosshead speed. The debonded surfaces were visually examined for the failure modes. ANOVA and multiple comparisons posthoc analysis tests were applied to determine the significant difference in TBS between the study groups (α = 0.05). A significant difference in TBS was observed between the control and surface treated groups (p < 0.001) for both acrylic resins materials. However, there was no statistically significant difference in bond strength between the acrylic resins materials (p = 0.739). Surface treatment with airborne-particle abrasion demonstrated increased TBS of the soft denture liners to acrylic resins. The TBS of conventional and CAD/CAM acrylic resins to soft denture liners were not considerably different.

Evaluation of Antimicrobial and Antibiofilm Activities of Copper Oxide Nanoparticles within Soft Denture Liners against Oral Pathogens

Objectives. Soft denture liners provide a favorable environment for adhesion and colonization of microorganisms. This in vitro study aimed to examine the efficacy of different concentrations of copper oxide nanoparticles (CuO NPs) incorporation into soft denture liner on the biofilm formation of the microbial species. Methods. Field Emission Scanning Electron Microscopy (FESEM) images from NPs were recorded. Antifungal susceptibility testing of CuO NPs against five standard strains of Candida albicans (CBS 10261, 1905, 1912, 1949, 2730), Streptococcus mutans (ATCC35668), Streptococcus sobrinus (ATCC27607), and Streptococcus salivarius (ATCC9222) was performed by the broth microdilution method with the Clinical and Laboratory Standards Institute reference method. The biofilm inhibition percentages of CuO NPs on the soft denture liners were determined by XTT assay. Results. The characterization of CuO NPs by scanning electron microscope (SEM) analyses confirmed the synthesis of NPs with appropriate structure and size with a mean diameter of 18.3 ± 9.1 nm. The CuO NPs successfully inhibited the growth of the tested standard strains of C. albicans and Streptococcus spp. at concentrations ranging from 64 to 128 µg mL−1. Indeed, incorporation of CuO NPs at a concentration of 500 µg mL−1 into the soft denture liners exhibited a significant activity (75%) in inhibition of C. albicans. biofilm formation in a dose-dependent manner. The biofilm formation of C. albicans in the presence of CuO NPs was lower than Streptococcus spp. in comparison with the control group ( p < 0.05 ). Conclusion. Incorporation of CuO NPs significantly decreased the colonization and plaque formation of the oral pathogens, especially C. albicans accumulation. These NPs may be useful as a promising agent for the antimicrobial management of soft denture liner materials.

Erratum to: Incorporation of Fluconazole and Ocimum Sanctum Oil in Soft Denture Liners to Treat Biofilms of Candida albicans Associated with Denture Stomatitis

Purpose: To investigate the In Vitro activity of incorporated antifungal agents like Fluconazole and Ocimum sanctum oil (Tulsi) in the denture soft liners to reduce the risks associated with the biofilms of Candida albicans.Materials and Methods: In the current study, the minimum inhibitory concentration (MIC) of two antifungal agents namely Fluconazole and O. sanctum (Tulsi oil) against C. albicans (ATCC 10231) was evaluated to examine their effect in reducing the count of candida and its biofilms. Analysis of physical properties such as surface roughness and hardness of soft denture liners (test and control) were also performed. The effect of both antifungal agents was also observed on cell morphology of candida cells using scanning electron microscopy (SEM).Results: Studies confirmed MIC value for fluconazole and O. sanctum oil as 600 and 400 µg/ml respectively. Surface hardness and roughness of soft denture material (test) remained unaltered. Finally, SEM studies also proved the effectiveness of incorporated antifungal agents on the cell morphology of C. albicans at their respective MIC values.Conclusions: This approach allows the prolonged drug release in the oral cavity which simultaneously treats the injured denture bearing tissues and also the infection, biofilms of candida without compromising on their physical properties. These studies are significant and have tremendous medicinal and therapeutic relevance. Keywords: Antifungal Agents; Biofilms; Candida; Scanning Electron Microscope; Soft Liners; Hardness; Surface Roughness; Minimal Inhibitory Concentration; Denture Stomatitis.

Incorporation of Fluconazole and Ocimum Sanctum Oil in Soft Denture Liners to Treat Biofilms of Candida albicans Associated with Denture Stomatitis

Purpose: To investigate the In Vitro activity of incorporated antifungal agents like Fluconazole and Ocimum sanctum oil (Tulsi) in the denture soft liners to reduce the risks associated with the biofilms of Candida albicans.Materials and Methods: In the current study, the minimum inhibitory concentration (MIC) of two antifungal agents namely Fluconazole and O. sanctum (Tulsi oil) against C. albicans (ATCC 10231) was evaluated to examine their effect in reducing the count of candida and its biofilms. Analysis of physical properties such as surface roughness and hardness of soft denture liners (test and control) were also performed. The effect of both antifungal agents was also observed on cell morphology of candida cells using scanning electron microscopy (SEM).Results: Studies confirmed MIC value for fluconazole and O. sanctum oil as 600 and 400 µg/ml respectively. Surface hardness and roughness of soft denture material (test) remained unaltered. Finally, SEM studies also proved the effectiveness of incorporated antifungal agents on the cell morphology of C. albicans at their respective MIC values.Conclusions: This approach allows the prolonged drug release in the oral cavity which simultaneously treats the injured denture bearing tissues and also the infection, biofilms of candida without compromising on their physical properties. These studies are significant and have tremendous medicinal and therapeutic relevance.