Antimicrobial and protective effects of non-thermal plasma treatments on the performance of a resinous liner

Antimicrobial surface processing of polymethyl methacrylate denture base resin using a novel silica-based coating technology

OBJECTIVES

This study investigated the surface characteristics of denture base resin coatings prepared using a novel silica-based film containing hinokitiol and assessed the effect of this coating on Candida albicans adhesion and growth.

METHODS

Silica-based coating solutions (control solution; CS) and CS containing hinokitiol (CS-H) were prepared. C. albicans biofilm formed on denture base specimens coated with each solution and these uncoated specimens (control) were analyzed using colony-forming unit (CFU) assay, fluorescence microscopy, and scanning electron microscopy (SEM). Specimen surfaces were analyzed by measuring the surface roughness and wettability and with Fourier-transform infrared (FT-IR) and proton nuclear magnetic resonance (¹H NMR). Stability of coated specimens was assessed via immersion in water for 1 week for each group (control-1w, CS-1w, and CS-H-1w) followed by CFU assay, measurement of surface roughness and wettability, and FT-IR.

RESULTS

CS-H and CS-H-1w contained significantly lower CFUs than those present in the control and control-1w, which was also confirmed via SEM. Fluorescence microscopy from the CS-H group identified several dead cells. The values of surface roughness from coating groups were significantly less than those from the control and control-1w. The surface wettability from all coating groups exhibited high hydrophobicity. FT-IR analyses demonstrated that specimens were successfully coated, and ¹H NMR analyses showed that hinokitiol was incorporated inside CS-H.

CONCLUSIONS

A silica-based denture coating that incorporates hinokitiol inhibits C. albicans growth on denture.

CLINICAL RELEVANCE

We provide a novel antifungal denture coating which can be helpful for the treatment of denture stomatitis.

Mechanical properties, corrosion resistance, and anti-adherence characterization of pure titanium fabricated by casting, milling, and selective laser melting

Milling and selective laser melting (SLM) technology have become new options for removable partial denture (RPD) processing. However, whether milling and SLM technology has an impact on the properties of RPD remains unclear, which is also the aim of our study. To investigate the effects of milling and SLM technology on pure titanium, mechanical property, corrosion resistance, and anti-adherence of specimens were evaluated, and specimens processed by lost-wax casting were used as control. Compared with casting and milling groups, the SLM group showed enhanced Vickers hardness (402.1 ± 13.0 HV), tensile stress (694.4 ± 4.5 MPa), and larger electrochemical capacitance arc radius compared with casting and milling groups. A series of adhesion-related genes (Als1, Als3, and HWP1) of Candida albicans cultured on SLM specimens were upregulated for more than two times that of casting and milling groups. However, images from scanning electron microscopy and confocal laser scanning microscopy exhibited similar biofilm morphology and biomass of C. albicans on a titanium disk processed by casting, milling, and SLM. Dwindled water contact angle (64.7 ± 0.6°) and higher TiO₂ constituents (40.82%) in the SLM group might lead to the incompatibility of genetic expression and biofilm generation. Our findings indicated that SLM is an ideal process to produce titanium dentures, providing a reference on the selection of processing technology for dentists.

Effect of sealer coating on hardness and water sorption data of soft denture lining materials

Soft denture lining (SDL) are acrylic or silicone based materials that can be cured with heat or auto polymerization process, which is commonly used in removable prosthodontics to reline the intaglio (interior) surface of the denture. Loss of softness due to aging process is caused by loss of plasticizer and other soluble component. However, water sorption causes changes in structure and increased materials hardness, thus need frequent replacement of the materials. To extend the durability of the SDL, sealer coating (SC) was used. In this data, sealant coating acts as mechanical barrier to prevent water sorption and solubility of the chemical component to preserved material hardness. This article provides the data of sealant coating effect on hardness and water sorption of acrylic-based and silicone-based SDL materials was arranged in 4 test group: pristine and coated acrylic SDL and pristine silicone SDL and coated silicone SDL. Shore Hardness test was carried out using a Shore A Durometer and water sorption data were presented. Accordingly, the data was statistically analyzed for comparison using independent T-test for shore A hardness and water sorption.