Impact of photodynamic therapy based on modified orthodontic self-cured acrylic resin containing titanium dioxide nanoparticles against Candida albicans.

BACKGROUND

This in vitro study was conducted to evaluate the impact of photodynamic therapy (PDT) using modified acrylic resin with titanium dioxide nanoparticles (TiO2NPs) on Candida albicans biofilm, physico-mechanical properties, and pro-inflammatory gene expression.

MATERIALS AND

METHODS

The biofilm inhibition test was used to assess the antimicrobial effectiveness against C. albicans biofilm. The levels of gene expression for TNF-α and IL-6 in human gingival fibroblast (HGF) cell line were examined using quantitative real-time polymerase chain reaction (qRT-PCR). The roughness, flexural strength, and microhardness of modified acrylic resin with different concentrations of TiO2NPs (0 %, 1 %, 2 %, and 3 %) were measured using a profilometer, a universal testing machine, and a digital hardness tester, respectively.

RESULTS

The C. albicans biofilm was most effectively reduced by 0.2 % chlorhexidine (CHX), showing the lowest colony count (5.94 ± 0.46 × 106 CFU/mL). Comparable results were observed with 3 % TiO2NPs-PDT (7.37 ± 1.34 × 106 CFU/mL, P = 0.300). The colony counts from 2 % TiO2NPs-PDT (9.21 ± 1.25 × 106 CFU/mL) was not significantly different from 3 % TiO2NPs-PDT (P = 0.529) but was notably higher than that of 0.2 % CHX (P = 0.004). The expression of TNF-α and IL-6 genes decreased significantly in HGF cell line when exposed to 2 % and 3 % TiO2NPs-PDT. Microhardness and flexural strength demonstrated a direct correlation with the concentration of TiO2NPs, while roughness showed an inverse correlation. Additionally, all groups exceeded the ISO standards for flexural strength.

CONCLUSION

3 % TiO2NPs-PDT reduced C. albicans biofilm and downregulated the pro-inflammatory gene expression without adversely affecting the properties of the acrylic resin, making it suitable for clinical use.