Alternative dental impression fillers made of nanorod glutinous rice flour particles through precipitation

Abstract

In this work, nanorod particles were synthesized from a locally available source, glutinous rice flour, using sodium hydroxide (NaOH) through a simple precipitation process. The synthesized nanofillers were then presented as an alternative organic filler for dental impression application to support the making of a diagnostic and working model. Dynamic Light Scattering, Scanning Electron Microscope, Fourier Transform Infrared Spectroscopy, x-ray Diffraction, Energy Dispersive Spectroscopy, Thermogravimetric Analysis, and Differential Scanning Colorimeter were used to characterize the fillers. The particle size measurement, morphology interaction, and composition of glutinous rice flour nanorod particles were also investigated. The cell viability using 3T3L1 cells was assessed to determine the safety of nanorod particles using the MTT assay and trypan blue solution. All treated samples exhibit a change in particle morphology from polyhedral to rod. Additionally, a decrease in crystallinity, dehydration, and gelatinization temperature was observed. The functional group interacting with sodium hydroxide also changes slightly after size reduction. The samples treated with 3000 centrifugation speed without surfactant addition showed changes from the control sample’s 3931.71 nm to the smallest average width particle size of 73.26 nm with an average length of 865.15 nm. All of the treated samples with NaOH and NaOH-surfactant additions met the non-cytotoxicity acceptance criteria in the range of 73.54%–99.58%, according to the cell viability results. The incorporation of 15 wt% of the synthesized nanorod fillers resulted in a 20 μm continuous line as the impression materials specimen, yielding a satisfactory detail reproduction test result. In conclusion, nanorod particles with biocompatible properties have been successfully manufactured and can potentially be used in the future as an alternative dental impression filler materials.