OBJECTIVE: The objective of this study is to determine the effect of interfacial reflection correction (IRC) on the accuracy of this reflectance model for contemporary dental resin composite materials. METHODS: Visible reflectance spectra were obtained for varying thicknesses (∼0.3-1.2mm) of five shades of each of two brands (Herculite Ultra and Kalore) of dental resin composite materials on black, gray and white backings. For each shade and brand, K-M theory was fit (SAS non-linear fit) for each of three IRC methods: (1) no IRC (No), (2) an IRC method which uses a theoretical value of the internal reflection for translucent materials (Tr), and (3) an IRC method which uses a derived value of the internal reflection for opaque materials (Op). The errors were subjected to repeated measures analysis of variance and Bonferroni corrections were applied to selected pairwise comparisons. RESULTS: The Op method had a statistically lower error than the No method at wavelengths from 460 to 560nm, and the Tr method had this lower error at wavelengths from 440 to 780nm. SIGNIFICANCE: Corrected K-M reflectance theory may be used to accurately quantify the optical K-M absorption and scattering coefficients for contemporary dental resin composite materials, and this theory may be used to calculate accurately the reflectance spectrum for a clinically relevant thickness value and for a backing that is low, mid-range or high in lightness. Both color and translucency information of resin composite materials may be accurately predicted using corrected Kubelka-Munk reflectance model.
OBJECTIVE: The objective of this study is to determine the effect of interfacial reflection correction (IRC) on the accuracy of this reflectance model for contemporary dental resin composite materials. METHODS: Visible reflectance spectra were obtained for varying thicknesses (∼0.3-1.2mm) of five shades of each of two brands (Herculite Ultra and Kalore) of dental resin composite materials on black, gray and white backings. For each shade and brand, K-M theory was fit (SAS non-linear fit) for each of three IRC methods: (1) no IRC (No), (2) an IRC method which uses a theoretical value of the internal reflection for translucent materials (Tr), and (3) an IRC method which uses a derived value of the internal reflection for opaque materials (Op). The errors were subjected to repeated measures analysis of variance and Bonferroni corrections were applied to selected pairwise comparisons. RESULTS: The Op method had a statistically lower error than the No method at wavelengths from 460 to 560nm, and the Tr method had this lower error at wavelengths from 440 to 780nm. SIGNIFICANCE: Corrected K-M reflectance theory may be used to accurately quantify the optical K-M absorption and scattering coefficients for contemporary dental resin composite materials, and this theory may be used to calculate accurately the reflectance spectrum for a clinically relevant thickness value and for a backing that is low, mid-range or high in lightness. Both color and translucency information of resin composite materials may be accurately predicted using corrected Kubelka-Munk reflectance model.
Authors: Alvin G Wee; Damian A Winkelmann; David J Gozalo; Masayasu Ito; William M Johnston Journal: J Prosthet Dent Date: 2022-02-17 Impact factor: 4.148
Authors: Milagros Adobes-Martín; Natividad Alcón; María Victoria López-Mollá; Javier Gámez-Payá; Estibaliz López-Fernández Journal: Int J Environ Res Public Health Date: 2022-04-13 Impact factor: 4.614