Attenuated Total Reflectance-Fourier Transform I nfrared (ATR-FTIR) Spectroscopy Coupled with Principal Component Analysis and Polymerase Chain Reaction (PCR) Assay for the Detection of Porcine and Bovine Gelatins in Dental Materials. tlsr. 2022;33(2):133–153. doi:10.21315/tlsr2022.33.2.7