“…11 The use of natural test foods, such as oilseed, has been discontinued due to their high solubility during mastication, instability over time, and difficulty of homogenizing their fracture forces and deformation throughout their structures. 11 The Optosil ® (Heraeus Kulzer, Hanau, Germany) family of artificial (polydimethylsiloxane) test foods is considered to be suitable, 1,2,4,5,6,9,10,11,12,13,14,15 as it has produced results with validated correlations with other masticatory factors, such as the number of occlusal pairs and bite force. 3,4,5,6 However, few studies have properly evaluated the reproducibility of results obtained with Optosil ® products [Optosil ® 1980, 9,12 Optosil P Plus ® , 4 and Optosil Comfort ®13,14,15 (OC)].…”