A wide variety of dental products that are launched on the market becomes the correct selection of these materials a difficult task. Although the physical and mechanical properties do not necessarily represent their actual clinical performance, they are used to guide the effects of changes in their composition or processing on these properties. Also, these tests might help somehow the clinician to choose once comparisons between former formulations and new ones, as well as, with the leading brand, are highlighted by manufactures. This book presents a review of the most important laboratory tests. In this manner, the knowledge of these tests will provide a critical opinion related to the properties of different dental materials.