The International Organization for Standardization (ISO) has adopted Ultradent Products Inc’s notched-edge shear bond strength testing method as a new standard. After conducting a study involving more than 20 independent organizations, ISO determined the notched-edge method superior to other shear bond strength testing methods previously available.
ISO Standard 29022 specifies a shear test method used to determine the adhesive bond strength between direct dental restorative materials and tooth structure, such as dentin or enamel. The method is principally intended for adhesives and includes substrate selection, storage, and handling of tooth structure, as well as the procedure for testing. A key element within the testing is a notched-edge crosshead used to shear the bonded specimen with an even distribution of force. Testing results are more accurate with a notched contact because they will closely approximate adhesive shear strength, rather than peel strength produced by using a straight contact.
The ISO develops and publishes international standards to ensure that products and services are safe, high quality, and reliable. ISO protocol is employed by many organizations worldwide such as the Food and Drug Administration (FDA), which often grants approval only to products that pass ISO’s meticulous testing standards.