Methods for determining the bond strength between different materials and hard dental tissues

The strength of the adhesive bond is a critical determinant of the longevity of indirect restorations. Prior to the clinical introduction of new restorative materials and luting agents, it is essential to evaluate their bonding performance to hard dental tissues. This literature review aims to examine the various tests used to measure adhesive bond strength and to identify the factors that influence laboratory outcomes. Bond strength tests are classified as static or dynamic, and further subdivided into macro- and micro-tests according to the bonded surface area. Static methods include macro-shear, macro-tensile, macro-push-out, micro-shear, micro-tensile, and micro-push-out tests. Dynamic methods comprise macro- and micro-shear, macro- and micro-tensile tests, three- and four-point micro-bending techniques, and micro-rotation tests. Factors affecting test results are associated with the substrate, the sample characteristics, and the test protocol itself. Laboratory methods for assessing adhesive bond strength are highly valuable for clinicians, as they support informed selection of restorative materials, adhesive systems, and cementing agents. When choosing an appropriate testing method, researchers must consider the specific properties of the hard dental tissues, restorative materials, and cements under investigation.