APPLICATION OF THE DIGITAL IMAGE CORRELATION TECHNIQUE FOR INVESTIGATION OF DIFFERENT ALLCERAMIC SYSTEMS

Abstract

Mostly, mechanical properties such as elastic modulus, flexural strength and fracture toughness were assessed under static loading conditions for the initial characterization of materials. During this course authors presented the digital image correlation technique as possible method for biomechanical investigations of all-ceramics under vertical loading conditions using standard tensile testing machine and several samples of all-ceramics’ blocks: E-max lithium disilicate glass-ceramics, Vita enamic, Feldsphatic ceramic and Yttria-stabilized zirconia polycrystal ceramic. Lithium disilicate glass-ceramics has a needle like crystal structure that offers excellent strength and durability as well as outstanding optical properties. For the lithium disilicate ceramics, the amount of glass phase is determinant in their fatigue behavior. Vita enamic is the first hybrid dental ceramic with a dual-network structure. Feldsphatic is a glass material with an amorphous (non-crystalline) structure. Yttria-stabilized zirconia polycrystal is a high-strength ceramic with high values of flexular strength and fracture toughness. Zirconia, the strongest and toughest of all dental ceramics meets the mechanical requirements for high stress-bearing posterior restorations. All of these blocks were subjected to load in the tensile testing machine and the obtained strain was visualized using cameras and Aramis software. Findings provide that the highest strain was detected in Feldspathic, E-max and Zirconia all-ceramic blocks, respectively. Vita enamic was found to be the lowest strained due to polymer infiltrated its structure. This fact has significance for clinicians due to application of all’ceramic system in patients with decreased vertical occlusion and abrasion. Additionally, the hardness and elastic modulus of Vita enamic was found to be similar to those of the dental tissue values which makes this material a good choice for restoring posterior areas with inlays.