Numerical study of the effect of dental implant inclination

© 2017, Journal of the Serbian Society for Computational Mechanics. This paper contains the results of a research focused on the determination of the influence of an implant inclination on the strain state throughout the acrylic block with implant. The aim of the presented research is to qualitatively determine the regions with the greatest strain fields on the models. The finite element models of implant and acrylic block are developed for predefined implant inclinations in order to analyze the influence of implant inclination on deformations on the outer surface of acrylic block. The comparative contour plots of stress and strain state of analyzed models, as well as the comparative diagrams with obtained results, are presented. The conclusions about the inclination angle which leads to the higher strains in the block-implant are explained. Obtained results could be applied for the planning of future experimental studies which could utilize this and similar models to determine their load transfer characteristics, and could be included in the planning of dental implant position, and prediction of successful dental therapy

Strain measurement of medical textile using 2d digital image correlation method

Medical textile plays an important role in the technical textiles sector as one of the most rapidly growing sectors in the technical textile market. The textile materials should have some adequate mechanical properties to be useful as medical textile. Tensile strength presents one of the basic mechanical properties used to describe textile specimens. Standardized tensile testing procedures on textile specimens were commonly used in the past. The aim of this paper was to measure in-plane strain field on the tensile medical textile specimen using 2D Digital Image Correlation method (2D-DIC). 2D-DIC is a non-contact optical method for accurate displacement and strain full-field measurement. In this study, two medical cotton textiles, with density 120 and 130 g/m2, were used to create three specimens for each material. Each specimen was placed in the tensile testing machine and measured until the break. During the tensile testing, camera was automatically recording full-field displacement in X and Y directions. Textile 1 and Textile 2 showed significant differences in point distance values, despite the small deviation in densities (less than 10%). Mean value of the elongation for Textile 1 is more than a double than the elongation for Textile 2, although the difference for mean value of Maximum force if negligible. Also, it has been showed that 2D-DIC can play significant role for measurement in textile mechanical properties measurement

Mechanical Properties of Direct and Indirect Composite Materials Used in Prosthodontics

This study was conducted to investigate composite materials using mechanical equipment corresponded to masticatory system composed of two antagonistic parts that simulates bimaxilar contact in occlusion and articulation. The aim of this study was to investigate restorative materials with different chemical properties and to find out which material showed the best mechanical properties. The experiment was conducted using 4 types × 20 specimens of direct resin composite materials and equal number of indirect resin composites (IRCs). The following composites were tested: Tetric (Ivoclar Vivadent), Kerr Herculite XRV (Kerr), Charisma (Heraeus Kulzer), Heliomolar (Ivoclar Vivadent), Artglass (Heraeus Kulzer), Targis/Vectris (Ivoclar Vivadent), Vita Zeta LC (Vita) and Kerr Herculite Lab (Kerr). The universal dimensions of all specimens were 5 mm × 5 mm with 2 mm thickness. This was achieved using silicone molds. A total of 160 specimens (80 direct composite specimens and 80 indirect composite specimens) were tested using tensile testing machine. Artglass showed minimal change in thickness (30.20 ± 23.0 μm) compared to others. The highest change in thickness was found in Heliomolar (86.2 ± 32.6 μm). In the group of direct composite materials, Tetric experienced the lowest thickness change (31.0 ± 8.8 μm), while Charisma showed thickness variation of 65.2 ± 27.3 μm. Among indirect composites, Vita Zeta LC showed the highest value of thickness variation (76.2 ± 31.3 μm). In this experimental study, indirect composite specimens showed superior mechanical performance compared to direct composite specimens highlighted Artglass as the material of choice viewed from mechanical aspect