تحليل القوى المستقرة لثلاثة انواع مختلفة من المواد الراتنجية بطريقة عملية وعددية == Static Stress Analysis For Three Different Types of Composite Materials Experimentally And Numerically

Author name: محمد وائل سعيد
Supervisor name: حكمت عبد الرحيم الغراوي
General topic: Dentistry
Specific topic: Dental Treatment
Degree: Master
University: Mustansiriyah University
Language: English
University location: Baghdad
First pages: 20T405 - p.pdf
Abstract: t is important to analyze and compare the stresses induced in different composite material types during load application to know which type of composite will behave as preferred under the loading in the same circumstances. This study aimed at measuring and comparing the stress induced in Filtek ™ Z350 XT (3M ESPE) composite, Tetric EvoCeram ® (ivoclar vivadent) composite and BRILLIANT ™ NG (Coltène/Whaledent) composite experimentally and numerically.Experimental analysis included cavity preparation in the Brass block with a concave (U - shape) cavity which represent a proximal cavity preparation. This cavity was used as a mold for sample preparation. The internal line and point angles of the cavity (mold) were rounded and the dimensions of the cavity (mold) were 10mm × 10mm × 10mm (Total height of the box × Width of the top side of box × Length of the top side of box). The internal diameter of “U” was 5 mm at the base of the box. The mold was used to prepare forty five samples, fifteen samples for each type of composite material. So, three groups were prepared : Group A filled with Filtek ™ Z350 XT composite material, Group B filled with Tetric EvoCeram ® composite material and Group C filled with BRILLIANT ™ NG composite material.Electrical strain gauge (Tokyo Sokki, Japan) was embedded in composite material horizontally at the same level in each sample. Static load of 50 N was applied perpendicular to the center of the occlusal surface of composite restoration in each sample testing. The strain gauge was connected to a Wheatstone bridge with a signal amplifier which measures the strain during load application and gives the amplified signal from (0 to 4.8 volt) to LabJack data acquisition where a stream software give the final values of strain with the aid of a scaled equation of voltage. Then, the von Mises stress (effective stress) was calculated by using equations. Numerical analysis was done by using ANSYS 16.1 - (2015) (finite element tool) software that was used to create the 3 - Dimensional models represented the same materials and dimensions used experimentally. The physical characteristics of the composite models were inserted in the software which included Elastic modulus and Poisson’s ratio (?). Analysis was selected in a finite element method according to boundary conditions. A mesh size and an element size were estimated during the study. The stresses were calculated at static load of 50 N with the ANSYS 16.1 - (2015) software.The data were analyzed statistically by One - way ANOVA test and Least Significant Difference (LSD) test. One - way ANOVA test and LSD test results showed that there was a highly significant difference (P<0.001) presented between groups A and B, groups A and C and between groups B and group C. The Stress induced in BRILLIANT ™ NG composite after load application was the lowest stress value followed by Tetric EvoCeram ® composite and followed by Filtek ™ Z350 XT composite which was the highest stress value experimentally and numerically.
Logo