Multiscale Modeling Of Enamel And Numerical Simulation Of Wear

After adulthood,people will not be regenerated after tooth destruction,and there are many forms of tooth destruction,including:wear,corrosion,and breakage.The most common form of damage to our teeth is wear,and the first place where the tooth wears is the surface of the tooth.The enamel is located on the surface of the crown of the tooth,so the most worn part of the structure of the tooth is enamel.Therefore,it is important to study the microstructure of enamel and the wear of enamel.The basic element of enamel is hexagonal hydroxyapatite crystal?HAP?.The HAP crystals are polymerized together to form mineral nanofibers;the nanofibers are longitudinally aligned to form fibers and thicker fibers;the fibers are then polymerized into rods.The head of the rod has a diameter of 5?m and a length of 7?m.The interrod is relatively thin and has a thickness of 800-1000 nm.The enamel rods are arranged to form rod bands,which are linear at a distance of 1/3 of the surface,while the remaining 2/3 of the rods are curved.The idea of this thesis is based on the finite element model including the geometric characteristics of fiber composites,the force analysis and wear calculation of the contact surface during wear,and the macroscopic analysis of enamel during sliding by changing the coordinates of surface element nodes.And the variation law of the wear coefficient of each component,and obtain the gradual characteristics of the wear morphology.The research arrangement of this paper is as follows:?1?According to the research basis of the predecessors,select the microscopic model of the experimental results,use the ANSYS software to establish the microscopic scale model of the enamel,and use HyperMesh to divide the finite element base mesh and model the enamel material parameters into the model to complete the modeling of the enamel micro-composite model.A representative surface element?RSE?of enamel was found by analyzing the ratio W₁?W of the amount of rods wear to the total wear in three directions?_x direction,?_y direction,45°direction).?2?Analyze the wear characteristics of the rods in a straight line and a curved shape by calculating the wear data.The effective wear rates of the two shapes of rods,interrods and enamel were discussed separately.The influence of the inclination angle of rods on the wear rate of linear rods and curved rods with different friction coefficients was analyzed.The effective wear rate^*of enamel was obtained by ANSYS.The influence of the ratio of the interrods wear coefficient and the rods wear coefficient ?₂/?₁ on the maximum and minimum values of^*is obtained by calculation.Using the stress cloud diagram drawn by ANSYS,the effects of different spherical indenter sliding directions on food destruction efficiency under different friction coefficients and different rods inclination angles are discussed.?3?After the calculated wear data is collated,the wear data of the linear rods and the curved rods are compared and analyzed,and their similarities and differences are obtained.