Influence of Preparation Design, Restorative Material and Load Direction on The Stress Distribution of Ceramic Veneer in Upper Central Incisor

Abstract

Objective: Evaluate the effect of four preparation designs, two ceramic materials, and two occlusion contact types on the stress distribution of ceramic veneer in upper central incisor. Material and methods: 3D-models were performed in the modeling software containing enamel, dentin, pulp, periodontal ligament and a base of polyurethane resin. The designs were modeled and exported to the computer aided engineering software to perform the static structural analysis. For the mesh, a total of 155429 tetrahedron elements and 271683 nodes were used, after a 10% convergence test. Two materials, lithium disilicate and feldspathic ceramics, were simulated. A static load of 100 N on 45º was applied on the incisal and middle thirds of the palatal tooth region, guided by the occlusal plane. The base was constrained in all directions. The Maximum Principal Stress was the failure criteria chosen for the analysis. Results: The Finite Element Analysis showed that the most conservative designs presented less stress concentration on the ceramic veneer. However, the highest tensile stress concentrations were observed on lithium disilicate veneer with extend design, on the middle third. The type of occlusal contact presented different stress patterns among the preparation designs; the incisal contact showed higher stress concentration compared to middle third contact regardless the ceramic material. Conclusions: To perform a ceramic veneer in upper central incisor, the feldspathic ceramic presented promising results and should be recommended when the extended design was done. Regarding contact types, the incisal contact is more prone to failure regardless the ceramic and preparation design. Keywords Ceramics; Dental veneers; Finite element analysis.

Physiological Response of a Natural Central Incisor Tooth to Various Loading Conditions: A 3D Finite Element Study

“…These observations are consistent with the study [33] which showed that the narrow structure at the crown tip causes high stresses and bending in the crown. The present numerical results also match other studies where high stresses were reported on the enamel surface within top 1/3 rd region of the crown [19,36,45,48].…”

Effect of Different Ceramic Materials on Fatigue Resistance and Stress Distribution in Upper Canines with Palatal Veneers

“…Finite element studies have concluded that the combination of ceramic and cement can affect the performance of ceramic veneers in upper central incisors. 37 45 46 In addition, Tribst et al 45 evaluated occlusal veneers in posterior teeth and concluded that than the higher elastic modulus of the material than higher the stress magnitude. Corroborating with that, in the present study the PICN samples showed lower stress concentration in relation to the restoration, but not in relation to the cement layer.…”

Polymerization Shrinkage, Hygroscopic Expansion, Elastic Modulus and Degree of Conversion of Different Composites for Dental Application

“…For dental composites, in order to effectively reduce the polymerization stress during resin placement, a material with low post-gel shrinkage must be associated to a relatively low elastic modulus [2]. This can be justified because, in summary, the higher the elastic modulus of the restorative material, the smaller the deformation of dental structures under the same stress [36]. However, a reduction in the dental composite elastic modulus could lead to low hardness and low wear strength.…”

“…After that, the software determines by means of a numerical calculation from the acoustic signal that was captured in order to obtain the frequency spectrum (fast Fourier transform). Based on this, the dynamic elastic modulus was determined using the ASTM standard, which considers the specimen geometry, mass, dimensions, and frequencies obtained using the equipment [35,36]. The characterization of the Poisson ratio using impulse excitation technique occurred indirectly.…”