Three-dimensional finite element analysis of thermal shock in a premolar with a composite resin MOD restoration

3D finite element analysis on esthetic indirect dental restorations under thermal and mechanical loading

“…As to hot loading conditions for a tooth restored with resin by direct method, Fenner et al [7] obtained a tensile stress of 9 MPa at the dentin-restoration interface. They had not considered this value relevant as compared to the adhesive strength of the resin, which assumed resistance value was 23 MPa.…”

“…The time period considered in the analysis was 2 s, corresponding to normal duration of exposure to hot and cold food. According to Fenner et al [7], this is the period of time that a hot liquid is retained in the mouth at near constant temperature. A standard finite difference method, with an adaptive algorithm that recalculates an appropriate time-step was used by Fenner et al [7], who state that contact occurs between food at the lingual and occlusal surfaces (corresponding to the mastication and internal regions).…”

“…Figure 8 shows the external stress distribution for this load case. Maximum and minimum principal stresses (r 1 and [6,7] 210 [21] 7.1 [21] 74.0 [7] 0.19 [13] 50 [2] 149 [10] r 3 ) for combined cold temperature and hot temperature coupled with mechanical loads are shown in Table 3.…”

“…The polymerization contraction that occurs during curing of the resin cement can lead to stresses at the interface between the restoration and dental tissue [11]. Additional interfacial stresses are subsequently superimposed by mechanical loading on the tooth during mastication, and by the thermal loading at drinking of hot and cold liquids [7]. The investigation of the effects of these thermal changes on restored teeth, and the associated bond failure and microleakage, either in vitro or in vivo, present serious experimental difficulties.…”

Fatores preditores da tensão de contração para interfaces de restaurações adesivas em cavidade de classe I

“…Rápidas mudanças no ambiente oral são relatadas na literatura entre 0°C e 67°C 16 , sendo que as temperaturas mais baixas são mais comuns no surgimento de tensões interfaciais que as altas 17 . Autores na área de Engenharia lidam com o problema de concentração de tensões próxima à área de aplicação de carga por meio da aplicação deste princípio, já que este estabelece que sistemas de carregamentos estáticos equivalentes produzem a mesma tensão e deformação dentro de um mesmo corpo, na região imediatamente próxima à aplicação da carga.…”