Resistencia a la fractura ante cargas compresivas en restauraciones endocrown de disilicato de litio con dos diseños de preparación en primeros premolares superiores

Abstract

The purpose of this in vitro study was to evaluate the resistance to fracture under compressive loads in endocrown lithium disilicate restorations with two preparation designs. Methods: the posteriorly extracted maxillary first premolar teeth treated endodontically were divided into two groups, Group A: the butt joint preparation without shoulder termination and group B: the preparation with axial reduction and 1 mm shoulder finishing line. Cemented and tested for resistance to fracture. Results: the preparations with terminal lines, presented a greater compressive resistance; half of the restorations with values above 1414.1MPa, a quarter with values below (1357.8MPa) and only a quarter of the sample evaluated above (1795.3MPa). Through the descriptive analysis of the variables, comparing the compressive strength with a statistically significant difference (p-value = 0.017), of the time, in which no statistically significant difference was found (p-value = 0.32). Conclusions: Within the limitations of this study, we can emphasize that only axial loads were executed in the central fossa of the premolars. Cyclic load testing is recommended by exerting shear or tangential forces. Evaluate fractures that compromise not only the restoration but also the dental remnant to be treated.