Failure Analysis of Zirconia Versus PolyEtherEtherKetone Custom Made Posts in Endodontically Treated Anterior Teeth. (An In vitro Study)

Abstract

Background: PolyEtherEtherKetone and zirconia are two recent esthetic post materials used in treatment of endodontically treated teeth. Although both materials share similar esthetic properties but have different mechanical properties which could affect their mode of failures. Therefore, the aim of the study was to analyze the failure modes of zirconia versus PolyEtherEtherKetone custom made posts in anterior endodontically treated teeth. Materials and Methods: Thirty-six anterior maxillary incisors with similar dimensions were collected, decoronated, endodontically treated, and post space prepared. The teeth were divided according to material of post into two groups: group (1) PolyEtherEtherKetone post and group (2) zirconia post. PolyEtherEtherKetone posts were surface treated via sulfuric acid while zirconia posts were sandblasted by 50um aluminum oxide particles. All posts were cemented using dual cure self-adhesive cement. Thermocycling at 5,000 cycles was done to all samples. Three slices of 2mm thickness were obtained from each sample. The samples were loaded to failure via universal testing machine at a crosshead speed of 0.5 mm/min. Failure modes were evaluated using a scanning electron microscope under magnifications of 52x, 250x and 400x.Results: There was no statistically significant difference between failure modes of the two post material types at the cervical, middle as well as apical root levels (P-value = 0.070), (P-value = 0.580) and (P-value = 1), respectively. Conclusions: The failure modes between both zirconia and PolyEtherEtherKetone posts were comparable, making them viable options as custom-made post materials. However, within the PolyEtherEtherKetone posts adhesive and adhesive-cohesive failures were more common while in zirconia posts cohesive failure was more dominant.