Failure modes of Y-TZP abutments with external hex implant-abutment connection determined by fractographic analysis

• Autor(a) principal: Basílio, Mariana de Almeida [UNESP]
• Data de Publicação: 2016
• Outros Autores: Delben, Juliana Aparecida [UNESP], Cesar, Paulo Francisco, Rizkalla, Amin Sami, Santos Junior, Gildo Coelho, Arioli Filho, João Neudenir [UNESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1016/j.jmbbm.2015.12.042; http://hdl.handle.net/11449/172439
• topic: Dental ceramic; Failure analysis; Fractography; Implant abutment; Zirconia

Yttria-stabilized tetragonal zirconia (Y-TZP) was introduced as ceramic implant abutments due to its excellent mechanical properties. However, the damage patterns for Y-TZP abutments are limited in the literature. Fractographic analyses can provide insights as to the failure origin and related mechanisms. The purpose of this study was to analyze fractured Y-TZP abutments to establish fractographic patterns and then possible reasons for failure. Thirty two prefabricated Y-TZP abutments on external hex implants were retrieved from a single-load-to failure test according to the ISO 14801. Fractographic analyses were conducted under polarized-light estereo and scanning electro microscopy. The predominant fracture pattern was abutment fracture at the connecting region. Classic fractographic features such as arrest lines, hackle, and twist hackle established that failure started where Y-TZP abutments were in contact with the retention screw edges. The abutment screw design and the loading point were the reasons for localized stress concentration and fracture patterns.