Bone and Joint Institute
Failure modes of Y-TZP abutments with external hex implant-abutment connection determined by fractographic analysis
Document Type
Article
Publication Date
7-1-2016
Journal
Journal of the Mechanical Behavior of Biomedical Materials
Volume
60
First Page
187
Last Page
194
URL with Digital Object Identifier
10.1016/j.jmbbm.2015.12.042
Abstract
© 2016 Elsevier Ltd. 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.