Abstract
Post-and-core systems were introduced into dentistry to provide retention and support for crowns when an insufficient amount of dentin is available for them after root canal treatment. Cast metal post-and-core systems have been successfully used for many years, due to their superior physical properties. However, the difference in the modulus of elasticity between the metal post-and-core and the surrounding dentin concentrated the stresses within the radicular dentin, causing root fracture. Moreover, the increased interest for a more pleasing aesthetic appearance, particularly in the anterior regions under a translucent all-ceramic crown, necessitated the development of more aesthetically pleasing tooth-colored post-and-core systems to replace the metal ones. Currently, prefabricated tooth-colored posts are extensively used to fulfill aesthetic requirements; one of these materials is the zirconia ceramic post system, whose rapid growth and development led to the publication, in the past few years, of many in vitro studies investigating its properties. The aim of this article was to present data about fracture resistance, surface treatment, and long-term clinical evaluation of teeth restored with zirconia ceramic posts. We also examined the acceptability of prefabricated zirconia posts compared to fiber posts, when used to restore endodontically treated anterior teeth, the use of a new technology to construct zirconia post-and-core systems, and the cytotoxicity and biocompatibility of zirconia with or without luting cement. According to the results obtained, zirconia posts show acceptable fracture resistance, clinical durability, improvement in the fabricating techniques, and acceptable biocompatibility.