Zirconia biocompatibility in animal studies - A systematic review

Zirconia is a metal used in dental implantology. Its biocompatibility was studied in vitro and in vivo, results of the studies being analyzed in reviews and meta analyses. The aim of this systematic review was to evaluate biocompatibility of zirconia in animal studies in vivo expressed as results of histomorphometric tests. Databases were searched from 1980 until February 2016, with different combination of the following MeSH terms: zirconium, biocompatibility, dental implants, in vivo, animal studies. Letters to the editors, case reports, commentaries, review articles and articles published in other languages then English were excluded. The search of PubMed, ScienceDirect and Google Scholar databases yielded 690 titles. After abstract screening and duplicate discarding, 50 articles were identified and finally, 40 were included in the review. Most of the studies compared zirconia with titanium, a common material for dental implants. In majority of the studies zirconia showed a similar osseointegration with titanium. Surface implant treatments, like sandblasted and etched zirconia (ZrO2-SLA), alumina toughed zirconia (ATZ), and powder injection molding (PIM) were used to improve osseointegration of zirconia with good results. Between them, microstructured zirconia (ZiUnite) and sandblasted zirconia (ZrO2-SLA) had the best values of osseointegration. In the light of histomorphometric test, zirconia, no matter physical and structural forms tested, is a biocompatible material. © 2017 Trans Tech Publications, Switzerland.