Zirconia: Established facts and perspectives for a biomaterial in dental implantology

Abstract

Currently, zirconia is widely used in biomedical area as a material for prosthetic devices because of its good mechanical and chemical properties. Largely employed in clinical area for total hip replacement, zirconia ceramics (ZrO 2 ) are becoming a prevalent biomaterial in dentistry and dental implantology. Although titanium is used in dental implantology currently, there is a trend to develop new ceramic-based implants as an alternative to monolithic titanium. This article reviews the evolution and development of zirconia through data published between 1963 and January 2008 in English language. Articles were identified via a MEDLINE search using the following keywords: zirconia, zirconia/biocompatibility, zirconia/osseointegration, zirconia/periointegration, zirconia/review, and zirconia/bacterial adhesion or colonization. This review of the literature aims at highlighting and discussing zirconia properties in biological systems for their future use in dental implantology. In conclusion, zirconia with its interesting microstructural properties has been confirmed to be a material of choice for the ''new generation'' of implants, thanks to its biocompatibility, osseoconductivity, tendency to reduce plaque accumulation, and interaction with soft tissues, which leads to periointegration. However, scientific studies are promptly needed to fulfill gaps like long-term clinical evaluations of ''all zirconia implants,'' currently leading to propose an alternative use of ''hybrid systems'' (i.e., titanium screw with zirconia collar) and also bacterial colonization of zirconia. Moreover, there is a permanent need for consistent information about topography and chemistry of zirconia allowing easier cross-product comparisons of clinical devices. '

Hard and soft tissue responses to three different implant materials in a dog model

“…Zirconia dental implants have emerged as an alternative to titanium (Ti) implants in recent years [1][2][3] . Yttriastabilized tetragonal zirconia polycrystals (Y-TZP) are now commonly used, achieving good long-term prognosis as an artificial joint material in medical disciplines 4) .…”

Initial attachment of human oral keratinocytes cultured on zirconia or titanium

“…Moreover, since Ti originally having the characteristics of biotolerant which cause ion elution by corrosion in some environments, Ti implants have been reported to trigger allergic reactions [1][2][3] . Recently zirconia has drawn attention as a potential alternative to Ti, as it allows both allergic reactions and esthetic problems to be avoided 4,5) . Yttrium oxide-stabilized tetragonal zirconia polycrystals (TZP) are used in dentistry and show outstanding mechanical, biocompatible and esthetic performance.…”

Effect of differences in coefficient of thermal expansion of veneer and Y-TZP ceramics on interface phase transformation

“…The development of computer-aided design/computer-assisted manufacturing (CAD/CAM) technologies has enabled the production of complete and partial coverage crowns and partial fixed dental prostheses from high-strength zirconia. [1][2][3][4][5][6][7] Zirconia ceramic occurs in 3 modifications: the monoclinic (m) phase (stable up to 1170 C), the tetragonal (t) phase (stable up to 2370 C), and the cubic (c) phase (stable up to 2680 C). The c phase has moderate mechanical properties, the m phase shows reduced mechanical performance and is less dense than the other modifications of zirconia, and the t phase provides superior mechanical properties.…”