This invited talk would like to update the audience on state of the preclinical and clinical scientific background of zirconia ceramic oral implants. According to original work and reviews, osseointegration (bone integration) and soft tissue integration arenot different between titanium – as the implant material of choice - and zirconia implants when they present with similar surface topographies. Regarding stability, one-piece zirconia implants (with a diameter of ≥ 4 mm) are stable enough for long-term clinical use as has been shown in simulating tests. In general, two-piece implant systems with different geometries and designs are less resistant to artificial chewing forces. However, some of the two-piece designs also are stable enough for being clinically applied. 

Systematic reviews of the clinical use of zirconia implants show good short- and mid-term results for one-piece zirconia implants. Clinical data for two-piece implants arerare. For single tooth restorations or 3-unit fixed dental prostheses, the survival results of zirconia implants are comparable to the results of titanium implants. Therefore, zirconia implants may be considered as an addendum to titanium implants for situations where they are useful (patient request, known hypersensitivity to titanium, or questions of esthetics when titanium might appear inappropriate for a certain situation/condition). 

Future research needs to focus on the clinical application of two-piece implants and on the implant design (bone level implants, retention of the abutment to the implant). Furthermore, the topic of low thermal degradation ought to be evaluated regarding its effect on osseointegration