Moderators

Expert Panel

The proposed timing for a review or revision

A comparison of hard and soft tissue integration and the clinical prognosis of titanium and zirconium dioxide implants. The influence of the modification of the surface of ceramic implants on mechanical and biological properties. The long-term performance of one- and two-piece ceramic implants.

Keywords for recommendations: ceramic implant, one-piece, two-piece, titanium implant, implantology, zirconium dioxide implant, osseointegration, soft tissue integration, surface coating, surface modification, long-term prognosis

Hard and soft tissue integration

Titanium and zirconium dioxide implants present similar soft and hard tissue integration in pre-clinical and clinical studies. Similar to titanium implants, zirconium dioxide implants with moderately rough modified surfaces exhibit a faster osseointegration than untreated, relatively smooth ceramic surfaces (Roehling S,. et al., 2019; Schünemann F.H., et al., 2019). A faster maturation process of the soft tissue around zirconium dioxide implants has been observed (Roehling S., et al., 2019). Physicochemical modifications of ceramic surfaces with acid etching, sandblasting, laser treatment, UV light, etc., as well as surface coating with silicates, magnesium, graphene, dopamine and bioactive molecules have been shown to improve the mechanical and biological properties of zirconium dioxide implants in cell culture and animal studies (Hsu C.M., et al., 2019; Schünemann F.H., et al. 2019; Bergemann C., et al., 2015).

Clinical prognosis

Similar clinical results compared to titanium implants were demonstrated for zirconium dioxide implants in short-term clinical trials of up to 12 months (Afrashtehfar K.I., et al., 2020). One-piece zirconium dioxide implants also exhibit favorable clinical long-term results over a period of up to seven years in current prospective clinical studies, so that their clinical application as an alternative to titanium implants can be recommended without reservation in corresponding indications (Lorenz J., et al., 2019; Balmer M., et al. 2020). There is a lack of corresponding clinical long-term studies to date for two-piece zirconium dioxide implants, so these should instead be limited to clinical studies before routine use.

Appropriate materials or combinations of materials for the fixed, metal-free restoration of ceramic implants and the definitive incorporation of all-ceramic crowns and bridges.

Keywords for recommendations: ceramic implant, implantology, zirconium oxide, lithium disilicate, glass ceramic, veneering, cementing, excess removal, venting

Single crowns

Lithium disilicate has been clinically proven for the use of monolithic single crowns on ceramic implants. Veneers in the non-occlusion-bearing region do not represent a clinical limitation (Spies B.C., et al., 2017; Rabel K., et al., 2018; Spies B.C., et al., 2019). No clinical data is currently available for other high-strength glass ceramics (flexural strength >350 MPa). Currently, highly translucent (5Y-TZP) zirconium oxides are increasingly being used as monolithic crown material with initial promising experiences on implants. Clinical data is lacking for a final assessment (Edelhoff D., et al., 2019). Apart from heterogeneous experience, there is also no clinical data available for hybrid materials.

Bridges

There is clinical data for fully veneered zirconium oxide bridges on ceramic implants, which exhibit high survival and complication rates. The main complications were – as in other clinical studies – technical problems with the veneering ceramic (Pieralli S., et al., 2018; Spies B.C., et al., 2018). These problems and the further development of the technical possibilities led to the use of monolithic bridges made of zirconium oxide. From today’s perspective, 3Y and 4Y-TZP zirconium oxides can be recommended for indication with up to two bridge elements in the posterior teeth region (Cheng C.W., et al., 2018; Cheng C.W., et al., 2019). The 3-D guided insertion of one-piece ceramic implants helps to ensure a common insertion direction (Walker-Finch K., et al., 2020).

Incorporation

The requirements of the restoration materials must be taken into account when selecting the fastening material. The removal of excess conventional cements is easier than the removal of excess adhesive materials (Zaugg L.K,, Zehnder I., et al., 2018). Oral venting reduces excess cement without reducing in vitro mechanical strength (Schwedhelm E.R., et al., 2003; Zaugg L.K., Meyer S., et al., 2018).