Zirconia implants restored with single crowns or fixed dental prostheses: 5‐year results of a prospective cohort investigation

Abstract

Aim To evaluate the clinical and radiological outcomes of one‐piece zirconia implants restored with single crowns (SCs) or fixed dental prostheses (FDPs) over an observation period of 5 years in function. Materials and methods In a prospective cohort investigation with two investigational centers, one‐piece zirconia implants were placed in anterior and posterior sites. After a healing period of at least 2 months in the mandible and 4 months in the maxilla with immediate provisional reconstructions, the final all‐ceramic SCs or three‐unit FDPs were cemented. Patients were followed for 5 years. Clinical parameters and radiological measurements of the implants and the neighboring teeth were assessed. For the statistical analysis, linear mixed models were applied. Results A total of 71 implants were placed in 60 patients. Sixty‐three implants in 53 patients could be evaluated at the 5‐year follow‐up. Six patients with a total of seven implants were counted as dropouts. One implant did not achieve adequate osseointegration and had to be removed 5 weeks after implantation. The 5‐year survival rate was calculated as 98.4% (95% CI 91.6, 99.9). The mean overall marginal bone loss from implant placement to the 5‐year follow‐up was 0.7 ± 0.6 mm. After an initial mean marginal loss before loading the implants (0.7 mm), no further statistically significant change in marginal bone level (p = .458) could be observed. Conclusion The investigated one‐piece zirconia implant showed a high survival rate, very stable marginal bone, and mucosal margin levels after 5 years in function. Therefore, it can be considered safe and reliable for the reconstruction of implant‐supported SCs or FDPs over a mid‐term period.

A Prospective Clinical Cohort Investigation on Zirconia Implants: 5-Year Results

“…Mid-and long-term results are rare for zirconia ceramic implants [6][7][8]. Therefore, the present 5-year results of an alumina-toughened zirconia implant adds to the information on zirconia implants and confirms the initial positive clinical and radiographic results of the shorter-term outcomes of this type of implant system [25,26].…”

“…Currently available clinical data on zirconia implants are limited to fixed prosthetic rehabilitations (especially single crowns (SCs) and short-span fixed dental prosthesis (FDPs)) and show high short-term survival rates (98% after 1 year and 97% after 2 years), which are comparable to two-piece titanium implants [2][3][4][5]. Medium and long-term clinical data on zirconia implants are still scarce in the scientific literature [6][7][8]. Zirconia as a metal-free alternative to titanium for the manufacturing of implants is of interest for our patients, since this material can positively influence the esthetic outcome of a reconstruction due to the tooth-like color [9,10].…”

Thermal effects of various drill materials during implant site preparation—Ceramic vs. stainless steel drills: A comparative in vitro study in a standardised bovine bone model

“…Zirconium dioxide (ZrO 2 , zirconia), however, shows favourable physicochemical properties (high bending strength and fracture toughness) depending upon its composition and processing (Piconi & Maccauro, 1999; Sivaraman et al., 2018) as well as high biocompatibility similar to titanium (Benic, Thoma, et al., 2017; Bormann et al., 2012; Gahlert et al., 2012; Janner et al., 2018; Roehling et al., 2019). Although long‐term results for zirconia implants are still missing and elevated heat generation was reported in vitro during implant insertion with zirconia implants when compared to titanium implants (Zipprich et al., 2019), promising clinical data investigating the outcome of one‐piece zirconia implants after an observation period of 5 years have been recently obtained (Balmer et al., 2020). Newly developed two‐piece zirconia implants, which are supposed to overcome problems caused by challenging abutment angulations (Wenz et al., 2008), showed a similar screw‐retained stability in vitro (artificial ageing process) when compared to a conventional titanium‐based connection (Joos et al., 2020).…”

Clinical Longevity of Zirconia Implants with the Focus on Biomechanical and Biological Outcome

“…After publication of the systematic reviews (including the meta-review that relates to those), further results on zirconia ceramic implants appeared in the scientific literature (Table 1). Balmer and coworkers [69] and Kohal et al [73] presented the 5 year data of one-piece zirconia implants. Whereas in the former investigation Y-TZP implants were applied, in the latter, ATZ implants have been utilized.…”