A systematic review of the survival and complication rates of zirconia‐ceramic and metal‐ceramic single crowns

Abstract

Objectives:The aim of the present systematic review was to analyze the survival and com plication rates of zirconiabased and metalceramic implantsupported single crowns (SCs). Materials and Methods: An electronic MEDLINE search complemented by manual searching was conducted to identify randomized controlled clinical trials, prospective cohort and retrospective case series on implantsupported SCs with a mean followup time of at least 3 years. Patients had to have been clinically examined at the followup visit. Assessment of the identified studies and data extraction was performed independently by two reviewers. Failure and complication rates were analyzed using robust Poisson's regression models to obtain summary estimates of 5year proportions. Results: The search provided 5,263 titles and 455 abstracts, fulltext analysis was performed for 240 articles, resulting in 35 included studies on implantsupported crowns. Metaanalysis revealed an estimated 5year survival rate of 98.3% (95% CI: 96.8-99.1) for metalceramic implant supported SCs (n = 4,363) compared to 97.6% (95% CI: 94.3-99.0) for zirconia implant supported SCs (n = 912). About 86.7% (95% CI: 80.7-91.0) of the metalceramic SCs (n = 1,300) experienced no biological/ technical complications over the entire observation period. The corresponding rate for zirconia SCs (n = 76) was 83.8% (95% CI: 61.6-93.8). The biologic outcomes of the two types of crowns were similar; yet, zirconia SCs exhibited less aesthetic complications than metalceramics. The 5year incidence of chipping of the veneering ceramic was similar between the material groups (2.9% metalceramic, 2.8% zirconia ceramic). Significantly (p = 0.001), more zirconiaceramic implant SCs failed due to material fractures (2.1% vs. 0.2% metalceramic implant SCs). No studies on newer types of monolithic zirconia SCs fulfilled the simple inclusion criteria of 3 years followup time and clinical examination of the present systematic review. Conclusion: Zirconiaceramic implantsupported SCs are a valid treatment alternative to metalceramic SCs, with similar incidence of biological complications and less aesthetic problems. The amount of ceramic chipping was similar between the materialgroups; yet, significantly more zirconia crowns failed due to material fractures. K E Y W O R D Sbiological, complications, fixed dental prostheses, implant crown, metaanalysis, metal ceramics, success, survival, systematic review, technical, zirconia frameworkThis is an open access article under the terms of the Creative Commons AttributionNonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

Retrospective clinical evaluation of implant‐supported single crowns: Mean follow‐up of 15 years

“…Indeed, the other reasons for the removal or replacement of the crowns were not technical, for example “esthetic issue,” “crown in infraposition in comparison to adjacent teeth,” “the patient's bite was raised,” “change to another type of prosthesis,” and these accounted for more than half of the here so‐called crown failure. Concerning the technical reasons, these figures are in accordance with the results of many of the clinical studies included in a recent review on the subject (Pjetursson et al, ) although few of those studies evaluated a similar number of single crowns as in the present study, and none had a mean follow‐up as long as in the present study.…”

“…Implant‐supported single crowns have many advantages over a fixed partial denture, namely a decreased risk of caries and endodontic treatment of the abutment teeth (and therefore a decreased risk of abutment tooth loss from caries or endodontic failure), improved ability to clean the proximal surfaces of the adjacent teeth (decreasing the risk of decay and periodontal disease), maintenance of bone in the edentulous site, psychological advantage, and among others (Misch, ). Despite all these advantages, single crowns supported by dental implants are not free from complications (Pjetursson et al, ; Sailer, Muhlemann, Zwahlen, Hammerle, & Schneider, ). The aim of the present retrospective clinical study was to assess the clinical outcomes of implant‐supported single crowns and the supporting implants after a mean follow‐up of 15 years.…”

Full‐zirconia single‐tooth molar implant‐supported restorations with angulated screw channel abutments: A 1‐year prospective case series study

“…Dental implant survival in cases of replacement of single missing teeth in the posterior region of the maxilla and mandible is high . However, implant‐supported restorations are prone to a number of complications, such as loosening of abutment screws and cement retention, peri‐implant mucosa infection due to cement remnants, and fracture of veneering ceramics …”

“…Zirconia‐based implant‐supported single restorations are rated as highly successful with a cumulative 5‐year survival rate of 97.1%. However, the most common complication reported is the fracture of the veneering material, especially in the posterior region . The excellent mechanical properties of monolithic zirconia could help overcome this technical complication .…”

“…The excellent mechanical properties of monolithic zirconia could help overcome this technical complication . Nonetheless, there is only scarce clinical evidence in support of full‐contour zirconia implant‐supported single restorations, while clinical evaluation of full‐contour zirconia restorations with angulated screw channel abutments has yet to be published. Also, the material properties of the restoration itself may have an impact on bone surrounding the implant.…”