Are ceramic implant-supported single crowns clinically better than metal-ceramic implant-supported single crowns?

Data sources Data was collected from six databases (Medline, Embase, Web of Science, The Cochrane Central Register of Controlled Trials [CENTRAL], China National Knowledge Infrastructure [CNKI] and Chinese Biomedical Literature Database). Studies published in English and Chinese languages comparing ceramic and metal-ceramic implant-supported fixed dental prostheses (FDPs) were searched. The literature search was performed on studies published until 2018. Manual search of the reference lists of the identified articles was also performed to find related review articles and studies.Study selection Randomised controlled trials (RCTs), prospective and retrospective cohort studies involving the comparison of ceramic and metal-ceramic implant-supported FDPs were selected using the PICOS model for the meta-analysis. For ceramic and metal-ceramic single crowns, the survival rate, marginal adaptation, marginal bone loss, pocket probing depth, crown colour match and mucosal discolouration were assessed. The authors also included studies on survival rate of implant-supported fixed partial dental prostheses (FPDPs) in this meta-analysis.Data extraction and synthesis Two investigators independently screened the articles from the literature search and extracted and analysed data from the included studies. The quality of the included RCTs were assessed using the Cochrane collaboration tool for assessment of risk of bias. For the selected non-randomised studies, the quality and risk of bias were assessed using the Newcastle-Ottawa scale. Twenty studies were included in data synthesis.Results Of the selected 20 studies, ten were RCTs and ten were prospective or retrospective cohort studies.Conclusions The results of this study can be useful to clinicians in making decisions between ceramic and metal-ceramic implant-supported single crowns. This study concluded that the ceramic implant-supported single crown has better crown colour match over a metal-ceramic single crown, but poorer marginal adaptation, and there was no difference observed in other parameters studied (survival rate, marginal bone loss, pocket probing depth and mucosal discolouration). The conclusions on survival rate of implant-supported FPDPs needs to be further evaluated with RCTs with larger samples.