Title Traditional Zirconia Resin-Bonded Fixed Dental Prostheses (RBFDPs) Can Be Successful, but the Evidence Is Still Lacking for Comparison of the Bond Strength Between Traditional and Translucent Zirconia
Clinical Question For patients receiving zirconia RBFDPs, would translucent zirconia (4 mol% or 5 mol% partially stabilized zirconia) bonded with a resin cement decrease bond strength, leading to an increased loss of retention, compared with traditional zirconia (3 mol% yttria-stabilized tetragonal zirconia polycrystal)?
Clinical Bottom Line With proper pretreatment of zirconia bonding surface and appropriate resin cement selection and bonding protocol, traditional zirconia RBFDPs can have excellent survival and success rates. More laboratory studies are necessary to investigate the bond strength of traditional and translucent zirconia. Long-term clinical studies of translucent zirconia RBFDPs are also indicated to validate laboratory studies.
Best Evidence  
PubMed ID Author / Year Patient Group Study type
(level of evidence)
28985448Chen / 2018208 patients with 242 all-ceramic RBFDPs in 8 included studies Systemic Review of Randomized Clinical Trial and Cohort Studies
Key resultsThe all-ceramic RBFDPs’ overall estimated 5-year survival, debonding, and framework fracture rates were as follows: 91.2% (95% CI: 75.3 to 95.0); 12.2% (95% CI: 4.1 to 30.2); 4.8% (95% CI: 1.0 to 19.5). As compared to the two-retainer RBFDPs, the cantilever RBFDPs had a higher survival rate (98.1% vs 92%, p < 0.01), a lower debonding rate (6.1% vs 7.2%, p < 0.05), and a lower framework fracture rate (1.4% vs 10.7%, p < 0.01).
28688950Kern / 201787 patients with 108 anterior cantilever zirconia RBFDPsRetrospective Cohort Study
Key resultsThe overall 10-year success and survival rates were 92.0% (six debonded restorations) and 98.2% (one lost/removed restoration per patient’s request for an implant-supported crown).
Evidence Search “Zirconia” [All Fields] AND “Resin Bonded Fixed Dental Prostheses” [All Fields] AND “Long Term” [All Fields] AND “Survival”
Comments on
The Evidence
Validity: Chen et al. systemically reviewed eight studies including five prospective cohort studies, two retrospective cohort studies, and one randomized clinical trial (RCT), mostly weak on the hierarchy of evidence. The Newcastle-Ottawa scale was used to assess the quality of seven cohort studies, and the scores ranged from three to five points implying a relatively higher risk of bias. The RCT quality was assessed based on the Cochrane Handbook for Systemic Reviews of Interventions. Poisson regression was applied to estimate survival and complication rates. Kern et al. followed 87 patients with missing incisors, and all treated with 108 cantilever zirconia RBFDPs. Patients were followed and clinically examined at least annually anywhere from 35 months to 185 months. Perspective: Zirconia has the highest strength amongst all dental ceramics. Polished zirconia wears opposing enamel significantly lower than a veneering porcelain. Despite its favorable properties as restorative material, traditional zirconia’s opacity has been a challenge to overcome. There have been developments of more translucent zirconia within recent years, and its application has broadened to restore highly esthetic anterior regions. Although its translucency is improved, strength and toughness have been shown to diminish compared to traditional zirconia. Physical properties of translucent zirconia have been actively investigated by many researchers. Strong and durable resin bonds are required for long-term prognosis. However, studies comparing bond strength between traditional and translucent zirconia are still scarce and few laboratory studies are available. The evidence is still limited to traditional zirconia. More cohort studies and randomized clinical trials need to be conducted to look at the survival rate of translucent zirconia.
Applicability Zirconia RBFDPs can be a viable treatment option for patients with missing anterior teeth, especially young patients who are not eligible for implant-supported restorations. The main advantages are minimally invasive preparation without local anesthesia, lower cost, less treatment time, and functionally sound and esthetically pleasing outcome. Disadvantages are risks for debonding, porcelain chipping and framework fracture. With improvements in ceramic materials and bonding techniques, traditional zirconia RBFDPs can provide an excellent long-term prognosis as a permanent restoration, but further long-term clinical studies on translucent zirconia are still needed.
Specialty (General Dentistry) (Prosthodontics) (Restorative Dentistry)
Keywords Zirconia, Resin-Bonded Fixed Dental Prostheses, Long-Term Survival, Bond Strength
ID# 3414
Date of submission 11/27/2019
E-mail minh@livemail.uthscsa.edu
Author Hoon Min, DMD
Co-author(s) Alyssa-Joy Oviatt, DDS
Co-author(s) e-mail oviatt@livemail.uthscsa.edu
Faculty mentor Aaron B. Harding, DMD, MS, FACP
Faculty mentor e-mail aaron.b.harding2.mil@mail.mil
Basic Science Rationale
(Mechanisms that may account for and/or explain the clinical question, i.e. is the answer to the clinical question consistent with basic biological, physical and/or behavioral science principles, laws and research?)
None available
Comments and Evidence-Based Updates on the CAT
None available