ABSTRACT
STATEMENT OF PROBLEM: Evidence is limited on the efficacy of zirconia-based fixed dental prostheses. PURPOSE: The purpose of this systemic review was to assess zirconia-based FDPs in terms of survival and complications. MATERIAL AND METHODS: Searches performed in PubMed databases were enriched by hand searches to identify suitable publications. The keywords used were: "zirconia" and "fixed dental prosthesis," "zirconia" and "crown," "zirconia" and "fixed partial denture" and "humans," "zirconia" and "crown" and "humans," "crown" and "all-ceramics," and "fixed partial denture" and "all-ceramics". Titles and abstracts were read to identify literature that fulfilled the inclusion criteria. Only peer reviewed clinical studies published in the English language from January 1999 through June 2011 were included. RESULTS: Twelve clinical studies based on zirconia, framework design, and porcelain veneering technique met the inclusion criteria. Of the studies identified, 1 was a randomized clinical study with 3-year follow-up results; the others were cohort prospective studies. Clinical complications included chipping of veneering porcelain, abutment failure, and framework fracture. One study investigated pressed ceramics as the veneering material and found no chipping of veneering porcelain after 3 years. CONCLUSIONS: Short term clinical data suggest that zirconia-based fixed dental prostheses may serve as an alternative to metal ceramic fixed dental prostheses in the anterior and posterior dentition.
Subject(s)
Crowns , Dental Materials/chemistry , Denture, Partial, Fixed , Zirconium/chemistry , Crowns/standards , Dental Porcelain/chemistry , Dental Restoration Failure , Dental Veneers/standards , Denture, Partial, Fixed/standards , Humans , Survival AnalysisABSTRACT
STATEMENT OF PROBLEM: Fracture of denture teeth from the denture base is a common problem associated with dental prostheses. Fractured tooth surfaces treated with chemical agents and mechanical features have the potential for improved repair strength. PURPOSE: The purpose of this study was to compare bond strengths of denture teeth to autopolymerized repair acrylic resin after various surface treatments, before and after cyclic loading. MATERIAL AND METHODS: Mandibular lateral incisor denture teeth were selected and ground on the ridge-lap portion using a standardized jig. Specimens with a ground surface were used as controls. The experimental groups included: ground plus airborne-particle abraded, ground plus diatoric recess, and ground plus an experimental bonding agent. The teeth were affixed by an autopolymerized repair acrylic resin to denture bases. Specimens (n=10) were subjected to compression testing (5 mm/min) at a 135-degree angle, before and after 14,400 loading cycles at 2 Hz and 22 N. Peak load to dislodgement was recorded and statistically analyzed (2-way ANOVA, Tukey HSD, alpha=.05). The specimens were then examined using x10 magnification, and fractures were categorized as adhesive, cohesive, or mixed. RESULTS: The mean bond strengths ranged from 26.3 N to 44.2 N. There were no significant differences in fatigue versus nonfatigue strength values within each group (P=.244). Significant strength differences were found (P<.001) between the ground control, diatoric recess, and bonding agent groups. Microscopic examination revealed that the bonding agent group obtained the highest percentage of mixed-type fractures. CONCLUSIONS: The use of a bonding agent and the placement of a diatoric recess in the denture tooth resulted in higher bond strengths than grinding alone. Cyclic loading had no significant impact on the bond strength of denture teeth to the autopolymerized repair acrylic resin.
