Factors essential for successful all-ceramic restorations.
BACKGROUND: The use of all-ceramic crowns is increasing, and this trend will continue. However, all-ceramic systems are not all the same. They differ considerably in their relative esthetic potential, their physical properties and evidence base relative to longevity. The use of an all-ceramic system does not guarantee outstanding esthetics. CONCLUSIONS: Some all-ceramic systems can provide superior esthetic results compared with metal-ceramic restorations. Zirconia-cored crowns are the strongest all-ceramic system and may provide improved esthetic results compared with metal-ceramic crowns. No all-ceramic restoration has been shown to have a life span equivalent to that of metal-ceramic restorations. Further clinical trials are needed. PRACTICE IMPLICATIONS: Clinicians should choose appropriate all-ceramic restorations on the basis of their patients' needs. Currently available evidence indicates that clinicians should not use all-ceramic crowns on molars; in addition, posterior fixed partial prostheses fabricated with all-ceramic materials have a high likelihood of failure. (+info)
Which all-ceramic system is optimal for anterior esthetics?
BACKGROUND: As ceramic materials for dentistry evolve and patients' demand for esthetic restorations increases, practitioners must keep up with the science as well as the demand. The authors offer guidance to the practitioner in selecting the appropriate all-ceramic systems for crowns when faced with different esthetic demands. CONCLUSIONS: Clinicians should reserve dental ceramics with high translucency for clinical applications in which high-level esthetics are required and the restoration can be bonded to tooth structure. Ceramics with high strength tend to be more opaque and pose a challenge when trying to match natural tooth color, but they can mask discoloration when present. PRACTICE IMPLICATIONS: Knowledge of the optical properties of available ceramic systems enable the clinician to make appropriate choices when faced with various esthetic challenges. (+info)
Correlation between metal-ceramic bond strength and coefficient of linear thermal expansion difference.
Metal-ceramic dowel crown restorations for severely damaged teeth: a clinical report.
This clinical report describes an alternative prosthodontic treatment of a patient who had severely damaged endodontically-treated first molar teeth in all quadrants of her mouth. The young patient's severely damaged permanent molar teeth were treated with a restoration combining the advantage of the esthetics of dental porcelain, reinforced with the underlying cast gold dowel crown. Using this technique, the remaining sound tooth structure was preserved with function and esthetics accomplished. The described metal-ceramic one piece dowel crown restoration seemed to perform without any problems for the 12 month evaluation time. (+info)
Effect of casting atmosphere on the shear bond strength of a ceramic to Ni-Cr and Ni-Cr-Be alloys.
Effects of metal primers on bonding of adhesive resin cement to noble alloys for porcelain fusing.
This study evaluated the effects of metal primers on the bonding of adhesive resin to four pure metals (Au, Pd, Ag, Cu) and two noble alloys for porcelain fusing (high-gold and high-palladium content alloys). Bonding surface was polished with 600-grit silicon carbide paper and primed with one of the three metal primers (V-Primer, Metaltite, and M.L. Primer). Bonded specimens were fabricated by applying adhesive resin (Super-Bond C&B) on the primed surface. Shear bond strength (SBS) was determined both before and after thermocycling (4-60 degrees C for 2,000 cycles). The highest SBS values to each pure metal after thermocycling were 33.5 MPa for Au by M.L. Primer, 35.0 MPa for Ag by V-Primer, and 34.4 MPa for Cu by Metaltite. SBS to high-gold content alloy after thermocycling was 33.3 MPa by M.L. Primer. None of the primers was effective for pure Pd and high-palladium content alloy after thermocycling. (+info)