Purpose: Previous studies have shown the relationship of individual clinical variables to the survival of Dicor (Corning Glass Works) restorations. The purpose of the present investigation was to examine the effect of combinations of these variables on the intraoral survival of Dicor restorations. Materials and Methods: Dicor glass-ceramic restorations (n = 1,444) were placed in 417 adult patients. Failure was defined as a restoration that required remake because of material fracture. The survival of restorations with different combinations of variables that were each individually associated with survival was described using Kaplan-Meier survivor functions. The statistical significance of differences in survival between different combinations of specific predictor variables was examined using the proportional hazards model. Results: Kaplan-Meier survival analysis indicated that significantly worse survival rates were found for restorations that included combinations of molar teeth, a dentin core, and a glass-ionomer luting agent; molar teeth, a dentin core, and a resin luting agent; and single-rooted teeth, a dentin core, and a glass-ionomer luting agent than for any other combinations tested. The Cox proportional hazards model described a hazard ratio of 3.37 (95% confidence interval [CI]: 2.23 to 5.08) for molar teeth (versus single-rooted teeth), 2.65 (95% CI: 1.44 to 4.87) for dentin core (versus gold core), 2.35 (95% CI: 1.58 to 3.51) for men (versus women), and 1.72 (95% CI: 1.13 to 2.60) for glass-ionomer luting agent (versus resin) after adjusting for the other variables in the model. Conclusion: Factors beyond individual restoration design impact the survival of Dicor glass-ceramic. These include sex, tooth position, and restorations luted to gold core foundation bases.

Wenn Zahnprothetiker und Zahntechniker gut zusammenarbeiten, kann das die Ästhetik und das funktionelle Ergebnis der Restaurationen sehr verbessern. Wenn in jeder Disziplin ein Verständnis für die Stärken und Herausforderungen der jeweils anderen entwickelt wird, kann gemeinsam ein Behandlungsplan aufgestellt werden, der zum Erfolg führt. Mit dem diagnostischen Wax-up erhält das Dentalteam eine dreidimensionale Darstellung des Problems. Außerdem kann der Patient das Problem betrachten und sich an der Diskussion über die Lösungsmöglichkeiten beteiligen. Intraorale Aufzeichnungen, die der Prothetiker vornimmt, werden zusammen mit dem Zentrikregistrat des Technikers verwendet, um die Modelle regelrecht einzuartikulieren. Wenn Prothetiker und Techniker sich darüber einig sind, welche Materialien zur Anfertigung der provisorischen Prothese und des Meistermodells verwendet werden sollen, kommen genauere und funktionelle Resultate zustande. Die Zahnpräparationen sind von besonderem Interesse. Die Form der Ränder kann dem Zahntechniker helfen, leicht ein akkurates Modell anzufertigen. Ein während der Behandlung gefertigtes Wax-up erlaubt den umfassenden Austausch von Informationen zu der Restauration zwischen dem Prothetiker, dem Zahntechniker und dem Patienten. So wird sichergestellt, dass alle Beteiligten mit dem Aussehen und der Funktion der Restauration zufrieden sind, ehe die definitive Versorgung angefertigt wird. Sehr wichtig sind die Art des Materials und die Farbeigenschaften der definitiven Prothese, und wenn das Können und die Erfahrung des Prothetikers und des Zahntechnikers gemeinsam angewendet werden, entsteht ein hervorragendes Resultat. In diesem Artikel werden einzelne Punkte im Restaurationsprozess vorgestellt, die für die gemeinsamen Anstrengungen, auf ein gutes Endergebnis hinzuarbeiten, von entscheidender Bedeutung sind.

A collaborative relationship between prosthodontists and dental technicians can greatly improve the esthetic and functional results of restorations. When each discipline takes the time to understand the strengths and challenges of the other, together they can formulate a treatment plan that will culminate in a successful result. The diagnostic waxup gives the dental team a threedimensional illustration of the problem and allows the patient to view the problem and discuss solutions. Intraoral records taken by the prosthodontist are used with the technician's centric relation jigs to properly mount the casts. When the prosthodontist and technician agree on materials to be used in the fabrication of the provisional prosthesis and master dies, more accurate and functional results are achieved. Of special interest are the tooth preparations: The shape of the margins can enable the dental technician to easily create an accurate restoration. A treatment waxup allows full communication of information about the restoration between the prosthodontist, dental technician, and patient, ensuring that all three parties are satisfied with the look and function before the definitive restoration is made. The type of material and the color properties for the definitive restoration are of utmost importance, and the combined skills and experience of the prosthodontist and dental technician can create an excellent result. This article defines specific points in the restorative process when a collaborative effort between the prosthodontist and the dental technician dramatically improve the end result.

Purpose: This investigation compared initial and fatigue strengths of particle-abraded ceramics to those of as-polished alumina and zirconia ceramics in crown-like layer structures. Materials and Methods: Alumina or zirconia plates bonded to polycarbonate substrates were subjected to single-cycle and multi-cycle contact (fatigue) loading. Cementation surfaces of the ceramic were damaged by controlled particle abrasion, indentation with a sharp diamond at low load, or a blunt indenter at high load. The stresses needed to initiate radial fractures were evaluated. Results: The strengths of specimens were lowered by fatigue loading. After the equivalent of 1 year of occlusal contacts, the strengths of undamaged specimens degraded to approximately half of their single-cycle values. In particle-abraded specimens, an additional 20% to 30% drop in strength occurred after several hundred load cycles. Particle abrasion damage was approximately equivalent to damage from sharp indentation at low load or blunt indentation at high load. Conclusion: Damage from particle abrasion, not necessarily immediately apparent, compromised the fatigue strength of zirconia and alumina ceramics in crown-like structures. In fatigue, small flaws introduced by particle abrasion can outweigh any countervailing strengthening effect from compression associated with surface damage or, in the case of zirconia, with phase transformation.