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Objective: The purpose of this study was to evaluate the cervical marginal fit of porcelain laminate veneer (PLV) restorations made from two different types of CAD/CAM ceramic laminates: CEREC C PC and E.max (LD). Materials and Methods: This in-vitro experiment used a total of 32 human maxillary first premolars that were clean and free of any cracks or caries, extracted for orthodontic purposes. The samples were divided in a random way into two study groups: A and B (n = 16). Each sample was mounted on a dental surveyor and a silicon impression was made to create a silicone index for each tooth in both groups. Standardized preparation was carried out for all the samples by using preparation bur kit for the ceramic veneer system. Subsequently, digital impressions were made for all the samples by using Trios 3 shape intraoral camera (Sirona Dental Systems). The design of veneer restorations was made using Sirona inLab CAD SW 16.1 with CEREC inLab MC XL (Dentsply, Sirona Dental Systems, Bensheim, Germany). The veneer restorations were cemented using 3M RelyX veneer resin cement (3M ESPE, Seefeld, Germany) and the samples kept in distilled water for two weeks at 37 °C. All the specimens were subjected to thermocycling in a water bath with temperature varying between 5 °C and 55 °C for 500 cycles. The cervical marginal fit of veneers was evaluated by a digital microscope after sectioning the embedded teeth in acrylic resin. Results: The lowest mean of cervical marginal gap was recorded for Group A (91.59431 ± 1.626069) which was restored with CEREC CAD/CAM veneers, while the highest mean value of the gap was recorded for Group B (106.48863 ± 2.506684) which was restored with IPS E.max CAD. The t-test showed that the type of porcelain veneer restoration had a highly significant effect on the cervical marginal fit (p ≤ 0.01). Conclusions: CEREC CAD/CAM veneers showed smaller cervical marginal gaps, indicating a better fit compared to the IPS E.max CAD. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to evaluate the effect of margin design changes on the stress distribution in zirconia-based full-crown restorations using three-dimensional finite element analysis. Methodology: For use in the design of full-crown restorations, tooth number 16 was prepared in chamfer step type on a maxillary tooth jaw model (AG-3: Tipodont, Frasaco, Germany). The prepared tooth was scanned using a desktop scanner, and a three-dimensional finite element analysis model was obtained. Zirconia frameworks are divided into three groups according to the margin design: uniform thickness hood type (Model A), ¾ partial crown form (Model B), and a lingual-band type (Model C). The crown form was completed using feldspathic porcelain as the superstructure material. To determine the stress distribution of the margin design on the restoration, the maximum principal stress (MPa) values under a 600 N vertical load were investigated. Results: The maximum stress on the zirconia framework was observed in Model A (82.90 MPa), and the maximum stress on the tooth was observed in Model B (49.34 MPa). The maximum stress on the feldspathic porcelain was highest in Model A (21.860 MPa), and the minimum stress on the tooth occurred in Model B (13.33 MPa). In the zirconia framework, the lowest stress was 11.54 MPa (Model B). Conclusion: The framework design was shown to affect the force generated on the restoration and transmitted to the tooth. The results of the present study will help dentists determine the ideal infrastructure design for zirconia-based restorations. Lingual band designs were found to be successful. [ABSTRACT FROM AUTHOR]

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This section offers ceramic art news briefs. The exhibit "Karl Hainichen Collection," held until June 12, 2011 at the Keramikmuseum Staufen in Staufen, Germany featured his collection of 100 ceramic art pieces made after World War II. Bonhams New Bond Street auctioned 38 pieces of Meissen porcelain art worth 500,000 pounds on December 8, 2010. The exhibit "Atles neu entdeckt," which was held until April 26, 2011, featured the Cremer Collection, which consisted of 5,000 works made in Germany.

The article discusses the importance of metal-ceramic crowns and pontics which designed to restore maxillary and mandibular masters model to the patients with partial dentures. Dentists from the University of Cologne stated that the dental materials are very effective especially on fixed porcelain dental works because they were already tested it for about 10 years in Germany. Based from the observations, the effectivity of removing the fixed bridgework and dentures would take an average of 4 to 6 years. Moreover, the possible effects of using porcelain materials for dental work is also considered.

The article presents ceramics classes held at TON-raum.com in Höhr-Grenzhausen, Germany. The seminar "Inlay and Artifacts," by Renée Reichenbach explains the applications of red and anthracite clay in ceramics, where various types of clay and porcelain slabs can be rolled in as inlay. "Painterly Surfaces," by Ute Großmann discusses colour theory, colour design, and the wax resist technique in ceramic art.

The article reports on the highlights of the Second International Porcelain Market held at Klaffenbach Castle near Chemnitz, Germany on March 17-18, 2012, and cites the winners of the Von Taube Prize 2012 including first placer Susanne Petzold and second placers Christine Salzwedel and Ulrike Sandner.