The purpose of this study was to evaluate the clinical performance of laminate porcelain veneers bonded with a light-cured composite. Thirty patients were restored with 119 porcelain laminate veneers. The veneers were studied for an observation time of 7 years. Marginal adaptation, marginal discoloration, secondary caries, color match, and anatomic form were clinically examined following modified United States Public Health Service (USPHS) criteria. Each restoration was also examined for cracks, fractures, and debonding. Pulp vitality was verified. In addition, plaque and gingival indexes and increase in gingival recession were recorded. Survival rate evaluating absolute failures and success rate describing relative failures were statistically determined, using both restoration and patient-related analyses. On the basis of the criteria used, most of the veneers rated Alfa. After 7 years, the results of the clinical investigation regarding marginal adaptation and marginal discoloration revealed only 2.5% and 4.2% Bravo ratings, respectively, among the 119 initially placed veneers. Using the restoration as the statistical unit, the survival rate was 97.5%, with a high estimated success probability of 0.843 after 7 years. Using the patient as the statistical unit, the survival rate was 90.0% and the estimated success probability after 7 years was 0.824. Gingival response to the veneers was all in the satisfactory range. Porcelain laminate veneers offer a predictable and successful treatment modality giving a maximum preservation of sound tooth. The preparation, cementation, and finishing procedures adopted are considered key factors for the long-term success and aesthetical result of the veneer restorations.

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The purpose of this in vitro study was to compare the two-body wear resistance of human enamel, a pressable glass-ceramic (Imagine PressX), a type 3 gold alloy (Aurocast8), three resins composites currently available on the market (Enamel plus HRi, Filtek Supreme XTE, Ceram.X duo), and one recently introduced resin composite (Enamel plus HRi-Function). Resin composites were tested after simple light curing and after a further heat polymerization cycle. Ten cylindrical specimens (7 mm in diameter) were manufactured with each dental material according to standard laboratory procedures. Ten flat enamel specimens were obtained from freshly extracted human molars and included in the control group. All samples were subjected to a two-body wear test in a dual-axis chewing simulator over up to 120,000 loading cycles, against yttria stabilized tetragonal zirconia polycrystal cusps. Wear resistance was analyzed by measuring the vertical substance loss (mm) and the volume loss (mm(3)). Antagonist wear (mm) was also recorded. Data were statistically analyzed using one-way analysis of variance (ANOVA) (wear depth and volume loss) and Kruskal-Wallis one-way ANOVA on ranks (antagonist wear). Heat-cured HRi function and Aurocast8 showed similar mean values for wear depth and volumetric loss, and their results did not statistically differ in comparison with the human enamel.

The aim of this study was to assess the flexural strength, flexural elastic modulus and Vickers microhardness of three resin composites prepared at room temperature or cured after one or repeated preheating cycles to a temperature of 39°C. Three resin composites were evaluated: Enamel Plus HFO (Micerium), Opallis (FGM), and Ceram X Duo (Dentsply DeTrey). For each trial, one group of specimens of each material was fabricated under ambient laboratory conditions, whereas in the other groups, the composites were cured after 1, 10, 20, 30, or 40 preheating cycles to a temperature of 39°C in a preheating device. Ten rectangular prismatic specimens (25 × 2 × 2 mm) were prepared for each group (N=180; n=10) and subjected to a three-point bending test for flexural strength and flexural modulus evaluation. Vickers microhardness was assessed on 10 cylindrical specimens from each group (N=180; n=10). Statistical analysis showed that, regardless of the material, the number of heating cycles was not a significant factor and was unable to influence the three mechanical properties tested. However, a significant main effect of the employed material on the marginal means of the three dependent variables was detected.

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The preparation, cementation and finishing procedures are considered key factors for the long-term success of the indirect composite restorations.

The purpose of the present in vitro study was to compare the two-body wear resistance of a type 3 gold alloy (Aurocast8), two lithium disilicate glass ceramics (IPS e.max CAD and IPS e.max Press), a heat-pressed feldspathic porcelain (Cerabien ZR Press), an yttria-stabilized tetragonal zirconia polycrystal ceramic (Katana Zirconia ML), and three heat-cured composite resins (Ceram.X Universal, Enamel Plus Function, and Enamel Plus HRi) opposing antagonistic cusps made out of the same restorative materials. Ten 6-mm-thick samples and 10 cusp-shaped abraders were manufactured with each test material (n=10) according to standard laboratory procedures. All sample/antagonist pairs made out of the same material were subjected to a two-body wear test in a dual-axis chewing simulator for up to 120,000 loading cycles. The total vertical wear (mm) and the total volumetric loss (mm) for each sample/antagonist pair were calculated. Data were statistically analyzed using one-way analysis of variance tests. The total vertical wear for the gold alloy was not significantly different compared to Ceram.X Universal, Enamel Plus Function, IPS e.max CAD, and Cerabien ZR Press. Significantly increased wear values were observed for Enamel Plus HRi and IPS e.max Press. The lowest values for total vertical wear and volumetric loss were recorded on the monolithic zirconia.