title: Marginal, internal fit and microleakage of zirconia infrastructures: an in-vitro study.
abstract: This in-vitro study compared the marginal and internal fit and also the microleakage of zirconia infrastructures (Procera All-Zircon, Cercon Smart Ceramics) in contrast to heat-pressed ones (Empress 2).Thirty maxillary premolars (n=30) were divided into three groups (n=10) and prepared with individual chamfer preparations by using the silicone index method. Plaster dies of 10 individual preparations were allocated to each coping fabrication method of computer-aided design and computer-aided manufacturing (Procera), computer-aided manufacturing (Cercon) and heat pressing (Empress 2) as the control. All the specimens were kept in distilled water at room temperature for four weeks after cementation with dual-curing resin cement (Variolink II, Ivoclar-Vivadent). They were then thermocycled between 5°C to 55°C for 5000 cycles with a 20-second dwell time and immersed in 0.5% basic fuchsin for 48 hours. The cemented specimens were separated into two halves vertically in the midvestibulo-palatal direction. The specimens were examined under a computer-aided stereomicroscope to evaluate both the internal and marginal fit. Marginal and internal gap widths were measured at 100× magnification. The specimens were evaluated for microleakage under a stereomicroscope at 100 × magnification. Selected specimens from each group were also examined using a scanning electron microscope. Fitting accuracy data were analyzed statistically with the Welch test and the Post-hoc Dunnett C-test (p<0.05). The microleakage data were analyzed with the Kruskal-Wallis test. Special software (SPSS/PC+ Version 10.0, SPSS, Chicago, IL, USA) was used for statistical evaluations.Differences between the marginal and internal fitting accuracy of the tested non-veneered infrastructures were found to be statistically significant (p<0.05). However, there were no significant differences in microleakage among the groups (p=0.273).
authors.forename: L
authors.initials: L
authors.lastname: Korkut
authors.forename: H S
authors.initials: HS
authors.lastname: Cotert
authors.forename: H
authors.initials: H
authors.lastname: Kurtulmus
mesh_terms: D001641:Bicuspid; D016009:Chi-Square Distribution; D017076:Computer-Aided Design; D003442:Crowns; D003763:Dental Leakage / Q000517:prevention & control*; D018772:Dental Marginal Adaptation; D003776:Dental Porcelain; D017267:Dental Prosthesis Design / Q000379:methods*; D006358:Hot Temperature; D006801:Humans; D017755:Prosthesis Fitting; D018709:Statistics, Nonparametric; D019231:Tooth Preparation, Prosthodontic
chemical_list: D003776:Dental Porcelain