ABSTRACT
Background: E-max is a more aesthetic material than traditional zirconia. In addition, the bond strength of traditional zirconia with adhesive cements is lower. There are not enough studies on how the aesthetic values and bond strength of 5-YZP, the new generation zirconia, compare to e-max and traditional zirconia. Can 5-YZP be an alternative to e-max in terms of aesthetics and bond strength? Aim: The aim of the study is to compare the translucency property and bonding ability of 5y-zp zirconias with previous generation zirconias and lithium disilicate. Materials and Methods: Two types of zirconia Katana UT and Katana HT for measuring translucency values; and using a type of lithium disilicate IPS e.max CAD LT, three groups were formed (n = 10). Translucency specimens were fabricated (n = 10). Their L*a*b* values were measured against a black-and-white background with a spectrophotometer, and DE00 was calculated. To perform micro-shear tests, a cylinder design was made from zirconia and IPS e.max CAD blocks (n = 20). After the samples were aged by thermal cycle, the micro-shear test was applied to specimens cemented to teeth extracted with two different adhesive cement systems. Results: According to the results of one-way analysis of variance, a statistically significant difference was found between the translucency parameter (TP) values of the groups. According to Tukey's honestly significant difference (HSD) multiple comparisons, the values of the three groups are statistically different from each other. Although IPS e.max CAD group has the highest TP values, the Katana HT group has the lowest values. Conclusion: 5Y-PZ has a TP intermediate to those of 3Y-TZP and lithium disilicate. Long-term bond strength of 3Y-TZP and 5Y-ZP were similar to those of lithium disilicate. To be an alternative to glass ceramics in the anterior region, translucency and bond strength values need to be improved.
Subject(s)
Zirconium , Humans , Aged , Materials Testing , Zirconium/chemistry , SpectrophotometryABSTRACT
INTRODUCTION: The resistance of three different substructure materials - metal (Cr-Co), zirconium (Zr), and ceramics (IPS Empress II) - was measured by sticking them to dentine with two different resin cements, a dual-cure resin cement (Panavia F 2.0 Light) and a self-adhesive resin cement (BisCem). MATERIALS AND METHODS: In an in vitro study, 72 central upper front teeth were selected with no decay or apparent breakage and with complete development, removed for periodontal reasons. Labial and incisal surfaces of all teeth were prepared. Molds were obtained to prepare metal (Co-Cr), Zr, and ceramic (IPS Empress II) blocks for use in the study. The compressive strengths of the obtained material infrastructures were examined after thermal cycle processing by performing cementation to the teeth with two different cements. The data obtained were analyzed statistically. The Mann-Whitney U-test was used for comparisons of the groups with two options, and Kruskal-Wallis variance analysis was used to compare more than two groups. P<0.05 were considered statistically significant. RESULTS: While the highest result between samples was 117.86 ± 47.94 N in the dual-cure (Panavia)-ceramic group, the lowest value was observed at 6.53 ± 3.12 N in the self-adhesive (BisCem)-metal group. There was a significant difference between dual-cure (Panavia) and self-adhesive (BisCem) groups. CONCLUSION: In this study, we measured the bond strength; our most durable resistance groups were found to be, in order, Panavia-ceramics >Panavia-metal >Panavia-Zr >self-adhesive-ceramics >self-adhesive-Zr >and self-adhesive-metal.
Subject(s)
Cementation/methods , Ceramics/standards , Dental Bonding/methods , Dental Cements/chemistry , Dental Porcelain , Resin Cements , Zirconium/standards , Ceramics/chemistry , Dental Stress Analysis , Dentin , Humans , Materials Testing , Resin Cements/chemistry , Surface Properties , Zirconium/chemistryABSTRACT
Labelled dentures can be important in identifying people who have lost their memory or in identifying the bodies of those who have died in disasters. Forensic dentistry has long considered marking dentures, although no standardised method has been developed. Of the many options considered, none maintain the marking after the dentures break or are altered in occurrences such as plane crashes, which can result in a marked increase in temperature. This study examined a ceramic marking system that can endure high temperatures and can also be used in fixed partial dentures.
Subject(s)
Denture Identification Marking/methods , Ceramics , Crowns , Denture, Complete , Denture, Partial, Fixed , Denture, Partial, Removable , Disasters , Electronic Data Processing , Forensic Dentistry , Humans , Patient Identification Systems/methodsABSTRACT
Alkaline protease was purified from Bacillus sp. isolated from soil. The pH optimum was 11.5 at 37 degrees C. Calcium divalent cation was effective to stabilize the enzyme especially at higher temperatures. The proteolytic activity was inhibited by active site inhibitors of PMSF (Phenylmethylsulfonyl fluoride), and ions of Mg, Mn, Pb, Li, Zn, Ag, Hg. The enzyme was stable in the presence of some detergents, such as Triton-X-100, Tween-80, SDS (sodium dodecyl sulfate) and EDTA (ethylendiaminetetraacetic acid), pH 11.5 and 37 degrees C for 30 min. The optimum pH was 11.5 at 37 degrees C and the optimum temperature was 62 degrees C at pH 11.5.
