Three-body wear potential of dental yttrium-stabilized zirconia ceramic after grinding, polishing, and glazing treatments (original) (raw)
Related papers
Original study, 2017
Purpose: The purpose of this in vitro research project was to evaluate and compare the wear behavior of human tooth enamel opposing monolithic zirconia and other different ceramic restorative materials and also to observe the tetragonal to monoclinic phase transformation in zirconia‑based ceramics that may occur while simulating wear occurring at room temperature in a wet environment. Materials and Methods: A total of sixty samples were prepared for this study. Fifteen discs of glazed zirconia, 15 discs of polished zirconia without glaze, 15 discs of metal ceramic, and 15 discs of lithium disilicate were fabricated. Sixty extracted premolars were collected and randomly divided into four groups of 15 each. The discs and extracted human premolars were placed onto holders on a two‑body wear machine under a constant load of 5 kg to simulate the oral wear cycle. A diffractometer was used to analyze phase transformation. One‑way analysis of variance and Tukey’s post hoc tests was used. Results: The mean loss of height of tooth samples and its standard deviation for Group I (monolithic zirconia with glaze), Group II (mechanically polished monolithic zirconia without glaze), Group III (porcelain fused to metal), and Group IV (glazed monolithic lithium disilicate) was obtained as 0.2716 ± 0.1409, 0.1240 ± 0.0625, 0.1567 ± 0.0996, and 0.2377 ± 0.1350, respectively. The highest mean loss in height was observed in Group I and the least was observed in Group II. Conclusion: Mechanically polished zirconia showed the least amount of enamel wear followed by porcelain fused to metal and glazed monolithic lithium disilicate, whereas glazed monolithic zirconia showed the highest enamel wear.
Comparison of the Effect of Feldspathic Porcelain and Zirconia on Natural Tooth Wear
2014
Background and Aim: Enamel wear is among the main disadvantages of ceramic restorations. Recently, use of full zirconia crowns without dental porcelain has been suggested. The aim of this study was to compare the effect of feldspathic porcelain and zirconia on the wear of natural teeth. Materials and Methods: In this experimental study, 22 zirconia specimens were fabricated; out of which, 11 specimens were polished and chosen as zirconia specimens while the remaining 11 were used to fabricate porcelain specimens. A total of 22 natural human teeth were also obtained. The natural teeth were photographed by a stereomicroscope in a fixed position and the distance from the cusp tip to a reference point was measured. Next, 11 teeth opposed zirconia and the remaining 11 opposed porcelain specimens in a chewing simulator and subjected to 120,000 masticatory cycles. The teeth were photographed again and the greatest difference between the before and after values was recorded. Results: The me...
Brazilian Dental Science, 2020
Objective: To evaluate and compare the wear behavior of three different ceramic systems; monolithic zirconia, lithium di-silicate and nano-fluorapatite glass ceramic with two finishing procedures polishing and glazing, and their effect on the wear of natural tooth antagonists. Material and Methods: Forty two ceramic disc specimens (10mm x3mm) and forty two natural tooth antagonists were used. Samples were divided according to ceramic materials into 3 groups (n = 14). Group I: nano-fluorapatite glass ceramic (FLU) (IPS e.max Ceram), Group II: lithium disilicate (LD) (IPS e.max CAD) and group III: monolithic zirconia (ZIR) (ZirkoZahn Prettau). Each group was further subdivided into two subgroups (n = 7), according to the surface finish: Polishing (P) and glazing (G). Specimens were subjected to a custom designed two-body wear simulator. Quantitative wear assessment was carried out using weight loss measurements. Scanning electron microscope was used for characterization of wear patterns. Kruscal Wallis and Dunn's tests were used to compare between weight loss of the three ceramic materials. Whitney U test was used to compare the weight loss between the two surface finish protocols. Wilcoxon Signed rank test was used to compare the weight loss between ceramic specimens and antagonist teeth (p ≤ 0.05). Paired t-test was used to compare weight loss before and after wear test. Results: After wear, LD and FLU had the highest weight loss values compared to ZIR (p < 0.05). For teeth, there was no significant difference between the weight loss values with the three materials (p > 0.05). P and G specimens showed no significant difference in weight loss values. SEM images of the wear patterns verified the previous analysis. Conclusion: ZIR is more wear resistant than LD and FLU. However, the surface treatment had no impact on the wear behavior. Comportamento do desgaste da zircônia monolítica frente a dentes naturais em comparação com duas cerâmicas de vidro com diferentes protocolos de acabamento superficial: um estudo in vitro
A study on the in-vitro wear of the natural tooth structure by opposing zirconia or dental porcelain
2010
PURPOSE. This study was conducted to evaluate clinical validity of a zirconia full-coverage crown by comparing zirconia' s wear capacity over antagonistic teeth with that of feldspathic dental porcelain. MATERIALS AND METHODS. The subject groups were divided into three groups: the polished feldspathic dental porcelain group (Group 1), the polished zirconia group (Group 2), and the polished zirconia with glazing group (Group 3). Twenty specimens were prepared from each group. Each procedure such as plasticity, condensation, and glazing was conducted according to the manufacturer' s manual. A wear test was conducted with 240,000 chewing cycles using a dual-axis chewing simulator. The degree of wear of the antagonistic teeth was calculated by measuring the volume loss using a three-dimensional profiling system and ANSUR 3D software. The statistical significance of the measured degree of wear was tested with a significant level of 5% using one-way ANOVA and the Tukey test. RESULTS. The degrees of wear of the antagonistic teeth were 0.119 ± 0.059 mm 3 in Group 1, 0.078 ± 0.063 mm 3 in Group 3, and 0.031 ± 0.033 mm 3 in Group 2. Statistical significance was found between Group 1 and Groups 2 and between Group 2 and 3, whereas no statistical significance was found between Group 1 and Group 3. CONCLUSION. Despite the limitations of this study on the evaluation of antagonistic teeth wear, the degree of antagonistic tooth wear was less in zirconia than feldspathic dental porcelain, representing that the zirconia may be more beneficial in terms of antagonistic tooth wear. [
The International Journal of Prosthodontics, 2021
To evaluate and compare the wear of natural enamel against metal-ceramic and monolithic zirconia crowns, with the null hypothesis that there would be no difference in wear between metal-ceramic and monolithic zirconia. Materials and Methods: In 30 subjects within the age range of 18 to 40 years, two bilaterally opposing molars (maxillary/mandibular) were prepared to receive a monolithic zirconia crown or a metal-ceramic crown with feldspathic porcelain veneer. A polyvinyl siloxane impression of the opposing arch was taken at the time of cementation and 1 year after cementation. Casts were poured in type III gypsum and scanned, and the images were superimposed onto each other. AutoCAD was used to calculate the difference between the two images, which corresponded to the linear wear of the antagonist teeth. Statistical analysis of the data was done using one-way analysis of variance (ANOVA) and post hoc Tukey honest significant difference test for intergroup comparison. The P value obtained by one-way ANOVA was 1.1102e-16 (< .05), and by post hoc Tukey test was .001. Results: The mean wear of enamel against enamel was 14.8 ± 1.3 μm; of enamel against metal-ceramic was 87.1 ± 18.3 μm; and of enamel against monolithic zirconia was 59.4 ± 13.6 μm. The P values obtained indicated that the difference in wear of the antagonist tooth between monolithic zirconia and metal-ceramic was significant. Conclusion: It can be concluded that monolithic zirconia causes less wear of antagonist teeth than metal-ceramic veneered with feldspathic porcelain.
The wear of polished and glazed zirconia against enamel
The Journal of Prosthetic Dentistry, 2013
Polished zirconia is more wear friendly to opposing enamel than veneering porcelain. Therefore, polished anatomically contoured zirconia restorations can be indicated in high load bearing areas. The glazing of crowns should be avoided unless there is a high esthetic demand. In these situations, zirconia should be polished and then reglazed. Statement of problem. The wear of tooth structure opposing anatomically contoured zirconia crowns requires further investigation. Purpose. The purpose of this in vitro study was to measure the roughness and wear of polished, glazed, and polished then reglazed zirconia against human enamel antagonists and compare the measurements to those of veneering porcelain and natural enamel. Material and methods. Zirconia specimens were divided into polished, glazed, and polished then reglazed groups (n=8). A veneering porcelain (Ceramco3) and enamel were used as controls. The surface roughness of all pretest specimens was measured. Wear testing was performed in the newly designed Alabama wear testing device. The mesiobuccal cusps of extracted molars were standardized and used as antagonists. Three-dimensional (3D) scans of the specimens and antagonists were obtained at baseline and after 200 000 and 400 000 cycles with a profilometer. The baseline scans were superimposed on the posttesting scans to determine volumetric wear. Data were analyzed with a 1-way ANOVA and Tukey Honestly Significant Difference (HSD) post hoc tests (_=.05) Results. Surface roughness ranked in order of least rough to roughest was: polished zirconia, glazed zirconia, polished then reglazed zirconia, veneering porcelain, and enamel. For ceramic, there was no measureable loss on polished zirconia, moderate loss on the surface of enamel, and significant loss on glazed and polished then reglazed zirconia. The highest ceramic wear was exhibited by the veneering ceramic. For enamel antagonists, polished zirconia caused the least wear, and enamel caused moderate wear. Glazed and polished then reglazed zirconia showed significant opposing enamel wear, and veneering porcelain demonstrated the most. Conclusions. Within the limitations of the study, polished zirconia is wear-friendly to the opposing tooth. Glazed zirconia causes more material and antagonist wear than polished zirconia. The surface roughness of the zirconia aided in predicting the wear of the opposing dentition.
Randomized clinical study of wear of enamel antagonists against polished monolithic zirconia crowns
Journal of Dentistry, 2018
Objectives: To test the hypothesis that there is no difference in the in vivo maximum wear of enamel opposing monolithic zirconia crowns, enamel opposing porcelain fused to metal crowns and enamel opposing enamel. Methods: Thirty patients needing single crowns were randomized to receive either a monolithic zirconia or metal-ceramic crown. Two non-restored opposing teeth in the same quadrants were identified to serve as enamel controls. After cementation, quadrants were scanned for baseline data. Polyvinylsiloxane impressions were obtained and poured in white stone. Patients were recalled at six-months and one-year for re-impression. Stone models were scanned using a tabletop laserscanner to determine maximum wear. Statistical analysis was performed using Mann-Whitney U to determine any significant differences between the wear of enamel against zirconia and metal-ceramic crowns. Results: Sixteen zirconia and 14 metal-ceramic crowns were delivered. There were no statistical differences in mean wear of crown types (p = 0.165); enamel antagonists (p = 0.235) and enamel controls (p = 0.843) after one year. Conclusion: Monolithic zirconia exhibited comparable wear of enamel compared with metal-ceramic crowns and control enamel after one year. Significance: This study is clinically significant because the use of polished monolithic zirconia demonstrated comparable wear of opposing enamel to metal-ceramic and enamel antagonists.
Dental Materials, 2018
Objective. To evaluate the effect of different pH media on zirconia-reinforced lithium silicate glass ceramic and how they interact with opposing dentition after being aged in different pH cycling and high temperature conditions. Methods. Twenty-five rectangular shaped specimens were prepared from lithium silicate reinforced with zirconia blanks (Suprinity, Vita Zahnfabrick) and stored in different pH media (3 & 7.2) for different periods (24 h & 7 days) at temperature (55 • C). After their surface roughness (Ra) evaluation, aged ceramic specimens were subjected to cyclic abrasive wear with opposing natural teeth enamel for 150,000 cycles using a chewing simulator. Weight loss and Scanning Electron Microscope (SEM) images were used to evaluate the cyclic wear results. Results. After different pH storage, ceramic group stored at 3 pH for 1-W (1 week) gave significantly higher mean Ra value (0.618 m ± 0.117) than control lowest mean value (0.357 m ± 0.054) before cyclic wear. On the other hand, it caused the least significant weight loss value (0.004 gm ± 0.001) to opposing tooth enamel. There was significant tooth enamel weight loss (0.043 gm ± 0.004) when opposed with ceramic group stored in 3 pH media for 24 h (24-H). Their SEM images showed a prominent wear scar on enamel cusp tip. There was a significant increase in surface roughness Ra of ceramic material after abrasive cyclic wear. Significance. Great attention should be paid to Ra of this type of glass ceramic even if it is considered as minimal values. It can induce a significant amount of enamel tooth wear after a period equivalent to one year of intra-oral function rather than the significantly higher surface Ra of such ceramic type can do.
Objective. This study tested whether the two-body wear of monolithic zirconia and their corresponding enamel antagonists was higher compared to monolithic alloy and veneered zirconia. Materials and methods. Cylindrical specimens (N = 36, n = 6) were prepared out of (A) veneered zirconia (VZ), (B) glazed zirconia using a glaze ceramic (GZC), (C) glazed zirconia using a glaze spray (GZS), (D) manually polished monolithic zirconia (MAZ), (E) mechanically polished monolithic zirconia (MEZ) and (F) monolithic base alloy (control group, MA). Wear tests were performed in a chewing simulator (49 N, 1.7 Hz, 5 C/50 C) with enamel antagonists. The wear analysis was performed using a 3D profilometer before and after 120,000, 240,000, 640,000 and 1,200,000 masticatory cycles. SEM images were used for evaluating wear qualitatively. The longitudinal results were analysed using linear mixed models (a = 0.05). Results. Materials (p < 0.001) and number of masticatory cycles (p < 0.001) had a significant effect on the wear level. The least enamel antagonist wear was observed for MAZ and MEZ (27.3 ± 15.2, 28 ± 11.1 mm, respectively). GZC (118 ± 30.9 mm) showed the highest wear of enamel antagonists. The highest wear rate in the material was observed in GZS (91.3 ± 38.6 mm). While in the groups of MA, VZ, GZC and GZS 50% of the specimens developed cracks in enamel, it was 100% in MAZ and MEZ groups. Conclusion. Polished monolithic zirconia showed lower wear rate on enamel antagonists as well as within the material itself but developed higher rates of enamel cracks.