scholarly journals Effect of Different Finishing and Polishing Methods for Color Stability of the E-Max Dental Ceramics: In vitro Study

2021 ◽  
Vol 14 (4) ◽  
pp. 1508-1513
Author(s):  
Ibraheem F Alshiddi

In order to assess the influence of finishing and polishing on the surface brightness and color stability of the ceramic veneer, fifty specimens were fabricated with 10 mm diameter and 2 mm thickness using IPS E-Max Ceramic. After glazing, 10 specimens were untouched as control group, and the other 40 specimens were abraded using 125µm diamond bur to create surface roughness. Forty specimens were divided into four groups (n=10), in group 1: specimens were finished using diamond point, in group 2 specimens’ surface was polished with a polishing kit, Group 3: Each specimen surface was polished with the polishing kit as in protocol 2 and was polished a polishing past and group 4 Each specimen was glazed by heating at 621℃ for 3 minutes followed by a temperature increase of 83℃/min up to 918℃ for 30 seconds. Color measurement was performed using spectrophotometer. Color stability data were analyzed using two-way ANOVA and Tukey’s HSD test (α=0.05). For Ra values, paired-samples t-tests were used to analyze the data and compare groups. The change in L and E showed a significant difference among the study groups; (group 1, group 2, group 3 and group 4) with respect to three variables L, a and b. A significant difference was noted when compared each group with the control; however, only group 2 showed a significant difference from group 4; the remaining groups demonstrated similar findings for all three variables. The study displayed a significant impact of the finishing and polishing technique on the surface brightness and color stability of ceramic restoration. However, it was evident that combination of two or three polishing techniques which includes polish kit and glaze enhances the surface finish and adds color stability by alternating the yellow – blue axis (increase in b) and red- green axis (decrease in a).

Author(s):  
Mine ARGALI DENIZ ◽  
Hilal ER ULUBABA ◽  
M. Furkan ARPACI ◽  
Fatih CAVUS ◽  
Gokhan DEMIRTAS ◽  
...  

Objective: In this study, the effect of tracheal diverticula (TD) on chest anthropometry and its relation with chronic obstructive pulmonary disease (COPD) was evaluated. Method: Between January 2019 and March 2020, 995 patients who underwent chest CT were retrospectively analyzed and TD was detected in 31 cases. Group 1 is only TD, Group 2 is TD + COPD, Group 3 is only COPD, Group 4 is defined as control group. We measured the localization, size, the distance to carina and vocal cord of TDs. In all groups chest diameters at T4 and T9 levels were measured as transverse and vertical plans. Results: TDs detected mostly at the T2 and T3 levels. In Group 1 and Group 2, there was a statistically significant difference the distance to TD of vocal chords. A statistically significant difference was found between Group 1 and Group 3 only in the vertical diameter at the T4 and T9 levels. Conclusion: We observed that COPD effect TD location and also TD had opposite effect on anteroposteriorly increasing chest parameters in COPD. Precence of TD is essential on COPD patients about thorax anthropometry. Keywords: Tracheal diverticulum; antropometry; radiology; COPD; chest diameter


2003 ◽  
Vol 17 (4) ◽  
pp. 337-341 ◽  
Author(s):  
Flávia Bittencourt Pazinatto ◽  
Bruno Barbosa Campos ◽  
Leonardo César Costa ◽  
Maria Teresa Atta

Thermocycling simulates, in vitro, thermal changes that occur in the oral cavity. The aim of this study was to evaluate the influence of the number of cycles on microleakage. Class V cavities (1.5 mm deep, 3 mm in height and 3 mm in width) were prepared in bovine teeth, restored with a Single Bond/Z250 restorative system (3M/ESPE) and then divided into five groups of ten teeth each: group 1 was not thermocycled (control group), and groups 2, 3, 4 and 5 were thermocycled 500, 1,000, 2,500 and 5,000 times, respectively (5º-55º ± 2ºC, 15 s dwell time). The teeth were immersed in 0.5% basic fuchsin aqueous solution for 24 h, sectioned and the sections with the highest degree of microleakage were selected, scanned and the extent of dye penetration was measured by the ImageTool program. The results submitted to one-way ANOVA showed no significant differences between the groups (p > 0.05). The averages of microleakage values in millimeters were: group 1 (3.92); group 2 (3.13); group 3 (4.48); group 4 (4.33) and group 5 (3.42). Thus, it was concluded that there is no relation between the increase of the number of cycles and the increase in microleakage.


2015 ◽  
Vol 63 (4) ◽  
pp. 426-431
Author(s):  
Ariani Rodrigues DIMER ◽  
Guilherme Anziliero AROSSI ◽  
Leonardo Haerter dos SANTOS ◽  
Diego Rafael KAPPAUN

Objective: To evaluate the influence of different additional polymerization methods on the microhardness of two direct composite resins. Methods: Direct Composite resins samples (Fill Magic and Opallis) and a Laboratory Composite Resin (Ceramage) were lightcured according to manufacturer instructions. Then, the direct resins were submitted to additional polymerization. Experimental groups were divided into (n = 5): group 1: Conventional Polymerization; group 2: Extra Light (80s); group 3: Autoclave; group 4: Laboratory Resin Ceramage. Vickers hardness test was carried out after a week of light-free storage in water, and results were subjected to ANOVA / Tukey statistical analysis. Results: Resin Lab Ceramage showed higher astatistically significant microhardness within all other resins in this study (p £ 0.05); Fill Magic showed no statistically significant difference between the groups tested compared to its control (p> 0.05); Opallis resin submitted to autoclave was the only method that showed a higher statistically significant difference compared to the control group (p £ 0.05). Conclusion: It concludes that hardness of a direct composite resin tested - Opallis - was increased by Autoclave post-cure polymerization, however, not enough to achieve the hardness of a laboratory composite. Furthermore, increasing lightcuring time does not produce a harder surface.


2007 ◽  
Vol 77 (5) ◽  
pp. 901-906 ◽  
Author(s):  
Tamer Turk ◽  
Selma Elekdag-Turk ◽  
Devrim Isci ◽  
Fethiye Cakmak ◽  
Nurhat Ozkalayci

Abstract Objective: To evaluate shear bond strengths (SBSs) of a self-etching primer (SEP) following saliva contamination at different stages of bonding at debond times of 5, 15, and 30 minutes and 24 hours. Materials and Methods: Two-hundred forty human premolars were divided into four groups: group 1, uncontaminated; group 2, saliva contamination after priming; group 3, saliva contamination before priming; and group 4, saliva contamination before and after priming. Four subgroups according to debond times of 5, 15, 30 minutes and 24 hours were composed. Metal brackets were bonded with an SEP (Transbond Plus) and light-cure adhesives paste (Transbond XT). SBS values and the adhesive remnants were determined. Results: The highest SBS was obtained at a debond time of 24 hours for the control group. This was significantly different from the other groups. SBSs at 5, 15, and 30 minutes showed no significant difference from each other in the control group (P > .05). Lowest SBSs were obtained at a debond time of 5 minutes for groups 1, 2, 3, and 4 (8.38, 7.10, 7.06, and 6.26 MPa, respectively) and were not significantly different from each other (P > .05). SBSs at 24 hours were not significantly different from each other for groups 2, 3, and 4 (P > .05). Significant differences were found in the adhesive remnant (P < .001). Conclusions: SEP (Transbond Plus) may produce clinically acceptable bracket bonding after 5, 15, and 30 minutes from time of placement on the teeth, even with light and heavy saliva contamination.


Author(s):  
R Piradhiba ◽  
Evan A Clement ◽  
Navaneetha Nambi ◽  
S Veerasankar ◽  
S Madhumitra ◽  
...  

Introduction: Orthodontic elastics are a very significant tool in orthodontics, as it is the most commonly used force delivering unit. Temperature plays a key role in the amount of force that elastics are able to produce. Hence, there is a need to evaluate the influence of storage temperature on the properties of orthodontic elastics before its clinical use. Aim: To evaluate the influence of different storage temperature of latex orthodontic elastics. Materials and Methods: This cross-sectional study was conducted at Sathyabama Dental College and Hospital, Chennai, in November 2019. Sample of 40 latex orthodontic elastics (TP Orthodontics, medium force, standard size of 3/16′′) were divided into four groups with 10 elastics each, based on their storage temperature and stored in closed plastic packages. Group 1 was kept as a Control group and Group 2, Group 3 and Group 4 were stored in three Incubators under the specified storage temperatures such as 26-28°C, 4-8°C, 37°C respectively. The elastics were stretched and their forces measured in six progressive increases of 100% of their inner diameter, starting at a level of 100% stretching, with the Universal Testing Machine, Instron. The samples were also tested for Maximum Stress (MPa), Maximum Force (N), Maximum Elongation (%) and Break Distance (mm). Data were analysed using Statistical Package for the Social Science (SPSS) software version 16.0, one-way Analysis of Variance (ANOVA) and post-hoc test. Results: On evaluating the stress at 100%, 200%, 300%, 400%, 500%, 600% of strain, there was no statistically significant difference between the groups. Maximum Stress MPa was found to be 24.12±3.32, 25.12±3.42, 23.3±3.41, 23.97±3.50 for group1, group 2, group 3 and group 4 respectively. Maximum Elongation (%) was found to be 1369.0±25.108, 1364.0±23.190, 1359.0±35.103, 1363.0±34.657 for group 1, group 2, group 3 and group 4, respectively. Break Distance (mm) was found to be 68.48±1.267, 68.28±1.267, 67.87±1.77 and 68.19±1.727 for group1, group 2, group 3 and group 4, respectively. And none of the parameters tested showed statistical significance between the four groups. Conclusion: Latex elastics may be stored under any of the conditions tested in the present study over a period of one month, since different storage temperatures over a period of one month did not interfere in their mechanical properties.


2008 ◽  
Vol 9 (7) ◽  
pp. 65-72 ◽  
Author(s):  
Emre Ozel ◽  
Yonca Korkmaz ◽  
Nuray Attar

Abstract Aim The aim of this in vitro study was to investigate the cervical microleakage and internal voids of nanocomposites comparing them with a hybrid composite in Class II restorations with the margins located coronal and apical to the cementoenamel junction (CEJ). Methods and Materials Standardized MOD cavities (one cervical margin located in dentin, one in enamel) were prepared in 40 extracted human molars and divided into four groups according to the composite used to restore them (n=10/group). Group 1: Adper Single Bond2/Filtek Supreme XT; Group 2: Excite/Tetric EvoCeram; Group 3: Prime & BondNT/Ceram X; and Group 4 (control) Adper Single Bond2/Filtek Z250. Groups were further divided into subgroups A and B. The “A” subgroups represent the level of the location of the cervial margin at 1 mm coronal to the CEJ, and the “B” subgroups represent the level of the cervical margin located 1 mm apical to the CEJ. After restoration of the cavities with nanocomposites, thermocycling, and immersion in 0.5% basic fuchsin, the dye penetration and internal voids were evaluated under a stereomicroscope. Data were analyzed with the Mann-Whitney U and Kruskal-Wallis tests with the Bonferroni correction for microleakage and with the Chi-square test for internal voids (p<0.05). Results The microleakage in the A subgroups was statistically significantly lower then B subgroups (p<0.05). No statistically significant difference was observed in terms of interface, cervical, and occlusal voids for all groups (p>0.05). No significant difference was observed between each group for three voids in all groups (p>0.05). Conclusion The location of the gingival margin affects the microleakage of nanocomposites but has no significant affect on the internal voids. Clinical Significance Gingival margin located 1 mm coronal to the CEJ provided a reduction in cervical microleakage in nanocomposite restorations. Citation Ozel E, Korkmaz Y, Attar N. Influence of Location of the Gingival Margin on the Microleakage and Internal Voids of Nanocomposites. J Contemp Dent Pract 2008 November; (9)7:065-072.


2015 ◽  
Vol 03 (02) ◽  
pp. 103-111
Author(s):  
Jaidev Dhillon ◽  
Sachin Passi ◽  
Ajay Chhabra ◽  
◽  

Abstract Objective: To compare and evaluate the fracture resistance of endodontically treated molars reinforced with various bonded restorations and to study the type of fractures in various restorations. Methods: Forty extracted mandibular molars were endodontically treated. MOD (Mesio-Occluso-Distal) cavities were prepared and Mesio-Buccal cusp was reduced in all to provide cuspal coverage. All the teeth were then divided into 4 groups. The cavities in group 1(control) were filled with high copper amalgam. Group 2 was restored with direct resin composite. In group 3 after the priming and bonding procedures as in group 2, cavity surfaces were coated with flowable resin composite. Before curing a piece of polyethylene ribbon fiber was cut and coated with adhesive resin and was embedded inside the flowable composite. The resin composite was cured with visible light cure (VLC) gun. For group 4, restorations were done according to the recommendations provided by the manufacturers of SR Adoro (Ivoclar-Vivadent, Schaan, Liechtenstein) composite material. Compressive fracture strength test was performed after at least 24 hours of the fabrication of the specimens, by application of compressive loading in a Universal testing machine, applied on the occlusal aspect of each specimen with a steel bar. The mean loads necessary to fracture were recorded in Newton and the results were statistically analyzed. Results: Group 4 (indirect composite inlay) had the greater fracture resistance and group 1(Amalgam) had the poorest. Difference between group 1 and 3, group 1 and 4, group 2 and 4 were statistically significant. No statistically significant difference was found between group 1 and 2, group 2 and 3, group 3 and 4. Predominant type of fracture in group 1 and 3 was fracture of tooth below cemento enamel junction at tooth restoration interface without mesio buccal cusp involvement. In group 2 and 4, predominant fractures were of tooth below cemento enamel junction through center of restoration without mesio–buccal cusp involvement.


1993 ◽  
Vol 21 (2) ◽  
pp. 201-203 ◽  
Author(s):  
M. M. McSwiney ◽  
G. P. Joshi ◽  
P. Kenny ◽  
S. M. McCarroll

In a double-blind, randomised controlled trial, we studied 40 patients who received one of four intra-articular injections at the end of arthroscopic surgery. Each group contained ten patients. The patients in Group 1 received normal saline 25 ml; those in Group 2 received bupivacaine 0.25% 25 ml; those in Group 3 received morphine 5 mg in normal saline 25 ml; and those in Group 4 received a combination of bupivacaine 0.5% 12.5 ml and 5 mg of morphine made up to 25 ml with normal saline to produce the same bupivacaine concentration as Group 2. At the time the patient awoke, and 30min, Ihr, Ihr 30min, 2hr, 4hr, 8hr, 12hr, and 24hr postoperatively, pain was assessed using a visual analogue scale. The need for supplementary analgesic agents in the first 24 hours was recorded. All pain scores were significantly lower (P< 0.05) in Groups 2, 3 and 4 compared with the control group with the exception of Group 2 at 24 hours. Pain scores were significantly lower (P<0.05) for Group 2 compared with Group 3 for the first 90 minutes postoperatively. At 4, 8, 12 and 24 hours postoperatively the pain scores were significantly lower (P<0.05%) for Group 3 compared with Group 2. Group 4 had the lowest pain scores over the recorded period compared with the other groups. The need for supplemental analgesia was significantly lower (P<0.05) in the treatment Groups 2, 3 and 4 compared to the control Group 1. There was no significant difference in supplemental analgesic requirements between Groups 2, 3 and 4. A combination of bupivacaine and morphine injected intra-articularly following arthroscopy provided superior analgesia compared with that achieved by either drug alone.


VASA ◽  
2020 ◽  
Vol 49 (4) ◽  
pp. 281-284
Author(s):  
Atıf Yolgosteren ◽  
Gencehan Kumtepe ◽  
Melda Payaslioglu ◽  
Cuneyt Ozakin

Summary. Background: Prosthetic vascular graft infection (PVGI) is a complication with high mortality. Cyanoacrylate (CA) is an adhesive which has been used in a number of surgical procedures. In this in-vivo study, we aimed to evaluate the relationship between PVGI and CA. Materials and methods: Thirty-two rats were equally divided into four groups. Pouch was formed on back of rats until deep fascia. In group 1, vascular graft with polyethyleneterephthalate (PET) was placed into pouch. In group 2, MRSA strain with a density of 1 ml 0.5 MacFarland was injected into pouch. In group 3, 1 cm 2 vascular graft with PET piece was placed into pouch and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. In group 4, 1 cm 2 vascular graft with PET piece impregnated with N-butyl cyanoacrylate-based adhesive was placed and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. All rats were scarified in 96th hour, culture samples were taken where intervention was performed and were evaluated microbiologically. Bacteria reproducing in each group were numerically evaluated based on colony-forming unit (CFU/ml) and compared by taking their average. Results: MRSA reproduction of 0 CFU/ml in group 1, of 1410 CFU/ml in group 2, of 180 200 CFU/ml in group 3 and of 625 300 CFU/ml in group 4 was present. A statistically significant difference was present between group 1 and group 4 (p < 0.01), between group 2 and group 4 (p < 0.01), between group 3 and group 4 (p < 0.05). In terms of reproduction, no statistically significant difference was found in group 1, group 2, group 3 in themselves. Conclusions: We observed that the rate of infection increased in the cyanoacyrylate group where cyanoacrylate was used. We think that surgeon should be more careful in using CA in vascular surgery.


2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 340.2-341
Author(s):  
V. Orefice ◽  
F. Ceccarelli ◽  
C. Barbati ◽  
R. Lucchetti ◽  
G. Olivieri ◽  
...  

Background:Systemic lupus erythematosus (SLE) is an autoimmune disease mainly affecting women of childbearing age. The interplay between genetic and environmental factors may contribute to disease pathogenesis1. At today, no robust data are available about the possible contribute of diet in SLE. Caffeine, one of the most widely consumed products in the world, seems to interact with multiple components of the immune system by acting as a non-specific phosphodiesterase inhibitor2.In vitrodose-dependent treatment with caffeine seems to down-regulate mRNA levels of key inflammation-related genes and similarly reduce levels of different pro-inflammatory cytokines3.Objectives:We evaluated the impact of caffeine consumption on SLE-related disease phenotype and activity, in terms of clinimetric assessment and cytokines levels.Methods:We performed a cross-sectional study, enrolling consecutive patients and reporting their clinical and laboratory data. Disease activity was assessed by SLE Disease Activity Index 2000 (SLEDAI-2k)4. Caffeine intake was evaluated by a 7-day food frequency questionnaire, including all the main sources of caffeine. As previously reported, patients were divided in four groups according to the daily caffeine intake: <29.1 mg/day (group 1), 29.2-153.7 mg/day (group 2), 153.8-376.5 mg/day (group 3) and >376.6 mg/day (group 4)5. At the end of questionnaire filling, blood samples were collected from each patient to assess cytokines levels. These were assessed by using a panel by Bio-Plex assays to measure the levels of IL-6, IL-10, IL-17, IL-27, IFN-γ, IFN-α and Blys.Results:We enrolled 89 SLE patients (F/M 87/2, median age 46 years, IQR 14; median disease duration 144 months, IQR 150). The median intake of caffeine was 195 mg/day (IQR 160.5). At the time of the enrollment, 8 patients (8.9%) referred a caffeine intake < 29.1 mg/day (group 1), 27 patients (30.3%) between 29.2 and 153.7 mg/day (group 2), 45 patients (51%) between 153.8 and 376.5 mg/day (group 3) and 9 patients (10.1%) >376.6 mg/day (group 4). A negative correlation between the levels of caffeine and disease activity, evaluated with SLEDAI-2K, was observed (p=0.01, r=-0.26). By comparing the four groups, a significant higher prevalence of lupus nephritis, neuropsychiatric involvement, haematological manifestations, hypocomplementemia and anti-dsDNA positivity was observed in patients with less intake of caffeine (figure 1 A-E). Furthermore, patients with less intake of caffeine showed a significant more frequent use of glucocorticoids [group 4: 22.2%,versusgroup 1 (50.0%, p=0.0001), group 2 (55.5%, p=0.0001), group 3 (40.0%, p=0.009)]. Moving on cytokines analysis, a negative correlation between daily caffeine consumption and serum level of IFNγ was found (p=0.03, r=-0.2) (figure 2A); furthermore, patients with more caffeine intake showed significant lower levels of IFNα (p=0.02, figure 2B), IL-17 (p=0.01, figure 2C) and IL-6 (p=0.003, figure 2D).Conclusion:This is the first report demonstrating the impact of caffeine on SLE disease activity status, as demonstrated by the inverse correlation between its intake and both SLEDAI-2k values and cytokines levels. Moreover, in our cohort, patients with less caffeine consumption seems to have a more severe disease phenotype, especially in terms of renal and neuropsychiatric involvement. Our results seem to suggest a possible immunoregulatory dose-dependent effect of caffeine, through the modulation of serum cytokine levels, as already suggested byin vitroanalysis.References:[1]Kaul et alNat. Rev. Dis. Prim.2016; 2. Aronsen et alEurop Joul of Pharm2014; 3. Iris et alClin Immun.2018; 4. Gladman et al J Rheumatol. 2002; 5. Mikuls et alArth Rheum2002Disclosure of Interests:Valeria Orefice: None declared, Fulvia Ceccarelli: None declared, cristiana barbati: None declared, Ramona Lucchetti: None declared, Giulio Olivieri: None declared, enrica cipriano: None declared, Francesco Natalucci: None declared, Carlo Perricone: None declared, Francesca Romana Spinelli Grant/research support from: Pfizer, Consultant of: Novartis, Gilead, Lilly, Sanofi, Celgene, Speakers bureau: Lilly, cristiano alessandri Grant/research support from: Pfizer, Guido Valesini: None declared, Fabrizio Conti Speakers bureau: BMS, Lilly, Abbvie, Pfizer, Sanofi


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