scholarly journals Analysis of the surface of healthy and fluorotic human enamel using microhardness test

2017 ◽  
Vol 30 (1) ◽  
pp. 6-9
Author(s):  
Ana Josefina Monjarás Ávila ◽  
Veronica Zavala Alonso ◽  
Grace Morales Alcocer ◽  
Gabriel Alejandro Martínez Castañón ◽  
Nuria Patiño Marín ◽  
...  
Keyword(s):  
Tooth Enamel ◽  
Dental Fluorosis ◽  
Essential Property ◽  
Surface Microhardness ◽  
Average Standard Deviation ◽  
Mean Values ◽  
Hardness Tester ◽  
Tukey Test ◽  
Human Enamel ◽  
The Mean

The microhardness is an essential property of tooth enamel; there may be many factors that alter or diminish this quality causing weakness, one of which is dental fluorosis. The aim of this study was evaluate the surface microhardness of fluorotic enamel compared with healthy enamel. Two hundred forty extracted human molars were classified into four groups: Healthy (H), mild (MI), moderate (MO) and severe (S) fluorosis according to the Dean index. All samples were analyzed by Micro Vickers Hardness Tester. Average, standard deviation and ranges were calculated for quantitative variables, the ANOVA and Tukey test was used to identify differences between groups. The mean values of surface microhardness in HVN were: H, 333.4; MI, 290.3; MO, 266.1; S, 252.0. The differences between mean surface microhardness among healthy group and fluorotic groups were statistically significant (p

scholarly journals pH of exudate test in the physiological quality of crambe seeds

2016 ◽  
Vol 46 (6) ◽  
pp. 1014-1018 ◽  
Author(s):  
Charline Zaratin Alves ◽  
Lennis Afraire Rodrigues ◽  
Carlos Henrique Queiroz Rego ◽  
Josué Bispo da Silva
Keyword(s):  
Pearson Correlation ◽  
Raw Material ◽  
Mean Values ◽  
Tukey Test ◽  
Physiological Quality ◽  
The Subject ◽  
The Mean ◽  
C 30

ABSTRACT: Crambe is a rapeseed with high oil content and can be used as a winter cover or as a source of raw material for the production of biodiesel, however espite the growing interest in the culture, research on the subject is still incipient, especially concerning the seed production and analysis technology. The purpose of this study is to evaluate the physiological quality of crambe seeds, 'FMS Brilhante' cultivar, by testing the pH of exudate. Five seed lots were submitted to the determination of water content and the tests of germination and vigor (first count, emergence and tetrazolium). In the conduction of pH exudate test, temperatures (25 and 30oC), and periods of seed imbibition in water (15, 30 and 45 minutes) were tested. The experiment was conducted in a completely randomized manner, with four replicates, and the mean values were compared by the Tukey test at 5% probability; Pearson correlation between the pH of the exudate and initial tests was also made. Testing the pH of exudate is promising for separating lots of crambe seeds and the following combinations of 25°C/30 minutes or 30°C/45 minutes can be used.

scholarly journals Comparison of Shade of Ceramic with Three Different Zirconia Substructures using Spectrophotometer

2015 ◽  
Vol 16 (2) ◽  
pp. 135-140 ◽  
Author(s):  
Syed Rashid Habib ◽  
Ibraheem F Al Shiddi
Keyword(s):  
Maximum Difference ◽  
Mean Values ◽  
Tukey Test ◽  
Ceramic Color ◽  
Significant Difference ◽  
Grand Rapids ◽  
All Ceramic ◽  
The Mean ◽  
Type 3

ABSTRACT Objective This study assessed how changing the Zirconia (Zr) substructure affected the color samples after they have been overlaid by the same shade of veneering ceramic. Materials and methods Three commercial Zr materials were tested in this study: Prettau® Zirconia (ZirKonZahn, Italy), Cercon (Dentsply, Germany) and InCoris ZI (Sirona, Germany). For each system, 15 disk-shaped specimens (10 × 1 mm) were fabricated. Three shades of A1, A2 and A3.5 of porcelain (IPS e.MaxCeram, IvoclarVivadent, USA) were used for layering the specimens. Five specimens from each type of Zr were layered with same shade of ceramic. Color measurements were recorderd by a spectrophotometer Color-Eye® 7000A (X-Rite, Grand Rapids, MI). Mean values of L, a, b color coordinates and ?E were recorded and comparisons were made. Results Differences in the ΔE were recorded for the same porcelain shade with different Zr substructures and affected the color of the specimens (p < 0.01, ANOVA). The maximum difference between the ΔE values for the A1, A2 and A3.5 shades with three types of Zr substructures was found to be 1.59, 1.69 and 1.45 respectively. Multiple comparisons of the ΔE with PostHoc Tukey test revealed a statistically significant difference (p < 0.05) between the three types of Zr, except between Type 2 Zr and Type 3 Zr for the Shade A1. The mean values of L, a, b and ΔE for the Prettau® Zirconia substructure were found to be the least among the three types. Conclusions The brand of Zr used influences the final color of the all ceramic Zr based restorations and this has clinical significance. How to cite this article Habib SR, Al Shiddi IF. Comparison of Shade of Ceramic with Three Different Zirconia Substructures using Spectrophotometer. J Contemp Dent Pract 2015;16(2): 135-140.

scholarly journals EROSIVE POTENTIAL OF SPORTS BEVERAGES ON HUMAN ENAMEL “IN VITRO”

2018 ◽  
Vol 24 (5) ◽  
pp. 386-390
Author(s):  
Dalila Meazza Damo ◽  
Guilherme Anziliero Arossi ◽  
Helena Alvez da Silva ◽  
Leonardo Haerter dos Santos ◽  
Diego Rafael Kappaun
Keyword(s):  
Vickers Microhardness ◽  
Tooth Enamel ◽  
Low Ph ◽  
Control Surface ◽  
Test Surface ◽  
Results Of Treatment ◽  
Sports Drinks ◽  
Human Enamel ◽  
The Mean

ABSTRACT Introduction: The low pH of sports drinks may cause tooth enamel demineralization. Objective: To measure Vickers hardness of human enamel exposed to sports drinks. Methods: Human molars were used to collect the enamel samples. Each sample had a test surface (exposed to the drinks) and a control surface (unexposed). The samples were exposed to isotonic drinks Gatorade and Powerade, and to maltodextrin drinks Malto Advanced and Malto Active, for 10 minutes every 12 hours over 30 days. The Vickers microhardness test was conducted with three indentations on each surface. The mean of the indentations within each group was considered in the statistical analysis. Sports drinks variables were analyzed with ANOVA/Tukey (p≤0.01). The independent t-test was used in the comparison between the control and test surfaces of each drink (p ≤ 0.05). Results: Enamel exposure to Gatorade (p = 0.000) Malto Advanced (p = 0.000) and Malto Active (p = 0.000) was seen to significantly reduce microhardness, while the isotonic drink Powerade had no significant effect on enamel (p = 0.248). Conclusion: It was concluded that with the exception of the isotonic drink Powerade, all the sports drinks tested caused a reduction in the microhardness of human enamel. Evidence Level III; Therapeutic studies - Investigating the Results of Treatment.

scholarly journals Airpolishing effect on bovine enamel and the posterior remineralizing effect of saliva: estudo in vitro

2006 ◽  
Vol 14 (3) ◽  
pp. 193-197
Author(s):  
Helena Zaramella Vono Ribeiro ◽  
José Eduardo de Oliveira Lima ◽  
Bernardo Gonzalez Vono ◽  
Maria Aparcida de Andrade Moreira Machado ◽  
Salete Moura Bonifácio da Silva
Keyword(s):  
Sodium Bicarbonate ◽  
Artificial Saliva ◽  
Mean Value ◽  
Surface Microhardness ◽  
Mean Values ◽  
The Mean ◽  
Repairing Effect ◽  
The One ◽  
Bovine Enamel

PURPOSE: The aim of the present study was to evaluate the alterations of surface microhardness and wear caused by the sodium bicarbonate jet on bovine enamel and the further remineralizing effect of artificial saliva. METHODS: Fifteen enamel samples (4,0mm x 4,0mm) were used, which constituted the groups: no treatment (MI); treatment with sodium bicarbonate jet (MII and DI); treatment with sodium bicarbonate jet and immersion in saliva for one hour (MIII and DII), 24 hours (MIV and DIII) and 7 days (MV and DIV). Microhardness tests were carried out using a microdurometer in groups M and wear tests by a rugosimeter in groups D. The data were assessed by the one criterion variance analysis and Tukey test. RESULTS: The mean value of microhardness, in KHN, in groups MI, MII, MIII, MIV and MV were 359,80; 335,46; 369,20; 377,73 and 341,86, respectively, whereas the mean values in µm, of wear for group DI, DII, DIII and DIV were 0,564; 0,519; 0,441 and 0,428, respectively. CONCLUSIONS: The sodium bicarbonate jet caused a wear and a reduction in microhardness on the enamel surface; saliva promoted the recovery of initial condition surface microhardness and reduced the wear; the repairing effect of saliva on the surface microhardness alterations occurred within one hour of treatment, having no significant statistical difference from the effect obtained in 24 hours; the best saliva repairing effect on the wear occurred with treatment of 24 hours.

scholarly journals In Situ and In Vitro Effects of Two Bleaching Treatments on Human Enamel Hardness

2016 ◽  
Vol 27 (1) ◽  
pp. 56-59 ◽  
Author(s):  
Sandrina Henn-Donassollo ◽  
Cristiane Fabris ◽  
Morgana Gagiolla ◽  
Ícaro Kerber ◽  
Vinícius Caetano ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Oral Appliance ◽  
Water Cooling ◽  
Surface Microhardness ◽  
Tukey Test ◽  
Human Enamel ◽  
Before And After ◽  
In Vitro Effects

Abstract The aim of this study was to evaluate in vitro and in situ the effects of two bleaching treatments on human enamel surface microhardness. Sixty enamel slabs from recently extracted thirty molars were used. The specimens were polished with sandpapers under water-cooling. The enamel samples were randomly divided in four groups, treated with 10% hydrogen peroxide (HP) or Whitening Strips (WS) containing 10% hydrogen peroxide and using two conditions: in vitro or in situ model. For in situ condition, six volunteers wore an intra-oral appliance containing enamel slabs, while for in vitro condition the specimens were kept in deionized water after the bleaching protocols. The bleaching treatments were applied one-hour daily for 14 days. Similar amounts of bleaching agents were used in both conditions. Before and after bleaching treatments, microhardness was measured. Statistical analysis (ANOVA and Tukey test) showed that in the in situ condition there was no statistically significant microhardness reduction in the bleached enamel (p>0.05). Significant decrease in hardness was observed for enamel slabs bleached with both treatments in the in vitro condition (p<0.05). Regarding the bleaching agents, in situ results showed no difference between HP and WS, while in vitro WS produced the lowest hardness value. It could be concluded that there was no deleterious effect on enamel produced by any of the bleaching protocols used in the in situ model. The reduction of hardness was only observed in vitro.

scholarly journals STUDY OF THE EFFECT OF FLUORIDE ON LASER ENHANCED REMINERALIZATION OF DEMINERALIZED HUMAN ENAMEL

2021 ◽  
Vol 9 (01) ◽  
pp. 650-654
Author(s):  
Hanan Mansour Abdallah ◽  
◽  
Reham Magdy Ameen ◽  
Khaled El-Haddad ◽  
◽  
...  
Keyword(s):  
Diode Laser ◽  
Early Stage ◽  
Control Group ◽  
Surface Microhardness ◽  
Fluoride Toothpaste ◽  
Hardness Tester ◽  
Human Enamel ◽  
Demineralized Enamel ◽  
Topical Fluoride ◽  
Caries Lesions

Background: Enamel is regularly subjected to demineralization and remineralization under different oral circumstances. Any interruption in the balance between demineralization and remineralization can initiate the formation of incipient caries lesions. However, in the early stage of formation these lesions can be remineralizedusing various preventive measures. Topical fluorides have shown positive results in the prevention of caries in several studies. The aim of this study was to determine the effects of combination between diode laser and topical fluoride application on the surface microhardness of the demineralized enamel. Materials and Methods: Four caries-free human premolars were examined under the stereomicroscope to exclude teeth with surface enamel defects. Buccal enamel surface microhardness (SMH) for all samples was measured by Micro Vickers Hardness Tester (MVHT). The samples were demineralized by 15% Hydrochloric acid (HCl) with PH average 4.5, then the SMH was measured. The demineralized teeth were subjected to fluoride toothpaste after diode laser application. Third evaluation for enamel SMH was performed after remineralization. Results: Enamel SMH of the control group has shown the highest values followed by the remineralization group while the least values were measured in the demineralization group. Conclusions: The results obtained in the study lead to the conclusion that application of fluoride toothpaste after diode laser could enhance the remineralization potential of the demineralized enamel.

scholarly journals Evaluation of Eye Protection Filters Used with Broad-Spectrum and Conventional LED Curing Lights

2017 ◽  
Vol 28 (1) ◽  
pp. 9-15 ◽  
Author(s):  
Carlos José Soares ◽  
Monise de Paula Rodrigues ◽  
Andomar Bruno Fernandes Vilela ◽  
Erick René Cerda Rizo ◽  
Lorraine Braga Ferreira ◽  
...  
Keyword(s):  
Broad Spectrum ◽  
Emission Spectra ◽  
High Irradiance ◽  
Patient Simulator ◽  
Mean Values ◽  
Eye Protection ◽  
Tukey Test ◽  
Light Curing ◽  
The Mean

Abstract The high irradiance and the different emission spectra from contemporary light curing units (LCU) may cause ocular damage. This study evaluated the ability of 15 eye protection filters: 2 glasses, 1 paddle design, and 12 dedicated filters to block out harmful light from a monowave (HP-3M ESPE) and a broad-spectrum (Valo, Ultradent) LED LCU. Using the anterior sensor in the MARC-Patient Simulator (BlueLight Analytics) the irradiance that was delivered through different eye protection filters was measured three times. The LCUs delivered a similar irradiance to the top of the filter. The mean values of the light that passed through the filters as percent of the original irradiance were analyzed using two-way ANOVA followed by Tukey test (a= 0.05). The emission spectra from the LCUs and through the filters were also obtained. Two-way ANOVA showed that the interaction between protective filters and LCUs significantly influenced the amount of light transmitted (p< 0.001). Tukey test showed that the amount of light transmitted through the protective filters when using the HP-3M-ESPE was significantly greater compared to when using the Valo, irrespective of the protective filter tested. When using the HP-3M-ESPE, the Glasses filter allowed significantly more light through, followed by XL 3000, ORTUS, Google Professional, Gnatus filters. The Valo filter was the most effective at blocking out the harmful light. Some protective filters were less effective at blocking the lower wavelengths of light (<420 nm). However, even in the worst scenario, the filters were able to block at least 97% of the irradiance.

Articulatory Behavior Pre and Post Full-Mouth Tooth Extraction and Alveoloplasty

1980 ◽  
Vol 23 (3) ◽  
pp. 630-645 ◽  
Author(s):  
Gerald Zimmermann ◽  
J.A. Scott Kelso ◽  
Larry Lander
Keyword(s):  
Control Subject ◽  
High Speed ◽  
Tooth Extraction ◽  
Kinematic Parameters ◽  
Experimental Conditions ◽  
Mean Values ◽  
Articulatory Movements ◽  
The Mean ◽  
Experimental Subjects ◽  
Normal Speech

High speed cinefluorography was used to track articulatory movements preceding and following full-mouth tooth extraction and alveoloplasty in two subjects. Films also were made of a control subject on two separate days. The purpose of the study was to determine the effects of dramatically altering the structural dimensions of the oral cavity on the kinematic parameters of speech. The results showed that the experimental subjects performed differently pre and postoperatively though the changes were in different directions for the two subjects. Differences in both means and variabilities of kinematic parameters were larger between days for the experimental (operated) subjects than for the control subject. The results for the Control subject also showed significant differences in the mean values of kinematic variables between days though these day-to-day differences could not account for the effects found pre- and postoperatively. The results of the kinematic analysis, particularly the finding that transition time was most stable over the experimental conditions for the operated subjects, are used to speculate about the coordination of normal speech.

Comparative Study of Intranasal, Subcutaneous and Intravenous Administration of Desamino-D-Arginine Vasopressin (DDAVP)

1986 ◽  
Vol 55 (01) ◽  
pp. 108-111 ◽  
Author(s):  
M Köhler ◽  
P Hellstern ◽  
C Miyashita ◽  
G von Blohn ◽  
E Wenzel
Keyword(s):  
Factor Viii ◽  
Von Willebrand Factor ◽  
Factor Xii ◽  
Additional Advantage ◽  
Mean Values ◽  
Routes Of Administration ◽  
The Mean ◽  
Von Willebrand ◽  
Willebrand Factor ◽  
Factor Antigen

SummaryThis study was performed to evaluate the influence of different routes of administration on the efficacy of DDAVP treatment. Ten healthy volunteers received DDAVP intranasally (i.n.), subcutaneously (s.c.) and intravenously (i.v.) in a randomized cross-over trial. Factor XII and high molecular weight (HMW)-kininogen levels increased only slightly after DDAVP administration. The mean increase of factor VIII: C was 3.1 (i. v.), 2.3 (s. c.), and 1.3 (i.n.) - fold over baseline. Ristocetin cofactor (von Willebrand factor antigen) increased 3.1 (2.5), 2.0 (2.3) and 1.2 (1.2) - fold over baseline mean values after i.v., s.c. and i.n. DDAVP, respectively. The half-disappearance time of factor VIII and von Willebrand factor (vWF) after DDAVP ranged from five (factor VIII: C) to eight hours (vWF). The mean increase of fibrinolytic activity was more pronounced after i.v. DDAVP. The antidiuretic effect was moderate with no apparent differences between the routes of application. This study provides further evidence that both i.v. and s.c. DDAVP administration result in an appropriate and reliable stimulation of haemostasis. An additional advantage of s. c. administration is its suitability for home treatment.

Comparative Study of effectiveness of mobilization with movement (MWM) and End range mobilization (ERM) techniques in frozen shoulder

2018 ◽  
Vol 4 (4) ◽  
pp. 519-522
Author(s):  
Jeyakumar S ◽  
Jagatheesan Alagesan ◽  
T.S. Muthukumar
Keyword(s):  
Range Of Motion ◽  
Frozen Shoulder ◽  
Type I ◽  
Mean Values ◽  
Functional Activities ◽  
Group A ◽  
The Mean ◽  
Group B

Background: Frozen shoulder is disorder of the connective tissue that limits the normal Range of motion of the shoulder in diabetes, frozen shoulder is thought to be caused by changes to the collagen in the shoulder joint as a result of long term Hypoglycemia. Mobilization is a therapeutic movement of the joint. The goal is to restore normal joint motion and rhythm. The use of mobilization with movement for peripheral joints was developed by mulligan. This technique combines a sustained application of manual technique “gliding” force to the joint with concurrent physiologic motion of joint, either actively or passively. This study aims to find out the effects of mobilization with movement and end range mobilization in frozen shoulder in Type I diabetics. Materials and Methods: 30 subjects both male and female, suffering with shoulder pain and clinically diagnosed with frozen shoulder was recruited for the study and divided into two groups with 15 patients each based on convenient sampling method. Group A patients received mobilization with movement and Group B patients received end range mobilization for three weeks. The outcome measurements were SPADI, Functional hand to back scale, abduction range of motion using goniometer and VAS. Results: The mean values of all parameters showed significant differences in group A as compared to group B in terms of decreased pain, increased abduction range and other outcome measures. Conclusion: Based on the results it has been concluded that treating the type 1 diabetic patient with frozen shoulder, mobilization with movement exercise shows better results than end range mobilization in reducing pain and increase functional activities and mobility in frozen shoulder.

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