scholarly journals Study Regarding the Surface State of Composite Resins After Finishing and Polishing Using Different Systems

2017 ◽  
Vol 54 (4) ◽  
pp. 689-693
Author(s):  
Sorin Andrian ◽  
Gianina Iovan ◽  
Galina Pancu ◽  
Claudiu Topoliceanu ◽  
Andrei Georgescu ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Surface State ◽  
State Assessment ◽  
Composite Resins ◽  
Abrasive Particles ◽  
Group 4 ◽  
One Step ◽  
Group 3 ◽  
Group 2 ◽  
Cylindrical Samples

The aim of this study was to evaluate the influence of different finishing and polishing systems and of composite resins structure on surface state of the restoration. Cylindrical samples from two different composite resins (Filtek Z 550 and Filtek Z 250, 3M ESPE) were obtained. In group 1 the samples were not finished and polished. In groups 2-4 the samples were submitted to finishing procedure using two tungsten carbide burs, then polished using three different polishing systems: three steps diamond abrasive polishers (Kenda CGI, Lichtenstein) - group 2, one step silicon carbide abrasive particles brush (Occlubrush, KerrHawe SA, Switzerland) - group 3 and two steps Sof-Lex spiral wheels (3M ESPE) - group 4. Half of the samples in each group were subjected to surface microstructure evaluation using a scanning electron mycroscope. The other half of the samples was subjected to surface state assessment using profilometery. All the investigated finishing and polishing systems leaded to increased surface roughness when compared to the roughness of composite resins placed in direct contact to celluloid clear matrix. The surface roughness of both microfilled-hybrid and nanofilled-hybrid composite resins finished and polished with different systems were influenced mostly by the polishing system and less by the composite resin structure.

scholarly journals Corrosion resistance of surface modified nickel titanium archwires

2013 ◽  
Vol 84 (2) ◽  
pp. 358-367 ◽  
Author(s):  
Manu Krishnan ◽  
Saraswathy Seema ◽  
A. Vinod Kumar ◽  
N. Parvatha Varthini ◽  
Kalathil Sukumaran ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Corrosion Resistance ◽  
Surface Characteristics ◽  
Group 4 ◽  
Group 3 ◽  
Group 5 ◽  
Group 2 ◽  
Surface Modified ◽  
Niti Wires ◽  
Group 1

ABSTRACT Objective: To compare the corrosion behavior of commercially available surface modified nickel titanium (NiTi) arch wires with respect to a conventional NiTi and to evaluate its association with surface characteristics. Materials and Methods: Five types of surface modified arch wires and a conventional NiTi arch wire, all from different manufacturers, were evaluated for their corrosion resistance from breakdown potential in an anodic polarization scan in Ringer's solution. Surface characteristics were determined from scanning electron microscopy, atomic force microscopy, and energy dispersive analysis. One-way analysis of variance and post hoc Duncan's multiple range tests were used to evaluate statistical significance. Results: Surface modified NiTi wires showed significant improvement in corrosion resistance and reduction in surface roughness values. Breakdown potentials increased in the order of group 6 (conventional; 204 mV) < group 1 (nitride; 333 mV) < group 5 (epoxy resin; 346mV) < group 3 (oxide; 523 mV) < group 2 (gold; 872 mV) < group 4 (Teflon; 1181 mV), but root mean square (RMS) roughness values, which indicated surface roughness, followed a different pattern: group 3 (oxide; 74.12 nm) < group 1 (nitride; 221.651 nm) < group 4 (Teflon; 278.523 nm) < group 2 (gold; 317.894 nm) < group 5 (epoxy resin; 344.236 nm) < group 6 (conventional; 578.555 nm). Conclusions: Surface modification of NiTi wires proved to be effective in improving its corrosion resistance and decreasing surface roughness. However, neither factor could maintain a direct, one-to-one relationship. It meant that the type and nature of coating material can effectively influence the anticorrosive features of NiTi wires, compared with its surface roughness values.

scholarly journals A Comparative Evaluation of Three Commercially Available Dentin Desensitizers on the Shear Bond Strength of Composite Resins: An in vitro Study

2015 ◽  
Vol 5 (2) ◽  
pp. 65-68
Author(s):  
Shruti Patil ◽  
Prajna Shetty
Keyword(s):  
Bond Strength ◽  
Comparative Evaluation ◽  
Shear Bond Strength ◽  
In Vitro Study ◽  
Composite Resins ◽  
Group 4 ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

ABSTRACT Background The dentin desensitizers available for in-office application for prevention and/or treatment of post restorative dentinal hypersensitivity, act by blocking the open dentinal tubules. In doing so, they may influence the bond strength of the restorative resins. Thus, the aim of the study was to evaluate the effect of desensitizers on the shear bond strength of dentin adhesives and to check the extent of dentinal tubule occlusion caused by these desensitizers. Materials and Methods Sixty-four premolars were randomly divided into four groups of sixteen each. The middle depth dentin was exposed by on the buccal surface and was etched using 37% phosphoric acid and rinsed. They were assigned to, Group 1: Gluma desensitizer, Group 2: Vivasens desensitizer, Group 3: Gluma Comfort Bond and desensitizer, and Group 4: Adper Single Bond 2. Composite resin post of 2 mm in height and width were built on these specimens. The samples were then mounted in acrylic resin blocks. Universal testing machine was used to test the shear bond strength. The data were analyzed using one-way analysis of variance (ANOVA) and post hoc Tukey's test. Results The mean values of the shear bond strength were for: Group 1—18.61 ± 1.03 MPa, Group 2—17.53 ± 1.36 MPa, Group 3—22.63 ± 1.61 MPa and Group 4—23.12 ± 1.02 MPa. There was a statistically significant difference (p < 0.05) among the groups. Conclusion The use of dentin desensitizers’ influences bond strength between the tooth and the adhesive. Among the various agents, the single bottle system containing Gluma comfort bond and desensitizer had the best adhesion among the desensitizer groups. How to cite this article Patil S, Naik B, Shetty P. A Comparative Evaluation of Three Commercially Available Dentin Desensitizers on the Shear Bond Strength of Composite Resins: An in vitro Study. J Contemp Dent 2015;5(2):65-68.

scholarly journals EFFECT OF THREE POLISHING SYSTEMS ON THE ROUGHNESS AND GLOSSINESS OF NANOCERAMIC COMPOSITE RESIN

2020 ◽  
pp. 16-18
Author(s):  
LIDYA LOLITA ◽  
ENDANG SUPRASTIWI ◽  
DEWA AYU NYOMAN PUTRI ARTINIGSIH ◽  
ANDRIA KUSWADI
Keyword(s):  
Composite Resin ◽  
Control Group ◽  
Step Method ◽  
Group 4 ◽  
One Step ◽  
Group 3 ◽  
Group 2 ◽  
Method Group ◽  
Group 1

Objective: The purpose of resin polish is to produce a restored surface that is similar to that of enamel. The objective of this study was to analyze thepolishing effect of three systems in terms of the comparative roughness or glossiness achieved with nanoceramic composite resin.Methods: Forty samples of nanoceramic composite resin were divided into four groups as follows: Group 1 was the control group, whichinvolved polymerization using Mylar strips; Group 2 involved a one-step polishing method; Group 3 involved a two-step method; and Group4 involved a four-step method. After performing these methods, the comparative roughness and glossiness of the resulting surfaces weremeasured.Results: Group 4 generated the lowest roughness value, with an almost equal value to that of the control group, which was followed by Group 3 andGroup 2. The best surface in terms of glossiness was achieved in Group 4.Conclusion: The polishing system involving the four-step method generated the lowest roughness value and the highest surface glossiness value.

scholarly journals Effect of different post-cure polymerization treatment on composite resin hardness

2015 ◽  
Vol 63 (4) ◽  
pp. 426-431
Author(s):  
Ariani Rodrigues DIMER ◽  
Guilherme Anziliero AROSSI ◽  
Leonardo Haerter dos SANTOS ◽  
Diego Rafael KAPPAUN
Keyword(s):  
Composite Resin ◽  
Hardness Test ◽  
Composite Resins ◽  
Control Group ◽  
Group 4 ◽  
Significant Difference ◽  
Group 3 ◽  
Group 2 ◽  
Vickers Hardness Test ◽  
Group 1

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.

scholarly journals EFEITO DOS PROCEDIMENTOS DE ACABAMENTO E POLIMENTO NA RUGOSIDADE SUPERFICIAL DA CERÂMICA NORITAKE®

2016 ◽  
Vol 7 (2) ◽  
Author(s):  
Mario Cezar Oliveira ◽  
Alex Correia Vieira ◽  
Adriana Castro Andrade ◽  
Indira Almeida Oliveira
Keyword(s):  
Surface Roughness ◽  
The Other ◽  
Control Group ◽  
Group 4 ◽  
Group 3 ◽  
Group 2 ◽  
Diamond Paste ◽  
Group 1

The aim of this study was to evaluate the surface roughness of Noritake® ceramic after different methods of finishing and polishing. 40 specimens of Noritake® ceramic were randomly divided into 4 groups (n=10) and subjected to different methods of finishing and polishing: Group 1 (control) - glaze; Group 2 - abrasive rubbers Astropol (Ivoclar Vivadent), felt disc and diamond paste; Group 3 - abrasive rubbers (Edenta), felt disc and diamond paste; Group 4 - Sof-Lex discs (3M ESPE), felt disc and diamond paste. Subsequently, the surface roughness was measured with rugosimeter (Mitutoyo SJ 301). The control group (G1) had the lowest surface roughness (0.68 μm) that was different statistically to the other groups (p0.05). The different methods of finishing and polishing were not able to promote a surface as smooth as the application of glaze in the ceramics tested.

Effect of pH Cycling Followed by Simulated Toothbrushing on the Surface Roughness and Bacterial Adhesion of Bulk-fill Composite Resins

2020 ◽  
Vol 45 (2) ◽  
pp. 209-218 ◽  
Author(s):  
DC Somacal ◽  
FB Manfroi ◽  
MSG Monteiro ◽  
SD Oliveira ◽  
HR Bittencourt ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Bacterial Adhesion ◽  
Composite Resin ◽  
Composite Resins ◽  
Sem Images ◽  
Effect Of Ph ◽  
Group 4 ◽  
Ph Cycling ◽  
Group 2

SUMMARY The aim was to evaluate, in vitro, quantitatively and qualitatively, the effect of pH cycling and simulated toothbrushing on surface roughness (Ra) and bacterial adhesion (Cn) of bulk-fill composite resins. Thirty specimens of each composite resin, 5 mm wide and 4 mm high, were obtained: group 1 (control): Filtek Z250 (Z250); group 2: Filtek Bulk-Fill (FTK); group 3: Tetric N-Ceram Bulk-Fill (TTC); and group 4: Aura Bulk-Fill (AUR). After 24 hours, the specimens were polished and then alternated with demineralization/remineralization solutions for 15 cycles of 24 hours each at 37°C. Then the specimens were submitted to simulated toothbrushing. The Ra and Cn measurements were quantitatively analyzed in three stages: after polishing (Ra0 and Cn0), after pH cycling (Ra1 and Cn1), and after simulated toothbrushing (Ra2 and Cn2). The Ra values were submitted to two-way analysis of variance, followed by the Tukey test (α=0.05). The Kruskal-Wallis test, followed by multiple comparisons, was applied for Cn analysis. Surface topography and bacterial adhesion were observed by scanning electron microscopy (SEM). Z250, FTK, and TTC showed no significant change in Ra regardless of the treatment performed; AUR obtained increased Ra at Ra2 (p&lt;0.05). FTK differed from the others at Cn0 and Cn1 (p&lt;0.05). At Cn2, there was no difference among the composite resins. SEM images showed the exposure of fillers and microcavities at Ra1 and Ra2. There was greater bacterial adhesion at Cn1 for Z250 and FTK. It was concluded that the pH cycling caused surface degradation of all composite resins, which was potentiated by simulated toothbrushing. However, only AUR presented an increased Ra. Bacterial adhesion occurred on all composite resins after pH cycling; however, after simulated toothbrushing, adhesion of dispersed bacteria was similar for all the composite resin groups.

scholarly journals Influence of different photoinitiators on the resistance of union in bovine enamel: an in vitro study

2020 ◽  
Vol 9 (10) ◽  
pp. e5639108832
Author(s):  
Paulo Ricardo Barros de Campos ◽  
Lizandra Esper Serrano ◽  
João Victor Frazão Câmara ◽  
Renata Aguiar Costa Di Leta Gregorio ◽  
Raquel Rytholz ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Composite Resins ◽  
Adhesive Systems ◽  
Group 4 ◽  
Microtensile Test ◽  
Group 3 ◽  
Group 2 ◽  
Bovine Enamel ◽  
Group 1

To evaluate the action of photoinitiators on the microtensile resistance of adhesive systems and resins composed in bovine enamel. Forty dental fragments, with flat and smooth enamel surfaces, obtained from the coronary buccal face of healthy bovine incisors, were randomly assigned to 4 experimental groups (n = 10) according to the different adhesive systems and composite resins used: Group 1- Ambar APS + Vittra APS; Group 2- Ambar APS + Opallis; Group 3- Ambar + Vittra APS; Group 4- Ambar + Opallis. After composite restoration, the samples were sectioned to obtain toothpicks that were subjected to the microtensile test (1.0 mm/min). The data obtained were subjected to statistical analysis. The Kruskal-Wallis test revealed no significant differences between groups (p <0.05). Values ​​in MPa were: G1- 18.58 MPaa; G2 - 19.83 MPaa; G3- 19.87 MPaa; G4- 20.99 MPaa. The result of the Mann-Whitney test showed no significant differences due to the adhesive (Ambar Universal- 19.58 MPaa, Ambar APS Universal- 19.87 MPaa) and the composite resin used (Vittra APS- 19.52 MPAa, Opallis - 20.56 MPAa). The use of different photoinitiators in the composition of adhesive systems and restorative composites did not influence their adhesive resistance values ​​due to the standardization of the factors that influence their cure pattern.

Role of TiF4 in Microleakage of Silorane and Methacrylatebased Composite Resins in Class V Cavities

2016 ◽  
Vol 17 (3) ◽  
pp. 240-247
Author(s):  
Zahra Jowkar ◽  
Fatemeh Koohpeima ◽  
Farahnaz Sharafeddin ◽  
Samaneh Ahmadzadeh ◽  
Mohammad Javad Mokhtari ◽  
...  
Keyword(s):  
Resin Composite ◽  
Composite Resins ◽  
Class V ◽  
Group 4 ◽  
The Social ◽  
Significant Difference ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

ABSTRACT Aim This study investigated the effect of TiF4 solution pretreatment on microleakage of silorane and nanofilled methacrylatebased composites in class V cavities. Materials and methods Forty-eight intact premolar teeth were randomly allocated to four groups of 12 teeth. Restorative techniques after standard class V tooth preparations were as follows: Group 1, Filtek P90 composite; group 2, Filtek Z350 XT; group 3, TiF4 solution pretreatment and Filtek P90 composite; group 4, TiF4 solution pretreatment and Filtek Z350 XT. After storing the specimens in distilled water at 37°C for 24 hours and followed by immersion of the specimens in a 0.5% basic-fuchsin solution for 24 hours, they were sectioned buccolingually to obtain four surfaces for each specimen for analysis of microleakage using a stereomicroscope. Data analysis was performed using Kruskal-Wallis test to compare the four groups and the Mann- Whitney test for paired comparisons with Statistical Package for the Social Sciences (SPSS) version 17 software. Results At the enamel margins, microleakage score of the Filtek Z350 XT group was lower than those of the Filtek P90 with and without the application of the TiF4 (p = 0.009 and p = 0.031 respectively). At the dentin margins, groups 3 and 4 (TiF4+Filtek P90 and TiF4+Filtek z350 XT respectively) showed significantly lower microleakage than group 1 (Filtek P90). However, there was no significant difference between other groups (p > 0.05). Conclusion At the enamel margins, microleakage score of the silorane-based composite was more than that of the nanofilled composite. No significant differences were observed between the other groups. At the dentin margins, for the silorane-based composite restorations, TiF4 solution pretreatment resulted in significantly lower microleakage. However, the similar result was not observed for Filtek Z350 XT. Also, no significant difference was observed between microleakage scores of Filtek P90 and Filtek Z350 XT with or without TiF4 pretreatment. Clinical significance In spite of better mechanical and physical properties of modern composites than earlier methacrylate-based composites, polymerization shrinkage has been remaining as one of the main shortcomings of them. Different methods, such as using new low shrinkage resin composites and different dentin pretreatments, have been suggested to overcome this problem. This study evaluated the effect of TiF4 as pretreatment on microleakage of class V tooth preparations restored with a nanocomposite and a silorane-based resin composite. How to cite this article Koohpeima F, Sharafeddin F, Jowkar Z, Ahmadzadeh S, Mokhtari MJ, Azarian B. Role of TiF4 in Microleakage of Silorane and Methacrylate-based Composite Resins in Class V Cavities. J Contemp Dent Pract 2016;17(3):240-247.

Morphological Changes in the Rat Granulosa Cell Surface During Differentiation Induced by Estradiol and Gonadotropins

1977 ◽  
Vol 35 ◽  
pp. 484-485
Author(s):  
P. Bagavandoss ◽  
JoAnne S. Richards ◽  
A. Rees Midgley
Keyword(s):  
Cell Surface ◽  
Granulosa Cell ◽  
Morphological Changes ◽  
Follicular Development ◽  
Female Rats ◽  
Functional Changes ◽  
Group 4 ◽  
Group 3 ◽  
Group 5 ◽  
Group 2

During follicular development in the mammalian ovary, several functional changes occur in the granulosa cells in response to steroid hormones and gonadotropins (1,2). In particular, marked changes in the content of membrane-associated receptors for the gonadotropins have been observed (1).We report here scanning electron microscope observations of morphological changes that occur on the granulosa cell surface in response to the administration of estradiol, human follicle stimulating hormone (hFSH), and human chorionic gonadotropin (hCG).Immature female rats that were hypophysectcmized on day 24 of age were treated in the following manner. Group 1: control groups were injected once a day with 0.1 ml phosphate buffered saline (PBS) for 3 days; group 2: estradiol (1.5 mg/0.2 ml propylene glycol) once a day for 3 days; group 3: estradiol for 3 days followed by 2 days of hFSH (1 μg/0.1 ml) twice daily, group 4: same as in group 3; group 5: same as in group 3 with a final injection of hCG (5 IU/0.1 ml) on the fifth day.

Correlation of γ-radioactivity and Scanning Electron Microscopy in measurement of retention of 111Indium-labeled canine endothelial cells on synthetic vascular grafts

1989 ◽  
Vol 47 ◽  
pp. 886-887
Author(s):  
E.J. Prendiville ◽  
S. Laliberté Verdon ◽  
K. E. Gould ◽  
K. Ramberg ◽  
R. J. Connolly ◽  
...  
Keyword(s):  
Blood Flow ◽  
Ex Vivo ◽  
Vascular Grafts ◽  
Retention Data ◽  
Vascular Prostheses ◽  
Group 4 ◽  
Human Fibronectin ◽  
Insufficient Time ◽  
Group 3 ◽  
Group 2

Endothelial cell (EC) seeding is postulated as a mechanism of improving patency in small caliber vascular grafts. However the majority of seeded EC are lost within 24 hours of restoration of blood flow in previous canine studies . We postulate that the cells have insufficient time to fully develop their attachment to the graft surface prior to exposure to hemodynamic stress. We allowed EC to incubate on fibronectin-coated ePTFE grafts for four different time periods after seeding and measured EC retention after perfusion in a canine ex vivo shunt circuit.Autologous canine EC, were enzymatically harvested, grown to confluence, and labeled with 30 μCi 111 Indium-oxine/80 cm 2 flask. Four groups of 5 cm x 4 mm ID ePTFE vascular prostheses were coated with 1.5 μg/cm.2 human fibronectin, and seeded with 1.5 x 105 EC/ cm.2. After seeding grafts in Group 1 were incubated in complete growth medium for 90 minutes, Group 2 were incubated for 24 hours, Group 3 for 72 hours and Group 4 for 6 days. Grafts were then placed in the canine ex vivo circuit, constructed between femoral artery and vein, and subjected to blood flow of 75 ml per minute for 6 hours. Continuous counting of γ-activity was made possible by placing the seeded graft inside the γ-counter detection crystal for the duration of perfusion. EC retention data after 30 minutes, 2 hours and 6 hours of flow are shown in the table.

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