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1.
Biomed Res Int ; 2021: 9987860, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34195290

RESUMO

Purpose: The potential of UV-mediated photofunctionalization to enhance the resin-based luting agent bonding performance to aged materials was investigated. Methods: Sixty samples of each material were prepared. Yttria-stabilized zirconia (YZr) and Pd-Au alloy (Pd-Au) plates were fabricated and sandblasted. Lithium disilicate glass-ceramic (LDS) was CAD-CAM prepared and ground with #800 SiC paper. Half of the specimens were immersed in machine oil for 24 h to simulate the carbon adsorption. Then, all of the specimens (noncarbon- and carbon-adsorbed) were submitted to UV-mediated photofunctionalization with a 15 W UV-LED (265 nm, 300 mA, 7692 µW/cm2) for 0 (control groups), 5, and 15 min and subjected to contact angle (Ɵ) measurement and bonded using a resin cement (Panavia™ V5, Kuraray Noritake, Japan). The tensile bond strength (TBS) test was performed after 24 h. The Ɵ (°) and TBS (MPa) data were statistically analyzed using two-way ANOVA and Bonferroni correction tests (α = 0.05). Results: In the carbon-adsorbed groups, UV-mediated photofunctionalization for 5 min significantly decreased Ɵ of all materials and increased TBS of YZr, and UV for 15 min significantly increased the TBS of LDS and Pd-Au. In noncarbon-adsorbed groups, UV-photofunctionalization did not significantly change the Ɵ or TBS except YZr specimens UV-photofunctionalized for 15 min. Conclusion: UV-mediated photofunctionalization might have removed the adsorbed hydrocarbon molecules from the materials' surfaces and enhanced bond strengths of Panavia™ V5 to YZr, LDS, and Pd-Au. Additionally, UV-mediated photofunctionalization improved the overall TBS of YZr. Further investigation on the optimum conditions of UV photofunctionalization on indirect restorative materials should be conducted.


Assuntos
Ligas Dentárias , Fotoquímica/métodos , Cimentos de Resina/química , Adsorção , Carbono , Cerâmica , Desenho Assistido por Computador , Colagem Dentária , Porcelana Dentária , Análise do Estresse Dentário , Ouro/química , Humanos , Hidrocarbonetos/química , Teste de Materiais , Paládio/química , Estudos Prospectivos , Propriedades de Superfície , Resistência à Tração , Raios Ultravioleta , Ítrio/química , Zircônio/química
2.
Dent Mater J ; 40(2): 385-392, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33208575

RESUMO

This study aimed to evaluate the effect of silane coupling agent contamination on the microtensile bond strength (µTBS) of 3-step etch-and-rinse adhesives on dentin. Flat occlusal dentin surfaces were prepared and randomly divided into 8 groups (n=20) based on the tested adhesives; Scotchbond Multi-purpose or Optibond FL, with contamination of an experimental silane (2 vol% of 3-m ethacryloxypropyltrimethoxysilane at pH 4.5) before acid-etching, after-etching or after-priming; while the groups without silane contamination served as controls. µTBS data were analyzed by two-way ANOVA and Tukey's HSD tests at a significance level of 0.05. Additional specimens of contaminated dentin were used to analyze changes in the organic molecules by Fourier transform infrared spectroscopy (FTIR). Silane contamination before acid-etching did not significantly change µTBS (p>0.05), but contamination after-etching and after-priming significantly decreased µTBS of both adhesives (p<0.05). Silane contamination had an adverse effect on the dentin bond strength of 3-step etch-and-rinse adhesives especially after-priming.


Assuntos
Colagem Dentária , Adesivos Dentinários , Adesivos , Resinas Compostas , Cimentos Dentários , Dentina , Teste de Materiais , Cimentos de Resina , Silanos , Resistência à Tração
3.
Dent Mater J ; 39(5): 892-899, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32448851

RESUMO

The effect of different air-blowing strategies using a prototype of a newly developed clinically applicable warm air-blowing device on the microtensile bond strength (µTBS) of one-step self-etch adhesives (1-SEAs) to human root-canal dentin was evaluated. Post cavities (8 mm depth, 1.5 mm diameter) were prepared and bonded with four 1-SEAs. Air-blowing was performed using normal air (23±1°C) for 10 or 20 s; warm air (60±1°C) for 10 or 20 s; or their combination for 10 s (5 s normal, 5 s warm) or 20 s (10 s normal, 10 s warm). After filling with corresponding core materials and 24-h water storage, µTBS test was performed. For three of the 1-SEAs, combined air-blowing for 20 s significantly increased µTBS compared to other air-blowing strategies (p<0.05). This suggests that the combination of normal and warm air-blowing for 20 s can enhance solvent evaporation from 1-SEAs, thus resulting in their improved bonding performance to root-canal dentin.


Assuntos
Colagem Dentária , Adesivos , Cimentos Dentários , Cavidade Pulpar , Dentina , Adesivos Dentinários , Humanos , Teste de Materiais , Cimentos de Resina , Resistência à Tração
4.
Dent Mater J ; 38(2): 233-240, 2019 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-30449829

RESUMO

The repair microshear bond strengths (µSBSs) to resin matrices in 4 different cured-composites after water storage (0, 60 s, 1 week, 1 month) were evaluated. Three different adhesive application methods to the cured-composites were performed; (1) none, (2) onestep self-etch adhesive application, and (3) one-step self-etch adhesive application with a silane coupling agent. Degree of conversion (DC) of the composite discs was determined using ATR/FT-IR with a time-based spectrum analysis. Initially, the amount of un-reacted resin monomers in the repaired cured-composite contributed to the bonding performance of newly-filled uncured-composite to resin matrix of the cured-composite. Adhesive application could not improve their repair µSBS. After 1-month of water-storage, the repair µSBS was dependent on material, which either reduced or did not and was not influenced by their amount of un-reacted resin monomers. When repairing aged composite resin, the appropriate adhesive application procedures were different among resin composites.


Assuntos
Colagem Dentária , Cimentos de Resina , Resinas Compostas , Teste de Materiais , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Resistência à Tração , Água
5.
J Adhes Dent ; 20(6): 541-547, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30564801

RESUMO

PURPOSE: To evaluate the effect of a polymerization accelerator on the microtensile bond strength (µTBS) of etch-and-rinse and self-etch adhesives to eugenol-contaminated dentin. MATERIALS AND METHODS: Sixty flat dentin surfaces were prepared from human molars. Half of the specimens were restored with zinc oxide eugenol temporary cement (IRM) (eugenol-contaminated group) and the other half remained without restoration (control group). After 24-h storage, the cement was mechanically removed. Then the specimens in each group were further divided into three subgroups based on the application procedure of a polymerization accelerator (p-toluenesulfinic acid sodium salt; Accel): no application, 10-s application, or 30-s application. After air drying, the dentin surfaces were bonded with either a three-step etch-and-rinse adhesive (OptiBond FL) or a two-step self-etch adhesive (Clearfil SE Bond) and restored with composite. After 24-h water storage, the bonded specimens were subjected to the µTBS test. Data were analyzed by three-way ANOVA and Dunnett's T3 test (p < 0.05). RESULTS: The eugenol-contaminated groups had significantly lower µTBS than the control groups with both types of adhesives (p < 0.05), and the application of Accel significantly increased the compromised µTBS to eugenol-contaminated dentin. Optibond FL presented significantly higher µTBS to eugenol-contaminated dentin than did Clearfil SE Bond (p < 0.05). CONCLUSION: The application of a polymerization accelerator on eugenol-contaminated dentin prior to adhesive resin application increased the µTBS of both the three-step etch-and-rinse and two-step self-etch adhesive.


Assuntos
Luzes de Cura Dentária , Colagem Dentária , Cimentos Dentários , Eugenol , Resistência à Tração , Condicionamento Ácido do Dente , Cimentos Dentários/química , Cimentos Dentários/efeitos da radiação , Dentina/efeitos da radiação , Eugenol/análise , Humanos , Polimerização/efeitos da radiação , Tolueno/análogos & derivados
6.
J Adhes Dent ; 20(5): 425-433, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30375582

RESUMO

PURPOSE: To evaluate the effect of water aging of adherend composite on repair bond strength to nanofilled composites with specific fillers using different bonding agents. MATERIALS AND METHODS: Three nanofilled composites - Beautifil II with S-PRG filler (BE) / Filtek Supreme ultra with nanocluster filler (SP) / Estelite Σ Quick (ES) - and one microhybrid composite, Clearfil APX (AP), were used in this study. The composite disks were immersed in water for different durations (immediate, 1 week, 2 weeks or 1 month), and then the polished surfaces were treated with one of three bonding agents - no treatment (control), application of Clearfil SE One (SE), application of Clearfil SE One plus Clearfil Porcelain Bond Activator (PB) - then filled with a repair composite. The bonded composite disks were subjected to the microshear bond strength (µSBS) test. Additionally, water sorption (Wsp) and solubility (Wsl) of the resin composite were measured. The µSBS data were was statistically analyzed using a three-way ANOVA and t-test with Bonferroni correction for multiple comparisons. RESULTS: Water aging of adherend composite affected the repair bond strength (p < 0.05). For BE, SP, and ES, application of an adhesive agent improved repair bond strengths to water-aged composites (p < 0.05), but adding a silane coupling agent could not (p > 0.05). For AP, the µSBS significantly increased, with control group < SE group < PB group (p < 0.05). CONCLUSION: Microhybrid composite was a more suitable material for composite repair than nanofilled composite, due to adhesion to exposed, larger silica fillers. S-PRG filler and nanocluster filler in the nanofilled composites played a slight role in improving their repair bonding performances with the bonding agents tested.


Assuntos
Resinas Compostas/química , Colagem Dentária/métodos , Materiais Dentários/química , Água/química , Bis-Fenol A-Glicidil Metacrilato , Polimento Dentário , Cura Luminosa de Adesivos Dentários , Teste de Materiais , Cimentos de Resina/química , Resistência ao Cisalhamento , Propriedades de Superfície , Fatores de Tempo
7.
Dent Mater J ; 37(3): 506-514, 2018 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-29491200

RESUMO

We evaluated the effect of different curing strategies for universal adhesives on micro-tensile bond strength (µTBS) between resin cement and dentin and/or between resin cement and indirect resin composite. Flat coronal dentin surfaces and composite resin disks were pretreated with silane-containing universal adhesives, with or without light-curing on the dentin-side and/or composite resin disk-side. Resin disks were luted onto the pretreated dentin surfaces with the corresponding dual-cure adhesive resin cements and light-cured, and cut into beams after 24-h water storage. After 0 or 10,000 thermocycles (5ºC/55ºC) in a water bath, the µTBS of the composite resin disk-dentin beam was tested. The µTBS was highest when universal adhesives were applied to both the dentin- and the indirect composite resin disk-side, followed by light-curing. Thermocycling decreased µTBS in all but the Scotchbond Universaltreated group, with light-curing on both sides. The effect of curing strategies is dependent upon the materials.


Assuntos
Resinas Acrílicas/química , Resinas Compostas/química , Colagem Dentária/métodos , Adesivos Dentinários/química , Poliuretanos/química , Restauração Dentária Permanente , Análise do Estresse Dentário , Humanos , Técnicas In Vitro , Cura Luminosa de Adesivos Dentários , Teste de Materiais , Cimentos de Resina , Resistência à Tração
8.
Dent Mater ; 34(3): 434-441, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29233540

RESUMO

OBJECTIVES: Smear layer deproteinizing was proved to reduce the organic phase of smear layer covered on dentin surface. It was shown to eliminate hybridized smear layer and nanoleakage expression in resin-dentin bonding interface of two-step self-etch adhesive. This study aimed to investigate those effects on various one-step self-etch adhesives. METHODS: Four different one-step self-etch adhesives were used in this study; SE One (SE), Scotchbond™ Universal (SU), BeautiBond Multi (BB), and Bond Force (BF). Flat human dentin surfaces with standardized smear layer were prepared. Smear layer deproteinizing was carried out by the application of 50ppm hypochlorous acid (HOCl) on dentin surface for 15s followed by Accel® (p-toluenesulfinic acid salt) for 5s prior to adhesive application. No surface pretreatment was used as control. Microtensile bond strength (µTBS) and nanoleakage under TEM observation were investigated. The data were analyzed by two-way ANOVA and Tukey's post-hoc test and t-test at the significant level of 0.05. RESULTS: Smear layer deproteinizing significantly improved µTBS of SE, SU, and BB (p<0.001). Hybridized smear layer observed in control groups of SE, BB, and BF, and reticular nanoleakage presented throughout the hybridized complex in control groups of BB and BF were eliminated upon the smear layer deproteinizing. SIGNIFICANCE: Smear layer deproteinizing by HOCl and Accel® application could enhance the quality of dentin for bonding to one-step self-etch adhesives, resulting in the improving µTBS, eliminating hybridized smear layer and preventing reticular nanoleakage formation in resin-dentin bonding interface.


Assuntos
Resinas Compostas/química , Colagem Dentária/métodos , Adesivos Dentinários/química , Dentina/efeitos dos fármacos , Camada de Esfregaço/química , Infiltração Dentária/prevenção & controle , Dentina/química , Humanos , Ácido Hipocloroso , Técnicas In Vitro , Teste de Materiais , Microscopia Eletrônica de Transmissão , Cimentos de Resina , Propriedades de Superfície , Resistência à Tração , Tolueno/análogos & derivados
9.
J Adhes Dent ; 19(3): 253-258, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28580461

RESUMO

PURPOSE: To evaluate the effect of a reducing agent and plant-extract antioxidant on the bonding durability of a self-etch adhesive to normal and NaOCl-treated, smear-layer-deproteinized dentin. MATERIALS AND METHODS: Flat smear-layer-covered dentin surfaces from 60 extracted human molars were prepared by removing the occlusal enamel. The teeth were divided into two groups with or without NaOCl-deproteinizing treatment for 30 s, and further divided into three subgroups as follows: no application of antioxidant, application of Accel (p-toluenesulfinic acid sodium salt solution) for 5 s, or application of rosmarinic acid solution for 5 s. All treated dentin surfaces were bonded with a two-step self-etch adhesive (Clearfil SE Bond) and restored with composite (Clearfil AP-X). The bonded teeth were sectioned into a hourglass-shaped sticks with a composite-dentin bonded interface area of 1.0 mm2. After storage in artificial saliva for 24 h or 1 year, the specimens were subjected to the microtensile bond strength test (n = 15). Data were statistically analyzed with three-way ANOVA, Tukey's post-hoc test, and the t-test (p < 0.05). RESULTS: Without an antioxidant, 1-year storage significantly reduced the bond strengths of the self-etch adhesive to normal and smear-layer-deproteinized dentin compared with those after 24-h storage (p < 0.05). Application of Accel and rosmarinic acid restored the compromised initial bond strengths to smear-layer-deproteinized dentin (p < 0.05), and prevented long-term deterioration of bond strengths to both normal and smear-layer-deproteinized dentin (p > 0.05). CONCLUSION: Application of Accel and rosmarinic acid improved bonding durability of the self-etch adhesive to both normal and smear-layer-deproteinized dentin.


Assuntos
Adesivos Dentinários , Substâncias Redutoras , Antioxidantes , Resinas Compostas , Colagem Dentária , Cimentos Dentários , Dentina , Humanos , Teste de Materiais , Cimentos de Resina , Resistência à Tração
10.
J Adhes Dent ; 18(3): 197-204, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27163111

RESUMO

PURPOSE: To evaluate the effect of a scrubbing technique with one-step self-etching adhesives on bond strengths and nanoleakage expression at the resin/dentin interface. MATERIALS AND METHODS: Flat human dentin surfaces bonded with one of two mild self-etching adhesives, SE One (SE) or Scotchbond Universal (SU) applied either with scrubbing or without scrubbing technique, were prepared (n = 5). The microtensile bond strengths (µTBS), SE micrographs of morphological changes on treated dentin surfaces, and expression of nanoleakage along the bonded dentin interfaces as shown with TEM were evaluated. µTBS data were analyzed using two-way ANOVA and the post-hoc t-test at the significance level of 0.05. RESULTS: The scrubbing technique had a significant positive effect on the µTBS of SU (p < 0.05), while it produced no significant difference for SE (p > 0.05). Morphological evaluation of the treated dentin surfaces demonstrated that SU with scrubbing showed the highest etching ability, followed by scrubbing SE > nonscrubbing SE > nonscrubbing SU. In the nonscrubbing groups, nanoleakage formation using SU exhibited a reticular pattern throughout the hybridized complex, whereas with SE, water-tree nanoleakage was only found in the adhesive layer at dentinal tubule orifices. The scrubbing groups of both adhesives did not exhibit any nanoleakage expression. CONCLUSION: Using a scrubbing technique when applying mild self-etching adhesives could improve resin monomer infiltration into dentin, chase water on adhesive surfaces, and facilitate smear layer removal.


Assuntos
Condicionamento Ácido do Dente/métodos , Colagem Dentária , Infiltração Dentária/classificação , Adesivos Dentinários/química , Adolescente , Adulto , Bis-Fenol A-Glicidil Metacrilato/química , Dentina/ultraestrutura , Humanos , Técnicas In Vitro , Teste de Materiais , Metacrilatos/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanotecnologia , Cimentos de Resina/química , Estresse Mecânico , Propriedades de Superfície , Adulto Jovem
11.
J Dent ; 42(3): 298-304, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24321293

RESUMO

OBJECTIVES: This study aimed to investigate deproteinizing effect of sodium-hypochlorite (NaOCl) and mild acidic hypochlorous-acid (HOCl) pretreatment on smear layer-covered dentine and to evaluate their effects on morphological characteristics of resin-dentine interface with self-etch adhesive. METHODS: Human coronal-dentine discs with standardized smear layer were pretreated with 6% NaOCl or 50ppm HOCl for 15s or 30s. Their deproteinizing effects at the treated smear layer-covered dentine surfaces were determined by the measurement of amide:phosphate ratio using ATR-FTIR analysis. In addition, using TEM, micromorphological alterations of hybridized complex and nanoleakage expression were evaluated at the interface of a self-etch adhesive (Clearfil SE Bond) to the pretreated dentine surface with or without subsequent application of a reducing agent (p-Toluenesulfinic acid salt; Accel(®)). RESULTS: Both pretreatments of NaOCl and HOCl significantly reduced the amide:phosphate ratio as compared with the no-pretreated group (p<0.05), coincident with the elimination of the hybridized smear layer on their bonded interfaces. Nanoleakage within the hybrid layer was found in the no-pretreated and NaOCl-pretreated groups, whereas the subsequent reducing agent application changed the reticular nanoleakage to spotted type. HOCl-pretreated groups showed less nanoleakage expression in a spotted pattern, regardless of reducing agent application. CONCLUSIONS: NaOCl and HOCl solutions could remove the organic component on the smear layer-covered dentine, which could eliminate the hybridized smear layer created by self-etch adhesive, leading to the reduction of nanoleakage expression within hybrid layer. CLINICAL SIGNIFICANCE: Smear layer deproteinizing could modify dentine surface, giving an appropriate substrate for bonding to self-etch adhesive system.


Assuntos
Resinas Compostas/química , Colagem Dentária , Materiais Dentários/química , Dentina/efeitos dos fármacos , Ácido Hipocloroso/uso terapêutico , Cimentos de Resina/química , Irrigantes do Canal Radicular/uso terapêutico , Camada de Esfregaço/tratamento farmacológico , Hipoclorito de Sódio/uso terapêutico , Amidas/análise , Colágeno/análise , Infiltração Dentária/classificação , Dentina/química , Humanos , Teste de Materiais , Microscopia Eletrônica de Transmissão , Fosfatos/análise , Distribuição Aleatória , Substâncias Redutoras/química , Camada de Esfregaço/patologia , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Fatores de Tempo , Tolueno/análogos & derivados , Tolueno/química
12.
Dent Mater J ; 32(6): 992-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24240894

RESUMO

This study investigated the polymerization behavior within the adhesive layer of one- and two-step self-etch adhesives at the dentincomposite interface. Dentin surfaces were applied with Clearfil S(3) Bond (TS), Clearfil S(3) Bond Plus (TSP) and Clearfil SE Bond (SE), and then placed with a light-curing resin composite. After water storage for 24 h, the bonded teeth were sectioned and polished perpendicular to the adhesive interface, and the degree of conversion (DC) of the adhesive layer between the dentin and composite were determined using micro-Raman analysis. For all the adhesives, the DCs of the adhesive layers significantly decreased near the adhesive-composite join (p<0.05). For the maximum DC value (Pmax) and the DC value at the adhesive-composite join (Pitf), TS was significantly lower than TSP and SE (p<0.05). The polymerization of oxygen-inhibited layer at the top of the adhesive could not reach maximum DC even after polymerization of the overlying resin composite.


Assuntos
Condicionamento Ácido do Dente , Cimentos Dentários/química , Polimerização , Análise Espectral Raman/métodos , Cimentos de Resina
13.
Dent Mater J ; 32(4): 615-21, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23903644

RESUMO

This study aimed to evaluate the ability of a newly developed calcium-phosphate desensitizer in dentin permeability reduction and its integration with dentin surface before and after immersion in artificial saliva (AS) under two different dentin surface characteristics; with or without the collagen exposure.Humandentin discs treated by EDTA to expose collagen fibrils or EDTA/NaOCl to expose plain dentin surface were subjected to a calcium-phosphate desensitizer (Teethmate Desensitizer; TMD), while non-desensitizer treatment served as control. TMD application showed the occlusion in dentinal tubules and reduction in dentin permeability up to 92%, regardless of dentin surface characteristics. After AS immersion, permeability reduction percent (PR%) significantly increased in EDTA/NaOCl pretreatment (p<0.05). Newly-formed crystallites were observed on desensitizer treated dentin and EDTA/NaOCl pretreatment control group, whereas the crystallites did not exist on EDTA pretreatment control group. Ultrasonication revealed the integration of the calcium-phosphate rich layer of desensitizer on dentin surface after AS immersion.


Assuntos
Fosfatos de Cálcio/farmacologia , Dessensibilizantes Dentinários/farmacologia , Dentina/efeitos dos fármacos , Quelantes/farmacologia , Colágeno/efeitos dos fármacos , Colágeno/ultraestrutura , Cristalização , Dentina/ultraestrutura , Permeabilidade da Dentina/efeitos dos fármacos , Ácido Edético/farmacologia , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Oxidantes/farmacologia , Saliva Artificial/química , Camada de Esfregaço , Hipoclorito de Sódio/farmacologia , Ultrassom
14.
J Biomed Mater Res B Appl Biomater ; 101(2): 303-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23166091

RESUMO

In the current trend of materials used for dentin hypersensitivity treatment, calcium-phosphate-containing desensitizers are expected to have advantages in oral environment. A newly formulated desensitizer containing tetracalcium phosphate and dicalcium phosphate anhydrous (CPD-100) was evaluated in comparison to oxalate containing desensitizer (SS) regarding permeability reduction (PR%) by measuring hydraulic conductance on the etched dentin discs in vitro. CPD-100 exhibited mean PR% of 91%, which significantly increased to 98% after immersion in artificial saliva (AS) for 4 weeks (p < 0.001), while SS showed a significant decrease from 99% to 93% (p < 0.01). SEM observation showed newly formed crystallites on CPD-100 treated dentin, which did not exist in SS treated dentin after AS immersion, suggesting that calcium oxalate inhibited formation of new calcium-phosphate minerals. Five-minute acid challenge did not significantly affect PR% of dentin treated by any of the desensitizers. The energy dispersive X-ray spectroscopy (EDS) analysis indicated that the formed layer of CPD-100 were minerals with similar Ca/P ratio to hydroxyapatite. In conclusion, the newly developed calcium-phosphate desensitizer has the potential to exhibit long-term stability in the oral environment, owing to its chemical properties that promote the crystal growth in salivary fluid.


Assuntos
Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Dessensibilizantes Dentinários/química , Dessensibilizantes Dentinários/farmacologia , Sensibilidade da Dentina/tratamento farmacológico , Cristalização , Dentina/efeitos dos fármacos , Dentina/patologia , Dentina/fisiopatologia , Permeabilidade da Dentina/efeitos dos fármacos , Permeabilidade da Dentina/fisiologia , Sensibilidade da Dentina/patologia , Sensibilidade da Dentina/fisiopatologia , Humanos , Hidrodinâmica , Técnicas In Vitro , Teste de Materiais , Microscopia Eletrônica de Varredura , Espectrometria por Raios X
15.
J Dent ; 40 Suppl 2: e77-82, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22955005

RESUMO

OBJECTIVE: The purpose of this study was to evaluate the light transmission characteristics of dentine and resin composites with different thickness. METHODS: Disks of bovine dentine and three resin composites (Estelite Σ, Beautifil II and Clearfil Majesty) of OA2 shade were prepared with various thicknesses (0.5, 1.0 and 2.0mm). Using a goniophotometer, the distribution graphs of the light transmission intensity of each specimen were obtained, and diffusion factor (DF) as an indicator for a diffuse transmission property and peak-gain (G0) for a straight-line transmission property were calculated. Their colors were measured on black and white backings using a reflection spectrophotometer to calculate translucency parameter (TP). The data of each value (G0, DF and TP) were analyzed by two-way ANOVA and Dunnett's T3 for post hoc test (p=0.05). Regression analyses were used to determine the correlation between G0, DF, TP values and the thickness. RESULTS: Regardless of the thickness, dentine had lower TP values than the resin composites. 0.5 mm-thick specimens of dentine and resin composite produced various G0 and DF values, with dentine exhibiting significantly lower G0 and higher DF than the resin composites (p<0.05), whereas with the 1.0 and 2.0mm-thick specimens, they were closely aligned. For dentine, G0 and DF increased in inverse proportion to the thickness (G0: R(2)=0.962, p<0.001; DF: R(2)=0.891, p<0.001). CONCLUSIONS: Dentine had different light transmission characteristics from resin composite, depending on the thickness. CLINICAL SIGNIFICANCE: Dentine has different light transmission characteristics (straight-line and diffusion) from resin composite, depending on thickness. Resin composite restoration might be different to accurately reproduce light transmission characteristics of dentine substrate.


Assuntos
Resinas Compostas/química , Materiais Dentários/química , Dentina/anatomia & histologia , Algoritmos , Animais , Bis-Fenol A-Glicidil Metacrilato/química , Bis-Fenol A-Glicidil Metacrilato/efeitos da radiação , Bovinos , Cor , Resinas Compostas/efeitos da radiação , Materiais Dentários/efeitos da radiação , Dentina/efeitos da radiação , Luz , Fotometria , Espectrofotometria , Propriedades de Superfície
16.
J Adhes Dent ; 14(2): 121-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22282742

RESUMO

PURPOSE: To evaluate the scrubbing effect of self-etching adhesive systems on the microtensile bond strengths to sodium hypochlorite-treated dentin. MATERIALS AND METHODS: The occlusal surfaces of 36 extracted human third molars were horizontally cut to expose sound dentin. The dentin surfaces of the teeth were treated with 6% NaOCl aqueous solution for 30 s or none. After water rinsing for 10 s and air drying, a 2-step (Clearfil Protect Bond) or 1-step (Clearfil S3 Bond or Bond Force) self-etching adhesive was applied with or without a scrubbing technique, and resin composite (Clearfil AP-X) crowns were built up. The bonded specimens were stored in water for 24 h and then subjected to the microtensile bond test at a crosshead speed of 1.0 mm/min. Data were analyzed using three-way ANOVA and Bonferroni multiple comparisons (p < 0.05). RESULTS: The NaOCl-treated dentin exhibited significantly lower bond strength with the tested self-etching adhesive systems than did the normal dentin (p < 0.05). Using a scrubbing technique for the tested self-etching adhesive systems significantly improved the µTBS to NaOCl-treated dentin (p < 0.05), whereas there was no significant difference in µTBS to normal dentin between a scrubbing and nonscrubbing technique (p > 0.05). CONCLUSION: Using a scrubbing technique for applying self-etching adhesive systems to NaOCl-treated dentin was effective in improving the compromised bonding.


Assuntos
Colagem Dentária , Adesivos Dentinários , Dentina/efeitos dos fármacos , Irrigantes do Canal Radicular/farmacologia , Hipoclorito de Sódio/farmacologia , Condicionamento Ácido do Dente , Análise de Variância , Análise do Estresse Dentário , Permeabilidade da Dentina , Fricção , Humanos , Teste de Materiais , Camada de Esfregaço , Estatísticas não Paramétricas , Resistência à Tração
17.
Dent Mater ; 27(3): 229-34, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21074250

RESUMO

OBJECTIVE: The purpose of this study was to evaluate the effect of three antioxidant/reducing agents with different application times on microtensile bond strengths to sodium hypochlorite-treated dentin. METHODS: The occlusal surfaces of 24 extracted human third molars were horizontally cut to expose sound dentin. The teeth were divided into eight groups. The dentin surfaces of the teeth were treated as follows: group 1, no treatment; group 2, treated with 6% sodium hypochlorite (NaOCl) for 30s; groups 3-8, applications of 10% sodium ascorbate solution, 100 µM rosmarinic acid solution or Accel for 5 or 10s after the same treatment as in group 2. All treated dentin surfaces were bonded with a 2-step self-etching adhesive system (Clearfil Protect Bond) and restored with a resin composite (Clearfil AP-X). After storage in water for 24h, the bonded specimens were subjected to the microtensile bond test at a crosshead speed of 1.0 mm/min. Data were analyzed by a one-way ANOVA and Tukey test (p<0.05). RESULTS: The NaOCl-treated group had significantly lower bond strength than the control group (p<0.05). The application of sodium ascorbate solution for 5 or 10s did not significantly increase the compromised bonding to NaOCl-treated dentin (p>0.05). On the other hand, Accel and rosmarinic acid solution had significant reversal effects with the same application times (p<0.05). SIGNIFICANCE: The reversal effect on compromised bonding to NaOCl-treated dentin depended upon the type of antioxidant within the short application time. Applying Accel or rosmarinic acid for 5 or 10s improved bond strengths to NaOCl-treated dentin.


Assuntos
Antioxidantes , Cinamatos , Colagem Dentária , Adesivos Dentinários , Dentina/efeitos dos fármacos , Depsídeos , Irrigantes do Canal Radicular/farmacologia , Hipoclorito de Sódio/farmacologia , Análise de Variância , Ácido Ascórbico , Cinamatos/química , Resinas Compostas , Restauração Dentária Permanente/métodos , Análise do Estresse Dentário , Depsídeos/química , Humanos , Peróxido de Hidrogênio , Teste de Materiais , Metacrilatos , Substâncias Redutoras , Cimentos de Resina , Estatísticas não Paramétricas , Resistência à Tração
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