PURPOSE To evaluate the effects of a carbamide peroxide bleaching agent on interfaces formed by t... more PURPOSE To evaluate the effects of a carbamide peroxide bleaching agent on interfaces formed by two one-bottle dental adhesives to etched enamel. The null hypotheses tested in this study were that vital bleaching with a commercial 10% carbamide peroxide gel would not (1) increase the concentration of oxygen in the superficial layer of enamel or (2) induce ultra-morphological changes in resin-enamel interfaces. MATERIALS AND METHODS Five extracted human incisors were treated with 10% carbamide peroxide (Opalescence) for 4 h/day for 1 week and were compared with non-bleached teeth for oxygen, calcium, and phosphorus relative concentration using EDS. Mean elemental concentrations were analyzed using a t-test (bleached vs. unbleached enamel), one-way ANOVA (for surface location and also for depth) and three-way ANOVA (with bleaching treatment, surface location, and depth as the main factors). For TEM, fifteen extracted human molars were sectioned to obtain two crown halves. After roughe...
Current dental restorative materials include tooth-colored materials called composite resins, whi... more Current dental restorative materials include tooth-colored materials called composite resins, which are made of a resin matrix and an inorganic filler coated with a silane coupling agent. Composite resins can shrink considerably upon setting. This shrinkage stress can generate gaps along the composite/dentin interface. Low-viscosity fluid resins and primers have been used to bond composite resins to dentin. The adhesive resin layer may be able to act as an elastic medium and compensate for the polymerization stresses that develop within the composite resin. The hypothesis tested in this study was that the use of a “stress-absorbing” intermediary dentin adhesive would result in lower incidence of gaps at the restoration/cavity interface and in a thicker resin/dentin interdifusion layer or hybrid layer.Dentin disks with a thickness of 900 um±100 μm were obtained from extracted human molars and assigned to two adhesive systems (One-Step [OS] and Single Bond [SB]), three degrees of inte...
Volumetric Shrinkage and Conversion of Low-Stress Flowable Dental Composites Objective: Recently,... more Volumetric Shrinkage and Conversion of Low-Stress Flowable Dental Composites Objective: Recently, low-stress restorative technologies have been developed, both as regular consistency pastes and easier to place flowable materials, which have been proposed as bulk-fill composites. This study analyzes such materials compared to their conventional analogs in terms of their shrinkage and conversion, important determinants to final mechanical properties and stress development. Methods: Six composites were selected: Venus Diamond (VD) and EsthetXHD (EHD) as the conventional controls, Venus Diamond flow (VDF) and EsthetX flow (ESF) as conventional flowable composites, and Venus Bulk Fill (VBF) and Surefil SDR flow (SDR) as low-stress flowable composites. Volumetric shrinkage (VS, n=3) was determined in a linometer (ACTA) for 30min. Specimens (6mm x 1.5mm) were photoactivated (740mW/cm2) for 27s. Conversion (DC) was determined on the same specimens right after the linometer run in near-IR (6...
Moisture/Temperature Effects on Cationic/Radical Dental Composite Polymerizations Objective: Anal... more Moisture/Temperature Effects on Cationic/Radical Dental Composite Polymerizations Objective: Analyze the influence of ambient conditions, such as oral cavity humidity/temperature on polymerization of dimethacrylate or oxirane-based dental composites. Methods: 250m films of EsthetXHD (EHD, dimethacrylate) or FiltekP90 (P90, oxirane-based) were allowed to saturate at 85% relative humidity before being sealed between glass slides (0.8mm thick, n=3). Unmodified composites were used as controls. Specimens were polymerized (Acticure, 320-500nm, 200mW/cm2) on a custom-designed heated stage fitted to a FT-IR spectrometer chamber at 23, 35 or 60C. Photopolymerization was monitored in real-time for 10min. Degree of Conversion (DCmax) and rate of polymerization (Rp) were calculated based on the absorption bands at 6165 and 4155cm-1 for EHD and P90, respectively. Results were analyzed with one-way ANOVA/Tukey's test (α=5%). Results: Results are shown in the Table (same superscript within a ...
Technological advances lead to a new perspective of learning tools. In the East, it’s common to u... more Technological advances lead to a new perspective of learning tools. In the East, it’s common to use reminder cards as study tools during idle time. The need of maximize study time has comming to modernity as "flashcards", ie softwares with the format of questions and answers, followed by images or caption for the fixation of concepts. The software called Anki (www.ankisrs.net) is free available with open source and customizable, works linking the level of difficulty of concepts remembering (rated by the user as: 1-repeat 2-good, 3-easy or 4 - difficult) to the time of repeating the same content. Objectives: Considering the common use of notebooks, tablets, smartphones and related technologies in the classroom, the aim of this study was to evaluate the new horizon from digital knowledge as a method of teaching and learning in dental materials. Methods: After the professors from FOUSP determined conceptual issues on dentin bonding strength, forty students (40) from 1st to 3r...
Objectives: To evaluate fourteen LEDs and their temperature increase on tips. Methods: The light ... more Objectives: To evaluate fourteen LEDs and their temperature increase on tips. Methods: The light emitting diodes used were Smart Lite, Dentsply (SL); Radii Plus, SDI (RP); Elipar Freelight 2, 3M ESPE (EP); LE Demetron, Demetron (LD); Celalux, Voco (CL); Ultralume 5, Ultradent (UT); Bluephase G2, Ivoclar (BP); Flashlite, Discus (FL); Ultralight III, Sanders (UL); LEC 470II, MM Optics (LE); Biolux, Bioart (BL); Ultra Blue, DMC (UB); Blue Star, Microdont (BS) and Mais, New Image (MS) compared to QTH,Optilux 501, Demetron (OP). The composite used was Herculite XRV, A2 enamel shade, light cured for 40s. The irradiance were verified in a radiometer (L.E.D. Radiometer, Kerr) and characterized with spectroradiometer (Ocean Optics 1000) coupled to a microprocessor NOVA. The temperature increase of the light sources was verified with digital thermometer using thermocouples K. The mean values of temperature increase were submitted to the ANOVA and Tukey post hoc test (a=.05). Results: The maxi...
Revista Portuguesa de Estomatologia, Medicina Dentária e Cirurgia Maxilofacial, 2015
Objective: To evaluate the effect of the application modes and the presence of filler of etchand-... more Objective: To evaluate the effect of the application modes and the presence of filler of etchand-rinse adhesive systems on the micro-shear bond strength test (SBS) to bovine dentin. Methods: Twenty bovine teeth had the enamel removed and dentin surface exposed. Dentin was etched with 37% phosphoric acid and the following adhesive systems were applied: One Step and One Step Plus with two modes (no rubbing action and vigorous rubbing action). To each tooth six Tygon cylinders with internal 0.76 mm were filled with flowable composite resin. All cylinders were light polymerized for 40 s (Optilux 501). The SBS was performed in a universal testing machine (Instron 5565), with specimens held in place by a wire (0.2 mm) loop, and force loaded to failure. The fracture mode was evaluated. The results in MPa were statistically analyzed by two-way ANOVA and Holm-Sidak tests (˛ = 0.05). Results: The two-way ANOVA detected no interactions between factors (p = 0.865), but only differences between the adhesive systems (p = 0.042) and application modes (p = 0.014). One Step Plus obtained a higher SBS than One Step, and vigorous application increased bond strength of adhesives systems. The predominant failure modes of all groups were adhesivemixed. Conclusion: The adhesive systems showed the best SBS results with presence of filler and active mode application.
To evaluate in vitro the microshear bond strength of adhesive systems applied to dentin according... more To evaluate in vitro the microshear bond strength of adhesive systems applied to dentin according to manufacturers' instructions, associated or not with a hydrophobic layer of unfilled resin. Six self-etching adhesives (Clearfil SE Bond, Kuraray Medical; AdheSE, Ivoclar Vivadent; Xeno III, Dentsply; I Bond, Heraeus-Kulzer; Bond Force, Tokuyama; Futurabond DC, Voco) were tested. The labial dentin of sixty bovine incisors was exposed, and the teeth were divided into two groups according to the application or not of an extra hydrophobic resin layer (Scotchbond Multi Purpose Plus, bottle 3). Six composite cylinders (Filtek Z250, 3M ESPE) were built up on each treated surface. Specimens were stored in distilled water at 37ºC for 24 h and then subjected to the microshear bond strength test in a universal testing machine at a crosshead speed of 0.5 mm/min. Microshear bond strength values were analyzed by 2-way ANOVA and Tukey's post-hoc test. Failure mode was determined using a ste...
To investigate the in vitro performance of three one-bottle adhesives by measuring their dentin m... more To investigate the in vitro performance of three one-bottle adhesives by measuring their dentin microtensile strength. Extracted human molars had the dentin exposed on the occlusal surface. The teeth were randomly assigned to three dentin adhesives: Group 1 - Prime & Bond 2.1; Group 2 - Prime & Bond NT; and Group 3 - Experimental (unfilled NT). All materials were applied as recommended by the manufacturer. A high-density resin composite (Surefil) was packed on the bonding area in five increments. Specimens (sticks) were obtained using a diamond disc and were stored in distilled water for 24 hrs. The microtensile bond strengths were measured with a universal testing machine. Group 1: 54.3+/-15.6 MPa; Group 2: 62.0+/-17.6 MPa; Group 3: 54.6+/-16.8 MPa. Although no statistically significant difference was found between pairs of means, Prime&Bond NT showed a tendency for higher bond strengths.
To evaluate microleakage at enamel and dentin margins of Class V resin-based composite (RBC) rest... more To evaluate microleakage at enamel and dentin margins of Class V resin-based composite (RBC) restorations using five simplified adhesive systems, one self-etching adhesive, three commercial one-bottle adhesives and one experimental one-bottle adhesive. Class V cavities (3 mm x 2 mm x 2 mm) were prepared in sound human molars with occlusal margins in enamel and gingival margins in dentin/cementum. Etch & Prime 3.0 (Degussa), Single Bond (3M), PQ1 (Ultradent), Prime & Bond NT (Dentsply) and Experimental BEH (Dentsply DeTrey) were applied strictly according to manufacturers instructions. All adhesive systems were applied on etched substrates, except for the self-etching adhesive Etch & Prime 3.0. Cavities were restored with Z100 RBC. After finishing and polishing, teeth were thermo-cycled (x 700, 5-55 degrees C, 60 s dwell time). Specimens were coated with nail varnish, immersed in silver nitrate for 2 hours and sectioned longitudinally with a diamond disc. The extent of leakage was me...
To evaluate the effects of a carbamide peroxide bleaching agent on interfaces formed by two one-b... more To evaluate the effects of a carbamide peroxide bleaching agent on interfaces formed by two one-bottle dental adhesives to etched enamel. The null hypotheses tested in this study were that vital bleaching with a commercial 10% carbamide peroxide gel would not (1) increase the concentration of oxygen in the superficial layer of enamel or (2) induce ultra-morphological changes in resin-enamel interfaces. Five extracted human incisors were treated with 10% carbamide peroxide (Opalescence) for 4 h/day for 1 week and were compared with non-bleached teeth for oxygen, calcium, and phosphorus relative concentration using EDS. Mean elemental concentrations were analyzed using a t-test (bleached vs. unbleached enamel), one-way ANOVA (for surface location and also for depth) and three-way ANOVA (with bleaching treatment, surface location, and depth as the main factors). For TEM, fifteen extracted human molars were sectioned to obtain two crown halves. After roughening the occlusal surface, one...
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2006
Changes of elementary concentrations in dental enamel after a bleaching treatment with different ... more Changes of elementary concentrations in dental enamel after a bleaching treatment with different products, is presented, with special focus on the oxygen contribution. Concentrations for Ca, P, O and C and some other trace elements were obtained for enamel of bovine incisor teeth by HI-ERDA measurements using a 35Cl incident beam and an ionization chamber. Five groups of teeth with
PURPOSE To evaluate the effects of a carbamide peroxide bleaching agent on interfaces formed by t... more PURPOSE To evaluate the effects of a carbamide peroxide bleaching agent on interfaces formed by two one-bottle dental adhesives to etched enamel. The null hypotheses tested in this study were that vital bleaching with a commercial 10% carbamide peroxide gel would not (1) increase the concentration of oxygen in the superficial layer of enamel or (2) induce ultra-morphological changes in resin-enamel interfaces. MATERIALS AND METHODS Five extracted human incisors were treated with 10% carbamide peroxide (Opalescence) for 4 h/day for 1 week and were compared with non-bleached teeth for oxygen, calcium, and phosphorus relative concentration using EDS. Mean elemental concentrations were analyzed using a t-test (bleached vs. unbleached enamel), one-way ANOVA (for surface location and also for depth) and three-way ANOVA (with bleaching treatment, surface location, and depth as the main factors). For TEM, fifteen extracted human molars were sectioned to obtain two crown halves. After roughe...
Current dental restorative materials include tooth-colored materials called composite resins, whi... more Current dental restorative materials include tooth-colored materials called composite resins, which are made of a resin matrix and an inorganic filler coated with a silane coupling agent. Composite resins can shrink considerably upon setting. This shrinkage stress can generate gaps along the composite/dentin interface. Low-viscosity fluid resins and primers have been used to bond composite resins to dentin. The adhesive resin layer may be able to act as an elastic medium and compensate for the polymerization stresses that develop within the composite resin. The hypothesis tested in this study was that the use of a “stress-absorbing” intermediary dentin adhesive would result in lower incidence of gaps at the restoration/cavity interface and in a thicker resin/dentin interdifusion layer or hybrid layer.Dentin disks with a thickness of 900 um±100 μm were obtained from extracted human molars and assigned to two adhesive systems (One-Step [OS] and Single Bond [SB]), three degrees of inte...
Volumetric Shrinkage and Conversion of Low-Stress Flowable Dental Composites Objective: Recently,... more Volumetric Shrinkage and Conversion of Low-Stress Flowable Dental Composites Objective: Recently, low-stress restorative technologies have been developed, both as regular consistency pastes and easier to place flowable materials, which have been proposed as bulk-fill composites. This study analyzes such materials compared to their conventional analogs in terms of their shrinkage and conversion, important determinants to final mechanical properties and stress development. Methods: Six composites were selected: Venus Diamond (VD) and EsthetXHD (EHD) as the conventional controls, Venus Diamond flow (VDF) and EsthetX flow (ESF) as conventional flowable composites, and Venus Bulk Fill (VBF) and Surefil SDR flow (SDR) as low-stress flowable composites. Volumetric shrinkage (VS, n=3) was determined in a linometer (ACTA) for 30min. Specimens (6mm x 1.5mm) were photoactivated (740mW/cm2) for 27s. Conversion (DC) was determined on the same specimens right after the linometer run in near-IR (6...
Moisture/Temperature Effects on Cationic/Radical Dental Composite Polymerizations Objective: Anal... more Moisture/Temperature Effects on Cationic/Radical Dental Composite Polymerizations Objective: Analyze the influence of ambient conditions, such as oral cavity humidity/temperature on polymerization of dimethacrylate or oxirane-based dental composites. Methods: 250m films of EsthetXHD (EHD, dimethacrylate) or FiltekP90 (P90, oxirane-based) were allowed to saturate at 85% relative humidity before being sealed between glass slides (0.8mm thick, n=3). Unmodified composites were used as controls. Specimens were polymerized (Acticure, 320-500nm, 200mW/cm2) on a custom-designed heated stage fitted to a FT-IR spectrometer chamber at 23, 35 or 60C. Photopolymerization was monitored in real-time for 10min. Degree of Conversion (DCmax) and rate of polymerization (Rp) were calculated based on the absorption bands at 6165 and 4155cm-1 for EHD and P90, respectively. Results were analyzed with one-way ANOVA/Tukey's test (α=5%). Results: Results are shown in the Table (same superscript within a ...
Technological advances lead to a new perspective of learning tools. In the East, it’s common to u... more Technological advances lead to a new perspective of learning tools. In the East, it’s common to use reminder cards as study tools during idle time. The need of maximize study time has comming to modernity as "flashcards", ie softwares with the format of questions and answers, followed by images or caption for the fixation of concepts. The software called Anki (www.ankisrs.net) is free available with open source and customizable, works linking the level of difficulty of concepts remembering (rated by the user as: 1-repeat 2-good, 3-easy or 4 - difficult) to the time of repeating the same content. Objectives: Considering the common use of notebooks, tablets, smartphones and related technologies in the classroom, the aim of this study was to evaluate the new horizon from digital knowledge as a method of teaching and learning in dental materials. Methods: After the professors from FOUSP determined conceptual issues on dentin bonding strength, forty students (40) from 1st to 3r...
Objectives: To evaluate fourteen LEDs and their temperature increase on tips. Methods: The light ... more Objectives: To evaluate fourteen LEDs and their temperature increase on tips. Methods: The light emitting diodes used were Smart Lite, Dentsply (SL); Radii Plus, SDI (RP); Elipar Freelight 2, 3M ESPE (EP); LE Demetron, Demetron (LD); Celalux, Voco (CL); Ultralume 5, Ultradent (UT); Bluephase G2, Ivoclar (BP); Flashlite, Discus (FL); Ultralight III, Sanders (UL); LEC 470II, MM Optics (LE); Biolux, Bioart (BL); Ultra Blue, DMC (UB); Blue Star, Microdont (BS) and Mais, New Image (MS) compared to QTH,Optilux 501, Demetron (OP). The composite used was Herculite XRV, A2 enamel shade, light cured for 40s. The irradiance were verified in a radiometer (L.E.D. Radiometer, Kerr) and characterized with spectroradiometer (Ocean Optics 1000) coupled to a microprocessor NOVA. The temperature increase of the light sources was verified with digital thermometer using thermocouples K. The mean values of temperature increase were submitted to the ANOVA and Tukey post hoc test (a=.05). Results: The maxi...
Revista Portuguesa de Estomatologia, Medicina Dentária e Cirurgia Maxilofacial, 2015
Objective: To evaluate the effect of the application modes and the presence of filler of etchand-... more Objective: To evaluate the effect of the application modes and the presence of filler of etchand-rinse adhesive systems on the micro-shear bond strength test (SBS) to bovine dentin. Methods: Twenty bovine teeth had the enamel removed and dentin surface exposed. Dentin was etched with 37% phosphoric acid and the following adhesive systems were applied: One Step and One Step Plus with two modes (no rubbing action and vigorous rubbing action). To each tooth six Tygon cylinders with internal 0.76 mm were filled with flowable composite resin. All cylinders were light polymerized for 40 s (Optilux 501). The SBS was performed in a universal testing machine (Instron 5565), with specimens held in place by a wire (0.2 mm) loop, and force loaded to failure. The fracture mode was evaluated. The results in MPa were statistically analyzed by two-way ANOVA and Holm-Sidak tests (˛ = 0.05). Results: The two-way ANOVA detected no interactions between factors (p = 0.865), but only differences between the adhesive systems (p = 0.042) and application modes (p = 0.014). One Step Plus obtained a higher SBS than One Step, and vigorous application increased bond strength of adhesives systems. The predominant failure modes of all groups were adhesivemixed. Conclusion: The adhesive systems showed the best SBS results with presence of filler and active mode application.
To evaluate in vitro the microshear bond strength of adhesive systems applied to dentin according... more To evaluate in vitro the microshear bond strength of adhesive systems applied to dentin according to manufacturers' instructions, associated or not with a hydrophobic layer of unfilled resin. Six self-etching adhesives (Clearfil SE Bond, Kuraray Medical; AdheSE, Ivoclar Vivadent; Xeno III, Dentsply; I Bond, Heraeus-Kulzer; Bond Force, Tokuyama; Futurabond DC, Voco) were tested. The labial dentin of sixty bovine incisors was exposed, and the teeth were divided into two groups according to the application or not of an extra hydrophobic resin layer (Scotchbond Multi Purpose Plus, bottle 3). Six composite cylinders (Filtek Z250, 3M ESPE) were built up on each treated surface. Specimens were stored in distilled water at 37ºC for 24 h and then subjected to the microshear bond strength test in a universal testing machine at a crosshead speed of 0.5 mm/min. Microshear bond strength values were analyzed by 2-way ANOVA and Tukey's post-hoc test. Failure mode was determined using a ste...
To investigate the in vitro performance of three one-bottle adhesives by measuring their dentin m... more To investigate the in vitro performance of three one-bottle adhesives by measuring their dentin microtensile strength. Extracted human molars had the dentin exposed on the occlusal surface. The teeth were randomly assigned to three dentin adhesives: Group 1 - Prime & Bond 2.1; Group 2 - Prime & Bond NT; and Group 3 - Experimental (unfilled NT). All materials were applied as recommended by the manufacturer. A high-density resin composite (Surefil) was packed on the bonding area in five increments. Specimens (sticks) were obtained using a diamond disc and were stored in distilled water for 24 hrs. The microtensile bond strengths were measured with a universal testing machine. Group 1: 54.3+/-15.6 MPa; Group 2: 62.0+/-17.6 MPa; Group 3: 54.6+/-16.8 MPa. Although no statistically significant difference was found between pairs of means, Prime&Bond NT showed a tendency for higher bond strengths.
To evaluate microleakage at enamel and dentin margins of Class V resin-based composite (RBC) rest... more To evaluate microleakage at enamel and dentin margins of Class V resin-based composite (RBC) restorations using five simplified adhesive systems, one self-etching adhesive, three commercial one-bottle adhesives and one experimental one-bottle adhesive. Class V cavities (3 mm x 2 mm x 2 mm) were prepared in sound human molars with occlusal margins in enamel and gingival margins in dentin/cementum. Etch & Prime 3.0 (Degussa), Single Bond (3M), PQ1 (Ultradent), Prime & Bond NT (Dentsply) and Experimental BEH (Dentsply DeTrey) were applied strictly according to manufacturers instructions. All adhesive systems were applied on etched substrates, except for the self-etching adhesive Etch & Prime 3.0. Cavities were restored with Z100 RBC. After finishing and polishing, teeth were thermo-cycled (x 700, 5-55 degrees C, 60 s dwell time). Specimens were coated with nail varnish, immersed in silver nitrate for 2 hours and sectioned longitudinally with a diamond disc. The extent of leakage was me...
To evaluate the effects of a carbamide peroxide bleaching agent on interfaces formed by two one-b... more To evaluate the effects of a carbamide peroxide bleaching agent on interfaces formed by two one-bottle dental adhesives to etched enamel. The null hypotheses tested in this study were that vital bleaching with a commercial 10% carbamide peroxide gel would not (1) increase the concentration of oxygen in the superficial layer of enamel or (2) induce ultra-morphological changes in resin-enamel interfaces. Five extracted human incisors were treated with 10% carbamide peroxide (Opalescence) for 4 h/day for 1 week and were compared with non-bleached teeth for oxygen, calcium, and phosphorus relative concentration using EDS. Mean elemental concentrations were analyzed using a t-test (bleached vs. unbleached enamel), one-way ANOVA (for surface location and also for depth) and three-way ANOVA (with bleaching treatment, surface location, and depth as the main factors). For TEM, fifteen extracted human molars were sectioned to obtain two crown halves. After roughening the occlusal surface, one...
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2006
Changes of elementary concentrations in dental enamel after a bleaching treatment with different ... more Changes of elementary concentrations in dental enamel after a bleaching treatment with different products, is presented, with special focus on the oxygen contribution. Concentrations for Ca, P, O and C and some other trace elements were obtained for enamel of bovine incisor teeth by HI-ERDA measurements using a 35Cl incident beam and an ionization chamber. Five groups of teeth with
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