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1.
J Appl Oral Sci ; 28: e20190720, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32428059

RESUMEN

Objective This study evaluated the clinical effect of violet LED light on in-office bleaching used alone or combined with 37% carbamide peroxide (CP) or 35% hydrogen peroxide (HP). Methodology A total of 100 patients were divided into five groups (n=20): LED, LED/CP, CP, LED/HP and HP. Colorimetric evaluation was performed using a spectrophotometer (ΔE, ΔL, Δa, Δb) and a visual shade guide (ΔSGU). Calcium (Ca)/phosphorous (P) ratio was quantified in the enamel microbiopsies. Measurements were performed at baseline (T 0 ), after bleaching (T B ) and in the 14-day follow-up (T 14 ). At each bleaching session, a visual scale determined the absolute risk (AR) and intensity of tooth sensitivity (TS). Data were evaluated by one-way (ΔE, Δa, ΔL, Δb), two-way repeated measures ANOVA (Ca/P ratio), and Tukey post-hoc tests. ΔSGU and TS were evaluated by Kruskal-Wallis and Mann-Whitney, and AR by Chi-Squared tests (a=5%). Results LED produced the lowest ΔE (p<0.05), but LED/HP promoted greater ΔE, ΔSGU and Δb (T 14 ) than HP (p<0.05). No differences were observed in ΔE and ΔSGU for LED/CP and HP groups (p>0.05). ΔL and Δa were not influenced by LED activation. After bleaching, LED/CP exhibited greater Δb than CP (p>0.05), but no differences were found between these groups at T 14 (p>0.05). LED treatment promoted the lowest risk of TS (16%), while HP promoted the highest (94.4%) (p<0.05). No statistical differences of risk of TS were found for CP (44%), LED/CP (61%) and LED/HP (88%) groups (p>0.05). No differences were found in enamel Ca/P ratio among treatments, regardless of evaluation times. Conclusions Violet LED alone produced the lowest bleaching effect, but enhanced HP bleaching results. Patients treated with LED/CP reached the same efficacy of HP, with reduced risk and intensity of tooth sensitivity and none of the bleaching protocols adversely affected enamel mineral content.


Asunto(s)
Peróxido de Carbamida/administración & dosificación , Peróxido de Hidrógeno/administración & dosificación , Luz , Fototerapia/métodos , Blanqueadores Dentales/administración & dosificación , Blanqueamiento de Dientes/métodos , Adolescente , Adulto , Análisis de Varianza , Colorimetría , Terapia Combinada , Esmalte Dental/efectos de los fármacos , Esmalte Dental/efectos de la radiación , Sensibilidad de la Dentina/inducido químicamente , Femenino , Humanos , Masculino , Valores de Referencia , Factores de Riesgo , Espectrofotometría , Estadísticas no Paramétricas , Propiedades de Superficie/efectos de los fármacos , Propiedades de Superficie/efectos de la radiación , Resultado del Tratamiento , Adulto Joven
2.
J Appl Oral Sci ; 28: e20190693, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32401940

RESUMEN

Debonding, staining and wear are usually the reasons for denture teeth replacement by new ones from same or different brands. Objective This study investigates the possible differences in color of denture teeth of the same or different brands under different illuminations, since their metameric behavior in color under specific illumination may become unacceptable. Methodology For the purpose of this study, 10 denture teeth (#11), shade A3, of 4 different brands were selected (Creopal/KlemaDental Pro, Executive/DeguDent, Cosmo HXL/DeguDent, Ivostar/Ivoclar-Vivadent). Teeth stabilized in white silicone mold and the CIELAB color coordinates of their labial surface under 3 different illumination lights (D65, F2, A) were recorded, using a portable colorimeter (FRU/WR-18, Wave Inc). ΔE*ab values of all possible pairs of teeth of the same brand (n=45) or pair combinations of different brands (n=100) under each illumination light, in a dry and wet state were calculated. Data were analyzed statistically using 3-way ANOVA, Friedman's and Wilcoxon's tests at a significance level of α=0.05. Results The results showed that brand type affected significantly L*, a* and b* coordinates (p<0.0001), illumination a* and b* coordinates (p<0.0001), but none of them was affected by the hydration state of teeth (p>0.05). Intra-brand color differences ranged between 0.21-0.78ΔΕ* units with significant differences among brands (p<0.0001), among illumination lights (p<0.0001) and between hydration states (p=0.0001). Inter-brand differences ranged between 2.29-6.29ΔΕ* units with significant differences among pairs of brands (p<0.0001), illumination lights (p<0.0001) and hydration states (p<0.0001). Conclusions Differences were found between and within brands under D65 illumination which increased under F2 or A illumination affected by brand type and hydration status. Executive was the most stable brand than the others under different illuminations or wet states and for this reason its difference from other brands is the lowest. In clinical practice, there should be no blending of teeth of different brands but if we must, we should select those that are more stable under different illuminations.


Asunto(s)
Dentaduras , Iluminación , Coloración de Prótesis , Análisis de Varianza , Colorimetría , Humanos , Ensayo de Materiales , Valores de Referencia , Estadísticas no Paramétricas , Propiedades de Superficie/efectos de la radiación
3.
Braz Oral Res ; 34: e005, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32022224

RESUMEN

The purpose of this study was to evaluate the effect of ionizing radiation from high energy X-ray on fluoride release, surface roughness, flexural strength, and surface chemical composition of the materials. The study groups comprised five different restorative materials: Beautifil II, GCP Glass Fill, Amalgomer CR, Zirconomer, and Fuji IX GP. Twenty disk-shaped specimens (8x2 mm) for fluoride release and 20 bar-shaped specimens (25 x 2x 2 mm) for flexural strength were prepared from each material. Each material group was divided into two subgroups: irradiated (IR) and non-irradiated (Non-IR). The specimens from IR groups were irradiated with 1.8 Gy/day for 39 days (total IR = 70.2 Gy). The amount of fluoride released into deionized water was measured using a fluoride ion-selective electrode and ion analyzer after 24 hours and on days 2, 3, 7, 15, 21, 28, 35, and 39 (n = 10). The flexural strength was evaluated using the three-point bending test (n = 10). After the period of measurement of fluoride release, seven specimens (n = 7) from each group were randomly selected to evaluate surface roughness using AFM and one specimen was randomly selected for the SEM and EDS analyses. Data were analyzed with two-way ANOVA and Tukey tests (p = 0.05). The irradiation significantly increased fluoride release and surface roughness for Amalgomer CR and Zirconomer groups (p < 0.05). No significant change in flexural strength of the materials was observed after irradiation (p > 0.05). The ionizing radiation altered the amount of fluoride release and surface roughness of only Amalgomer CR and Zirconomer. The effect could be related to the chemical compositions of materials.


Asunto(s)
Apatitas/efectos de la radiación , Bisfenol A Glicidil Metacrilato/efectos de la radiación , Resinas Compuestas/efectos de la radiación , Fluoruros/química , Cementos de Ionómero Vítreo/efectos de la radiación , Radiación Ionizante , Circonio/efectos de la radiación , Análisis de Varianza , Apatitas/química , Bisfenol A Glicidil Metacrilato/química , Resinas Compuestas/química , Resistencia Flexional , Cementos de Ionómero Vítreo/química , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Valores de Referencia , Reproducibilidad de los Resultados , Espectrometría por Rayos X , Estadísticas no Paramétricas , Propiedades de Superficie/efectos de la radiación , Factores de Tiempo , Circonio/química
4.
Braz. oral res. (Online) ; 34: e005, 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1055521

RESUMEN

Abstract The purpose of this study was to evaluate the effect of ionizing radiation from high energy X-ray on fluoride release, surface roughness, flexural strength, and surface chemical composition of the materials. The study groups comprised five different restorative materials: Beautifil II, GCP Glass Fill, Amalgomer CR, Zirconomer, and Fuji IX GP. Twenty disk-shaped specimens (8x2 mm) for fluoride release and 20 bar-shaped specimens (25 x 2x 2 mm) for flexural strength were prepared from each material. Each material group was divided into two subgroups: irradiated (IR) and non-irradiated (Non-IR). The specimens from IR groups were irradiated with 1.8 Gy/day for 39 days (total IR = 70.2 Gy). The amount of fluoride released into deionized water was measured using a fluoride ion-selective electrode and ion analyzer after 24 hours and on days 2, 3, 7, 15, 21, 28, 35, and 39 (n = 10). The flexural strength was evaluated using the three-point bending test (n = 10). After the period of measurement of fluoride release, seven specimens (n = 7) from each group were randomly selected to evaluate surface roughness using AFM and one specimen was randomly selected for the SEM and EDS analyses. Data were analyzed with two-way ANOVA and Tukey tests (p = 0.05). The irradiation significantly increased fluoride release and surface roughness for Amalgomer CR and Zirconomer groups (p < 0.05). No significant change in flexural strength of the materials was observed after irradiation (p > 0.05). The ionizing radiation altered the amount of fluoride release and surface roughness of only Amalgomer CR and Zirconomer. The effect could be related to the chemical compositions of materials.


Asunto(s)
Apatitas/efectos de la radiación , Radiación Ionizante , Bisfenol A Glicidil Metacrilato/efectos de la radiación , Resinas Compuestas/efectos de la radiación , Fluoruros/química , Cementos de Ionómero Vítreo/efectos de la radiación , Apatitas/química , Valores de Referencia , Espectrometría por Rayos X , Propiedades de Superficie/efectos de la radiación , Factores de Tiempo , Circonio/efectos de la radiación , Circonio/química , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Reproducibilidad de los Resultados , Análisis de Varianza , Bisfenol A Glicidil Metacrilato/química , Estadísticas no Paramétricas , Resinas Compuestas/química , Resistencia Flexional , Cementos de Ionómero Vítreo/química
5.
J. appl. oral sci ; J. appl. oral sci;28: e20190720, 2020. tab, graf
Artículo en Inglés | LILACS, BBO - Odontología | ID: biblio-1134776

RESUMEN

Abstract Objective This study evaluated the clinical effect of violet LED light on in-office bleaching used alone or combined with 37% carbamide peroxide (CP) or 35% hydrogen peroxide (HP). Methodology A total of 100 patients were divided into five groups (n=20): LED, LED/CP, CP, LED/HP and HP. Colorimetric evaluation was performed using a spectrophotometer (ΔE, ΔL, Δa, Δb) and a visual shade guide (ΔSGU). Calcium (Ca)/phosphorous (P) ratio was quantified in the enamel microbiopsies. Measurements were performed at baseline (T 0 ), after bleaching (T B ) and in the 14-day follow-up (T 14 ). At each bleaching session, a visual scale determined the absolute risk (AR) and intensity of tooth sensitivity (TS). Data were evaluated by one-way (ΔE, Δa, ΔL, Δb), two-way repeated measures ANOVA (Ca/P ratio), and Tukey post-hoc tests. ΔSGU and TS were evaluated by Kruskal-Wallis and Mann-Whitney, and AR by Chi-Squared tests (a=5%). Results LED produced the lowest ΔE (p<0.05), but LED/HP promoted greater ΔE, ΔSGU and Δb (T 14 ) than HP (p<0.05). No differences were observed in ΔE and ΔSGU for LED/CP and HP groups (p>0.05). ΔL and Δa were not influenced by LED activation. After bleaching, LED/CP exhibited greater Δb than CP (p>0.05), but no differences were found between these groups at T 14 (p>0.05). LED treatment promoted the lowest risk of TS (16%), while HP promoted the highest (94.4%) (p<0.05). No statistical differences of risk of TS were found for CP (44%), LED/CP (61%) and LED/HP (88%) groups (p>0.05). No differences were found in enamel Ca/P ratio among treatments, regardless of evaluation times. Conclusions Violet LED alone produced the lowest bleaching effect, but enhanced HP bleaching results. Patients treated with LED/CP reached the same efficacy of HP, with reduced risk and intensity of tooth sensitivity and none of the bleaching protocols adversely affected enamel mineral content.


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Fototerapia/métodos , Blanqueamiento de Dientes/métodos , Blanqueadores Dentales/administración & dosificación , Peróxido de Carbamida/administración & dosificación , Peróxido de Hidrógeno/administración & dosificación , Luz , Valores de Referencia , Espectrofotometría , Propiedades de Superficie/efectos de los fármacos , Propiedades de Superficie/efectos de la radiación , Factores de Riesgo , Análisis de Varianza , Resultado del Tratamiento , Colorimetría , Terapia Combinada , Estadísticas no Paramétricas , Esmalte Dental/efectos de los fármacos , Esmalte Dental/efectos de la radiación , Sensibilidad de la Dentina/inducido químicamente
6.
J. appl. oral sci ; J. appl. oral sci;28: e20190693, 2020. tab, graf
Artículo en Inglés | LILACS, BBO - Odontología | ID: biblio-1134791

RESUMEN

Abstract Debonding, staining and wear are usually the reasons for denture teeth replacement by new ones from same or different brands. Objective This study investigates the possible differences in color of denture teeth of the same or different brands under different illuminations, since their metameric behavior in color under specific illumination may become unacceptable. Methodology For the purpose of this study, 10 denture teeth (#11), shade A3, of 4 different brands were selected (Creopal/KlemaDental Pro, Executive/DeguDent, Cosmo HXL/DeguDent, Ivostar/Ivoclar-Vivadent). Teeth stabilized in white silicone mold and the CIELAB color coordinates of their labial surface under 3 different illumination lights (D65, F2, A) were recorded, using a portable colorimeter (FRU/WR-18, Wave Inc). ΔE*ab values of all possible pairs of teeth of the same brand (n=45) or pair combinations of different brands (n=100) under each illumination light, in a dry and wet state were calculated. Data were analyzed statistically using 3-way ANOVA, Friedman's and Wilcoxon's tests at a significance level of α=0.05. Results The results showed that brand type affected significantly L*, a* and b* coordinates (p<0.0001), illumination a* and b* coordinates (p<0.0001), but none of them was affected by the hydration state of teeth (p>0.05). Intra-brand color differences ranged between 0.21-0.78ΔΕ* units with significant differences among brands (p<0.0001), among illumination lights (p<0.0001) and between hydration states (p=0.0001). Inter-brand differences ranged between 2.29-6.29ΔΕ* units with significant differences among pairs of brands (p<0.0001), illumination lights (p<0.0001) and hydration states (p<0.0001). Conclusions Differences were found between and within brands under D65 illumination which increased under F2 or A illumination affected by brand type and hydration status. Executive was the most stable brand than the others under different illuminations or wet states and for this reason its difference from other brands is the lowest. In clinical practice, there should be no blending of teeth of different brands but if we must, we should select those that are more stable under different illuminations


Asunto(s)
Humanos , Iluminación , Dentaduras , Coloración de Prótesis , Valores de Referencia , Propiedades de Superficie/efectos de la radiación , Ensayo de Materiales , Análisis de Varianza , Colorimetría , Estadísticas no Paramétricas
7.
J Appl Oral Sci ; 27: e20180075, 2019 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-30624462

RESUMEN

Currently, there is no consensus in terms of defining the minimum radiant exposure values necessary for achieving adequate properties of composite resin. In addition, the long-term influence that radiant exposure has on the properties of composite resins is still questionable. OBJECTIVE: The objective of this study was to evaluate the effect of radiant exposure and UV accelerated aging on the physico-chemical and mechanical properties of micro-hybrid and nanofilled composite resins. MATERIAL AND METHODS: A nanofilled (Filtek Supreme; 3M ESPE) and a micro-hybrid composite resin (Filtek Z250; 3M ESPE) were investigated under different radiant exposures (3.75, 9, and 24 J/cm2) and UV accelerated aging protocols (0, 500, 1000, and 1500 aging hours). The degree of conversion (DC), flexural strength (FS), modulus (M), water sorption (WS), and solubility (WL) were evaluated. The results obtained were analyzed using two-way ANOVA and Tukey's test. Comparisons were performed using a significance level of α=0.05. RESULTS: The DC, FS, and M were found to be significantly influenced by both radiant exposure and accelerated aging time. The DC and EM increased with radiant exposure in the no-aging group (0-hour aging) for both micro-hybrid and nanofilled composites, whereas no correlation was found after accelerated aging protocols. WS and WL of micro-hybrid and nanofilled composite resins were scarcely affected by radiant exposure (p>0.05), whereas they were significantly reduced by accelerated aging (p<0.001). CONCLUSIONS: Although increasing radiant exposure affected the degree of conversion and mechanical properties of micro-hybrid and nanofilled composites, no influence on the hydrolytic degradation of the material was observed. In contrast, UV accelerated aging affected both the physico-chemical and mechanical properties of the composites.


Asunto(s)
Resinas Compuestas/química , Resinas Compuestas/efectos de la radiación , Rayos Ultravioleta , Análisis de Varianza , Luces de Curación Dental , Resistencia Flexional/efectos de la radiación , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Transición de Fase/efectos de la radiación , Procesos Fotoquímicos/efectos de la radiación , Polimerizacion/efectos de la radiación , Dosis de Radiación , Valores de Referencia , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie/efectos de la radiación , Factores de Tiempo , Agua/química
8.
J. appl. oral sci ; J. appl. oral sci;27: e20180126, 2019. tab, graf
Artículo en Inglés | LILACS, BBO - Odontología | ID: biblio-975877

RESUMEN

Abstract Objectives: The aim of this in vitro study was to evaluate the bonding strength of non-simplified dentin bonding systems (DBS) to dentin irradiated with a diode laser (970 nm) immediately and after 12 months of water storage following either primer or bond application. Material and methods: The experimental design included three different factors: DBS type [AdperTM Scotchbond Multipurpose (MP) and Clearfil™ SE Bond (CSE)], irradiation [without irradiation - control (C), irradiation after primer application (AP), and irradiation after bond application (AB)], and time [initial (I) and after 12 months of water storage (12 m)]. Sixty sound human third molars (n = 10) were obtained, and their flat occlusal dentin areas were prepared and standardized. Laser irradiation was performed in the contact mode perpendicular to the dental surface over an automatically selected scanning area at a pulse energy of 0.8 W, frequency of 10 Hz, and energy density of 66.67 J/cm2. After 7 days of treatment, the specimens were cut, and half of them were subjected to microtensile testing (500 N/0.05 mm/min), whereas the remaining sticks were examined after 12 months of water storage. The obtained data were analyzed by three-way analysis of variance (ANOVA) followed by a Tukey test (p<0.05). The observed fracture modes were investigated using a portable digital microscope with a magnification of 40x. Results: Among the utilized DBS, MP generally exhibited higher bond strengths, but did not always differ from CSE under similar conditions. The irradiation factor was statistically significant only for the MP/AB groups. After 12 months of storage, all groups demonstrated a significant reduction in the bond strength, whereas the results of fracture analysis showed a predominance of the adhesive type. Conclusions: The laser treatment of non-simplified DBS was not able to stabilize their bonding characteristics after 12 months.


Asunto(s)
Humanos , Recubrimiento Dental Adhesivo/métodos , Recubrimientos Dentinarios/efectos de la radiación , Cementos de Resina/efectos de la radiación , Dentina/efectos de la radiación , Láseres de Semiconductores , Valores de Referencia , Propiedades de Superficie/efectos de la radiación , Resistencia a la Tracción , Factores de Tiempo , Ensayo de Materiales , Agua/química , Reproducibilidad de los Resultados , Análisis de Varianza , Recubrimientos Dentinarios/química , Microscopía de Fuerza Atómica , Cementos de Resina/química , Dentina/efectos de los fármacos , Polimerizacion/efectos de la radiación
9.
J. appl. oral sci ; J. appl. oral sci;27: e20180075, 2019. graf
Artículo en Inglés | LILACS, BBO - Odontología | ID: biblio-975874

RESUMEN

Abstract Currently, there is no consensus in terms of defining the minimum radiant exposure values necessary for achieving adequate properties of composite resin. In addition, the long-term influence that radiant exposure has on the properties of composite resins is still questionable. Objective: The objective of this study was to evaluate the effect of radiant exposure and UV accelerated aging on the physico-chemical and mechanical properties of micro-hybrid and nanofilled composite resins. Material and Methods: A nanofilled (Filtek Supreme; 3M ESPE) and a micro-hybrid composite resin (Filtek Z250; 3M ESPE) were investigated under different radiant exposures (3.75, 9, and 24 J/cm2) and UV accelerated aging protocols (0, 500, 1000, and 1500 aging hours). The degree of conversion (DC), flexural strength (FS), modulus (M), water sorption (WS), and solubility (WL) were evaluated. The results obtained were analyzed using two-way ANOVA and Tukey's test. Comparisons were performed using a significance level of α=0.05. Results: The DC, FS, and M were found to be significantly influenced by both radiant exposure and accelerated aging time. The DC and EM increased with radiant exposure in the no-aging group (0-hour aging) for both micro-hybrid and nanofilled composites, whereas no correlation was found after accelerated aging protocols. WS and WL of micro-hybrid and nanofilled composite resins were scarcely affected by radiant exposure (p>0.05), whereas they were significantly reduced by accelerated aging (p<0.001). Conclusions: Although increasing radiant exposure affected the degree of conversion and mechanical properties of micro-hybrid and nanofilled composites, no influence on the hydrolytic degradation of the material was observed. In contrast, UV accelerated aging affected both the physico-chemical and mechanical properties of the composites.


Asunto(s)
Rayos Ultravioleta , Resinas Compuestas/efectos de la radiación , Resinas Compuestas/química , Dosis de Radiación , Valores de Referencia , Solubilidad , Propiedades de Superficie/efectos de la radiación , Factores de Tiempo , Ensayo de Materiales , Agua/química , Microscopía Electrónica de Rastreo , Análisis de Varianza , Espectroscopía Infrarroja por Transformada de Fourier , Transición de Fase/efectos de la radiación , Luces de Curación Dental , Procesos Fotoquímicos/efectos de la radiación , Polimerizacion/efectos de los fármacos , Resistencia Flexional/efectos de la radiación
10.
Braz Oral Res ; 32: e121, 2018 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-30517430

RESUMEN

The aim of this study was to evaluate the influence of radiation therapy on root canal sealer push-out bond strength (BS) to dentin and the sealer/dentin interface after different final irrigation solutions (NaOCl, EDTA, and chitosan). Sixty-four maxillary canines were distributed into two groups (n=30): non-irradiated and irradiated with 60 Gy. Canals were prepared with Reciproc-R50 and subdivided (n=10) for final irrigation (NaOCl, EDTA, chitosan) and filled. Three dentin slices were obtained from each root third. The first slice of each third was selected for BS evaluation, and the failure mode was determined by stereomicroscopy. SEM analysis of the sealer-dentin interface was performed in the remaining slices. Two-way ANOVA and Tukey's tests (α=0.05) were used. Lower BS (P<0.0001) was obtained after irradiation (2.07±0.79 MPa), regardless of the final irrigation solution used. The NaOCl group (P<0.001) had the lowest BS in the irradiated (1.68±0.72) and non-irradiated (2.39±0.89) groups, whereas the EDTA (irradiated: 2.14±0.77 and non-irradiated: 3.92±1.54) and chitosan (irradiated: 2.37±0.73 and non-irradiated: 3.51±1.47) groups demonstrated a higher BS (P<0.05). The highest values were observed in the coronal third (3.17±1.38) when compared to the middle (2.74±1.36) and apical ones (2.09±0.97)(P<0.0001). There were more cohesive failures and more gaps in irradiated specimens, regardless of the final solution. The present study showed that radiation was associated with a decrease in BS, regardless of the final solution used, whereas chitosan increased BS in teeth subjected to radiation therapy.


Asunto(s)
Recubrimiento Dental Adhesivo/métodos , Dentina/efectos de los fármacos , Dentina/efectos de la radiación , Resinas Epoxi/efectos de la radiación , Materiales de Obturación del Conducto Radicular/efectos de la radiación , Irrigantes del Conducto Radicular/efectos de la radiación , Análisis de Varianza , Quitosano/química , Fracaso de la Restauración Dental , Ácido Edético/química , Resinas Epoxi/química , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Reproducibilidad de los Resultados , Materiales de Obturación del Conducto Radicular/química , Irrigantes del Conducto Radicular/química , Hipoclorito de Sodio/química , Estadísticas no Paramétricas , Propiedades de Superficie/efectos de los fármacos , Propiedades de Superficie/efectos de la radiación , Raíz del Diente/efectos de los fármacos , Raíz del Diente/efectos de la radiación
11.
Braz Oral Res ; 32: e122, 2018 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-30569972

RESUMEN

The effects of tooth brushing could affect the long-term esthetic outcome of composite restorations. This study evaluated the effect of two different emission spectrum light-curing units on the surface roughness, roughness profile, topography and microhardness of bulk-fill composites after in vitro toothbrushing. Valo (multiple-peak) and Demi Ultra (single-peak) curing lights were each used for 10s to polymerize three bulk-fill resin composites: Filtek Bulk Fill Posterior Restorative (FBF), Tetric EvoCeram Bulk Fill (TET) and Surefil SDR Flow (SDR). After 30,000 reciprocal strokes in a toothbrushing machine, the roughness profile, surface roughness, surface morphology, and microhardness were examined. Representative SEM images were also obtained. When light-cured with the Demi Ultra, SDR showed the most loss in volume compared to the other composites and higher volume loss compared to when was light-cured with Valo. The highest surface roughness and roughness profile values were found in SDR after toothbrushing, for both light-curing units tested. FBF always had the greatest microhardness values. Light-curing TET with Valo resulted in higher microhardness compared to when using the Demi Ultra. Confocal and SEM images show that toothbrushing resulted in smoother surfaces for FBF and TET. All composites exhibited surface volume loss after toothbrushing. The loss in volume of SDR depended on the light-curing unit used. Toothbrushing can alter the surface roughness and superficial aspect of some bulk-fill composites. The choice of light-curing unit did not affect the roughness profile, but, depending on the composite, it affected the microhardness.


Asunto(s)
Resinas Compuestas/efectos de la radiación , Luces de Curación Dental , Cepillado Dental/efectos adversos , Análisis de Varianza , Resinas Compuestas/química , Dureza/efectos de los fármacos , Dureza/efectos de la radiación , Curación por Luz de Adhesivos Dentales/métodos , Ensayo de Materiales , Microscopía Confocal , Microscopía Electrónica de Rastreo , Polimerizacion , Reproducibilidad de los Resultados , Propiedades de Superficie/efectos de los fármacos , Propiedades de Superficie/efectos de la radiación , Factores de Tiempo
12.
J Appl Oral Sci ; 27: e20180126, 2018 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-30540073

RESUMEN

OBJECTIVES: The aim of this in vitro study was to evaluate the bonding strength of non-simplified dentin bonding systems (DBS) to dentin irradiated with a diode laser (970 nm) immediately and after 12 months of water storage following either primer or bond application. MATERIAL AND METHODS: The experimental design included three different factors: DBS type [AdperTM Scotchbond Multipurpose (MP) and Clearfil™ SE Bond (CSE)], irradiation [without irradiation - control (C), irradiation after primer application (AP), and irradiation after bond application (AB)], and time [initial (I) and after 12 months of water storage (12 m)]. Sixty sound human third molars (n = 10) were obtained, and their flat occlusal dentin areas were prepared and standardized. Laser irradiation was performed in the contact mode perpendicular to the dental surface over an automatically selected scanning area at a pulse energy of 0.8 W, frequency of 10 Hz, and energy density of 66.67 J/cm2. After 7 days of treatment, the specimens were cut, and half of them were subjected to microtensile testing (500 N/0.05 mm/min), whereas the remaining sticks were examined after 12 months of water storage. The obtained data were analyzed by three-way analysis of variance (ANOVA) followed by a Tukey test (p<0.05). The observed fracture modes were investigated using a portable digital microscope with a magnification of 40x. RESULTS: Among the utilized DBS, MP generally exhibited higher bond strengths, but did not always differ from CSE under similar conditions. The irradiation factor was statistically significant only for the MP/AB groups. After 12 months of storage, all groups demonstrated a significant reduction in the bond strength, whereas the results of fracture analysis showed a predominance of the adhesive type. CONCLUSIONS: The laser treatment of non-simplified DBS was not able to stabilize their bonding characteristics after 12 months.


Asunto(s)
Recubrimiento Dental Adhesivo/métodos , Recubrimientos Dentinarios/efectos de la radiación , Dentina/efectos de la radiación , Láseres de Semiconductores , Cementos de Resina/efectos de la radiación , Análisis de Varianza , Dentina/efectos de los fármacos , Recubrimientos Dentinarios/química , Humanos , Ensayo de Materiales , Microscopía de Fuerza Atómica , Polimerizacion/efectos de la radiación , Valores de Referencia , Reproducibilidad de los Resultados , Cementos de Resina/química , Propiedades de Superficie/efectos de la radiación , Resistencia a la Tracción , Factores de Tiempo , Agua/química
13.
Braz Oral Res ; 32: e47, 2018 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-30281682

RESUMEN

The objective of this study was to assess the effect of a UV light-based auxiliary illumination on adhesive remnant (AR) removal after orthodontic debonding. Sixty human molars were divided according to the adhesive used for bonding: O-opaque; LF-low fluorescence; and HF-high fluorescence. After debonding, the teeth were subdivided according to the AR removal method: No UV light or With UV light. After AR removal, the teeth were polished. Direct visual analysis, scanning electron microscopy (SEM) and time quantification for AR removal analyses were performed (Fisher-Freeman-Halton, Fisher's exact, chi-square trend, ANOVA, and independent t-tests; α = 5%). Concerning the adhesives, there was no significant difference among direct visual, SEM and time analyses for AR removal (p ≥ 0.05). Regarding AR removal methods, a similarity among the subgroups was verified for direct visual and SEM analyses (p≥0.05). However, a significant trend was verified for the with UV light method to produce greater marks, and the no UV light method, to produce a greater rate of samples with AR before polishing (p = 0.015). AR removal with light was significantly quicker in comparison with the no UV light method (p < 0.0001). The use of UV light may aid orthodontists in removing AR more thoroughly and in less time. However, they should receive special training to apply this technology, and should never dismiss the final polishing procedure.


Asunto(s)
Cementos Dentales/efectos de la radiación , Desconsolidación Dental/métodos , Esmalte Dental/efectos de la radiación , Aparatos Ortodóncicos , Rayos Ultravioleta , Análisis de Varianza , Cementos Dentales/química , Pulido Dental/métodos , Humanos , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Valores de Referencia , Reproducibilidad de los Resultados , Propiedades de Superficie/efectos de la radiación , Factores de Tiempo
14.
Microsc Res Tech ; 81(9): 973-979, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30295342

RESUMEN

The aim of this study was to evaluate the chemical and morphological effects of different lasers as a final surface treatment for endodontic therapy through energy dispersive X-ray spectroscopy (EDS) and scanning electron microscopy (SEM) respectively. Twenty-five maxillary canines were selected and instrumented with K3 system. Roots were randomly distributed into five groups (n = 5) according to the surface treatment: GI (distilled water), GII (NaOCl + EDTA), GIII (NaOCl + EDTA + 980 nm diode laser), GIV (NaOCl + EDTA+ 1,064 nm Nd:YAG laser), and GV (NaOCl + EDTA+ 2,780 nm Er, Cr:YSGG laser). Lasers were applied for 20 s and samples were bisected, exposing the treated surface and then subjected to elements quantification by EDS and morphological evaluation by scanning electron microscope (SEM). EDS data were submitted to ANOVA-two way, and SEM scores were submitted to two-way Kruskal-Wallis and Dunn's tests. The EDS analysis showed no difference for the chemical elements and Ca/P ratio between groups (p > .05). Statistical analysis showed more intense results for GV and less intense results for GI (p < .05). The GIII showed an amorphous organic matrix surface, while GV provided greater removal of intertubular dentin forming craters, and GIV promoted dentin fusion. The EDS method used in this study was not able to verify any chemical changes in root canal dentin; Nd:YAG, Er, Cr:YSGG, and 980 nm diode laser were capable of modifying the dentin morphology, correlating characteristics features for each one, which are essential clinical knowledge to establish the correct indication for each case. RESEARCH HIGHLIGHTS: EDS was not able to verify any chemical changes in root canal dentin after 980 nm diode, Nd:YAG and Er;Cr:YSGG laser treatments Nd:YAG, Er, Cr:YSGG, and 980 nm diode laser modified dentin morphology, correlating characteristics features for each one.


Asunto(s)
Diente Canino/efectos de la radiación , Dentina/efectos de la radiación , Terapia por Luz de Baja Intensidad , Raíz del Diente/efectos de la radiación , Diente no Vital , Diente Canino/anatomía & histología , Diente Canino/química , Dentina/anatomía & histología , Dentina/química , Humanos , Microscopía Electrónica de Rastreo , Espectrometría por Rayos X , Propiedades de Superficie/efectos de la radiación , Raíz del Diente/anatomía & histología , Raíz del Diente/química
15.
J Appl Oral Sci ; 26: e20170029, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29742259

RESUMEN

Literature has reported positive results regarding the use of lasers in the control of erosive lesions; however, evaluating whether they are effective in the control of the progression of erosive/abrasive lesions is important. Objectives This study aimed to evaluate the effect of the Er:YAG laser irradiation in controlling the progression of erosion associated with abrasive lesions in enamel. Material and methods Bovine incisors were sectioned, flattened and polished. Forty-eight enamel slabs were subjected to treatment in an intraoral phase. Twelve volunteers used an intraoral appliance containing one slab that was irradiated with an Er:YAG laser (5.2 J/cm2, 85 mJ, 2 Hz) and another non-irradiated slab on each side of the appliance, during one phase of 5 d, under a split-mouth design. Devices were subjected to erosive challenges (1% citric acid, 5 min, 3 times a day) and abrasive challenges one h after (brushing force of 1.5 N for 15 s) randomly and independently on each side of the device. Measurements of enamel loss were performed via 3D optical profilometry (µm). We analyzed data using the Kruskal-Wallis and Mann-Whitney tests and morphological characteristics via scanning electron microscopy. Results Following erosive and abrasive challenges, the group that was irradiated with the Er:YAG laser presented less loss of structure than the non-irradiated group. The group that underwent erosion and irradiation did not exhibit a significant difference from the non-irradiated group. Conclusion Irradiation with the Er:YAG laser did not control the loss of structure of enamel subjected to erosion but did control abrasion after erosion.


Asunto(s)
Esmalte Dental/efectos de la radiación , Láseres de Estado Sólido/uso terapéutico , Abrasión de los Dientes/prevención & control , Erosión de los Dientes/prevención & control , Animales , Bovinos , Ácido Cítrico/química , Esmalte Dental/efectos de los fármacos , Progresión de la Enfermedad , Pruebas de Dureza , Imagenología Tridimensional , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Reproducibilidad de los Resultados , Estadísticas no Paramétricas , Propiedades de Superficie/efectos de la radiación
16.
An Acad Bras Cienc ; 90(1): 195-204, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29641759

RESUMEN

Demand for medical implants is rising day by day as the world becomes the place for more diseased and older people. Accordingly, in this research, metallocene polyethylene (mPE), a commonly used polymer was treated with UV rays for improving its biocompatibility. Scanning electron microscopy (SEM) images confirmed the formation of crests and troughs, which depicts the improvement of surface roughness of mPE substrates caused by UV etching. Accordingly, the contact angle measurements revealed that the wettability of mPE-2.5 J/cm2 (68.09º) and mPE-5 J/cm2 (57.93º) samples were found to be increased compared to untreated mPE (86.84º) indicating better hydrophilicity. Further, the UV treated surface exhibited enhanced blood compatibility as determined in APTT (untreated mPE- 55.3 ± 2.5 s, mPE-2.5 J/cm2 - 76.7 ± 4.1 s and mPE-5 J/cm2 - 112.3 ± 2 s) and PT (untreated mPE - 24.7 ± 1.5 s, mPE- 2.5 J/cm2 - 34.3 ± 1.1 s and mPE-5 J/cm2 - 43 ± 2 s) assay. Moreover, the treated mPE-2.5 J/cm2 (4.88%) and mPE-5 J/cm2 (1.79%) showed decreased hemolytic percentage compared to untreated mPE (15.40%) indicating better safety to red blood cells. Interestingly, the changes in physicochemical properties of mPE are directly proportional to the dosage of the UV rays. UV modified mPE surfaces were found to be more compatible as identified through MTT assay, photomicrograph and SEM images of the seeded 3T3 cell population. Hence UV-modified surface of mPE may be successfully exploited for medical implants.


Asunto(s)
Ensayo de Materiales , Metalocenos/efectos de la radiación , Rayos Ultravioleta , Células 3T3 , Animales , Bovinos , Hemólisis , Histocompatibilidad , Interacciones Hidrofóbicas e Hidrofílicas , Metalocenos/química , Ratones , Microscopía Electrónica de Rastreo , Conejos , Propiedades de Superficie/efectos de la radiación
17.
An. acad. bras. ciênc ; 90(1): 195-204, Mar. 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-886907

RESUMEN

ABSTRACT Demand for medical implants is rising day by day as the world becomes the place for more diseased and older people. Accordingly, in this research, metallocene polyethylene (mPE), a commonly used polymer was treated with UV rays for improving its biocompatibility. Scanning electron microscopy (SEM) images confirmed the formation of crests and troughs, which depicts the improvement of surface roughness of mPE substrates caused by UV etching. Accordingly, the contact angle measurements revealed that the wettability of mPE-2.5 J/cm2 (68.09º) and mPE-5 J/cm2 (57.93º) samples were found to be increased compared to untreated mPE (86.84º) indicating better hydrophilicity. Further, the UV treated surface exhibited enhanced blood compatibility as determined in APTT (untreated mPE- 55.3 ± 2.5 s, mPE-2.5 J/cm2 - 76.7 ± 4.1 s and mPE-5 J/cm2 - 112.3 ± 2 s) and PT (untreated mPE - 24.7 ± 1.5 s, mPE- 2.5 J/cm2 - 34.3 ± 1.1 s and mPE-5 J/cm2 - 43 ± 2 s) assay. Moreover, the treated mPE-2.5 J/cm2 (4.88%) and mPE-5 J/cm2 (1.79%) showed decreased hemolytic percentage compared to untreated mPE (15.40%) indicating better safety to red blood cells. Interestingly, the changes in physicochemical properties of mPE are directly proportional to the dosage of the UV rays. UV modified mPE surfaces were found to be more compatible as identified through MTT assay, photomicrograph and SEM images of the seeded 3T3 cell population. Hence UV-modified surface of mPE may be successfully exploited for medical implants.


Asunto(s)
Animales , Conejos , Ratas , Rayos Ultravioleta , Ensayo de Materiales , Metalocenos/efectos de la radiación , Propiedades de Superficie/efectos de la radiación , Bovinos , Microscopía Electrónica de Rastreo , Células 3T3 , Interacciones Hidrofóbicas e Hidrofílicas , Metalocenos/química , Hemólisis , Histocompatibilidad
18.
J Appl Oral Sci ; 26: e20160662, 2018 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-29364336

RESUMEN

The main goal of this study was to compare the polymerization degree of bulk-fill giomer resin cured with three different light-curing units (LCUs): a polywave third-generation (Valo); a monowave (DemiUltra: DU); and a second-generation LED (Optima 10: Opt) LCUs by using structural and mechanical properties. Giomer samples of 2 and 4 mm cured with three LCUs were employed in vitro analysis. The degree of curing (DC%) was determined with Fourier-Transform Infrared Spectroscopy (FTIR). Microstructural features were observed with scanning electron microscopy (SEM). Flexural strength (FS), compression strength (CS), elastic modulus and fracturing strain were determined for mechanical properties. Surface microhardness (SMH) values were also measured. Oneway ANOVA, two-way analysis of variance and Tukey multiple comparison tests were used for statistically analyzing the FS and SMH. DC% values were 58.2, 47.6, and 39.7 for the 2 mm samples cured with DU, Opt., and Valo LCUs, respectively. DC% values of the 4 mm samples were 50.4, 44.6, and 38.2 for DU, Opt, and Valo, respectively. SMH values were Valo, Opt

Asunto(s)
Bisfenol A Glicidil Metacrilato/química , Bisfenol A Glicidil Metacrilato/efectos de la radiación , Resinas Compuestas/química , Resinas Compuestas/efectos de la radiación , Curación por Luz de Adhesivos Dentales/métodos , Polimerizacion/efectos de la radiación , Análisis de Varianza , Fuerza Compresiva , Módulo de Elasticidad , Pruebas de Dureza , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Valores de Referencia , Reproducibilidad de los Resultados , Espectroscopía Infrarroja por Transformada de Fourier , Estadísticas no Paramétricas , Propiedades de Superficie/efectos de la radiación , Factores de Tiempo
19.
Braz. oral res. (Online) ; 32: e121, 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-974461

RESUMEN

Abstract The aim of this study was to evaluate the influence of radiation therapy on root canal sealer push-out bond strength (BS) to dentin and the sealer/dentin interface after different final irrigation solutions (NaOCl, EDTA, and chitosan). Sixty-four maxillary canines were distributed into two groups (n=30): non-irradiated and irradiated with 60 Gy. Canals were prepared with Reciproc-R50 and subdivided (n=10) for final irrigation (NaOCl, EDTA, chitosan) and filled. Three dentin slices were obtained from each root third. The first slice of each third was selected for BS evaluation, and the failure mode was determined by stereomicroscopy. SEM analysis of the sealer-dentin interface was performed in the remaining slices. Two-way ANOVA and Tukey's tests (α=0.05) were used. Lower BS (P<0.0001) was obtained after irradiation (2.07±0.79 MPa), regardless of the final irrigation solution used. The NaOCl group (P<0.001) had the lowest BS in the irradiated (1.68±0.72) and non-irradiated (2.39±0.89) groups, whereas the EDTA (irradiated: 2.14±0.77 and non-irradiated: 3.92±1.54) and chitosan (irradiated: 2.37±0.73 and non-irradiated: 3.51±1.47) groups demonstrated a higher BS (P<0.05). The highest values were observed in the coronal third (3.17±1.38) when compared to the middle (2.74±1.36) and apical ones (2.09±0.97)(P<0.0001). There were more cohesive failures and more gaps in irradiated specimens, regardless of the final solution. The present study showed that radiation was associated with a decrease in BS, regardless of the final solution used, whereas chitosan increased BS in teeth subjected to radiation therapy.


Asunto(s)
Humanos , Materiales de Obturación del Conducto Radicular/efectos de la radiación , Irrigantes del Conducto Radicular/efectos de la radiación , Recubrimiento Dental Adhesivo/métodos , Dentina/efectos de los fármacos , Dentina/efectos de la radiación , Resinas Epoxi/efectos de la radiación , Materiales de Obturación del Conducto Radicular/química , Irrigantes del Conducto Radicular/química , Hipoclorito de Sodio/química , Propiedades de Superficie/efectos de los fármacos , Propiedades de Superficie/efectos de la radiación , Raíz del Diente/efectos de los fármacos , Raíz del Diente/efectos de la radiación , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Reproducibilidad de los Resultados , Análisis de Varianza , Ácido Edético/química , Estadísticas no Paramétricas , Fracaso de la Restauración Dental , Quitosano/química , Resinas Epoxi/química , Neoplasias de Cabeza y Cuello/radioterapia
20.
Braz. oral res. (Online) ; 32: e122, 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-974460

RESUMEN

Abstract: The effects of tooth brushing could affect the long-term esthetic outcome of composite restorations. This study evaluated the effect of two different emission spectrum light-curing units on the surface roughness, roughness profile, topography and microhardness of bulk-fill composites after in vitro toothbrushing. Valo (multiple-peak) and Demi Ultra (single-peak) curing lights were each used for 10s to polymerize three bulk-fill resin composites: Filtek Bulk Fill Posterior Restorative (FBF), Tetric EvoCeram Bulk Fill (TET) and Surefil SDR Flow (SDR). After 30,000 reciprocal strokes in a toothbrushing machine, the roughness profile, surface roughness, surface morphology, and microhardness were examined. Representative SEM images were also obtained. When light-cured with the Demi Ultra, SDR showed the most loss in volume compared to the other composites and higher volume loss compared to when was light-cured with Valo. The highest surface roughness and roughness profile values were found in SDR after toothbrushing, for both light-curing units tested. FBF always had the greatest microhardness values. Light-curing TET with Valo resulted in higher microhardness compared to when using the Demi Ultra. Confocal and SEM images show that toothbrushing resulted in smoother surfaces for FBF and TET. All composites exhibited surface volume loss after toothbrushing. The loss in volume of SDR depended on the light-curing unit used. Toothbrushing can alter the surface roughness and superficial aspect of some bulk-fill composites. The choice of light-curing unit did not affect the roughness profile, but, depending on the composite, it affected the microhardness.


Asunto(s)
Cepillado Dental/efectos adversos , Resinas Compuestas/efectos de la radiación , Luces de Curación Dental , Propiedades de Superficie/efectos de los fármacos , Propiedades de Superficie/efectos de la radiación , Factores de Tiempo , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Reproducibilidad de los Resultados , Análisis de Varianza , Microscopía Confocal , Resinas Compuestas/química , Curación por Luz de Adhesivos Dentales/métodos , Polimerizacion , Dureza/efectos de los fármacos , Dureza/efectos de la radiación
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