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1.
J Appl Oral Sci ; 28: e20190499, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32348441

RESUMEN

Enzymatic degradation of the hybrid layer can be accelerated by the activation of dentin metalloproteinases (MMP) during the bonding procedure. MMP inhibitors may be used to contain this process. Objective To evaluate the degree of conversion (DC%), dentin bond strength (µTBS) (immediate and after 1 year of storage in water), and nanoleakage of an experimental (EXP) and a commercial (SB) adhesive system, containing different concentrations of the MMP inhibitor GM1489: 0, 1 µM, 5 µM and 10 µM. Methodology DC% was evaluated by FT-IR spectroscopy. Dentin bond strength was evaluated by µTBS test. Half of beams were submitted to the µTBS test after 24 h and the other half, after storage for 1 year. From each tooth and storage time, 2 beams were reserved for nanoleakage testing. Data were analyzed using ANOVA and Tukey's test to compare means (α=0.05). Results All adhesive systems maintained the µTBS after 1 year of storage. Groups with higher concentrations of inhibitor (5 µM and 10 µM) showed higher µTBS values than groups without inhibitor or with 1 µM. The nanoleakage values of all groups showed no increase after 1 year of storage and values were similar for SB and EXP groups, in both storage periods. The inhibitor did not affect the DC% of the EXP groups, but the SB5 and SB10 groups showed higher DC% values than those of SB0 and SB1. Conclusions The incorporation of GM1489 in the adhesive systems had no detrimental effect on DC%. The concentrations of 5 µM GM1489 for SB and 5 µM or 10 µM for EXP provided higher µTBS than groups without GM1489, in the evaluation after 1 year of storage; whereas the concentration of inhibitor did not affect adhesive systems nanoleakage.


Asunto(s)
Cementos Dentales/química , Dentina/química , Inhibidores de la Metaloproteinasa de la Matriz/química , Metacrilatos/química , Polietilenglicoles/química , Ácidos Polimetacrílicos/química , Análisis de Varianza , Recubrimiento Dental Adhesivo/métodos , Grabado Dental/métodos , Filtración Dental , Dentina/efectos de los fármacos , Humanos , Ensayo de Materiales , Valores de Referencia , Reproducibilidad de los Resultados , Espectroscopía Infrarroja por Transformada de Fourier , Estadísticas no Paramétricas , Propiedades de Superficie , Resistencia a la Tracción , Factores de Tiempo
2.
PLoS One ; 15(3): e0229595, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32119700

RESUMEN

OBJECTIVES: To assess and compare the enamel surface quality after interproximal enamel reduction (IPR) was performed with different systems and to study the relation between acid penetration depth and enamel surface quality as well as the importance of remineralization. METHODS: Sixty-five extracted teeth were randomly allocated to five experimental groups: untreated control, manual with New Metal Strips, mechanical with oscillating segment (OS) discs, Safe-Tipped Bur Kit, and the Ortho-Strip, followed by 30 s of polishing with the Softflex system and the Compo-system after treating the tooth with OS discs. Mesial surfaces were demineralized for 24 h and distal surfaces were subjected to interchanging demineralization and remineralization cycles of 24 h each for 18 days. The analysis was carried out by profilometry, scanning electron microscopy, and polarization microscopy. RESULTS: After IPR and polishing, enamel roughness was reduced for all systems tested except for the Essix Safe-Tipped Bur Kit. Subsequent demineralization increased enamel roughness in all groups except controls beyond the original level prior to IPR except for IPR with New Metal Strips or Ortho-Strips and subsequent polishing. Cyclic demineralization and remineralization for 18 days yielded a reduction in acid penetration depth and an increase in surface smoothness, which correlated with each other only for controls and treatment with New Metal Strips or Ortho-Strips. CONCLUSIONS: Manual IPR, using New Metal Strips and, even more, the oscillating IPR system Ortho-Strips, yielded smoother interproximal enamel surfaces and less acid penetration depth than the IPR systems with OS discs and the Safe-Tipped Bur Kit after polishing and 18 days of cyclic demineralization and remineralization. Irrespective of the IPR procedure, proper remineralization of IPR-treated surfaces is advisable to reduce caries susceptibility.


Asunto(s)
Esmalte Dental/fisiología , Grabado Dental/métodos , Humanos , Microscopía Electrónica de Rastreo , Microscopía de Polarización , Propiedades de Superficie , Diente/fisiología
3.
Niger J Clin Pract ; 23(2): 165-171, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32031090

RESUMEN

Aims: The aim of this study is to evaluate the effect of the diode laser used for dentin sensitivity on the clinical success of non-carious cervical lesion (NCCL) restorations restored with different adhesive systems. Methods: 20 NCCLs were restorated with Universal Single Bond (Self Etch) (3M, USA) and Grandio (Voco, Germany), 20 NCCLs were restorated with Universal Single Bond (Total Etch) and Grandio. After diode laser application, 20 NCCLs were restorated with Universal Single Bond and Grandio, 20 NCCLs were restorated with Universal Single Bond (Total Etch) and Grandio. The restorations were clinical evaluated by two examiners at baseline, for 6 and 18 months using modified United States Public Health Service (USPHS) Criteria. Chi-square test was used for statistical analyse. Results: The lowest rates of retention was found in the Group 1. There was no statistically significant difference among the groups in marginal discoloration, marginal integrity, sensitivity (P > 0.05). Conclusion: Diode laser application prior to the restoration of teeth with NCCL don't reduce the retention rate of restorations, may reduce hypersensitivity and may affect the success of restoration. However, further laboratory and clinical studies are required.


Asunto(s)
Adhesivos/farmacología , Resinas Compuestas , Grabado Dental , Restauración Dental Permanente/métodos , Láseres de Semiconductores/uso terapéutico , Cuello del Diente , Adulto , Bisfenol A Glicidil Metacrilato , Adaptación Marginal Dental , Sensibilidad de la Dentina , Recubrimientos Dentinarios , Femenino , Estudios de Seguimiento , Humanos , Láseres de Semiconductores/efectos adversos , Masculino , Persona de Mediana Edad
4.
Niger J Clin Pract ; 23(1): 110-115, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31929216

RESUMEN

Objective: The aim of this study was to compare to effect of phototherapy and surface flattening after immediately bleaching on the shear bond strength to bleached enamel. Methods: Ninety-six human upper incisors were divided into 4 groups (n = 24). Group NB: no bleached, group P: phototherapy with YSGG laser, group F: 0.5 mm surface flattening, group PF: 0.5 mm surface flattening and phototherapy with Er;Cr:YSGG laser. Then, each group was assigned to 2 subgroups according to adhesive mode (n = 12) as; subgroup S (self-etching mode), subgroup T (total-etching mode) which are universal adhesives. All surface conditionings and restorations were performed with composite resin materials immediately after bleaching. Shear bond strength test was performed by using universal testing machine. The surfaces were also evaluated with SEM. The data were statistically analyzed with one-way ANOVA post-hoc Tukey tests. Results: The lowest SBS values were achieved in FS (13.72 ± 2.29) while the highest ones in PT (28.01 ± 6.81). However, the differences were not significant (P > 0.05). All surface conditioning methods provided SBS values similar to the control (P > 0.05). All subgroups of self-etching mode were significantly lower than their total-etching counterparts (P < 0.05). Conclusions: The present study showed that surface removal and phototherapy have a potential clinical application for eliminate to undesirable effect of bleaching treatment. Surface conditioning with either flattening and/or phototherapy may provide clinicians to restore bleached teeth at the same visit with bleaching and reduce chair-time.


Asunto(s)
Adhesivos/farmacología , Recubrimiento Dental Adhesivo/métodos , Esmalte Dental/efectos de los fármacos , Grabado Dental/métodos , Láseres de Estado Sólido/uso terapéutico , Fototerapia , Resistencia al Corte , Blanqueamiento de Dientes , Grabado Ácido Dental/métodos , Resinas Compuestas/química , Materiales Dentales/química , Humanos , Ensayo de Materiales , Blanqueamiento de Dientes/métodos
5.
J Prosthodont ; 29(2): 136-141, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29131447

RESUMEN

PURPOSE: To investigate the effect of different surface treatments on the surface roughness (Ra), wettability, and shear bond strength of polyetheretherketone (PEEK) to composite resin. MATERIALS AND METHODS: One hundred ninety eight PEEK specimens were divided into six groups (n = 33). Specimen surfaces were treated with the following surface treatment modalities: silicoating (CoJet), acetone treatment, acid etching (H2 SO4 ), airborne particle abrasion (Al2 O3 ), laser irradiation (Yb:PL laser), and the nontreated surface serving as the control. Surface roughness was measured with an profilometer (n = 11) and a goniometer was used to measure the surface wettability through contact angle (θ)(n = 11). PEEK surfaces were veneered with a composite resin (n = 11). The specimens were then thermocycled for 10,000 cycles at 5 to 55°C. Shear bond strengths between the PEEK and composite resin were measured with an universal test machine. One-way ANOVA was used to analyze the data. Tukey's post-hoc test was used to determine significant differences between groups (α = 0.05). RESULTS: Surface roughness and wettability of PEEK surfaces along with shear bond strength of PEEK to composite resin were influenced by the surface treatments. (p < 0.01) Highest mean Ra values were obtained for PEEK surfaces treated by laser irradiation (2.85 ± 0.2 µm) followed by airborne particle abrasion (2.26 ± 0.33 µm), whereas other surface treatment modalities provided similar Ra values, with the acid-etched PEEK surfaces having the lowest mean Ra values (0.35 ± 0.14 µm). Silicoating provided the most wettable PEEK surfaces (48.04 ± 6.28º), followed by either acetone treatment (70.19 ± 4.49º) or acid treatment (76.07 ± 6.61º). Decreased wettability was observed for airborne particle abraded (84.83 ± 4.56º) and laser-treated PEEK surfaces (103.06 ± 4.88º). The highest mean shear bond strength values were observed for acid-etched PEEK surfaces (15.82 ± 4.23 MPa) followed by laser irradiated (11.46 ± 1.97 MPa), airborne particle abraded (10.81 ± 3.06 MPa), and silicoated PEEK surfaces (8.07 ± 2.54 MPa). Acetone-treated (5.98 ± 1.54 MPa) and untreated PEEK surfaces (5.09 ± 2.14 MPa) provided the lowest mean shear bond strengths. CONCLUSIONS: The highest mean shear bond strengths were observed for acid-etched PEEK surfaces, followed by laser-irradiated, airborne particle abraded, and silicoated PEEK surfaces providing similar mean shear bond strengths. Since shear bond strengths higher than 10 MPa are considered acceptable, acid etching, laser irradiation, and airborne particle abrasion of PEEK surfaces may be considered viable surface treatment modalities for the PEEK material tested.


Asunto(s)
Recubrimiento Dental Adhesivo , Grabado Dental , Resinas Compuestas , Análisis del Estrés Dental , Cetonas , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Polietilenglicoles , Cementos de Resina , Resistencia al Corte , Propiedades de Superficie
6.
Niger J Clin Pract ; 22(12): 1758-1764, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31793485

RESUMEN

Aim: The aim of this in vitro study was to compare the effects of the application of three different cavity disinfecting agents to dentin on the micro-shear bond strength (µ-SBS) of one self-etch and two universal adhesive systems. Materials and Methods: In total, 120 caries-free human permanent molar teeth were used in this study. Mid-coronal dentin surfaces were revealed by cutting occlusal enamel and a standard smear layer was obtained by using 600-800-1200 grid silicon carbide abrasive papers. Specimens were randomly assigned to four groups according to the disinfectant used: Group 1: Control (no disinfectant); Group 2: 2% chlorhexidine based (Consepsis); Group 3: 10 ppm ozonated water (TeknO3zone); Group 4: 5% boric acid (Handmade). Each group was divided into three subgroups according to the type of adhesive (Clearfil SE Bond, OptiBond XTR, and Tokuyama Universal). Specimens were bonded using either Clearfil SE Bond, OptiBond XTR or Tokuyama Universal, which were employed according to the manufacturer's instructions. Resin composite microcylinders were bonded using Tygon® tubes for µ-SBS testing. After specimens were stored for 24 h, at 37°C in distilled water, µ-SBS test was measured with a universal test machine (LF Plus, Lloyd, Instrument). µ-SBS results were analyzed by one-way analysis of variance (ANOVA) and Tukey's tests. Results: When the mean microshear bond strength values of the control group were compared, the difference between the subgroups was not significant (P < 0.05). When the mean microshear bond strength values of the chx, ozonated water, and boric acid were compared, the difference between Clearfil SE Bond and Tokuyama Universal was significant (P < 0.05) and the difference between the other groups was not significant (P > 0.05). Conclusion: Ozonated water and boric acid may be as an alternative to other materials used as cavity disinfectants.


Asunto(s)
Ácidos Bóricos , Recubrimiento Dental Adhesivo/métodos , Cementos Dentales , Desinfectantes Dentales/farmacología , Recubrimientos Dentinarios , Dentina/efectos de los fármacos , Agua , Clorhexidina , Resinas Compuestas/química , Esmalte Dental , Grabado Dental/métodos , Humanos , Cementos de Resina/uso terapéutico , Capa de Barro Dentinario
7.
Niger J Clin Pract ; 22(10): 1441-1447, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31607737

RESUMEN

Background: There was no enough data about the appropriate surface cleaning of core composite material after temporary cementation. Aim: To evaluate the effects of surface cleaning techniques on initial shear bond strength (SBS) between core composite material and resin nanoceramic crown materials after temporary cementation. Material and Methods: Cubic specimens were prepared from prosthetic materials, including Lava Ultimate. Cylinder-shaped composites were cemented to glass slides with eugenol-free temporary cement, resulting in a total of 44 cylinders (n = 11). The surfaces of composite cylinders were then cleaned with an Er, Cr:YSGG laser, 37% orthophosphoric acid, yellow tape diamond bur, or dental explorer. Cleaned cylinders were bonded to cubic specimens with resin cement. Initial SBS tests were performed with a universal testing machine at 0.5 mm/min crosshead speed. One-way ANOVA and post hoc Tukey tests were used to analyze the obtained data (P =0.05). Results: Initial SBS values were significantly affected by the different surface cleaning methods (P <.05). The highest SBS value was obtained with the laser group (SBS = 17.14), while the lowest was obtained with dental explorer group (SBS = 5.95). There was no significant difference between the diamond bur group and the laser group (P =0.982). Conclusions: Laser irradiation or yellow tape diamond bur cleaning of the core composite surface could be recommended to strengthen bond strength between the resin luting cement and the core composite. Before adhesive or conventional cementation of prosthetic restoration, the core composite surface should be cleaned.


Asunto(s)
Recubrimiento Dental Adhesivo/métodos , Cementos Dentales/química , Grabado Dental/métodos , Recubrimientos Dentinarios/química , Vidrio/química , Láseres de Estado Sólido/uso terapéutico , Cementos de Resina/química , Cementación , Resinas Compuestas/química , Cementos de Ionómero Vitreo , Humanos , Ensayo de Materiales , Resistencia al Corte , Propiedades de Superficie
8.
J Adhes Dent ; 21(5): 401-411, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31624805

RESUMEN

PURPOSE: To investigate the effects of grit blasting, acidic or alkaline/heat treatments, and metal primer application on the shear bond strength (SBS) of resin cement to machined commercially pure titanium (CP-Ti). MATERIALS AND METHODS: Titanium plates were machined and received one of the following treatments: grit-blasting (GB), or grit-blasting followed by either acidic treatment (GB/AC) or alkaline/heat treatment (GB/AH). The specimens were randomly divided into 4 groups and treated with Rely X Ceramic Primer (RCP), Z Prime Plus (ZPP), and Alloy Primer (ALP), or without primer as the control. The pairs of titanium plates were cemented together with the Rely X Unicem cement. SBS was measured before and after thermocycling between 5°C and 55°C for 5000 cycles. RESULTS: SEM observation showed that honeycomb-shaped pores formed on the surface of machined CP-Ti after GB/AC treatment, whereas a uniform net-like pattern formed after GB/AH treatment. In descending order, the surface roughness was GB, GB/AC, and GB/AH. The GB/AH group showed the highest SBS among all the treatments. As for primers, ALP group showed the highest SBS, while the RCP group showed the lowest. GB followed by ALP presented the highest SBS. CONCLUSION: A fine, uniform network structure was formed on the surface of CP-Ti following GB/AH treatment, providing an effective micromechanical interlocking mechanism for resin bonding. At the same time, after AH treatment, the -OH formed on the surface of the machined CP-Ti triggered a chemical reaction with the acid monomers in the resin adhesives, creating a chemical bond. As a result, GB/AH treatment significantly improved the bond strength relative to GB/AC treatment. In addition, ALP treatment facilitated the formation of hydrogen bonds, which further improved the chemical bond strength. Finally, the combination of the effects mentioned above resulted in the most robust bond between machined CP-Ti and the resin adhesives.


Asunto(s)
Recubrimiento Dental Adhesivo , Cementos de Resina , Cementos Dentales , Grabado Dental , Análisis del Estrés Dental , Ensayo de Materiales , Resistencia al Corte , Propiedades de Superficie , Titanio
9.
Photobiomodul Photomed Laser Surg ; 37(8): 465-472, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31390314

RESUMEN

Objective: The purpose of this study was to evaluate the effects of Er,Cr:YSGG laser irradiation with different energy powers versus sandblasting for enhancing the tensile bond strength (TBS) between titanium implant abutments (IAs) and resin cements. Background data: Clinical decementation of prosthetic restorations often occurs, particularly on short IAs. Increasing the bonding area on the IA surface can enhance the function and longevity of the superstructure. Materials and methods: Fifty dental IAs were used in solid form and randomly assigned to five groups (n = 10 each) for the following different pretreatments: control group was left untreated, a laser operating at 2.78 µm wavelength with different energy powers (1, 2, and 3 W) was used for three laser groups, and 50 µm alumina particles were applied to the abutment surface for the sandblasting group. Fifty metal substructures that had an occlusal metal O-ring were cast and cemented to all abutments using dual-cure resin cement. Test specimens were then subjected to thermal cycling. TBS tests were performed with a universal testing machine. The specimens' surface topography and roughness were evaluated with scanning electron microscope, and energy dispersive spectroscopy (EDS) was used to measure the elemental profiles of each specimen. Data were analyzed using a one-way analysis of variance/Kruskal-Wallis test at a significance level of p < 0.05. Results: Surface treatments affected the surface roughness and TBS of the IA. The sandblasting group showed the highest bond strength values (510.77 ± 60.86 N) and followed by the 2 W group (279.07 ± 37.9 N). In EDS analysis, no elemental components other than titanium and oxygen were observed, except for in the sandblasting group. Conclusions: Sandblasting and 2 W laser treatment increased the surface roughness of the IA, which could contribute to the increased interfacial bond strength between the IA and resin cement.


Asunto(s)
Pilares Dentales , Recubrimiento Dental Adhesivo/métodos , Grabado Dental/métodos , Láseres de Estado Sólido , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Distribución Aleatoria , Cementos de Resina/química , Espectrometría por Rayos X , Propiedades de Superficie , Resistencia a la Tracción , Titanio/química
10.
BMC Oral Health ; 19(1): 178, 2019 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-31387557

RESUMEN

BACKGROUND: The aim of this study was to evaluate the effect of universal adhesives (UA) and silane on the microtensile bond strength (µTBS) of resin cement to a hybrid ceramic Vita Enamic (VE). METHODS: VE specimens were acid etched using hydrofluoric acid (HF) and were assigned to three groups (n = 10) based on the applied bonding technique. In group 1 (S), a silane-based primer was used as a surface treatment prior to the application of a resin cement (Variolink Esthetic DC). In group 2, a silane-containing UA, Clearfil Universal Bond (CUB) was used for the surface treatment, and in group 3, A silane-free UA, Tetric N-Bond Universal (TNU) was used for surface treatment. Resin cement build-ups were prepared. The bonded specimens were sectioned into resin-ceramic beams. Half of the beams of each group were stored for 24 h at 37 °C and the other half were subjected to a thermo-cycling aging. The microtensile bond strength (µTBS) was measured at a crosshead speed of 0.5 mm/min. Failure modes were assessed accordingly. Data were analyzed using a) two-way analysis of variance ANOVA followed by one-way ANOVA and Tukey tests between groups and b) independent t-test to detect differences (α = 0.05) for each group. The surface topographies of the ceramic surface were evaluated using scanning electron microscopy. RESULTS: The results showed that silane-based primer (S) application resulted in significantly higher (p < 0.05) µTBS values after 24 h and after thermocycling compared to both silane-containing UA (CUB) and silane-free UA (TNU). The µTBS values of all groups were significantly reduced after thermocycling. No statistically significant difference was observed between the µTBS of CUB and TNU after 24 h. However, TNU showed significantly higher µTBS after thermocycling. Different failure modes were observed, and adhesive failure was the most common in all groups. Marked surface topographic changes were observed following HF etching. CONCLUSION: It is concluded that, the UAs tested cannot be recommended as substitutes to the silanization of Hybrid ceramic.


Asunto(s)
Cerámica/química , Recubrimiento Dental Adhesivo , Cementos de Resina/química , Grabado Ácido Dental , Cementos Dentales , Grabado Dental/métodos , Porcelana Dental/química , Análisis del Estrés Dental , Estética Dental , Humanos , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Propiedades de Superficie , Resistencia a la Tracción
11.
Microsc Res Tech ; 82(10): 1668-1680, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31259458

RESUMEN

The study aimed at finding an optimal combination of acid concentration and etching time when nitric acid is used as etchant for the study of the finer details of human dental enamel structure. Four hundred 2-3-mm-thick segments of facio-lingually sectioned human third molar crowns were assigned to 20 groups with 20 specimens in each group, each group differing with respect to acid concentration (0.1, 1, 2.5, and 5%) and etching time (15, 30, 45, 90, and 180 s). After etching and preparation, specimens were observed in the scanning electron microscope (SEM). Surface roughness/topography increased with increasing acid concentration and increasing etching time, but not in a linear fashion; generally, prisms tended to go from flat-surfaced to cone-shaped and prism sheaths from fissure-like to wedge-shaped. Intragroup variations and intergroup similarities were considerable. The two major enamel factors determining the etch effect are crystal orientation and prism sheath properties. Other factors, such as distribution of porosities and crystal quality, also contribute probably. Slight to moderate topography is best for observing the finer enamel structure, for example, etching with concentrations in the range 0.1-1% and with etching times in the range 15-90 s, the stronger the acid, the shorter the time. The depth effect of nitric acid is judged to be relatively small. Considerable variations in expression of prism cross-striations were observed. SEM observations of acid-etched enamel in carefully selected planes are a powerful method for the study of enamel structure, bearing in mind the artifactual aspects of the observed surface.


Asunto(s)
Ácidos/metabolismo , Esmalte Dental/ultraestructura , Grabado Dental/métodos , Humanos , Microscopía Electrónica de Rastreo , Diente Molar/ultraestructura , Propiedades de Superficie , Factores de Tiempo
12.
Photobiomodul Photomed Laser Surg ; 37(7): 434-441, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31265377

RESUMEN

Objective: The purpose of this study is to investigate the effect of various presintering and sintered surface treatments and thermocycling on the bond strength between zirconia and veneer ceramics. Background data: Bond stability between zirconia and veneer ceramic is a major concern, and only limited evidence about its longevity is currently available. Moreover, no study has yet evaluated the influence of thermocycling on the bond strength of veneer ceramic to zirconia after Er,Cr:YSGG laser irradiation at different pulse durations and sandblasting. Materials and methods: In this study, 220 nonsintered zirconia specimens were prepared with CAD/CAM and randomly divided into 2 groups; half of the specimens in each group were stored in water for 1 week, and the other half were thermocycled (5000 cycles) between baths of 5°C and 55°C. Specimens were then divided into five subgroups based on the following surface treatments: control (untreated surface), sandblasting (120 µm Al2O3), and Er,Cr: YSGG laser irradiations (3 W-8 Hz, 3 W-15 Hz, and 3 W-20 Hz, MGG 6 laser tip, for 20 sec, distance of 10 mm, water/airflow of 55% and 65%). Morphological assessment was done using atomic force microscopy and scanning electron microscopy, and phase transformation was assessed by X-ray diffractometry. All specimens were then veneered with veneering ceramic, and bond strength test using a universal testing device at a 1 mm/min crosshead speed. Data were evaluated by Kruskal-Wallis variance analysis and the Mann-Whitney U test. Results: There was no significant difference in the bonding strength values among the (p > 0.05). Thermocycling reduced the bond strength, but it was not significant (p > 0.05), except for the presintering 20 Hz group (p < 0.02). Conclusions: Application of thermocycling to sintered zirconia specimens may be detrimental to the shear bond strength of zirconia ceramics. Treating the zirconia surface after sintering is not recommended, due to the decrease in bond strength.


Asunto(s)
Cerámica/química , Recubrimiento Dental Adhesivo/métodos , Grabado Dental/métodos , Materiales Dentales/química , Láseres de Estado Sólido , Resistencia al Corte/efectos de la radiación , Circonio/química , Diseño Asistido por Computadora , Coronas con Frente Estético , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Propiedades de Superficie
13.
Photobiomodul Photomed Laser Surg ; 37(7): 428-433, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31265378

RESUMEN

Objective: Evaluate the bond strength of repairs made on composite resin following the treatment of the surface of the flaw with different bonding agents and/or CO2 laser. Background: The influence of CO2 laser and its interaction with other bonding agents on the surface of the flaw is not yet known. In this study, CO2 laser was chosen to treat the surface of the flaw due to its capacity to promote irregularities on the surface that enhance mechanical micro-retention. Methods: A block was created with Vitra APS nanohybrid composite resin (color: A3; FGM, Joinville, Brazil) measuring 5 mm in width, length, and depth (volume: 125 mm3). The surface of the flaw was treated before the repair with an adhesive, silane bonding agent, and/or CO2 laser. Six specimens were created in composite resin for each group (total: n = 36): G1: resin+resin; G2: adhesive+resin; G3: laser+adhesive; G4: laser+silane+adhesive; G5: silane+adhesive; G6: laser+silane. After the repair, the surfaces of the fracture of all specimens, which were submitted to the microtraction test, were analyzed under an optical microscope. Bond strength values obtained according to the type of surface treatment were tabulated and submitted to the Kruskal-Wallis test. Dunn's test was used to compare means. Results: G3 and G4 had significantly higher bond strength values compared to all other groups tested. Adhesive fractures predominated in all groups. However, G3 and G4 had a higher percentage of cohesive fractures compared to the other groups. Conclusions: The application of CO2 laser as a surface treatment led to greater bond strength of composite resin repairs in comparison with the groups that only received treatment with a burr and silanization. The groups submitted to CO2 laser also had a significantly lower number of adhesive failures when submitted to the microtraction test.


Asunto(s)
Resinas Compuestas/química , Recubrimiento Dental Adhesivo , Esmalte Dental/efectos de la radiación , Grabado Dental/métodos , Materiales Dentales/química , Láseres de Gas , Dióxido de Carbono , Análisis del Estrés Dental , Recubrimientos Dentinarios/química , Ensayo de Materiales , Resistencia al Corte/efectos de la radiación , Estrés Mecánico , Propiedades de Superficie
14.
Photobiomodul Photomed Laser Surg ; 37(7): 442-450, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31265379

RESUMEN

Objective: This study compared the effects of different surface treatments on the surface roughness (Ra), and shear bond strength (SBS) of resin cement to yttria-stabilized tetragonal zirconia (Y-TZP) ceramic and nickel-chromium (Ni-Cr) base metal alloy, respectively. Materials and methods: Thirty disk-shaped specimens (3 mm height and 10 mm diameter) of each material (Y-TZP and Ni-Cr) were prepared. Both zirconia and metal specimens were randomly assigned to three equal groups, according to the surface treatments (n = 10): sandblasting, sandblasting + Er:YAG laser, and sandblasting + Nd:YAG laser. Resin cement cylinders (4 mm diameter and 3 mm thickness) were placed on each specimen. The SBS tests were performed at a 1 mm per minute crosshead speed through a knife-edge rod after 5000 thermal cycles. The Ra (µm) of the specimens was measured using a profilometer and evaluated topographically by atomic force microscopy and scanning electron microscopy. Analysis of variance, followed by Tukey's honestly significant difference, in addition to the Kruskal-Wallis test, followed by the Mann-Whitney U test, were used for statistical analysis (α = 0.05). Results: Combined sandblasting and laser treatment of the metal groups led to statistically higher Ra values than sandblasting alone (p < 0.05). For Y-TZP, there were no significant differences between the Ra values of the subgroups (p > 0.05). The SBS of the sandblasted metal group was significantly higher than the other two laser-irradiated groups, whereas the SBS of sandblasted zirconia was only significantly higher than the Nd:YAG laser-irradiated group (p < 0.05). Conclusions: Combined laser and sandblasting surface treatments resulted in rougher surfaces than sandblasting alone, especially for the metal specimens. Sandblasting, alone, improved the SBS of resin cement in both metal and zirconia, compared with the laser and sandblasting treatments, combined.


Asunto(s)
Aleaciones de Cromo/química , Aleaciones Dentales/química , Recubrimiento Dental Adhesivo/métodos , Grabado Dental/métodos , Porcelana Dental/química , Láseres de Estado Sólido , Cementos de Resina/química , Itrio/química , Circonio/química , Ensayo de Materiales , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Resistencia al Corte/efectos de la radiación , Propiedades de Superficie
15.
Acta Odontol Latinoam ; 32(1): 29-35, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31206572

RESUMEN

The aim of this study was to evaluate the deproteinization of primary enamel by analyzing etching pattern types, with and without the application of 5% NaOCl before acid etching with 37% H3PO4. Fifteen extracted human primary molars were randomly selected for the present in vitro study; 1mm x 1mm blocks were prepared and divided into two groups (n = 21). These groups were treated as follows: Group A- Acid Etching with 37% H3PO4 gel for 15 s; Group B- 5% NaOCl for 60 s + Acid Etching with 37% H3POfor 15 s. The specimens were prepared for scanning electron microscopy analysis. The images were evaluated for quality types I and II etching of the enamel surface using ImageJ software. Datasets were checked for normality by Kolgomorv-Smirnov test and the nonparametric unpaired Mann-Whitney test was applied. The mean surface area of type I and II etching pattern values was 1922.314 µm2for Group A and 3840.473 µm2Group B. We conclude that deproteinization with 5% NaOCl prior to acid etching can be used to increase the area of adhesion and the quality of the etching pattern.


Asunto(s)
Grabado Ácido Dental/métodos , Recubrimiento Dental Adhesivo , Proteínas del Esmalte Dental/efectos de los fármacos , Esmalte Dental/efectos de los fármacos , Materiales Dentales/farmacología , Ácidos Fosfóricos/farmacología , Hipoclorito de Sodio/farmacología , Diente Primario/efectos de los fármacos , Recubrimiento Dental Adhesivo/métodos , Esmalte Dental/ultraestructura , Proteínas del Esmalte Dental/ultraestructura , Grabado Dental , Humanos , Microscopía Electrónica de Rastreo , Desnaturalización Proteica , Cementos de Resina , Propiedades de Superficie , Diente Primario/ultraestructura
16.
J Oral Sci ; 61(2): 327-334, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31217383

RESUMEN

This study investigated bond strength of CAD/CAM-manufactured composite resin and ceramic veneers to a zirconia framework and analyzed the effect of treatments of veneer surfaces. A CAD/CAM resin-based (AVE) composite or lithium disilicate ceramic (IEC) block was used as the veneer material. AVE and IEC specimens were assigned to receive one of three surface treatments (n = 22): no surface treatment, acid-etching with 9.5% hydrofluoric acid gel, and airborne-particle abrasion with alumina particles. Zirconia disks and AVE or IEC specimens in each group were bonded with a resin-based luting agent, and shear bond strength of the specimens was measured at 0 and 20,000 thermocycles. Significant differences were assessed by the Steel-Dwass test for multiple comparisons and Mann-Whitney U-test (α = 0.05). As compared with other surface treatments, bond strengths were significantly higher at 0 and 20,000 thermocycles in the airborne-particle abraded AVE and acid-etched IEC specimens. Airborne-particle abrasion of the surface of AVE specimens increased bond strength between AVE veneers and zirconia frameworks, while hydrofluoric acid treatment enhanced bond strength between IEC veneers and zirconia frameworks.


Asunto(s)
Recubrimiento Dental Adhesivo , Grabado Ácido Dental , Cerámica , Resinas Compuestas , Grabado Dental , Ensayo de Materiales , Cementos de Resina , Resistencia al Corte , Silanos , Propiedades de Superficie , Circonio
17.
J Oral Sci ; 61(2): 343-350, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31217385

RESUMEN

The study aimed to compare the repair bond strength of aged composite and amalgam repaired with resin composite after various mechanical and adhesive surface treatments. Specimens were aged by thermal cycling (10,000 cycles, 5-55°C) and randomly subjected to one of three surface treatments: diamond bur abrasion, aluminum oxide air abrasion, or silica coating. Conventional bonding or a universal adhesive with incorporated silane was applied afterward (each n = 16) and resin composite was attached. In the control groups (each n = 16), resin composite was attached using one of the above adhesives without prior mechanical surface conditioning. After further thermal cycling, the shear bond strength (SBS) and failure modes were assessed. Statistical analyses were performed using ANOVA, Weibull statistics, two sample t-tests, and Chi2-test (P < 0.05). The SBS of the repaired amalgam was significantly lower than that of the composite and mechanical pretreatment significantly increased SBS. The universal adhesive significantly improved the SBS of the repaired amalgam compared to the conventional bonding agent and mechanical pretreatment increased the number of cohesive/mixed failures. Amalgam restorations may be repaired using resin composites, but the resulting SBS is lower than that obtained with composite.


Asunto(s)
Recubrimiento Dental Adhesivo , Resinas Compuestas , Cementos Dentales , Grabado Dental , Análisis del Estrés Dental , Ensayo de Materiales , Metacrilatos , Cementos de Resina , Resistencia al Corte , Propiedades de Superficie
18.
Photobiomodul Photomed Laser Surg ; 37(8): 483-488, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31081712

RESUMEN

Objective: The aim of this study was to assess the effect of Er;Cr:YSGG laser parameters (power and frequency) on the bond strength and color stability of lithium disilicate (LD) ceramics. Materials and methods: One hundred ten specimens of LD ceramic were fabricated following heat pressed technique. Fifty disks were randomly distributed into five groups according to types of surface treatment [hydrofluoric (HF) acid, L1S L2S, L1D, and L2D]. For all laser-treated groups, bond preparation settings were used with a gold hand piece using a MZ10 tip (Er;Cr:YSGG, water lase I plus; Biolase). After surface treatment, adhesive bond was applied, and after photopolymerization, a composite buildup was performed. To evaluate shear bond strength, a controlled force was applied until failure using a universal testing machine. Color stability was assessed for six groups (HF, L1S L2S, L1D, L2D, and control) of LD ceramic (shade A1, LT translucency) through the CIE L*a*b* system. Three specimens from each of the six groups were selected randomly for assessment of surface topography using scanning electron microscopy. Means and standard deviations were compared using analysis of variance and Tukey's post hoc test (p < 0.05). Results: The maximum and minimum mean bond strength were shown by the L2D group 19.95 ± 1.014 and L1S group specimens 14.68 ± 0.863, respectively. Highest mean ΔE was found in L2S group 8.17 ± 2.10 and the lowest mean ΔE was found in control group (no treatment) 0.11 ± 0.05. Conclusions: LD specimens lased (Er;Cr:YSGG) with 3.75 W power and 15 Hz frequency for 4 min showed bond strength comparable with HF acid samples, and color changes within acceptable range (ΔE 1.17). Laser treatment (Er;Cr:YSGG) at 3.75 W power and 15 Hz frequency for 4 min of LD ceramics appears to be clinically efficient, showing acceptable bond strength and color stability.


Asunto(s)
Cerámica/química , Recubrimiento Dental Adhesivo/métodos , Grabado Dental/métodos , Porcelana Dental/química , Láseres de Estado Sólido , Color , Análisis del Estrés Dental , Ácido Fluorhídrico , Técnicas In Vitro , Microscopía Electrónica de Rastreo , Resistencia al Corte , Propiedades de Superficie
19.
Photobiomodul Photomed Laser Surg ; 37(8): 473-482, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31081715

RESUMEN

Objective and background: Different surface treatments have been tested in composite repair studies. However, there is still no consensus on the most effective repair protocol. The aim of this study is to measure the roughness values of eight different surface treatments for the repair procedure, to examine the effect of each surface treatment and three different composites on the repair bond strength with and without silane, and to evaluate whether there is a correlation between bond strength and roughness. Methods: The blocks were prepared with Filtek Z550 (3M ESPE) for the roughness measurements and divided into eight groups according to surface treatments. The roughness values of the surface treatments were measured by a 3D scanning contact profilometer (Nanomap LS). For the shear test, further samples were prepared, aged, and divided into three subgroups for the repair procedure with Filtek Z550 (3M ESPE), Vertise Flow (Kerr, USA), and G-aenial Flo (GC, Japan) after the surface treatments. Then, the shear test was performed. The Kruskal-Wallis and Spearman's Correlation tests were used for statistical evaluation of the data. Results: Significant differences were found between surface treatments and composite resins in terms of bond strength (p < 0.05). There is no correlation between the roughness and bond strength values. Conclusions: In bond strength, surface topography is more important than the numerical value of roughness. In the repair of composite restorations, methods that are already in clinical practice and more practical can be used instead of methods that require additional costs and devices.


Asunto(s)
Resinas Compuestas/química , Recubrimiento Dental Adhesivo/métodos , Grabado Dental/métodos , Láseres de Estado Sólido , Recubrimientos Dentinarios , Ensayo de Materiales , Cementos de Resina , Resistencia al Corte/efectos de la radiación , Silanos/química , Propiedades de Superficie
20.
Dent Mater ; 35(6): e107-e112, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30929767

RESUMEN

PURPOSE: The aim of this study is to evaluate the effect of fusion sputtering surface treatment on the microshear bond strength of zirconia and self-adhesive MDP-containing resin cement. MATERIALS: Thirty-six zirconia discs received one of the following treatments: fusion sputtering, airborne particle abrasion with 50-µm aluminum oxide particles, while as-sintered specimens served as a control. Four treated zirconia samples from each group were examined using 3D laser scanning microscope to assess the surface roughness and scanning electron microscope to study the surface topography. The specimens of each group were bonded to composite micro discs using MDP-containing self-adhesive resin cement (Panavia SA cement plus). The specimens were thermocycled for 5000 cycles between 5 and 55 °C. Microshear bond strength test was performed using universal testing machine until bonding failure. Failure modes and fracture surfaces was evaluated using scanning electron microscope. RESULTS: The fusion sputtering surface treatment significantly influenced zirconia-resin bond strength (p < 0.001). The highest mean microshear bond strength value was observed in fusion sputtering treatment (23.18 ± 4.38). The lowest value was observed in as-sintered zirconia surfaces (7.23 ± 6.26). SIGNIFICANCE: Fusion sputtering surface treatment enhanced the microshear bond strength of zirconia and resin cement.


Asunto(s)
Recubrimiento Dental Adhesivo , Cementos de Resina , Óxido de Aluminio , Grabado Dental , Ensayo de Materiales , Resistencia al Corte , Estrés Mecánico , Propiedades de Superficie , Circonio
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