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1.
Stomatologiia (Mosk) ; 99(2): 17-20, 2020.
Artículo en Ruso | MEDLINE | ID: mdl-32441070

RESUMEN

OBJECTIVE: To assess the degree of influence of human blood plasma simulating dentinal fluid on the composite resin adhesion to dental hard tissues. MATERIAL AND METHODS: The strength of the adhesive bond between the composite material and dental hard tissues was studied using a shear test machine Zwick Roell Z 010 («Zwick¼, Germany) on extracted human teeth. XP Bond one-component adhesive system and XENOV self-etching adhesive system (DENTSPLY, Germany), high-definition micrometric restoration material Esthet X HD (DENTSPLY, Germany), as well as centrifuged blood plasma were used. RESULTS: Adhesion strength decreased by 26-78% when blood plasma weighing from 0.2 to 2.0 mg mixed up the self-etching system (weight 6.6 mg). A significant decrease in the adhesion force occurred when plasma with a mass of 0.7 mg or more mixed up with the monomer (a decrease in adhesion by 19.1%). A critical decrease in the adhesion force (43% or more) occurred with the mixture of blood plasma weighing 2.0 mg or more.


Asunto(s)
Recubrimiento Dental Adhesivo , Grabado Ácido Dental , Resinas Compuestas , Cementos Dentales , Análisis del Estrés Dental , Humanos , Ensayo de Materiales , Cementos de Resina , Resistencia al Corte , Propiedades de Superficie
2.
J Adhes Dent ; 22(2): 183-193, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32322839

RESUMEN

PURPOSE: To determine the effect of Weibull analysis with censoring of cohesive failures on the evaluation of the effect of surface treatment and adhesive on the microtensile composite-composite bond strength. MATERIALS AND METHODS: Surfaces of Filtek Z250 (3M Oral Care) specimens aged in distilled water for five months at 37°C were ground with SiC paper P320 or air abraded with Al2O3 and built up with the same composite using Optibond FL (OPF, Kerr), Clearfil SE Bond (CSE, Kuraray Noritake) and Gluma Comfort Bond (GLU, Kulzer) adhesives. After sectioning and trimming, the specimens were stored at 37°C in distilled water for 24 h and then tested in a microtensile bond strength setup. Complete datasets of all strength data and adhesive datasets containing adhesively failed specimens were analyzed with a one-way Welch ANOVA at α = 0.05 and compared with the results of Weibull analysis applied on complete and adhesive datasets as well as complete datasets right censored for cohesive failures. Weibull shape (m) and scale (σo) parameters were estimated using the maximum likelihood method and used to calculate bond strength (σ0.10) at 10% probability of failure as a measure of system performance. The surface morphology was studied using light and scanning electron microscopy. RESULTS: While ANOVA indicated a significant effect of surface treatment and non-significant effect of the adhesive, the Weibull analysis results depended on bond strength characteristics and censoring. The scale parameter of the complete dataset indicating a significant effect of surface treatment for all adhesives became statistically non-significant for CSE after censoring. When this effect was evaluated by σ0.10, the non-significant effect of surface treatment for OPF and GLU became statistically significant due to censoring. The effect of the adhesive evaluated by the scale parameter was non-significant both for surfaces as well as complete and censored datasets. On the other hand, s0.10 suggested significant differences between adhesives on the ground surface for complete datasets which became statistically non-significant for the censored datasets. CONCLUSION: This study indicates that the results of statistical evaluation of bond strength can be affected not only by the experimental set-up and statistical model but also the bond strength characteristics and the manner in which the strengths of cohesively failed specimens are included in calculations.


Asunto(s)
Recubrimiento Dental Adhesivo , Grabado Ácido Dental , Cementos Dentales , Ensayo de Materiales
3.
J Adhes Dent ; 22(1): 99-105, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32030380

RESUMEN

PURPOSE: To use shear bond strength (SBS) and shear fatigue strength (SFS) testing to determine the durability of adhesion of self-adhesive restorative materials compared to composite resin bonded with a universal adhesive. MATERIALS AND METHODS: A universal adhesive, Prime & Bond Active, was used in self-etch mode to bond Z-100 composite resin to enamel and dentin. Three commercially available restorative materials and one experimental material with self-adhesive properties, Activa (A), Fuji II LC(F), and Equia Forte (E) and ASAR-MP4 (S) were also bonded to enamel and dentin. The SBS and SFS were determined for all materials. A staircase method was used to determine the SFS with 10 Hz frequency for 50,000 cycles or until failure occurred. RESULTS: On enamel, S generated similar values to the adhesive/composite materials and higher values than F, E, and A. On dentin, the composite/universal adhesive showed significantly higher SBS and SFS than the self-adhesive materials. S, F, and E generated higher values than A on dentin. CONCLUSION: SBS and SFS values to enamel were similar for all materials tested except Activa which generated lower enamel values. On dentin surfaces, the self-adhesive materials generated similar SBS and SFS, with the exception of Activa. Those values were lower than that generated with composite resin and a universal adhesive.


Asunto(s)
Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios , Grabado Ácido Dental , Cementos Dentales , Esmalte Dental , Análisis del Estrés Dental , Dentina , Ensayo de Materiales , Cementos de Resina , Resistencia al Corte
4.
Oral Health Prev Dent ; 18(1): 71-76, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32051973

RESUMEN

PURPOSE: The aim of this in vitro study was to evaluate the influence of preapplication of 2% chlorhexidine gluconate on the immediate microtensile bond strength of a universal adhesive system on dentine subjected to different bonding protocols. MATERIALS AND METHODS: Twenty human molars were used in this study, and the tooth surface was abraded to expose the dentine. The teeth were randomly divided into four groups according to the surface treatment (n = 5): SBU group: Single Bond Universal without acid etching; SBUPA group: 37% phosphoric acid + Single Bond Universal; SBUCG group: 2% chlorhexidine gluconate + Single Bond Universal; and SBUPACG group: 37% phosphoric acid + 2% chlorhexidine gluconate + Single Bond Universal. The microtensile bond strengths were measured using a microtensile tester 24 h after bonding. The bond strength data were subjected to analysis of variance (ANOVA) and Sheffé's least statistically significant difference test (α = 0.05). RESULTS: No statistically significant differences between the analysed groups were observed (p > 0.05). However, conditioning with phosphoric acid without the action of the chlorhexidine gluconate group resulted in higher numerical values of bond strengths than that for the chlorhexidine gluconate without the acid conditioning group. CONCLUSION: The preapplication of 2% chlorhexidine gluconate did not reduce the immediate bond strength of the Single Bond Universal adhesive system under different bonding protocols.


Asunto(s)
Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios , Grabado Ácido Dental , Clorhexidina/análogos & derivados , Resinas Compuestas , Cementos Dentales , Dentina , Humanos , Ensayo de Materiales , Proyectos Piloto , Propiedades de Superficie , Resistencia a la Tracción
5.
Rev. ADM ; 77(1): 22-27, ene.-feb. 2020. ilus, graf
Artículo en Español | LILACS | ID: biblio-1087921

RESUMEN

Introducción: Hoy en día, la mayoría de los pacientes requieren tratamiento de ortodoncia fija convencional, la cual utiliza procedimientos adhesivos afines con la superficie amelodentinaria. Aunque existen diferentes técnicas adhesivas que pueden ofrecer adecuados niveles de resistencia al desalojo, el uso del hipoclorito de sodio (NaClO) como agente desproteinizante no ha sido bien definido en materiales de cementación en aparatología ortodóncica convencional. Objetivo: El objetivo de este estudio fue determinar los niveles de resistencia al desalojo con pruebas de microtensión y análisis topográfico con microscopia electrónica de barrido. Material y métodos: 20 bloques de esmalte bovino fueron expuestos superficialmente a soluciones acondicionadoras (ácido ortofosfórico al 37%) con y sin agente desproteinizante (NaClO al 5.25%); finalmente, brackets individuales de ortodoncia fueron cementados con sistemas adhesivos y resinas compuestas de casas comerciales (Ormco y 3M). Las pruebas de resistencia al desalojo fueron realizadas con una máquina de fuerzas universales y el análisis topográfico con microscopia electrónica de barrido. Resultados: El uso del NaClO al 5.25% y la marca Ormco tuvieron estadísticamente los mejores niveles de adhesión que el grupo sin desproteinización y la casa comercial 3M, respectivamente. La topografía adamantina expuesta al agente desproteinizante mostró características de superficie relacionadas con el patrón de grabado tipo I. Conclusión: El uso de un agente desproteinizante (NaClO 5.25%) así como una marca comercial (Ormco) en particular podrían definir el aumento en los niveles de adhesión en superficies adamantinas con aparatología ortodóncica convencional (AU)


Introduction: Nowadays, patients require conventional fixed orthodontic treatment, which uses adhesive procedures related to the dentinal denture surface. Although there are different adhesive techniques that can offer adequate levels of bonding resistance, the use of NaClO as a deproteinizing agent has not been well defined in cementing materials in conventional orthodontic appliances. Objective: The objective of this study was to determine the levels of bond resistance using micro tension tests and topographic analysis with scanning electron microscopy. Material and methods: Twenty-blocks of bovine enamel were exposed superficially to conditioning solutions (37% orthophosphoric acid) with and without deproteinizing agent (5.25% NaClO); finally, individual orthodontic brackets were cemented with adhesive systems and resin composites of different trademarks (Ormco and 3M). Bonding resistance tests were performed with a universal force machine and topographic analysis was made with scanning electron microscopy. Results: The use of 5.25% NaClO and the Ormco brand had statistically better levels of adhesion than the group without deproteinization and the 3M brand, respectively. Adamantine topography exposed to the deproteinizing agent showed surface characteristics related to the type I etching pattern. Conclusion: The use of a deproteinizing agent (NaClO 5.25%) as well as a trademark (Ormco) in particular conditions could define the increase in adhesion levels on adamantine surfaces with conventional orthodontic appliances (AU)


Asunto(s)
Hipoclorito de Sodio/química , Grabado Ácido Dental , Recubrimiento Dental Adhesivo , Soportes Ortodóncicos , Esmalte Dental/efectos de los fármacos , Ácidos Fosfóricos , Propiedades de Superficie , Resistencia a la Tracción , Técnicas In Vitro , Microscopía Electrónica de Rastreo , Estudios Transversales , Análisis Estadístico , Resinas Compuestas
6.
J Biol Regul Homeost Agents ; 34(1 Suppl. 1): 49-54, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32064835

RESUMEN

Though the literature reports a well-documented scientific evidence of the performance of modern adhesive systems on normal dentin, few researches are available on the interaction between adhesives and compromised dentin. In this study, the authors analyzed the microscopic structural aspects of the adhesive interface on two common altered dentin substrates: dentin contaminated by metallic oxides and caries affected dentin. Thirty teeth were selected and divided in three groups of ten teeth according to the different dentin substrate they had: (A) normal dentin, (B) caries-affected dentin and (C) dentin contaminated by metallic oxides. The experimental cavity preparation was realised exposing in each sample, portion of pathologic dentin and portion of sound dentin as control. Each cavity was restored with micro-hybrid composite, with total etching and a two-step adhesive system. Each sample was sectioned in two halves analysed with two SEM micro-morphological methods: direct observation and decalcification. SEM investigations were able to show the difference in thickness and morphology of the adhesive interface with the two different dentin variables. Caries affected dentin determined the formation of less distinctive resin tags with few micro-tags. Discoloured dentin showed a poor infiltration with few resin tags probably due to alterations in the tubular structures. The micro-morphological variability of dentin substrate influences the clinical efficacy of bonding restorations determining significant differences in the qualitative and quantitative aspects of resin tags.


Asunto(s)
Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios , Dentina , Microscopía Electrónica de Rastreo , Grabado Ácido Dental , Resinas Compuestas , Humanos , Cementos de Resina
7.
Int J Paediatr Dent ; 30(4): 405-420, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31990108

RESUMEN

BACKGROUND: Children with first permanent molar affected by molar-incisor hypomineralization (MIH) show high treatment failure rate. AIM: To conduct a systematic review on bonding of adhesive materials to MIH-affected enamel, so as to identify all the methods suggested to optimize it and to determine the best bonding protocol(s). DESIGN: An exhaustive literature search was conducted on MEDLINE/PubMed, the Cochrane Library, and Web of Science databases, up to October 2018. Laboratory and clinical studies, involving adhesive restorations bonded to MIH-affected enamel, with at least a comparative group were included. Two authors independently selected studies, collected data, and assessed bias risk. RESULTS: After title and abstract review and duplicate exclusion, 14 articles were selected on the 496 eligible papers. After full reading, 4 articles were excluded. Finally, 10 studies (6 laboratory and 4 clinical studies) were included. CONCLUSIONS: Bond strength of composite was not significantly different when using self-etch compared with etch-and-rinse adhesives. Deproteinization after etching for etch-and-rinse adhesives enhanced bond strength; this could allow to keep MIH-affected enamel. Icon® showed an erratic penetration; however, a preliminary deproteinization after etching could improve bond strength. A study reported no significant differences in sealant retention rate, whereas another recommended to previously apply an adhesive.


Asunto(s)
Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios , Grabado Ácido Dental , Niño , Resinas Compuestas , Cementos Dentales , Esmalte Dental , Humanos , Incisivo , Ensayo de Materiales , Diente Molar , Cementos de Resina , Resistencia al Corte
8.
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
9.
J Oral Sci ; 62(1): 48-51, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31996522

RESUMEN

Although there have been improvements in bracket systems precoated with adhesive, removal of adhesive remnants continues to be problematic. This study compared the hardness and maintainability of precoated adhesive with other commercial adhesives. Knoop hardness values were measured after light- or chemical-induced initial curing, immersion in distilled water at 37°C for 24 h and 1,000 and 10,000 thermal cycles after 24 h. Additionally, the forces required to move brackets by 0.5 mm were measured during bracket positioning, and brackets bonded to bovine enamel were examined by field-emission scanning electron microscopy. The Knoop hardness values of the precoated adhesives were lower than those of commercial resin composite adhesives, and hardness was dependent on the amount of filler in the resin matrix. The ability to maintain the device position may depend on the resin matrix composition. Precoated adhesives with less filler and more matrix material are light curable, and remnant resin may be easily removed.


Asunto(s)
Recubrimiento Dental Adhesivo , Soportes Ortodóncicos , Grabado Ácido Dental , Adhesivos , Animales , Bovinos , Cementos Dentales , Dureza , Ensayo de Materiales , Cementos de Resina , Propiedades de Superficie
10.
J Prosthodont Res ; 64(3): 272-280, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31952931

RESUMEN

PURPOSE: The purpose of this study was to evaluate the effect of pretreatment using phosphoric acid, sodium hypochlorite and sulfinic acid sodium salt on the bonding of one-step self-etching adhesives to root canal dentin. METHODS: Thirty-six single-rooted sound human premolars were randomly assigned into three groups before applying the one-step self-etching adhesive. These comprised a control group with no pretreatment, an NC group that received phosphoric acid and subsequent sodium hypochlorite gel pretreatments, and an NC+AC group that received an additional treatment with sulfinic acid sodium salt following the same pretreatment applied to the NC group. Microtensile bond strength measurements, bonding interface observations by scanning electron microscopy (SEM), elemental analyses by X-ray photoelectron spectroscopy (XPS) and degree of polymerization (DOP) analyses by Raman spectroscopy were subsequently performed. RESULTS: The bond strength was significantly higher in the NC+AC group than in the other two groups (Control: P=000.1 and NC: P=0.004). SEM observations showed that resin tags were present in the dentinal tubules in the NC and NC+AC groups. Compared to the control group, the adhesive resin layer had a lower DOP in the NC group, while the DOP for the NC+AC group was higher than that of the NC specimens. CONCLUSIONS: Bonding to root canal dentin was improved by applying sulfinic acid sodium salt in addition to treatment with phosphoric acid followed by sodium hypochlorite. The DOP of the adhesive resin was reduced by sodium hypochlorite and subsequently restored by applying sulfinic acid sodium salt.


Asunto(s)
Recubrimiento Dental Adhesivo , Hipoclorito de Sodio , Grabado Ácido Dental , Resinas Compuestas , Cavidad Pulpar , Dentina , Recubrimientos Dentinarios , Humanos , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Ácidos Fosfóricos , Cementos de Resina , Sodio , Propiedades de Superficie , Resistencia a la Tracción
11.
Dent Mater J ; 39(3): 407-414, 2020 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-31932548

RESUMEN

The purpose of this study was to evaluate the effects of two different concentrations of silver diammine fluoride (SDF) on dentin bonding performance. Human mid-coronal dentin was treated with either distilled water (control), 3.8%SDF or 38%SDF for 3 min. A two-step self-etch adhesive and resin composite were applied according to manufacturer's instructions. After thermocycling (TC) at 0, 5,000 and 10,000 cycles, microtensile bond strength (µTBS) testing and morphological assessment of resin-dentin bonding interface were performed. At 0 TC, µTBSs of 3.8% and 38%SDF were significantly reduced (p<0.05). At 5,000 and 10,000 TC, µTBSs of 3.8%SDF were comparable to those of the control group, whereas the µTBSs of 38%SDF were significantly lower (p<0.05). Acid-base resistance zone formation was observed in all groups, however, slope-shaped formation was identified only in the SDF groups. The µTBSs and interfacial morphology were influenced by concentration of SDF and also TC.


Asunto(s)
Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios , Grabado Ácido Dental , Amoníaco , Cementos Dentales , Dentina , Fluoruros , Humanos , Ensayo de Materiales , Cementos de Resina , Compuestos de Plata , Resistencia a la Tracción
12.
Clin Oral Investig ; 24(2): 711-718, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31127428

RESUMEN

OBJECTIVE: To evaluate the effect of Er:YAG etching on topography, microstructure, compressive strength, and shear bond strength (SBS) of All-Bond Universal adhesive to mineral trioxide aggregate-Angelus (AMTA) and Biodentine (BD). METHODS AND MATERIALS: Sixty cylindrical specimens of each cement (AMTA and BD) in five groups were prepared and stored for 72 h. The control groups were non-etched, and four other groups were acid-etched and laser-etched with a pulse energy of 60, 80, or 100 mJ, followed by compressive strength testing. Surface micromorphology and topography were evaluated. Similar groups were bonded using All-Bond Universal with self-etch and etch-and-rinse (acid-etch) approaches, and laser-etch 60, 80, and 100 mJ, and SBS was tested. Data were analyzed using two-way and one-way ANOVA and the Bonferroni post hoc tests (α = 0.05). RESULTS: BD had a significantly higher compressive strength and SBS (except for laser-etch 100) compared to AMTA, regardless of the etching method (p < 0.001). Acid etching and laser etching 100 of both cements and laser etching 80 of BD alone produced a significantly lower compressive strength than that for the other groups. Contrary to BD, for AMTA, all the treatments significantly increased SBS compared to that of the self-etch group. CONCLUSIONS: Etching of AMTA was needed for stronger bonding; laser etching with 60 or 80 mJ without compromising compressive strength was recommended. Etching not only did not improve bonding ability of BD, but it also negatively affected the strength of BD. CLINICAL RELEVANCE: To achieve successful combined calcium silicate cement-resin material restoration, an adequate bond between the materials is mandatory. This might be provided with the ultramild adhesive through laser etching without compromising compressive strength, depending on cement composition and laser energy level used.


Asunto(s)
Fuerza Compresiva , Recubrimiento Dental Adhesivo , Láseres de Estado Sólido , Grabado Ácido Dental , Compuestos de Calcio , Cementos Dentales , Ensayo de Materiales , Resistencia al Corte , Silicatos , Propiedades de Superficie
13.
Oper Dent ; 45(1): 80-91, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31226005

RESUMEN

OBJECTIVE: The purpose of this study was to evaluate whether different enamel etching methods with reduced etching times would improve the bonding effectiveness of universal adhesives. METHODS AND MATERIALS: Three enamel etching methods, phosphoric acid ester monomer (PPM) etching, phosphoric acid (PPA) etching, and polyalkenoic acid (PLA) etching, and three universal adhesives, G-Premio Bond (GP), Prime&Bond elect (PE), and Scotchbond Universal Adhesive (SU), were evaluated. Initial bond strengths and fatigue strengths of universal adhesives to ground enamel and ground enamel etched for less than one, five, 10, and 15 seconds using different etching methods were determined. The bonded fatigue specimens were loaded using a sine wave at a frequency of 20 Hz for 50,000 cycles or until failure occurred with a staircase method. Atomic force micrograph (AFM) observations along with measurements of surface Ra roughness and modified surface area of enamel with different etching protocols were also conducted. RESULTS: The bond fatigue durability of universal adhesives to enamel with PPA etching from less than one to 15 seconds and PLA etching for 15 seconds was significantly higher than that to ground enamel. The bond fatigue durability to enamel with PPM etching was not increased compared with ground enamel. The surface Ra roughness and surface area obtained with AFM of enamel increased after PPA and PLA etching, and those values were significantly higher than those of ground enamel. Furthermore, surface Ra roughness and surface area with PPA etching were significantly higher than those with PLA etching. However, surface Ra roughness and surface area of enamel with PPM etching were similar to those of ground enamel regardless of etching time. CONCLUSION: PPA etching for less than one to 15 seconds and PLA etching for 15 seconds improve universal adhesive bonding, surface Ra roughness, and surface area of enamel. However, PPM etching is not effective, regardless of etching time, in improving bonds strengths, increasing surface roughness, and increasing surface area.


Asunto(s)
Grabado Ácido Dental , Recubrimiento Dental Adhesivo , Cementos Dentales , Esmalte Dental , Ensayo de Materiales , Ácidos Fosfóricos , Cementos de Resina , Resistencia al Corte , Propiedades de Superficie
14.
Oper Dent ; 45(2): 183-195, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31567054

RESUMEN

We attempted to determine the effect of universal adhesive application time on dentin bond performance in different etching modes based on shear bond strength (SBS) tests and surface free energy (SFE) measurements. The five universal adhesives used were Adhese Universal (AU), Clearfil Universal Bond Quick (CQ), G-Premio Bond (GP), Scotchbond Universal (SU), and Tokuyama Universal Bond (TU). Bovine dentin specimens were divided into four groups of 10 for each adhesive. SBS and SFE were determined after applying the following surface treatments: 1) self-etch (SE) mode with immediate air blowing after adhesive application (IA treatment), 2) SE mode with prolonged application time (PA treatment), 3) etch-and-rinse (ER) mode with IA treatment, and 4) ER mode with PA treatment. Bonded specimens were subjected to SBS testing. The SFE of adhesive-treated dentin surfaces was measured after rinsing with acetone and water. Three-way analysis of variance revealed that dentin SBS values (p<0.001) were significantly influenced by the factors of adhesive type and application duration, but the factor of pre-etching was not significant (p=0.985). The manufacturer's instructions require longer application times for AU and SU, which showed significantly lower SBS values in IA than in PA treatment in both etching modes. However, the difference in the other adhesives was not significant between the IA and PA treatments in either etching mode. The total SFE (γS) was dependent on the adhesive and etching mode. The γS value of the initial group (SiC paper ground group) at baseline was 69.5 (mN·m-1) and that of the pre-etching group at baseline was 30.6 (mN·m-1). For all the adhesives, γS in SE mode showed significantly higher values than in ER mode, regardless of the application time. In SE mode, almost all universal adhesives tested showed lower γS values in PA treatment than in IA treatment. For ER mode, all the adhesives showed significantly higher γS values than those of the pre-etching baseline, regardless of the application time. Most adhesives did not show any significant differences in γS values between IA and PA treatments, regardless of etching mode.


Asunto(s)
Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios , Grabado Ácido Dental , Adhesivos , Animales , Bovinos , Cementos Dentales , Dentina , Ensayo de Materiales , Cementos de Resina , Resistencia al Corte
15.
Oper Dent ; 45(1): E21-E31, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31794339

RESUMEN

OBJECTIVE: To evaluate the effect of hydrofluoric acid (HF) etching and thermocycling (Tc) on fatigue failure load of feldspathic ceramic restorations cemented with two resin cements. METHODS: Disc-shaped feldspathic ceramic (Vitablocs Mark II; Ø=10 mm, 1.0-mm thick) and G10 epoxy resin (Ø=10 mm, 2.5-mm thick) specimens were made and randomly allocated considering three factors: ceramic etching (ie, with vs without 10% HF plus silane application), resin cement (ie, self-adhesive [RelyX U200; U200] or conventional [Multilink Automix; MA]), and Tc (ie, with vs without 5-55°C/12,000 cycles). Adhesive cementation followed each manufacturer's instructions. The fatigue test (n=20) was based on the staircase approach (250,000 cycles; 20 Hz). Contact angle, surface topography, and fractography analysis were also executed. Specific statistical tests were employed for each outcome (α=0.05). RESULTS: The interaction of HF and Tc factors decreased the fatigue resistance for both cements (U200 542.63>U200/HF-Tc 495.00; MA 544.47>MA/HF-Tc 506.84). Comparing the cements associated with HF or Tc, there was statistical superiority for MA (U200-Tc 537.37

Asunto(s)
Cerámica , Recubrimiento Dental Adhesivo , Grabado Ácido Dental , Porcelana Dental , Análisis del Estrés Dental , Ácido Fluorhídrico , Ensayo de Materiales , Cementos de Resina , Propiedades de Superficie
16.
Oper Dent ; 45(2): 196-208, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31738692

RESUMEN

The aim of this study was to determine the effect of aluminablasting on the bond durability of universal adhesives and adherent surface characteristics. Adhese Universal (Ivoclar Vivadent), All-Bond Universal (Bisco), Bondmer Lightless (Tokuyama Dental), G-Premio Bond (GC), and Scotchbond Universal (3M ESPE) were used in self-etch mode. The prepared bovine enamel and dentin specimens were divided into two groups based on whether they received an aluminablasting prior to application of the universal adhesives. The resin composite bonded specimens were stored in distilled water at 37°C for 24 hours, following which the shear bond strength (SBS) of half of the specimens was measured (24-hour group). The other half was subjected to 30,000 thermal cycles between 5 and 55°C before SBS measurement (TC group). Surface roughness (Ra) and surface free energy (SFE) of the adherent surfaces were also measured, and scanning electron microscopy observation and scanning electron microscopy/energy-dispersive X-ray analysis were carried out. Most of the adhesives did not show any significant differences in enamel SBS values between the two pretreatment groups, regardless of the storage condition. However, the dentin SBS values were significantly lower in specimens that underwent aluminablasting compared with those that did not, irrespective of their storage conditions. Significantly higher Ra and SFE values were observed in the enamel and dentin of specimens that underwent aluminablasting. Although aluminablasting increased the Ra and SFE values of enamel and dentin, its effect on the SBS value was dependent on the tooth substrate. In addition to C, O, Na, Mg, P, and Ca, the element Al was detected in the enamel and dentin of samples that had undergone aluminablasting. These results suggest that although aluminablasting of the tooth surface is thought to be effective for modification of the adherent surface, it may not enhance enamel bond performance and may also adversely affect the dentin bond effectiveness of the universal adhesives.


Asunto(s)
Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios , Grabado Ácido Dental , Animales , Bovinos , Cementos Dentales , Ensayo de Materiales , Cementos de Resina , Resistencia al Corte , Propiedades de Superficie
17.
J Orofac Orthop ; 81(2): 79-88, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31853585

RESUMEN

PURPOSE: To assess the effect of the contact compressive force to seat orthodontic brackets on shear bond strength (SBS) and adhesive thickness using adhesive resins with different viscosities. METHODS: A total of 184 premolars were divided equally into eight groups of 23. Transbond XT and Beauty Ortho Bond paste viscous self-etching adhesive systems were used with contact compressive forces of 0.5, 1, 2, and 3 N (groups 1-4 and groups 5-8, respectively) via a push-pull tension gauge. SBS and adhesive thickness were measured in each adhesive system for each contact compressive force. RESULTS: Significant differences existed in the SBSs between the adhesive systems for each contact compressive force and the SBSs were significantly higher in groups 1 (17 MPa) and 2 (16 MPa) than in groups 3 (14 MPa) and 4 (13 MPa). Significant differences existed for the adhesive thickness between the adhesive systems for the three contact compressive forces less than 3 N. The adhesive in group 1 (0.184 mm) was significantly thicker than that in groups 2-4 (from 0.098 to 0.129 mm). In groups 2 (0.129 mm) and 3 (0.121 mm) it was thicker than in group 4 (0.098 mm), and in group 5 (0.119 mm) it was thicker than in groups 6-8 (from 0.087 to 0.088 mm). CONCLUSIONS: The high-viscosity adhesive Transbond XT exhibited higher SBSs than the low-viscosity Beauty Ortho Bond paste. For the adhesive Transbond XT, lower contact compressive forces produced greater adhesive thicknesses and higher SBSs. For the Beauty Ortho Bond paste, no significant changes in the adhesive thickness or SBS values were observed for contact compressive forces greater than 0.5 N.


Asunto(s)
Recubrimiento Dental Adhesivo , Soportes Ortodóncicos , Grabado Ácido Dental , Cementos Dentales , Análisis del Estrés Dental , Ensayo de Materiales , Cementos de Resina , Resistencia al Corte , Viscosidad
18.
Gen Dent ; 68(1): 22-28, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31859658

RESUMEN

Self-adhesive resin cements that eliminate the primer step have been introduced to simplify the bonding protocol for indirect restorations. The aim of the present study was to compare the shear bond strengths (SBSs) of 2 self-adhesive resin cements used with or without a self-etching primer. The hypothesis was that adding a separate primer component to the self-adhesive systems would increase the SBS at the tooth-adhesive interface. One hundred twenty extracted human molars were hemisectioned and embedded in epoxy. Specimens were polished to expose enamel or dentin surfaces and randomly assigned to 12 test groups (n = 20). The tested variables were (1) the type of bonded tissue (enamel or dentin); (2) the cement used; (3) whether the cement was applied with or without a primer; (4) and whether the primer was air dried or photopolymerized. Bonding jigs were used to apply the self-adhesive resin cement to the tooth surfaces. A 2-minute self-cure was followed by 20 seconds of light curing. Specimens were stored in water for 24 hours and then subjected to SBS testing in a universal testing machine. Fractured specimens were examined under a microscope to determine the modes of failure. Mean SBS values were compared using a paired Student t test (with post hoc Tukey test) and an analysis of variance (α = 0.05). Compared to the control groups, the air-dried primer groups showed SBSs that were 4-6 times greater for the specimens bonded to dentin and 2-3 times greater for specimens bonded to enamel. The photopolymerized primer groups followed the same trend. The photopolymerized groups showed higher percentages of cohesive tooth failure than did air-dried primer groups. Placement of a self-etching primer prior to a self-adhesive resin cement significantly increased the SBS to tooth structure of the "all-in-1" resin cements that were tested. Photopolymerizing the primer did not significantly increase the bond strength.


Asunto(s)
Recubrimiento Dental Adhesivo , Cementos Dentales , Ensayo de Materiales , Cementos de Resina , Resistencia al Corte , Grabado Ácido Dental , Cementos Dentales/química , Análisis del Estrés Dental , Dentina , Recubrimientos Dentinarios , Humanos , Cementos de Resina/química , Propiedades de Superficie
19.
Dent Med Probl ; 56(4): 343-348, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31794165

RESUMEN

BACKGROUND: The adhesion of composite resins to the dentin substrate is influenced by the treatment of the smear layer. While etch-and-rinse systems require dentin to be conditioned with phosphoric acid, self-etching systems preserve the smear layer by incorporating it into the adhesive layer. OBJECTIVES: The objective of this study was to evaluate the influence of etching with the rubbing technique on the microtensile bond strength (µTBS) of a universal adhesive to dentin. MATERIAL AND METHODS: Eighteen extracted teeth were selected. Two etch-and-rinse techniques (with and without rubbing) and a self-etching technique were used to bond the dentin surfaces with a universal adhesive system. After 24 h, the bonded samples were prepared for the µTBS testing. The specimens were loaded with a tensile force at a crosshead speed of 0.5 mm/min until failure. The scanning electron microscope (SEM) analyses were used to reveal the failure modes. The data were statistically analyzed with the one-way analysis of variance (ANOVA) and χ2 tests. RESULTS: The etch-and-rinse system with rubbing produced significantly lower bond strength (42.11 ±9.26 MPa,) than the etch-and-rinse system without rubbing (47.30 ±8.12 MPa) and significantly higher bond strength than the self-etching system (38.07 ±9.49 MPa). CONCLUSIONS: Under the conditions of this study, dentin etched with phosphoric acid for 3 s in the etchandrinse mode with the rubbing technique for a universal adhesive system decreases the µTBS of the composite to dentin.


Asunto(s)
Recubrimiento Dental Adhesivo , Dentina , Grabado Ácido Dental , Cementos Dentales , Recubrimientos Dentinarios , Ensayo de Materiales , Resistencia a la Tracción
20.
J Contemp Dent Pract ; 20(9): 1014-1018, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31797821

RESUMEN

AIM OF STUDY: Evaluation of the bond strength of the resin cement after enamel conditioning with erbium-doped yttrium aluminum garnet laser compared to other four different techniques. MATERIALS AND METHODS: The study consisted of 50 enamel specimens excluded from the smooth surfaces of newly extracted human 3rd molars. The specimens were randomly divided into five groups in terms of the enamel treatment technique. Each group (n = 10) was conditioned differently by bevel and acid etching group (I), acid etching technique group (II), double acid etching technique group (III), air abrasion followed by acid etching group (IV), and Er:YAG laser followed by acid etching group (V). After enamel treatment, a resin cylinder was installed using split Teflon matrix on each enamel specimen. Then the specimens were exposed to a shear strength device, and shear force was applied. The results were recorded with Newton. The required data were collected and statistically analyzed. A one-way ANOVA test was conducted to compare the five study groups using SPSS version 21 (p < 0.05). RESULTS: All groups showed high shear bond strength values ranging from 19.26 MPa (for group III) to 27.05 MPa (for group V). The enamel treatment with Er:YAG laser followed by acid etching gave the best results with significant differences compared to the other groups. CONCLUSION: Within the limitations of the present study, it can be concluded that the combination between the Er:YAG laser and the acid etching enhances the bond strength of resin cement with the enamel. CLINICAL SIGNIFICANCE: The use of Er:YAG laser followed by acid etching can be a successful technique for enamel conditioning and the results showed their superiority over the other groups.


Asunto(s)
Recubrimiento Dental Adhesivo , Láseres de Estado Sólido , Grabado Ácido Dental , Esmalte Dental , Humanos , Cementos de Resina , Resistencia al Corte
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