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1.
Lasers Med Sci ; 38(1): 51, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36689017

RESUMO

The aim of this study was to evaluate the effect of different surface treatments combined with laser irradiation on the shear bond strength of different CAD-CAM ceramics to composite resin. A total of hundred forty-seven ceramic specimens with thicknesses of 2.5 mm were prepared from three different CAD-CAM ceramics (an yttrium oxide partially stabilized tetragonal zirconia polycrystal (Y-TZP); a zirconia-reinforced lithium silicate glass ceramic (ZLS); and a lithium disilicate-strengthened lithium aluminosilicate glass ceramic (LD-LAS)) and subjected to seven groups of treatment (n = 7): (1) control (no treatment), (2) Er:YAG laser irradiation, (3) Nd:YAG laser irradiation, (4) etching with hydrofluoric acid (HFA), (5) Er:YAG + HFA, (6) Nd:YAG + HFA, and (7) sandblasting. After surface treatment procedures, a ceramic primer (Clearfil Ceramic Primer Plus, Kuraray, Japan) was applied to the ceramics. Bonding agent (Single Bond Universal Adhesive, 3 M ESPE, USA) was then applied, and the composite resin (Estelite Sigma Quick, Kuraray, Japan) was layered on the ceramic surfaces. The shear bond strength test was performed using a universal testing machine at a load of 0.5 mm/min. Data were analyzed by 2-way analysis of variance (ANOVA), and the Bonferroni correction was used for pairwise comparisons (α = 0.05). Compared to the bond strength of the control group, irradiation by Er:YAG and Nd:YAG lasers alone improved the bond strength of the composite resin to the Y-TZP (P < 0.001) but did not change the bond strength of composite resin to the ZLS and LD-LAS (P > 0.05). Compared to the bond strength of the control group, etching with HFA alone increased the bond strength of the composite resin to the ZLS and LD-LAS (P < 0.001) but did not affect the bond strength of the composite resin to the Y-TZP (P > 0.05). The highest bond strength of ZLS was obtained using HFA + Er:YAG, and the highest bond strength for LD-LAS was obtained using HFA + Nd:YAG. It was concluded that Er:YAG and Nd:YAG laser treatments presented the highest repair bond strength between the composite resin and Y-TZP ceramics. Er:YAG and Nd:YAG laser treatments in conjuction with HFA presented the highest repair bond strength between the composite resin and the glassy ceramics, ZLS, and LD + LAS.


Assuntos
Colagem Dentária , Lítio , Teste de Materiais , Propriedades de Superfície , Cerâmica/química , Zircônio/química , Porcelana Dentária , Resinas Compostas/química , Cimentos de Resina/química , Desenho Assistido por Computador , Lasers , Resistência ao Cisalhamento
2.
J Adhes Dent ; 25(1): 23-30, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36689275

RESUMO

PURPOSE: To investigate the bond durability of composite cement to zirconia after treatment with a 15-methacryloyloxypentadecyl dihydrogen phosphate (15-MPDP)-containing adhesive and 2 commercially available adhesives. MATERIALS AND METHODS: Ninety zirconia bars were fabricated and bonded to prepolymerized resin composite cylinders with a composite cement after surface treatment for 20 s using the following adhesives: Adper Easy One (AEO, negative control), Single Bond Universal (SBU, positive control), and 10 wt% 15-MPDP powder mixed with Adper Easy One (15- MPDP). After storage in distilled water at 37°C for 24 h, the specimens were divided into 3 subgroups according to the aging treatment applied (n = 10): no aging treatment (0/TC), 10,000 thermocycles (1/TC), and 37,500 thermocycles (3/TC). Shear bond strength (SBS) was analyzed using two-way ANOVA (p < 0.05), and the fracture surfaces were examined under a dental microscope. RESULTS: Significant differences in the SBSs among the surface treatments and aging treatments were observed (both p < 0.001). The 15-MPDP and SBU groups showed significantly higher SBSs than the AEO group, whereas similar SBSs were found in the 15-MPDP and SBU groups. Significant reductions in the SBSs were found after 37,500 thermocycles (p < 0.001), although no significant difference between specimens aged with 10,000 thermocycles and non-aged specimens was observed. CONCLUSIONS: The 15-MPDP-containing dental adhesive exhibited bond durability comparable to that of a well-established 10-MDP-containing universal adhesive. Aging by 10,000 thermocycles may be insufficient to disrupt the bond of composite cement to zirconia.


Assuntos
Colagem Dentária , Fosfatos , Propriedades de Superfície , Cimentos de Resina , Zircônio , Cimentos de Ionômeros de Vidro , Resistência ao Cisalhamento , Teste de Materiais
3.
Artigo em Inglês | MEDLINE | ID: mdl-36661887

RESUMO

This study evaluated shear bond strength (SBS) of thermally aged composite resins repaired using different surface protocols. Four-hundred composite resin samples were made using the following materials (100 samples per material): Filtek Z350XT (FXT); Spectra Smart (SSM); IPS Empress Direct (EDI); and Forma (FOR). Each group's samples were then divided into 10 groups (n = 10 samples per group): G1: no surface treatment; G2: phosphoric acid-etching + universal-adhesive (PU); G3: surface roughening + PU (RPU); G4: RPU + silane (RPSU); G5: surface roughening + hydrofluoric acid-etching + universal adhesive (RHU); G6: RHU + silane (RHSU); G7: dry sandblast + PU (DsPU); G8: DsPU + silane (DsPSU); G9: wet sandblast + PU (WsPU); and G10: WsPU + silane (WsPSU). G1 was freshly repaired, and G2 to G10 were thermally aged before repair. Specimens were tested for SBS, and the failure type was observed with a magnifying loupe. Representative images were obtained using a scanning electronic microscope. Data were analyzed by two-way analysis of variance and Tukey post hoc tests (P = .05). Differences were detected among different surface treatments and among different composite resins with equal surface treatments (P < .05). SBS means ranged from 10.48 (FOR:G2) to 20.70 (FXT:G7). The highest SBS values were seen in G7 to G10 (P > .05), while lowest values were generally observed for G2. G1 showed higher results compared to G2 (P < .05), except for EDI (P > .05). Most failures corresponded with cohesive type. In general, thermally aged composite resin presented a decreased repair bond strength potential when no additional surface treatment was applied. Sandblasting improved the SBS of repaired aged composite resins.


Assuntos
Resinas Compostas , Colagem Dentária , Humanos , Idoso , Resinas Compostas/química , Colagem Dentária/métodos , Silanos/química , Protocolos Clínicos , Propriedades de Superfície , Teste de Materiais , Resistência ao Cisalhamento , Cimentos de Resina/química , Análise do Estresse Dentário
4.
Int J Mol Sci ; 24(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36674917

RESUMO

There is a significant change in the bacterial plaque populations in the oral cavity during and after orthodontic treatment. Numerous studies have demonstrated that 2-96% of patients could increase the risk of white spot lesions. Streptococcus mutans and Lactobacilli ssp. are responsible for these white spot lesions. In this work, silver nanoparticles (AgNPs) with a diameter of 11 nm and dispersed in water were impregnated onto three different commercial orthodontic adhesives at 535 µg/mL. The shear bond strength (SBS) was assessed on 180 human premolars and metallic brackets. The premolars were divided into six groups (three groups for the commercial adhesives and three groups for the adhesives with AgNPs). All the groups were tested for their bactericidal properties, and their MIC, MBC, and agar template diffusion assays were measured. After adding AgNPs, the SBS was not significantly modified for any adhesive (p > 0.05), and the forces measured during the SBS did not exceed the threshold of 6 to 8 MPa for clinical acceptability in all groups. An increase in the bactericidal properties against both S. mutans and L. acidophilus was measured when the adhesives were supplemented with AgNPs. It was concluded that AgNPs can be supplement commercial orthodontic adhesives without modifying their mechanical properties with improved bactericidal activity.


Assuntos
Colagem Dentária , Cárie Dentária , Nanopartículas Metálicas , Humanos , Propriedades de Superfície , Nanopartículas Metálicas/química , Prata/farmacologia , Prata/química , Antibacterianos/farmacologia , Antibacterianos/química , Cimentos Dentários/farmacologia , Cárie Dentária/prevenção & controle , Resistência ao Cisalhamento , Teste de Materiais
5.
Sci Rep ; 13(1): 507, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36627322

RESUMO

This study aimed to evaluate the influence of the use of remineralizing agents on the tensile bond strength. The study sample consisted of 80 recently extracted molars, which were randomly divided into four experimental groups (n = 20): groups FG1 and FG30, in which fluoride varnish was used, and groups RG1 and RG30, in which Recaldent tooth mousse was used. The mesiobuccal surfaces served as experimental, and distobuccal as control (n = 80). Brackets were bonded to both surfaces and were submitted to a tension test at different time intervals (T1 and T30). Tensile bond strength (TBS) and the amount of adhesive remnant (ARI) were assessed. A statistically significantly lower mean of TBS compared to the control group was found only in the FG1 group (p < 0.001), and no significant difference was found between the other groups. The FG1 group showed significantly higher ARI scores (p < 0.001) compared to the control group. No significant difference was found between the other groups. In conclusion, bonding brackets one day after applying fluoride varnish significantly reduced the TBS, but after 30 days it was set back to an optimal value. The use of Recaldent before orthodontic treatment had no adverse effect.


Assuntos
Fluoretos Tópicos , Braquetes Ortodônticos , Fluoretos/farmacologia , Fluoretos/química , Fluoretos Tópicos/farmacologia , Fluoretos Tópicos/química , Teste de Materiais , Resistência ao Cisalhamento , Propriedades de Superfície , Resistência à Tração
6.
J Adhes Dent ; 25(1): 1-12, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36633468

RESUMO

PURPOSE: To evaluate the effect of plasma-enhanced chemical vapor deposition (PECVD) with silicon hydride (SiH4) at different times on HT-zirconia surface characteristics and bonding of composite cement before and after thermocycling. MATERIALS AND METHODS: Blocks of HT zirconia were obtained, polished, sintered and divided into five groups, according to PECVD time (n = 31): Zr-30 (30 s), Zr-60 (60 s), Zr-120 (120 s) and Zr-300 (300 s). The control group (Zr-0) did not receive PECVD. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), energy dispersive spectroscopy (EDS) in conjunction with field-emission scanning electron microscopy (FE-SEM), x-ray photoelectron spectroscopy (XPS), goniometry, and profilometry tests were used for chemical and topographic characterization. Monobond N silane (Ivoclar Vivadent) was applied to the surface, and a cylinder of composite cement (Variolink N) was made (3 x 3 mm). Half of the specimens of each group were stored for 24 h or subjected to thermocycling (6 x 103 cycles). A shear bond strength (SBS) test was performed. Results were subjected to one-way ANOVA and Tukey's tests (α = 0.05). RESULTS: For experimental groups, XPS showed that formation of Si-O bonds contributed to increased surface free energy (SFE). FE-SEM and EDS showed that the longer the deposition time, the greater the amount of silicon on the surface. Zr-60 and Zr-300 presented higher and lower surface roughnesses, respectively. The silicon penetrated the microstructure, causing higher stress concentrations. The bond strength to composite cement was improved after all PECVD deposition times. CONCLUSION: The PECVD technique with SiH4, associated with chemical treatment with primer based on silane methacrylate, is a solely chemical surface treatment capable of maintaining bonding between composite cement and HT zirconia.


Assuntos
Colagem Dentária , Silício , Silanos , Propriedades de Superfície , Cimentos de Resina , Cimentos Dentários , Zircônio/química , Resistência ao Cisalhamento , Teste de Materiais , Cerâmica/química
7.
BMC Oral Health ; 23(1): 17, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36635647

RESUMO

OBJECTIVES: Evaluating the bond strength of two ceramic materials to dentin after Er,Cr:YSGG laser debonding. Would laser debonding affect the bond strength of ceramic to dentin? MATERIALS AND METHODS: Recently extracted human molars were ground to expose dentin. Forty square shaped samples were prepared from CAD/CAM ceramic blocks. Samples were divided into two groups according to the type of ceramic material; group E: Lithium disilicate and group T: Ultra-translucent Zirconia (n = 20) Each group was divided into two subgroups (n = 10) according to the laser debonding effect (subgroup B: bonded samples, subgroup R: re-bonded samples after laser debonding). Ceramic samples were bonded to dentin using dual cure self-adhesive resin cement. Laser debonding of ceramic samples of subgroups R using Er, Cr:YSGG laser, were then re-bonded again to dentin surface with same resin cement. The Shear bond strength test using Universal testing machine was done. The failure mode was analyzed. Two-way analysis of variance was used to compare the mean bond strength and re-bond strength of two materials. The significance level was set at P ≤ 0.05. RESULTS: Two-Way ANOVA showed that ceramic type had a significant effect on the re-bond strength to dentin. The predominant failure mode was adhesive. CONCLUSIONS: Laser debonding of Lithium disilicate and Ultra translucent Zirconia decreased the re-bond strength to dentin. Deterioration in re-bond strength for Lithium disilicate ceramics was more pronounced than for Ultra translucent Zirconia. Clinical Relevance Deterioration in the bond strength between ceramics & dentin after laser debonding still needs improvement to allow its clinical use.


Assuntos
Colagem Dentária , Lasers de Estado Sólido , Humanos , Lasers de Estado Sólido/uso terapêutico , Cimentos de Resina/química , Cerâmica/química , Dentina , Teste de Materiais , Resistência ao Cisalhamento , Propriedades de Superfície
8.
Am J Dent ; 35(6): 275-283, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36508182

RESUMO

PURPOSE: To evaluate and compare the bonding of flowable resin composites and light-cured resin cements to dental ceramics. METHODS: Grit-blasted zirconia plates were primed with MDP-containing adhesive. Lithium disilicate glasses plates were etched with HF and primed with silane. Two flowable resin composites with high (CM: 75 wt%/62 vol%) and low (BF: 67.3 wt%/47 vol%) filler contents, and two resin cements, again with high (C: 72 wt%/69 vol%) and low (R: 66 wt%/47 vol%) filler contents, were bonded to both types of pretreated ceramics. Shear bond strength (SBS) was measured after 24 hours water storage or 10,000 times thermocycling between 5 and 55°C. The viscosities and film thicknesses of the four resin-based luting agents (RBLAs) were also explored by rotational rheometer and metallurgical microscope severally. RESULTS: Different RBLAs provided statistically different SBS values, with the high-filler specimens exhibiting higher SBS values than the low-filler specimens. The viscosities decreased in the order C > R > BF > CM. The film thicknesses for the BF and C groups were higher than those of the CM and R groups. CLINICAL SIGNIFICANCE: This study provides evidence that flowable resin composites with high filler contents and low viscosities may serve as an alternative to light-cured resin cements for luting zirconia or lithium disilicate glass. This expands the range of light-cured luting agents available for bonding of veneers or other thin restorations, which is of great benefit to clinical practice.


Assuntos
Colagem Dentária , Cimentos de Resina , Cimentos de Resina/química , Teste de Materiais , Cerâmica/química , Resinas Compostas , Zircônio/química , Cimentos Dentários/química , Resistência ao Cisalhamento , Propriedades de Superfície
9.
J Indian Prosthodont Soc ; 22(2): 179-187, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36511029

RESUMO

Aim: This study aims to evaluate the effect of different surface treatments of monolithic zirconia on the bond strength of resin to zirconia and, to explore alternative methods to improve this bonding. Settings and Design: In-Vitro study. Materials and Methods: Fifty rectangular sintered blocks of Yttria-stabilized Tetragonal Zirconia Polycrystal ceramics of dimensions were milled and sintered. These specimens were further divided into five groups (control, air abrasion, etching with primer application, air abrasion with primer application and novel glass infiltrated zirconia surface group), containing 10 samples each. The specimens were analyzed for surface roughness, tensile bond strength to resin cements, and adhesive and cohesive mode of failures. Statistical Analysis Used: ANOVA and Post-Hoc Tukey test was perform to evaluate the significant differences in the mean values of the groups. Results: Air-abraded samples showed the highest surface roughness (4.95 ± 0.65) (P < 0.05). The group with air abrasion followed by primer application showed the highest tensile bond strength (7.12 ± 0.69) (P < 0.05). The lowest surface roughness (0.638 ± 0.8093) and tensile bond strength (2.03 ± 0.58) was seen in samples that were subjected to etchant treatment followed by application of methacryloyloxydecyl di-hydrogen phosphate (MDP) primer. The changes in comparison to the control group were statistically insignificant (P > 0.05). Except Groups A (control) and C (etchant followed by primer), all other groups showed a cohesive failure. Conclusion: Air abrasion of the zirconia surface with 50 µm alumina particles increases the surface roughness without damaging the surface. Air abrasion followed by MDP primer application is the recommended method of surface treatment to achieve superior bonding. Glass infiltration also showed promising results in terms of tensile bond strength.


Assuntos
Colagem Dentária , Cimentos de Resina , Cimentos de Resina/química , Abrasão Dental por Ar/métodos , Colagem Dentária/métodos , Resistência ao Cisalhamento , Propriedades de Superfície , Teste de Materiais , Zircônio/química
10.
Niger J Clin Pract ; 25(12): 1949-1954, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36537449

RESUMO

Background: The effects of commonly used antimicrobial and anticariogenic agents on the adhesion of pit and fissure sealants were investigated in this study. Aims: The aim of this study is to evaluate the effects of erbium, chromium: yttrium-scandium-gallium-garnet (Er, Cr:YSGG) laser disinfection, casein phosphopeptides-amorphous calcium phosphate (CPP-ACP) containing paste and sodium hypochlorite application before the placement of a resin-based pit and fissure sealant on the shear bond strength of primary tooth enamel. Materials and Methods: The shear bond strength test evaluated the bond strength of sealants on the buccal enamel surfaces of primary molar teeth. The study groups were pit and fissure sealant without any preapplication, pre application of disinfection with Er, Cr:YSGG laser, disinfection with Er, Cr:YSGG laser and CPP-ACP containing paste, sodium hypochlorite, sodium hypochlorite and CPP-ACP containing paste and CPP-ACP containing paste. The pit and fissure sealants were placed using 4 mm diameter, 2 mm height cylindrical plastic tubes. Shear force was applied to each sample. The surfaces of the broken samples were detected under stereomicroscope and were grouped as adhesive, cohesive, and mixed. The results of the study were evaluated using the SPSS 16.0 package program for statistical analysis. Results: The groups where sodium hypochlorite and sodium hypochlorite with CPP-ACP were applied showed the lowest bond strength (p < 0.05). It was observed that most of the failures in these groups were adhesive-type failures. No significant difference was observed between the shear bond strengths of the other groups (p < 0.05). Conclusions: Er, Cr: YSGG laser and CPP-ACP containing paste are alternative methods for pre-application of fissure sealants.


Assuntos
Colagem Dentária , Lasers de Estado Sólido , Humanos , Caseínas , Hipoclorito de Sódio , Selantes de Fossas e Fissuras , Desinfecção , Adesivos , Resistência ao Cisalhamento , Teste de Materiais
12.
Lasers Med Sci ; 38(1): 4, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36538140

RESUMO

The effects of Er:YAG laser with different frequencies on zirconia ceramic's bonding properties were studied. In total, 42 Y-TZP (yttrium-stabilized tetragonal zirconia polycrystals, UPCERA ST) with 3 mm × 3 mm × 2 mm divided into 6 groups (n = 7): control (C), sandblasting (SB), and Er:YAG laser (A1-A4), which the frequencies correspond to 5 Hz, 10 Hz, 15 Hz, and 20 Hz, IPS e.max Press ceramics were B. Scanning electron microscope (SEM) images were recorded. The ceramics were bonded to enamel from extracted teeth. After being constantly stored at 37 ℃ for 24 h, the shear test was performed with a universal testing machine. Stereomicroscope evaluated fracture modes. Stereomicroscope evaluated fracture modes. Data were analyzed by SPSS26.0 statistical software; the standard was P = 0.05. (1) The SEM showed the surface of A1-A4 became rough compared with C. (2) The shear test showed that the highest bonding strength for B was 13.15 ± 2.97 MPa, followed by SB was 7.78 ± 0.97 MPa, and A2 was 7.13 ± 0.75 MPa. However, there was no significant difference between SB and A2 (P > 0.05). Fracture modes of C were the interface fracture of Y-TZP and resin adhesive; most of A1-A4 and SB also were interface fracture, a few mixed fractures, and cohesion fracture of resin adhesive; B were all mixed fracture. Er:YAG laser with 10 Hz could be used as an alternative to sandblasting with Al2O3 for surface modification of Y-TZP to increase the bonding strength.


Assuntos
Colagem Dentária , Lasers de Estado Sólido , Lasers de Estado Sólido/uso terapêutico , Teste de Materiais , Resistência ao Cisalhamento , Propriedades de Superfície , Cerâmica/química , Zircônio/química , Microscopia Eletrônica de Varredura , Cimentos de Resina/química
13.
J Adhes Dent ; 24(1): 445-457, 2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36562250

RESUMO

PURPOSE: To evaluate the efficacy of different surface treatments on the bond strength of polyetherketoneketone (PEKK) to ceramic materials. MATERIALS AND METHODS: PEKK test specimens were separated into four groups according to surface treatments (group S: sandblasting; group A: acid etching; group SA: sandblasting + acid etching; group C: control). Surface roughness values of PEKK specimens were measured before and after surface treatment. After the prepared PEKK specimens were bonded to lithium-disilicate glass-ceramic specimens with resin cement, they were kept in distilled water at 37°C for 24 h. Half of the specimens in each surface treatment group were thermocycled. All test specimens underwent shear bond strength testing. Failure modes were assessed using light microscopy and SEM. RESULTS: Statistical analysis demonstrated that surface treatments created significant roughness on the PEKK surfaces (p = 0.005). While group S showed the highest roughness values, group A showed the lowest. Of the thermocycled test groups, the sandblasting + acid etching group obtained the highest shear bond strengths. Among the non-thermocycled test groups, the sandblasting surface treatment group achieved the highest shear bond strengths. CONCLUSIONS: The application of surface treatments to enhance the bond strength of PEKK to ceramics has proven to be effective.


Assuntos
Colagem Dentária , Porcelana Dentária , Propriedades de Superfície , Porcelana Dentária/química , Cerâmica/química , Benzofenonas , Polímeros , Teste de Materiais , Cimentos de Resina/química , Resistência ao Cisalhamento , Análise do Estresse Dentário
14.
Odovtos (En línea) ; 24(3)dic. 2022.
Artigo em Inglês | LILACS-Express | LILACS, SaludCR | ID: biblio-1406161

RESUMO

Abstract Using a bur multiple times to prepare dental structure may produce a smoother final surface on dentin than a new one. This superficial roughness may affect adhesion with resin-based materials by modifying the substrates' characteristics. The aim of this study was to evaluate the effect of multiple uses of diamond burs on dentin's superficial microroughness and bond strength with resin composite when using a self-etch adhesive. Diamond dental burs were used to simulate a preparation (dentin flat surface) on extracted third molars. Samples were distributed into groups according to burs' number of previous uses as follows: 0, 1, 5 and 10. Scanning electron microscopy images at 70x, 350x, and 1000x were used to illustrate burs' deformation. Each specimen's dentin microroughness was measured three times to compare between experimental groups and the micro-shear bond strength test (n=15) was performed for the 0 and 10 uses groups using a universal adhesive in a self- etching mode. Diamond crystals wear and dislodgements were evident among groups where the burs were used more times. As the number of uses increased the mean microroughness of the dentin surface decreased with significant differences between the 0 and 10 uses groups. No statistical differences between experimental groups resulted from bond strength tests. When using a universal adhesive in a self-etching mode, the number of previous uses of a diamond bur seems to have no significant effect on dentin/resin composite bond strength.


Resumen El uso de una fresa múltiples veces para preparar la estructura dental puede producir una superficie final más lisa en la dentina que una fresa nueva. Esta rugosidad superficial modifica las características del sustrato y puede afectar la adhesión con materiales resinosos. El objetivo de este estudio fue evaluar el efecto de los múltiples usos de las fresas de diamante sobre la micro rugosidad superficial de la dentina y la resistencia adhesiva con la resina compuesta cuando se utiliza un adhesivo de autograbado. Se utilizaron fresas dentales de diamante para simular una preparación (superficie plana de la dentina) en terceros molares extraídos. Las muestras se distribuyeron en grupos según el número de usos previos de las fresas de la siguiente manera: 0, 1, 5 y 10. Se utilizaron imágenes de microscopía electrónica de barrido a ×70, ×350 y ×1000 para ilustrar la deformación de las fresas. Se midió la micro rugosidad de la dentina de cada espécimen tres veces para comparar entre los grupos experimentales y se realizó la prueba de resistencia a la adhesión por micro cizallamiento (n=15) para los grupos de 0 y 10 usos utilizando un adhesivo universal en modo de autograbado. El desgaste de los cristales de diamante y los desprendimientos fueron evidentes entre los grupos en los que las fresas se utilizaron más veces. A medida que aumentaba el número de usos, la micro rugosidad media de la superficie de la dentina disminuyó, con diferencias significativas entre los grupos de 0 y 10 usos. En las pruebas de resistencia adhesiva no se observaron diferencias estadísticas entre los grupos experimentales. Cuando se utiliza un adhesivo universal en modo de autograbado, el número de usos previos de una fresa de diamante no parece tener un efecto significativo en la resistencia de la unión dentina/resina del composite.


Assuntos
Humanos , Adesivos Dentinários/análise , Resistência ao Cisalhamento
15.
Odovtos (En línea) ; 24(3)dic. 2022.
Artigo em Inglês | LILACS-Express | LILACS, SaludCR | ID: biblio-1406159

RESUMO

Abstract: The purpose of this study was to compare the shear bond strength (SBS) of four resin-based composite materials to a silicate-based cement using a ''no-wait'' universal bond with self-etch (SE) and etch-and-rinse (ER) modes. Acrylic blocks (n=80, 2mm depth, 5mm diameter central hole) were prepared. The holes were filled with BiodentineTM (BD) and divided into 4 main groups (n=20) according to the composite resin type used: Group FZ250: FiltekTM Z250 Universal Restorative (microhybrid), Group SDR: SDR Plus U Bulk Fill Flowable (low-viscosity bulk-fill), Group FBP: FiltekTM Bulk Fill Posterior (high-viscosity bulk-fill), Group EF: EsFlow™ Universal Flowable Composite (nanohybrid). A 'no-wait' universal bond (Clearfil Universal Bond Quick) was used for bonding application. Then each group was divided into 2 subgroups according to the etching mode applied (ER and SE). SBSs were measured and stereomicroscope was used to identify the failure modes. Selected samples of fracture surfaces were imaged by SEM. Tukey's post-hoc and One-way ANOVA tests were used to analyze data. There were statistically significant differences among the composite groups (p 0.05). The SBS of BD to the resin composites depends on the composite type but application of the 'no-wait' universal bond in different etching modes is regardless of the SBS of BD to resin composites.


Resumen El objetivo de este estudio fue comparar la resistencia de adhesión al cizallamiento (SBS) de cuatro resinas con un cemento a base de silicato utilizando una adhesivo universal "no-wait" de autograbado (SE) y grabado y lavado (ER). Se prepararon bloques acrílicos (n=80, de 2mm de profundidad y un agujero central de 5mm de diámetro). Los agujeros se rellenaron con BiodentineTM (BD) y se dividieron en 4 grupos principales (n=20) según el tipo de resina compuesta utilizada: Grupo FZ250: FiltekTM Z250 Universal Restorative (microhíbrido), Grupo SDR: SDR Plus U Bulk Fill Flowable (bulk-fill de baja viscosidad), Grupo FBP: FiltekTM Bulk Fill Posterior (bulk-fill de alta viscosidad), Grupo EF: EsFlow™ Universal Flowable Composite (nanohíbrido). Para la aplicación de la adhesión se utilizó un adhesivo universal "no-wait" (Clearfil Universal Bond Quick). A continuación, cada grupo se dividió en 2 subgrupos según el modo de grabado aplicado (ER y SE). Se midieron los SBS y se utilizó el estereomicroscopio para identificar los modos de fallo. Las muestras seleccionadas de las superficies de fractura se analizaron mediante SEM. Se utilizaron las pruebas post-hoc de Tukey y ANOVA de una vía para analizar los datos. Hubo diferencias estadísticamente significativas entre los grupos de composites (p0,05). La SBS de la BD a los composites de resina depende del tipo de composite, pero la aplicación de la unión universal "no-wait" en los diferentes modos de grabado es independiente de la SBS de la BD a los composites de resina.


Assuntos
Humanos , Adesivos Dentinários , Resistência ao Cisalhamento , Turquia
16.
BMC Oral Health ; 22(1): 648, 2022 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-36578003

RESUMO

BACKGROUND: Adhesive tooth-colored restorations are strongly dependent on the substrate surface cleanliness to allow intimate contact between resin cement and dentin surface, so several methods were adopted for the total cleaning of temporary cement residues. This study aimed to assess the effect of mechanical and chemo-mechanical cleaning methods of temporary cement on the immediate shear bond strength of self-adhesive resin cement to dentin surface. METHODS: Forty freshly extracted lower first premolars were cut to expose a flat dentin surface. Discs of temporary crown composite resin material were constructed and cemented to the flat dentin surface using resin-based and non-eugenol temporary cement then stored at room temperature in distilled water. Dividing of samples into two groups according to the method of temporary cement cleaning. Group I (n = 20) mechanical cleaning using the rotary instrument, and group II (n = 20) chemo-mechanical cleaning using chlorhexidine-containing scrub. CAD/CAM reinforced Composite discs were bonded to the dentin surface using self-adhesive composite resin cement, then measurement of shear bond strength was done using a universal testing machine. Further analysis of failure mode after debonding was performed by Scanning electron microscope. RESULTS: No statistically significant difference was found between the mean shear bond strength of the two cleaning methods (P-value = 0.636). Regardless of the cleaning method, the group cemented with resin-based temporary cement showed statistically significantly higher mean shear bond strength than non-eugenol temporary cement (P-value = 0.048). CONCLUSION: Both cleaning methods (mechanical and chemo-mechanical) applied in this study were effective in cleaning temporary cement remnants from the dentin substrate surface with statistically significant differences between results of shear bond strength with significantly higher values recorded with resin-based temporary cement.


Assuntos
Colagem Dentária , Cimentos Dentários , Humanos , Cimentos Dentários/química , Cimentos de Resina/química , Cimento de Óxido de Zinco e Eugenol , Adesivos Dentinários/química , Cimentos de Ionômeros de Vidro , Resinas Compostas/química , Dentina , Teste de Materiais , Resistência ao Cisalhamento , Propriedades de Superfície , Análise do Estresse Dentário
17.
Med Sci Monit ; 28: e938867, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36540003

RESUMO

BACKGROUND This study aimed to compare the bond strength of orthodontic brackets onto the tooth enamel of 120 freshly extracted adult bovine medial lower incisors using 4 adhesives: a resin-modified glass ionomer adhesive, a composite adhesive, a liquid composite adhesive, and a one-step light-cured adhesive. MATERIAL AND METHODS The study group (120 freshly extracted bovine medial lower incisors) was divided into equal subgroups depending on the type of adhesive used to fix the brackets to the tooth enamel (n=30), and then according to the observation time (n=10). Orthodontic brackets were fixed onto the tooth enamel for 24 hours (T1), 3 months (T2), and 6 months (T3) using 4 types of adhesives: resin-modified glass ionomer adhesive Fuji Ortho LC, composite adhesive Transbond Plus Light Cure Band, flowable composite adhesive Transbond Supreme Low Viscosity, and a one-step light-cured adhesive GC Ortho Connect. Shear tests and fracture plane analyses were performed. RESULTS Statistically significant differences at time T1 were noted in the comparison of shear stress values when brackets were fixed with GC Ortho Connect adhesive compared to other adhesives (P<0.05), except for the Transbond Plus adhesive (P>0.05). At time T3, significant statistical differences occurred between GC Fuji Ortho LC and the other 3 adhesives (P<0.05). The fracture analysis showed that, regardless of the time function, adhesive-cohesive fractures without damage to the enamel were the most common for all the assessed materials. CONCLUSIONS Of the adhesives evaluated, GC Ortho Connect appears to be the most appropriate choice for bonding orthodontic brackets to the enamel surface.


Assuntos
Colagem Dentária , Braquetes Ortodônticos , Bovinos , Animais , Adesivos/química , Incisivo , Cimentos de Ionômeros de Vidro , Cimentos de Resina/química , Teste de Materiais , Esmalte Dentário , Resistência ao Cisalhamento
18.
BMC Oral Health ; 22(1): 644, 2022 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-36572875

RESUMO

AIM: This study aimed to evaluate the effect of using whitening dentifrices during at-home bleaching on the shear bond strength (SBS) of resin composite to dentin, and investigate whether the increased polymerization time would improve SBS. METHODS: Ninety-six bovine incisors were divided into 4 groups of 24, according to the whitening treatment applied as follows: group 1, at-home bleaching + brushing with a regular dentifrice; group 2, at-home bleaching + brushing with a whitening dentifrice containing ozone; group 3, at-home bleaching + brushing with a commercial whitening dentifrice; and group 4 (control), no whitening/brushing treatment. Each group was divided into two subgroups (n = 12) to assess the effect of curing time (20 versus 80 s) on SBS. A self-etch adhesive was bonded to dentin, and after 2-day water storage, SBS was determined. RESULTS: SBS was significantly affected by the whitening treatment (P = 0.03), but increasing the curing time had no significant effect on SBS (P = 0.137). Bond strength in group 1 was comparable to the control group (P > 0.05). The specimens in group 3 displayed significantly lower SBS than either group 4 or group 1 (P > 0.05). No significant difference was observed between the SBS of group 2 compared to any other group (P > 0.05). There was no significant association between the treatment group and failure type (P > 0.05). CONCLUSION: The bonding interface was not negatively influenced by the at-home bleaching procedure. However, using a commercial whitening dentifrice during at-home bleaching produced a significant detrimental effect on SBS. Extending the curing time would have no beneficial effect on adhesion to a whitened dental substrate.


Assuntos
Colagem Dentária , Dentifrícios , Humanos , Animais , Bovinos , Dentifrícios/uso terapêutico , Cimentos Dentários , Resinas Compostas/uso terapêutico , Resinas Compostas/química , Dentina , Resistência ao Cisalhamento , Teste de Materiais , Cimentos de Resina/uso terapêutico , Análise do Estresse Dentário
19.
Braz. j. oral sci ; 21: e226952, jan.-dez. 2022. ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1393283

RESUMO

Aims: To verify the efficacy of Er,Cr:YSGG laser for debonding of lithium disilicate (LD) reinforced glass ceramic veneers of different thicknesses. Methods: Forty bovine teeth were prepared and randomly divided into four groups (n=10/group) according to the ceramic disc thickness: C0.5 (Control group) and L0.5 (Laser irradiated group) in which LD discs had a thickness of 0.5mm and 5mm diameter; C1 and L1 in which LD discs had a thickness of 1mm and 5mm diameter. The lithium disilcate discs (IPS E.max®, shade HTA2) were fabricated following the manufacturer's recommendations and cemented to the prepared tooth surface. The Er,Cr:YSGG laser was applied to the laser groups at 2.5W and 25Hz for 60seconds. Universal testing machine was used to evaluate the shear bond strength for all samples at a cross head speed of 1mm/min in an inciso-gingival direction parallel to the sample surface. After debonding, the samples were examined under stereoscope to evaluate the mode of failure according to the adhesive remnant index (ARI). Results: Laser irradiation significantly diminishes the shear bond strength from 10.868 MPa to 3.778 MPa for C0.5 and L0.5 groups respectively (p=0.00) and from 14.711 MPa to 4.992 MPa for C1 and L1 groups respectively (p=0.00). The shear bond strength required for debonding increased with increasing thickness of discs, but without significant difference (p=0.110). Higher ARI scores were seen in the laser groups (more cement remaining adhered to the tooth) when compared to the control groups. Conclusions: The Er,Cr:YSGG laser could be an effective and useful tool in debonding of lithium disilicate ceramic veneers as it decreases the shear bond strength required for veneer debonding


Assuntos
Cerâmica , Resistência ao Cisalhamento , Facetas Dentárias , Lasers
20.
Dent Mater ; 38(12): 1942-1946, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36347654

RESUMO

OBJECTIVES: The aim was to investigate shear bond strengths and failure modes of four self-etch bonding agents to bovine dentin and enamel and to compare evaluation of data sets with or without exclusion of cohesive failure specimens. METHODS: Composite-cylinders were bonded perpendicularly to bovine dentin and enamel surfaces. Shear-strengths were measured 24 h post-bonding of: Scotchbond Universal® (SBU, 3 M), OptiBond™ XTR (OBXTR, Kerr), OptiBond™ universal (OBU, KaVo-Kerr) and Prime & Bond active® (PBA, Dentsply-Sirona). Analysis of overall data was made via a linear mixed-model. This was repeated after exclusion of specimens associated with cohesive failures. RESULTS: When both adhesive and cohesive failures were considered, OBU and OBXTR showed comparable dentin and enamel bond strengths, whereas lower strengths were found on enamel for SBU (p < 0.001) and PBA (p = 0.015). For OBXTR higher shear strengths were measured for specimens associated with cohesive failures. When cohesive failures were excluded, the majority of shear bond strengths of adhesive failure specimens were only slightly different from overall results. However, uniquely with OBXTR dramatically lower shear bond strengths were found for dentin substrate. SIGNIFICANCE: After exclusion of cases with cohesive failures OBXTR adhesive fell behind other materials in the sequence of average shear strengths. This did not reflect the actual performance of the material. Therefore, in statistical analysis we do not recommend exclusion of data based on a specific fracture mode.


Assuntos
Colagem Dentária , Adesivos Dentinários , Bovinos , Animais , Adesivos Dentinários/química , Colagem Dentária/métodos , Dentina/química , Cimentos Dentários/química , Teste de Materiais , Cimentos de Resina/química , Resistência ao Cisalhamento , Resinas Compostas/química
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