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1.
Artigo em Inglês | MEDLINE | ID: mdl-32233200

RESUMO

The purpose of the present study was to (1) investigate the micro-shear bond strength and failure mode of a novel methacryloxydecyl-dihydrogen-phosphate (MDP) calcium-fluoride-releasing self-adhesive resin cement (TheraCem, BISCO) to a tooth structure (enamel and dentin) and to yttrium-stabilized zirconia after thermocycling, and to (2) compare the results with a universal non-MDP-containing self-adhesive resin cement (RelyX Unicem, 3M ESPE) as a control. Enamel and dentin specimens (20 discs each) were obtained by using a diamond saw (IsoMet 4000, Buehler) with copious water coolant. Twenty zirconia plates were obtained from IPS e.max ZirCAD blocks (Ivoclar Vivadent) and sintered in an inFire HTC speed high-temperature furnace (Dentsply Sirona). Resin-cement micro-cylinders were created on the bonded surface and filled with the tested cements (n = 10 for each surface/cement combination): Group A (control) used non-MDP-containing RelyX, whilegroup B (tested cement) used MDP-containing TheraCem MDP. Cements were left to self-cure for 5 minutes. All specimens were thermocycled for 5,000 cycles (THE-1100, SD Mechatronik). Micro-shear bond strength was measured using a universal testing machine, and debonded surfaces were examined for failure mode analysis with all morphologic and ultrastructure changes using a scanning electron microscope (Quanta 250 Field Emission Gun, FEI) attached with an energy dispersive x-ray (EDX) unit. The results were statistically analyzed. TheraCem had a slightly higher micro-shear bond strength (MPa) value than RelyX. Within enamel, TheraCem (6.46 ± 1.37 MPa) had a significantly higher mean µ-SBS value than RelyX (3.04 ± 0.99 MPa) (P = .002). Similarly, TheraCem in dentin (10.67 ± 1.27 MPa) had a significantly higher mean value than RelyX (6.46 ± 1.74 MPa) (P = .014). As for zirconia, TheraCem (39.76 ± 1.18 MPa) had a significantly higher mean µ-SBS value than RelyX (27.04 ± 1.92 MPa) (P < .001). Using MDP-containing calcium-fluoride-releasing self-adhesive resin cement (TheraCem) may improve bond strength to all tested substrates (enamel, dentin, and zirconia) and can be considered a promising cement for many clinicians. Further clinical studies are required to provide long-term clinical success data.


Assuntos
Colagem Dentária , Cimentos de Resina , Cálcio , Fluoreto de Cálcio , Cimentos Dentários , Análise do Estresse Dentário , Fluoretos , Teste de Materiais , Resistência ao Cisalhamento , Propriedades de Superfície , Zircônio
2.
J Indian Soc Pedod Prev Dent ; 38(1): 2-7, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32174622

RESUMO

Background: Stainless steel crowns (SSCs) are unique coronal restorative materials used commonly in the management of primary teeth with extensive caries. Aim: The aim of this study was to perform a systematic review to evaluate the retentive strength of luting cements for SSCs. Materials and Methods: Two reviewers performed a database search of the studies published from 2004 till date. The inclusion criteria were papers published in the English language andin vitro studies on retentive strength of SSC on primary molars. All potentially relevant studies were identified by the title and the abstract. After the full-text analysis, the selected studies were included in the systematic review. Results: Sixteen nonduplicated studies were found. However, after reviewing the articles, only seven were included. Risk bias was assessed. Out of seven studies included in the systematic review, five studies presented medium risk of bias and two studies showed high risk of bias. Conclusion: Within the limitations of this study, thein vitro literature seems to suggest that the use of self-adhesive resin cements shows higher retentive strength, followed by resin-modified glass-ionomer cement (RM-GIC) and conventional GIC. However, RM-GIC can be a preferred luting agent due to its clinical advantages over resin cements. Thus, it can be concluded that choice of cement will depend on individual patient needs and clinical situation.


Assuntos
Coroas , Retenção em Prótese Dentária , Aço Inoxidável , Cimentação , Cimentos Dentários , Cimentos de Ionômeros de Vidro , Humanos , Teste de Materiais , Cimentos de Resina
3.
Braz Oral Res ; 34: e018, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32187304

RESUMO

The objective of this study was to evaluate the influence of hydrofluoric acid (HF) concentration, etching time, and application of phosphoric acid (PA) followed by neutralization with sodium bicarbonate on the bond strength between a feldspar ceramic and resin cement. Thus, 80 blocks (10 x 12 x 2 mm) of glass ceramic (VM - Vita Mark II - Vita Zahnfabrik) were made and randomly assigned to eight groups (n = 10) according to the factors: HF concentration (5 and 10%), etching time (60 and 120 s), and use of phosphoric acid (PA) (with and without). According to the experimental group, 37% PA (Condac, FGM) was applied after HF etching for 60s. Afterwards, samples were immersed in sodium bicarbonate for 1 min then in an ultrasonic bath in distilled water (5 min) for cleaning. After surface bonding treatment, cylinders (Ø = 2 mm; h = 2 mm) of dual resin cement (AllCem / FGM) were made in the center of each block. The samples were then stored in water (37ºC) for 90 days and submitted to the shear bond test (50 KgF, 1 mm/min). Failure analysis was performed by stereomicroscope and scanning electron microscopy. Data (MPa) were analyzed with 3-way ANOVA and Tukey's test. Only the factor "HF concentration" was significant (p = 0.02). Most failures were of cohesive in ceramic (40%) and mixed types (42.5%). The 10% HF resulted in higher shear bond strength value than the 5% HF. Surface cleaning with phosphoric acid followed by sodium bicarbonate and HF time (60 or 120 seconds) did not influence the resin bond strength to feldspar ceramic.


Assuntos
Silicatos de Alumínio/química , Colagem Dentária/métodos , Ácido Fluorídrico/química , Ácidos Fosfóricos/química , Compostos de Potássio/química , Análise de Variância , Porcelana Dentária/química , Teste de Materiais , Metacrilatos/química , Microscopia Eletrônica de Varredura , Valores de Referência , Reprodutibilidade dos Testes , Cimentos de Resina/química , Resistência ao Cisalhamento/efeitos dos fármacos , Silanos/química , Propriedades de Superfície , Fatores de Tempo
4.
Braz Dent J ; 31(1): 52-56, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32159706

RESUMO

The present study was evaluated the effect of different light activation and thermocycling methods on the shear bond strength (SBS) and on the adhesive remnant index (ARI) of metal brackets bonded to feldspathic ceramic. Hundred metal brackets were bonded to 20 porcelain cylinders, divided into four groups (n=25) based on light activation and thermocycling processes. The cylinders were etched with 10% hydrofluoric acid for 60 s and coated with two layers of silane. The brackets were bonded with Transbond XT composite resin. Light activation in Groups 1 and 3 was performed during 3 s using the VALO Ortho Cordless appliance with irradiance 3,200 mW/cm2 and in Groups 2 and 4 for 40 s using Optilight Max appliance with irradiance 1,200 mW/cm². The samples were stored in deionized water at 37°C for 24 h and the samples from Groups 1 and 2 were submitted to the SBS test at a rate of 1 mm/min, whereas the samples from Groups 3 and 4 were submitted to 7,000 thermal cycles (5°/55°C) before to the SBS test. The data were assessed by two-way analysis of variance and by Tukey's test (a=0.05). No significant difference was observed between SBS means in the different light activation devices used. The samples subjected to thermocycling revealed lower SBS values (p≤0.05). There was predominance of score 0 for ARI in all groups. Therefore, the different light activation methods did not interfere in SBS, but thermocycling reduced SBS.


Assuntos
Colagem Dentária , Braquetes Ortodônticos , Cimentos Dentários , Porcelana Dentária , Análise do Estresse Dentário , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento , Propriedades de Superfície
5.
Braz Dent J ; 31(1): 69-77, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32159709

RESUMO

The objective was to evaluate the color stability of ceramic veneers luted with resin cements and pre-heated composite resins (60oC) for 12 months, and determine the degree of conversion (DC) of the luting agents. Two resin cements (AllCem Veneer, light-cured (LRC) and AllCem, dual-cured (DRC)] and three composite resins [Z100 (MNCR-minifilled), Herculite Classic (MHCR-micro-hybrid) and Durafill (MCCR-microfilled)] were used for cementing 0.8-mm-thick lithium-silicate glass-ceramic laminates (Suprinity, shade B2-HT, Vita) on bovine enamel (n=10). The specimens were stored at 37oC in distilled water. CIELab parameters were determined at 24h after luting (baseline), 7, 30, 90, 180 days and 12 months. Three specimens were prepared for DC evaluation, performed by micro-Raman spectroscopy. Data were analyzed by ANOVA and Tukey's test (a=5%). For ΔEab and ΔE00, there were significant differences for luting material (p<0.001), time (p<0.001), and double interaction (p<0.001). The groups cemented with MHCR (1 year), MCCR (90 days and 1 year) and MCCR-PH (1 year) were the ones with ΔE values greater than the acceptability threshold. All other groups maintained their ΔE lower than the acceptability threshold after 1 year in distilled water. Regarding DC, there were no significant differences (p=0.127) among the materials. Non-significant negative correlations were observed between the mean ΔEab and DC (R=-0.65) and ΔE00 and DC (R=-0.64). A significant positive correlation was observed mean ΔEab and ΔE00 (R=0.99). It was concluded that the different luting agents influenced the final color of the restorations. The heating of the composite resins did not affect their DC.


Assuntos
Cerâmica , Cimentos de Resina , Animais , Bovinos , Cor , Resinas Compostas , Porcelana Dentária , Facetas Dentárias , Seguimentos , Teste de Materiais
6.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 55(2): 135-138, 2020 Feb 09.
Artigo em Chinês | MEDLINE | ID: mdl-32074678

RESUMO

Establishing a stable resin-dentin hybrid layer is an effective method to improve the adhesion durability of the restoration. The biomodification of dentin by cross-linkers can enhance the mechanical properties of collagen and resistance to enzymatic hydrolysis while, inhibiting the process of demineralization and promoting the remineralization of dentin, which has the potential clinical applicability of preventing dental caries and improving adhesive property. This review summarizes the biomodification of dentin type Ⅰ collagen by different cross-linkers.


Assuntos
Colágeno Tipo I/química , Colagem Dentária , Adesivos Dentinários , Dentina/química , Cárie Dentária/prevenção & controle , Humanos , Teste de Materiais , Cimentos de Resina
7.
J Appl Oral Sci ; 28: e20190371, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32049135

RESUMO

OBJECTIVE: This study aims to evaluate the influence of different air-abrasion pressures and subsequent heat treatment on the flexural strength, surface roughness, and crystallographic phases of highly translucent partially stabilized zirconia (Y-PSZ), and on the tensile bond strength of resin cement to Y-PSZ. METHODOLOGY: Fully sintered zirconia specimens were ground with SiC paper (control) and/or air-abraded with 50 µm particles of alumina at 0.1, 0.15, 0.2, or 0.3 MPa or left as-sintered. After air-abrasion at 0.2 MPa (0.2AB), additional specimens were then heated to 1500°C, and held for one hour at this temperature (0.2AB+HT1h). Flexural strength and surface roughness were evaluated. Crystalline phase identification was also carried out using X-ray diffraction. Bonded zirconia specimens with self-adhesive resin cement were stored in distilled water at 37°C for 24 h, either with or without aging (thermal cycling 4-60°C/20000). Results were analyzed statistically by ANOVA and Tukey-Kramer tests. RESULTS: The flexural strength decreased with the increase in air-abrasion pressure, while in contrast, the surface roughness increased. The lowest flexural strength and the highest roughness value were found for the 0.2AB and 0.3AB groups, respectively. All groups contained cubic-, tetragonal ( t )-, and rhombohedral ( r )-ZrO2 phases with the exception of the as-sintered group. Upon increasing the air-abrasion pressure, the relative amount of the r -ZrO2 phase increased, with a significant amount of r -ZrO2 phase being detected for the 0.2AB and 0.3AB groups. The 0.2AB+HT1h group exhibited a similar flexural strength and t -ZrO2 phase content as the as-sintered group. However, the 0.2AB group showed a significantly higher tensile bond strength (p<0.05) than the 0.2AB+HT1h group before and after aging. CONCLUSION: Micromechanical retention by alumina air-abrasion at 0.2 MPa, in combination with chemical bonding of a resin to highly translucent Y-PSZ using a MDP-containing resin cement may enable durable bonding.


Assuntos
Abrasão Dental por Ar/métodos , Óxido de Alumínio/química , Colagem Dentária/métodos , Cimentos de Resina/química , Zircônio/química , Análise de Variância , Resistência à Flexão , Temperatura Alta , Teste de Materiais , Microscopia Confocal/métodos , Valores de Referência , Reprodutibilidade dos Testes , Propriedades de Superfície , Resistência à Tração , Difração de Raios X/métodos
8.
J Adhes Dent ; 22(1): 7-34, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32030373

RESUMO

This literature-based OPINION PAPER reflects in an introductory historical perspective on the rapid advancement of dental adhesive technology. Past and current techniques to bond to tooth tissue, in particular to dentin as the most challenging bonding substrate, are critically appraised. Including the historical perspective in (1), this paper focuses on fourteen items thought to be of primary importance with regard to the current status of dental adhesive technology. In (2) the primary mechanisms involved in adhesion to enamel and especially dentin are dealt with having (3) also revisited the previously introduced adhesion-decalcification concept (AD concept) as basis of biomaterial-hard tissue interaction; the worldwide accepted classification of today's adhesives into etch&rinse (E&R) and self-etch (SE) adhesives are presented in (4), along with presentation of their respective PLUS-MINUS balances in (5) and (6); nomination of the GOLD-STANDARD E&R (7) and SE (8) adhesives is based on evidence of successful laboratory and long-term clinical performance, resulting in a recommended 3-step full E&R bonding route in (9) and the preferred 3-step combined selective enamel E&R with 2-SE bonding route in (10); (11) description of the main bond-degradation pathways and eight strategies to preserve bond stability; (12) coverage of the PROS and CONS of the newest generation of UNIVERSAL adhesives. Looking into the future, some expected future developments in dental adhesive technology have been suggested in (13), along with (14) a first status determination of the latest research-and-development towards self-adhesive restorative materials that no longer require any pre-treatment.


Assuntos
Colagem Dentária , Cimentos Dentários , Dentina , Adesivos Dentinários , Teste de Materiais , Cimentos de Resina
9.
J Adhes Dent ; 22(1): 47-58, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32030375

RESUMO

PURPOSE: The development of a novel material requires a comprehensive pre-clinical assessment of clinical longevity before any market release. This study aimed to investigate the mechanical performance of a novel self-adhesive restorative material (ASAR MP4). MATERIALS AND METHODS: Fracture strength (FS), flexural fatigue strength (FFS) and fracture toughness (KIc) were measured for the experimental material ASAR MP4 in self-cure (SC) and light-cure (LC) mode. ASAR MP4 was processed in capsules. Three direct resin composites (CeramX mono+, DentsplySirona; Heliomolar, IvoclarVivadent; Filtek Supreme XTE, 3M) and two glass-ionomer-cement (GIC) based materials (Equia Forte, GC; Fuji II LC, GC) were selected for comparison with ASAR MP4. FS specimens (n = 15) were tested in a 4-point bending configuration according to ISO 4049 and 9917. FFS specimens (n = 25) were additionally stressed for 104 loading cycles using the staircase approach. The single-edge-notch beam (SENB) configuration was selected for determining KIc according to ISO 13586. All specimens were stored for 14 days at 37°C. Data were analyzed using Weibull statistics (FS), ANOVA (FS, KIc), and the non-parametric Mann-Whitney U-test (FFS). RESULTS: The FS, FFS and KIc data of the ASAR MP4 material reveal a mechanical performance in the range of the successful permanent direct resin composites CeramX mono+ and Heliomolar. The results for ASAR MP4 in SC mode were superior to the LC mode. A fine-grained and pore-free microstructure was observed. CONCLUSION: Within the limitations of this study we conclude that the novel self-adhesive restorative material ASAR MP4 exhibits mechanical performance close to that of the resin composites Heliomolar and CeramX mono+, both indicated for permanent use in the load-bearing posterior region. Processing the material in either self-cure or light-cure mode led to superior performance over glass-ionomer cements.


Assuntos
Resinas Compostas , Cimentos Dentários , Materiais Dentários , Cimentos de Ionômeros de Vidro , Teste de Materiais , Cimentos de Resina
10.
J Adhes Dent ; 22(1): 65-77, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32030377

RESUMO

PURPOSE: This study investigated the bonding efficacy of a new so-called self-adhesive composite hybrid onto flat (FLAT) and high C-factor class-I cavity-bottom (CAVITY) dentin. MATERIALS AND METHODS: The immediate and aged (50,000 thermocycles) microtensile bond strength (µTBS) to FLAT and CAVITY dentin of the experimental self-adhesive bulk-fill restorative (K-0180 ASAR pilot [ASAR-pilot], Dentsply Sirona) was compared to that of two universal adhesives applied in self-etch mode and combined with a bulk-fill composite (Prime&Bond Elect/QuiXfil [P&Be/QuiXF], Prime&Bond Active/QuiXfil [P&Ba/QuiXF], both Dentsply Sirona), two pre-conditioned materials (Activa Bioactive-Restorative [Activa], Pulpdent; Fuji II LC Improved [Fuji2LC], GC); and one bulk-fill glass-hybrid restorative (Equia Forte Fil [EquiaF], GC). Statistically significant differences were recorded using Welch's ANOVA with Games-Howell contrast (p < 0.05). RESULTS: No significant difference in immediate µTBS was recorded when the restorative materials were applied onto FLAT dentin, except for Activa_FLAT and EquiaF_FLAT. When bonded to CAVITY dentin, the significantly highest µTBS was recorded for Fuji2LC_CAVITY (layer filled), and was not significantly different only from P&Ba/QuiXF_CAVITY. Upon aging, the highest µTBS to flat dentin was achieved by ASAR-pilot_FLAT, which was not significantly different from P&Be/QuiXF_FLAT and Fuji2LC_FLAT. No significant difference between immediate and aged µTBS was recorded for ASAR-pilot when bonded onto FLAT or CAVITY dentin; the latter, however, was associated with low bond strength. CONCLUSION: Favorable bonding performance was found for the new self-adhesive bulk-fill composite hybrid ASAR-pilot when bonded to flat dentin. However, much lower bond strength was recorded when ASAR-pilot was bonded to high C-factor cavity-bottom dentin.


Assuntos
Colagem Dentária , Adesivos Dentinários , Resinas Compostas , Cimentos Dentários , Dentina , Teste de Materiais , Cimentos de Resina , Resistência à Tração
11.
J Adhes Dent ; 22(1): 79-84, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32030378

RESUMO

PURPOSE: To use shear bond strength (SBS) testing to determine the effect of surface moisture and smear layer thickness on the adhesion of self-adhesive restorative materials and a universal adhesive. MATERIALS AND METHODS: One single-step self-etch universal adhesive, Prime & Bond Active (PA), was used to bond Ceram.x Spectra ST HV composite resin to dentin and enamel using the self-etching technique. Three commercially available restorative materials and one newly developed material with self-adhesive properties, Activa (A), Fuji II LC(F), Equia Forte (E), and ASAR-MP4 (S), respectively, were also bonded to enamel and dentin prepared moist and dry and to dentin prepared with a thick smear layer. Shear bond testing was performed using an Ultradent bonding apparatus. RESULTS: The universal adhesive generated the highest SBS to dentin and enamel, followed by the newly developed material. None of the materials tested were significantly affected by the moisture conditions on enamel or dentin. The thickness of smear layer significantly affected SBS to dentin for S, F, and E. However, S and F still exhibited higher shear bond strength to dentin with the thicker smear layer compared to the other self-adhesive materials. Only the universal adhesive in self-etch mode was not affected by the thicker smear layer and maintained significantly higher SBS. CONCLUSION: None of the materials tested were affected by bonding to overdried dentin or enamel. All of the self-adhesive materials exhibited lower SBS to specimens with a thicker smear layer. The newly developed material ASAR-MP4 compared favorably to the other self-adhesive materials tested under all test conditions.


Assuntos
Colagem Dentária , Camada de Esfregaço , Cimentos Dentários , Dentina , Adesivos Dentinários , Dessecação , Humanos , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento
12.
J Adhes Dent ; 22(1): 85-97, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32030379

RESUMO

PURPOSE: The material structure and chemical elemental composition of a new self-adhesive composite hybrid were investigated. The bonding performance when applied on flat (FLAT) vs high C-factor class-I cavity-bottom (CAVITY) dentin and in light-cure (LC) vs self-cure (SC) mode was determined. MATERIALS AND METHODS: The self-adhesive bulk-fill composite Surefil One (Su-O; Dentsply Sirona) was compared with the resin-modified glass-ionomer Fuji II LC Improved (Fuji2LC; GC) and the ion-releasing alkasite material Cention N (CentionN; Ivoclar Vivadent). The material structure was examined with SEM and TEM, while the chemical elemental composition was analyzed using EDS. The immediate and aged microtensile bond strength (µTBS) of Su-O_LC/SC was compared to that of Fuji2LC applied without any pre-treatment, and to that of CentionN applied following bonding with Adhese Universal (AU) (Ivoclar Vivadent) in self-etch mode (AU/CentionN). All restorative materials were bonded onto FLAT and CAVITY dentin. Statistical analysis was performed with the Kruskal-Wallis nonparametric test. RESULTS: EDS analysis revealed that Su-O was richer in C and P than the reference restorative materials. Applied to FLAT dentin, the significantly highest immediate and aged µTBS were recorded for AU/CentionN, which were not significantly different only from Su-O_LC. Applied to CAVITY dentin, the significantly highest immediate µTBS was recorded for AU/CentionN, which did not differ significantly only from Su-O_SC. Su-O_LC bonded to CAVITY dentin suffered from a high incidence of pre-test failures. CONCLUSION: While Su-O_LC bonded effectively and durably to FLAT dentin, Su-O_SC bonded more favorably than Su-O_LC in class-I cavities, which was probably related to shrinkage stress variously challenging the respective bond.


Assuntos
Colagem Dentária , Adesivos Dentinários , Resinas Compostas , Cimentos Dentários , Dentina , Teste de Materiais , Cimentos de Resina , Resistência à Tração
13.
J Adhes Dent ; 22(1): 99-105, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32030380

RESUMO

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.


Assuntos
Colagem Dentária , Adesivos Dentinários , Ataque Ácido Dentário , Cimentos Dentários , Esmalte Dentário , Análise do Estresse Dentário , Dentina , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento
14.
J Adhes Dent ; 22(1): 107-116, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32030381

RESUMO

PURPOSE: This in vitro study evaluated marginal integrity, 2-body wear, and fracture behavior of an array of bonded and nonbonded posterior restorative materials after thermomechanical loading (TML). MATERIALS AND METHODS: Eighty-eight MOD cavities with one proximal box beneath the CEJ were prepared in extracted human third molars according to a well-established protocol. Direct restorations were made using the following materials: amalgam (Dispersalloy), Ketac Molar Quick, Surefil One (with or without light curing), Activa, AdheSE Universal/Heliomolar, Fuji II LC improved, Equia Forte, Scotchbond Universal/Filtek Supreme, Xeno V+/CeramX.mono+, Prime&Bond active/Spectra ST CeramX HV, Prime&Bond elect/Spectra ST CeramX HV. Before and after thermomechanical loading (2500/5000/12,500 thermocycles between 5°C and 55°C + 100,000/ 200,000/500,000 x 50 N), marginal gaps and 2-body wear depths were analyzed on epoxy resin replicas using SEM and CLSM. Fractures were observed under a light microscope (20X). Results were analyzed with Kruskal-Wallis and Mann-Whitney U-tests (p < 0.05). RESULTS: For marginal quality, Surefil One showed promising in vitro behavior close to that of resin composite bonded with a self-etch adhesive (p > 0.05). For wear, amalgam and resin composites with recent filler technology were still superior (p < 0.05), but Surefil One LC outperformed Activa, Ketac Molar Quick, Equia Forte Fil, and Fuji II LC (p < 0.05). When Surefil One was occlusally light cured, no fractures occured, even after 500,000 cycles of TML. CONCLUSION: The novel self-adhesive posterior restorative Surefil One did not exhibit superior outcomes for all evaluated aspects. However, it showed stable fracture behavior, good marginal quality, and acceptable wear resistance in vitro.


Assuntos
Adaptação Marginal Dentária , Restauração Dentária Permanente , Resinas Compostas , Materiais Dentários , Cimentos de Ionômeros de Vidro , Humanos , Teste de Materiais , Cimentos de Resina
15.
Braz Oral Res ; 34: e001, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32022221

RESUMO

This study analyzed the effect of prior application of copaiba oil (CO) emulsions as a dentin cleaning substance on microleakage and microtensile adhesive strength. Twenty-five premolars and sixty-four molars were used for microleakage and microtensile assays. For the microleakage assays, specimens with standard class V cavities were divided (n = 5), according to the tested CO emulsions: CO10%X, CO10%Y, and CO10%Z, as well as chlorhexidine 2% (CHX) and distilled water (DW), as positive and negative controls, respectively. Restorations were performed using the Adper Single Bond® and/or Clearfil SE Bond® systems. Cervical, occlusal, distal and mesial sections were assessed for tracer penetration degree at the composite/tooth interface. For the microtensile assay, healthy molars were divided into sixteen groups, in which artificial caries were induced in half of the groups. Dentin surfaces were treated with CO10%X and CO10%Y, CHX and DW. Microtensile bond strength was measured by fixing each sample to the plate of a universal testing machine operated at a speed of 0.5 mm/minute until failure. Dentin treated with CO10%X showed a lower infiltration rate than dentin treated with the other CO emulsions, CHX2% and DW. According to the microtensile assay, both healthy and affected dentin treated with CO10%X and Adper Single Bond® adhesive system presented higher adhesive strength. CO emulsion, used as a dentin biomodifier, interfered positively in microleakage and improved adhesive strength after acid etching in the Adper Single Bond® adhesive system, or before applying the Clearfil SE Bond® self-etching system.


Assuntos
Colagem Dentária/métodos , Adesivos Dentinários/química , Dentina/efeitos dos fármacos , Fabaceae/química , Óleos Vegetais/química , Análise de Variância , Clorexidina/química , Resinas Compostas/química , Cimentos Dentários/química , Infiltração Dentária , Dentina/química , Emulsões/química , Humanos , Teste de Materiais , Reprodutibilidade dos Testes , Cimentos de Resina/química , Estatísticas não Paramétricas , Propriedades de Superfície , Resistência à Tração
16.
Braz Oral Res ; 34: e004, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32022223

RESUMO

The aim of this study was to analyze the structural, morphological and mechanical properties of two different lithium disilicate glass-reinforced ceramics for CAD-CAM systems (IPS e.max CAD and Rosetta SM). Five methodologies were used for both ceramics: microstructure (n = 2) was analyzed using x-ray diffraction (XRD); morphological properties (n = 2) were analyzed by scanning electron microscopy (SEM), with and without hydrofluoric etching; porosity (n = 3) was assessed using 3D micro-computed tomography (micro-CT); flexural strength was measured (n =1 0) using the three-point bending test; and bond strength was determined with self-adhesive resin cement (n = 10), using a microshear bond test. After performing all the tests, the data were analyzed using t-Student test and two-way ANOVA. All the tests used a significance level of α = 0.05. High peak positions corresponding to standard lithium metasilicate and lithium disilicate with similar intensities were observed for both ceramics in the XRD analysis. Morphological analysis showed that the crystalline structure of the two ceramics studied showed no statistical difference after acid etching. Additionally, no significant differences were recorded in the number or size of the pores for the ceramics evaluated. Moreover, no differences in flexural strength were found for the ceramic materials tested, or in the bond strength to ceramic substrates for the resin cements. Based on the study results, no significant differences were found between the two CAD-CAM lithium disilicate glass-reinforced ceramics tested, since they presented similar crystalline structures with comparable intensities, and similar total porosity, flexural strength and bond strength.


Assuntos
Cerâmica/química , Projeto Auxiliado por Computador , Porcelana Dentária/química , Vidro/química , Análise de Variância , Colagem Dentária/métodos , Resistência à Flexão , Teste de Materiais , Microscopia Eletrônica de Varredura , Porosidade , Valores de Referência , Reprodutibilidade dos Testes , Cimentos de Resina/química , Resistência ao Cisalhamento , Propriedades de Superfície , Difração de Raios X
17.
Int J Prosthodont ; 33(2): 202-211, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32069345

RESUMO

PURPOSE: To evaluate the amount of residual cement (ECL) around the margins of zirconia crown copings after careful luting and cleaning procedures and to investigate these factors in relation to two tested luting materials. MATERIALS AND METHODS: An experimental model of a maxillary arch was selected for this in vitro study. The maxillary first molar was prepared to receive an all-ceramic, single, full-crown restoration with a finish line located 1 mm below the artificial gingiva. After scanning of the prepared tooth, 20 paired zirconia coping-abutment assemblies were CAD/CAM fabricated. A slot in the model allowed for insertion and removal of the assemblies for each new test. Specimens were divided into two groups according to the cementation procedure: half (n = 10) were luted using a resin-modified glass-ionomer (RMGI) (Ketac-Cem Plus) (GI group), and the other half with a dual-curing self-adhesive resin agent (RelyX Unicem 2) (UN group). The substructures were loaded with cement, and a customized preseating device was adopted for preliminary reduction of excess. The zirconia copings were finally seated on their respective abutments located on the simulation model. A blinded investigator attempted to remove all excess cement with clinically available instruments. The amount of excess cement left in situ after cleaning procedures was weighed in grams. Dislodging forces of luted coping-abutment assemblies were obtained by using pull-off tests in a universal testing machine (crosshead speed of 0.5 mm/minute) after 24 hours of water storage. Means and standard deviations were calculated for ECL and for retention force values, and Mann-Whitney and ANOVA tests were carried out to detect significant differences (α = .05) among groups. RESULTS: Cement remnants were found in all specimens despite the cleaning procedures, with a typical distribution in interproximal areas. Mean ECL values for the GI and UN groups were 0.0079 ± 0.0060 and 0.0107 ± 0.0081, respectively. No statistically significant differences were found between tested cements (P = .3284). Removal stress values (MPa) were significantly higher (P = .0313) for the UN group (12.4 ± 6.5) than for the GI group (6.57 ± 4.69). CONCLUSION: Similar amounts of undetected cement remnants were discovered around the esthetic margins of zirconia crown copings regardless of cement type. The luting procedure using the self-adhesive resin cement provided significantly higher early retention values than the RMGI material.


Assuntos
Cimentos Dentários , Retenção em Prótese Dentária , Adaptação Psicológica , Cimentação , Coroas , Análise do Estresse Dentário , Estética Dentária , Cimentos de Ionômeros de Vidro , Teste de Materiais , Cimentos de Resina , Propriedades de Superfície , Zircônio
18.
Int J Prosthodont ; 33(2): 212-216, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32069346

RESUMO

PURPOSE: To evaluate the effect of different concentrations of hydrofluoric acid (HF) on the surface roughness of a ceramic reinforced by lithium disilicate and on the bond strength formed between the ceramic and self-adhesive resin cement. MATERIALS AND METHODS: A total of 100 disks of IPS e.max Press ceramic (Ivoclar Vivadent) reinforced by lithium disilicate were prepared as follows: group 1 remained untreated (control group); in groups 5-20, 5-40, and 5-60, the surfaces were etched with 5% HF for 20, 40, and 60 seconds, respectively; in groups 10-20, 10-40, and 10-60, the surfaces were etched with 10% HF for 20, 40, and 60 seconds, respectively; and in groups 10-20P, 10-40P, and 10-60P, the surfaces were etched with 10% HF for 20, 40, and 60 seconds, respectively, followed by treatment with 37% phosphoric acid for 5 seconds. Surface roughness and bond strength were analyzed with confocal microscopy and microshear testing, respectively. The values obtained were statistically analyzed using paired t test and two-way ANOVA followed by Tukey post hoc test at a 5% significance level. RESULTS: Surface roughness was influenced by the concentration and exposure time of acid applied (P < .05) and by the combination of these two factors (P < .05). Treatment with 10% HF for 40 seconds (group 10-40) achieved the highest roughness value. In contrast, bond strength was affected only by the acid exposure time (P < .05). CONCLUSION: Conditioning of lithium disilicate ceramics can change the surface morphology, thereby affecting bond strength with resin cement.


Assuntos
Colagem Dentária , Cerâmica , Porcelana Dentária , Teste de Materiais , Cimentos de Resina , Propriedades de Superfície
19.
Artigo em Inglês | MEDLINE | ID: mdl-32032411

RESUMO

In order to obtain a more-natural esthetic prothesis, the use of hybrid abutments is becoming widespread in implant dentistry. The aim of this in vitro study was to assess the effects of different surface treatments, as well as the effects of different combinations of surface treatments and cementation protocols, on the shear bond strength between titanium alloy disks and lithium disilicate glass-ceramics. Forty titanium-alloy disks (4 × 6.6 mm) were fabricated using computer-aided designed/computer-assisted manufacturing, and an identical number of lithium disilicate glass-ceramic disks of similar sizes were fabricated by a heat-pressing technique to be attached to the titanium disks. The specimens from each material group were divided into two groups (n = 20 each) according to the surface treatment type: alumina airborne-particle abrasion or etching with hydrofluoric acid. Each group was then divided into two subgroups (n = 10) depending on the resin-cement type: Multilink Hybrid Abutment Cement (Ivoclar Vivadent) or PANAVIA SA Cement Plus (Kuraray). After thermocycling (5,000 cycles), a shear bond strength (SBS) test was conducted using a universal testing machine. Statistical analysis was performed by analysis of one-way analysis of variance and unpaired tests (P < .05). Statistically, the highest SBS values were obtained using airborne-particle abrasion. The surface treatment of titanium alloys by sandblasting led to a higher SBS compared to etching with hydrofluoric acid. The cement type also had a significant influence on SBS results.


Assuntos
Colagem Dentária , Titânio , Ligas , Cerâmica , Porcelana Dentária , Análise do Estresse Dentário , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento , Propriedades de Superfície
20.
Am J Dent ; 33(1): 33-38, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32056413

RESUMO

PURPOSE: To evaluate the effect of different contamination media and cleaning regimens on the adhesion of resin cement to lithium disilicate ceramic. METHODS: Specimens (IPS e.max CAD) (n =15 per group) were etched with 5% hydrofluoric acid gel. While half of the specimens were silanized after etching, the other half was left etched only. After contamination with either saliva or dental stone, they were further divided into four subgroups depending on the cleaning regimens: water rinsing only (WR), 80% ethanol (E), 37% phosphoric acid (PA), cleaning gel (CG). All specimens were re-silanized, coated with adhesive resin (Heliobond) and resin cement (Variolink II) was bonded. After thermocycling (5.000x, 5-55°C), ceramic-cement interface was loaded under shear (1 mm/minute) and failure types were classified. Data (MPa) were analyzed using 3-way ANOVA, Dunnett-T3 tests and Weibull moduli were calculated. RESULTS: Saliva contamination (4.7±2.2-15.4±2.7) resulted in significantly lower bond strength compared to dental stone (17.8±4.8-23.6±2.7). Silanization before contamination showed protective effect especially for saliva (20.1±4.5-24.7±3.9) compared to non-silanized groups (4.7±2.2-15.4±2.7). Weibull modulus was the lowest for saliva-contaminated groups after cleaning with WR (2.22, 5.01) or E (1.14, 5.77) without and with initial silanization, respectively. Adhesive failures (272 out of 285) were commonly observed in all groups. Saliva contamination decreased the adhesion of luting cement to lithium disilicate ceramic considerably more than dental stone contamination, but silanization prior to try-in prevented deterioration in adhesion. CLINICAL SIGNIFICANCE: Preliminary silanization of hydrofluoric acid etched lithium disilicate ceramic prior to saliva or dental stone contamination re-established resin luting cement adhesion, irrespective of the cleaning regimen used.


Assuntos
Colagem Dentária , Cerâmica , Cimentos Dentários , Porcelana Dentária , Análise do Estresse Dentário , Ácido Fluorídrico , Teste de Materiais , Cimentos de Resina , Propriedades de Superfície
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