RESUMO
OBJECTIVE: The aim of this study was to evaluate the effect of an adhesive loaded with 0.2 % copper (Cu) and 5 % zinc oxide (ZnO) nanoparticles (Nps) on its adhesive properties and enzymatic activity at the hybrid layer ex vivo in a randomized clinical model. METHODS: Fifteen patients participated in this study, and a total of 30 third molars were used. Occlusal cavities (4 × 4 × 2 mm) were made in each tooth, and randomly divided into 2 groups: (i) Experimental group: commercial adhesive loaded with 0.2wt % CuNps and 5wt % ZnONps; and (ii) Control Group: non-loaded commercial adhesive. Teeth were restored with resin composite. Thirty days later, extractions were performed. Extracted teeth were longitudinally sectioned. Nps in powder were characterized by field emission scanning electron microscope (FE-SEM) and energy dispersive X-ray (EDX) analysis. Microtensile bond strength (µTBS), degree of conversion (DC), and nanoleakeage (NL) tests were executed. In situ zymography (Zym) was performed to evaluate the gelatinolytic activity at the hybrid layer. Student's t-test (α = 0.05) was applied for all tests. RESULTS: µTBS and DC did not show significant differences (p > 0.05) between both groups. However, NL and gelatinolytic activity at the hybrid layer showed significant values (p < 0.05) for experimental group in comparison with control group. CONCLUSION: The addition of 0.2 % CuNps and 5 % ZnONps to a universal adhesive decreases NL and gelatinolytic activity at the hybrid layer, without jeopardizing its adhesive properties. SIGNIFICANCE: This randomized clinical trial with ex vivo analysis demonstrate that a commercial adhesive modified with 0.2wt % Cu and 5wt % ZnO Nps that does not affect its adhesive properties, reducing gelatinolytic activity and nanoleakage at the hybrid layer, which should contribute to an improvement of long term bonding-dentine clinical performance.
Assuntos
Resinas Compostas , Cobre , Colagem Dentária , Microscopia Eletrônica de Varredura , Resistência à Tração , Óxido de Zinco , Humanos , Óxido de Zinco/química , Cobre/química , Colagem Dentária/métodos , Resinas Compostas/química , Nanopartículas/química , Adesivos Dentinários/química , Dentina/efeitos dos fármacos , Dentina/enzimologia , Teste de Materiais , Masculino , Cimentos de Resina/química , Adulto , Feminino , Propriedades de Superfície , Cimentos Dentários/química , Dente Serotino , Restauração Dentária Permanente/métodos , Espectrometria por Raios XRESUMO
ER:YAG laser and experimental resin-based dental adhesive loaded with functionalized carbonated apatite filler were used in this study to evaluate the dentin interaction in terms of penetration and occlusion of the dentinal tubules aiding in the control of dentin hypersensitivity (DH). Spheroidal Carbonated apatite nanoparticles (N-CAP), with an average size of 20±5 nm diameter, were synthesized, characterized, and incorporated in a universal adhesive "All Bond Universal, Bisco, USA", in (2% weight) concentration. Er:YAG laser "Lightwalker, FOTONA, EU" was adjusted to an energy output of 40mJ/ pulse and pulse repetition of 10 Hz for 10 seconds. Dentin specimens were prepared from the buccal surface of 75 extracted sound human molars. The specimens were randomly divided into five groups (n=15) according to the surface treatment: Group (L): Laser only; Group (LB): Laser in combination with adhesive; Group (LBN): Laser in combination with adhesive loaded with N-CAP; Group (B): adhesive only; and Group (BN): adhesive loaded with N-CAP. Depth of penetration and occlusion of the dentinal tubules were assessed using Environmental Scanning Electron Microscope Examination (ESEM). One-way ANOVA was used to compare groups, followed by a pairwise test for multiple comparisons (α=0.05). Groups (LB), and (LBN) showed the highest mean of dentinal tubules' penetration, with a non-significant difference between them. In contrast, the specimens treated with laser only (L) showed the most minor penetration. The employment of ER-YAG laser irradiation with the adhesive loaded with N-CAP was evaluated to be effective in penetrating and occluding the opened dentinal tubules.
Assuntos
Lasers de Estado Sólido , Lasers de Estado Sólido/uso terapêutico , Humanos , Apatitas/química , Dentina , Microscopia Eletrônica de Varredura , Nanopartículas/química , Sensibilidade da Dentina , Técnicas In Vitro , Cimentos Dentários/químicaRESUMO
Objective: To evaluate the enamel bonding ability and orthodontic adhesive resin degree of conversion using the experimental bracket design. Material and Methods. Thirteen bovine teeth were used in the study. The experimental bracket was modified with a translucent region in the center of its body. After enamel etching, Orthocem orthodontic adhesive (FGM, Joinville, Brazil) was applied on the bracket base for bonding. The groups were divided as follows (n = 10 per group): (1) control (CB) with standard brackets and (2) spot bracket (SB) with experimental brackets featuring a 0.8 mm translucent region at the center using carbide bur. Shear bond strength (SBS) was evaluated after 24 hours in a universal testing machine and adhesive remnant index (ARI). The degree of conversion (DC) was analyzed using Raman spectroscopy (n = 3 per group). Data were then analyzed using Student's t-test and Mann-Whitney statistical methods. Results: The SB group exhibited a higher mean SBS (10.33 MPa) compared to the CB Group (8.77 MPa). However, there was no statistical difference between the groups (p = 0.376). Both SB and CB groups had a mean ARI score of 1. Raman analysis revealed a higher degree of conversion in the SB group (49.3%) compared to the CB group (25.9%). Conclusions: The experimental support showed a higher degree of adhesive conversion, although there was no significant increase in bond strength.
Assuntos
Resinas Compostas , Colagem Dentária , Esmalte Dentário , Braquetes Ortodônticos , Polimerização , Resistência ao Cisalhamento , Animais , Bovinos , Colagem Dentária/métodos , Esmalte Dentário/química , Resinas Compostas/química , Teste de Materiais , Cimentos Dentários/química , Cimentos de Resina/químicaRESUMO
OBJECTIVES: Evaluate, in vitro, the effect of incorporating nano-sized sodium trimetaphosphate (TMPnano) and phosphorylated chitosan (Chi-Ph) into resin-modified glass ionomer cement (RMGIC) used for orthodontic bracket cementation, on mechanical, fluoride release, antimicrobial and cytotoxic properties. METHODS: RMGIC was combined with Chi-Ph (0.25%/0.5%) and/or TMPnano (14%). The diametral compressive/tensile strength (DCS/TS), surface hardness (SH) and degree of conversion (%DC) were determined. For fluoride (F) release, samples were immersed in des/remineralizing solutions. Antimicrobial/antibiofilm activity was evaluated by the agar diffusion test and biofilm metabolism (XTT). Cytotoxicity in fibroblasts was assessed with the resazurin method. RESULTS: After 24 h, the RMGIC-14%TMPnano group showed a lower TS value (p < 0.001); after 7 days the RMGIC-14%TMPnano-0.25%Chi-Ph group showed the highest value (p < 0.001). For DCS, the RMGIC group (24 h) showed the highest value (p < 0.001); after 7 days, the highest value was observed for the RMGIC-14%TMPnano-0.25%Chi-Ph (p < 0.001). RMGIC-14%TMPnano, RMGIC-14%TMPnano-0.25%Chi-Ph, RMGIC-14%TMPnano-0.5%Chi-Ph showed higher and similar release of F (p > 0.001). In the SH, the RMGIC-0.25%Chi-Ph; RMGIC-0.5%Chi-Ph; RMGIC-14%TMPnano-0.5%Chi-Ph groups showed similar results after 7 days (p > 0.001). The RMGIC-14%TMPnano-0.25%Chi-Ph group showed a better effect on microbial/antibiofilm growth, and the highest efficacy on cell viability (p < 0.001). After 72 h, only the RMGIC-14%TMPnano-0.25%Chi-Ph group showed cell viability (p < 0.001). CONCLUSION: The RMGIC-14%TMPnano-0.25%Chi-Ph did not alter the physical-mechanical properties, was not toxic to fibroblasts and reduced the viability and metabolism of S. mutans. CLINICAL RELEVANCE: The addition of phosphorylated chitosan and organic phosphate to RMGIC could provide an antibiofilm and remineralizing effect on the tooth enamel of orthodontic patients, who are prone to a high cariogenic challenge due to fluctuations in oral pH and progression of carious lesions.
Assuntos
Antibacterianos , Biofilmes , Quitosana , Fibroblastos , Fluoretos , Cimentos de Ionômeros de Vidro , Teste de Materiais , Quitosana/farmacologia , Antibacterianos/farmacologia , Cimentos de Ionômeros de Vidro/farmacologia , Cimentos de Ionômeros de Vidro/química , Biofilmes/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fosforilação , Fluoretos/farmacologia , Dureza , Resistência à Tração , Propriedades de Superfície , Força Compressiva , Nanopartículas , Cimentos de Resina/química , Polifosfatos/farmacologia , Cimentos Dentários/farmacologia , Cimentos Dentários/química , Sobrevivência Celular/efeitos dos fármacos , Streptococcus mutans/efeitos dos fármacos , Animais , Fosfatos/farmacologia , Humanos , Braquetes OrtodônticosRESUMO
OBJECTIVES: This study aimed to evaluate the impact of various commercial silane brands with varied chemical compositions with or without the application of an adhesive layer on the microshear bond strength and durability of a resin luting agent to lithium disilicate glass ceramic. METHODS AND MATERIALS: Lithium disilicate glass ceramic discs (EMX, IPS e.max Press, Ivoclar Vivadent) measuring 10 mm in diameter and 3 mm in thickness were fabricated (n=240). Surfaces were etched using 5% hydrofluoric acid and randomly assigned to 10 groups based on the commercial brand of silane used (n=24): [RP] RelyX Ceramic Primer (3M ESPE); [PS] Prosil (FGM); [SA] Silano (Angelus); [SM] Silano (Maquira); [SU] Silane (Ultradent); [GL] GLUMA Ceramic Primer (Kulzer); [CB] Ceramic Bond (VOCO); [MB] Monobond N (Ivoclar Vivadent); [CP] Clearfil Ceramic Primer (Kuraray); and [DE] 2-step silane (Dentsply Sirona). Half of the EMXs (n=12) received a thin adhesive layer (+) after the silane and prior to resin luting agent, while the other half (n=12) did not receive an adhesive layer (-). For the microshear bond strength test (µSBS), four light-cured resin luting agent cylinders (1 mm in diameter) were created on each EMX surface. Half of these specimens were tested after 24 hours, while the other half were stored in deionized water for 6 months. The µSBS test was conducted using a universal testing machine (DL 500, EMIC) at a crosshead speed of 1 mm/min until failure. The obtained data underwent statistical analysis using analysis of variance (ANOVA) and the Tukey test (α=0.05). RESULTS: There was significant influence of the silane commercial brand on bond strength. Notably, "universal primers" yielded lower bond strength results compared to "pure" silane solutions. Water storage had a detrimental effect on microshear bond strength for certain silane commercial brands. Additionally, the application of an adhesive layer negatively impacted bond strength results for all silanes. CONCLUSIONS: This study confirms the importance of both silane commercial brand and chemical composition in relation to bond strength of resin luting agents to lithium disilicate glass ceramic. Furthermore, the application of an adhesive layer may have an adverse effect on bond stability over time.
Assuntos
Cerâmica , Colagem Dentária , Porcelana Dentária , Análise do Estresse Dentário , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento , Silanos , Porcelana Dentária/química , Silanos/química , Cerâmica/química , Colagem Dentária/métodos , Cimentos de Resina/química , Propriedades de Superfície , Cimentos Dentários/química , Condicionamento Ácido do Dente/métodos , HumanosRESUMO
Acidic pH can modify the properties of repair cements. In this study, volumetric change and solubility of the ready-to-use bioceramic repair cement Bio-C Repair (BCR, Angelus, Londrina, PR, Brazil) were evaluated after immersion in phosphate-buffered saline (PBS) (pH 7.0) or butyric acid (pH 4.5). Solubility was determined by the difference in initial and final mass using polyethylene tubes measuring 4 mm high and 6.70 mm in internal diameter that were filled with BCR and immersed in 7.5 mL of PBS or butyric acid for 7 days. The volumetric change was established by using bovine dentin tubes measuring 4 mm long with an internal diameter of 1.5 mm. The dentin tubes were filled with BCR at 37°C for 24 hours. Scanning was performed with micro-computed tomography (micro-CT; SkyScan 1176, Bruker, Kontich, Belgium) with a voxel size of 8.74 µm. Then, the specimens were immersed in 1.5 mL of PBS or butyric acid at and 37 °C for 7 days. After this period, a new micro-CT scan was performed. Bio-C Repair showed greater mass loss after immersion in butyric acid when compared with immersion in PBS (p<0.05). Bio-C Repair showed volumetric loss after immersion in butyric acid and increase in volume after immersion in PBS (p<0.05). The acidic pH influenced the solubility and dimensional stability of the Bio-C Repair bioceramic cement, promoting a higher percentage of solubility and decrease in volumetric values.
Assuntos
Óxidos , Materiais Restauradores do Canal Radicular , Animais , Bovinos , Solubilidade , Óxidos/química , Compostos de Cálcio/química , Microtomografia por Raio-X , Ácido Butírico , Teste de Materiais , Cimentos Dentários/química , Cimentos de Ionômeros de Vidro , Concentração de Íons de Hidrogênio , Silicatos/química , Materiais Restauradores do Canal Radicular/químicaRESUMO
This study aimed to evaluate the interface of universal adhesive (UA) with bulk-fill resin (BF) and dentin, after endodontic irrigation. The pulp chamber of 96 molars was irrigated with chlorhexidine 2% (CHX) or sodium hypochlorite 5.25% (NaOCl) and restored according to three restorative protocols. Microtensile bond strength (µTBS) and nanoleakage tests were performed after 24 h of thermocycling. Kruskal Wallis, Mann-Whitney and Wilcoxon were performed (p < 0.05). Comparing restorative systems, a difference was found only when irrigated with CHX after 24 h. CHX provided higher µTBS than NaOCl after 24 h for two restorative protocols; after thermocycling, NaOCl provided the greatest µTBS than CHX for one group. Decreased µTBS was observed for all restorative systems when CHX was used after thermocycling. NaOCl demonstrated the highest nanoleakage. The composition of UA influenced the immediate adhesion and sealing to BF when CHX was used; ageing has a deteriorating effect on adhesion and sealing for all restorative systems.
Assuntos
Colagem Dentária , Humanos , Técnicas In Vitro , Colagem Dentária/métodos , Irrigantes do Canal Radicular/química , Hipoclorito de Sódio/química , Resistência à Tração , Infiltração Dentária , Resinas Compostas/química , Clorexidina/farmacologia , Clorexidina/química , Cimentos de Resina/química , Teste de Materiais , Cimentos Dentários/químicaRESUMO
OBJECTIVE: To evaluate the influence of antioxidants (ATX) resveratrol, winter's bark, green tea and yerba mate on the bond strength between bleached enamel and the nanohybrid composite resin. METHODOLOGY: Bovine incisor crowns (n = 132) were randomly divided into 22 groups (n = 6) according to the application times (5, 10, 15, 30, and 60 min) of each antioxidant. Teeth restored without previous bleaching or ATX constituted the non-bleached control group (NB Ctrl) (n = 6), and teeth restored after bleaching and without ATX represented the bleached control group (B Ctrl) (n = 6). The 35 % hydrogen peroxide was applied for 45 min (3 application of 15 min) to the buccal enamel surface. ATX was used after bleaching for the specified time of each group and removed with air-water spray. The enamel was etched with 37 % phosphoric acid (30 s) and rinsed with air-water spray. The adhesive resin was applied to the enamel dry surface. Teeth were restored using 1 mm composite resin increments (10 × 10 × 3 mm) and sectioned in test specimens of 6 mm in length and 1 mm2 in cross-sectional area submitted to microtensile bond strength test (0.5 mm/min). The load (N) at failure was recorded, and the bond strength (σt) was calculated (MPa). The fracture area was analyzed under optical microscopy, and failures were classified as cohesive, mixed, or adhesive. Data was evaluated by Kruskal-Wallis and Dunn tests (p ≤ 0.05). RESULTS: B Ctrl group presented lower σt than NB Ctrl (p < 0.001). Applying resveratrol for 5 or 10 min, winter's bark for 10 or 15 min, green tea for less than 15 min, and yerba mate for 15 min provided similar σt between bleached enamel and nanohybrid composite to the control group. CONCLUSION: Restorative procedures performed immediately after tooth bleaching compromises adhesion. Experimental antioxidants applied to bleached enamel can increase the immediate bond strength of restorations performed directly after bleaching, with similar values to those observed in unbleached enamel. CLINICAL SIGNIFICANCE: This study presents promising results to support the use of antioxidants on the recently bleached enamel to allow adhesive tooth restorations. The immediate bonding obtained using antioxidants was similar to the one achieved in non-bleached enamel in brief application times. Green tea extract and resveratrol were able to restore the bond strength to bleached enamel in a short application time of 5 min. The reduction in the required application time holds the potential to decrease the overall duration of the clinical section, offering clinical advantages and improving the feasibility of using antioxidants on the bleached enamel prior to adhesive procedures.
Assuntos
Anti-Infecciosos , Colagem Dentária , Clareamento Dental , Animais , Bovinos , Antioxidantes/farmacologia , Antioxidantes/química , Resveratrol/farmacologia , Colagem Dentária/métodos , Cimentos Dentários/farmacologia , Cimentos Dentários/química , Clareamento Dental/métodos , Resinas Compostas/farmacologia , Resinas Compostas/química , Esmalte Dentário , Anti-Infecciosos/farmacologia , Chá , Água , Resistência ao CisalhamentoRESUMO
OBJECTIVES: To evaluate the effect of bromelain associated with Biosilicate on the bond strength (BS) of a universal adhesive system to sound (SD) and caries-affected dentin (CAD), and on the proteolytic activity. MATERIALS AND METHODS: Cavities were prepared in 360 molars, half submitted to cariogenic challenge. Teeth were separated into groups (n=20): Control-No treatment; CHX-0.12% chlorhexidine; NaOCl-5% sodium hypochlorite; Br5%-5% bromelain; Br10%-10% bromelain; Bio-10% Biosilicate; NaOClBio-NaOCl+Bio; Br5%Bio-Br5%+Bio; Br10%Bio-Br10%+Bio. Following treatments, the adhesive system was applied, and cavities were restored. Samples were sectioned into sticks and stored at 37 °C for 24 h, 6 months, and 1 year. Microtensile BS (2-way ANOVA, Bonferroni's test, α=0.05), fracture patterns (SEM), and adhesive interfaces (TEM) were evaluated. Bacterial collagenase assay and in situ zymography were performed. RESULTS: In CAD, Br10% presented higher BS (p=0.0208) than Br5%Bio. Br5% presented higher BS (p=0.0033) after 6 months than after 24 h; and association of treatments, higher BS (p<0.05) after aging than after 24 h. Mixed fractures were the most prevalent. Association of treatments promoted a more uniform hybrid layer with embedded Bio particles. Experimental groups presented lower (p<0.0001) relative fluorescence units than Control. Bromelain, associated or not with Bio, showed collagenolytic degradation. CONCLUSIONS: Bromelain associated with Biosilicate did not affect the BS to SD. In CAD, Br5%Bio decreased immediate BS but had no long-term influence. This association decreased the proteolytic activity. CLINICAL RELEVANCE: Bromelain and Biosilicate may enhance the longevity of adhesive restorations by inhibiting endogenous proteases.
Assuntos
Colagem Dentária , Cárie Dentária , Humanos , Cimentos Dentários/química , Adesivos Dentinários/química , Bromelaínas/farmacologia , Bromelaínas/análise , Teste de Materiais , Dentina , Cerâmica , Resistência à Tração , Cimentos de Resina/farmacologiaRESUMO
The present study aimed to evaluate the influence of application mode on the short-term microshear bond strength longevity of self-etching and universal adhesive systems to enamel, the failure mode, and the resulting enamel surface micromorphology. Ninety enamel surfaces were obtained from sound third molars, planed, and randomly assigned to nine groups, according to the application mode and the adhesive system (n=10). There were three primer application modes: according to the manufacturer's recommended application time (control), using double the application time recommended for the primer and selective enamel etching. The adhesive systems used were: Clearfil SE Bond (Kuraray), FL-Bond II (SHOFU), and Futurabond U (Voco). At least two resin-bonded composite cylinders (Grandioso Light Flow, Voco) were placed on each enamel surface, and then evaluated for microshear bond strength at 24 hours and 180 days of storage in solution body fluid (SBF) at pH 7.4. Failure modes were evaluated with a stereoscopic microscope at 20× magnification. A micromorphological analysis of the enamel surface was performed under a scanning electron microscope at 5000× magnification before and after the treatments. Mixed models for repeated measures over time showed significant interaction among application modes, adhesive systems, and time periods (p=0.0331). The bond strength of FL-Bond II adhesive to enamel observed after performing selective enamel etching was significantly higher than that observed after applying the control treatment (p=0.0010) at both 24 hours and 180 days. However, no significant difference was observed between the application of this same adhesive at double the time recommended by the manufacturer and the other two application modes (p>0.05). There was also no significant difference in the microshear bond strength for the enamel treatments applied using Clearfil SE Bond and Futurabond U (p>0.05). A significant reduction in bond strength to enamel was observed at the 180-day storage time for all the adhesive systems when selective enamel etching was performed (p<0.0001). No significant association was observed between the adhesive system failure mode and the enamel treatments (p=0.1402 and p=0.7590 for 24 hours and 180 days, respectively). The most prevalent failure was the adhesive type.