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1.
Clin Oral Investig ; 2020 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-33200282

RESUMEN

OBJECTIVES: This study investigated the ability of modified phosphoric acids containing chlorhexidine (CHX) or grape seed extract (GSE) for promoting simultaneous biomodification during acid etching on bonding properties in caries-affected dentin (CAD). MATERIALS AND METHODS: Thirty-two human molars (8 with sound dentin [SD] and 24 naturally CAD) were selected for the study. The SD and CAD were initially exposed, then randomized and etched according to the following groups: (1) SD (SD-CT) and CAD (CAD-CT) both with 37% phosphoric acid, (2) CAD with 2% CHX containing 37% phosphoric acid (CAD-CHX), and (3) CAD with 2% GSE containing 10% phosphoric acid (CAD-GSE). The bonding procedure and composite build-ups were performed after acid etching. Subsequently, they were sectioned in resin-dentin specimens. The specimens were submitted for chemical profiling by micro-Raman, microtensile bond strength (µTBS), failure mode with chemical characterization by FEG/SEM-EDX, and in situ zymography by CLSM. The data from µTBS and CLSM were statistically analyzed (1-way ANOVA and Tukey's test; α = 0.05). RESULTS: The highest µTBS results were shown for SD-CT in comparison with all CAD groups (p < 0.001), and the lowest for CAD-CT and CAD-CHX (p < 0.001). The etching with CHX did not increase the µTBS for CAD when compared with CT (p = 0.52). However, the etching with GSE improved significantly the µTBS for CAD when compared with CT and CHX (p < 0.001). The chemical profile detected chemical and structural changes in collagen peaks for CAD-CT, which were not detected when the CAD was etched by modified acids. Also, the poorest hybridization ability was detected in CAD for CT, which was significantly improved with modified acids, especially the GSE, as evaluated by chemical profile and failure mode. A significant reduction of MMP activity on CAD was promoted by modified acids in comparison with CT (both p < 0.001). CONCLUSIONS: The GSE-containing acid was able to promote biomodification during the acid etching, increasing the bonding properties and reducing the activity of the MMPs within the hybrid layer. CLINICAL RELEVANCE: The use of GSE-containing phosphoric acid can be a promising alternative to improve the bonding performance on caries-affected dentin, since it is capable of biomodifying the dentin during the acid etching, without adding any extra step in bonding procedures.

2.
J Esthet Restor Dent ; 2020 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-32949453

RESUMEN

OBJECTIVE: This study evaluated the hydrogen peroxide (HP) penetration inside the pulp cavity and the color change of teeth submitted to the 15% carbamide peroxide (CP) nanoparticle bleaching gel at several application times. MATERIALS AND METHODS: Premolars were divided into nine groups (n = 6) according to 15% CP bleaching agents (nanoparticle and commercial) and to application times (15, 30, 45, and 60 minutes). A negative control was exposed to ultra-purified water. After a whitening procedure, the HP concentration (µg/mL) inside the pulp cavity was assessed via spectrophotometry. The color change (ΔE* and ΔE00*) was evaluated with a spectrophotometer. Data were analyzed via two-way ANOVA and Tukey (α = 0.05). RESULTS: A lower concentration of HP was detected for CP nanoparticle gel after 30 and 45 minutes of whitening procedure (P = .001). The bleaching groups promoted a higher color change (ΔE* and ΔE00*) regardless of the application time (P = .0001). CONCLUSIONS: The CP nanoparticle gel reduced HP inside the pulp cavity, and showed effective bleaching compared with CP commercial gel. CLINICAL SIGNIFICANCE: Using 15% carbamide peroxide nanoparticle bleaching gel decreased the HP penetration inside the pulp cavity and may decrease bleaching-induced tooth sensitivity in at-home bleaching.

3.
Dent Mater ; 2020 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-32933775

RESUMEN

OBJECTIVE: To evaluate the five-year clinical performance of Scotchbond Universal Adhesive (SU; 3M Oral Care, St. Paul, MN, USA) in non-carious cervical lesions (NCCLs) using two evaluation criteria. METHODS: Thirty-nine patients participated in this study. Two hundred restorations were assigned to four groups: SU-ERm: etch-and-rinse + moist dentin; SU-ERd: etch-and-rinse + dry dentin; SU-Set: selective enamel etching; and SU-SE: self-etch. A nanofilled composite resin was placed incrementally. The restorations were evaluated at baseline and after 5 years using both the World Dental Federation (FDI) and the United States Public Health Service (USPHS) criteria. The survival rates (retention/fractures) were calculated with the Kaplan-Meier and the log-rank test. For the secondary outcomes, Friedman repeated measures analysis of variance by rank was applied (α = 0.05). RESULTS: After 5 years the recall rate was 86%. The retention/fracture rates were 93% for Erm and ERd, 88.4% for SEet and 81.4% for SE. A significant difference was observed for SE vs. ERd and SE vs. ERm (p = 0.01). Also, marginal discoloration and adaptation showed significant differences with ERm and ERd resulting in fewer marginal discrepancies than SE (p < 0.05). SIGNIFICANCE: After 5 years, the clinical behavior of the universal adhesive in the etch-and-rinse strategy was better when compared to the self-etch strategy. The use of selective enamel etching is highly recommended for the self-etch strategy. The FDI and USPHS evaluation criteria showed similar results after 5 years.

4.
Clin Cosmet Investig Dent ; 12: 327-333, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32848479

RESUMEN

Introduction: Osteonecrosis of the jaw is a condition associated with intraoral ulceration and bone necrosis induced by antiresorptive medications, such as zoledronic acid, a bisphosphonate. Previous data on Arrabidaea chica (H&B.) Verlot wound healing activity prompted the study reported herein on A. chica standardized hydro alcoholic extract in vitro cytoprotective activity data on epithelial and osteoblastic cells exposed to zoledronic acid (ZA). Methods: Primary human gingival fibroblasts and murine pre-osteoblasts were treated with ZA 10 µM together with 5 or 10 µg.mL-1 A. chica extract for 24h and 48 h. At both times, cells were submitted to viability assay and caspase 3/7 activation evaluation. Statistical analysis used one-way ANOVA and p=0.05. Results: In cell viability assay, a drastic damage effect of ZA appeared after 48 h in both epithelial (55.8%) and pre-osteoblastic cells (39.7%). When treated with ZA in combination with A. chica extract, cells showed higher viability values: 74.1%-82.3% for fibroblasts and 66% for pre-osteoblasts. Furthermore, the combined treatment presented lower caspase 3/7 activation in fibroblasts and pre-osteoblasts. Conclusion: At low concentrations, A. chica extract showed promising cytoprotective effects against ZA-induced damage actions; however, further in vitro and in vivo studies are required to establish the mechanism of action.

5.
Dent Mater ; 36(5): 672-680, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32284197

RESUMEN

OBJECTIVE: The present study investigated the ability of a chlorhexidine (CHX)-containing primer (0.2% aqueous solution) to inhibit dentinal enzymes, preserve the hybrid layer (HL) and remain within the HL, after 10 years of aging in artificial saliva at 37°C. METHODS: Non-carious extracted molars were assigned to two groups, cut into slabs exposing middle/deep dentin, etched and bonded with Adper Scotchbond 1XT (SB1XT) with or without 0.2% CHX aqueous solution pretreatment. Composite build-ups were made, and the specimens were cut in 1-mm thick bonded sticks. In situ zymography was performed on freshly prepared specimens (T0) and specimens aged for 10 years (T10-yr) at 37°C in artificial saliva, to investigate endogenous gelatinolytic activity within the HL. At T10-yr, specimens were also decalcified and embedded in epoxy resin for TEM analysis. Micro-Raman spectroscopy was performed at T0 and T10-yr to evaluate the chemical profiles in intertubular dentin and the HL. RESULTS: In situ zymography showed less pronounced enzymatic activity in the CHX-pretreated group (p<0.05) regardless of aging, maintaining a similar level of fluorescence at T0 and T10-yr (p>0.05). TEM results showed that 98% of the HL had been degraded in the control group, while 95% of the HL was intact in the experimental group. Moreover, all the Raman spectra peaks assigned to CHX could be identified only in the CHX-pretreated group (T0 and T10-yr). SIGNIFICANCE: In vitro, CHX remains in the HL after 10 years with its inhibitory effect preserved. This may be the underlying factor for HL preservation after this long aging period.

6.
Clin Oral Investig ; 24(2): 809-822, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31190231

RESUMEN

OBJECTIVES: The aim of this study was to investigate the effects of collagen cross-linking agents on nanomechanical and bonding properties of eroded dentin (ED), 24 h and 2 years after water storage. MATERIALS AND METHODS: Human molar dentin surfaces, eroded by soft drinks or citric acid, were acid-etched and treated with primers containing proanthocyanidin (PA) and riboflavin (RI) or were untreated (control) and tested after 24 h and 2 years. After acid etching and adhesive application (Prime&Bond Elect (PBE); Scotchbond Universal (SBU); Tetric n-bond Universal (TEU)), specimens were sectioned into beams and tested for microtensile bond strength (µTBS) and silver nitrate deposition (NL) after 24 h and 2 years. The beams were used to evaluate the 24-h in situ conversion of degree (DC). Nanohardness (NH) and Young's modulus (YM) were evaluated via resin-bonded dentin slices after 24 h and 2 years. A three-way ANOVA and Tukey's test were used for statistical analysis (5%). RESULTS: For both storage times, ED with citric acid resulted in lower µTBS, NH, and YM and higher NL for each adhesive system than soft drink ED (p < 0.05). After 2 years of water storage, cross-linking primers maintained the µTBS, NH, and YM (p < 0.05) when compared with the control group. Althougth, the NL values decreased for all groups after 2 years of water storage, PA and RI treatments showed NI values lower than control group (p < 0.001). No significant differences were observed between PA and RI treatments (p > 0.05). Cross-linking primers maintain or improve DC (p < 0.03). In general, TEU and SBU yielded higher µTBS, DC, NH, and YM and lower NL than PBE. CONCLUSION: Cross-linking agents improved the results and maintained the resin-ED interface bonding and nanomechanical properties, without jeopardizing adhesive polymerization. CLINICAL RELEVANCE: Cross-linking agents are a viable alternative for improving and maintaining resin-ED interface bonding and nanomechanical properties.


Asunto(s)
Recubrimiento Dental Adhesivo , Colágeno , Resinas Compuestas , Dentina , Recubrimientos Dentinarios , Humanos , Ensayo de Materiales , Cementos de Resina , Resistencia a la Tracción , Agua
7.
Am J Dent ; 32(5): 235-239, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31675191

RESUMEN

PURPOSE: To evaluate the effect of whitening mouthrinses on sorption (SP) and solubility (SL), percentage of microhardness change (%M), loss of surface (LS), and color change (ΔE) in bulk-fill composites when compared with conventional composites. METHODS: Three bulk-fill composites, Surefil SDR (SF), Filtek Bulk-Fill (BF), and Filtek Bulk-Fill Flow (BFF), and one conventional resin, Filtek Z350 (FZ), were selected. Eighteen samples of each composite were subdivided into three groups based on the type of treatment: Listerine Whitening mouthrinse (LW), Colgate Plax Whitening mouthrinse (CP), and distilled water (DW; control). The samples were prepared according to ISO 4049:2009. Color, roughness, and microhardness were evaluated before and after treatment, while SP and SL values were measured after treatment. The surface morphology of the specimen was examined using scanning electron microscopy. Data were analyzed using two-way ANOVA and Tukey's test. RESULTS: FZ presented significantly lower ΔE when immersed in DW. Additionally, LS was lowest in FZ when compared with the other resins. SF and BFF demonstrated high %M. SL was significantly higher in SF, whereas SP was lowest in BFF after CP treatment. No significant alterations in surface morphology were noted in the BF composites. The BF composites showed a decrease in their properties after immersion in the two types of mouthrinses or in DW, without alterations in the surface morphology. CLINICAL SIGNIFICANCE: Flowable bulk-fill composites showed the greatest changes in their properties when exposed to different mouthrinses or water. Thus, they should be used with caution in areas that will stay exposed to the oral cavity.


Asunto(s)
Resinas Compuestas , Ensayo de Materiales , Solubilidad
8.
J Dent ; 90: 103219, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31629030

RESUMEN

OBJECTIVE: This study aimed to evaluate the addition of copper nanoparticles (CuNp) on the clinical performance of a universal adhesive system used as etch-and-rinse (ER) and self-etch (SE). METHODS: 216 restorations were randomly placed in 36 subjects according to the following groups: ERcu = etch-and-rinse with 0.1% CuNp; ERct = etch-and-rinse without CuNp; SEcu = self-etch with 0.1% CuNp; SEct = self-etch without CuNp. Resin composite was placed incrementally and light-cured. The restorations were evaluated at baseline and 6, 12 and 18 months using the FDI and USPHS criteria. Statistical analyses were performed using appropriate tests (α = 0.05). RESULTS: The addition of CuNp did not increase the clinical performance (FDI / USPHS) of the universal adhesive tested after 18-month when applied in the ER mode (p > 0.05). The addition of CuNp in SE restorations increased the retention rate significantly and decreased the marginal discrepancies after 18 months (p < 0.05). CONCLUSION: The clinical performance of universal adhesive was significantly increased when applied in the SE mode with the addition of copper nanoparticles. CLINICAL RELEVANCE: This is the first study that demonstrates a slight improvement in the clinical performance of universal adhesive systems in non-carious cervical lesions when added CuNp in lower concentration.


Asunto(s)
Cobre/química , Recubrimiento Dental Adhesivo , Restauración Dental Permanente/métodos , Recubrimientos Dentinarios/química , Cementos de Resina/química , Cuello del Diente/patología , Resinas Compuestas/química , Cementos Dentales , Fracaso de la Restauración Dental , Método Doble Ciego , Humanos
9.
J Adhes Dent ; 21(2): 149-158, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30949628

RESUMEN

PURPOSE: To evaluate the effect of two phosphoric acids containing protease inactivators (chlorhexidine and proanthocyanidin) on the resin/eroded-dentin microtensile bond strength (µTBS), nanoleakage (NL), and in situ degree of conversion (DC) of three universal adhesives applied in the etch-and-rinse mode. MATERIALS AND METHODS: One hundred twenty-six molars were randomly assigned to 18 experimental conditions according to the combination of the independent variables: eroded dentin (soft drink and citric acid), adhesive (Prime&Bond Elect [PBE, Dentsply Sirona], Scotchbond Universal Adhesive [SBU, 3M Oral Care], and Tetric N-Bond Universal [TEU, Ivoclar Vivadent]), and acid pretreatment (conventional phosphoric acid [CP acid]; chlorhexidine acid [CHX acid]; and proanthocyanidin acid [PA acid]). After restorations, specimens were sectioned into resin-dentin sticks (ca 0.8 mm2) that were then tested under tension (crosshead speed: 0.5 mm/min). Selected sticks from each tooth were used to evaluate NL and DC. Data from all tests were subjected to three-way ANOVA and Tukey's test (α=0.05). RESULTS: Dentin eroded with citric acid showed a significant reduction in µTBS for each adhesive in comparison to dentin eroded with the soft drink (p < 0.001). For dentin eroded with CHX acid and PA acid, the µTBS (p > 0.03) significantly improved and NL decreased for all adhesives (p < 0.004); in addition, the DC improved for two of the three adhesives tested (SBU and TEU) (p < 0.03) when CHX acid and PA acid were compared to CP acid. CONCLUSION: The addition of chlorhexidine and proanthocyanidin to phosphoric acid improved the adhesive performance when compared with conventional phosphoric acid, without jeopardizing adhesive polymerization at the resin/eroded-dentin interface.


Asunto(s)
Recubrimiento Dental Adhesivo , Filtración Dental , Grabado Ácido Dental , Resinas Compuestas , Dentina , Recubrimientos Dentinarios , Humanos , Ensayo de Materiales , Ácidos Fosfóricos , Cementos de Resina , Resistencia a la Tracción
10.
J Mech Behav Biomed Mater ; 92: 197-205, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30769251

RESUMEN

This study aimed at evaluating the use of biological dentin post (BDP), achieved by milling bovine root, through the analyses of mechanical and optical properties. BDPs were compared to a glass fiber post (GFP) in the following tests (n = 10): a) elastic modulus (E) and flexural resistance (σ) by three point bending test; b) fracture resistance (FR) by compressive load at 45° and failure pattern; c) light transmitting (LT) ability and their influence on the resin cement's degree of conversion (DC%); d) bond strength (BS) by push-out test and failure pattern. Bovine teeth were decoronated and root length was standardized at 14 mm. The canals were prepared and irrigated with 2.5% NaOCl. GFP's surface was conditioned by 1 min immersion in 24% H2O2 solution before silanization. After root embedment, the root canal walls and the BDP's surface were hybridized (H3PO4 37% + self-cured adhesive) for FR and DC% analyses. Posts were fixed into the root canals using a conventional dual resin cement. For BS test, both posts were luted using the conventional and the self-adhesive cementation. A universal testing machine (EMIC DL2000; 1 mm/min) was employed for the mechanical tests (E, σ, FR and BS). For the LT analysis, opaque polyethylene discs were transfixed by the posts, leaving 10 mm of the posts' apical section for measurements. Posts' cervical portion was irradiated (800 mW/cm2) and a spectrometer recorded the number of photons transmitted to previously chosen lateral post regions and at the apical tip. The resin cement DC% was evaluated in several sites of the cement film. After normal distribution were checked (Shapiro-Wilk test), data were submitted to ANOVA (5%) and Scheffe post-hoc test (5%). Results showed that: a) E: BDP > GFP; b) σ: BDP < GFP; c) RF: BDP < GFP; d) LT could not be observed for BDP. For GFPs, the greatest number of photons was observed at the post apical tip. An exponential decay was observed from the cervical to the apical post region; e) resin cement DC% was statistically similar at all points of measurements for both posts; and, f) BS: BDP = GFP, regardless the adhesive protocol used. It was concluded that: a) teeth restored with BDP exhibited lower fracture resistance than those restored with GFP; b) resin cement DC% was not influenced by the light transmitting ability of the post; c) the retention provided by the BDP was similar to the one provided by GFP, independently of the luting protocol.


Asunto(s)
Dentina , Fenómenos Mecánicos , Animales , Fenómenos Biomecánicos , Bovinos , Fenómenos Ópticos , Propiedades de Superficie
11.
J Mech Behav Biomed Mater ; 91: 398-405, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30669058

RESUMEN

Hydrolytic and enzymatic degradation by matrix metalloproteinases (MMPs) reduces the durability of composite resin restorations on caries-affected dentin (CAD). The use of MMP inhibitors such as epigallocatechin-3-gallate (EGCG) could increase the longevity of the bond to dentin. This study aimed to evaluate the use of EGCG at different aqueous concentrations on the resin-dentin microtensile bond strength (µTBS), fracture pattern and nanoleakage (NL) in immediate (IM) time interval and after 12-months of water storage (1Y) when using a two-step etch-and-rinse adhesive system on CAD. Dentin surfaces of 40 human molars were submitted to a microbiological caries induction protocol and randomized into 5 groups (n = 8) (0.02% EGCG; 0.2% EGCG; 0.5% EGCG; 2% Chlorhexidine [CHX] and no treatment as Control Group - [NT]). After acid etching, the solutions were applied for 60 s followed by application of dental adhesive (Adper Single Bond 2, 3 M ESPE) to CAD surfaces. Subsequently, a resin composite (4 mm) block was built on the dentin. After 24 h, the teeth were sectioned into beam-shaped specimens (cross-sectional area of 1 mm2 and 8-mm high). Half of the specimens were tested in IM and the other half after 1Y. Two samples per tooth were submitted to SEM for NL evaluation. Data were statistically analyzed by two-way ANOVA and Tukey tests (α = 0.05). The results showed that use of EGCG and CHX did not affect µTBS in IM (p > 0.05). After 1Y, there was a reduction in µTBS for all experimental groups (p < 0.05). Adhesive fractures predominated in IM in all groups, except for 0.05% EGCG and NT. After 1Y, there was an increase in these adhesive fractures in all groups. For NL, all agents applied reduced NL in comparison with CT (p < 0.001). CHX showed lower NL (p < 0.001), followed by 0.02% and 0.5% EGCG. NT showed highest NL for both time intervals (p < 0.001). Thus, although the use of EGCG at different concentrations and CHX reduced the NL, they were unable to reduce degradation of µTBS to CAD over time.


Asunto(s)
Catequina/análogos & derivados , Recubrimiento Dental Adhesivo , Caries Dental , Dentina/química , Dentina/efectos de los fármacos , Adhesividad/efectos de los fármacos , Catequina/química , Catequina/farmacología , Humanos , Soluciones , Factores de Tiempo
12.
Clin Cosmet Investig Dent ; 11: 383-392, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31908538

RESUMEN

Objective: The purpose of this single-blind (evaluators) and parallel design study was to evaluate whether exposure to a cola-based soft drink during bleaching treatment with 35% hydrogen peroxide (HP) affects color change and bleaching-induced tooth sensitivity. Material and methods: Forty-four patients with central incisors darker than A2 were selected. Participants who did not drink cola-based soft drinks were assigned to the control group (CG), while participants who drank a cola-based soft drink at least twice a day were assigned to the experimental group (EG). For the CG, foods with staining dyes were restricted. For the EG, there was no restriction on food and patients were asked to rinse their mouths with a cola-based soft drink for 30 s, 4 times daily. For both groups, 2 sessions with three 15 min applications of 35% HP were performed. Shade evaluation was assessed via subjective (VITA classical and VITA bleacheguide shade guides) and objective methods (Easyshade spectrophotometer) at baseline, during bleaching (first, second, and third weeks), and post bleaching (1 week and 1 month). Patients recorded their sensitivity perceptions using a numerical rating scale and 0-10 visual analog scales. Variation in shade guide units and the 2 colors (DE) were evaluated with a Student's t-test (α = 0.05) and Mann-Whitney test (α = 0.05). Absolute risk of tooth sensitivity and intensity of tooth sensitivity were evaluated by a Chi-square test (α=0.05). Results: Effective bleaching was observed for both groups after 30 days, without statistical difference (p > 0.08). There was no significant difference in absolute risk of bleaching-induced tooth sensitivity between the 2 groups (p = 0.74). Higher and significant scores in pain scales were detected for the EG in comparison to the CG (p < 0.05). Conclusion: Even that the cola-based soft drink exposure during in-office bleaching treatments did not affect the bleaching's effectiveness; patients reported a higher intensity in bleaching-induced tooth sensitivity.

13.
J Adhes Dent ; 20(5): 397-403, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30417895

RESUMEN

PURPOSE: To evaluate the immediate and 12-month microtensile bond strength (µTBS) of two self-etch adhesives on sclerotic dentin with or without previous EDTA conditioning. The conditioning pattern and the relative area of open dentinal tubules were also evaluated. MATERIALS AND METHODS: Twenty-eight bovine incisors with naturally exposed sclerotic dentin were used. For µTBS testing, 20 teeth were divided into 4 groups (n = 5) according to the combination of the main factors: 1. adhesive (Clearfil SE Bond [CSE, Kuraray] and Adper SE Plus [ADSE, 3M Oral Care]); 2. surface treatment (previous conditioning with EDTA and previous conditioning with distilled water [DW]). The sclerotic surfaces were conditioned with either 17% EDTA or DW for 2 min prior to adhesive application. Composite buildups were constructed. Specimens were sectioned to obtain composite-dentin sticks (0.8 mm2) to be tested immediately or after 12 months (distilled water at 37°C) in tensile mode (0.5 mm/min). The conditioning pattern and the relative area of open dentinal tubules (OT) were evaluated in the remaining eight teeth. After adhesive application, the surfaces were rinsed off with acetone and ethanol. Then the surface was evaluated by SEM with image software. Data from µTBS and OT were submitted to three-way repeated measures ANOVA and data from OT were submitted to one-way repeated measures ANOVA. After, for both tests, Tukey's post-hoc test was applied (α = 0.05). RESULTS: For both adhesives, EDTA resulted in the highest mean immediate µTBS (p = 0.002), which remained stable after 12 months of water storage (p < 0.38). CSE showed higher µTBS when compared to ADSE (p = 0.001). Degradation of the mean µTBS was observed for both adhesives only in the DW groups. Adhesive application plus with EDTA conditioning increased the OT area in comparison with only adhesive application (p < 0.001). CONCLUSION: EDTA conditioning increased the immediate microtensile bond strength in sclerotic dentin substrate and prevented degradation when associated with a self-etch adhesive.


Asunto(s)
Materiales Dentales/química , Dentina/efectos de los fármacos , Ácido Edético/química , Cementos de Resina/química , Animales , Bovinos , Análisis del Estrés Dental , Dentina/patología , Recubrimientos Dentinarios/química , Técnicas In Vitro , Incisivo , Ensayo de Materiales , Propiedades de Superficie , Resistencia a la Tracción
14.
J Adhes Dent ; 20(2): 121-132, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29675512

RESUMEN

PURPOSE: To evaluate the microtensile bond strength (µTBS) and nanoleakage (NL) of several universal adhesives to eroded dentin (ED), using etch-and-rinse (ER) or self-etch (SE) strategies, and to characterize the surface using two pH cycling models to erode dentin (citric acid and a soft drink). MATERIALS AND METHODS: Molars were eroded either by soft-drink or citric acid cycling, or were left untreated as control (SD). For each surface, the following adhesives were applied: 1. All-Bond Universal; 2. Ambar Universal; 3. Clearfil Universal; 4. Futurabond U; 5. One Coat 7 Universal; 6. Peak Universal Bond; 7. Prime&Bond Elect; 8. Scotchbond Universal; 9. Tetric n-bond Universal, and 10. Xeno Select. After application of the composite, specimens were sectioned into composite-dentin sticks and tested under tension (0.5 mm/min). Selected sticks from each tooth were used to assess NL. The occlusal dentin surfaces after erosive cycling were examined using SEM. Data were analyzed by three-way ANOVA and Tukey's post-hoc test (a = 0.05). RESULTS: In ED, there was no difference in µTBS and NL between ER and SE strategies (p > 0.61). Most µTBS and NL values obtained for ED were, respectively, lower and higher than those for SD (p < 0.01), being worse for citric acid ED (p < 0.001). Citric-acid-eroded dentin showed more enlarged tubules, with partial loss of peritubular dentin when compared to soft-drink eroded dentin. CONCLUSION: The different pH cycling models reduced µTBS and increased NL of the composite/eroded-dentin interface; however, in ED, the performance of the universal adhesives did not depend on the adhesive strategy used.


Asunto(s)
Recubrimiento Dental Adhesivo , Cementos Dentales , Resinas Compuestas , Dentina , Recubrimientos Dentinarios , Ensayo de Materiales , Cementos de Resina , Resistencia a la Tracción
15.
J Adhes Dent ; 20(1): 57-64, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29457156

RESUMEN

PURPOSE: To investigate the effect of Ca(OH)2 concentration on pH neutralization, degree of conversion (DC%), and bonding performance of experimental self-etch adhesives (SEAs). MATERIALS AND METHODS: Four different concentrations of Ca(OH)2 (0 wt%, 1 wt%, 2 wt%, and 4 wt%) were added to the bond of an experimental two-step SEA consisting of primer (10-MDP [30 wt%], TEG-DMA [30 wt%], ethanol [35 wt%], water [5 wt%], camphorquinone [0.5 wt%], and tertiary amine [0.5 wt%]) and bond (bis-GMA [50 wt%], TEG-DMA [30 wt%], HEMA [20 wt%], camphorquinone [0.5 wt%], and tertiary amine [0.5 wt%]) to form four groups: E0, E1, E2 and E4. pH neutralization was evaluated until it reached equilibrium, and DC% within the hybrid layer was analyzed by micro-Raman spectroscopy. Human molars were wet ground until the occlusal dentin was exposed, SEAs were applied, and composite buildups were constructed. After storage in distilled water at 37°C for 24 h, the teeth were cut into composite-dentin beams. Microtensile bond strength (µTBS) was evaluated after 24 h of water storage at 37°C. Nanoleakage was evaluated by SEM. Data were analyzed using ANOVA and Tukey's HSD test (a = 0.05). RESULTS: All the SEAs reached pH equilibrium after thirteen days, with E1 and E4 presenting the highest pH (p < 0.05). E0 and E1 presented lower DC% than did E2 and E4 (p < 0.05). All the SEAs showed statistically similar mTBS and nanoleakage (p > 0.05). CONCLUSION: The incorporation of Ca(OH)2 endowed the SEAs with pH-neutralization ability and improved their DC%, without interfering with the bond strength to dentin or nanoleakage extent.


Asunto(s)
Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios , Hidróxido de Calcio , Resinas Compuestas , Cementos Dentales , Dentina , Humanos , Ensayo de Materiales , Metacrilatos , Cementos de Resina , Resistencia a la Tracción , Agua
16.
Rev. bras. cancerol ; 64(1): 93-98, Jan/Fev/Mar 2018.
Artículo en Portugués | LILACS | ID: biblio-969213

RESUMEN

Introdução: Bisfosfonatos são fármacos utilizados para o tratamento de enfermidades ósseas, como a osteoporose e metástases ósseas, em razão do seu mecanismo de ação, que consiste na diminuição do processo de reabsorção do osso. Outros estudos verificaram que bisfosfonatos de alta potência, como o zoledronato, poderiam auxiliar no tratamento de outras enfermidades malignas por causa da promoção de um efeito antiproliferativo. Objetivo: Este estudo in vitro objetivou avaliar a atividade antiproliferativa de zoledronato em diferentes linhagens de células tumorais. Método: Nove linhagens humanas (U251; MCF7; NCI/ADR-RES; 786-0; NCI-H460; PC-3; OVCAR-3; HT29; K-562 e HaCaT) foram submetidas ao tratamento com as concentrações de 0,12; 1,2; 12 e 120 µM de zoledronato e tiveram sua atividade proliferativa avaliada após 48 horas, utilizando-se o corante sulforrodamina B. Resultados: Verificou-se que as concentrações de 12 µM e 120 µM de zoledronato foram eficazes para a redução em 50% e 100%, respectivamente, da proliferação das células 786-0 (carcinoma renal). A maior concentração de zoledronato (120 µM) promoveu um efeito citostático (redução da proliferação celular em 50%) para as células HaCaT (queratinócito humano não tumoral), HT-29 (carcinoma de cólon), NCI-ADR/ RES (adenocarcinoma de ovário com fenótipo de multirresistência) e NCI-H460 (carcinoma pulmonar). Conclusão: Esses resultados sugerem um promissor efeito auxiliar do zoledronato para o tratamento de alguns tipos de tumores; estudos complementares in vitro e in vivo são necessários para a validação dessa hipótese.


Introduction: Bisphosphonates are used in the treatment of bone diseases such as osteoporosis and bone metastases, because of their ability to inhibit bone resorption. There is evidence that high-potency bisphosphonates, such as zoledronate, are useful in the treatment of other malignancies because they have an antiproliferative effect. Objective:To evaluate the antiproliferative activity of zoledronate in different tumor cell lines. Method: This was an in vitro study in which nine human cell lines (U251, MCF7, NCI/ ADR-RES, 786-0, NCI-H460, PC-3, OVCAR-3, HT29, K-562, and HaCaT) were treated with of 0.12, 1.2, 12, and 120 µM of zoledronate, their proliferative activity being evaluated 48 h later with sulforhodamine B assay. Results: At the 12 µM and 120 µM doses, zoledronate effectively reduced the proliferation of 786-0 (renal carcinoma) cells by 50% and 100%, respectively. At the highest concentration (120 µM), zoledronate had a cytostatic effect (50% reduction in cell proliferation) on HaCaT (non-tumor human keratinocyte), HT-29 (colon carcinoma), NCI-ADR/ RES (multidrug-resistant ovarian adenocarcinoma), and NCI-H460 (lung carcinoma) cells. Conclusion: These results suggest a promising auxiliary effect of zoledronate for the treatment of some tumors. Further in vitro and in vivo studies are needed in order to test that hypothesis.


Introducción: Los bisfosfonatos son fármacos utilizados para el tratamiento de enfermedades óseas, como la osteoporosis y metástasis óseas debido a su mecanismo de acción, que consiste en la disminución del proceso de reabsorción del hueso. Otros estudios observaron que los bisfosfonatos de alta potencia, como el zoledronato, podrían ayudar en el tratamiento de otras enfermedades malignas debido a la promoción de un efecto antiproliferativo. Objetivo: Este estudio in vitro objetivó evaluar la actividad antiproliferativa de zoledronato en diferentes linajes de células tumorales. Método: Los nueve humano linajes (U251, MCF7, NCI / ADR-RES, 786-0, NCI-H460, PC-3, OVCAR-3, HT29, K-562 and HaCaT) se sometieron al tratamiento con las concentraciones de 0,12; 1,2; 12 y 120 µM de zoledronato y tuvieron su actividad proliferativa evaluada después de 48 horas utilizando el colorante sulforrodamina B. Resultados: Se comprobó que las concentraciones de 12 µM y 120 µM de zoledronato fueron efectivas para reducir en un 50% y un 100%, respectivamente, de la proliferación de las células 786-0 (carcinoma renal). La mayor concentración de zoledronato (120 µM) promovió un efecto citostático (reducción de la proliferación celular en un 50%) para las células HaCaT (queratinocito humano no tumoral), HT-29 (carcinoma de colon), NCI-ADR/RES (adenocarcinoma de ovário con fenótipo de multirresistencia) y NCI-H460 (carcinoma pulmonar). Conclusión: Estos resultados sugieren un prometedor efecto auxiliar del zoledronato para el tratamiento de algunos tumores; se requieren más estudios in vitro e in vivo para validar esta hipótesis


Asunto(s)
Humanos , Proliferación Celular/efectos de los fármacos , Difosfonatos , Técnicas In Vitro , Células Tumorales Cultivadas/efectos de los fármacos , Línea Celular Tumoral/efectos de los fármacos
17.
J Dent ; 68: 91-97, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29169968

RESUMEN

OBJECTIVE: This randomized double-blind clinical trial compared tooth sensitivity (TS), bleaching efficacy, and cytokine levels after applying in-office bleaching treatments containing 15% and 35% hydrogen peroxide (HP15% and HP35%, respectively). METHODS: Twenty-five volunteers were randomly assigned to receive HP15% or HP35% treatment. The bleaching agent was applied in three 15-min applications per session. Two bleaching sessions were separated by a 1-week interval. The participants scored TS using a visual analog scale and numerical rating scale. Bleaching efficacy was determined by subjective and objective methods. Gingival crevicular fluid was collected from three jaws sites per patient for the analysis of fluid volume. Flow cytometry was used to analyze gingival crevicular fluid levels of interleukin (IL)-1ß, IL-2, IL-4, IL-6, IL-10, tumor necrosis factor, and interferon-gamma. All measurements were obtained before and after bleaching. All data were statistically analyzed (α=0.05). RESULTS: The absolute risk and intensity of TS was higher for HP35% than for HP15% (p>0.002). One month post-bleaching, HP35% produced more bleaching than HP15% (p=0.02). However patient perception (p=0.06) and patient satisfaction (p=0.53) with regard to bleaching were not significantly different. No significant differences existed in the gingival fluid volume (p>0.38) or in any cytokine level (p>0.05) for either HP concentration. CONCLUSION: Treatment: with HP35% is more effective than HP15%, but generates a greater risk and intensity of TS. No inflammatory changes occurred despite the difference in the HP concentrations. CLINICAL SIGNIFICANCE: Hydrogen peroxide at a lower concentration (e.g., 15%) should be considered a good treatment alternative for in-office bleaching because the higher concentration for in-office bleaching generates a greater risk and intensity of TS for patients.


Asunto(s)
Sensibilidad de la Dentina/etiología , Líquido del Surco Gingival/química , Peróxido de Hidrógeno/efectos adversos , Blanqueadores Dentales/efectos adversos , Blanqueamiento de Dientes/efectos adversos , Adolescente , Adulto , Análisis de Varianza , Citocinas/análisis , Método Doble Ciego , Encía/efectos de los fármacos , Humanos , Peróxido de Hidrógeno/administración & dosificación , Luz/efectos adversos , Satisfacción del Paciente , Blanqueadores Dentales/administración & dosificación , Decoloración de Dientes/terapia , Resultado del Tratamiento , Escala Visual Analógica , Voluntarios , Adulto Joven
18.
J Adhes Dent ; 19(6): 497-505, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29234755

RESUMEN

PURPOSE: To compare the enamel bonding performace of two commercial and three experimental two-step self-etch adhesives containing acidic functional monomers with different carbon-spacer length and hydrophilicity. The contact angle was also assessed to evaluate the wettability of each tested material. MATERIALS AND METHODS: Forty extracted human molars were sectioned into four parts (buccal, lingual, mesial, and distal) and divided into 5 groups, according to the adhesives used: Clearfil SE Bond (CSE), AdheSE (ADSE), 10-MDP (15 mol% 10-methacryloyldecylphosphate), CAP-P (15 mol% caprolactone phosphate), and MTEP (15 mol% methacryloyltetraethylene phosphate). Enamel specimens were bonded with each adhesive and submitted to microshear bond strength (µSBS) testing after 24 h. The adhesives were applied onto additional enamel specimens without light curing to assess contact angle. Then the etching pattern was analyzed using SEM and confocal laser scanning microscopy (CLSM). The µSBS and contact angle data were analyzed by one-way ANOVA and Tukey's test (α = 0.05). RESULTS: 10-MDP showed the highest µSBS of the tested groups (p < 0.05), followed by CAP-P and CSE (p < 0.05). MTEP and ADSE exhibited the lowest µSBS (p < 0.05), but the difference between them was not significant. 10-MDP, CSE, and CAP-P exhibited lower contact angles (p < 0.05) than did ADSE and MTEP. The SEM and CLSM analyses showed that 10-MDP and CSE had the most pronounced etching patterns and deepest adhesive penetration. ADSE and MTEP exhibited weak etching ability and adhesive penetration, while CAP-P produced moderate etching and intermediate penetration. CONCLUSIONS: The length and hydrophilicity of the functional monomer spacer chain tested in this study influenced the enamel bonding performance. Functional monomers with longer chains and more hydrophobic properties, such as 10-MDP and CAP-P, may interact better with enamel and achieve higher enamel bond strength.


Asunto(s)
Grabado Ácido Dental , Recubrimiento Dental Adhesivo , Carbono , Resinas Compuestas , Cementos Dentales , Esmalte Dental , Recubrimientos Dentinarios , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Cementos de Resina
19.
J Adhes Dent ; 19(3): 203-212, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28580465

RESUMEN

PURPOSE: To evaluate the effect of a silane and an adhesive containing MDP, used alone or combined in the same solution, on the microshear bond strength (µSBS) to lithium disilicate ceramics immediately and after 1-year water storage, and compare the bond strength results with the Raman spectra of the treated lithium disilicate surfaces. MATERIALS AND METHODS: A total of 30 CAD/CAM blocks of lithium disilicate (LD; IPS e.max CAD) were cut into four square sections (6 x 6 x 6 mm; n = 60 per group) and processed as recommended by the manufacturer. The LD specimens were divided into 12 groups according to the following independent variables: silane coupling agent (no silane; silane without 10-MDP [MBS, Monobond S]; silane with 10-MDP [MB+, Monobond Plus]) and adhesive + luting composite (no adhesive + Enforce; no adhesive + RelyX Ultimate; Prime & Bond Elect [PBE], a silane- and MDP-free universal adhesive + Enforce; Scotchbond Universal Adhesive [SBU], a silane- and MDP-containing universal adhesive + RelyX Ultimate). After each treatment, cylindrical, transparent matrices were filled with a luting composite and light cured. Specimens were stored in water (37°C for 24 h or 1 year) and submitted to the microshear bond strength (µSBS) test. The failure pattern and µSBS were statistically evaluated (α = 0.05). In addition, specimens were examined for chemical interaction using Raman spectroscopy. RESULTS: The use of the adhesive PBE alone showed higher mean µSBS compared with both groups with silane (MSB or MB+) without PBE (p < 0.001) at 24 h. The use of the SBU adhesive or MBS silane alone, as well as MB+ associated with SBU, showed higher mean µSBS (p < 0.001) at 24 h. After 1-year water storage, all groups showed a significant decrease in mean µSBS. However, the application of PBE or SBU associated with MB+ silane showed higher 1-year mean µSBS (p < 0.001). In terms of chemical interaction, when silane (MSB or MB+) was applied, only a slight decrease of Si-O peaks occurred. Otherwise, when PBE or SBU adhesives were applied, methacrylate peaks were only observed in the SBU groups. CONCLUSION: The best results in terms of bond strength after water storage were obtained when an MDP-containing silane was associated with a universal adhesive. The use of a simplified bonding protocol that includes either a silane or a universal adhesive is not recommended.


Asunto(s)
Recubrimiento Dental Adhesivo , Silanos , Cerámica , Porcelana Dental , Ensayo de Materiales , Resistencia al Corte
20.
J Adhes Dent ; : 195-201, 2017 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-28597005

RESUMEN

PURPOSE: To evaluate the effect of three phosphoric acids modified with chlorhexidine (CHX), benzalkonium chloride (BAC), or proanthocyanidins (PRO) and one conventional phosphoric acid (CON) on the immediate (24 h; IM) and 1-year composite-dentin microtensile bond strength (µTBS) and nanoleakage (NL), using an etch-and-rinse adhesive. MATERIALS AND METHODS: A flat dentin surface was exposed on 28 caries-free extracted molars, which were then randomly assigned to four groups (n = 7). After etching and rinsing with one phosphoric acid per group, the adhesive (Adper Single Bond 2) was applied on a moist dentin surface. Composite buildups (Filtek Z350) were constructed incrementally and bonded stick specimens (0.8 mm2) were prepared and submitted to the microtensile test (0.5 mm/min) immediately (24 h) or after 1 year of water storage. For nanoleakage, 2 bonded sticks from each tooth at each storage period were immersed in 50 wt% ammoniacal silver nitrate, polished, and analyzed by SEM in backscattered mode. Data were submitted to a two-way ANOVA and Tukey's test (α = 0.05). RESULTS: After 1 year, stable µTBS values were observed only for the modified phosphoric acids (CHX, BAC, and PRO). Also, NL was more evident in the CON group than in the CHX, BAC and PRO groups (p < 0.05) after 1-year water storage. CONCLUSIONS: Compared to the control, the phosphoric acid etchants which contained protease inhibitors (CHX, BAC and PA) promoted the stability of composite-dentin microtensile bond strength and showed less nanoleakage after 1 year of water storage. They represent an effective way of prolonging the stability of the composite-dentin bonds without creating an additional bonding step.

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