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1.
J Contemp Dent Pract ; 21(1): 91-96, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32381808

RESUMO

AIM: The aim of this study was to assess if the curing mode and the etching mode could affect the push-out bond strength of different post cementation systems using two universal adhesives. MATERIALS AND METHODS: A total of 100 single-rooted teeth were divided into Prime & Bond Elect (PBE), Prime & Bond Active (PBA), and Prime & Bond XP (PBXP) as a control. The PBE, PBA, and PBXP were used in the self-etch (SE) and etch and rinse (E&R) mode. Post cementation was performed using Core X flow used in dark-cure and in light-cure. Data were analyzed using the one-way ANOVA test and post hoc Bonferroni and Dunnet tests. The Student's t test was performed to find significance between two independent groups. RESULTS: Bond strength was significantly influenced by the adhesive strategies. The PBE and PBA obtained higher values when used in the SE mode (p < 0.001). Light-cured groups obtained significantly higher values (p < 0.001) compared to dark-cured groups. The post space region also had a significant effect on the bond strength; the apical third recorded lower values in all groups (p < 0.001). CONCLUSION: The PBA and PBE universal adhesives obtained higher PBS values when used in the SE mode and followed by the light-curing of resin cement. CLINICAL SIGNIFICANCE: Universal adhesives represent a good alternative to the conventional total-etch adhesive system for fiber post cementation. Since they perform better in SE, they would be recommendable in clinical practice, as they can be used with a simplified technique.


Assuntos
Colagem Dentária , Adesivos Dentinários , Cimentos Dentários , Dentina , Humanos , Cimentos de Resina
2.
Indian J Dent Res ; 31(2): 236-240, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32436903

RESUMO

Aims: Considering new ceramic systems, doubts about the appropriate combination of ceramics and cement are common. Settings and Design: To evaluate the influence of the elastic modulus (E) of cement agents associated with different indirect veneers on the stress distribution using finite element analysis. Methods and Materials: The finite element analysis was applied to evaluate the stress distribution on the structures. For that, a computer-aided design software was used for a three-dimensional (3D) modeling of an upper central incisor with preparation for an indirect veneer. The model was imported into the analysis software in STEP (Standard for Exchange of Product data) format. Tetrahedral elements formed the mesh. Solids were considered isotropic, linearly elastic, homogeneous, and with ideal contacts. Load application (100N, 45°) occurred on the lingual face. Cement agents have their E classified as low, intermediate, and high. The ceramic materials used were a hybrid ceramic, a zirconia reinforced lithium silicate and a lithium disilicate. Results: It was observed that none of the factors significantly influenced the stress concentration in dentine. Groups with high E cementing agent showed the highest stress peaks. The E of restorative material was significant for the stress generated in the veneer, and groups with hybrid ceramic presented more homogeneous stress results. Conclusions: The higher E of the cement agent and the ceramic, the higher the stress concentration, suggesting that hybrid ceramic associated with low elastic modulus resinous cement has superior biomechanical behavior.


Assuntos
Porcelana Dentária , Incisivo , Cerâmica , Cimentos Dentários , Materiais Dentários , Análise do Estresse Dentário , Análise de Elementos Finitos , Teste de Materiais , Estresse Mecânico
3.
Indian J Dent Res ; 31(2): 291-296, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32436911

RESUMO

Context: In-vitro studies of microleakage are an initial screening method to assess the maximum theoretical loss of sealing ability in-vivo. Aims: Our objective was to determine and compare microleakage patterns of conventional glass ionomer cement (GIC) and resin-modified GIC (RMGIC) for band cementation. Methods: Forty caries-free second primary molars were randomly divided into two groups of 20 teeth each. Preformed molar bands in the two groups were cemented to enamel with one of two types of cement: Conventional GIC (Fuji I, GC Corporation; Tokyo, Japan) and RMGIC (Fuji Plus, GC Corporation; Tokyo, Japan). A dye penetration method was used for microleakage evaluation. Microleakage was determined by a stereomicroscope for the cement-band and cement-enamel interfaces. Statistical Analysis Used: Statistical analysis was performed with Kruskal-Wallis and Mann-Whitney U tests. Results: The mean microleakage value for conventional GIC (Fuji I) at cement-band and cement-enamel interfaces was 2.41 mm and 2.15 mm, respectively. The mean microleakage value for RMGIC (Fuji Plus) at cement-band and cement-enamel interfaces was 0.44 mm and 0.46 mm, respectively. Compared to conventional GIC, RMGIC showed less microleakage at both cement-band and cement-enamel interfaces. P < 0.001 and it was statistically highly significant. Conclusions: Bands cemented with RMGIC had significantly less microleakage between the cement-band and cement-enamel interfaces than conventional GIC.


Assuntos
Infiltração Dentária , Cimentos Dentários , Esmalte Dentário , Cimentos de Ionômeros de Vidro , Humanos , Cimentos de Resina , Dente Decíduo
4.
Stomatologiia (Mosk) ; 99(2): 17-20, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32441070

RESUMO

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


Assuntos
Colagem Dentária , Condicionamento Ácido do Dente , Resinas Compostas , Cimentos Dentários , Análise do Estresse Dentário , Humanos , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento , Propriedades de Superfície
5.
J Contemp Dent Pract ; 21(3): 220-226, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32434964

RESUMO

AIM: The aim of this research was to determine whether sterilization and reutilization of impression copings had an impact on the accuracy of casts made for multiimplant restorations. MATERIALS AND METHODS: Four master casts embedded with five implant analogs were fabricated. Polyvinyl siloxane (PVS) impressions of the master cast with copings attached to the analogs were made and poured in dental stone. The impression copings were subjected to cleaning and sterilization. These processes were repeated 30 cycles for each of the two groups of five impression copings: one without modification and one with modification that included air abrasion and PVS adhesive. A coordinate measuring machine (CMM) was used to measure relative angles and distances between the reference analog and analogs. The relative angles and distances measured on the stone casts were compared to the master resin cast to obtain positional and angular displacements. RESULTS: For impression copings that were not modified, a significant difference was detected for both positional and angular displacements. For impression copings that were modified, a significant change was observed only for positional displacement. The maximum discrepancies measured for positional and angular displacements after 30 cycles of reuse were only 81 µm and 0.46°, respectively, regardless of the modification. CONCLUSION: Within the limitations of this study, unmodified impression copings that have undergone 30 cycles of cleaning and sterilization appeared to incur more impression inaccuracy than those impression copings that were modified by airborne-particle abrasion and PVS adhesive. CLINICAL SIGNIFICANCE: Impression copings used in this study can likely be recycled up to 30 times without reducing the accuracy of the impression to a level that may be considered clinically significant.


Assuntos
Materiais para Moldagem Odontológica , Técnica de Moldagem Odontológica , Adaptação Psicológica , Abrasão Dental por Ar , Cimentos Dentários , Modelos Dentários , Propriedades de Superfície
6.
J Adhes Dent ; 22(3): 255-264, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32435766

RESUMO

PURPOSE: To evaluate the influence of application protocol on the shear bond strength (SBS) and nanoleakage of simplified adhesives over 18 months. MATERIALS AND METHODS: 810 dentin slices were obtained from 405 caries-free human molars. They were randomly assigned to 54 experimental groups resulting from the combination of "adhesive" (Adper Scotchbond 1XT [S1XT], Solobond M [SM], Scotchbond Universal Adhesive in etch-and-rinse mode [SUER] and self-etch mode [SUSE], Adper Easy Bond [EB], Clearfil S3 Bond Plus [CS3]), "application protocol" (manufacturer's instructions [MI], two extra layers of adhesive [EL], hydrophobic resin layer [HL]), and "aging time" (24 h [24H], 6 months [6M], and 18 months [18M] in water). SBS tests were carried out using a Watanabe device followed by failure mode analysis. For the nanoleakage study, specimens from 54 additional molars were prepared as previously described, immersed in ammoniacal silver nitrate, and evaluated with SEM. SBS data were analyzed with ANOVA followed by Tukey's post-hoc tests; failure mode data were analyzed using chi-squared tests (α = 0.05). Nanoleakage data were analyzed with the Kruskal-Wallis test followed by LSD tests (α = 0.05). RESULTS: After 18M, S1XT and SUSE achieved the highest mean SBS (p < 0.05). Regarding the application protocols, EL and HL provided higher mean SBS than those obtained with MI (p < 0.05). HL resulted in the highest mean SBS and the lowest mean nanoleakage after 18M. CONCLUSION: Simplified adhesives may need an extra hydrophobic resin layer to achieve a stable and durable adhesive interface. The self-etch approach should be recommended for the universal adhesive.


Assuntos
Colagem Dentária , Cimentos Dentários , Dentina , Humanos , Teste de Materiais , Resistência ao Cisalhamento
7.
J Adhes Dent ; 22(3): 265-274, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32435767

RESUMO

PURPOSE: To investigate whether dental adhesives modified with polyacrylic acid copper iodide particles could inhibit esterase activity in vitro and the copper release rate from resin matrices, as well as the correlation between the two variables. MATERIALS AND METHODS: Different concentrations of copper iodide (0.1, 0.5 and 1.0 mg/ml) were incorporated into three commercially available adhesives representative of each type. Disk specimens (n = 3) were fabricated and incubated in cholesterol esterase and pseudo-cholinesterase solutions for 16 days (37°C, pH 7.0). The enzymatic activity and rate of copper release from resin matrices were evaluated at different 4, 8, 12, and 16 days with a UV/visible-light spectrophotometer. RESULTS: Increased copper release and reduced enzymatic activity were observed with higher concentrations of copper iodide (p < 0.001). Greater copper release with reduced enzymatic activity was also demonstrated at the earlier time periods with this relationship reversing over time (p < 0.001). A moderate negative correlation between the variables was evident (-0.441; p = 0.01). CONCLUSIONS: Adhesives containing copper iodide can inhibit esterase activity in a dose- and time-dependent manner. The correlation between the variables suggests that enzymatic activity may depend on the availability of copper.


Assuntos
Cimentos Dentários , Iodetos , Cobre , Esterases , Teste de Materiais
8.
J Adhes Dent ; 22(3): 285-296, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32435769

RESUMO

PURPOSE: To investigate the long-term effect of 0.05% or 0.1% caffeic acid phenethyl ester (CAPE) on dentin matrix stability and hybrid layer stability, using an etch-and-rinse (Adper Scotchbond Multipurpose/ASB) or a self-etch adhesive (Clearfil SE Bond/CSE). MATERIALS AND METHODS: Dentin matrix specimens were assigned to five groups: 0.05% or 0.1% CAPE, green tea (GT), and the controls distilled water (DW) and dimethyl sulfoxide (DMSO). Following immersion of specimens for 1 h, modulus of elasticity (ME) and dentin mass change (MG) were determined at 3 post-treatment time points: immediately afterwards and at 3 and 6 months. Collagen solubilization (CS) was estimated by hydroxyproline (HYP) quantification. Resin-dentin interfaces with both adhesives were assessed with in situ zymography tests to evaluate gelatinolytic activity (GA). The dentin pretreatments were actively applied for 60 s. The sealing ability of aged resin-bonded slices was assessed by nanoleakage tests. RESULTS: GT increased immediate ME, which decreased significantly after 3 months (p < 0.0001). The CAPE groups did not differ from the control groups. GT provided a significant increase in dentin matrix mass after treatment (p < 0.0001). No significant differences regarding MG were observed for CAPE 0.1%, CAPE 0.05%, DW, and DMSO groups after 3 and 6 months. Cumulative HYP release revealed that CAPE groups and GT were statistically similar to DW and DMSO; the GT group exhibited statistically significantly less HYP release than did CAPE groups (p = 0.0073). Treatment with 0.05% or 0.1% CAPE presented lower GA when applied to ASB before acid conditioning (p < 0.05), but no differences were detected when the CAPE groups were applied to CSE. CAPE at 0.1% significantly reduced nanoleakage for CSE, and 0.05% CAPE with CSE presented levels of nanoleakage similar to those of the CSE control group. CONCLUSION: CAPE at 0.05% or 0.01% did not influence ME, MG, or CS, but reduced GA when applied to ASB before acid conditioning. CAPE at 0.1% with CSE promoted adhesive layer integrity.


Assuntos
Colagem Dentária , Adesivos Dentinários , Ácidos Cafeicos , Cimentos Dentários , Dentina , Teste de Materiais , Álcool Feniletílico/análogos & derivados , Resistência à Tração
9.
J Adhes Dent ; 22(3): 297-309, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32435770

RESUMO

PURPOSE: To evaluate the remineralization effects of Bioglass 45S5 (BAG) on dentin composition, adhesive-dentin bond strength, as well as interface and diffusion zone thickness. MATERIALS AND METHODS: Dentin specimens were assigned to a control group (CG), in which the adhesive was applied following the manufacturer's instructions, and a remineralized group (RG), in which remineralization treatment was carried out by rubbing a remineralization solution (0.015 g of BAG with 1.35 ml of distilled water) on the etched dentin surface for 30 s before applying the adhesive. For bioactive analysis (n = 10), control and remineralized dentin were investigated using micro-Raman spectroscopy (mRS) and scanning electron microscopy (SEM). Stick specimens prepared with a three-step etch-and-rinse adhesive were submitted to a microtensile bond strength (µTBS) test (n = 10) after 24 h (24 h) and eight months (8 m). Micro-RS 3D-maps (n = 10) characterized the adhesive-dentin interface composition and diffusion zone thickness, and SEM images (n = 10) evaluated interface thickness. Data were analyzed using Student's t-test or two-way ANOVA and Tukey-Kramer's post-hoc test (α = 0.05). RESULTS: Remineralization treatment increased the mineral content of dentin. Mean µTBSs were statistically different at 24 h, with RG higher than CG; however, this difference was not significant at 8 m. When the adhesive was applied on remineralized dentin, its penetration was reduced, its physical interaction with phosphate was improved, and its degree of conversion increased. The diffusion zone in the CG did not differ from that of the RG, and interface thickness values of the CG did not differ from that of the RG. CONCLUSION: Remineralization treatment promoted mineral growth on the dentin surface, improved the interaction of dentin with adhesive monomers, and consequently resulted in higher immediate bond strengths.


Assuntos
Colagem Dentária , Cimentos Dentários , Dentina , Adesivos Dentinários , Humanos , Resistência à Tração
10.
Quintessence Int ; 51(5): 398-404, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32253391

RESUMO

OBJECTIVE: To describe and illustrate the histologic characteristics of luting cement-induced peri-implantitis in the posterior maxilla of a 56-year-old man. CASE PRESENTATION: A dental implant inserted 6 years previously in the maxillary left first premolar region revealed pus and swelling. A periapical radiograph showed severe bone loss around the dental implant, and the presence of surrounding residual particles of luting cement. The implant was removed with its adjacent tissues. The harvested implant was fixed in formaldehyde solution (formalin). A 4-mm fragment of soft tissue and a 6-mm fragment of bone were cut from the implant specimen and submitted for routine processing of hematoxylin-eosin (h&e) slides for histologic analysis. The implant specimen was processed and embedded in glycol methacrylate resin and ground to a thickness of 50 µm for histologic examination. RESULTS: The microscopic examination of the h&e slides showed connective tissue with an inflammatory infiltrate composed of histiocytes, lymphocytes, and plasma cells. There was a fragment of viable bone integrated with the bone graft material. The bone showed evidence of active resorption by osteoclasts in Howship lacunae. The implant sections showed trabecular bone with lamellar structure in the apical portion. Foreign body, compatible with luting cement, was present in the coronal portion, adjacent to the threads of the implant, as well as osteoclasts in Howship lacunae. CONCLUSION: This report, documenting a case of peri-implantitis associated with excess cement extrusion, revealed that that the bone loss was associated with an inflammatory infiltrate. Additional studies focusing on the histopathologic characteristics of peri-implantitis could help to increase the knowledge of peri-implant disease to shed light on prevention and treatment.


Assuntos
Implantes Dentários , Peri-Implantite , Cimentos Dentários , Materiais Dentários , Humanos , Masculino , Maxila , Pessoa de Meia-Idade
11.
J Adhes Dent ; 22(2): 161-172, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32322837

RESUMO

PURPOSE: To evaluate 1. the microtensile bond strength (µTBS) and in situ degree of conversion (DC) of adhesives applied using two bonding strategies after silver diamine fluoride (diamine) application on carious dentinal lesions, and 2. dentin etching patterns using SEM and energy dispersive x-ray spectroscopy. MATERIALS AND METHODS: Human molars were randomly divided into 12 experimental groups according to: 1. application of a silver diamine fluoride solution (carious dentinal lesion without silver diamine fluoride treatment [control], with 12% silver diamine fluoride [diamine 12%] or 38% silver diamine fluoride [diamine 38%]); 2. adhesives (Clearfil Universal Bond Quick [CUQ] and Scotchbond Universal [SBU]); 3. adhesive strategy (etch-and-rinse [ER] and self-etch [SE]). After restoration, the specimens were sectioned and submitted to µTBS testing. Sticks from each tooth were used for DC evaluation. To examine the changes induced by diamine before and after phosphoric acid treatment, SEM/EDX analysis was performed. Data from the µTBS and DC tests were analyzed using three-way ANOVA and Tukey's test (α = 0.05). RESULTS: Both concentrations of diamine resulted in a statistically significantly higher mean µTBS compared to the control (p < 0.0001). Diamine 38% showed a statistically significantly higher mean µTBS for both adhesives in SE mode compared to diamine 12% (p < 0.0001). The application of diamine to carious dentinal lesions did not significantly influence the mean DC values for either adhesive (p = 0.72). SBU showed a higher mean DC compared to CUQ (p = 0.03). After diamine treatment, there was an increase in the Ca peak intensity and the presence of residual silver ions mainly when diamine 38% was applied along with the SE approach. CONCLUSION: Independent of the adhesive application approach, the use of diamine may be a promising alternative to increase µTBS without jeopardizing the DC of the two adhesives in carious dentinal lesions.


Assuntos
Colagem Dentária , Cimentos Dentários , Dentina , Fluoretos Tópicos , Humanos , Compostos de Amônio Quaternário , Compostos de Prata , Resistência à Tração
12.
J Adhes Dent ; 22(2): 183-193, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32322839

RESUMO

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


Assuntos
Colagem Dentária , Condicionamento Ácido do Dente , Cimentos Dentários , Teste de Materiais
13.
J Adhes Dent ; 22(2): 195-204, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32322840

RESUMO

PURPOSE: To evaluate the effect of surface treatments and aging on the bond strength of composite cement to a novel CAD/CAM nanohybrid composite. MATERIALS AND METHODS: Microtensile bond strength (µTBS) of a dual-curing composite cement (Bifix QM; BQ) to three CAD/CAM restorative materials (Grandio [GR], Vita Enamic [VE], and Lava Ultimate [LU]) was evaluated after different surface treatments. The surfaces of specimens received the following treatments: control (no treatment), sandblasting (SB), SB + silane (Ceramic Bond; CB), hydrofluoric acid (HF), HF + CB, TiF4 2 wt/v%, TiF4 2 wt/v% + CB, TiF4 4 wt/v%, and TiF4 4 wt/v% + CB. Half of the specimens in each group were aged. Surface topography and surface roughness were evaluated. Statistical analysis was conducted using ANOVA and Tukey's test. The Weibull analysis was conducted on µTBS data of aged groups. RESULTS: The µTBS was significantly affected by the type of CAD/CAM material, type of treatment, and aging (p < 0.001). Silane application significantly improved the µTBS (p < 0.05). The µTBS decreased significantly with aging (5000 thermocycles) (p < 0.05). BQ cement resulted in the highest µTBS to GR treated with TiF4 2% wt/v + CB compared to the other groups (p < 0.05). Aged GR/BQ treated with TiF4 2% wt/v + CB had the highest predicted µTBS (19 MPa). CONCLUSION: TiF4 2% wt/v followed by silane application enhanced the adhesion of GR/BQ and LU/BQ systems. On the other hand, HF surface treatment followed by silane application improved the adhesion of the VE/BQ system.


Assuntos
Colagem Dentária , Cimentos de Resina , Cimentos Dentários , Teste de Materiais , Propriedades de Superfície
14.
J Adhes Dent ; 22(2): 207-214, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32322841

RESUMO

PURPOSE: To synthesize tantalum oxide quantum dots (Ta2O5QDs) using an imidazolium ionic liquid as a precursor and evaluate the effect of its addition to an experimental adhesive resin on the degree of conversion (DC) and antibacterial activity. MATERIALS AND METHODS: Ta2O5QDs was synthesized from the hydrolysis of an imidazolium ionic liquid (1-n-decyl-3-methylimidazolium hexachlorotantalate [DMI.TaCl6]) and evaluated by transmission electron microscopy (TEM). The adhesive was formulated with 66.7 wt% bisphenol A-glycidyl methacrylate (bis-GMA), 33.3 wt% 2-hydroxyethyl methacrylate (HEMA) with a photoinitiator/co-initiator system. In one group, Ta2O5QDS was added to the adhesive at 1 wt% Ta2O5QDs) and one group remained without Ta2O5QDS as control (CTRL). The adhesives were evaluated for DC by Fourier Transform Infrared spectroscopy. Direct contact inhibition assay was used to evaluate the antibacterial activity of the experimental adhesive resins against biofilm formation and planktonic bacteria. RESULTS: Ta2O5QDs had a particle size distribution of 1.52 ± 0.73 nm. DC was 50.91 ± 4.94% for CTRL and 55.4 ± 4.58% for Ta2O5QDs (p = 0.310). Ta2O5QDs showed less Streptococcus mutans biofilm formation on adhesive surfaces (p = 0.013). There was no statistically significant difference in terms of antibacterial activity against planktonic bacteria (p = 0.079). CONCLUSION: Non-agglomerated Ta2O5QDs synthesized from an imidazolium ionic liquid provided antibacterial activity to the experimental adhesive resin against biofilm formation of Streptococcus mutans.


Assuntos
Líquidos Iônicos , Pontos Quânticos , Antibacterianos , Cimentos Dentários , Óxidos , Tantálio
15.
Rev. cient. odontol ; 8(1): e010-e010, ene.-abr. 2020. tab.
Artigo em Espanhol | LILACS, LIPECS | ID: biblio-1095508

RESUMO

El presente trabajo busca realizar una revisión de la literatura para dar a conocer al personal ocupacionalmente expuesto a radiaciones ionizantes las ventajas y propiedades del concreto simple y la baritina para justificar su aplicación como materiales de blindaje en el diseño y construcción de muros en áreas donde se utilizan rayos X de uso odontológico, ya que estos, al no ser utilizados de manera segura, pueden tener efectos perjudiciales en la salud de las personas. En este trabajo también se describen las características generales de los rayos X que los hacen nocivos para la salud del personal ocupacionalmente expuesto, así como del público en general, por lo que surge en este punto el término de atenuación. Se encontró poca información sobre el tema, por lo que se desarrolló la relación existente entre ambos materiales y su importancia para dar información que pueda ser útil a todas las personas. Se concluyó que ambos materiales tienen la capacidad de bloquear y reducir la intensidad de la radiación, ya que el concreto actúa como un absorbente para reducir los efectos biológicos de la radiación y la baritina funciona como blindaje basado en el coeficiente de atenuación, por lo que ambos ofrecen una mayor resistencia y, al ser aplicados en conjunto, brindan una mayor protección para aquellas personas que puedan estar expuestas a rayos ionizantes. (AU)


The safety of the use of radiation in odontology must be guaranteed in order to avoid adverse effects to the health of dental staff and patients. The present study is a review of the literature on exposure to ionizing radiations and the advantages and properties which simple concrete and barite provide as shielding material in wall design and construction in areas of odontology in which X-rays are used. The general characteristics of X-rays which make them harmful to exposed workers and the general public are described. An attenuation coefficient is the fraction of an x-ray beam that is absorbed or scattered per unit thickness of the absorber. There is little information on this subject, however, it was found that both concrete and barite are able to block and reduce the intensity of radiation, with concrete acting as an absorbent to reduce the biological effects of radiation and barite acting as a shield. Based on the coefficient of attenuation these two materials provide greater resistance and their combined use allows greater protection against exposure to ionizing rays. (AU)


Assuntos
Humanos , Raios X , Cimentos Dentários , Materiais Dentários
16.
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
17.
J Appl Oral Sci ; 28: e20190499, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32348441

RESUMO

Enzymatic degradation of the hybrid layer can be accelerated by the activation of dentin metalloproteinases (MMP) during the bonding procedure. MMP inhibitors may be used to contain this process. Objective To evaluate the degree of conversion (DC%), dentin bond strength (µTBS) (immediate and after 1 year of storage in water), and nanoleakage of an experimental (EXP) and a commercial (SB) adhesive system, containing different concentrations of the MMP inhibitor GM1489: 0, 1 µM, 5 µM and 10 µM. Methodology DC% was evaluated by FT-IR spectroscopy. Dentin bond strength was evaluated by µTBS test. Half of beams were submitted to the µTBS test after 24 h and the other half, after storage for 1 year. From each tooth and storage time, 2 beams were reserved for nanoleakage testing. Data were analyzed using ANOVA and Tukey's test to compare means (α=0.05). Results All adhesive systems maintained the µTBS after 1 year of storage. Groups with higher concentrations of inhibitor (5 µM and 10 µM) showed higher µTBS values than groups without inhibitor or with 1 µM. The nanoleakage values of all groups showed no increase after 1 year of storage and values were similar for SB and EXP groups, in both storage periods. The inhibitor did not affect the DC% of the EXP groups, but the SB5 and SB10 groups showed higher DC% values than those of SB0 and SB1. Conclusions The incorporation of GM1489 in the adhesive systems had no detrimental effect on DC%. The concentrations of 5 µM GM1489 for SB and 5 µM or 10 µM for EXP provided higher µTBS than groups without GM1489, in the evaluation after 1 year of storage; whereas the concentration of inhibitor did not affect adhesive systems nanoleakage.


Assuntos
Cimentos Dentários/química , Dentina/química , Inibidores de Metaloproteinases de Matriz/química , Metacrilatos/química , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Análise de Variância , Colagem Dentária/métodos , Corrosão Dentária/métodos , Infiltração Dentária , Dentina/efeitos dos fármacos , Humanos , Teste de Materiais , Valores de Referência , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Estatísticas não Paramétricas , Propriedades de Superfície , Resistência à Tração , Fatores de Tempo
18.
J Adhes Dent ; 22(2): 139-147, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32322835

RESUMO

PURPOSE: To evaluate the degree of conversion (DC%), water sorption (Sp), solubility (Sl), dentin bond strength (µTBS) (immediate and after 12 months of storage), and the antibacterial effect of an experimental adhesive containing different concentrations (%) of proanthocyanidin (PA): 0, 1%, 2%, 4.5%, and 6% (PA0, PA1%, PA2%, PA4.5% and PA6%, respectively). MATERIALS AND METHODS: DC% was measured by FT-IR and the Sp and Sl were determined based on the ISO 4049 specification. For µTBS, resin composite buildups were constructed incrementally and specimens (n = 8) were sectioned to obtain sticks (1 mm2). The µTBS was evaluated after 24 h and 12 months of water storage at 37°C. The failure mode was analyzed. The antibacterial effects were evaluated by analyzing the bacterial growth (S. mutans) (n = 5) and antibiofilm activity (n = 5) of the adhesives by spectrophotometry. RESULTS: The incorporation of PA did not affect the Sp, Sl, or DC%. Immediate µTBS was similar for all groups. After 12 months, PA4.5% presented significantly higher µTBS than PA0, while the other groups did not differ from PA0 and PA4.5%. Groups PA0 and PA1% underwent significant reduction in µTBS. In the experimental groups PA2%, PA4.5% and PA6%, µTBS was maintained after storage. All groups showed antibacterial activity. CONCLUSION: Incorporation of 2%, 4.5%, and 6% PA maintained the dentin µTBS after 12-month storage, without affecting the Sp, Sl, or DC% of experimental adhesives. PA4.5% presented higher µTBS values than PA0 after 12 months. The adhesive presented antibacterial effect irrespective of PA concentration.


Assuntos
Colagem Dentária , Proantocianidinas , Antibacterianos , Cimentos Dentários , Adesivos Dentinários , Teste de Materiais , Metacrilatos , Cimentos de Resina , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Oral Health Prev Dent ; 18(2): 145-152, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32238986

RESUMO

PURPOSE: To evaluate the microtensile bond strength of dentine/self-adhesive resin cement interface after several treatments on a dentine surface. MATERIALS AND METHODS: Twenty-eight human molars were selected and divided into four groups: no treatment (control (C)); 2% chlorhexidine digluconate (CHX); 25% polyacrylic acid (PA); and 23 ppm dispersive solution of silver nanoparticle (SN). Prepolymerised TPH resin composite (Dentsply) blocks were luted on the dentine surface using RelyX U200 self-adhesive resin cement (3M ESPE). Microtensile bond strength was measured (MPa) in a universal testing machine 24 h and 6 months after the bonding process. The fractured specimens were examined in an optical microscope and classified according to the fracture pattern. A representative sample of each group was observed by scanning electronic microscope. Data were submitted to analysis of variance (ANOVA) and Tukey's test to compare the mean among the groups (p <0.05). RESULTS: The highest microtensile bond strength values after 24 h were found for the PA group (13.34 ± 6.36 MPa), with no statistically significant difference for the C group (9.76 ± 3.11 Mpa). After 6 months, the highest microtensile bond strength values were found for the C group (9.09 ± 3.27 Mpa), with statistically significant difference only for the CHX group (2.94 ± 1.66 MPa). There was statistically significant difference only for the PA group when comparing the periods studied. Regardless of the surface treatment applied, there were more adhesive failures in both periods of time. CONCLUSION: Dentinal pretreatment with PA, as well as use of SN before the bonding procedure of self-adhesive resin cement to dentine, may be alternative bonding protocols.


Assuntos
Colagem Dentária , Nanopartículas Metálicas , Resinas Compostas , Cimentos Dentários , Análise do Estresse Dentário , Dentina , Adesivos Dentinários , Humanos , Teste de Materiais , Cimentos de Resina , Prata , Propriedades de Superfície , Resistência à Tração
20.
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
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