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1.
Materials (Basel) ; 16(6)2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36984260

RESUMO

The aim of this study is to evaluate the biomechanical behavior of the porcelain laminate veneer restorations (PLV) of the maxillary central incisor luted with two types of resin cements having different incisal preparations: butt joint and palatal chamfer. Biomechanical analyses were performed using the micro-CT-based finite element models, and von Mises stress and strain values of the PLV, resin cement, adhesive layer, and tooth structure were computed. The PLV with butt joint preparation showed larger stress values than those of restored with palatal chamfer preparation, regardless of the elasticity of the cement and loading conditions. An increase in the elasticity modulus of the resin cement induced slightly larger stresses on the adhesive layer, tooth tissues, and restorative materials. Overall, this study demonstrates the role of the preparation design and luting materials on the mechanical behavior of the PLV restorations and discusses the potential failure mechanisms of the PLV restorations under different loading mechanisms.

2.
Am J Dent ; 35(6): 308-314, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36508186

RESUMO

PURPOSE: To evaluate the fracture resistance of endodontically treated premolars restored with CAD-CAM onlay restorations. METHODS: 60 extracted mandibular first premolars were selected and at first divided into three groups regarding treatment options: MOD onlay with buccal cusp coverage, MOD onlay with buccal cusp coverage + endodontic treatment, MOD onlay with buccal cusp coverage + endodontic treatment + fiber post. Then, all groups were divided into subgroups (n=10) according to the restorative material used: IPS e.max CAD and Lava Ultimate. Each group was submitted to 5,000 thermal cycles, embedded in acrylic resin and secured in a universal testing machine respectively. A compressive load was applied until fracture, at a crosshead speed of 0.5 mm/minute. Statistical significance among each group was analyzed using one-way ANOVA and Bonferroni tests. RESULTS: Statistically, endodontically treated IPS e.max onlays had numerically the lowest average fracture resistance [753.1 (± 224.9) N/mm² ] among all treatment options. IPS e.max onlays treated with fiber posts had significantly higher resistance than that of endodontically treated IPS e.max CAD group (P= 0.013). Endodontically treated teeth restored with Lava Ultimate onlays [1,381.0 (± 471.7) N/mm²] showed significantly higher averages of fracture resistance than IPS e.max CAD onlays. CLINICAL SIGNIFICANCE: CAD-CAM composite (resin nanoceramic) onlays resist greater forces compared to ceramic restorations. Fiber posts could improve the fracture resistance of endodontically treated mandibular premolars following the ceramic CAD-CAM onlays.


Assuntos
Fraturas dos Dentes , Dente não Vital , Humanos , Porcelana Dentária , Análise do Estresse Dentário , Restaurações Intracoronárias , Dente não Vital/tratamento farmacológico , Resinas Compostas , Desenho Assistido por Computador
3.
Microsc Res Tech ; 85(2): 499-509, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34528737

RESUMO

The purpose was to investigate the surface characteristics of various resin-based materials by immersing in probiotic beverages. A total of 420 disc-shaped samples (5 mm × 2 mm) were prepared from resin-based composites. Samples were divided into four groups and immersed for 10 min/day for 1 month in either a probiotic sachet, kefir, kombucha, or artificial saliva (control). Surface roughness was measured at baseline and 1 month. One sample of each of the tested materials was examined under nanoindentation to evaluate the reduced elasticity modulus and nanohardness scores. Scanning electron microscopy (SEM) was used to compare surface differences. Data were analyzed statistically using one-way ANOVA test and the significance was set at p < .05. The lowest roughness scores were observed in Z250, Estelite Bulk Fill, and HRi ENA in most of the test groups. Among conventional composites, Z250 group had the highest nanohardness and elasticity modulus scores. Among bulk-fill composites, Estelite Bulk Fill Flow had the lowest surface roughness after immersion in probiotic beverages and the highest nanohardness values. Reveal HD, as a bulk-fill group showed higher surface roughness and considerably lower nanohardness and elasticity modulus scores. Maximum height levels of samples were recorded. SEM images revealed voids and microcracks on the surfaces of test materials. Dentists may prefer Z250 as microhybrid and Estelite Bulk Fill Flow as bulk-fill composites for the restorations of patients who consume gut-friendly drinks regularly. When there are various types of materials, nanoindentation is a useful method for evaluating surface alterations and sensible comparisons.


Assuntos
Resinas Compostas , Probióticos , Bebidas , Materiais Dentários , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Prebióticos , Propriedades de Superfície
4.
Med Biol Eng Comput ; 59(4): 813-824, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33728596

RESUMO

The purpose of this study was to determine the effects of prosthetic materials and crown/implant (C/I) ratio on short implants with a marginal bone resorption. Three-dimensional finite element analysis was used to simulate stress distribution under static loading in non-resorption and resorption scenarios (3-mm vertical bone loss) in implants restored with single crowns and C/I ratios of 1:1, 1.5:1, and 2:1 were evaluated. Different crown materials were used: porcelain-fused to metal, porcelain-fused to zirconia, monolithic zirconia, and zirconia-based crown veneered with indirect composite resin. The C/I ratio, the peri-implant bone resorption, and the loading conditions were the key factors affecting the generated stress in short implants. In non-resorption models, von Mises stress ranged between 50 and 105 MPa whereas in resorption models, the values ranged from 168 to 322 MPa, both increasing with the higher C/I ratio under oblique forces. Under axial loading, the C/I ratio did not influence the stress values as the presence of resorption was the only parameter increasing, 57 MPa for the non-resorption models and 101 MPa for the resorption models, respectively. Preference of a prosthetic material was ineffective on the distribution of stress in the bone and implant structure under static loading in any models. The peri-implant bone resorption and a higher C/I ratio in short implants increase the stress values under both axial and oblique forces, whereas the crown material does not influence stress distribution in the surrounding bone and implant structure.


Assuntos
Reabsorção Óssea , Implantes Dentários , Resinas Compostas , Coroas , Análise do Estresse Dentário , Análise de Elementos Finitos , Humanos , Estresse Mecânico
5.
Eur Oral Res ; 54(1): 1-8, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32518904

RESUMO

PURPOSE: The aim of this study was to evaluate the effect of a surface sealant on the surface roughness of different composites and compare their microhardness values. MATERIALS AND METHODS: Sixty disc-shaped specimens were prepared and assigned to 6 groups (n =10). Groups were prepared as follows; Group 1 (Herculite XRV Ultra), Group 2 (Beautifil Bulk Restorative) and Group 3 (Filtek Bulk Fill Posterior Restorative). Groups 4, 5, and 6 were prepared by applying a surface sealant (BisCover LV) on the specimens in groups 1, 2 and 3. Surface hardness of the discs in group 1, 2, and 3 and surface roughness of the discs in all groups were measured using the Vickers hardness test and a profilometer, respectively. One-way ANOVA was used to test for differences among the groups. RESULTS: No significant differences were observed in the microhardness and roughness between the experimental and control groups for each restorative materials. Group 3 showed the highest surface hardness and group 4 showed the lowest surface roughness values. CONCLUSION: Using the BisCover LV resin after the polishing step has no significant effect on the surface roughness. The highest hardness values were obtained for the Filtek Bulk Fill Posterior Restorative after the polishing step. The smoothest surfaces were obtained for all experimental groups using the BisCover LV resin after the polishing step, Herculite XRV Ultra showed lower average roughness values than the other materials.

6.
Radiology ; 297(1): E232-E235, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32384020
7.
Braz. dent. sci ; 22(2): 234-242, 2019. tab, ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-996919

RESUMO

Objective: The objective of this study was to evaluate the compressive strength, flexural strength and flexural modulus of high-viscosity, low-viscosity bulk-fill, and conventional nanohybrid resin composite materials alone and when covered with nano-hybrid resin composite at different incremental thicknesses on the bulk-fill composites. Material and Methods: Specimens (N=60) were fabricated from the following materials or their combinations (n=10 per group): a) conventional nano-hybrid composite Z550 (FK), b) high-viscosity bulk-fill composite (Tetric N Ceram-TBF), c) low-viscosity bulk-fill composite SDR (SDR), d) Sonicfill (SF), e) SDR (2 mm)+FK (2 mm), f) SDR (4 mm)+FK (4 mm). After 24 h water storage, compressive strength was measured in a universal testing machine (1 mm/min). Additional specimens (N=40) (25x2x2 mm3) were made from FK, TBF, SDR and SF in order to determine the flexural strength and the flexural modulus, (n=10) and subjected to three-point bending test (0.5 mm/min). Data were analyzed using one-way ANOVA and Tamhane's T2 post-hoc tests (p p<0.05). Results: The mean compressive strength (MPa) of the nano-hybrid composite (FK) was significantly higher (223.8±41.3) than those of the other groups (123±27 - 170±24) (p <0.001). SDR (4 mm)+FK (2 mm) showed significantly higher compressive strength than when covered with 4 mm (143±30) or when used alone (146±11) (p <0.05). The mean flexural strength (159±31) and the flexural modulus of FK (34±7) was significantly higher than that of the high- or low-viscosity bulk-fill composites (p<0.001). The mean flexural strength of SF (132±20) was significantly higher compared to TBF (95±25) (p <0.05). Conclusion: Bulk-fill resin composites demonstrated poorer mechanical properties compared to nano-hybrid composite but similar to that of SF. Increasing the thickness of low-viscosity bulk-fill composite (SDR) from 2 to 4 mm underneath the nano-hybrid composite (FK) can improve the mechanical properties of the bulk-fill composites.(AU)


Objetivo: O objetivo deste estudo foi avaliar a resistência à compressão, resistência à flexão e módulo de flexão de materiais compósitos de alta viscosidade, baixa viscosidade e compósitos nanohíbridos convencionais e quando cobertos com resina composta nano-híbrida em diferentes espessuras incrementais sobre os compósitos de resina tipo bulkfilll. Material e Métodos: Os espécimes (N = 60) foram fabricados a partir dos seguintes materiais ou suas combinações (n = 10 por grupo): a) compósito nano-híbrido convencional Z550 (FK), b) compósito de bulk-fill de alta viscosidade (Tetric N CeramTBF), c) compósito SDR (SDR) de bulk-fill de baixa viscosidade, d) Sonicfill (SF), e) SDR (2 mm) + FK (2 mm), f) SDR (4 mm) + FK (4 mm). Após 24 h de armazenamento em água, a resistência à compressão foi medida em uma máquina universal de ensaios (1 mm / min). Espécimes adicionais (N = 40) (25x2x2 mm3) foram confeccionados com FK, TBF, SDR e SF para determinação da resistência à flexão e do módulo de flexão, (n = 10) e submetidos ao teste de flexão de três pontos (0,5 mm / min). Os dados foram analisados utilizando one-way ANOVA e testes post-hoc T2 de Tamhane (p <0,05). Resultados: A resistência média à compressão (MPa) do compósito nano-híbrido (FK) foi significativamente maior (223,8 ± 41,3) que os demais grupos (123 ± 27 - 170 ± 24) (p <0,001). SDR (4 mm) + FK (2 mm) apresentou resistência à compressão significativamente maior do que quando coberta com 4 mm (143 ± 30) ou quando usada sozinha (146 ± 11) (p <0,05). A resistência à flexão média (159 ± 31) e o módulo de flexão de FK (34 ± 7) foram significativamente maiores do que os compósitos do tipo bulk-fill de alta ou baixa viscosidade (p <0,001). A resistência à flexão média do FS (132 ± 20) foi significativamente maior em comparação ao TBF (95 ± 25) (p <0,05). Conclusão: Os compósitos de resina do tipo bulk-fill demonstraram propriedades mecânicas mais insatisfatórias em comparação com o compósito nano-híbrido, mas semelhantes aos do SF. O aumento da espessura do composto de bulkfilll de baixa viscosidade (SDR) de 2 a 4 mm sob o compósito nano-híbrido (FK) pode melhorar as propriedades mecânicas dos compósitos de bulk-fill.(AU)


Assuntos
Resistência à Tração , Força de Mordida , Resinas Compostas
8.
J Mech Behav Biomed Mater ; 75: 302-313, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28768230

RESUMO

Main objective of this study is to investigate the thermal behavior of ceramic laminate veneer restorations of the maxillary central incisor with different incisal preparations such as butt joint and palatinal chamfer using finite element method. In addition, it is also aimed to understand the effect of different thermal loads which simulates hot and cold liquid imbibing in the mouth. Three-dimensional solid models of the sound tooth and prepared veneer restorations were obtained using micro-computed tomography images. Each ceramic veneer restoration was made up of ceramic, luting resin cement and adhesive layer which were generated based on the scanned images using computer-aided design software. Our solid model also included the remaining dental tissues such as periodontal ligament and surrounding cortical and spongy bones. Time-dependent linear thermal analyses were carried out to compare temperature changes and stress distributions of the sound and restored tooth models. The liquid is firstly in contact with the crown area where the maximum stresses were obtained. For the restorations, stresses on palatinal surfaces were found larger than buccal surfaces. Through interior tissues, the effect of thermal load diminished and smaller stress distributions were obtained near pulp and root-dentin regions. We found that the palatinal chamfer restoration presents comparatively larger stresses than the butt joint preparation. In addition, cold thermal loading showed larger temperature changes and stress distributions than those of hot thermal loading independent from the restoration technique.


Assuntos
Cerâmica , Análise do Estresse Dentário , Facetas Dentárias , Microtomografia por Raio-X , Resinas Compostas , Porcelana Dentária , Análise de Elementos Finitos , Incisivo , Estresse Mecânico
9.
J Adhes Dent ; 17(6): 499-504, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26734673

RESUMO

PURPOSE: To evaluate the effects of different antioxidant treatments on the microtensile bond strength of an adhesive system to sodium hypochlorite (NaOCl)-treated dentin. MATERIALS AND METHODS: Thirty extracted third molars were sectioned 3 mm below the occlusal surface and divided into six groups according to the antioxidant treatment received: control group: distilled water; NaOCl group: 5.25% NaOCl and distilled water; proanthocyanidin (PA) group: 5.25% NaOCl, 5% PA and distilled water; 1-week storage group: 5.25% NaOCl and storage for 1 week in distilled water; Accel group: 5.25% NaOCl, Accel, and distilled water; noni group: 5.25% NaOCl, noni fruit juice, and distilled water. NaOCl, PA, Accel, noni, and distilled water were administered for 30 s, 10 min, 30 s, 10 min, and 30 s, respectively. A self-etching adhesive system (Single Bond Universal Adhesive) was applied to each specimen and a resin composite (Filtek Z550) was built up to a height of 5 mm on the dentin surface. Each specimen was serially sectioned to obtain sticks with a cross-sectional area of 1 mm2, and their microtensile bond strength was determined. Statistical differences between groups were analyzed using one-way ANOVA and Tamhane's T2 test. RESULTS: Microtensile bond strength in the NaOCl group was significantly lower than in all other groups. However, there were no significant differences in the bond strength between the groups treated with different antioxidants. CONCLUSIONS: NaOCl significantly reduced the microtensile bond strength of the adhesive system. The application of PA, Accel, and noni fruit juice to NaOCl-treated dentin significantly improved the microtensile bond strength.


Assuntos
Antioxidantes/química , Colagem Dentária , Adesivos Dentinários/química , Dentina/ultraestrutura , Irrigantes do Canal Radicular/química , Hipoclorito de Sódio/química , Bis-Fenol A-Glicidil Metacrilato/química , Resinas Compostas/química , Dentina/efeitos dos fármacos , Sucos de Frutas e Vegetais , Humanos , Teste de Materiais , Morinda , Proantocianidinas/química , Irrigantes do Canal Radicular/farmacologia , Hipoclorito de Sódio/farmacologia , Estresse Mecânico , Resistência à Tração , Fatores de Tempo , Tolueno/análogos & derivados , Tolueno/química , Água/química
10.
J Adv Prosthodont ; 6(6): 434-43, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25551002

RESUMO

PURPOSE: The purpose of this study was to evaluate and compare the effects of different surface pretreatment techniques on the surface roughness and shear bond strength of a new self-adhering flowable composite resin for use with lithium disilicate-reinforced CAD/CAM ceramic material. MATERIALS AND METHODS: A total of one hundred thirty lithium disilicate CAD/CAM ceramic plates with dimensions of 6 mm × 4 mm and 3 mm thick were prepared. Specimens were then assigned into five groups (n=26) as follows: untreated control, coating with 30 µm silica oxide particles (Cojet™ Sand), 9.6% hydrofluoric acid etching, Er:YAG laser irradiation, and grinding with a high-speed fine diamond bur. A self-adhering flowable composite resin (Vertise Flow) was applied onto the pre-treated ceramic plates using the Ultradent shear bond Teflon mold system. Surface roughness was measured by atomic force microscopy. Shear bond strength test were performed using a universal testing machine at a crosshead speed of 1 mm/min. Surface roughness data were analyzed by one-way ANOVA and the Tukey HSD tests. Shear bond strength test values were analyzed by Kruskal-Wallis and Mann-Whitney U tests at α=.05. RESULTS: Hydrofluoric acid etching and grinding with high-speed fine diamond bur produced significantly higher surface roughness than the other pretreatment groups (P<.05). Hydrofluoric acid etching and silica coating yielded the highest shear bond strength values (P<.001). CONCLUSION: Self-adhering flowable composite resin used as repair composite resin exhibited very low bond strength irrespective of the surface pretreatments used.

11.
J Adhes Dent ; 16(1): 7-14, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24027770

RESUMO

PURPOSE: This study compared the microtensile bond strengths (µTBS) of two different self-etching (SE) and etchand- rinse (ER) adhesive systems to enamel affected by hypoplastic amelogenesis imperfecta (HPAI) and analyzed the enamel etching patterns created by the two adhesive systems using scanning electron microscopy (SEM). MATERIALS AND METHODS: Sixteen extracted HPAI-affected molars were used for the bond strength tests and 2 molars were examined under SEM for etching patterns. The control groups consisted of 12 healthy third molars for µTBS tests and two molars for SEM. Mesial and distal surfaces of the teeth were slightly ground flat. The adhesive systems and composite resin were applied to the flat enamel surfaces according to the manufacturers' instructions. The tooth slabs containing composite resin material on their mesial and distal surfaces were cut in the mesio-distal direction with a slow-speed diamond saw. The slabs were cut again to obtain square, 1-mm-thick sticks. Finally, each stick was divided into halves and placed in the µTBS tester. Bond strength tests were performed at a speed of 0.5 mm/min. Data were analyzed with two-way ANOVA and Tukey's tests. RESULTS: There was no significant difference between the bond strength values of ER and SE adhesives (p > 0.05). However, significant differences were found between HPAI and control groups (p < 0.05). HPAI-affected enamel surfaces exhibited mild intra- and inter-prismatic enamel etching patterns after orthophosphoric acid application, while conditioning of HPAI-affected enamel with SE primer created a slightly rough and grooved surface. CONCLUSION: SE and ER adhesive systems provide similar bond strengths to HPAI-affected enamel surfaces.


Assuntos
Amelogênese Imperfeita/patologia , Colagem Dentária , Cimentos Dentários/química , Esmalte Dentário/ultraestrutura , Condicionamento Ácido do Dente/métodos , Resinas Compostas/química , Análise do Estresse Dentário/instrumentação , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Ácidos Fosfóricos/química , Cimentos de Resina/química , Estresse Mecânico , Resistência à Tração
12.
J Appl Oral Sci ; 21(2): 124-31, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23739850

RESUMO

OBJECTIVES: This study evaluated the effect of sports and energy drinks on the surface hardness of different composite resin restorative materials over a 1-month period. MATERIAL AND METHODS: A total of 168 specimens: Compoglass F, Filtek Z250, Filtek Supreme, and Premise were prepared using a customized cylindrical metal mould and they were divided into six groups (N=42; n=7 per group). For the control groups, the specimens were stored in distilled water for 24 hours at 37°C and the water was renewed daily. For the experimental groups, the specimens were immersed in 5 mL of one of the following test solutions: Powerade, Gatorade, X-IR, Burn, and Red Bull, for two minutes daily for up to a 1-month test period and all the solutions were refreshed daily. Surface hardness was measured using a Vickers hardness measuring instrument at baseline, after 1-week and 1-month. Data were statistically analyzed using Multivariate repeated measure ANOVA and Bonferroni's multiple comparison tests (α=0.05). RESULTS: Multivariate repeated measures ANOVA revealed that there were statistically significant differences in the hardness of the restorative materials in different immersion times (p<0.001) in different solutions (p<0.001). The effect of different solutions on the surface hardness values of the restorative materials was tested using Bonferroni's multiple comparison tests, and it was observed that specimens stored in distilled water demonstrated statistically significant lower mean surface hardness reductions when compared to the specimens immersed in sports and energy drinks after a 1-month evaluation period (p<0.001). The compomer was the most affected by an acidic environment, whereas the composite resin materials were the least affected materials. CONCLUSIONS: The effect of sports and energy drinks on the surface hardness of a restorative material depends on the duration of exposure time, and the composition of the material.


Assuntos
Resinas Compostas/química , Bebidas Energéticas , Análise de Variância , Cimentos de Ionômeros de Vidro/química , Testes de Dureza , Humanos , Teste de Materiais , Propriedades de Superfície/efeitos dos fármacos , Fatores de Tempo , Água/química
13.
J. appl. oral sci ; 21(2): 124-131, Mar-Apr/2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-674354

RESUMO

Objectives: This study evaluated the effect of sports and energy drinks on the surface hardness of different composite resin restorative materials over a 1-month period. Material and Methods: A total of 168 specimens: Compoglass F, Filtek Z250, Filtek Supreme, and Premise were prepared using a customized cylindrical metal mould and they were divided into six groups (N=42; n=7 per group). For the control groups, the specimens were stored in distilled water for 24 hours at 37°C and the water was renewed daily. For the experimental groups, the specimens were immersed in 5 mL of one of the following test solutions: Powerade, Gatorade, X-IR, Burn, and Red Bull, for two minutes daily for up to a 1-month test period and all the solutions were refreshed daily. Surface hardness was measured using a Vickers hardness measuring instrument at baseline, after 1-week and 1-month. Data were statistically analyzed using Multivariate repeated measure ANOVA and Bonferroni's multiple comparison tests (α=0.05). Results: Multivariate repeated measures ANOVA revealed that there were statistically significant differences in the hardness of the restorative materials in different immersion times (p<0.001) in different solutions (p<0.001). The effect of different solutions on the surface hardness values of the restorative materials was tested using Bonferroni's multiple comparison tests, and it was observed that specimens stored in distilled water demonstrated statistically significant lower mean surface hardness reductions when compared to the specimens immersed in sports and energy drinks after a 1-month evaluation period (p<0.001). The compomer was the most affected by an acidic environment, whereas the composite resin materials were the least affected materials. Conclusions: The effect of sports and energy drinks on the surface hardness of a restorative material depends on the duration of exposure time, and the composition of the material.


Assuntos
Humanos , Resinas Compostas/química , Bebidas Energéticas , Análise de Variância , Cimentos de Ionômeros de Vidro/química , Testes de Dureza , Teste de Materiais , Propriedades de Superfície/efeitos dos fármacos , Fatores de Tempo , Água/química
14.
Dent Mater J ; 31(5): 729-36, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23037834

RESUMO

The purpose of this study was to evaluate the effect of sports and energy drinks on the surface hardness of different restorative materials over a 6-month period. Forty-two disk-shaped specimens were prepared for each of the four restorative materials tested: Compoglass F, Filtek Z250, Filtek Supreme, and Premise. Specimens were immersed for 2 min daily, up to 6 months, in six storage solutions (n=7 per material for each solution): distilled water, Powerade, Gatorade, X-IR, Burn, and Red Bull. Surface hardness was measured at baseline, after 1 week, 1 month, and 6 months. Data were analyzed statistically using repeated measures ANOVA followed by the Bonferroni test for multiple comparisons (α=0.05). Surface hardness of the restorative materials was significantly affected by both immersion solution and immersion period (p<0.001). All tested solutions induced significant reduction in surface hardness of the restorative materials over a 6-month immersion period.


Assuntos
Bebidas , Resinas Compostas/química , Materiais Dentários/química , Restauração Dentária Permanente , Bebidas Energéticas , Bebidas Gaseificadas , Cimentos de Ionômeros de Vidro/química , Dureza , Humanos , Concentração de Íons de Hidrogênio , Imersão , Soluções Isotônicas/química , Cura Luminosa de Adesivos Dentários , Teste de Materiais , Nanocompostos/química , Polimerização , Propriedades de Superfície , Fatores de Tempo , Água/química
15.
J Dent ; 40 Suppl 2: e55-63, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22713737

RESUMO

OBJECTIVES: This study assessed the effects of three sports drinks on the color stability of two nanofilled and two microhybrid composite materials after 1-month and 6-month periods. MATERIALS AND METHODS: Twenty-eight disc-shaped specimens (diameter: 10mm and thickness: 2mm) each were made from four resin composites (Clearfil Majesty Posterior, Filtek Supreme, Clearfil APX, and Filtek Z250). All the specimens were stored in distilled water for 24h at 37°C. Then, the baseline color values (L*a*b*) of each specimen were measured using a spectrophotometer according to the CIEL*a*b* color scale. Seven randomly selected specimens from each composite material were then immersed in one of the three sports drinks (Powerade, Red Bull, and Burn) or distilled water (control) for 1 and 6 months. After each immersion, the color values of each specimen were remeasured, and the color change value (ΔE) was calculated. The data were evaluated using the Kruskal-Wallis and Mann-Whitney U-tests. RESULTS: The tested resin composites showed color changes over the 6-month evaluation periods. At 1 month, highest level of color changes was observed in the Clearfil APX specimens immersed in Burn (p<0.01). Clearfil Majesty Posterior showed less discoloration in all the composite materials tested after 6 months (p<0.001). Independent of the composite materials tested, Burn resulted in the highest level of discoloration after both immersion periods (p<0.01). CONCLUSION: All the test solutions used in the present study caused greater discoloration than the clinically acceptable level of threshold (ΔE<3.3) over the 6-month evaluation period except for Clearfil Majesty Posterior immersed in distilled water (2.91±0.28). The effect of each solution on the color stability of the composite materials depended on the type of solution, exposure time, and composition of the composite material. CLINICAL SIGNIFICANCE: The effect of a solution on color stability of composite materials depends on the type of solution, exposure time, and composition of the material. In clinical practice, patients should be aware of the staining effects and erosive potential of sports drinks if consumed a longer period of time.


Assuntos
Bebidas , Resinas Compostas/química , Materiais Dentários/química , Bebidas Energéticas , Nanocompostos/química , Algoritmos , Compostos de Bário/química , Cerâmica/química , Cor , Humanos , Imersão , Teste de Materiais , Metacrilatos/química , Dióxido de Silício/química , Espectrofotometria , Propriedades de Superfície , Temperatura , Fatores de Tempo , Zircônio/química
16.
Agri ; 20(4): 17-22, 2008 Oct.
Artigo em Turco | MEDLINE | ID: mdl-19117152

RESUMO

Postoperative pain is an important parameter in discharge and rehabilitation in daycase arthroscopic knee surgery. This study compared the efficacy of intraarticular application of lornoxicam, bupivacaine and placebo on postoperative pain after arthroscopic knee surgery. With the approval of the local ethics committee and informed consent of the patients, 90 patients (ASA score I-II), aged between 18-65 years undergoing arthroscopic meniscectomy were included in this randomized, blinded, prospective study and were divided into three groups (30 patients each): 8 mg lornoxicam was applied to Group L (GL), 50 mg bupivacaine to Group B (GB) and normal saline to Group S (GS) in 20 mL volume intraarticularly. Postoperative analgesia was maintained by intravenous tramadol-HCl 50 mg/h at the first 4 h and then paracetamol 500 mg plus codeine 7.5 mg preparation as needed. The numeric rating scale (NRS) values were evaluated at rest and at active-passive motion at 4, 12, 24 and 48 h, total analgesic consumption were recorded. There were statistically significant differences between GS and GL and GS and GB in term of tramadol consumption (p < 0.05 and p < 0.05). The analgesiconsumption of GL patients at the end of 48 h were lower than GB and GS (p < 0.001 and p < 0.05). The NRS values of GL were always lower than the other groups with statistical significance at certain times. We concluded that intraarticular lornoxicam provided better pain control than bupivacaine and saline in arthroscopic knee surgery.


Assuntos
Anestésicos Locais/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Bupivacaína/uso terapêutico , Dor Pós-Operatória/prevenção & controle , Piroxicam/análogos & derivados , Adolescente , Adulto , Idoso , Artroscopia , Feminino , Humanos , Injeções Intra-Articulares , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Piroxicam/uso terapêutico , Estudos Prospectivos , Amplitude de Movimento Articular , Cloreto de Sódio , Resultado do Tratamento , Adulto Jovem
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