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1.
Odovtos (En linea) ; 25(1)abr. 2023.
Artigo em Inglês | LILACS, SaludCR | ID: biblio-1422190

RESUMO

Dental fluorosis can cause changes in the enamel surface, conditioning its functionality and esthetics. The application of dental adhesives is a treatment option; however, their use on fluorotic teeth can result in limitations. The aim of this study was to compare the shear bond strength of two different adhesives, one with 10-MDP and one without 10-MDP, in different degrees of dental fluorosis.This is an in vitro study on dental enamel samples, a total of 180 samples with the inclusion criteria were treated, randomly divided into two groups of 90, according to the type of dental adhesive, where each group was again divided into three groups of 30 samples, representing different degrees of dental fluorosis according to the Thylstrup-Fejerskov index (Group I: TF1 and TF2; Group II: TF3; Group III: TF4). Normality tests, two-factor ANOVA, and post-hoc tests were used to determine differences between the groups, with a significance level of 95%. As results, a statistically significant difference was shown between the use of dental adhesive with 10-MDP and the three groups of dental fluorosis (p=0.011), in addition, a Tukey post-hoc test on the groups treated with 10-MDP adhesive revealed a statistically significant difference between group I versus group II, and group I versus group III, (p=<0.05). It is concluded that the use of adhesive systems with 10-MDP presents a better shear bond strength on enamel with dental fluorosis grades I and II in the Thylstrup-Fejerskov index.


La fluorosis dental puede ocasionar cambios en la superficie del esmalte, condicionando su funcionalidad y estética, la aplicación de adhesivos dentales es una opción de tratamiento, sin embargo, su uso en dientes fluoroticos puede resultar en limitaciones. El objetivo de este estudio consistió en comparar la fuerza de adhesión a la cizalladura de dos diferentes adhesivos, uno con 10-MDP y otro sin 10-MDP, en diferentes grados de fluorosis dental. Se trata de un estudio in vitro en muestras de esmalte dental, un total de 180 muestras con los criterios de inclusión fueron tratadas, aleatoriamente divididas en dos grupos de 90, de acuerdo al tipo de adhesivo dental, donde cada grupo fue dividido nuevamente en tres grupos de 30 muestras, representando diferentes grados de fluorosis dental según el índice de Thylstrup- Fejerskov (Grupo I: TF1 y TF2; Grupo II: TF3; Grupo III: TF4). Para determinar diferencias entre los grupos se utilizaron pruebas de normalidad, ANOVA de dos factores, y pruebas post-hoc, con un nivel de significancia de 95%. Como resultados, se mostró una diferencia estadísticamente significativa entre el uso de adhesivo dental con 10- MDP y los tres grupos de fluorosis dental (p=0.011), además, una prueba post hoc de Tukey sobre los grupos tratados con adhesivo 10-MDP revelaron una diferencia estadísticamente significativa entre el grupo I frente al grupo II, y el grupo I frente al grupo III, (p=<0.05) Se concluye que el uso de sistemas adhesivos con 10-MDP presentan una mejor resistencia de adhesión al cizallamiento en esmalte con grados de fluorosis dental I y II en el índice de Thylstrup-Fejerskov


Assuntos
Adesivos Dentinários/uso terapêutico , Fluorose Dentária/diagnóstico , Cimentos de Resina
2.
Braz. dent. sci ; 26(4): 1-10, 2023. ilus, tab
Artigo em Inglês | LILACS, BBO | ID: biblio-1523773

RESUMO

Objective: The aim of the study was to evaluate the short and long-term effects of different surface treatments on the bond strengths of zirconia. Material and Methods: 225 blocks of sintered zirconia samples (4 x 4 x 3 mm) were divided into five groups and subjected to different surface treatments: control group (without surface treatment), alumina group (sandblasting [25-µm-aluminum-oxide]), alumina+Ambar Universal-APS (AU) group, CoJet group (silica-coated [30-µm silica-modified aluminum particles]), and CoJet+AU group. Subsequently, zirconia samples were cemented against resin samples (total dimensions: 8x8x6mm) and assigned to three storage conditions: dry, humid (artificial saliva at 37°C for 30-days) or thermocycling [100.000-cycles] (n=15 per group). The microtensile bond strength (µTBS) was determined using a universal testing machine. The failure modes were observed and analyzed using a stereomicroscope. Normality tests, descriptive statistics, and two-way ANOVA, followed by post-hoc comparisons, were performed to evaluate the effect of surface treatments and storage conditions on µTBS (α=0.05). Results: µTBS was influenced by surface treatment in the short and long-term (P<0.0001). The highest values were found in CoJet+AU in dry (33.51 ±2.48 MPa), humid (32.87 ±2.68 MPa) and thermocycling (21.37 ±1.68 MPa) storage conditions compared with others. Interestingly, no significant differences in µTBS were found among alum +AU and CoJet alone under any of the three storage conditions. Adhesive failure increased in all groups after thermocycling, but CoJet+AU had the lowest values of adhesive failure compared with others. Conclusion: The combination of CoJet and Ambar universal as a surface treatment for zirconia specimens provides significantly higher short and long-term bond strengths of adhesive cementation (AU)


Objetivo: O objetivo do estudo foi avaliar os efeitos de curto e longo prazo de diferentes tratamentos de superfície na resistência de adesão da zircônia. Material e Métodos: 225 blocos de amostras de zircônia sinterizada (4 x 4 x 3 mm) foram divididos em cinco grupos e submetidos a diferentes tratamentos de superfície: grupo controle (sem tratamento de superfície), grupo de alumina (jateamento de 25 µm de óxido de alumínio), grupo alumina+Ambar Universal-APS (AU), grupo CoJet (partículas de alumínio modificadas por sílica de 30 µm), e grupo CoJet+AU. Posteriormente, as amostras de zircônia foram cimentadas em amostras de resina (dimensões totais: 8x8x6mm) e designadas para três condições de armazenamento: seco, úmido (saliva artificial a 37°C por 30 dias) ou ciclagem térmica (100.000 ciclos) (n=15 por grupo). A resistência de adesão de microtensão (µTBS) foi determinada usando uma máquina de teste universal. Os modos de falha foram observados e analisados usando um estereomicroscópio. Testes de normalidade, estatísticas descritivas e ANOVA de duas vias, seguidas de comparações pos-hoc, foram realizados para avaliar o efeito dos tratamentos de superfície e das condições de armazenamento na µTBS (α=0.05). Resultados: A µTBS foi influenciada pelo tratamento de superfície a curto e longo prazo (P<0.0001). Os valores mais altos foram encontrados em CoJet+AU nas condições de armazenamento a seco (33.51 ±2.48 MPa), úmido (32.87 ±2.68 MPa) e ciclagem térmica (21.37 ±1.68 MPa) em comparação com os outros. Curiosamente, não foram encontradas diferenças significativas na µTBS entre alum +AU e CoJet sozinho em nenhuma das três condições de armazenamento. A falha adesiva aumentou em todos os grupos após a ciclagem térmica, mas CoJet+AU teve os valores mais baixos de falha adesiva em comparação com os outros. Conclusão: A combinação de CoJet e Ambar Universal como tratamento de superfície para espécimes de zircônia proporciona resistências de adesão significativamente mais altas a curto e longo prazo para cimentação adesiva. (AU)


Assuntos
Cimentos Dentários
3.
Braz. dent. sci ; 25(1): 1-9, 2022. tab, ilus
Artigo em Inglês | LILACS, BBO | ID: biblio-1361885

RESUMO

Objetivo: O objetivo foi avaliar a resistência de união de seis adesivos experimentais contendo sistemas fotoiniciadores binários ou ternários, associados a três diferentes concentrações de MDP (0-12% em peso) após 12 meses de armazenamento em água destilada. Material e Métodos: Adesivos experimentais foram preparados com: bis-GMA, UDMA, bis-EMA, TEGDMA, HEMA, BHT e etanol, contendo sistemas fotoiniciadores binários (CQ/amina) ou ternários (CQ/amina/DPIHFP ­ 0,5% em peso). Foi adicionado a esta composição 0%, 6% ou 12% em peso de MDP. Os sistemas adesivos foram aplicados seguindo o protocolo com condicionamento ácido. Moldes cilíndricos transparentes foram colocados sobre a dentina hibridizada, preenchidos com resina composta e fotopolimerizados. Os corpos-de-prova foram armazenados em água destilada a 37oC por 24h ou 12 meses e submetidos ao ensaio de microcisalhamento (n=6). Os dados foram analisados por ANOVA de três fatores e teste de Tukey (α=5%). Resultados: Para o sistema binário, após 12 meses de armazenamento, todos os valores de resistência de união foram semelhantes. Em relação à degradação da resistência de adesão ao longo do tempo, as formulações de MDP de 6% e 12% mostraram resistência de união mais estável do que 0% de MDP. Para o sistema ternário, todas as formulações (0%, 6% e 12% em massa de MDP) mostraram resistência de união estável em função do tempo. Conclusão: Para o sistema binário, as concentrações de 6 e 12% em massa de MDP foram capazes de manter a resistência de união em função do tempo, enquanto que para o sistema ternário, a estabilidade de união foi obtida independentemente da concentração de MDP. Pode-se concluir que, para a formulação dos adesivos utilizados neste estudo, independente do sistema fotoiniciador, a concentração de 12% MDP apresentou valores de resistência de união mais estáveis após 12 meses de armazenamento em água (AU)


Objective: The aim was to evaluate the bond strength of six experimental adhesives containing binary or ternary photoinitiator systems, associated with three different MDP concentrations (0-12wt%) after 12 months of storage in distilled water. Material and Methods: Experimental adhesives were prepared with: bis-GMA, UDMA, bis-EMA, TEGDMA, HEMA, BHT, and ethanol, containing binary (CQ/amine) or ternary (CQ/amine/DPIHFP (diphenyliodonium hexafluorophosphate) ­ 0.5wt%) photoinitiator systems. It was added to this composition 0wt%, 6wt%, or 12wt% of MDP. The adhesive systems were applied following the etch-and-rinse protocol. Transparent cylindrical molds were placed on the hybridized dentin, filled with composite resin and light-cured. The specimens were stored in distilled water at 37oC for 24h or 12 months and submitted to a microshear bond strength test (n=6). Data were analyzed by three-way ANOVA and Tukey's test (α=5%). Results: For the binary system, after 12 months of storage, all bond strength values were similar. Regarding bond strength degradation over time, 6wt% and 12wt% MDP formulations showed more stable bond strength than 0wt% MDP. For the ternary system, all formulations (0wt%, 6wt% and 12wt%) showed stable bond strength over time. Conclusion: For the binary photoinitiator system, the 6wt% and 12wt% MDP concentrations were able to keep bond strength stable over time, while for the ternary system, bond strength stability was achieved regardless the MDP concentration. (AU)


Assuntos
Cimentos Dentários , Fotoiniciadores Dentários
4.
Rev. Fac. Odontol. (B.Aires) ; 37(87): 25-33, 2022. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1537886

RESUMO

La Odontología Restauradora contemporánea no puede concebirse sin la adhesión de los materiales restauradores a las estructuras dentarias. En mu-chos procedimientos restauradores, no sólo el esmal-te sino también la dentina se encuentra involucrada, por lo tanto, la adhesión a esta última juega un rol cla-ve en el éxito clínico. No obstante, todavía supone un gran desafío lograr una adhesión estable y predeci-ble en el tiempo. El propósito del presente artículo es analizar las características principales de la dentina como sustrato adhesivo y describir los sistemas ad-hesivos actuales y sus mecanismos de acción (AU)


Contemporary Restorative Dentistry cannot be conceived without the adhesion of restorative materials to dental structures. In many restorative procedures not only the enamel, but also the dentin is involved, therefore dentin bonding plays a key role in their success. However, it is still a great challenge to achieve stable and predictable dentin bonding over time. The aim of this article is to analyze the main characteristics of dentin as an adhesive substrate and to describe current adhesive systems and their bonding mechanisms (AU)


Assuntos
Adesivos Dentinários/classificação , Dentina/efeitos dos fármacos , Dentina/ultraestrutura , Polímeros/classificação , Condicionamento Ácido do Dente/métodos , Desmineralização do Dente/fisiopatologia , Resinas Compostas/química , Metilmetacrilato/química , Restauração Dentária Permanente/tendências
5.
Artigo | IMSEAR | ID: sea-204983

RESUMO

Background: Use of zirconia in cosmetic dentistry has expanded which coincided with a new trend of adult orthodontics; therefore it is very important to find an accepted method and material of bonding orthodontic appliances affectively to zirconia surface. Materials and methods: The sample was composed of 30 monolithic zirconia crowns of the lower right first molar. All samples were treated first by sandblasting with aluminum oxide particle 50 μm, then they were divided into 3 equal groups (the 1st group was the control, while 2nd and 3rd were the test groups), containing 10 crowns each, according to the type of adhesive system used; conventional light cure orthodontic bonding system (TransbondTM XT Primer/ TransbondTM XT composite resin) was used in the control group, while 2 different (10-MDP)-containing adhesive systems (Single Bond Universal adhesive/ TransbondTM XT composite resin, TheraCem dual-cured self-adhesive resin cement) were used in the test groups, buccal tube of lower right first molar (Ortho-Cast M-Series, Dentaurum, Germany) was bonded on the buccal surface of each zirconia crown in all the groups using one of the adhesive systems. Results: The Single Bond Universal group had the highest mean value of shear bond strength (16.299 MPa), followed by TheraCem group (15.373 Mpa), while the control group had the least value (5.337 ± 1.274Mpa); however, a highly significant difference in the shear bond strength was found between control and Single Bond Universal, and control and TheraCem groups, while non-significant difference was found between Single Bond Universal and TheraCem groups. Conclusions: The two types of (10-MDP)-containing adhesive systems provide good value of shear bond strength for buccal tubes bonded to zirconia surface, however, Single Bond Universal adhesive/composite resin is the best.

6.
Rev. odontol. UNESP (Online) ; 48: e20190083, 2019. tab, graf
Artigo em Inglês | LILACS, BBO | ID: biblio-1043176

RESUMO

Abstract Introduction Modern dentistry is reflected in the insertion of new materials with different adhesion forms in dental structures, such as the Universal adhesive system. Objective To evaluate the bond strength of the universal dentin adhesive system, in the form of self-etching and conventional application, compared with a simplified conventional adhesive system, in two distinct periods: 1 week and 6 months. Material and method 48 bovine incisors separated into 6 groups, stored for 7 days, were selected. Worn out the buccal enamel until dentin exposure. Adper Single Bond 2 (3M Espe) or SingleBond Universal (3M Espe) adhesives were applied, and catheters filled with Opallis Flow (FGM) composite were placed. After photoactivation, the catheters were removed and the specimens (n ​​= 48), stored in distilled water at 37 °C for one week and six months, were exposed. The specimens were fixed to a universal testing machine (EMIC DL 2000) with a speed of 0.5 mm / min. Bond strength (BS) was calculated in MPa, and data were statistically analyzed by Anova and Tukey test at 5% significance level. Result For Adper Single bond, the BS was equivalent in the times tested; for Universal conventional and self-conditioning time influenced the BS, with a decrease in the results. At 1 week, all stickers were different from each other, with higher BS for Universal conventional mode, followed by universal self-etching mode and then Adper Single bond. Conclusion The best results were achieved with universal adhesive in conventional mode for both tested times.


Resumo Introdução A odontologia moderna é refletida na inserção de novos materiais com diferentes formas de adesão nas estruturas dentárias, como o sistema adesivo Universal. Objetivo Avaliar a resistência adesiva do sistema adesivo universal em dentina, na forma de aplicação auto condicionante e convencional, comparando com um sistema adesivo convencional simplificado, em dois períodos distintos: 1 semana e 6 meses. Material e método Foram selecionados 48 incisivos bovinos separados em 6 grupos, armazenados por 7 dias. Desgastado o esmalte vestibular, até exposição da dentina. Aplicaram-se os adesivos Adper Single Bond 2 (3M Espe) ou SingleBond Universal (3M Espe), e sobre este, posicionados cateteres preenchidos com o compósito Opallis Flow (FGM). Após fotoativação, removeram-se os cateteres e expuseram-se os corpos de prova (n=48), armazenados em água destilada a 37 °C por uma semana e seis meses. Os corpos de prova foram fixados uma máquina universal de ensaios (EMIC DL 2000), com velocidade de 0,5 mm/min. A resistência de união (RU) foi calculada em MPa, e os dados foram analisados estatisticamente pela Anova e pelo teste de Tukey ao nível de 5% de significância. Resultado Para Adper Single bond, a RU foi equivalente nos tempos testados; para Universal modo convencional e autocondicionante o tempo influenciou na RU, havendo um decréscimo nos resultados. Em 1 semana, todos os adesivos foram diferentes entre si, com maior RU para Universal modo convencional, seguido por universal modo autocondicionante e então pelo Adper Single bond. Conclusão O melhor desempenho foi do adesivo universal na forma convencional nos dois tempos testados.


Assuntos
Cimentos Dentários , Materiais Dentários , Métodos , Resistência ao Cisalhamento , Dentina
7.
Malaysian Journal of Medicine and Health Sciences ; : 194-197, 2019.
Artigo em Inglês | WPRIM | ID: wpr-821949

RESUMO

@#Metastasis is a process of tumour cells escaping from the primary site and form a new lesion in other organs. It is a common phenomenon where bone is the frequent metastatic site. Bone scan using 99m-Techetium-Methylenediphosphate (99mTc-MDP) is used to diagnose bone pathologies such as bone metastases. 99mTc-MDP specifically binds to calcium which present in bone. This study aimed to validate 99mTc-MDP in breast cancer-induced to bone rat model and to determine calcium presence in the progression of metastasis. The rats were divided into two groups (normal and cancer-induced groups). For cancer-induced group, the left femur was induced with breast cancer cell line, MDA-MB-231. After 21 days, all rats were subjected to SPECT-CT scan. Our finding suggests that the kidney uptake of 99mTc-MDP is due to the calcium crystal presence caused by hypercalcemia. This is only a preliminary data, and further analysis will be conducted.

8.
Korean Journal of Nuclear Medicine ; : 349-355, 2019.
Artigo em Inglês | WPRIM | ID: wpr-786488

RESUMO

The authors present two cases in which the ruptured popliteal (Baker's) cysts remained undetected and were diagnosed only during an isotope investigation. The aim was to describe a specific imaging sign, the “arch sign”, that is indicative of ruptured Baker's cysts. In both cases, the whole-body imaging was performed 2 hours after injection of 706.7 MBq of Tc-99m-MDP. Single-photon emission computed tomography (SPECT) imaging was performed to localize an accumulation of the radiopharmaceutical. An analysis of literature was performed to connect these cases with previously reported data and to detect the pathognomonic radio image sign of ruptured popliteal cysts. The arch-shaped distribution of the radiopharmaceutical below the knee joints was seen already on the whole-body bone scan image in both cases. An anterior view of SPECT MIP images showed the arched accumulation of the Tc-99m-MDP bone tracer along the postero-medial aspect of the right calf secondary to synovial fluid leak from a ruptured Baker's cyst. The similar arthroscintigrams were published since 1971 without recognizing this sign as pathognomonic. Tc-99m-MDP bone scanning is sensitive for a Baker's cyst with synovial effusion, and distribution of a radiopharmaceutical in the medial posterior calf in a shape of an arch, the arch sign, may serve as an indicator of a ruptured popliteal cyst.


Assuntos
Articulação do Joelho , Cisto Popliteal , Líquido Sinovial , Tomografia Computadorizada de Emissão , Tomografia Computadorizada de Emissão de Fóton Único
9.
Korean Journal of Nuclear Medicine ; : 278-286, 2019.
Artigo em Inglês | WPRIM | ID: wpr-786480

RESUMO

PURPOSE: To investigate the correlation between the tenosynovitis pattern on two-phase bone scintigraphy (2P-BS) and clinical manifestation in patients with suspected rheumatoid arthritis (RA).METHOD: 2P-BS including technetium-99m-methylene diphosphonate blood pool and bone phase imaging in 402 consecutive patients with clinically suspected RAwere retrospectively reviewed. According to 2010 RA Classification Criteria, patients were grouped as RA and non-RA. Visual assessment of all fingers, toes, wrists, and ankles on 2P-BS was performed. Clinical suspected tenosynovitis was evaluated on physical examination. Rheumatoid factor, anti-cyclic citrullinated protein antibody, C-reactive protein, and estimated sedimentation rate were obtained. Radiographic findings were also used to define early and established arthritis.RESULTS: Tenosynovitis pattern was detected in 12.7%(51/402 patients) on 2P-BS.A total of 94.1%(48/51) were diagnosed as RA vs. 5.9% (3/51) as non-RA. Of the 48 RA patients with positive 2P-BS finding, 85.4% (41/48) had early arthritis and 14.6% (7/48) had established arthritis. On physical examination, tenosynovitis was suspected in 21.9% (88/402). A total of 56.8% (50/88) belonged to the RA group and 43.2% (38/88) to the non-RA group. The tenosynovitis pattern of 2P-BS and physical examination showed statistical difference and moderate agreement. The positive tenosynovitis pattern on 2P-BS represented up to 26.408 of odds ratio which was highest among the RA-associated factors.CONCLUSION: Tenosynovitis pattern on 2P-BS was more commonly detected in the RA group and was more frequently associated with early arthritis pattern. Therefore, 2P-BS could give additional information for the detection of subclinical tenosynovitis in early or preclinical RA patients.


Assuntos
Humanos , Tornozelo , Artrite , Artrite Reumatoide , Proteína C-Reativa , Classificação , Dedos , Métodos , Razão de Chances , Exame Físico , Cintilografia , Estudos Retrospectivos , Fator Reumatoide , Tenossinovite , Dedos do Pé , Punho
10.
Chinese Journal of Radiological Medicine and Protection ; (12): 629-634, 2019.
Artigo em Chinês | WPRIM | ID: wpr-755021

RESUMO

Objective To study the radiation level in the surrounding of patients undergoing 99Tcm-MDP SPECT bone imaging and associated influencing factors and provide experimental data for the radiation safety of personnel around the patients.Methods A total of 367 patients undergoing whole-body bone imaging in Cancer Hospital,Chinese Academy of Medical Sciences were investigated to measure the ambient dose equivalent rate around the patients at different time and different distances from the patients,analyze the variations of ambient dose equivalent rate with time and distances,estimate the dose level at different distances around the patients,and evaluate the radiation dose to personnel around the patients.Results The ambient dose equivalent rate around the patient decreased exponentially with time;the effective half-life of 99Tcm in patients' body increased with time.The ambient dose equivalent rate varied by power function with increasing distance within 4 meters from the patient with the mean power value of -1.45.The radiation levels were 238.3 μSv at 0.5 m,99.7 μSv at 1 m,and 61.8 μSv at 1.5 m from the patient undergoing 99Tcm injection to its vanishing in patients' body.At different time points,the radiation doses at 0.5 m off the patient for 10 min were:9.9,3.0,1.9 μSv at 0,3 and 6 h,respectively.Conclusions The ambient dose equivalent rate around the patients undergoing 99Tcm-MDP SPECT bone imaging decrease rapidly with increasing time and distance.The patients can cause a certain degree of exposures to the surrounding personnel,but the exposure level is far lower than the relevant national standards.It is suggested that the patients should not receive other types of diagnosis and treatments spending lot of time and in close contact with medical staff while bone imaging being conducted on the same day.

11.
Braz. dent. j ; 29(3): 275-281, May-June 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951546

RESUMO

Abstract This study evaluated the effectiveness of a multi-mode adhesive (SBU-Scotch Bond Universal/3M) as a substitute for silica coating and silane application on the bonding of zirconia ceramics to resin cement. One-hundred and twenty sintered zirconia ceramic blocks (5 x 5 x 5 mm) were obtained, finished by grounding with silicon carbide paper (#600, #800, #1000 and #1200) and randomly divided into 12 groups (n=10) in accordance with the factors "surface treatment" (ScSi - silicatization + silanization; ScSBU - silicatization + SBU; SBU - SBU without photoactivation and SBUp - SBU photoactivated) and "ceramic" (Lava / 3M ESPE, Ceramill Zirconia / Amann Girrbach and Zirkonzahn / Zirkonzahn). Dual resin cement cylinders (RelyX Ultimate/3M ESPE) were subsequently produced in the center of each block using a silicon matrix (Ø=2 mm, h=5 mm) and photoactivated for 40 s (1200 mW/cm2). The samples were stored for 30 days in distilled water (37ºC) and submitted to shear bond strength test (1 mm/min, 100 KgF). Data (MPa) were analyzed under ANOVA (2 levels) and Tukey test (5%). Complementary analyzes were also performed. ANOVA revealed that only the factor "surface treatment" was significant (p=0.0001). The ScSi treatment (14.28A) promoted statistically higher bond strength values than the other ScSBU (9.03B), SBU (8.47B) and SBUp (7.82B), which were similar to each other (Tukey). Failure analysis revealed that 100% of the failures were mixed. The silica coating followed by the silanization promoted higher bond strength values of resin cement and ceramic, regardless of the zirconia ceramic or SBU.


Resumo Este estudo avaliou a efetividade de um adesivo "multi-mode" (Single Bond Universal/3M) como um substituto para a silicatização e aplicação do silano na resistência de união das cerâmicas de zircônia e um cimento resinoso. Para isso, 120 blocos cerâmicos sinterizados de zircônia nas dimensões de (5 x 5 x 5 mm) foram obtidos, lixados com lixas de granulação decrescente (#600, #800, #1000 e #1200) e divididos aleatoriamente em 12 grupos (n = 10), de acordo com os fatores "tratamento de superfície" (ScSi - silicatização + silanização; ScSBU - silicatização + Single Bond; SBU - SBU sem fotoativação e SBUp - SBU com fotoativação) e "cerâmica" (Lava/3M ESPE, Ceramill Zircônia/ Amann Girrbach e Zirkonzahn/Zirkonzahn). Posteriormente, cilindros de cimento resinoso dual (RelyX Ultimate/3M ESPE) foram confeccionados no centro de cada bloco com auxílio de uma matriz de silicone (Ø=2 mm; h=5 mm) e fotopolimerizados por 40 s (1200 mW/ cm²). Em seguida, as amostras foram armazenadas durante trinta dias em água destilada (37 °C) e submetidas ao ensaio de resistência de união ao cisalhamento (1 mm/min, 100 kgF). Os dados (MPa) foram analisados sob ANOVA (2 fatores) e teste de Tukey (5%). Análises complementares também foram realizadas. ANOVA revelou que apenas o fator "tratamento de superfície" foi significativo (p=0,0001). O tratamento ScSi (14.28A) promoveu valores de adesão estatisticamente superiores aos demais ScSBU (9.03B), SBU (8.47B) e SBUp (7.82B), os quais foram semelhantes entre si (Tukey). A Análise de falhas revelou que 100% da falhas que ocorreram foram mistas. A silicatização seguida da silanização promoveu a melhor resistência de união entre cimento resinoso e a cerâmica, independentemente do tipo da cerâmica ou do SBU.


Assuntos
Silanos/química , Ítrio , Zircônio , Silicatos/química , Cimentos Dentários , Espectrometria por Raios X , Resistência à Tração , Difração de Raios X , Colagem Dentária , Molhabilidade , Cimentos de Resina/química , Análise de Falha de Equipamento , Resistência ao Cisalhamento , Análise do Estresse Dentário
12.
The Journal of Advanced Prosthodontics ; : 374-380, 2018.
Artigo em Inglês | WPRIM | ID: wpr-742054

RESUMO

PURPOSE: The effect of silica-based glass-ceramic liners on the tensile bond strength between zirconia and resin-based luting agent was evaluated and compared with the effect of 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-containing primers. MATERIALS AND METHODS: Titanium abutments and zirconia crowns (n = 60) were fabricated, and the adhesive surfaces of the specimens were treated by airborne-particle abrasion. The specimens were divided into 5 groups based on surface treatment: a control group, 2 primer groups (MP: Monobond Plus; ZP: Z Prime Plus), and 2 liner groups (PL: P-containing Liner; PFL: P-free Liner). All specimens were cemented with self-adhesive resin-based luting agent. After 24-hour water storage and thermocycling (5,000 cycles, 5℃/55℃), the tensile bond strength was measured using a universal testing machine. Failure mode analysis and elemental analysis on the bonding interface were performed. The data were analyzed using Kruskal-Wallis test, Dunn's post hoc test, and Fisher's exact test. RESULTS: The liner groups and primer groups showed significantly higher tensile bond strengths than that of the control group (P < .05). PFL showed a significantly higher tensile bond strength than the primer groups (P < .05). The percentage of mixed failure was higher in the primer groups than in the control group (P < .001), and all the specimens showed mixed failure in the liner groups (P < .001). A chemical reaction area was observed at the bonding interface between zirconia and liner. CONCLUSION: The application of liner significantly increased the tensile bond strength between zirconia and resin-based luting agent. PFL was more effective than MDP-containing primers in improving the tensile bond strength with the resin-based luting agent.


Assuntos
Adesivos , Coroas , Cimentos Dentários , Titânio , Água
13.
The Journal of Advanced Prosthodontics ; : 308-314, 2018.
Artigo em Inglês | WPRIM | ID: wpr-742044

RESUMO

PURPOSE: Plasma activation of hydrophobic zirconia surfaces might be suitable to improve the bond strength of luting materials. The aim of this study was to analyze the influence of nonthermal argon-plasma on the shear bond strength (SBS) between zirconia and different combinations of 10-MDP adhesive systems and luting composites after artificial aging. MATERIALS AND METHODS: Two hundred forty Y-TZP specimens were ground automatically with 165 µm grit and water cooling. Half of the specimens received surface activation with nonthermal argon-plasma. The specimens were evenly distributed into three groups according to the adhesive systems ([Futurabond U, Futurabond M, Futurabond M + DCA], VOCO GmbH, Germany, Cuxhaven) and into further two subgroups according to the luting materials ([Bifix SE, Bifix QM], VOCO GmbH). Each specimen underwent artificial aging by thermocycling and water storage. SBS was measured in a universal testing machine. Statistical analysis was performed using ANOVA and Scheffè procedure with the level of significance set to 0.05. RESULTS: Surface activation with nonthermal plasma did not improve the bond strength between zirconia and the tested combinations of adhesive systems and luting materials. The plasma-activation trended to reveal higher bond strength if the self-etch luting material (Bifix SE) was used, irrespective of the adhesive system. CONCLUSION: Plasma-activation seems to be suitable to improve bond strength between zirconia and self-etch resin materials. However, further research is necessary to identify the influence of varying plasma-parameters.


Assuntos
Adesivos , Envelhecimento , Argônio , Alemanha , Plasma , Água
14.
The Journal of Advanced Prosthodontics ; : 205-210, 2018.
Artigo em Inglês | WPRIM | ID: wpr-742035

RESUMO

PURPOSE: The purpose of this study was to evaluate the efficiency of a gas-phase fluorination method under different fluorination periods through using two resin cements. MATERIALS AND METHODS: 84 zirconia specimens in dimensions of 5 mm × 5 mm × 2 mm were prepared and surface treated with 50 µm aluminum oxide particles or gas phase fluorination for 2 min, 5 min, or 10 min. One specimen in each group was surface analyzed under scanning electron microscope. The remaining specimens were bonded to composite cylinders in dimensions of 2 mm diameter and 3 mm high with Panavia SA Plus or Variolink N. Then, the specimens were stored in 37℃ distilled water for 24 hours and shear bond strength test was applied at a speed of 1 mm/min. RESULTS: The highest shear bond strength values were observed in the samples fluorinated for 5 minutes and cemented with Panavia SA Plus. Variolink N did not elicit any statistical differences between surface treatments. Panavia SA Plus resin cement and Variolink N resin cements featured statistically significant difference in shear bond strength values only in the case of 5 minutes of fluorination treatment. CONCLUSION: According to the results of this study, application of 5 minutes of fluorination with 10-methacryloyloxydecyl dihydrogen phosphate monomer (MDP) containing Panavia SA Plus resin cement increased the resin bond strength of zirconia. Fluorination of the zirconia surface using conventional resin cement, Variolink N, did not lead to an increase in bond strength.


Assuntos
Óxido de Alumínio , Cerâmica , Halogenação , Técnicas In Vitro , Métodos , Cimentos de Resina , Água
15.
Restorative Dentistry & Endodontics ; : e19-2018.
Artigo em Inglês | WPRIM | ID: wpr-714383

RESUMO

OBJECTIVES: This study investigated the effect of continuous application of 10-methacryloyloxydecyldihydrogen phosphate (MDP)-containing primer and luting resin cement on bond strength to tribochemical silica-coated yttria-stabilized tetragonal zirconia polycrystal (Y-TZP). MATERIALS AND METHODS: Forty bovine teeth and Y-TZP specimens were prepared. The dentin specimens were embedded in molds, with one side of the dentin exposed for cementation with the zirconia specimen. The Y-TZP specimen was prepared in the form of a cylinder with a diameter of 3 mm and a height of 10 mm. The bonding surface of the Y-TZP specimen was sandblasted with silica-coated aluminium oxide particles. The forty tribochemical silica-coated Y-TZP specimens were cemented to the bovine dentin (4 groups; n = 10) with either an MDP-free primer or an MDP-containing primer and either an MDP-free resin cement or an MDP-containing resin cement. After a shear bond strength (SBS) test, the data were analyzed using 1-way analysis of variance and the Tukey test (α = 0.05). RESULTS: The group with MDP-free primer and resin cement showed significantly lower SBS values than the MDP-containing groups (p < 0.05). Among the MDP-containing groups, the group with MDP-containing primer and resin cement showed significantly higher SBS values than the other groups (p < 0.05). CONCLUSIONS: The combination of MDP-containing primer and luting cement following tribochemical silica coating to Y-TZP was the best choice among the alternatives tested in this study.


Assuntos
Cimentação , Dentina , Fungos , Cimentos de Resina , Dióxido de Silício , Dente
16.
Chinese Journal of Oncology ; (12): 133-137, 2017.
Artigo em Chinês | WPRIM | ID: wpr-808232

RESUMO

Objective@#To analyze the clinical value of SPECT/CT in diagnosis of skull base bone invasion and clinical decision-making for nasopharyngeal carcinoma (NPC), and to compare their diagnostic value with SPECT/CT, CT, MRI, and MRI combined with SPECT (MRI-SPECT) for skull base bone invasion.@*Methods@#Before treatment, among 348 newly diagnosed NPC patients, CT scan was performed in 186 patients (group A) and the remaining 162 patients received MRI scan (group B). Clinical doctors then made clinical management decisions according to the CT or MRI results. After that, all patients underwent 99Tcm-MDP SPECT/CT examination for nasopharyngeal local tomography, and the results were provided to the clinical doctors to make clinical management decisions again. The changes between the two clinical management decisions were scored according to diagnosis, range of lesion, staging, treatment regimens, and auxiliary examination. The diagnostic value of CT scan, MRI scan, SPECT/CT and MRI-SPECT for skull base bone invasion was then evaluated and compared.@*Results@#In terms of changes in scores of clinical management decisions, the score of group A was 1.387 and group B was 0.951, showing a significant difference between the two groups by Wilcoxon test (Z=6.570, P<0.001). By χ2 test, there were correlations between CT and SPECT/CT (χ2 =98.495, P<0.001), and between MRI and SPECT/CT (χ2 =32.662, P<0.001). The consistency of CT and SPECT/CT (Kappa=0.713) was greater than MRI and SPECT (Kappa=0.449). The sensitivity of CT, MRI, SPECT/CT and MRI-SPECT was 67.1%, 84.5%, 90.8% and 100%, the specificity was 73.3%, 92.3%, 85.6% and 84.6%, and the area under the ROC curve was 0.702, 0.884, 0.882 and 0.923, respectively.@*Conclusions@#SPECT/CT has important impact on clinical management decision for NPC. In the judgement of skull base invasion, the diagnostic value of SPECT/CT is significantly higher than CT and approximately equal to MRI. SPECT/CT should be one of the routine examination methods of nasopharyngeal carcinoma. In addition, in view of its greater diagnostic value, MRI combined with SPECT should be the focus of future imaging studies.

17.
Korean Journal of Nuclear Medicine ; : 40-48, 2017.
Artigo em Inglês | WPRIM | ID: wpr-786902

RESUMO

PURPOSE: To identify differences between three-phase bone scan and SPECT/CT (TBS) and WBC SPECT/CT (WS) and compare diagnostic accuracies of each modality in patients with suspicious post-traumatic osteomyelitis (OM).METHODS: Twenty-one patients with suspicious post-traumatic OM were enrolled. All patients performed TBS and WS within 1 week. Foci ofMDP andWBC accumulation were divided into three categories: bone (OM), soft tissue (soft tissue inflammation; STI), negative for inflammation (NI). Confirmative diagnosis was made upon operative pathology or long-term clinical follow-up.RESULTS: Of 21 patients, four OM, eight STI, nine NI were finally diagnosed. TBS diagnosis was correct in three of four positive cases and nine of 17 negative cases. Sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV) of TBS were 75 %, 52.9 %, 57.1 %, 27.3 %, 90 %. WS diagnosis was correct in two of four positive cases and 17 of 17 negative cases. Sensitivity, specificity, accuracy, PPV, NPV were 50 %, 100 %, 81.0 %, 100 %, 89.5 %. Twelve of 21 cases showed agreement between TBS and WS. TBS misdiagnosed nine cases (six STI and two NI as eight OM; one OM as one STI), while WS misdiagnosed four cases (two OM as two STI; two STI as two NI). Combining results from TBS and WS led to better diagnostic accuracy (91.7 %) than either TBS or WS alone.CONCLUSION: TBS and WS showed moderate agreement in assessment of clinically suspected post-traumatic OM. WS better evaluated inflammation than TBS. WS tended to underestimate inflammation whereas TBS tended to overestimate inflammation. Combining TBS and WS enhanced diagnostic accuracy.


Assuntos
Humanos , Diagnóstico , Diagnóstico Diferencial , Seguimentos , Inflamação , Osteomielite , Patologia , Sensibilidade e Especificidade , Infecções Sexualmente Transmissíveis
18.
Chinese Journal of Nuclear Medicine and Molecular Imaging ; (6): 516-520, 2016.
Artigo em Chinês | WPRIM | ID: wpr-505239

RESUMO

Objective To summarize the SPECT/CT manifestation of spondylitis caused by Brucells infection and to evaluate the diagnostic value.Methods From June 2012 to October 2015,a total of 28 patients (14 males,14 females,average age 46.4 years) with Brucellosis spondylitis confirmed by laboratory test and pathology were included.The images of whole-body bone scan and SPECT/CT fusion imaging were retrospectively analyzed.According to the pathological and serologic test results,the diagnostic efficacy of imaging was calculated.x2 test was used.Results Most of the Brucellosis spondylitis happened in the lumbar(76.7%,43/56),and the most common locations were L3,L4,L5 (72.1%,31/43).Two or more involved consecutive vertebra were found in 71.4% (20/28) of the patients.Moderate radioactive distribution was showed in 89.2% (50/56) of lesions,high radioactive distribution was showed in 5.4% (3/56) of lesions,and mild radioactive distribution was showed in the rest 3 lesions.Thirty-three lesions(58.9%,33/56) had diffuse increased radioactivity uptake in the affected vertebra,and 32.1%(18/56) showed diffuse increased radioactivity at the superior and inferior margin of the vertebra;only 8.9% (5/56) of lesions were on one side of the vertebral bodies.The SPECT/CT results were as follows:(1) Bone destruction was showed in 80.4% (45/56) of lesions,and the edge of the lesion was clear.(2) For 66.7% (30/45) of lesions,bone hyperplasia was seen along with bone destruction and moderate radioactivity concentration on the edge of destruction area.(3) The damage of the intervertebral disc was mild,and the vertebral abscess was relatively rare (5.4%,3/56).The diagnostic accuracy of SPECT/CT was statistically higher than that of whole-body bone scan:67.8%(38/56) vs 96.2%(54/56);x2=13.1,P<0.05.Conclusion SPECT/CT imaging has a higher diagnostic efficiency than whole-body bone scan in Brucellosis spondylitis.

19.
Chinese Journal of Nuclear Medicine and Molecular Imaging ; (6): 454-457, 2016.
Artigo em Chinês | WPRIM | ID: wpr-502372

RESUMO

Objective To observe the antioxidant effects of 99Tc-MDP on the brain of aged mice induced by D-galactose.Methods A total of 48 healthy female Kunming mice were divided into 6 groups by random number table method:normal control group,model group,vitamin E (Vit E) group,groups treated with low,middle and high dosages of 99Tc-MDP.Except the normal control group,mice of each group were injected with 10% D-galactose saline subcutaneously in the neck for 42 d.At the same time,the 99Tc-MDP groups were given different dosages of 99Tc-MDP (1.75× 10-5,3.50× 10-5,0.70× 10-4 μg/g according to the body mass) respectively into abdominal cavity twice a day.Vit E group was given Vit E by intragastric administration from the first day.The model group was injected with saline every day.After behavioral testing,mice serum samples and brain tissue samples were collected for the determination of superoxide dismutase (SOD),malondialdehyde (MDA),glutathione peroxidase (GSH-Px) and monoamine oxidase (MAO)levels.Then the mice were sacrificed and the brain tissue was taken for HE staining.The independent-sample t test was used for data analysis.Results The mice model was established successfully.SOD levels in brain tissue of groups injected with low,middle,high dosages of 99Tc-MDP,Vit E group were (19.06± 6.44),(20.41±4.02),(22.24±3.76),(24.71±5.09) U/mgprot,respectively,all of which were higher than that of the model group((11.32±2.90) U/mgprot;t=3.099 6-6.504 6,P<0.05 or <0.01).There were similar results for GSH-Px (t =2.214 1-4.145 7,P<0.05 or <0.01).MDA and MAO levels in brain tissue of 99Tc-MDP groups were lower than those of the model group (t =2.140 3-3.057 8,all P<0.05).Compared to normal control group,the hippocampus in model group showed reduced cell number and layers,disordered structure,with part of the cells in smaller volume and abnormal nuclear shape.In Vit E group and the three 99Tc-MDP groups,no significant change of neuron was observed compared with normal control group,the degeneration and necrosis of hippocampal cells were mild compared with model group,the cell number and morphology were normal,and the structures were clear.Conclusion 99Tc-MDP may increase the activities of SOD,GSH-Px and reduce the levels of MDA and MAO in brain tissue of aged mice,thus it may be helpful in delaying the brain aging.

20.
Chinese Journal of Nuclear Medicine and Molecular Imaging ; (6): 250-254, 2016.
Artigo em Chinês | WPRIM | ID: wpr-496622

RESUMO

Objective To investigate the added value of CTAC for improving image quality and diagnostic efficiency of bone imaging in SPECT/CT.Methods Seventy-five patients (47 males,28 females,(56.6± 12.8) years) with abnormal uptake in planar whole-body bone scintigraphy underwent SPECT/CTfor differentiation of malignant from benign spinal lesions.NAC and CTAC SPECT images were classified based on 5-point scale (5:excellent,4:good,3:adequate,2:suboptimal,1:inadequate).The diagnostic confidence for both NAC and CTAC SPECT images were classified based on 4-point scale (4:definite,3:certain,2:equivocal,1:uninterpretable).The pathological results after surgery were used as gold standard to evaluate the added diagnostic value of CTAC for spinal lesions.Wilcoxon-signed rank sum test was used for data analysis.Results CTAC improved the image quality in 37.3% (28/75) of patients,and downgraded in 2.7% (2/75) of patients.The remaining 45 patients were unchanged (60.0%,45/75).SPECT with CTAC could significantly improve the image quality (z=-4.747,P<0.001),but the overall diagnostic confidence was not increased (z=-1.000,P>0.05).Conclusion CTAC can improve the image quality of spinal SPECT,especially useful in imaging with poorer quality,but it has no significant incremental value in diagnostic confidence.

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