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1.
Braz Oral Res ; 34: e004, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32022223

RESUMO

The aim of this study was to analyze the structural, morphological and mechanical properties of two different lithium disilicate glass-reinforced ceramics for CAD-CAM systems (IPS e.max CAD and Rosetta SM). Five methodologies were used for both ceramics: microstructure (n = 2) was analyzed using x-ray diffraction (XRD); morphological properties (n = 2) were analyzed by scanning electron microscopy (SEM), with and without hydrofluoric etching; porosity (n = 3) was assessed using 3D micro-computed tomography (micro-CT); flexural strength was measured (n =1 0) using the three-point bending test; and bond strength was determined with self-adhesive resin cement (n = 10), using a microshear bond test. After performing all the tests, the data were analyzed using t-Student test and two-way ANOVA. All the tests used a significance level of α = 0.05. High peak positions corresponding to standard lithium metasilicate and lithium disilicate with similar intensities were observed for both ceramics in the XRD analysis. Morphological analysis showed that the crystalline structure of the two ceramics studied showed no statistical difference after acid etching. Additionally, no significant differences were recorded in the number or size of the pores for the ceramics evaluated. Moreover, no differences in flexural strength were found for the ceramic materials tested, or in the bond strength to ceramic substrates for the resin cements. Based on the study results, no significant differences were found between the two CAD-CAM lithium disilicate glass-reinforced ceramics tested, since they presented similar crystalline structures with comparable intensities, and similar total porosity, flexural strength and bond strength.


Assuntos
Cerâmica/química , Projeto Auxiliado por Computador , Porcelana Dentária/química , Vidro/química , Análise de Variância , Colagem Dentária/métodos , Resistência à Flexão , Teste de Materiais , Microscopia Eletrônica de Varredura , Porosidade , Valores de Referência , Reprodutibilidade dos Testes , Cimentos de Resina/química , Resistência ao Cisalhamento , Propriedades de Superfície , Difração de Raios X
2.
Braz Dent J ; 28(5): 624-631, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29215689

RESUMO

The aim of this study was to evaluate the degree of conversion, color stability, chemical composition, and bond strength of a light-cured resin cement contaminated with three different hemostatic solutions. Specimens were prepared for the control (uncontaminated resin cement) and experimental groups (resin cement contaminated with one of the hemostatic solutions) according to the tests. For degree of conversion, DC (n = 5) and color analyses (n = 10), specimens (3 mm in diameter and 2 mm thick) were evaluated by Fourier transform infrared spectroscopy (FTIR) and CIELAB spectrophotometry (L*, a*, b*), respectively. For elemental chemical analysis (n = 1), specimens (2 mm thick and 6 mm in diameter) were evaluated by x-ray energy-dispersive spectroscopy (EDS). The bond strengths of the groups were assessed by the microshear test (n = 20) in a leucite-reinforced glass ceramic substrate, followed by failure mode analysis by scanning electron microscopy (SEM). The mean values, except for the elemental chemical evaluation and failure mode, were evaluated by ANOVA and Tukey's HSD test. The color stability was influenced by storage time (p<0.001) and interaction between contamination and storage time (p<0.001). Hemostop and Viscostat Clear contamination did not affect the DC, however Viscostat increased the DC. Bond strength of the resin cement to ceramic was negatively affected by the contaminants (p<0.001). Contamination by hemostatic agents affected the bond strength, degree of conversion, and color stability of the light-cured resin cement tested.


Assuntos
Hemostáticos , Cimentos de Resina/química , Cor , Microscopia Eletrônica de Varredura , Soluções , Análise Espectral , Propriedades de Superfície
3.
Braz. j. oral sci ; 16: e17070, jan.-dez. 2017. ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-883661

RESUMO

The aim of this study was to evaluate the presence of filling material in oval root canals after endodontic retreatment performed by different techniques, considering the area (mm2), location and root third using computed microtomography (µ-CT). Methods: Thirty human lower central incisor underwent biomechanical preparation, root filling and filling removal using two techniques (n=15): MN- manual retreatment technique (Gates Glidden burs and stainless steel manual files); and RT- rotary retreatment technique (ProTaper Universal and ProTaper Retreatment Systems). Cross-sectional images of the teeth were made using µ-CT to identify the presence of remaining filling in all root thirds of the canal walls. The remaining material detected in 150 µ-CT sections was identified and its area quantified (mm2) for each root third individually. Results: Data analysis showed no difference in the remaining area of filling material (p=0.8611) for the both techniques. Higher frequency of remaining material was verified in the lingual wall of the root canals. Regardless of the retreatment technique, the apical third showed lager areas of remaining filling material. More areas of remaining material were detected in the cervical third of the RT group, whereas for the MN group, most areas were observed in the middle and apical thirds. Conclusion: According to our results, no significant differences were verified between the efficiency of the rotary and manual techniques for removing filling material due to the interferences caused by the root canal anatomy (AU)


Assuntos
Humanos , Masculino , Feminino , Retratamento , Preparo de Canal Radicular , Microtomografia por Raio-X
4.
Braz. dent. j ; 28(5): 624-631, Sept.-Oct. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-888690

RESUMO

Abstract The aim of this study was to evaluate the degree of conversion, color stability, chemical composition, and bond strength of a light-cured resin cement contaminated with three different hemostatic solutions. Specimens were prepared for the control (uncontaminated resin cement) and experimental groups (resin cement contaminated with one of the hemostatic solutions) according to the tests. For degree of conversion, DC (n = 5) and color analyses (n = 10), specimens (3 mm in diameter and 2 mm thick) were evaluated by Fourier transform infrared spectroscopy (FTIR) and CIELAB spectrophotometry (L*, a*, b*), respectively. For elemental chemical analysis (n = 1), specimens (2 mm thick and 6 mm in diameter) were evaluated by x-ray energy-dispersive spectroscopy (EDS). The bond strengths of the groups were assessed by the microshear test (n = 20) in a leucite-reinforced glass ceramic substrate, followed by failure mode analysis by scanning electron microscopy (SEM). The mean values, except for the elemental chemical evaluation and failure mode, were evaluated by ANOVA and Tukey's HSD test. The color stability was influenced by storage time (p<0.001) and interaction between contamination and storage time (p<0.001). Hemostop and Viscostat Clear contamination did not affect the DC, however Viscostat increased the DC. Bond strength of the resin cement to ceramic was negatively affected by the contaminants (p<0.001). Contamination by hemostatic agents affected the bond strength, degree of conversion, and color stability of the light-cured resin cement tested.


Resumo O objetivo desse estudo foi avaliar o grau de conversão, estabilidade de cor, composição química e resistência de união de um cimento resinoso fotoativado contaminado com três soluções hemostáticas diferentes. Foram preparadas amostras para o grupo controle (cimento não contaminado) e grupos experimentais (cimento contaminado com uma das soluções hemostáticas) de acordo com os testes. Para o grau de conversão e análise de cor (n=10), as amostras (3 mm de diâmetro e 2 mm de espessura) foram avaliadas por espectroscopia de infravermelho com transformação de Fourier (FTIR) e espectrofotometria CIELAB (L*, A*, B*), respectivamente. Para a análise química elementar (n=1), os espécimes (2 mm de espessura e 6 mm de diâmetro) foram avaliados por espectroscopia de energia dispersiva de raios-x (EDS). As resistências de união dos grupos foram avaliadas pelo ensaio de microcisalhamento (n=20) em um substrato cerâmico de vidro reforçado com leucita, seguida da análise de modo de falha por microscopia eletrônica de varredura (MEV). Os valores médios, com exceção da avaliação química e do modo de falha, foram avaliados por ANOVA e pelo teste de Tukey. A estabilidade de cor foi influenciada pelo tempo de armazenagem (p<0,001) e interação entre a contaminação e o tempo (p<0,001). A contaminação pelo Hemostop e Viscostat Clear não influenciaram no GC, porém a contaminação com Viscostat aumentou o GC. A resistência de união do cimento a cerâmica foi negativamente afetada pelos contaminantes (p<0,001). A contaminação por agentes hemostáticos afetou a resistência de união, o grau de conversão e a estabilidade de cor do cimento resinoso fotoativado testado.


Assuntos
Hemostáticos , Cimentos de Resina/química , Cor , Microscopia Eletrônica de Varredura , Soluções , Análise Espectral , Propriedades de Superfície
5.
Braz Dent J ; 28(1): 16-23, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28301013

RESUMO

The aim of this study was to evaluate the µTBS in different dentin substrates and water-storage periods. Twenty-four dentin blocks obtained from sound third molars were randomly divided into 3 groups: Sound dentin (Sd), Caries-affected dentin (Ca) and Caries-infected dentin (Ci). Dentin blocks from Ca and Ci groups were subjected to artificial caries development (S. mutans biofilm). The softest carious tissue was removed using spherical drills under visual inspection with Caries Detector solution (Ca group). It was considered as Ci (softer and deeply red stained dentin) and Ca (harder and slightly red stained dentin). The Adper Single Bond 2 adhesive system was applied and Z350 composite blocks were built in all groups. Teeth were stored in deionized water for 24 h at 37 ºC and sectioned into beams (1.0 mm2 section area). The beams from each tooth were randomly divided into three storages periods: 24 h, 6 months or 1 year. Specimens were submitted to µTBS using EZ test machine at a crosshead speed of 1.0 mm/min. Failure mode was examined by SEM. Data from µTBS were submitted to split plot two-way ANOVA and Tukey's HSD tests (a=0.05). The µTBS (MPa) of Sd (41.2) was significantly higher than Ca (32.4) and Ci (27.2), regardless of storage. Ca and Ci after 6 months and 1 year, presented similar µTBS. Mixed and adhesive failures predominated in all groups. The highest µTBS values (48.1±9.1) were found for Sd at 24 h storage. Storage of specimens decreased the µTBS values for all conditions.


Assuntos
Cárie Dentária , Adesivos Dentinários , Dentina , Análise do Modo e do Efeito de Falhas na Assistência à Saúde , Técnicas In Vitro , Microscopia Eletrônica de Varredura , Dente Serotino , Resistência à Tração
6.
J Appl Oral Sci ; 25(1): 61-68, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28198977

RESUMO

Objective: The aim of this study was to assess the performance of resin cements when different curing modes are used, by evaluating the degree of conversion and bond strength to a ceramic substrate. Material and Methods: Three resin cements were evaluated, two dual-cured (Variolink II and RelyX ARC) and one light-cured (Variolink Veneer). The dual-cured resin cements were tested by using the dual activation mode (base and catalyst) and light-activation mode (base paste only). For degree of conversion (DC) (n=5), a 1.0 mm thick feldspathic ceramic disc was placed over the resin cement specimens and the set was light activated with a QTH unit. After 24 h storage, the DC was measured with Fourier transform infrared spectroscopy (FTIR). For microshear bond strength testing, five feldspathic ceramic discs were submitted to surface treatment, and three cylindrical resin cement specimens were bonded to each ceramic surface according to the experimental groups. After 24 h, microshear bond testing was performed at 0.5 mm/min crosshead speed until the failure. Data were submitted to one-way ANOVA followed by Tukey test (p<0.05). Scanning electron microscopy (SEM) was used for classifying the failure modes. Results: Higher DC and bond strength values were shown by the resin cements cured by using the dual activation mode. The Variolink II group presented higher DC and bond strength values when using light-activation only when compared with the Variolink Veneer group. Conclusion: The base paste of dual-cured resin cements in light-activation mode can be used for bonding translucent ceramic restorations of up to or less than 1.0 mm thick.


Assuntos
Silicatos de Alumínio/química , Bis-Fenol A-Glicidil Metacrilato/química , Cerâmica/química , Cura Luminosa de Adesivos Dentários/métodos , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Compostos de Potássio/química , Cimentos de Resina/química , Análise de Variância , Luzes de Cura Dentária , Teste de Materiais , Microscopia Eletrônica de Varredura , Processos Fotoquímicos , Polimerização , Valores de Referência , Reprodutibilidade dos Testes , Resistência ao Cisalhamento , Propriedades de Superfície , Fatores de Tempo
7.
Braz. dent. j ; 28(1): 16-23, Jan.-Feb. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-839124

RESUMO

Abstract The aim of this study was to evaluate the μTBS in different dentin substrates and water-storage periods. Twenty-four dentin blocks obtained from sound third molars were randomly divided into 3 groups: Sound dentin (Sd), Caries-affected dentin (Ca) and Caries-infected dentin (Ci). Dentin blocks from Ca and Ci groups were subjected to artificial caries development (S. mutans biofilm). The softest carious tissue was removed using spherical drills under visual inspection with Caries Detector solution (Ca group). It was considered as Ci (softer and deeply red stained dentin) and Ca (harder and slightly red stained dentin). The Adper Single Bond 2 adhesive system was applied and Z350 composite blocks were built in all groups. Teeth were stored in deionized water for 24 h at 37 ºC and sectioned into beams (1.0 mm2 section area). The beams from each tooth were randomly divided into three storages periods: 24 h, 6 months or 1 year. Specimens were submitted to µTBS using EZ test machine at a crosshead speed of 1.0 mm/min. Failure mode was examined by SEM. Data from µTBS were submitted to split plot two-way ANOVA and Tukey’s HSD tests (a=0.05). The µTBS (MPa) of Sd (41.2) was significantly higher than Ca (32.4) and Ci (27.2), regardless of storage. Ca and Ci after 6 months and 1 year, presented similar µTBS. Mixed and adhesive failures predominated in all groups. The highest µTBS values (48.1±9.1) were found for Sd at 24 h storage. Storage of specimens decreased the µTBS values for all conditions.


Resumo O objetivo neste estudo foi avaliar a resistência de união à microtração (RUµT) de um sistema adesivo convencional (Adper Single Bond 2 - SB) em diferentes substratos dentinários e períodos de armazenagem. Vinte e quatro blocos de dentina foram obtidos de terceiros molares hígidos e separados aleatoriamente em 3 grupos (n=8): dentina sadia (Ds), dentina afetada (Da) e dentina infectada (Di). A Da e a Di foram submetidas ao desenvolvimento biológico artificial de cárie (S. mutans). O tecido cariado amolecido foi removido usando broca esférica sob inspeção visual com a solução Caries Detector (grupo Da). Considerou-se como Di a dentina amolecida e fortemente pigmentada de vermelho e como Da, a dentina hígida e levemente pigmentada de vermelho. O sistema adesivo SB foi aplicado de acordo com as recomendações do fabricante e blocos da resina composta Z350 foram construídos (6 mm de altura). O conjunto (dente/bloco de resina) foi armazenado em água deionizada por 24 horas a 37 °C. Estes foram seccionados em palitos (1,0 mm2 de área), que foram separados aleatoriamente em 3 períodos de armazenagem: 24 horas, 6 meses e 1 ano. Os palitos foram submetidos ao ensaio de resistência de união à microtração na máquina EZ teste a uma velocidade de 1,0 mm/min. Dados de RUµT foram submetidos à Análise de Variância 2 fatores em esquema de parcela subdividida e ao teste de Tukey (a=0,05). Os valores de resistência (MPa) da Ds (41,2) foram significativamente maiores do que os da Da (32,4) e Di (27,2), independente do tempo de armazenagem. Di e Da, 6 meses e 1ano, apresentaram valores similares de resistência de união. As falhas adesivas e mistas foram predominantes para todos os grupos. Em conclusão, os maiores valores de RUµT (48,1±9,1) foram verificados para a Ds e 24 h de armazenagem. A armazenagem diminuiu os valores de RUµT para todas as condições.


Assuntos
Adesivos Dentinários , Cárie Dentária , Dentina , Resistência à Tração , Técnicas In Vitro , Microscopia Eletrônica de Varredura , Análise do Modo e do Efeito de Falhas na Assistência à Saúde , Dente Serotino
8.
J. appl. oral sci ; 25(1): 61-68, Jan.-Feb. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-841162

RESUMO

Abstract Resin cements have led to great advances in dental ceramic restoration techniques because of their ability to bond to both dental structures and restorative materials. Objective The aim of this study was to assess the performance of resin cements when different curing modes are used, by evaluating the degree of conversion and bond strength to a ceramic substrate. Material and Methods Three resin cements were evaluated, two dual-cured (Variolink II and RelyX ARC) and one light-cured (Variolink Veneer). The dual-cured resin cements were tested by using the dual activation mode (base and catalyst) and light-activation mode (base paste only). For degree of conversion (DC) (n=5), a 1.0 mm thick feldspathic ceramic disc was placed over the resin cement specimens and the set was light activated with a QTH unit. After 24 h storage, the DC was measured with Fourier transform infrared spectroscopy (FTIR). For microshear bond strength testing, five feldspathic ceramic discs were submitted to surface treatment, and three cylindrical resin cement specimens were bonded to each ceramic surface according to the experimental groups. After 24 h, microshear bond testing was performed at 0.5 mm/min crosshead speed until the failure. Data were submitted to one-way ANOVA followed by Tukey test (p<0.05). Scanning electron microscopy (SEM) was used for classifying the failure modes. Results Higher DC and bond strength values were shown by the resin cements cured by using the dual activation mode. The Variolink II group presented higher DC and bond strength values when using light-activation only when compared with the Variolink Veneer group. Conclusion The base paste of dual-cured resin cements in light-activation mode can be used for bonding translucent ceramic restorations of up to or less than 1.0 mm thick.


Assuntos
Silicatos de Alumínio/química , Bis-Fenol A-Glicidil Metacrilato/química , Cerâmica/química , Cura Luminosa de Adesivos Dentários/métodos , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Compostos de Potássio/química , Cimentos de Resina/química , Análise de Variância , Luzes de Cura Dentária , Teste de Materiais , Microscopia Eletrônica de Varredura , Processos Fotoquímicos , Polimerização , Valores de Referência , Reprodutibilidade dos Testes , Resistência ao Cisalhamento , Propriedades de Superfície , Fatores de Tempo
10.
Biosci. j. (Online) ; 32(4): 1110-1117, july/aug. 2016. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-965678

RESUMO

This study aimed to assess the efficiency of manual and rotary techniques for removing root filling material in endodontic treated canals and to evaluate the extrusion of debris via apical foramen. After access preparation, thirty human lower central incisors were instrumented, filled and divided into two groups (n=15): MNmanual retreatment technique; RT- rotary retreatment technique. The teeth were submitted to micro-computed tomographic scanning before and after the retreatment procedure, for quantifying the remaining filling material by relating the initial and final conditions. The analysis was conducted separately in all root thirds. The volume of material extruded through the apical foramen was also quantified. The data were statistically analyzed using t-test and two-way analysis of variance (ANOVA) at 5% of significance. No significant differences were detected between remaining filling material for the techniques evaluated (p=0.74), even considering the apical third only (p>0.75). Significant differences were found for the remaining filling material verified between the cervical third and middle/apical thirds, with lower values being observed at the cervical third for both groups (p<0.05). Apical extrusion of filling material was verified in seven specimens (2 from MN group and 5 from RT group). Both techniques showed similar performance for removing filling material from the root canal, considering the whole tooth or the root thirds independently. The apical extrusion of filling material observed was not sufficient to indicate which technique has increased tendency to induce more events during retreatments.


Este estudo objetivou avaliar a eficiência das técnicas manual e rotatória na remoção de material obturador de dentes tratados endodonticamente, além de verificar a extrusão de resíduos via forame apical. Após acesso endodôntico, trinta incisivos centrais inferiores humanos foram instrumentados, obturados e divididos em dois grupos (n=15): MN- técnica de retratamento manual; RT- técnica de retratamento rotatória. Os dentes foram submetidos à escaneamento micro-tomográfico previamente e após os procedimentos de retratamento para quantificação do remanescente de material obturador relacionando as condições inicial e final. Esta análise foi conduzida separadamente em todos os terços radiculares. O volume de material extruído via forame apical também foi quantificado. Os dados foram analisados estatisticamente por meio dos Testes T e de Análise de Variância em dois níveis com significância em 5%. Diferenças significantes não foram detectadas entre a quantidade de material remanescente para as duas técnicas avaliadas (p=0,74), mesmo considerando o terço apical separadamente (p>0.75). Diferenças significantes foram encontradas na quantidade de material remanescente verificado entre os terços cervical e médio/apical, com menores valores detectados no terço cervical para ambos os grupos (p<0.05). Extrusão apical de material obturador foi identificada em sete espécimes (2 do grupo MN e 5 do grupo RT). As duas técnicas avaliadas apresentaram desempenho similar na remoção do material obturador do canal radicular, considerando o dente como um todo ou os terços radiculares separadamente. A extrusão apical de material obturador verificada não foi suficiente para indicar qual técnica possui maior tendência de promover eventos durante o retratamento.


Assuntos
Obturação do Canal Radicular , Endodontia , Extrusão Ortodôntica , Microtomografia por Raio-X
11.
Braz Oral Res ; 292015.
Artigo em Inglês | MEDLINE | ID: mdl-26083093

RESUMO

The aim of this study was to evaluate the influence of the flexion angle of files on the decentralization of root canals during instrumentation. Fifteen lower incisors were instrumented with Protaper Universal files and radiographed in two directions (mesiodistal and buccolingual) before and after instrumentation with a #15 K-file in position for evaluating the flexion angle of files. The specimens were also scanned before and after instrumentation using micro-computed tomography to obtain the canal area and the distance from the center position of the file to the canal walls. Sections located 1.0 mm (end of the canal), 3.0 mm (apical third), 9.0 mm (middle third), and 15.0 mm (cervical third) from the apex were verified. After instrumentation, the flexion angles of files decreased by an average of 0.76º in the buccolingual direction and 1.92º in the mesiodistal direction (p < 0.001); the canal area increased by an average of 0.58, 0.37, 0.23 and 0.13 mm(2) from the cervical to the end of the root canal (p < 0.001). Non-instrumented areas were observed on the buccal and lingual walls, and effective action of files was determined on the mesial and distal walls. The sections from the end of the canal showed canal deviation toward the lingual wall, whereas the other sections showed deviation toward the buccal wall. The flexion angles of files influence the final shape of the root canal, resulting in file decentralization along the pathway of the canal.


Assuntos
Cavidade Pulpar/anatomia & histologia , Preparo de Canal Radicular/instrumentação , Anatomia Transversal , Instrumentos Odontológicos , Cavidade Pulpar/diagnóstico por imagem , Humanos , Incisivo/anatomia & histologia , Incisivo/diagnóstico por imagem , Odontometria , Valores de Referência , Estatísticas não Paramétricas , Microtomografia por Raio-X
12.
Biosci. j. (Online) ; 31(2): 657-662, mar./abr. 2015.
Artigo em Inglês | LILACS | ID: biblio-964123

RESUMO

Congenital tooth agenesis and tooth loss due to dental traumatism are some of the most common causes leading to rehabilitation of young patients with dental implants. The success of treating congenitally missing teeth with implant-supported prosthesis is no more guided only by osseointegration criteria. Nowadays the successful rehabilitation of these cases involves the adequate installation of dental implants with suitable prosthetic contour, color, and emergence profile closer to that found in natural dentition. Several treatment options are available for restoring patients with congenitally missing teeth such as maxillary lateral incisors. Fixed prosthodontics and orthodontics managements are considered acceptable treatment protocols. However, the gold standard rehabilitation of congenitally missing maxillary incisors is performed with implant-based prosthesis since no tooth wear neither extensive tooth movements are necessary. The present paper reports the treatment of a young adult woman with congenitally missing maxillary lateral incisors who underwent orthodontic treatment for improvement of teeth alignment and occlusal balance previous to dental implant surgery. This treatment also allowed appropriate space for the future lateral incisors crowns. Then, Morse-type conical implants were positioned and prosthetic abutments installed. Ceramic laminates were planned on central incisors in order to improve anterior aesthetics. All-ceramic crowns and laminates were made using lithium dissilicate-based ceramic (e-Max Press). The multidisciplinary association of orthodontic, implant and prosthetic techniques resulted in successful functional and aesthetic rehabilitation of the case, which was maintained after 1 year follow up.


Agenesias e perdas dentárias devido a traumatismos estão entre as principais causas de reabilitações de pacientes jovens com implantes dentários. O sucesso do tratamento de agenesias com implantes osseointegrados não se limita mais à osseointegração exclusivamente. Atualmente, o sucesso da reabilitação destes casos envolve a correta instalação de implantes que favoreçam a confecção de uma prótese com cor, forma e perfil de emergência o mais semelhante possível aos dentes naturais. Os cirurgiões-dentistas têm várias opções para tratar casos de agenesias como as de incisivos laterais superiores. Próteses fixas convencionais e movimentação ortodôntica são considerados protocolos de tratamento aceitáveis. Entretanto, agenesias de incisivos laterais superiores são reabilitadas satisfatoriamente com próteses sobre implantes uma vez que extensas movimentações ou desgastes dentários são necessários. O presente caso relata o tratamento de uma paciente jovem com agenesia dos incisivos laterais que havia feito tratamento ortodôntico para correção do posicionamento dentário e equilíbrio dental antes de se submeter à cirurgia para instalação de implantes. O tratamento ortodôntico também favoreceu a obtenção de espaço apropriado para instalação das coroas dos incisivos laterais. Posteriormente, implantes cônicos com plataforma protética tipo cone morse foram instalados e pilares selecionados. Laminados cerâmicos foram planejados para os incisivos centrais com objetivo de se promover um resultado final mais harmônico e estético. As coroas em cerâmica pura e laminados foram confeccionados com cerâmica a base de dissilicato de lítio (e.Max Press). A associação multidisciplinar entre tratamento ortodôntico, implantes e próteses sobre implantes resultou no sucesso funcional e estético da reabilitação do presente caso com acompanhamento clínico de uma ano.


Assuntos
Implantes Dentários , Osseointegração , Perda de Dente , Facetas Dentárias , Estética Dentária , Anodontia
13.
Braz Oral Res ; 29: 1-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25466326

RESUMO

This study aimed to guide the planning of anticurvature filing using pre-determined anatomical points on teeth to establish directions for proper implementation of the technique. Two hundred digital periapical radiographs of human molar teeth were selected and divided into two groups (n = 100): MX (maxillary) and MD (mandibular) molars. Mesiobuccal roots were considered for the MX group and mesial roots for the MD group. Pre-determined anatomical points required for planning the anticurvature filing on the root canal path were located, and the distances between these points obtained. The anticurvature filing was simulated in two different protocols for each group, and the region of dentin removal and the remaining dentin thickness were measured in the safety and danger zones of the root canals. Statistical analysis was carried out at a significance level of 5%. The distances between the anatomical points and the thickness of remaining dentin showed significant differences when the two groups were compared (p < 0.001). No significant differences were found between the two experimental groups regarding the area of dentin removal at the root region, but differences were detected in comparison with dentin removal at the crown (p < 0.001). In terms of wear produced after simulation of both anticurvature filing protocols, significant differences were verified for all regions, except for the dentin remaining at the danger zone. The radiographic location of anatomical points allows for planning and implementation of controlled and efficient anticurvature filing and can be performed in the same manner for maxillary and mandibular molars.


Assuntos
Arquivamento , Dente Molar/anatomia & histologia , Dente Molar/diagnóstico por imagem , Preparo de Canal Radicular/métodos , Raiz Dentária/anatomia & histologia , Raiz Dentária/diagnóstico por imagem , Análise de Variância , Pontos de Referência Anatômicos/diagnóstico por imagem , Dentina/anatomia & histologia , Dentina/diagnóstico por imagem , Humanos , Odontometria/métodos , Radiografia , Valores de Referência , Reprodutibilidade dos Testes , Estatísticas não Paramétricas
14.
Braz. oral res. (Online) ; 29(1): 1-9, 2015. tab, ilus
Artigo em Inglês | LILACS | ID: lil-777169

RESUMO

This study aimed to guide the planning of anticurvature filing using pre-determined anatomical points on teeth to establish directions for proper implementation of the technique. Two hundred digital periapical radiographs of human molar teeth were selected and divided into two groups (n = 100): MX (maxillary) and MD (mandibular) molars. Mesiobuccal roots were considered for the MX group and mesial roots for the MD group. Pre-determined anatomical points required for planning the anticurvature filing on the root canal path were located, and the distances between these points obtained. The anticurvature filing was simulated in two different protocols for each group, and the region of dentin removal and the remaining dentin thickness were measured in the safety and danger zones of the root canals. Statistical analysis was carried out at a significance level of 5%. The distances between the anatomical points and the thickness of remaining dentin showed significant differences when the two groups were compared (p < 0.001). No significant differences were found between the two experimental groups regarding the area of dentin removal at the root region, but differences were detected in comparison with dentin removal at the crown (p < 0.001). In terms of wear produced after simulation of both anticurvature filing protocols, significant differences were verified for all regions, except for the dentin remaining at the danger zone. The radiographic location of anatomical points allows for planning and implementation of controlled and efficient anticurvature filing and can be performed in the same manner for maxillary and mandibular molars.


Assuntos
Humanos , Arquivamento , Dente Molar/anatomia & histologia , Dente Molar , Preparo de Canal Radicular/métodos , Raiz Dentária/anatomia & histologia , Raiz Dentária , Análise de Variância , Pontos de Referência Anatômicos , Dentina/anatomia & histologia , Dentina , Odontometria/métodos , Valores de Referência , Reprodutibilidade dos Testes , Estatísticas não Paramétricas
15.
Braz. oral res. (Online) ; 29(1): 1-6, 2015. tab, ilus
Artigo em Inglês | LILACS | ID: lil-777259

RESUMO

The aim of this study was to evaluate the influence of the flexion angle of files on the decentralization of root canals during instrumentation. Fifteen lower incisors were instrumented with Protaper Universal files and radiographed in two directions (mesiodistal and buccolingual) before and after instrumentation with a #15 K-file in position for evaluating the flexion angle of files. The specimens were also scanned before and after instrumentation using micro-computed tomography to obtain the canal area and the distance from the center position of the file to the canal walls. Sections located 1.0 mm (end of the canal), 3.0 mm (apical third), 9.0 mm (middle third), and 15.0 mm (cervical third) from the apex were verified. After instrumentation, the flexion angles of files decreased by an average of 0.76º in the buccolingual direction and 1.92º in the mesiodistal direction (p < 0.001); the canal area increased by an average of 0.58, 0.37, 0.23 and 0.13 mm2 from the cervical to the end of the root canal (p < 0.001). Non-instrumented areas were observed on the buccal and lingual walls, and effective action of files was determined on the mesial and distal walls. The sections from the end of the canal showed canal deviation toward the lingual wall, whereas the other sections showed deviation toward the buccal wall. The flexion angles of files influence the final shape of the root canal, resulting in file decentralization along the pathway of the canal.


Assuntos
Humanos , Cavidade Pulpar/anatomia & histologia , Preparo de Canal Radicular/instrumentação , Anatomia Transversal , Instrumentos Odontológicos , Cavidade Pulpar , Incisivo/anatomia & histologia , Incisivo , Odontometria , Valores de Referência , Estatísticas não Paramétricas , Microtomografia por Raio-X
16.
J Endod ; 40(11): 1874-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25227215

RESUMO

INTRODUCTION: The aim of this study was to evaluate the influence of a ferrule, post system, and length on the stress distribution of weakened root-filled teeth. METHODS: The investigation was conducted by using 3-dimensional (3D) finite element analysis. A sound tooth and 8 3D models of a weakened root-filled central incisor were generated using computer-aided design/computer-aided manufacturing software. The models were created without a ferrule and with a 2.0-mm ferrule, restored with a relined glass fiber post or a cast post and core (Cpc), and 12.0- and 7.0-mm post lengths. Each 3D model was imported using ∗.STEP files to the finite element software for mesh generation. The models were subjected to 100-N oblique loading at the palatal surface, and the results were evaluated by von Mises criterion and maximum principal stress distribution. RESULTS: Finite element analysis showed that the Cpc models showed elevated stress levels in the root canal regardless of the presence of a ferrule. Relined glass fiber post models showed homogeneous stress distribution to the dentin external surface similar to the sound tooth model. Without a ferrule, Cpc with a 7- or 12-mm length promoted high levels of tensile stress inside the root canal. CONCLUSIONS: Ferrule presence promoted more satisfactory stress distribution to the roots. Post length influenced the stress distribution only for the models restored with a cast post and core. High levels of tensile stress inside the root canals were verified with a cast post and core, which should be avoided to rehabilitate weakened roots, mainly in the absence of a ferrule.


Assuntos
Planejamento de Prótese Dentária , Análise de Elementos Finitos , Técnica para Retentor Intrarradicular , Preparo Prostodôntico do Dente/métodos , Dente não Vital/patologia , Silicatos de Alumínio/química , Ligas de Cromo/química , Resinas Compostas/química , Projeto Auxiliado por Computador , Materiais Dentários/química , Porcelana Dentária/química , Cavidade Pulpar/patologia , Dentina/patologia , Vidro/química , Humanos , Imagem Tridimensional/métodos , Teste de Materiais , Técnica para Retentor Intrarradicular/instrumentação , Compostos de Potássio/química , Estresse Mecânico
17.
Braz Dent J ; 25(3): 232-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25252259

RESUMO

The aim of this study was to evaluate the root canal anatomy of mandibular incisors before and after endodontic instrumentation, identifying regions inaccessible to the action of files (Critical instrumentation Area - CA) in a three-dimensional perspective. Thirty human mandibular central incisors were selected, assigned to two groups (n=15) and instrumented using ProTaper Universal rotary files. In the RX group, longitudinal digital radiographic images were obtained in the buccolingual (BL) and mesiodistal (MD) views. In the CT group, cross-sectional micro-computed tomography (µCT) images were obtained at 3, 9 and 15 mm from the apex. The canal area of the specimens was evaluated before and after instrumentation using digital images from each group. Data were analyzed using t-test, one-way ANOVA with subdivided parcels and Tukey's test (α=0.05). The canal area found in the MD radiographs was larger than in the BL radiographs, which was also confirmed in the transversal images (p<0.01). The CA was only detected in the MD radiographs and µCT scans. On the root canal configuration, a continuous reduction in the canal conicity was observed in BL radiographs, while in MD view there was a constriction at the cervical third and subsequent increase at the middle third (p<0.01). The conical shape of the root canal was observed only in the BL view. The canal enlargement in BL radiographs was not indicative of homogeneous instrumentation, since unprepared areas (CA) were also verified on the buccal and lingual walls in different images.


Assuntos
Instrumentos Odontológicos , Cavidade Pulpar/anatomia & histologia , Preparo de Canal Radicular , Humanos , Incisivo
18.
Braz. dent. j ; 25(3): 232-236, 07/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-722149

RESUMO

The aim of this study was to evaluate the root canal anatomy of mandibular incisors before and after endodontic instrumentation, identifying regions inaccessible to the action of files (Critical instrumentation Area - CA) in a three-dimensional perspective. Thirty human mandibular central incisors were selected, assigned to two groups (n=15) and instrumented using ProTaper Universal rotary files. In the RX group, longitudinal digital radiographic images were obtained in the buccolingual (BL) and mesiodistal (MD) views. In the CT group, cross-sectional micro-computed tomography (µCT) images were obtained at 3, 9 and 15 mm from the apex. The canal area of the specimens was evaluated before and after instrumentation using digital images from each group. Data were analyzed using t-test, one-way ANOVA with subdivided parcels and Tukey's test (α=0.05). The canal area found in the MD radiographs was larger than in the BL radiographs, which was also confirmed in the transversal images (p<0.01). The CA was only detected in the MD radiographs and µCT scans. On the root canal configuration, a continuous reduction in the canal conicity was observed in BL radiographs, while in MD view there was a constriction at the cervical third and subsequent increase at the middle third (p<0.01). The conical shape of the root canal was observed only in the BL view. The canal enlargement in BL radiographs was not indicative of homogeneous instrumentation, since unprepared areas (CA) were also verified on the buccal and lingual walls in different images.


Este estudo avaliou a anatomia do canal radicular de incisivos inferiores, antes e após a instrumentação endodôntica, identificando regiões inacessíveis à ação das limas (Área Crítica de instrumentação - AC), em uma perspectiva tridimensional. Trinta incisivos centrais inferiores humanos foram selecionados, divididos em dois grupos (n=15), e instrumentados usando limas rotatórias ProTaper Universal. No grupo RX, imagens longitudinais foram obtidas em duas incidências, vestíbulo-lingual (VL) e mésio-distal (MD), por meio de radiografias digitais. No grupo CT, imagens transversais foram obtidas por meio de microtomografia computadorizada (μTC), em secções localizadas a 3 mm, 9 mm, e 15 mm do ápice. A área do canal das amostras foi avaliada antes e após a instrumentação usando as imagens digitais de cada grupo. Os dados foram analisados por meio do teste t, ANOVA a um critério com parcela subdividida e ao teste de Tukey (α=0,05). A área de canal encontrada nas radiografias MD foi maior do que nas radiografias VL, o que também foi confirmado nas imagens transversais (p<0,01). A Área Crítica de instrumentação só foi detectada nas radiografias MD e nas seções de μTC. Na configuração de canal, a redução contínua na conicidade do canal foi observada nas radiografias VL, enquanto na incidência MD, houve uma constrição no terço cervical e um subsequente aumento no terço médio (p<0,01). A forma cônica do canal radicular foi observada somente na visão VL. O alargamento do canal verificado nas radiografias VL não foi indicativo de instrumentação homogênea, uma vez que áreas não instrumentadas (AC) foram observadas nas paredes vestibular e lingual em visões distintas.


Assuntos
Humanos , Instrumentos Odontológicos , Cavidade Pulpar/anatomia & histologia , Preparo de Canal Radicular , Incisivo
19.
Biosci. j. (Online) ; 30(3): 914-924, may/june 2014. graf
Artigo em Inglês | LILACS | ID: biblio-947482

RESUMO

The surface treatment of fiber posts influence the bonding between composite resin cements and intraradicular retainers, being relevant to the prognostic of teeth without coronal structure. This study aimed to evaluate the different fiber post surface treatment protocols described on literature. The search strategy included a review of PubMed/MEDLINE database using fiber post associated with adhesion; bonding; surface treatment; as keywords. Papers not comprehending English language; assessment of post surface treatment; or testing of materials and their physicmechanical properties were excluded. Studies about glass and quartz fiber post surface treatment were considered for this literature review. Among the 190 articles included, silane agent was the material most used (60.52%) for the surface treatment of fiber posts, followed by application of alcoholic solutions (38.29%), and primer and/or adhesive systems (36.84%). Sandblasting of post surface was mentioned in (17.89%), but it affected the physical and mechanical properties. Hydrogen peroxide was mentioned only in 5.78% and it was shown to result on adequate exposure of the glass fibers without damaging them. It was concluded that a consensus for fiber post surface treatment still not exist in the current literature. Among the protocols described, the one using hydrogen peroxide followed by application of silane seems the most promising, since it allows increased bond strengths without fiber damage.


O processo de tratamento da superfície de pinos pré-fabricados de fibra influencia na união entre cimentos resinosos e esses retentores intra-radiculares, sendo relevante para o prognóstico do tratamento restaurador de dentes sem remanescente coronário. Este estudo objetivou avaliar diferentes protocolos de tratamentos de superfície para pinos de fibra descritos na literatura. Como metodologia, realizou levantamento bibliográfico na plataforma PubMed/MEDLINE, com a palavras-chave fiber post associada à adhesion; bonding; surface treatment. Excluíram-se artigos não redigidos em inglês; que não trataram a superfície do pino; e testes de propriedades físicas-mecânicas. Estudos que trataram a superfície de pinos de fibra de quartzo ou vidro foram incluídos. Dentre os 190 artigos incluídos nesta revisão, o agente silano foi o material mais utilizado (60.52%) para tratamento de superfície de pinos de fibra, seguido pela aplicação de álcool (38.29%), e sistema adesivo (36.84%). O jateamento do pino foi mencionado em 17.89%, mas esta técnica resultou em alteração das propriedades físicas e mecânicas. O peróxido de hidrogênio foi mencionado em 5.78% dos manuscritos, entretanto este tratamento permite a adequada exposição das fibras sem danificá-las. Concluiu-se que não consta na literatura protocolo padrão do tratamento da superfície de pinos de fibra. Dentre os protocolos descritos, o protocolo utilizando peróxido de hidrogênio seguido da aplicação do silano aparece como o mais promissor, pois permite resistência de união aumentada sem promover danos as fibras.


Assuntos
Técnica para Retentor Intrarradicular , Pinos Dentários , Peróxido de Hidrogênio , Assistência Odontológica
20.
Full dent. sci ; 5(17): 163-170, jan. 2014. ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-706310

RESUMO

A presença de diastema entre os dentes anteriores pode gerar desarmonia do sorriso e comprometer a estética do paciente. Com a evolução dos materiais e das técnicas restauradoras, o fechamento de diastema empregando resinas compostas tornou-se alternativa viável para resolução da maioria dos casos clínicos. Este tratamento permite restabelecer a função, possibilitando os contatos interproximais, bem como restabelecimento da estética, proporcionando um sorriso mais harmônico e agradável. Este artigo tem como objetivo relatar um caso clínico de correção de diastemas nos dentes anteriores superiores, utilizando resina composta nanoparticulada pela técnica direta para restabelecimento funcional e estético. O caso foi acompanhado por quatro anos, sendo realizados alguns reparos ao longo desse tempo, demonstrando que o fechamento de diastema com resina composta ‚ uma técnica viável e confiável, além de apresentar boa longevidade


The presence of anterior diastema can result on smile disharmony and compromise the patient’s aesthetic. The evolution of dental materials and techniques has made the use of composite resin for diastema closure a viable option treatment for most clinical cases. It restores function allowing the interproximal contacts, as well as harmony, reestablishing of the smile’s aesthetic. This clinical report aims at demonstrating the clinical correction of an anterior diastema restoring the functional anatomy and especially aesthetic through nanofilled composite resin restorations. The case was followed for 4-years and some repairs were carried out over this time, demonstrating the reliability and viability of the technique, with good longevity of the treatment


Assuntos
Humanos , Masculino , Adulto Jovem , Diastema , Facetas Dentárias/efeitos adversos , Satisfação do Paciente , Planejamento de Dentadura/métodos , Resinas Compostas/farmacocinética , Sorriso/psicologia
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