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Anterior tooth fracture after endodontic treatment is a real and multifactorial possibility because of root weakening due to tooth structure remnant loss and existing oblique occlusal forces. The fracture influenceson esthetics and causes masticatory dysfunction. Preventively, one of the treatments widely accepted is the use of intracanal posts made of metal, carbon fiber, fiberglass and ceramics. The metal and carbon fiber posts are very efficient but do not favor esthetics, while the fiberglass and ceramics posts are both durable and aesthetics. The reinforcement with these biomaterials is advantageous and leads to a favorable prognosis. This study showed a case in which intracanal reinforcement could have prevented the fracture of a devitalized maxillary anterior tooth and provided a brief discussion about the available options for this type of rehabilitation. The use of glass fiber reinforcement posts fordevitalized tooth structure is indicated to prevent dental fractures. Ceramic posts have been indicated in cases with insufficient coronal remaining to support thecore material.

A fratura de dentes anteriores após tratamento endodôntico é uma possibilidade real e multifatorial. Isso se deve ao enfraquecimento da raiz devido à perda do remanescente dental somado às forças oclusais oblíquas existentes. Esta fratura influencia a estética do paciente além de causar disfunção mastigatória. Na prevenção, um dos tratamentos utilizados e muito bem aceitos, é o uso de pinos intra-radiculares. Estes podem ser confeccionados em metais, fibra de carbono, fibra de vidro e em cerâmica. Os pinos de metal e de fibra de carbono são muito eficientes, porém não favorecem a estética, enquanto que os pinos de fibra de vidro e os de cerâmica são resistentes e favorecerem a estética. O reforço com esses biomateriais é vantajosos e leva a um prognóstico favorável. O presente estudo apresenta um caso clínico onde o reforço intracanal poderia ter prevenido a fratura de um dente ântero-superior desvitalizado e realiza uma breve discussão acerca das opções disponíveis para este tipo de reabilitação. O uso de pinos de fibra de vidro como reforço da estrutura de dentes desvitalizados é indicado na prevenção de fraturas dentárias, porém núcleos cerâmicos fundidos são indicados para remanescentes coronários insuficientes para suportar o material de preenchimento.

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The aim of this study was to evaluate the effects of different light-curing units and resin cement curing types on the bond durability of a feldspathic ceramic bonded to dentin. The crowns of 40 human molars were sectioned, exposing the dentin. Forty ceramic blocks of VITA VM7 were produced according to the manufacturer's recommendations. The ceramic surface was etched with 10% hydrofluoric acid / 60s and silanized. The dentin was treated with 37% phosphoric acid / 15s, and the adhesive was applied. The ceramic blocks were divided and cemented to dentin according to resin cement / RC curing type (dual- and photo-cured), light-curing unit (halogen light / QTH and LED), and storage conditions (dry and storage / 150 days + 12,000 cycles / thermocycling). All blocks were stored in distilled water (37°C / 24h) and sectioned (n = 10): G1 - QTH + RC Photo, G2 - QTH + RC Dual, G3 - LED + RC Photo, G4 - LED + RC Dual. Groups G5, G6, G7, and G8 were obtained exactly as G1 through G4, respectively, and then stored and thermocycled. Microtensile bond strength tests were performed (EMIC), and data were statistically analyzed by ANOVA and Tukey's test (5%). The bond strength values (MPa) were: G1 - 12.95 (6.40)ab; G2 - 12.02 (4.59)ab; G3 - 13.09 (5.62)ab; G4 - 15.96 (6.32)a; G5 - 6.22 (5.90)c; G6 - 9.48 (5.99)bc; G7 - 12.78 (11.30)ab; and G8 - 8.34 (5.98)bc. The same superscript letters indicate no significant differences. Different light-curing units affected the bond strength between ceramic cemented to dentin when the photo-cured cement was used, and only after aging (LED > QTH). There was no difference between the effects of dual- and photo-cured resin-luting agents on the microtensile bond strength of the cement used in this study.

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The aim of this study was to evaluate the effects of different light-curing units and resin cement curing types on the bond durability of a feldspathic ceramic bonded to dentin. The crowns of 40 human molars were sectioned, exposing the dentin. Forty ceramic blocks of VITA VM7 were produced according to the manufacturer's recommendations. The ceramic surface was etched with 10% hydrofluoric acid / 60s and silanized. The dentin was treated with 37% phosphoric acid / 15s, and the adhesive was applied. The ceramic blocks were divided and cemented to dentin according to resin cement / RC curing type (dual- and photo-cured), light-curing unit (halogen light / QTH and LED), and storage conditions (dry and storage / 150 days + 12,000 cycles / thermocycling). All blocks were stored in distilled water (37°C / 24h) and sectioned (n = 10): G1 - QTH + RC Photo, G2 - QTH + RC Dual, G3 - LED + RC Photo, G4 - LED + RC Dual. Groups G5, G6, G7, and G8 were obtained exactly as G1 through G4, respectively, and then stored and thermocycled. Microtensile bond strength tests were performed (EMIC), and data were statistically analyzed by ANOVA and Tukey's test (5%). The bond strength values (MPa) were: G1 - 12.95 (6.40)ab; G2 - 12.02 (4.59)ab; G3 - 13.09 (5.62)ab; G4 - 15.96 (6.32)a; G5 - 6.22 (5.90)c; G6 - 9.48 (5.99)bc; G7 - 12.78 (11.30)ab; and G8 - 8.34 (5.98)bc. The same superscript letters indicate no significant differences. Different light-curing units affected the bond strength between ceramic cemented to dentin when the photo-cured cement was used, and only after aging (LED > QTH). There was no difference between the effects of dual- and photo-cured resin-luting agents on the microtensile bond strength of the cement used in this study.

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Considerando que a guta percha pode entrar em contato com os tecidos apicais e periapicais no momento da obturação, os cones devem ser desinfectados antes do uso para que não sirvam de veículo para microrganismos patogênicos. Objetivo: A proposta deste estudo foi avaliar o efeito do NaOCl a 1% e a 2,5% sobre a morfologia superficial dos cones de guta-percha em função do tempo de imersão e analisar o selamento marginal de canais obturados com estes cones. Métodos: Para isto, foi analisada pelo MEV a morfologia superficial de 110 cones de guta-percha principal, divididos em 3 grupos: G1 (controle), G2 e G3 imersos no NaOCl 1% e 2,5% durante 30 min, 6, 12 e 24 h. Para análise do selamento foram utilizados 72 dentes unirradiculados humanos com o comprimento das raízes padronizados entre 16-18 mm, que foram divididas em 6 grupos, instrumentadas e obturadas com o cimento endodôntico AH Plus e com os cones imersos nas soluções de NaOCl 1% e 2,5% durante 30 min e 24 h (grupos A, B, C e D); os tempos convencionais foram utilizados como controles (E e F). As raízes foram impermeabilizadas externamente, exceto no forame apical, imersas no corante tinta da Índia por mais de 24 h e diafanizadas. A leitura das microinfiltrações foi realizada pelo esteromicroscópio, as imagens obtidas eram fotografadas e salvas no computador para medir as microinfiltrações utilizando o programa Image Tool. Resultado: Os resultados mostraram alteração gradativa crescente na morfologia superficial dos cones de acordo com o aumento da concentração do NaOCl e do tempo de imersão. As médias de microinfiltração obtidas em mm foram de: A = 1,17; B = 1,26; C = 1,44; D =1,60; E = 1,14 e F = 1,22. Através do Teste Dunnett e da análise de variância (ANOVA) não houve diferença estatisticamente significante...

Considering that gutta-percha may contact the apical and periapical tissues during root canal filling, they must be disinfected to avoid the propagation of pathogenic microorganisms. Objective: The purpose of this study was to evaluate the effect of 1% and 2.5% sodium hypochlorite on the surface morphology of gutta-percha points according to the period of immersion, and to analyze the marginal sealing of root canal filling with these points. Methods: The surface morphology of 110 gutta-percha points was analyzed by scanning electron microscopy, divided into 3 groups: G1 (control), G2 and G3, respectively immersed in 1% and 2.5% sodium hypochlorite, for 30 min, 6 h, 12 h and 24 h. Analysis of marginal sealing was performed on 72 single-rooted human teeth with root length of 16-18 mm, divided into 6 groups, prepared and filled with AH Plus sealer with the points immerged in the solution, the convencional times were taken control (A and B) and during 30 min and 24 h (groups C, D, E and F). The roots received an impermeable coating on the external surface, except for the apical foramen; the roots were then immersed in India ink for 24 h and were made transparent. Results: The results showed increasing and progressive alteration in the surface morphology of points according to the increase in the solution concentration and period of immersion. The microleakage means obtained in mm were: A = 1.14; B = 1.22; C = 1.17; D = 1.26; E = 1.44 and F = 1.60. The Dunnett test and analysis of variance were application. Conclusion: It was concluded that the increase in sodium hypochlorite concentration and period of immersion of points in the solution promote gradual increasing alteration in the surface morphology of points; microleakage means of these obturations did not reveal statistically significant differences.

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Objective: This study evaluated the morphological alterations, through scanning electronic microscopy (SEM), which occur in the gutta-percha points exposed to periods longer than those recommended. Material and method: 2% chlorhexidine (CLX), 2.5% sodium hypochlorite (NaOCL), 2% peracetic acid (PA) and 0.25% peracetic acid solution (PAS) were the solutions used for the following periods: 1 min, 30 min, 6 h and 12 h. The groups were divided according to the solution and disinfection period (n=12). Results: The results indicated that there was statistically significant differences among the solutions and period tested. At 1 min, all solutions did not differ from the control group. After 30 min, PAS significantly altered the morphology of the points. The energy dispersive spectrometry (EDS) test indicated that all substances and periods altered the chemical composition of the gutta-percha points. At 12 h, the effect of disinfection on the obturation leakage was also evaluated Accordingly, PAS showed statistically significant differences in relation to control group, because 100% of the roots exhibited leakage. The other groups (CLX, NaOCL and PA), although without statistical differences, showed 9, 8 and 8 out of 12 roots with leakage, respectively. Conclusion: It can be concluded that the disinfection process can cause morphological alterations whether the immersion period was exceeded. Also, these solutions can influence on the obturation sealing.

Objetivo: Essa pesquisa avaliou as alterações morfológicas, em microscopia eletrônica de varredura (MEV), que ocorrem na superfície dos cones de guta-percha em períodos excedidos aos preconizados. Material e método: Clorexidina 2% (CLX), hipoclorito de sódio 2,5% (NaOCL), ácido peracético 2% (AP) e solução de ácido peracético 0,25% (SAP) foram as soluções utilizadas nos períodos de 1 min, 30 min, 6 h e 12 h. Os grupos foram divididos de acordo com a solução e período de desinfecção (n=12). Resultados: Os resultados indicaram que houve diferença estatística significante entre as soluções e períodos testados. Em 1 min, todas as soluções não diferiram do controle. Após 30 min, a SAP alterou significativamente a morfologia dos cones. O teste de espectrometria de energia dispersiva (EDS) indicou que todas as substâncias e períodos alteram a composição química dos cones de guta-percha. A relação da desinfecção na microinfiltração da obturação também foi avaliada nos grupos que sofreram desinfecção por 12 h. O grupo da SAP apresentou diferença estatística significante em relação ao controle, pois 100% das suas raízes apresentaram infiltração. Os demais grupos da CLX, NaOCL e AP, embora sem diferença estatística significante, tiveram respectivamente 9, 8 e 8 do total de 12 das suas raízes com infiltração. Conclusão: Conclui-se que o processo de desinfecção pode causar alterações morfológicas se o período de imersão for excedido e que, além de alterarem a composição química dos cones de guta-percha, estas soluções podem influenciar no selamento da obturação

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Objective: To evaluate the apical leakage exhibited by root canals filled with gutta-percha points and three different endodontic sealers. Material and Methods: Thirty-five human molars were used and had their palatal (maxillary molars) and distal roots (mandibular molars) sectioned, standardized and instrumented with Mtwo rotary system. The roots were filled through active lateral condensation technique and divided into three groups (n=10), according to the endodontic sealer employed: G1- AH Plus, G2- Fill Canal, G3- MTA Fillapex. All groups were filled by gutta-percha points and endodontic sealer. Gutta-percha points were immersed into sodium hypochlorite for 24 h to achieve disinfection. After the filling procedure, the roots were immersed into Indian ink for posterior diaphanization and obtainment of the images through stereomicroscopy. By analyzing the images in Adobe Illustrator CS5 software, the level of apical leakage was determined. The data obtained were submitted to Kruskal Wallis and Dunn tests, with level of significance set at 5%. Results: Statistically significant differences were found between G1 and G3. G2 did not show statistically significant differences. G1 exhibited the smallest apical leakage mean (12.85), followed by G2 (109.84) and G3 (101.15). Conclusions: Root canal obturation with gutta-percha points and AH plus sealer through lateral condensation technique provided lower apical leakage rates than the other endodontic sealers evaluated

Objetivo: Avaliar a infiltração apical apresentada em canais radiculares obturados com guta-percha e três diferentes cimentos obturadores. Material e Métodos: Foram utilizados 35 molares humanos, os quais tiveram suas raízes linguais (molares superiores) e distais (molares inferiores) seccionadas, padronizadas e instrumentadas com o sistema rotatório Mtwo. As raízes foram obturadas através da técnica de condensação lateral ativa e divididas em 3 grupos (n=10), de acordo com o cimento obturador utilizado: G1- AH Plus, G2- Fill Canal, G3- MTA Fillapex. Todos os grupos foram obturados com o conjunto guta-percha e cimento obturador, sendo que a guta-percha utilizada permaneceu 24 h imersa em hipoclorito de sódio, para sua desinfecção. Após a obturação, as raízes foram imersas em corante tinta da Índia, para posterior diafanização e obtenção de imagens através de estereomicroscópio. Através da análise das imagens no programa Adobe Illustrator CS5 foi determinado o nível de infiltração apical. Os dados obtidos foram submetidos aos testes estatísticos de Kruskal Wallis e Dunn, com nível de significância 5%. Resultados: Verificou-se presença de diferença estatística significante entre o G1 e G3, sendo que G2 não diferiu estatisticamente dos demais grupos. O G1 apresentou a menor média de infiltração apical (12.85), seguida pelo G2 (109.84) e G3 (101.15). Conclusões: A obturação de canais radiculares com cones de guta-percha e cimento AH plus através da técnica de condensação lateral proporciona baixos índices de infiltração apical, quando comparada aos demais cimentos obturadores avaliados

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Avaliar, com o auxílio de tomografias computadorizadas, a disponibilidade óssea para a realização de cirurgias de instalação de implantes osseointegrados em função da localização do canal mandibular.Metodologia: trinta e duas tomografias computadorizadas de mandíbulas edêntulas foram analisadas na região do primeiro molar inferior. As mensurações desconsideraram a crista do rebordo residual até que se alcançasse uma espessura óssea mínima de 5,0mm, e, a partir desse ponto foi mensurada a distância existente até o teto superior do canal mandibular.Resultados: observou-se, em média, 11,625mm de tecido ósseo, variando de 8,0 a 16,2mm, entre o teto superior do canal mandibular e a porção do rebordo alveolar residual, com espessura mínima de 5,0mm para a instalação do implante.Conclusão: na maioria dos casos avaliados, existiu osso suficiente em altura e espessura para uma adequada instalação de implantes osseointegrados...

Determine, by means of computerized tomography, the bone availability for implantation in the edentate region of the lower first molar, regarding the localization of the mandibular canal.Methodology: thirty-two computerized tomographies of edentate jaws in the region of the lower first molar were evaluated. For the measurements, the crest of the residual alveolar process was discarded, until a width of 5.0mm was reached. From there, the distance until the roof of the mandibular canal was measured.Results: there was an average of 11.625mm of the bone tissue, ranging from 8.0 a 16.2mm between the roof of the mandibular canal and the residual alveolar process, with a minimum thickness of 5.0mm for the implant installation.Conclusion: in the majority of the cases there was enough bone in height and width for osseointegrated implants...

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The aim of this study was to evaluate the effectiveness of 2% peracetic acid for the disinfection of gutta-percha cones contaminated in vitro with Escherichia coli, Staphylococcus aureus, Streptococcus mutans, Candida albicans and Bacillus subtilus (in spore form). Two hundred and twenty-five gutta-percha cones were contaminated with standardized suspensions of each microorganism and incubated at 37°C for 24 h. The cones were divided into 10 experimental groups (n = 15), according to the microorganism tested and disinfection testing times. The disinfection procedure consisted of immersing each cone in a plastic tube containing the substance. The specimens remained in contact with the substance for 1 or 2.5 minutes. Afterwards, each cone was transferred to a 10% sodium thiosulphate solution (Na(2)S(2)O(3)) to neutralize the disinfectant. Microbial biofilms adhering to the cones were dispersed by agitation. Aliquots of 0.1 ml of the suspensions obtained were plated on Sabouraud dextrose agar, or brain and heart infusion agar, and incubated at 37°C for 24 h. The results were expressed in colony forming units (CFU/ml) and the data were submitted to the Wilcoxon Signed Rank Test (level of significance at 0.05). A significant reduction was observed, after 1 minute of exposure, in the test solution for C. albicans (p = 0.0190), S. aureus (p = 0.0001), S. mutans (p = 0.0001), B. subtilis (p = 0.0001), and E. coli (p = 0.0001). After 2.5 minutes of exposure, 100% of the microbial inocula were eliminated. It was concluded that the 2% peracetic acid solution was effective against the biofilms of the tested microorganisms on gutta-percha cones at 1 minute of exposure.

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The aim of this study was to evaluate the effectiveness of 2 percent peracetic acid for the disinfection of gutta-percha cones contaminated in vitro with Escherichia coli, Staphylococcus aureus, Streptococcus mutans, Candida albicans and Bacillus subtilus (in spore form). Two hundred and twenty-five gutta-percha cones were contaminated with standardized suspensions of each microorganism and incubated at 37°C for 24 h. The cones were divided into 10 experimental groups (n = 15), according to the microorganism tested and disinfection testing times. The disinfection procedure consisted of immersing each cone in a plastic tube containing the substance. The specimens remained in contact with the substance for 1 or 2.5 minutes. Afterwards, each cone was transferred to a 10 percent sodium thiosulphate solution (Na2S2O3) to neutralize the disinfectant. Microbial biofilms adhering to the cones were dispersed by agitation. Aliquots of 0.1 ml of the suspensions obtained were plated on Sabouraud dextrose agar, or brain and heart infusion agar, and incubated at 37°C for 24 h. The results were expressed in colony forming units (CFU/ml) and the data were submitted to the Wilcoxon Signed Rank Test (level of significance at 0.05). A significant reduction was observed, after 1 minute of exposure, in the test solution for C. albicans (p = 0.0190), S. aureus (p = 0.0001), S. mutans (p = 0.0001), B. subtilis (p = 0.0001), and E. coli (p = 0.0001). After 2.5 minutes of exposure, 100 percent of the microbial inocula were eliminated. It was concluded that the 2 percent peracetic acid solution was effective against the biofilms of the tested microorganisms on gutta-percha cones at 1 minute of exposure.

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O uso de radiografias digitais para a realização da odontometria tem ganhado espaço na endodontia, pois possui vantagens como menor tempo de exposição à radiação, manipulação e melhor visualização da imagem pelos softwares, armazenamento em computador, eliminação da película radiográfica e dos líquidos processadores. O objetivo deste estudo foi analisar a confiabilidade da odontometria realizada por diferentes métodos radiográficos digitais comparados à radiografia convencional. Para radiografia digital, foram utilizados os aparelhos RVG Trophy 2000 (Trophy Radiologie, Vincennes - França) e DSX600 (OWANDY Dental Imaging Systems & Software), analisados pelo software Quickvision (Mitutoyo, USA). Neste estudo, foram empregados 50 dentes incisivos inferiores com abertura coronária, da disciplina de Endodontia da Faculdade de Odontologia de São José dos Campos, UNESP. O comprimento dos dentes foi aferido com um paquímetro eletrônico (CD-15CX, Mitutoyo - Japão) e o comprimento do canal radicular com limas endodônticas, medidas tidas como controle. O comprimento de trabalho foi estabelecido com a lima 2mm aquém do ápice radicular. Os dentes com as limas no comprimento de trabalho foram radiografados para posteriormente serem medidos o comprimento do dente e o comprimento de recuo. Por meio dos testes estatísticos ANOVA (5%) e Tukey, foi possível verificar diferenças estatísticas nas medidas do recuo apical quando comparado o controle com o RVG; os demais não demonstraram diferenças significantes entre si. Pode-se concluir que os métodos radiográficos digitais utilizados, apesar de apresentarem diferenças estatísticas, são considerados bons recursos de diagnóstico para a realização de odontometria, podendo ser utilizados com segurança

The use of digital radiographs by odontometrics has been gaining ground in odontology because of its many advantages such as: shorter time of radiation exposure, manipulation and better image visualization by software, computer storage, no need of radiographic film nor processing liquids. The objective of the research was to analyze the reliability of odontometrics performed by different digital radiographic methods as compared to conventional radiography. RGV Trophy 2000 (Trophy Radiologie, Vincennes, France) and DSX 600 (OWANDY Dental Imaging Systems & Software) equipment were used – and analyzed by Quickvision (Mitutoyo,USA) software. Fifty lower jaw incisor teeth with crown opening (that belonged to the Edodontics Course of the São José dos Campos School of Odontology-UNESP) were used in the research. The length of the tooth was measured with an electronic caliper (CD-15CX, Mitutoyo,Japan) and the length of the root canal with edodontics files. These measures were held for experiment control reference. The “working length” was set with a 2mm file below the root tip or apex. Tooth with limes in the working length were radiographed and after that had their length and their “backing up” measured. By using statistical tests ANOVA(5%) and Tukey, it was possible to check statistical differences in the backing up measures when the control measures were compared with the RVG. The other groups did not show any significant differences among themselves. The conclusion is that the digital radiograph methods, in spite of presenting some statistical differences, may be considered a good help for odontometrics and may be safely used.

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