Restauração semidireta do tipo Endocrown em dente posterior extensamente destruído / Endocrown semidirect restoration for extensevely damaged posterior teeth

Endocrowns são coroas confeccionadas utilizando a câmara pulpar como recurso mecânico de retenção, evitando a necessidade de pinos e preparos mais extensos. Essas restaurações podem ser confeccionadas através de diferentes técnicas, dentre elas, a técnica semidireta. Esta técnica consiste na confecção de restauração extrabucal de resina composta, geralmente em modelos rígidos ou flexíveis, e posterior cimentação, sendo uma alternativa que facilita a reprodução anatômica, acabamento e polimento da restauração e menor custo para o paciente. O objetivo deste trabalho é relatar um caso clínico de paciente com molar extensamente destruído e tratado endodonticamente, em que uma restauração do tipo Endocrown foi confeccionada através de técnica semidireta. Neste caso, o dente 46 de um paciente do gênero masculino, de 33 anos, foi preparado com pontas diamantadas tronco-cônicas, de modo a se obter um preparo ligeiramente expulsivo, este foi moldado com silicona de condensação. Ao molde, foi injetada silicona de adição para obtenção de um modelo flexível para a confecção da restauração. Posteriormente, a restauração foi realizada neste modelo, utilizando-se resina Bulk Fill para preenchimento da cavidade, seguida de dentina A3, aplicação de pigmento ocre e camada de resina de esmalte A2 e, após fotopolimerização, a peça foi cimentada com cimento resinoso. Os procedimentos de acabamento e polimento foram realizados fora da boca e também foi realizado procedimento de pós-polimerização para obtenção de melhores propriedades mecânicas da restauração. A restauração semidireta do tipo Endocrown devolveu função e estética ao molar, com adequada adaptação marginal, garantindo resultados imediatos, baixo custo e conforto ao paciente (AU).

Endocrowns are restorations performed using the pulp chamber for mechanical retention, avoiding more extensive preparations and the need of posts and pins. These restorations can be made through different techniques, among them, the semidirect technique. This technique consists in the preparation of an extraoral restoration of composite resin, usually in rigid or flexible dies followed by cementation, which is an alternative that facilitates the anatomical reproduction, finishing and polishing of the restoration, and lower cost for the patient. The purpose of this paper is to report a clinical case of a patient with extensively destroyed and endodontically treated molars, in which an Endocrown restoration was performed using a semidirect technique. In this case, the tooth 46 of a 33-year-old male patient was prepared with cone-shaped diamond tips in order to obtain a slightly expulsive preparation, the impression was made with condensation silicone, and the flexible die was obtained through addition silicone. Subsequentely, the restoration was performed in this die, using a Bulk Fill resin composite, followed by dentin A3, application of ocher pigment and enamel A2 resin layer and, after photopolymerization, the resin Endocrown was cemented with resin cement. The finishing and polishing procedures were performed outside the mouth and a post-polymerization procedure was also performed to obtain better mechanical properties of the restoration. The semidirect restoration of the Endocrown replaced function and aesthetics to the molar, with adequate marginal adaptation, guaranteeing immediate results, low cost and comfort to the patient (AU).

Influence of light activation of simplified adhesives on the shear bond strength of resin cements to a leucite-reinforced ceramic.

OBJECTIVE: This study aims to evaluate the influence of the light activation of simplified adhesives on the shear bond strength of resin cements to a glass-ceramic. Three factors were evaluated: (1) cement in two levels (light cured and dual cured); (2) adhesive in two levels (Single Bond 2 and Single Bond Universal), and (3) light activation in two levels (yes or no). MATERIALS AND METHODS: Thirty-two 1-mm thick slices of a leucite-reinforced glass-ceramic (IPS Empress CAD) were divided into eight groups according to adhesive (Single Bond 2 or Single Bond Universal), cement (AllCem Veneer or AllCem), and light activation of the adhesive before application of the cement (yes or no). Ceramic surfaces were etched for 60 s with 5% hydrofluoric acid, and adhesives were applied. Four cement cylinders were made over each ceramic slice (n = 16) and then submitted to shear bond strength tests. STATISTICAL ANALYSIS: Data were analyzed with three-way ANOVA and Tukey (α = 0.05). RESULTS: There were significant differences between adhesives (P < 0.0001) and no differences between cements (P = 0.0763) and light activation (P = 0.4385). No interaction effect occurred (P = 0.05). Single Bond 2 showed higher bond strength than Single Bond Universal. CONCLUSIONS: The light activation of the adhesive before the application of the resin cement did not influence the bond strength.

Influence of antimicrobial solutions in the decontamination and adhesion of glass-fiber posts to root canals.

OBJECTIVE: This study evaluated the effect of root canal disinfectants on the elimination of bacteria from the root canals, as well as their effect on glass-fiber posts bond strength. MATERIAL AND METHODS: Fifty-three endodontically treated root canals had post spaces of 11 mm in length prepared and contaminated with E. faecalis. For CFU/ml analysis, eight teeth were contaminated for 1 h or 30 days (n=4). Teeth were decontaminated with 5% NaOCl, 2% CHX, or distilled water. As control, no decontamination was conducted. After decontamination, sterile paper points were used to collect samples, and CFU/ml were counted. For push-out, three groups were evaluated (n=15): irrigation with 2.5% NaOCl, 2% CHX, or sterile distilled water. A bonding agent was applied to root canal dentin, and a glass-fiber post was cemented with a dual-cured cement. After 24 h, 1-mm-thick slices of the middle portion of root canals were obtained and submitted to the push-out evaluation. Three specimens of each group were evaluated in scanning electron microscopy (SEM). Data were analyzed with one-way ANOVA and Dunnett's T3 test (α=0.05). RESULTS: The number of CFU/ml increased from 1 h to 30 days of contamination in control and sterile distilled water groups. Decontamination with NaOCl was effective only when teeth were contaminated for 1 h. CHX was effective at both contamination times. NaOCl did not influence the bond strength (p>0.05). Higher values were observed with CHX (p<0.05). SEM showed formation of resin tags in all groups. CONCLUSION: CHX showed better results for the irrigation of contaminated root canals both in reducing the bacterial contamination and in improving the glass-fiber post bonding.

Influence of antimicrobial solutions in the decontamination and adhesion of glass-fiber posts to root canals

AbstractObjective This study evaluated the effect of root canal disinfectants on the elimination of bacteria from the root canals, as well as their effect on glass-fiber posts bond strength.Material and Methods Fifty-three endodontically treated root canals had post spaces of 11 mm in length prepared and contaminated with E. faecalis. For CFU/ml analysis, eight teeth were contaminated for 1 h or 30 days (n=4). Teeth were decontaminated with 5% NaOCl, 2% CHX, or distilled water. As control, no decontamination was conducted. After decontamination, sterile paper points were used to collect samples, and CFU/ml were counted. For push-out, three groups were evaluated (n=15): irrigation with 2.5% NaOCl, 2% CHX, or sterile distilled water. A bonding agent was applied to root canal dentin, and a glass-fiber post was cemented with a dual-cured cement. After 24 h, 1-mm-thick slices of the middle portion of root canals were obtained and submitted to the push-out evaluation. Three specimens of each group were evaluated in scanning electron microscopy (SEM). Data were analyzed with one-way ANOVA and Dunnett’s T3 test (α=0.05).Results The number of CFU/ml increased from 1 h to 30 days of contamination in control and sterile distilled water groups. Decontamination with NaOCl was effective only when teeth were contaminated for 1 h. CHX was effective at both contamination times. NaOCl did not influence the bond strength (p>0.05). Higher values were observed with CHX (p<0.05). SEM showed formation of resin tags in all groups.Conclusion CHX showed better results for the irrigation of contaminated root canals both in reducing the bacterial contamination and in improving the glass-fiber post bonding.

Adhesion and formation of tags from MTA Fillapex compared with AH Plus® cement

Introduction and Objective: The aim of this study was two-fold: 1) to evaluate, in vitro, the shear bond strength of two sealers by push-out test and 2) to assess the failures after displacement. Additionally, the formation of tags was observed by SEM. Material and methods: Forty mandibular premolars were selected and the canals were subjected to biomechanical preparation with rotary instruments. These specimens were divided into two groups according to the sealer (n = 20): GI - MTA Fillapex and GII - AH Plus. All roots were filled with sealer only, without gutta-percha. After a period corresponding to three times the setting time of the sealer, the roots were sectioned transversely into slices of 1 mm thickness, to obtain one slice from the cervical third, to be used in the push-out test. Following, two slices of each group were randomly chosen for ultrastructural analysis by scanning electron microscopy (SEM). The data obtained in shear bond strength test were subjected to statistical analysis. Results: AH Plus cement exhibited higher shear bond strength values (1.332±0.75 MPa) than MTA Fillapex (0.071±0.07 MPa), with statistically significant differences. Conclusion: MTA Fillapex has a low bond strength with less formation of tags than AH Plus.

Bond strength of fiber-reinforced posts to deproteinized root canal dentin.

AIM: This study evaluated the push-out bond strength of cemented fiber posts after deproteinization of root canal dentin walls with NaOCl. The effect of the application of an antioxidant solution (sodium ascorbate) was also evaluated. MATERIALS AND METHODS: A three-step etch-and-rinse (Scotch-bond - 3M Espe) and a one-step self-etching adhesive (Xeno III - Dentsply Caulk) were evaluated. Thirty bovine incisor roots were divided into 3 groups: a. Irrigation with physiologic solution (control). b. Deproteinization with 10 minutes irrigation of 5% NaOCl. c. Deproteinization with NaOCl followed by 10 minutes irrigation with 10% ascorbic acid. Fiber posts were cemented with a dual-cured cement (Rely X ARC - 3M ESPE). The push-out bond strength was evaluated after 24 hours of storage in distilled water. The data were analyzed with three-way ANOVA, one-way ANOVA and Tukey's test (α = 0.05). RESULTS: There were significant differences between groups (p < 0.05). The bond strength of Scotchbond was not influenced by the deproteinization. Xeno III showed a decrease in bond strength when deproteinized with 5% NaOCl (p < 0.05). For Xeno III, the subsequent irrigation with ascorbic acid was able to reverse the effect of the deproteinization. Considering the radicular thirds, the bond strength varied in the sequence-apical < middle < coronal. CONCLUSION: Only the all-in-one adhesive was influenced by the deproteinization. Considering the respective control groups, both systems showed similar bond strength results. CLINICAL SIGNIFICANCE: The decreased bond strength of the self-etching adhesive following deproteinization seams to be related to the oxidant effect of the NaOCl solution and the subsequent irrigation with ascorbic acid was able to reverse the effect of the deproteinization.

Staining susceptibility of methacrylate and silorane-based materials: influence of resin type and storage time

Introduction: The color stability of composite resins is a fundamental factor in their clinical behavior. Objective: To evaluate the color stability of composite resins of different colors exposed to a cola-based soft drink after different storage periods. Additionally, three methacrylate-based materials and one silorane-based material were evaluated. Material and methods: Specimens of three methacrylate-based materials (Opallis EA3, DA3 and T-Neutral; Filtek Supreme XT A3E, A3D and CT; 4 Seasons A3 Enamel, A3 Dentin and High Value) and one silorane-based material (Filtek P90 A3) were prepared, light-cured for 40 s, and manually polished with Sof-Lex discs. Samples were stored for 1 h, 24 h or 7 days. The color was evaluated by CIE-Lab system before and after immersion for 10 min in a cola-based soft drink. Color variation (ΔE) was calculated from individual values of L*, a* and b*, being considered imperceptible when < 1, clinically acceptable when ≤ 3.3, and clinically inacceptable when higher than 3.3. Data were evaluated by two-way Anova and Dunnett's T3 tests (α = 0.05). Results: There were differences among the resins (p < 0.001), with an interaction effect being also observed (p < 0.001). Storage time was not significant (p = 0.246). P90 showed a ΔE smaller than one unit at all studied times. Supreme XT CT and 4 Seasons High Value showed higher ΔE, but not above the critical value of 3.3. The only material that showed ΔE higher than 3.3 was Opallis DA3 after 1 h of storage. Conclusion: The silorane-based composite resin showed smaller ΔE at the times studied.

Undergraduate students introduction to manual and rotary root canal instrumentation.

The aim of this study was to evaluate the performance of undergraduates in their first contact with manual and rotary root canal instrumentation. Forty-two students who had never worked on a root canal before instrumented 42 extracted lower-incisors. Participants were assigned to one of two groups: Rotary instrumentation or manual instrumentation. Pre- and post-operative computed tomography scans were obtained with a 3-dimensional dental imaging system. Starting and finishing times of preparation were recorded. The cross-sectional area of the root canal was analyzed with 2-mm-below-the-apex initial and final transverse images recorded through a digital imaging system and analyzed with software to measure the initial and final area of the root canal in mm(2). Data from the cross-sectional area of the root canal and time spent were subjected to the Mann-Whitney's U-test (p<0.05). The rotary instrumentation group showed smaller time for preparation (p=0.0204). No differences between rotary and manual instrumentation regarding the cross-sectional area of the root canal were observed (p=0.25). No accidents occurred. Undergraduate students showed good performance in their first contact with the manual and rotary instrumentation with regard to time spent and cross-sectional area of the root canal, with no operative accidents.

Etiologia, diagnóstico e tratamento da reabsorção cervical externa: revisão de literatura / Etiology, diagnosis and treatment of external cervical resorption: literature review

Introdução: a reabsorção cervical externa (RCE) é uma forma progressiva e agressiva de destruição da estrutura dental, caracterizada pela localização cervical e pela presença de tecido fibrovascular preenchendo a região reabsorvida. A RCE não apresenta uma etiologia específica, embora existam alguns fatores predisponentes para que ela ocorra. Devido à ausência de sintomas, a reabsorção cervical externa acaba se tornando um achado radiográfico, sendo detectada em exames de rotina. Algumas vezes, pode ocorrer a comunicação da lesão com o canal radicular e surgirem sintomas relacionados à pulpite. Em outros casos, clinicamente, a RCE pode ser identificada apenas como uma mancha rosa na margem gengival da coroa do dente afetado. Para o correto diagnóstico da RCE, além da técnica radiográfica convencional, é indicada a realização da tomografia computadorizada cone beam para avaliar a exata extensão e localização da lesão. O tratamento dependerá do estágio de evolução da reabsorção e, mesmo com a aplicação de materiais como o MTA, aRCE tem um prognóstico duvidoso na maioria dos casos. Objetivo: rever a literatura sobre a etiologia, diagnóstico e o tratamento da reabsorção cervical externa. Conclusão: a reabsorção cervical externa quanto mais cedo detectada melhor será seu prognóstico. Pacientes que apresentem algum fator predisponente devem ser acompanhados por meio de exame radiográfico de rotina e, quando necessário, o clínico pode solicitar tomada tomográfica para avaliar a extensão e localização da reabsorção, bem como, definir o tratamento adequado para cada caso.

Introduction: External cervical resorption (ECR) is a progressive and aggressive destruction of tooth structure, characterized by the cervical location and the presence of fibrovascular tissue filling the reabsorbed region. The ETS does not present a specific etiology, although there are some predisposing factors to occur. Due to the absence of symptoms, the external cervical resorption turns out to be a radiographic finding, being detected in routine tests. Sometimes, may occur the communication of the lesion with the root canal and develop symptoms related to pulpite. In othercases, clinically the ECR can only be identified as a pink spot at the gingival margin of the crown of the affected tooth. Besides the conventional radiographic technique,it is important for the correct diagnosis of ECR perform the cone beam computed tomography to evaluate the exact extent and location of the lesion. The treatment will depend on the evolution stage of resorption, and even with the application of materials such as MTA, the ECR has a dubious prognosis in most cases. Aim: review the literature about the etiology, diagnosis and treatment of external cervical resorption. Conclusion: External cervical resorption detected the sooner the better your prognosis. Patients who have some predisposing factor must be accompanied by routine radiographic examination and, where necessary, the clinician may request tomographic taking to assess the extent and location of resorption, as well as define the appropriate treatment for each case.

Analysis of the interface and bond strength of resin-based endodontic cements to root dentin.

This study evaluated by scanning electron microscopy the interface between root dentin and resin cements, with or without additional application of a dual-cured one-step self-etching dentin adhesive. In addition, the push-out bond strength of these materials to dentin was evaluated. Root canals of 50 maxillary human canines were subjected to biomechanical preparation and randomly assigned into five groups (n = 10) according to the obturation employed: I. AH Plus/gutta-percha; II. Endo-REZ/gutta-percha; III. Epiphany SE/Resilon; IV. Endo-REZ/gutta-percha + adhesive; and V. Epiphany SE/Resilon + adhesive. After obturation, two cross sections of 1.0 mm of each third of the root were obtained and analyzed by SEM and push-out. Data were analyzed by Kruskal-Wallis, Two-way ANOVA and Tukey's HSD tests (α = 5%). Significant differences occurred between scores for gap parameters and tags; greater tag formation resulted for Epiphany SE (P < 0.05). There were also significant differences between groups for the bond strength. AH Plus (1.24 ± 0.70) showed higher values (P < 0.05) compared to groups II (0,17 ± 0.19), III (0.10 ± 0.06), IV (0.09 ± 0.08), and V (0.06 ± 0.03), which were statistically similar (P > 0.05). There was no significant difference between the root thirds (P > 0.05). It was concluded that the use of a self-etching adhesive system did not improve the adhesion of resin-based sealers to dentin and that AH Plus showed better bond strength when compared to other cements.

Avaliação da capacidade de dissolução tecidual de diferentes soluções de hipoclorito de sódio em tecido conjuntivo e muscular de ratos / Evaluation of capacity of tissue dissolution of various solutions of sodium hypochlorite in connective and muscle tissue of rats

Analisar a capacidade de dissolução tecidual de diferentes soluções de hipoclorito de sódio em tecido conjuntivo e muscular esquelético de ratos.Metodologia: foram obtidos 60 fragmentos de tecido conjuntivo (dorso) e muscular esquelético (língua) de ratos da linhagem Wistar, que foram submetidos à ação solvente das soluções de hipoclorito de sódio comercializadas, prontas para uso, Hipoclor 1%, HW 1% e 2,5%, Limpa Bem 2,5% e soluções manipuladas nas mesmas concentrações. O tempo de dissolução foi cronometrado. O método de titulometria com iodo foi utilizado para confirmação do teor de cloro ativo das soluções utilizadas.Resultados: a análise estatística revelou diferença não significante entre os dois diferentes tecidos (p>0.05) e apresentou diferença significante (p<0.001) entre as concentrações de 1% e 2,5%. O tempo médio de dissolução em minutos no tecido conjuntivo foi: Limpa Bem 2,5% (80,4); Manipulado 2,5% (100,2); Hipoclor 1% (164,2); HW 2,5% (205,6); Manipulado 1% (278,4). No tecido muscular esquelético o tempo médio foi: Limpa Bem 2,5% (111,6); Manipulado 2,5% (171,6); Hipoclor 1% (178,5); HW 2,5% (219); Manipulado 1% (289,6). O HW 1% não foi capaz de dissolver os tecidos. Os resultados da titulometria demonstraram que as soluções testadas apresentavam teor de cloro ativo aceitáveis, com exceção da marca HW nas concentrações de 1% e 2,5%.Conclusão: ambos tecidos podem ser utilizados para a verificação da capacidade de dissolução tecidual do hipoclorito de sódio e que esta obedece uma relação diretamente proporcional a concentração do teor de cloro ativo...

The aim of this study was to analyze the ability of different solutions of sodium hypochlorite to dissolve connective and skeletal-muscle tissue of rats. Methodology: it was obtained 60 pieces of connective tissue (back) and skeletal-muscle (tongue) of Wistar rats that were subjected to solvent action of sodium hypochlorite solutions marketed, ready to use, 1% Hipoclor, 1 and 2, 5% HW, 2.5% Limpa Bem and solutions manipulated at the same concentrations. The dissolution time was recorded. The method of titration with iodine was used to confirm the active chlorine content of solutions used. Results: statistical analysis revealed no significant difference between the two different tissues (p> 0.05) and significantly difference (p <0.001) between concentrations 1% and 2.5%. The average time in minutes to dissolve the connective tissue was: 2.5% Limpa Bem (80.4); 2.5% Manipulated (100.2); 1% Hipoclor (164.2), 2.5% HW ( 205.6); 1% Manipulated (278.4). In skeletal muscle the average time was: 2.5% Limpa Bem (111.6); 2.5% Manipulated (171.6); 1% Hipoclor (178.5), 2.5% HW (219); 1% Manipulated (289.6). The 1% HW was not able to dissolve the tissues. The results of titrations demonstrated that the solutions tested had acceptable levels of chlorine, with the exception of brand HW concentrations of 1% and 2.5%.Conclusion: both tissues can be used for verifying the ability of tissue dissolution of sodium hypochlorite and that obeys a directly proportional to the concentration of active chlorine content...

Opinião de graduandos após 5 anos de experiência com instrumentos endodônticos rotatórios / Undergraduates' opinion after 5-year experience with rotary endodontic instruments

Introdução: A evolução da odontologia nos últimos anos revolucionou a prática diária em algumas especialidades. Uma dessas revoluções ocorreu na Endodontia devido ao avanço das técnicas rotatórias de preparo do canal radicular e sua posterior incorporação ao ensino dos graduandos de Odontologia. Objetivo: O objetivo deste estudo foi relatar uma experiência de 5 anos na graduação laboratorial e clínica do preparo endodôntico rotatório em uma universidade privada. Material e métodos: O levantamento dos dados foi realizado por meio de um questionário composto por nove questões objetivas; o questionário foi respondido pelos graduandos. Resultados: Os resultados mostraram uma aceitação positiva em relação ao ensino da técnica rotatória na graduação (94,7%). As seguintes vantagens foram destacadas: preparo mais rápido do canal radicular (91,6%) e redução do estresse do paciente (80,9%). Conclusão: Pode-se concluir que a experiência com as duas turmas de graduação foi excelente devido ao alto nível de aceitação da nova técnica pelos alunos

Introduction: Dentistry evolution in the past few years has revolutionized daily practice in some specialties. One of these revolutions has occurred in Endodontics due to the advancement of rotary techniques for root canal preparation and its subsequent incorporation into the teaching of Dentistry undergraduates. Objective: The aim of this study was to report a 5-year experience on the undergraduate laboratorial and clinical use of rotary endodontic preparation at a private university. Material and methods: Data survey was performed by using a questionnaire composed of nine objective questions; the questionnaire was answered by the undergraduates. Results: The results showed a positive acceptance regarding the undergraduate teaching of the rotary technique (94.7%). The following advantages were highlighted: faster root canal preparation (91.6%) and reduction of patient's stress (80.9%). Conclusion: It can be concluded that the experience with the two undergraduate groups was excellent due to the high acceptance level of the new technique by the students

Evaluation of professors and students knowledge on crown-root fractures

Objective: The aim of this study was to evaluate the knowledge on crownrootfractures among professors and students of a school of dentistry.Material and methods: A questionnaire comprising the treatment optionsfor crown-root fractures at different depths and their follow-up periodswas applied to 122 subjects divided into three groups: 1) students whohad not attended any Endodontics and Surgery disciplines, 2) studentswho had concluded these disciplines; and 3) professors. The data wasanalyzed by descriptive statistics. Results: Most of Group 1 (90.3%) didnot know the procedures to be adopted in cases of crown-root fractures.Conversely, more than 80% of Group 2 and 95% of Group 3 knew theprocedures. Concerning to crown-root fractures up to 2mm deep, 26.9%of Group 1 and 48.5% of Group 3 would perform crown lengthening;46.2% of Group 2 would perform fragment rebonding. In relation tofractures between 2 and 4mm deep, 21.2% of Group 1 would performtooth extraction; 28.6% of Group 2, fragment rebonding; and 40.7%of Group 3, orthodontic extrusion. In fractures more than 4mm deep,most members of all groups would perform tooth extraction followed byimplant. With regard to follow-up appointments, most members of allgroups stated that their frequency should be at every 6 months (duringthe first year) and every year (for 5 years). Conclusion: Students of Group1 showed poor knowledge on crown-root fractures, while members ofGroups 2 and 3 showed a proper knowledge.

Adhesion of endodontic sealers to human root dentine submitted to different surface treatments.

OBJECTIVE: To evaluate the adhesion of the endodontic sealers Epiphany, Apexit Plus, and AH Plus to root canal dentin submitted to different surface treatments, by using the push-out test. METHODS: One hundred twenty-eight root cylinders obtained from maxillary canines were embedded in acrylic resin, had the canals prepared, and were randomly assigned to four groups (n = 32), according to root dentin treatment: (I) distilled water (control), (II) 17% EDTAC, (III) 1% NaOCl and (IV) Er:YAG laser with 16-Hz, 400-mJ input (240-mJ output) and 0.32-J/cm(2) energy density. Each group was divided into four subgroups (n = 8) filled with Epiphany (either dispensed from the automix syringe supplied by the manufacturer or prepared by hand mixing), Apexit Plus, or AH Plus. Data (MPa) were analyzed by ANOVA and Tukey's test. RESULTS: A statistically significant difference (p < 0.01) was found among the root-canal sealers, except for the Epiphany subgroups, which had statistically similar results to each other (p > 0.01): AH Plus (4.77 +/- 0.85), Epiphany/hand mixed (3.06 +/- 1.34), Epiphany/automix syringe (2.68 +/- 1.35), and Apexit Plus (1.22 +/- 0.33). A significant difference (p < 0.01) was found among the dentin surface treatments. The highest adhesion values were obtained with AH Plus when root dentin was treated with Er:YAG laser and 17% EDTAC. Epiphany sealer presented the lowest adhesion values to root dentin treated with 17% EDTAC. CONCLUSIONS: The resin-based sealers had different adhesive behaviors, depending on the treatment of root canal walls. The mode of preparation of Epiphany (automix syringe or hand mixing) did not influence sealer adhesion to root dentin.

Knowledge and attitudes toward dental avulsion of public and private elementary schoolteachers.

PURPOSE: The purpose of this study was to evaluate and compare the knowledge and attitudes toward dental avulsion of public and private elementary schoolteachers. METHODS: the study was performed by applying a questionnaire in a sample composed of 95 elementary schoolteachers (46 from public schools and 49 from private schools). The questionnaire comprised 9 questions and was pretested before final implementation. RESULTS: Thirty-nine percent of private schoolteachers and 15% of public schoolteachers witnessed at least 1 case of dental avulsion at the school (P=.009). Ninety-two percent and 62% of private and public schoolteachers, respectively, admitted the possibility of an avulsioned tooth to be reimplanted (P<.001). Both responses were statistically different when school type (public or private) was considered. Only 27% of private schoolteachers and 11% of public schoolteachers knew the procedures to be taken in cases of avulsed teeth, and more than 95% of all teachers did not feel capable of executing tooth reimplantation. The study showed no statistical difference between private and public schoolteachers' knowledge. CONCLUSIONS: Teachers and other professionals involved in children's care and supervision must be correctly and well informed about dental avulsion, its consequences and the correct procedures to be performed in such cases.

Etiologia e prevenção das reabsorções cervicais externas associadas ao clareamento dentário / Etiology and prevention of external cervical root resorption associated to teeth bleaching

Introdução e objetivo: A estética na Odontologia tem sido priorizada, eo desejo por dentes mais claros tem estado cada vez mais presente nos consultórios, pois dentes mais brancos tendem a demonstrar saúde,beleza, jovialidade e tornam o sorriso mais atraente. O clareamento dental é um meio conservador amplamente utilizado para restabelecer a cor natural de dentes escurecidos, no entanto uma provável relação com a reabsorção externa cervical tem preocupado muitos pesquisadores e clínicos. Revisão de literatura: Vários são os mecanismos que podem desencadear essa reabsorção, entre eles a ação química e física dos agentes clareadores empregados, a morfologia da junção amelocementária associada ao sistema imunológico, a concentração dos materiais empregados, os traumas, bem como a técnica de clareamento utilizada. Conclusão: Diante de diferentes fatores, aindanão conclusivos, prevenindo efeitos deletérios para dentes e estruturas de suporte, cuidados devem ser tomados na escolha do agente clareador,da técnica de aplicação e também dos casos, além da confecção de uma restauração adequada após o clareamento dental.

AbstractIntroduction and objective: Esthetic dentistry has been prioritized and the desire for whiter teeth has been increasingly present in dental offices, since whiter teeth tend to indicate health, beauty, youth and a more attractive smile. Teeth bleaching is a conservative method widely used to restore the original color of darkened teeth. However, possible relations with the external cervical root resorption have concerned many researchers and clinicians. Literature review: There are many mechanisms that can activate the external cervical root resorption,such as: chemical and physical action of the bleaching materials used,morphology of the cementoenamel junction associated to the immune system, material concentration, traumas and bleaching technique used. Conclusion: Therefore, considering many factors that are still not conclusive, preventing deleterious effects on teeth and support structures, care must be taken when choosing bleaching agent and bleaching technique, as well as when selecting each case, beyond aproper restoration after teeth bleaching.

Avaliação in vitro da ação antimicrobiana de alguns cimentos endodônticos / In vitro evaluation of the antimicrobial activity of some endodontic sealers

Introdução: Ao realizar o tratamento endodôntico, o cirurgião-dentista deve utilizar meios para eliminar ou reduzir o número de bactérias situadas no interior do canal radicular em casos de necrose pulpar. Objetivo: Avaliar a ação antimicrobiana dos cimentos endodônticos Endofill, Sealer 26, AHPlus e Acroseal. Material e métodos: A avaliação foi feita pelo método de estudo de difusão em ágar, em placas previamente inoculadas com os microrganismos E. coli, E. faecalis, B. cereus e S. aureus. Após 48 horas de incubação em estufa a 37ºC, realizou-se leitura do diâmetro do halo de inibição do crescimento microbiano. Resultados: O cimento Acroseal mostrou atividade antimicrobiana ausente contra E. coli e E. faecalis e moderada contra B. cereus e S. aureus; o AHPlus e o Endofill evidenciaram alto poder antimicrobiano principalmente contra E. coli; o Sealer 26 apresentou moderada ação antimicrobiana contra todos os microrganismos empregados. Conclusão: A maioria dos cimentos endodônticos avaliados demonstrou atividade antimicrobiana contra os microrganismos usados. Os cimentos AHPlus e Endofill tiveram maior poder antimicrobiano.

Introduction: When performing endodontic treatment, the dental surgeon must find ways to eliminate or reduce the microorganisms situated in the root canal in cases of pulpal necrosis. Objective: To analyze the antimicrobial action of Endofill, Sealer 26, AHPlus and Acroseal endodontic sealers. Material and methods: Evaluation was made by Agar diffusion method in plates previously inoculated with the following microorganisms: E. coli, E. faecalis, B. cereus and S. aureus. The zones of inhibition were measured after 48 hours of incubation at 37°C. Results: Acroseal sealer showed no antimicrobial activity against E. coli and E. faecalis and it showed moderate activity against B. cereus and S. aureus; AHPlus and Endofill showed high activity mainly against E. coli; Sealer 26 showed moderate activity against all of the microorganisms used. Conclusion: The majority of endodontic sealers have showed antimicrobial activity against the microorganisms used. AHPlus and Endofill sealers were the ones that showed greater antimicrobial activity.

Capacidade seladora do agregado de trióxido mineral em perfurações de furca após irrigação final com diferentes soluções / Mineral trioxide aggregate sealing ability in furcal perforations after final irrigation with different solutions

Introdução - O presente estudo avaliou a influência de diferentes soluções irrigadoras na capacidade seladora do MTA quando utilizado em perfurações na região de furca de molares inferiores extraídos. Material e Métodos - Trinta molares inferiores humanos foram submetidos à abertura endodôntica convencional e tiveram o centro do assoalho perfurado propositalmente com broca esférica diamantada. Os espécimes foram divididos em 3 grupos (n = 10) de acordo com as soluções utilizadas: G1-soro fisiológico; G2-NaOCl a 1% e G3-EDTA 17%. Foi realizado o preenchimento da perfuração com MTA Angelus cinza e o selamento coronário provisório. Em seguida,realizou-se a impermeabilização da superfície externa, exceto na região de furca, e imersão em corante nanquim por 72 horas. A mensuração, em milímetros, da infiltração linear foi realizada por meio do software Image Tool. Resultados - Os resultados demonstraram que a solução de EDTA 17% permitiu menor infiltração, sendo estatisticamente diferente do NaOCl a 1% e do soro fisiológico(p < 0,05). Conclusão - De acordo com os resultados, pode-se concluir que a solução de EDTA parece ser a melhor escolha para irrigação final em casos de perfuração de furca.

Introduction - This study assessed the influence of different final irrigation on the sealing ability of MTA-Angelus in furcal perforations of extracted human molar teeth. Material and Methods - Thirty human mandibular molars were conventionally accessed and perforations were purposely created in the center of the pulp chamber floor by using a round diamond bur. The specimens were divided into 3 groups (n = 10) according to the irrigation: G1-saline solution; G2-1% sodium hypochlorite; G3-17% EDTA. Teeth were repaired with Angelus'gray MTA and the crowns were sealed.Then the impermeabilization of the external surface was made except in the furcal region, and they were immersed into Indian Ink for 72 hours. The leakage was measured, in millimeters, by Image Tool software. Results - The results showed lower leakage index for EDTA group that was statistically different from 1% NaOCl and saline solution groups (p < 0.05). Conclusion - According to results it can be concluded that in cases of furcal perforation EDTA solution seems to be the best choice of final irrigation.

Analysis of the internal anatomy of maxillary first molars by using different methods.

The success of endodontic treatment depends on the identification of all root canals so that they can be cleaned, shaped, and obturated. This study investigated internal morphology of maxillary first molars by 3 different methods: ex vivo, clinical, and cone beam computed tomography (CBCT) analysis. In all these different methods, the number of additional root canals and their locations, the number of foramina, and the frequency of canals that could or could not be negotiated were recorded. In the ex vivo study, 140 extracted maxillary first molars were evaluated. After canals were accessed and detected by using an operating microscope, the teeth with significant anatomic variances were cleared. In the clinical analysis, the records of 291 patients who had undergone endodontic treatment in a dental school during a 2-year period were used. In the CBCT analysis, 54 maxillary first molars were evaluated. The ex vivo assessment results showed a fourth canal frequency in 67.14% of the teeth, besides a tooth with 7 root canals (0.72%). Additional root canals were located in the mesiobuccal root in 92.85% of the teeth (17.35% could not be negotiated), and when they were present, 65.30% exhibited 1 foramen. Clinical assessment showed that 53.26%, 0.35%, and 0.35% of the teeth exhibited 4, 5, and 6 root canals, respectively. Additional root canals were located in this assessment in mesiobuccal root in 95.63% (27.50% could not be negotiated), and when they were present, 59.38% exhibited 1 foramen. CBCT results showed 2, 4, and 5 root canals in 1.85%, 37.05%, and 1.85% of the teeth, respectively. When present, additional canals showed 1 foramen in 90.90% of the teeth studied. This study demonstrated that operating microscope and CBCT have been important for locating and identifying root canals, and CBCT can be used as a good method for initial identification of maxillary first molar internal morphology.

Análise radiográfica da trajetória do quarto canal no primeiro molar superior / Radriographic analysis of the trajectory of the fourth canal in first maxillary molar

O objetivo deste trabalho foi avaliar radiograficamente a trajetória do canal mesiopalatino em primeiros molares superiores, visando verificar a importância da análise radiográfica no tratamento desse grupo de dentes, tendo em vista a grande incidência de dois canais na raiz mesiovestibular. Foram utilizados neste estudo 65 primeiros molares superiores extraídos, doados por alunos da PUC/PR. Os dentes foram radiografados com películas radiográficas periapicais, com 20 graus de angulação na incidência disto-excêntrica e com posicionamento de limas tipo K nº 10 nos canais. A análise buscou distribuir a amostra de acordo com a classificação do sistema de canais radiculares proposta por Weine [7]. O resultado obtido foi: 47,7% (31) do tipo I; 21,5% (14) do tipo II; 12,3% (8) do tipo III; 18,5% (12) calcificados. Pode-se concluir que a análise cuidadosa da raiz mesiovestibular é importante para que se possa assegurar um bom prognóstico ao tratamento

The purpose of this study was to evaluate, by radiographic exam, the trajectory of the mesiopalatal canal in maxillary first molars, aiming at assessing the importance of the radiographic analysis in the treatment of these teeth; due to great incidence of two canals in the mesiovestibular root. Sixty-five extracted maxillary first molars were donated by students of PUC/PR and used in this study. Periapical radiographs of the teeth were taken at 20 degrees in the disto-eccentric incidence and positioning #10 K-type files into the canals. The analysis aimed at distributing the sample according to the classification of root canal system proposed by Weine [7]. The obtained result was: 47.7% (31) ­ type I; 21.5% (14) ­ type II; 12.3% (08) ­ type III and 18.5% (12) ­ calcified. It can be concluded that a careful analysis of the mesiovestibular root is important to guarantee a good prognostic of the treatment