Genotoxicity in the oral cells of older people from a Brazilian rural area: a population-based study

Abstract The purpose of this population-based, observational, and cross-sectional study was to evaluate alterations in the oral cells of a population of older people from a Brazilian rural area, using the micronucleus technique to investigate possible associated genotoxic factors. A questionnaire was applied and clinical examination and collection of oral mucosal cells were performed for all older people (≥ 60 years) from a town in southern Brazil. Demographic and socioeconomic variables, deleterious habits (drinking and tobacco use), presence of gastro-oesophageal reflux disease (GERD), and the use of proton pump inhibitors (PPIs) were considered the exposure variables, whereas metanuclear changes (MCs) and the prevalence of cell micronuclei (MN) were considered outcomes. Out of 489 older people, 447 were included in the study, among whom 50.8% were men with a mean age of 70.9 years and 83.9% had a monthly family income greater than US$ 500.00. GERD symptoms were present in 36.2% of the individuals, and 29.1% used PPIs daily, 53.3% consumed alcoholic beverages, and 46.7% used tobacco. The analysis of 1,000 oral mucosal cells per subject showed a MN frequency of 0-2 per individual, and MCs were detected with an average of 15 units per individual (median = 11 per individual). Poisson regression did not show statistical association between the exposure variables and the outcomes (presence of MN and MCs), except for the use of PPIs, which was a protective factor for the prevalence of MN [PR 0.6 (CI 0.3-0,9)]. Age, sex, family income, tobacco use and drinking, and GERD were not associated with the number of MN and MCs in oral mucosal cells of the investigated older people.

A atuação da Odontologia em unidades de terapia intensiva no Brasil / The practice of dentistry in intensive care units in Brazil

RESUMO Objetivo: Avaliar a atuação odontológica em unidades de terapia intensiva. Métodos: Estudo observacional de enquete, por meio do envio de questionários via plataforma on-line de colaboração de pesquisa em terapia intensiva no Brasil (AMIBnet). A pesquisa foi realizada de junho a outubro de 2017. Os questionários, envolvendo 26 questões fechadas sobre os hospitais e a atuação odontológica nas unidades de terapia intensiva foram enviados para 4.569 profissionais de diversas especialidades atuantes nas unidades. Resultados: Obtivemos 203 questionários respondidos, resultando em uma taxa de resposta de 4,44%. A maior parte das respostas teve origem em unidades de terapia intensiva na Região Sudeste do país (46,8%). Hospitais públicos (37,9%) e privados (36,4%) tiveram participação semelhante nos resultados. Dos respondentes, 55% apontaram que um serviço de Odontologia à beira de leito estava presente, sendo prestado de maneiras diversas. Conclusão: Presença de Serviço de Odontologia e de treinamentos e protocolos de prestação de serviço em saúde bucal estiveram correlacionados. Os métodos de cuidados orais variaram sobremaneira entre as em unidades de terapia intensiva pesquisadas.

ABSTRACT Objective: To evaluate the practice of dentistry in intensive care units. Methods: An observational survey study was conducted in which questionnaires were sent via the online platform for collaboration in intensive care research in Brazil (AMIBnet). The study was carried out from June to October 2017. The questionnaires, which contained 26 closed questions about hospitals and dentistry practices in the intensive care units, were sent to 4,569 professionals from different specialties practicing in the units. Results: In total, 203 questionnaires were returned, resulting in a response rate of 4.44%. Most of the responses were from intensive care units in the Southeast region of the country (46.8%). Public hospitals (37.9%) and private hospitals (36.4%) had similar participation rates. Of the respondents, 55% indicated that a bedside dentistry service was present, and they were provided in different ways. Conclusion: The presence of dentistry services and oral health service delivery training and protocols were correlated. The oral care methods varied greatly among the intensive care units surveyed.

Influence of Different Intellectual Disability Levels on Caries and Periodontal Disease

Abstract Oral health care is fundamental to preserve the individual integrity and consequently influences the general health. This observational, cross-sectional and analytical study evaluated the oral condition of 129 intellectually disabled individuals from the Association of Parents and Friends of Exceptional Children (APAE) in three southern Brazilian cities. Dental caries (DMFT and dmft indices) and periodontal disease (PSR index) were evaluated considering the intellectual disability level. A questionnaire on socioeconomic status (income and education level) and the last visit to a dentist was answered by the subjects' parents/guardians. The data were statistically evaluated using analysis of variance (ANOVA) and Tukey test (α=0.05). The mean DMFT values were 2.27, 3.76 and 0.58 (p<0.05), and the mean dmft values were 1.48, 1.55 and 2.75, respectively for subjects with mild, moderate and severe disabilities. Regarding the PSR index, 43% of the subjects presented gingivitis without retention factor (no calculus or defective margins) with no significant differences among the three disability levels. Considering the population and the limitations of this study, the subjects presenting severe disabilities showed significantly lower mean DMFT values compared to other disability levels, probably because the caretakers are responsible for the oral hygiene of such subjects.

Resumo Os cuidados com a saúde bucal são de fundamental importância para a preservação da integridade do indivíduo e, consequentemente, refletem na saúde geral. Este estudo transversal, observacional e analítico avaliou a situação bucal de 129 alunos com deficiência intelectual matriculados na Associação de Pais e Amigos dos Excepcionais (APAE) de três municípios do sul do Brasil. Cárie dentária (índices CPO-D e ceo-d) e doença periodontal (índice PSR) foram avaliados considerando o nível de deficiência intelectual. Um questionário das condições socioeconômicas (renda e escolaridade) e última visita ao dentista foi respondida pelos pais/responsáveis. Os dados foram avaliados estatisticamente utilizando análise de variância (ANOVA) e teste Tukey (α=0,05). As médias no índice CPO-D foram de 2,27, 3,76 e 0,58 (p<0,05) e no índice ceo-d foram de 1,48, 1,55 e 2,75 para os alunos com deficiência leve, moderada e severa, respectivamente. Com relação ao índice PSR, 43% dos alunos apresentou gengivite sem fator de retenção (sem cálculo ou defeitos marginais), não tendo diferença estatística entre os três níveis de deficiência. Considerando a população e as limitações do estudo, observou-se que alunos com deficiência severa apresentaram índice CPO-D significativamente menor comparado com outros níveis de deficiência, provavelmente devido à higiene oral ser realizada pelos cuidadores/responsáveis.

Accuracy of color measurement of endondontically treated teeth after aging / Precisão da medição de cor de dentes tratados endodonticamente após envelhecimento

Objective: The aim of this study was to compare the accuracy of three different modes of a spectrophotometer (Vita Classical, 3D-Master and CIE L*a*b* system) in the evaluation of color alteration in endodontically treated teeth. Material and Methods: The root canal treatment of forty-five sound human canines was performed. Color measurements were performed before the endodontic treatment (baseline), and after 6 months of water storage. Shade matching was performed using a spectrophotometer (Vita Easyshade) in three different modes: Vita Classical, 3D-Master and CIE L*a*b* coordinates. The color change (ΔE value) for the three methods were assessed in each sample and analyzed by multiple linear regression analysis. L*, a* and b* values were analyzed by t-test. The significance level was set at 5%. Results: According to the digital evaluation, no statistically significant differences were found between the CIE L*a*b*,Vita Classical and 3D-Mastermodes. However, a significant difference was found (p < 0.001) for the ΔE values, with the CIE L*a*b* mode presenting greater accuracy to detect color alterations. Conclusion: CIE L *a*b* method properly correlates to Vita Classical and 3D-Master modes. However, Easyshade can easier detect color changes if used in the CIE L*a*b* mode, which leads to more accurate results.

Objetivo: O objetivo deste estudo foi comparar a precisão de três modos diferentes de um espectrofotômetro (Vita Classical, 3D-Master e sistema CIE L*a*b*) na avaliação da alteração de cor em dentes tratados endodonticamente. Materiais e Métodos: O tratamento endodôntico de quarenta e cinco caninos humanos foi realizado. Medições de cor foram realizadas, antes do tratamento endodôntico (imediatamente), e após 6 meses de armazenamento em água. Análise de cor foi realizado utilizando um espectrofotômetro (Vita Easyshade) em três diferentes modos: Vita Classical, 3D-Master e sistema CIE L*a*b*. A mudança de cor (valor ΔE) para os três métodos foram avaliadas em cada amostra e analisados através de análise de regressão linear múltipla. Valores de L*, a* e b* foram analisados através do teste-t. O nível de significância estabelecido foi de 5%. Resultados: De acordo com a avaliação digital, não foram encontradas diferenças significativas entre os métodos CIE L*a*b*,Vita Classical e 3D-Master. No entanto, uma diferença significativa foi encontrada (p < 0,001) para os valores de ΔE, com o modo CIE L*a*b* apresentando uma maior precisão para detectar alterações de cor. Conclusão: O método CIE L *a*b* correlaciona corretamente para os modos Vita Classical e 3D-Master. No entanto, o Easyshade pode detectar alterações de cor, mais facilmente quando utilizado no modo CIE L *a*b*, permitindo resultados mais precisos.

Uso de fibrina rica em plaquetas (PRF) no tratamento de perfurações da membrana sinusal / Use of platelet-rich fibrin (PRF) to treat sinus membrane perforations

A reabilitação de áreas edântulas sempre foi um desafio para os profissionais, em especial a posterior de maxila, pela pneumatização dos seios maxilares. Uma das complicações durante os procedimentos de levantamento sinusal são as perfurações da membrana. A fibrina rica em plaquetas (PRF), um concentrado de fatores de crescimento obtido a partir da centrifugação do sangue do paciente, tem a propriedade de acelerar o processo cicatricial, reparar as perfurações na membrana schneideriana e funcionar como material de preenchimento. O objetivo do presente estudo foi revisar a literatura e relatar um caso de selamento de perfuração de membrana sinusal utilizando membrana de fibrina (PRF) associada … hidroxiapatita bovina

Rehabilitation of edentulous areas has always been a challenge for dentists, especially on the posterior maxilla due to the pneumatization of the maxillary sinus. One of the complications during sinus lifting procedures is perforation of the membrane. The platelet-rich fibrin (PRF) is a complex of growth factors obtained from centrifuging the patient’s blood. It has the ability to accelerate the healing process and repair damages in the Schneiderian membrane, therefore, functioning as a filling material. The aim of this study was to perform a literature review and report a clinical case of sealing membrane perforation using PRF associated with bovine hydroxyapatite

Atendimento odontológico de pacientes surdo-cegos: enfrentando desafios / Dental care for deafblind patients: facing challenges

Introdução: a odontologia tem um papel muito importante na atenção à saúde dos pacientes surdo-cegos, porém, esbarra na falta de profissionais qualificados e estudos específicos nessa área. Objetivo: essa revisão de literatura tem por objetivo apresentar aos profissionais da odontologia informações sobre a surdo-cegueira, descrevendo conceitos, causas e classificações, assim como relatar os métodos de comunicação, a necessidade da inserção do odontólogo na equipe multiprofissional de atendimento aos surdo-cegos, definindo, por fim, metodologias que auxiliem no atendimento odontológico desses pacientes. Revisão de literatura: a atuação do cirurgião-dentista na equipe multiprofissional proporciona aos pacientes melhorias no seu desenvolvimento, por meio da criação de vínculos e de atividades que propiciem maior autonomia. Além disso, demonstra a deficiência de informação na área da surdo-cegueira, sendo o envolvimento da família fator fundamental para um prognóstico favorável no processo educacional, social e de comunicação. Considerações finais: o profissional, além do conhecimento técnico e científico em sua área de atuação, deve ter domínio do melhor meio de comunicação com seu paciente surdo-cego.

Evidências científicas para o diagnóstico e tratamento da DTM e a relação com a oclusão e a ortodontia / Scientific evidence for the diagnosis and treatment of TMD and its relation to occlusion and orthodontics

Introdução: Vários conceitos envolvem a etiologia da DTM e a relação com a oclusão e a ortodontia, o que tem sido objeto de discussão e controvérsias, dificultando o diagnóstico e a construção de uma terapêutica eficiente para a disfunção. O relacionamento dessas três áreas tem sido amplamente questionado e é muito provável que uma mudança de paradigma esteja acontecendo com relação à DTM. Revisão de literatura: A etiologia é complexa e multifatorial, por isso, a tentativa de isolar uma causa universal não tem sido bem-sucedida. Os sinais e sintomas podem se manifestar de várias formas e, ainda, terapias inadequadas podem gerar iatrogenias, permitindo a cronificação da sintomatologia. O objetivo deste trabalho foi apresentar as informações existentes sobre o universo da DTM, considerando seu caráter fisiológico, etiológico, métodos diagnósticos e as diferentes formas de tratamento. Além disso, apresenta possíveis relações com outras áreas da odontologia, especialmente a oclusão e a ortodontia, por meio de uma revisão de literatura em bases de dados nacionais e internacionais (PubMed, Scielo, Bireme e Google Acadêmico). Considerações finais: Embora controversas, as evidências científicas parecem não suportar a relação ortodontia/DTM, bem como a relação oclusão/DTM. Apesar disso, é importante ressaltar que os tratamentos oclusal e ortodôntico, corretamente conduzidos, tem papel imprescindível na odontologia, pois estão envolvidos em diversos outros aspectos relevantes para a função e estética do sistema estomatognático e, portanto, não devem ser negligenciados pelos profissionais da odontologia.

Histopathological analysis of corticosteroid-antibiotic preparation and propolis paste formulation as intracanal medication after pulpectomy: an in vivo study

Intracanal medication in pulpectomy therapy is used between appointments with the objective of reducing pain and inflammatory processes in pulp and periapical tissues. Propolis has been known as a natural antibiotic and has been subject of medical and dental research due to its therapeutic properties such as antibiotic, analgesic and anti-inflammatory effects. OBJECTIVE: The aim was to carry out an in vivo evaluation of the periapical tissue response to propolis paste when used as an intracanal medication in the teeth of dogs after pulpectomy. MATERIAL AND METHODS: 72 dog's incisors were selected for the experiment. After biomechanical preparation the root canal was filled with a corticosteroid-antibiotic preparation, experimental propolis paste, non-medicament (negative control) or non-pulpectomy at all (positive control). The medications were left inside the root canal for 7, 14 or 28 days. At the end of the experimental period histological sections were prepared and all laboratories processes for Harris hematoxylin and eosin staining was proceeded followed by the analysis using an optical microscope. Sections were classified according to a score representing the inflammatory events observed: the presence of polymorphonuclear neutrophils, polymorphonuclear eosinophils, lymphocytes and plasma cells, macrophages and/or giant cells, fibrous condensation and abscesses. RESULTS: There were statistically significant differences between the tissue reactions caused by the two substances being tested, after different experimental periods, with the periapical tissue that was in contact with propolis paste exhibiting fewer inflammatory reactions in comparison to corticosteroid-antibiotic preparation. CONCLUSIONS: The low tissue responses from propolis paste suggest that this material could be considered as an option for root canal medication after pulpectomy.

Radiographic evaluation of furcal perforations sealed with different materials in dogs' teeth

OBJECTIVE: The objective of this work was to evaluate, using radiographic images, the behavior of four materials used to repair root perforations in dogs' teeth. Material and METHODS: Second and third premolars of 6 dogs were used. The 48 teeth were randomly divided into 4 groups (n=12) and the perforations were sealed with one of the following materials: MTA, AH Plus, Vitremer and gutta-percha. Dogs were submitted to general anesthesia, teeth were radiographed and pulp was accessed. Perforations were done, at the maximum curve of the pulp floor, sealed and the accessed coronal cavity was filled with glass ionomer cement (Vidrion R). After 90 days, the dogs were sacrificed and the last x-ray image was taken. Images were analyzed for the presence/absence of periodontal lesions at the perforation region. Data were analyzed statistically by chi-square test at 5 percent significance level. RESULTS: There were no statistically significant differences (p>0.05) among AH Plus, Vitremer and gutta-percha groups. MTA produced the smallest number of periodontal lesions (p<0.05). CONCLUSIONS: It may be concluded that none of the tested materials was able to preserve the integrity of the periodontal tissues in the furcation region, and the use of MTA resulted in the least formation of adjacent periodontal bone lesions revealed by the radiographic comparisons.

Fluoride Release from Restorative Materials

The aim of this study was to evaluate in vitro fluoride (F) release from 4 restorative materials (3M ESPE): Ketak Molar Easymix [KME - conventional glass ionomer cement (GIC)]; Rely-X luting 2 [RL2 - resin-modified GIC (RMGIC)]; Vitremer (VIT- RMGIC); and Filtek Z250 [Z250 - negative control]. Disc-shaped specimens were fabricated according to the manufacturer’s instructions and placed into 10 mL of reverse osmosis water at 37°C until the analyses were done using a liquid membrane for selective F ion electrode (Orion 710). F release was evaluated every 6 h in the first day and thereafter daily during 28 days (d). The results were analyzed statistically by two-way ANOVA and Tukey’s test (α=0.05). Mean F release and standard deviation values (in ppm) were: KME: 6 h- 0.34 ± 0.04; 24 h- 1.22 ± 0.30; 7 d- 0.29 ± 0.09; 14 d- 0.20 ± 0.04; 28 d- 0.16 ± 0.01; RL2: 6 h- 2.46 ± 0.48; 24 h-12.33 ± 2.93; 7 d- 1.37 ± 0.38; 14 d- 0.80 ± 0.13; 28 d- 0.80 ± 0.21; VIT: 6 h- 0.98 ± 0.35; 24 h- 4.35 ± 1.22; 7 d- 0.66 ± 0.23; 14 d- 0.40 ± 0.07; 28 d- 0.39 ± 0.08; Z250: 6 h- 0.029 ± 0.001; 24 h- 0.024 ± 0.009; 7 d- 0.023 ± 0.004; 14 d- 0.025 ± 0.001; 28 d- 0.028 ± 0.001. RL2 RMGIC released more F than the other materials in all periods. The greatest release of F occurred in the first 24 h.

O objetivo deste estudo foi avaliar, in vitro, a liberação de flúor (F) de 4 materiais restauradores (3M-ESPE): KME cimento de ionômero de vidro convencional (CIV) (Ketak Molar Easymix); RX2- GIC modificado por resina (RMGIC) (Rely-X luting 2); VIT-RMGIC (Vitremer); -resina composta Z250 (controle negativo) (Filtek Z250). As amostras foram confeccionadas de acordo com as instruções do fabricante e colocadas em 10 mL de água destilada 37°C até as leituras, que foram feitas utilizando um eletrodo de íon seletivo de fluoreto de membrana líquida (Orion 710). A liberação de flúor foi avaliada a cada 6 h no primeiro dia e, diariamente durante 28 dias (d). Os resultados foram analisados estatisticamente usando ANOVA a dois critérios e teste de Tukey. A média e desvio padrão de liberação de F, valores (em ppm) foram: KME: 6 h- 0,34 ± 0,04; 24 h- 1,22 ± 0,30; 7 d- 0,29 ± 0,09; 14 d- 0,20 ± 0,04; 28 d- 0,16 ± 0,01; RL2: 6 h- 2,46 ± 0,48; 24 h- 12,33 ± 2,93; 7 d- 1,37 ± 0,38; 14 d- 0,80 ± 0,13; 28 d- 0,80 ± 0,21; VIT: 6 h- 0,98 ± 0,35; 24 h- 4,35 ± 1,22; 7 d- 0,66 ± 0,23; 14 d- 0,40 ± 0,07; 28 d- 0,39 ± 0,08; Z250: 6 h- 0,029 ± 0,001; 24 h- 0,024 ± 0,009; 7 d- 0,023 ± 0,004; 14 d- 0,025 ± 0,001; 28 d- 0,028 ± 0,001. Concluiu-se que RL2 liberou mais F do que os outros materiais em todos os períodos. A maior liberação de F ocorreu nas primeiras 24 h.

Influence of different restorative techniques on marginal seal of class II composite restorations

OBJECTIVE: To evaluate the gingival marginal seal in class II composite restorations using different restorative techniques. MATERIAL AND METHODS: Class II box cavities were prepared in both proximal faces of 32 sound human third molars with gingival margins located in either enamel or dentin/cementum. Restorations were performed as follows: G1 (control): composite, conventional light curing technique; G2: composite, soft-start technique; G3: amalgam/composite association (amalcomp); and G4: resin-modified glass ionomer cement/composite, open sandwich technique. The restored specimens were thermocycled. Epoxy resin replicas were made and coated for scanning electron microscopy examination. For microleakage evaluation, teeth were coated with nail polish and immersed in dye solution. Teeth were cut in 3 slices and dye penetration was recorded (mm), digitized and analyzed with Image Tool software. Microleakage data were analyzed statistically by non-parametric Kruskal-Wallis and Mann-Whitney tests. RESULTS: Leakage in enamel was lower than in dentin (p<0.001). G2 exhibited the lowest leakage values (p<0.05) in enamel margins, with no differences between the other groups. In dentin margins, groups G1 and G2 had similar behavior and both showed less leakage (p<0.05) than groups G3 and G4. SEM micrographs revealed different marginal adaptation patterns for the different techniques and for the different substrates. CONCLUSION: The soft-start technique showed no leakage in enamel margins and produced similar values to those of the conventional (control) technique for dentin margins.

Flexural strength and hardness of direct and indirect composites

The objective of this study was to evaluate the flexural strength (óf) and hardness (H) of direct and indirect composites, testing the hypotheses that direct resin composites produce higher óf and H values than indirect composites and that these properties are positively related. Ten bar-shaped specimens (25 mm x 2 mm x 2 mm) were fabricated for each direct [D250 - Filtek Z250 (3M-Espe) and D350 - Filtek Z350 (3M-Espe)] and indirect [ISin - Sinfony (3M-Espe) and IVM - VitaVM LC (Vita Zahnfabrik)] materials, according to the manufacturer's instructions and ISO4049 specifications. The óf was tested in three-point bending using a universal testing machine (EMIC DL 2000) at a crosshead speed of 0.5 mm/min (ISO4049). Knoop hardness (H) was measured on the specimens' fragments resultant from the óf test and calculated as H = 14.2P/l², where P is the applied load (0.1 kg; dwell time = 15 s) and l is the longest diagonal of the diamond shaped indent (ASTM E384). The data were statistically analyzed using Anova and Tukey tests (á = 0.05). The mean óf and standard deviation values (MPa) and statistical grouping were: D250 - 135.4 ± 17.6a; D350 - 123.7 ± 11.1b; ISin - 98.4 ± 6.4c; IVM - 73.1 ± 4.9d. The mean H and standard deviation values (kg/mm²) and statistical grouping were: D250 - 98.12 ± 1.8a; D350 - 86.5 ± 1.9b; ISin - 28.3 ± 0.9c; IVM - 30.8 ± 1.0c. The direct composite systems examined produce higher mean óf and H values than the indirect composites, and the mean values of these properties were positively correlated (r = 0.91), confirming the study hypotheses.

Triângulo de Bonwill e sua relação com o gênero e o tipo de oclusão dos pacientes / Bonwill´s triangle and its relation with the genre and occlusion type of patients

O triângulo de Bonwill (TB) é formado por linhas imaginárias unindo: o ponto interincisivo (PI), o côndilo direito (CD)e o esquerdo (CE). O objetivo foi relacionar o TB com o gênero das pessoas e o tipo de oclusão, testando a hipótese de que o tipo de oclusão altera as medidas desse triângulo. Foram examinadas 140 pessoas (P), sendo 56 homens (H) e 84 mulheres (M), entre 18 e 32 anos, que tiveram o tipo de oclusão determinada (Angle). Os registros do PI e da distânciaintercondilar foram realizados pelo arco facial (Bio-art). As medidas entre PI-CE-CD foram registradas e os valoresanalisados estatisticamente usando Anova e Tukey (α=0,05). A oclusão tipo I ocorreu em 97P (42H e 55M), a tipo II-1 em 35P (10H e 25M), a tipo II-2 em 6P (3H e 3M) e a tipo III em 2P (1H e 1M). Levando em consideração o sexo das P, as distâncias médias (mm) entre os 3 pontos foram: H= 124.7±7.8a; 121.9±4.5b; 121.5±4.5b e M=117.8±4.7A; 114.8±4.6B;114.5±4.2B. Considerando o tipo de oclusão: I=120.3±7.3; 118.1±5.6; 117.8±5.5; II-1= 120.8±6.3; 116.1±5.8; 116.1±5.5;II-2= 122.1±6.3; 118.3±5.9; 117.8±4.3; III= 121.5±4.9; 116.5±10.6; 115.0±11.3. Houve diferença significante entre as 3medidas dos H e M e entre as mesmas medidas nos H e nas M (p<0,05), sugerindo que o TB não é eqüilátero e é diferente para H e M, na população estudada. Considerando a amostragem, o tipo de oclusão não influenciou significativamente na medida dos lados do triângulo (p>0,05), rejeitando a hipótese inicial.

The Bonwill’s triangle (TB) is formed by imaginary lines joining the inter-incisive point (PI), the right condyle (CD) andthe left condyle (CE). The objective was to relate the TB to people’s genre and the type of occlusion, testing the hypothesis that the type of occlusion modifies the triangle measurements. One hundred forty people (P) were examined, 56 men (H) and 84 women (M), 18-32 years old, whose type of occlusion was determined using Angle’s classification. The PI and inter-condyle distance registers were obtained using a face bow (Bio-art). The PI-CE-CD measurements were recorded and statistically analyzed using one-way Anova and Tukey (α=0,05). Type I occlusion occurred in 97P (42H and 55M), type II-1 appeared in 35P (10H and 25M), type II-2 in 6P (3H and 3M) and type III in 2P (1H and 1M). Considering the people’s genre, the mean and standard deviation values of the PI-CE-CD measurements (mm) were: H=124.7±7.8a; 121.9±4.5b; 121.5±4.5b and M=117.8±4.7A; 14.8±4.6B; 114.5±4.2B. Considering the type of occlusion the mean values were: I=120.3±7.3; 118.1±5.6; 117.8±5.5; II-1= 120.8±6.3; 116.1±5.8; 116.1±5.5; II-2= 122.1±6.3; 118.3±5.9; 117.8±4.3; III= 121.5±4.9; 116.5±10.6; 115.0±11.3. There was a significant difference among the 3 measurements for H and M and between the same measurements among the H and the M studied (p<0,05), suggesting that the TB is not an equilateral geometric form and it is different between H and M, for the population studied. The type of occlusion did not influence significantly in the measurement of the triangle sides (p>0,05), rejecting the study hypothesis.

Flexural and diametral tensile strength of composite resins

This study evaluated the flexural strength (sf) and the diametral tensile strength (st) of light-cured composite resins, testing the hypothesis that there is a positive relation between these properties. Twenty specimens were fabricated for each material (Filtek Z250- 3M-Espe; AM- Amelogen, Ultradent; VE- Vit-l-escence, Ultradent; EX- Esthet-X, Dentsply/Caulk), following ISO 4049 and ANSI/ADA 27 specifications and the manufacturers’ instructions. For the st test, cylindrical shaped (4 mm x 6 mm) specimens (n = 10) were placed with their long axes perpendicular to the applied compressive load at a crosshead speed of 1.0 mm/min. The sf was measured using the 3-point bending test, in which bar shaped specimens (n = 10) were tested at a crosshead speed of 0.5 mm/min. Both tests were performed in a universal testing machine (EMIC 2000) recording the fracture load (N). Strength values (MPa) were calculated and statistically analyzed by ANOVA and Tukey (a = 0.05). The mean and standard deviation values (MPa) were Z250-45.06 ± 5.7; AM-35.61 ± 5.4; VE-34.45 ± 7.8; and EX-42.87 ± 6.6 for st; and Z250-126.52 ± 3.3; AM-87.75 ± 3.8; VE-104.66 ± 4.4; and EX-119.48 ± 2.1 for sf. EX and Z250 showed higher st and sf values than the other materials evaluated (p < 0.05), which followed a decreasing trend of mean values. The results confirmed the study hypothesis, showing a positive relation between the material properties examined.

Avaliação da microdureza superficial do esmalte e da dentina de dentes bovinos e humanos (permanentes e decíduos) / Surface microhardness evaluation of enamel and dentin in bovine and human teeth (permanent and deciduous)

O objetivo desse estudo foi testar a microdureza superficial do esmalte (E) e da dentina (D) em molares humanos decíduos (grupo d), molares humanos permanentes (grupo p) e incisivos bovinos (grupo b). Foram selecionados 4 espécimes de cada tipo de dente os quais foram mantidos em solução salina até o teste. Os espécimes foram incluídos em uma matriz com resina e polidos com papel metalográfico (até granulação 600) para planificar o esmalte. O teste de dureza Knoop foi realizado em um microdurômetro com carga de 200 g, sendo realizadas 5 leituras (10 s de endentação) por dente. Os espécimes foram novamente submetidos ao polimento para expor dentina (próxima ao LAD), sendo novas leituras realizadas. Os dados foram submetidos à análise estatística (testes ANOVA e Tukey). Os valores médios de dureza (kg/mm2) e desvio padrão foram os seguintes: Ed 338 ± 30,1; Ep 341 ± 32,8; Eb 326 ± 25,5; Dd 104 ± 9,7; Dp 93,3 ± 8,7; Db 91,2 ± 7,3. A dureza do esmalte foi maior que a da dentina nos três tipos de dentes (p < 0,001). Considerando o tipo de substrato, não houve diferenças estatísticas, ou seja, os valores de dureza para esmalte ou dentina foram similares para dentes humanos decíduos e permanentes e dentes bovinos.

The objective of this study was to evaluate the surface microhardness of enamel (E) and dentin (D) from human deciduous molar teeth (Group d), human permanent molar teeth (Group p) and bovine incisor teeth (Group b). Four specimens were selected for each group and stored in saline solution until testing. The specimens were embedded into a resin matrix and polished to 600 grit SiC paper creating a flat enamel surface. The Knoop hardness test was performed in a microhardness device, using a 200 g load. Five measurements were made in each specimen. After that, specimens were polished to expose dentin (near to dentinenamel junction), and other five microhardness measurements were performed per specimen. The values were calculated and statistically analyzed (ANOVA and Tukey tests). Mean hardness values (kg/mm2) and standard deviations were as follows: Ed 338 ± 30.1; Ep 341 ± 32.8; Eb 326 ± 25.5; Dd 104 ± 9.7; Dp 93.3 ± 8.7; Db 91.2 ± 7.3. The microhardness in enamel (E) was statistically higher than in dentin (D) for the three type of teeth studied (p < 0.001). Considering the type of substrate, there were no statistical differences, meaning that the mean hardness values for either enamel or dentin were not different for the human deciduous teeth, human permanent and bovine teeth.

A influência de diferentes métodos de ampliação cervical na obtenção do comprimento de trabalho em canais mesiovestibulares de primeiros molares superiores / The influence of different methods of cervical magnifying in the attainment of the lenght of work in first mesio-vestibular canals tests of superior molar

A ampliação da entrada de canais radiculares com o uso de diferentes tipos de métodos e instrumentos é alvo de inúmeras pesquisas na Odontologia. O objetivo deste estudo foi determinar a influência de quatro sistemas distintos de instrumentos rotatórios para alargamento cervical na determinação do comprimento real de trabalho (CRT). Por meio da comparação entre esses quatro tipo de instrumento diferentes que podem ser utilizados pelo profissional, averiguou-se o mais efetivo para a ampliação cervical de canais radiculares curvos. A etapa experimental foi realizada no Laboratório de Endodontia da Faculdade de Odontologia da Universidade de Passo Fundo (FOUPF). O estudo in vitro foi feito com 40 raízes mesiovestibulares de primeiros molares superiores humanos permanentes, obtidas no banco de dentes da FOUPF. As 40 amostras foram divididas aleatoriamente em 4 grupos de 10 dentes cada, os quais foram submetidos ao acesso endodôntico convencional. Após a verificação do CRT, aplicaram-se os métodos de ampliação cervical em cada grupo, com uso de brocas Gates-Glidden (Dentsply Maillefer, Ballaigues, Suíça) no grupo 1, alargadores rotatórios de níquel-titânio Orifice Openers (SybronEndo, Glendora, USA) no grupo 2, instrumentos de níquel-titânio SX e o instrumento S1 (ProTaper ­ Dentsply Maillefer, Ballaigues, Suíça) no grupo 3 e LA Axxess (SybronEndo, Glendora, USA) no grupo 4. Na seqüência verificou-se novamente o CRT. A diferença entre a primeira e a segunda odontometria foi calculada (ANOVA), e o teste de comparações múltiplas de Tukey (p ≤ 5%) identificou diferenças significativas entre os grupos avaliados. Os instrumentos rotatórios de níquel-titânio SX e S1 do sistema ProTaper apresentaram os melhores resultados, e os instrumentos rotatórios de aço inox Gates-Glidden (brocas) tiveram os piores resultados

The magnifying of radicular canals using different types of methods and instruments is focus of innumerable researches in Deontology. The objective of this study was to determine the influence of four distinct systems of rotatory instruments for cervical widening in the determination of the real length of work (CRT). Through the comparison among these four types of possible different instruments to be used by the professional it was possible to evaluate the most effective for the cervical magnifying of arched radicular canals. The experimental stage was carried through in the Laboratory of Endodontia of the College of Odontologia of the University of Passo Fundo (FOUPF). The present in vitro study involved 40 roots of first mesio-vestibular tests of molar permanent human superiors, gotten in the Tooth Bank of the College of Odontologia of the University of Passo Fundo (FOUPF). The 40 samples have been divided randomly in 4 groups of 10 teeth each, which have been submitted to the conventional endodontic access. After the verification of the real CRT, the methods of cervical magnifying in each group have been applied, being group 1 with Gates-Glidden drills (Dentsply Maillefer, Ballaigues, Switzerland), group 2 with rotatory nickel-titanium wideners ORIFICE OPENERS (SybronEndo, Glendora, the USA), group 3 with nickel-titanium instruments SX and the S1 instrument (ProTaper - Dentsply Maillefer, Ballaigues, Switzerland), and group 4 with LA Axxess (SybronEndo, Glendora, USA). After that the CRT was verified again. The difference between the first and the second odontometry has been calculated (ANOVA) and the test of multiple comparisons of Tukey (p ≤ 5%) identified significant differences between the studied groups. The rotatory nickel-titanium instrument SX and S1 of the ProTaper system has presented the best results and the rotatory steel instruments inox Gates Glidden (drills) have presented the worst ones

Microbial leakage and apical inflammatory response in dog's teeth after root canal filling with different sealers, post space preparation and exposure to the oral environment

Coronal leakage is an important factor affecting the outcome of endodontic therapy. This study evaluated the microbial leakage (ML) and the apical inflammatory response (AIR) in dog's teeth after root canal filling with three endodontic sealers, post preparation and exposure to the oral environment, testing the hypothesis that there is a positive correlation between these two histological parameters (ML and AIR). Sixty-four root canals of 8 mongrel dogs were cleaned, shaped and randomly distributed into groups according to the sealer to be used: Sealer 26 (n=18); AH Plus (n=18); RoekoSeal (n=19); no sealer - control group (n=9). Root canals were filled by the lateral condensation technique. Post space preparation left 4 mm of filling material in the apical root third, and specimens were exposed to the oral environment for 90 days. The dogs were killed and jaw blocks were histologically processed using Brown & Brenn and HE staining techniques. ML and AIR were scored from 1 to 4. Results were analyzed statistically using ANOVA, Duncan's post-hoc test and Spearman's correlation. ML and AIR score means were: Sealer 26 - 2.44±0.98 and 2.50±0.70; AH Plus - 2.50±0.78 and 2.22±0.54; RoekoSeal - 1.84±0.95 and 2.63±0.83; Control - 2.56±1.23 and 3.11±0.60. Statistically significant differences in AIR scores were found between the AH Plus and control groups (p<0.05). Although RoekoSeal had the lowest ML means, and AH Plus, the lowest AIR means after 90-day exposure to the oral environment, no statistically significant differences were found between the three sealers under study, and no correlation was found between ML and AIR.

Influence of shade and irradiation time on the hardness of composite resins

This study tested the following hypotheses: 1. increasing light irradiation time (IT) produces greater values of superficial hardness on different depths (0 and 3 mm); and 2. a dark shade composite (A3) needs longer IT than a light shade composite (A1) to produce similar hardness. Disk-shaped specimens (n=24 per shade) were fabricated using a 3-mm-thick increment of composite resin (Z100). Specimens were randomly assigned to 3 groups (n=8) according to the IT (400 mW/cm2) at the upper (U) surface: A1-10 and A3-10: 10 s; A1-20 and A3-20: 20 s; A1-40 and A3-40: 40 s. Specimens were stored in black lightproof containers at 37ºC for 24 h before indentation in a hardness tester. Three Vickers indentations were performed on the U and lower (L) surfaces of each specimen. The indent diagonals were measured and the hardness value calculated. The results were analyzed statistically by ANOVA and Tukey's test (alpha=0.05). Statistically significant differences were found between U and L surfaces of each composite shade-IT combination (p=0.0001) and among the ITs of same shade-surface combination (p=0.0001), except between groups A1-20U and A1-40U, confirming the study hypothesis 1 and partially rejecting the hypothesis 2.

Esse estudo testou as hipóteses de que: 1. maior tempo de fotopolimerização (TF) produz maior dureza superficial em diferentes profundidades (0 e 3 mm) de resina composta (RC); 2. a cor escura (A3) de RC exige maior TF do que a RC clara (A1) para obter o mesmo grau de D. Foram fabricados 24 corpos-de-prova para cada cor de RC em único incremento de 3 mm (Z100), dividindo-os em 3 grupos (n=8), de acordo com os TF (400 mW/cm²) na superfície superior (S): A1-10 e A3-10: 10 s; A1-20 e A3-20: 20 s; A1-40 e A3-40: 40 s. Os corpos-de-prova foram armazenados sem luz, a 37ºC por 24 h, antes de aferir o grau de dureza nas superfícies S e inferior (I) com um durômetro. Foram realizadas 3 penetrações Vickers em cada superfície (S e I) dos corpos-de-prova (n=24). As diagonais das penetrações foram medidas e os valores de dureza calculados. ANOVA e Tukeyforam usados nas análises estatísticas (a=0,05). Ocorreram diferenças significativas entre S e I para cada combinação de cor-TF (p=0,0001) e entre os TF de mesma combinação cor-superfície (p=0,0001), exceto entre A1S20 e A1S40, confirmando a hipótese 1, mas rejeitando parcialmente a hipótese 2.

Surface roughness of glazed feldspar, alumina, and zirconia-based ceramics

A proposta deste estudo foi comparar a rugosidade superficial de cerâmicas feldspáticas, cerâmicasa base de zircônia e outra de alumina, avaliandoa hipótese que cerâmicas feldspáticas apresentammenor rugosidade superfi cial que cerâmicas de infraestrutura. Oito discos (diâmetro: 5mm; espessura:2mm) de cada cerâmica foram fabricados conformeas recomendações dos fabricantes: V7- cerâmicafeldspática (Vita VM7); VA- cerâmica feldspática (Vitadur-α); IA- cerâmica de alumina infiltrada porvidro (Vita In-Ceram Alumina); IZS- cerâmica dezircônia-alumina infi ltrada por vidro (Vita In-CeramZirconia); IZB- cerâmica de zircônia-alumina infi ltradapor vidro (Vita In-Ceram Zirconia 2000 for CerecInLab). Todos os materiais foram glazeados conformeas recomendações do fabricante. Quatro leituras derugosidade Ra (Mitutoyo SJ 400) por espécime foramfeitas, obtendo a média por espécime (n=8). Os dadosforam analisados pelo teste de ANOVA 1-fator e deTukey. (α=0,05). V7 apresentou a mais baixa médiade rugosidade (0,43±0,07 µm) comparada às outrascerâmicas. Não houve diferença estatística entre osvalores de VA (0,94±0,2 µm), IA (0,7±0,13 µm), IZS (0,98±0,3 µm) e IZB (0,75±0,4 µm). A hipótese foiparcialmente aceita. V7 teve uma superfície mais lisaque VA. Os valores de rugosidade das cerâmicas altamentecristalinas para infra-estrutura (IA, IZS, IZB)não foram diferentes estatisticamente.