Physicochemical properties of three bioceramic cements

Abstract: This study aimed to compare the physicochemical properties of MTA Angelus (MTA-A), MTA Repair HP (MTA-HP), and Biodentine (BD). Setting times (n = 7) were determined in accordance with ASTM C266-15. Solubility (n = 11), pH (n = 10), and calcium ion release (n = 10) were evaluated up to 28 days in accordance with ANSI/ADA specification no. 57. Radiopacity was assessed by ANSI/ADA (n = 10) and the tissue simulator method (n = 10). In both methods, the specimens were radiographed using an aluminum stepwedge and the digital radiographs were analyzed in Adobe Photoshop, determining the mean grayscale pixel values of the materials, of the 3-mm aluminum stepwedge, and of the dentin, the latter of which was analyzed on the tissue simulator. The data obtained from each test were statistically analyzed and compared (p < 0.05). MTA-A presented longer final setting time compared with the other materials. There were no significant differences in the mass values of materials during the experiment. All materials presented an alkaline pH. BD promoted greater calcium ion release in most of the experimental periods. All materials presented appropriate radiopacity. BD showed lower radiopacity than MTA-A in the tissue simulator method. All groups presented higher radiopacity in the tissue simulator when compared with the ANSI/ADA method. MTA-A, MTA-HP, and BD showed appropriate physicochemical properties and radiopacity, and were considered suitable to be used in clinical practice.

XP Endo Finisher-R and PUI as supplementary methods to remove root filling materials from curved canals

Abstract: This study assessed the ability of XP-endo Finisher R (FKG, La Chaux-de-Fonds, Switzerland) to remove filling remnants from curved mesiobuccal canals of maxillary molars, using the passive ultrasonic irrigation (PUI) technique as a comparison. Twenty-four curved main mesiobuccal canals (MB1) of maxillary molars were instrumented with Wave One (#25/07) and filled with gutta-percha points and AH Plus Sealer. Samples were then re-treated with a standardized protocol with Wave One (#35/06) as the master apical file. Micro-CT scans measured baseline volume of remaining filling material (in mm3). Samples were divided into two groups (n = 12) according to the supplementary cleaning approach: (PUI) or XP-endo Finisher R. Statistics compared baseline and final volume of filling material (within-group); and the percentage of filling material reduction (between-group). Mean baseline volumes, final volumes, and percentages of reduction (%) of filling material for XP-endo Finisher R and PUI were respectively: 0.060 mm3, 0.042 mm3, and 31.28%; and 0.064 mm3, 0.054 mm3, and 16.57%. Both tested protocols reduced the amount of filling material (p < 0.05). XP-endo Finisher R had higher percentage of reduction as compared to PUI (p < 0.05). XP-endo Finisher R and PUI used as supplementary cleaning protocols during re-treatment improved the removal of root filling material in curved canals; but XP-endo Finisher R was approximately twice more efficient. The complete filling material removal during re-treatment procedures is still a challenge. Supplementary cleaning protocols may help to remove the remaining material after the complete mechanical preparation of curved canals. XP-endo Finisher R was approximately twice more efficient than PUI.

The effectiveness of rotary and reciprocating techniques in curved root canals retreatment: a micro- CT analysis

Introduction: Different NiTi rotary systems have been developed to improve efficiency and retreatment success rates. Aim: To evaluate the Protaper Universal retreatment system and WaveOne instrument in removing the filling material from curved canals during retreatment. Materials and Methods: Thirty mesial root canals of extracted human mandibular molar teeth were randomly allocated into 2 groups (n=15). In the PT group, retreatment was performed with ProTaper Universal Retreatment according to the manufacturer's instructions. In the WO group, was used WaveOne Primary. ProTaper Universal F2 and F3 were used to achieve the apical diameter in both groups. The samples were scanned by micro-computed tomography pre and postoperatively to evaluate the filling material remaining. The percentage of material filling was compared between groups using Student's T test and in the same group among thirds was compared using Kruskal-Wallis followed by Dunn's post hoc test. Results: The filling material remaining was not statistically different between the groups (p≥0.05). The apical third presented a greater amount of remaining filling material when compared with the cervical third for both groups (p<0.05). Conclusion: Rotary and reciprocating techniques can effectively, but not completely, remove the filling materials from the root canal system. The apical third presented a more significant amount of remaining filling material.

The unplanned and unequal expansion of Dentistry courses in Brazil from 1856 to 2020

Abstract: This study analyzed the consequences of the disordered expansion of Dentistry courses on the distribution of professionals, the job market, and limitations of the National System of Higher Education Assessment (SINAES) developed as a guarantee of education quality. This observational, descriptive, and analytical study used secondary data from several official databases. The number of courses was obtained from the e-MEC registry. From the Higher Education Census, the study collected historical series of courses offered, number of candidates per open seat, number of individuals who initiated and completed the course, and information about professors in the public and private schools. The reports related to Dentistry courses from the National Health Council were also analyzed. The performance of undergraduate students was assessed from synthesis reports of Enade from 2004 to 2016. The number of dentists and their regional distribution was based on the Federal Dental Council, and Brazilian population and gross domestic product were collected from the Brazilian Institute of Geography and Statistics. Dentistry courses in Brazil grew exponentially from 1856 to 2020; among the 544 authorized courses, 82 currently have not yet started their activities. The fast expansion of courses in Brazil has worsened the regional asymmetries in the supply of dentist, and the SINAES has not been able to fully assure the quality of Dentistry courses. Brazilian dentistry, which has increased its scientific and technological development since the 19th century, with outstanding intellectual production, is at risk of a collapse due to a plethora of dentists.

Estimativa da idade com finalidade pericial em imagens axiais das duas primeiras vértebras cervicais ­ estudo piloto / Age estimation for forensic purposes in axial images of the two first cervical vertebrae ­ a pilot study

Introdução: A determinação do desenvolvimento esquelético é uma prática comum ao exercício da Odontologia, tanto para fins ortodônticos quanto forenses. Diversos métodos utilizam radiografias e, tendo em vista o crescente emprego da tomografia computadorizada, torna-se importante o conhecimento de todas as potencialidades destas imagens na prática pericial. Objetivo: O objetivo deste estudo foi descrever parâmetros morfológicos das vértebras cervicais C1 e C2 em imagens axiais de tomografia computadorizada por feixe cônico (TCFC) em cada um dos seis estágios maturacionais propostos por Hassel e Farman (1995) para a análise das vértebras no plano sagital. Material e Método: A partir de um banco de dados, foram avaliadas imagens de TCFC de 73 indivíduos de 8 a 18 anos, as quais foram classificadas no plano sagital. Em seguida, as vértebras C1 e C2 foram avaliadas no plano axial e suas características morfológicas registradas em um instrumento de coleta de dados. Foram, então, calculados os percentuais de cada característica dentro dos estágios maturacionais. Resultados: Observou-se na caracterização morfológica axial da C2 a tendência de fusionamento da sincondrose subdental nas fases de Maturação (5) e Finalização (6), ocorrendo em 90% e 66,6% dos casos, respectivamente. Conclusão: O estudo identificou padrões morfológicos axiais da C2 predominantes nas fases 5 e 6 de maturação das vértebras cervicais propostas por Hassel e Farman (1995), podendo contribuir para casos forenses de estimativa da idade.

Introduction: The skeletal development determination is a common practice in Dentistry, both for orthodontic and for forensic purposes. Several methods are based on radiographs, but considering the increase in computed tomography exams more contemporary investigations of these methods became important to explore their forensic purposes. Objective: This study aimed to describe the morphological parameters of the C1 and C2 vertebrae in axial cone beam computed tomography (CBCT) images, at each of the six maturational stages proposed by Hassel and Farman. Material and Method: From a database, CBCT images of 73 individuals aged 8 to 18 years were evaluated and classified in the sagittal plane. Then the C1 and C2 vertebrae were evaluated in the axial plane and their morphological characteristics were recorded in a data collection instrument. The percentage of each feature within the maturational stages was calculated. Results: In the axial morphological characterization of C2, the tendency of fusion of the subdental was marked in Maturation (5) and Finishing (6) phases, with 90% and 66.6% of cases, respectively. Conclusion: The study identified axial morphological patterns of C2 that predominate in phases 5 and 6 of maturation of the cervical vertebrae proposed by Hassel and Farman, and may contribute to age estimation in forensic cases.

Radiopacity Evaluation of Gutta-Percha Points in Thinner Samples than the ANSI/ADA Recommendation

Abstract The aim of this study was to evaluate the radiopacity of different gutta-percha points (Endo Points®, Dentsply®, Tanari®, Meta®, Roeko® and Odous®) in samples of 1 mm thick as established by ANSI/ADA Specification #57 and ISO 6876/2001, in comparison with thinner samples. Twelve test specimens for each material, four for each thickness (0.3, 0.6, and 1 mm and diameter of 8 mm), were laminated and compressed between two polished glass plates until the desirable thickness. Digital radiographs were obtained along with a graduated aluminum stepwedge varying from 1 to 10 mm in thickness. The X-ray unit was set at 70 kVp, 10 mA and 0.4 s exposure time, at a focal distance of 36 cm. One calibrated observer quantified the average values of pixels with Adobe Photoshop® software. Data were analyzed using ANOVA and Tukey tests, at 5% significance level. At 0.6 and 1 mm thickness, all the tested materials showed radiopacity higher than 3 mm of aluminum (reference value). At 0.3 mm thickness, Odous and Tanari presented significantly less radiopacity than the reference, and the other materials showed similar radiopacity to the reference. The study concluded that the materials demonstrated different radiopacities and all had values above the minimum recommended by ANSI/ADA specification #57, being Odous and Tanari less radiopaque than the reference value in thinner samples (0.3mm).

Resumo O objetivo deste estudo foi avaliar a radipacidade de diferentes pontas de guta-percha (Endo Points®, Dentsply®, Tanari®, Meta®, Roeko® e Odous®) em amostras de 1 mm de espessura, conforme estabelecido pela especificação #57 da ANSI/ADA e pela ISO 6876/2001, em comparação com amostras de menor espessura. Doze amostras de cada material, quatro para cada espessura (0,3, 0,6 e 1 mm; 8 mm de diâmetro), foram confeccionadas por meio de laminação e compressão entre duas lâminas de vidro polidas, até a espessura desejada. Radiografias digitais foram obtidas juntamente com uma escala de alumínio graduada, com espessuras variando de 1 a 10 mm. O aparelho de raios X foi ajustado para 70 kVp, 10 mA, 0,4s de tempo de exposição, com distância focal de 36 cm. Um observador calibrado quantificou a média dos valores de pixel no programa Adobe Photoshop®. Os dados foram analisados utilizando os testes ANOVA e Tukey, com nível de significância de 5%. Nas espessuras de 0,6 e 1 mm, todos os materiais testados apresentaram radiopacidade maior do que 3 mm de alumínio (valor de referência). Na espessura de 0,3 mm, Odous e Tanari apresentaram radiopacidade significativamente menor que a referência, e as outras marcas mostraram radiopacidade semelhante à referência. Conclui-se que os materiais apresentaram diferentes radiopacidades e todos mostraram valores acima do mínimo recomendado pela especificação #57 da ANSI/ADA, sendo Odous e Tanari menos radiopacos do que o valor de referência nas amostras mais finas (0.3 mm).

Oral manifestations in pediatric patients receiving chemotherapy for leukemia / Manifestações bucais em pacientes pediátricos submetidos a quimioterapia para leucemia

Cross-sectional study of 36 children with acute lymphoblastic leukemia (ALL) or acute myeloid leukemia (AML). Intraoral examination and oral hygiene assessment were performed in all patients. Information was also obtained from interviews of patients' mothers and a review of medical records. Results: The sample was largely composed of boys (58.3%), ages 5­9 years. The most commonly used chemotherapy regimen was the BFM-95 protocol. Most children (83.3%) had a record of some oral manifestation during treatment. On intraoral examination, 17 children (50%) were found to have at least one oral manifestation. The most frequent manifestation was also mucositis (26.5%), followed by gingival bleeding (23.4%). Lower maternal educational level was associated with increased frequency of mucositis, as were induction chemotherapy and maintenance chemotherapy after relapse. Conclusions: Oral abnormalities were common in children receiving chemotherapy and mucositis was the most prevalent manifestation. Oral lesions were associated with the induction phase of chemotherapy. Mucositis was not associated with oral health status.

Estudo transversal de 36 crianças com leucemia linfoblástica aguda (LLA) ou leucemia mieloide aguda (LMA). Exame intraoral e avaliação de higiene bucal foram realizados em todos os pacientes. A informação também foi obtida a partir de entrevistas com as mães dos pacientes e uma revisão dos registros médicos. Resultados: A amostra foi composta em grande parte dos meninos (58,3%), com idades entre 5-9 anos. O regime de quimioterapia mais comumente utilizado foi o protocolo BFM-95. A maioria das crianças (83,3%) teve um registro de alguma manifestação oral durante o tratamento. Ao exame intraoral, 17 crianças (50%) apresentaram ter pelo menos uma manifestação oral. A manifestação mais frequente foi mucosite (26,5%), seguido por sangramento gengival (23,4%). Baixa escolaridade materna foi associada com aumento da frequência de mucosite, assim como a quimioterapia de indução e quimioterapia de manutenção após recaída. Conclusões: Anormalidades orais são comuns em crianças que receberam quimioterapia e mucosite foi a manifestação mais prevalente. As lesões foram associados com a fase de indução da quimioterapia. Mucosite não foi associado com o estado de saúde oral.

Influência da conicidade dos instrumentos rotatórios de NiTi no transporte apical û um estudo comparativo com tomografia computadorizada / Influence of taper of NiTi rotary instruments in apical transportation: a comparative study with computed tomography

A proposta deste estudo foi avaliar, ex vivo, a influência da conicidade dos instrumentos rotatórios de níquel-titânio (NiTi) no transporte apical de canais radiculares curvos com tomografia computadorizada. Vinte primeiros molares superiores humanos extraídos foram selecionados e divididos em dois grupos. Os canais radiculares no GrupoHERO 642 (n=10) foram preparados com instrumentos rotatórios de NiTi do sistema HERO 642, conicidade 0,02. Os canais radiculares do Grupo EASY ProDesign (n=10) foram preparados com instrumentos rotatórios de NiTi EASY ProDesign, conicidades múltiplas. O transporte apical foi mensurado comparando imagens de tomografia computadorizada antes do preparo, após o preparo com instrumentos # 35/.02 (Grupo HERO 642) e instrumento # 35/.04 (Grupo EASY ProDesign), e após o preparo com instrumento # 45/.02 (Grupo HERO 642) e instrumento # 40/.04 (Grupo EASY ProDesign). Os dados foram analisados utilizando ANOVA e o nível de significância p. 05. Os valores médios de transporte apical em milímetros (mm) para o Grupo HERO 642 foram 0,93 ± 0,48 mm (#35/.02) e 1,48 ± 0,63 mm (# 45/.02) e para o Grupo EASY ProDesign foram 0,82 ± 0,85 mm (# 35/.04) e 1,03 ± 0,92 mm (# 40/.04). Os instrumentos rotatórios de NiTi de conicidade 0,02 e de múltiplas conicidades mostraram desempenho similar em relação ao transporte apical em canais radiculares curvos.

The aim of this study was to evaluate ex vivo the influence of the taper of nickel-titanium (NiTi) rotary instruments in apical transportation of curved root canals with computed tomography. Twenty extracted maxillary first molars were selected and divided into two groups. The mesiobuccal root canals in Group HERO 642 (n=10) were instrumented with HERO 642 rotary instruments, 0.02 taper. The mesiobuccal root canals in Group EASY ProDesing (n=10) were instrumented with EASY ProDesign rotary instruments, multiple tapers. Apical transportation was measured by comparing tomographic images before preparation, after the preparation with size 35, 0.02 taper (Group HERO 642) and size 35, 0.04 taper (Group EASY ProDesing), after the preparation with size 45, 0.02 taper (Group HERO 642) and size 40, 0.04 (Group EASY ProDesing). Data were analyzed using ANOVA, and significance was set at p.05. The preparation of curved root canals can be accomplished with instruments of diameters and taper larger than 0.02.

Oral health policy of the city of Porto Alegre, southern Brazil: Analysis of the database of the Outpatient Information System of the Brazilian Unifi ed Health System / Política de saúde bucal do Município de Porto Alegre: Análise do banco de dados do Sistema de Informações Ambulatoriais do SUS

Specifi cally for the dentistry fi eld, the pact for health expresses the relevance of the process of evaluation and monitoring of primary care programs and services. The aim of the present study was to analyze the oral health poli cy of the city of Porto Alegre, Southern Brazil, in the context of the decentralization in health care implemented by the Brazilian Unifi ed Health System (Sis tema Único de Saúde, SUS), based on the database of the Outpatient Information System (Sistema de Informações Ambulatoriais, SIA). This descriptive, quantitative, normative/evaluative study analyzed secondary data from a historical series of dental procedures conducted in Porto Alegre and recorded by the SIA-SUS from 2008 to 2012. Data were collected directly from the SIA-SUS database. Data were also obtained from city's management reports from 2010 to 2013. Results show that the coverage of both Programmatic First Dental Consultation and Collective Supervised Toothbrushing Action was lower than that established in the pact.

Especifi camente para o campo da odontologia, o pacto pela saúde expressa a relevância no processo de avaliação e monitoramento de programas e serviços da atenção básica. O objetivo do presente estudo foi analisar a políti ca de saúde bucal do município de Porto Alegre no contexto da descentralização da saúde implementada pelo Sis tema Único de Saúde (SUS), a partir do banco de dados do Sistema de Informações Ambulatoriais (SIA). Este estudo foi do tipo descritivo, quantitativo, de caráter avaliativo normativo, o qual utilizou dados secundários, a partir da série histórica da produção de procedimentos odontológicos realizados em Porto Alegre e registrados pelo SIA-SUS no período de 2008 a 2012. A coleta dos dados foi realizada diretamente no banco de dados do SIA-SUS. Dados também foram retirados dos relatórios de gestão do município nos anos de 2010 a 2013. Os resultados demonstram que tanto a cobertura da Primeira Consulta Odontológica Programática quanto a Ação Coletiva de Escovação Dental Supervisionada foram inferiores ao pactuado.

Avaliação longitudinal das alterações transversais após expansão rápida cirurgicamente assistida da maxila / Longitudinal evaluation of the transverse changes after surgically assisted rapid expansion of the maxilla

Foram analisadas as alterações transversais após expansão rápida cirurgicamente assistida da maxila (ER-CAM) em uma amostra de 37 pacientes adultos com deficiência maxilar esquelética transversal, tratados com o aparelho expansor de Haas e a técnica cirúrgica proposta por Bell2 (1976). Foram comparadas as medidas lineares inter-caninos e inter-primeiros molares superiores nos modelos da documentação ortodôntica inicial, ao final da expansão rápida da maxila e um ano após esta. A ANOVA utilizando o delineamento de medidas repetidas, complementada pelo teste de comparações múltiplas de Tukey (a = 1%), evidenciou diferenças significativas nos três momentos para as duas medidas propostas. Os resultados obtidos no presente estudo permitem concluir que as medidas de dimensões transversais da maxila aumentam ao final da expansão, mais na região anterior que na posterior; diminuem após transcorrido um ano do final da expansão, mais na região anterior que na posterior; e a recidiva observada após o período de um ano não supera o ganho obtido com a expansão, tanto na região anterior quanto na posterior.

Transverse changes after surgically assisted expansion of the maxilla were assessed in a group of thirty-seven adult patients with transversal skeletal deficiency, which used Haas device and were submitted to Bell2 (1976) surgical procedure. Transversal measurements between upper canines and first molars were obtained before treatment, immediately after expansion and after one year. The ANOVA for repeated measures and Tukey’s multiple comparison Test (a = 1%) showed significant differences among the three moments for both measurements proposed. The results lead to the conclusion that the transverse dimensions increase more in the anterior region of the maxilla at the end of the expansion, decrease after one year more in the anterior region, and that the relapse does not exceeds the gain in both regions.

Analysis of remaining tissue after using LA AXXESS® drill in flaring of cervical mesial canals of mandibular molars

Introduction and Objective: The objective of this study was to analyze, in vitro, the remaining tissue at the risk zone in the mesial canals of the mandibular molars after cervical flaring using LA AXXESS® drill. Material and methods: Thirty molars were randomly divided into two experimental groups. Twenty teeth received cervical flaring using LA AXXESS® drill (group A), and ten were kept as control group (group B) without undergoing any kind of flaring. The teeth had their mesial roots cross-sectioned at a 3.5 mm standardized height apical to the cementum junction. Specimens were scanned and analyzed by a professional previously trained and calibrated. In order to measure the distances of the remaining tissue in relation to the furca, a Photoshop® program ruler version 7.0 was used. Results and Conclusion: It was possible, through statistical analysis using Student's t-test for paired and independent samples with a 5% significance level, to verify that there was no difference regarding the remaining tissue at the risk zone between the group that had cervical flaring and the control group.

Evaluation of optical density of bone defects filled with calcium phosphate cement and bioactive glass in rats / Avaliação da densidade óptica de cavidades ósseas preenchidas com cimento de fosfato de cálcio e vidro bioativo em ratos

Purpose: To evaluate new bone formation, by the analysis of optical density, in rat femoral defects filled with calcium phosphate cement (CPC) and bioactive glass (BG). Methods: Twenty-one rats were divided into three groups, Group I (CPC), Group II (BG), and Group III (control), and assessed after 7, 15, and 30 days. Three bone cavities were made in the left femur and filled with CPC, BG, and no material (control). Digital images were obtained and the results were subjected to statistical analysis of variance (ANOVA), complemented by the Friedman and Kruskal-Wallis nonparametric tests, with a significance level of 5 percent. Results: Regarding optical density, Group I showed statistical values significantly higher than Group III and also higher, although not statistically significant, than Group II, in all observation periods. When Groups II and III were compared, Group II showed higher optical density values, without statistically significant differences, in all periods. Conclusion: The biomaterials analyzed showed higher optical density in relation to the control group in all observation periods, calcium phosphate cement being the best option in the repair of bone defects, but without statistically significant differences in relation to bioactive glass.

Objetivo: Avaliar a neoformação óssea, por meio da análise de densidade óptica, em cavidades em ratos preenchidas com cimento de fosfato de cálcio (CFC) e vidro bioativo (VB). Métodos: Utilizou-se 21 ratos distribuídos em três grupos, sendo Grupo I (CFC), Grupo II (VB) e Grupo III (controle) avaliados em 07, 15 e 30 dias. Foram realizadas três cavidades, junto ao fêmur esquerdo e preenchidas com CFC, VB e sem material (controle). Realizaram-se radiografias digitais e os resultados foram submetidos à análise estatística de variância (ANOVA), complementada através dos testes não-paramétricos de Friedman e Kruskal-Wallis, com níveis de significância de 5 por cento. Resultados: Comparando a densidade óptica o Grupo I apresentou valores estatísticos significativamente maiores que o Grupo III, e também apresenta valores maiores, sem diferença estatística significativa, em todos os períodos, quando comparado ao Grupo II. Quando comparamos o Grupo II com o Grupo III, o Grupo II apresenta valores maiores de densidade óptica, sem diferença estatística significativa, em todos os períodos. Conclusão: Observou-se maior densidade óptica dos biomateriais em relação ao grupo controle em todos os períodos avaliados, sendo o cimento de fosfato de cálcio a melhor opção para restauração de cavidades ósseas, porém sem diferenças estatisticamente significantes em relação ao vidro bioativo.

CT evaluation of apical canal transportation associated with stainless steel hand files, oscillatory technique and ProTaper rotary system

This study used computed tomography (CT) to compare apical canal transportation in mesiobuccal canals of maxillary molars prepared with different techniques. Sixty teeth were assigned to 3 groups (n=20), according to the technique used for root canal instrumentation: hand instrumentation with K-Flexofiles, K-Flexofiles activated by an oscillatory system and ProTaper NiTi rotary system. Pre and post-instrumentation CT images were obtained 3 mm short of the apical foramen and were superimposed to compare canal transportation. Data were analyzed statistically by ANOVA and Tukey's test using the SPSS software (α=0.05). In the buccal direction, the manual technique produced significantly less canal transportation than the oscillatory technique (p<0.05) and both were similar to the rotary technique (p>0.05). In the distal and distopalatal directions, the oscillatory technique produced more canal transportation (p<0.05). In the mesiopalatal direction, the oscillatory technique produced more canal transportation than the manual technique (p<0.05), and both were similar to the rotary technique (p>0.05). In conclusion, all techniques produced canal transportation, and the oscillatory technique produced the greatest removal of root dentin toward the innerside of the root curvature.

Este estudo utilizou a tomografia computadorizada (TC) para comparar o transporte do canal radicular nos canais mésio-vestibulares de molares superiores preparados por diferentes técnicas. Sessenta molares superiores foram divididos em 3 grupos (n=20) de acordo com a técnica utilizada para o preparo do canal radicular: instrumentação manual com limas K-Flexofile, limas K-Flexofile acopladas a um sistema oscilatório e sistema rotatório ProTaper. Imagens de TC pré e pós-instrumentação foram obtidas 3 mm aquém do forame apical e superpostas para comparar o transporte do canal. Os dados foram analisados estatisticamente pela Análise de Variância (ANOVA) e Teste de Tukey utilizando o software SPSS (α=0,05). Na direção vestibular, a técnica manual produziu significantemente menos transporte do canal radicular do que a técnica oscilatória (p<0,05) e ambas foram similares a técnica rotatória (p>0,05). Nas direções distal e disto-palatina, a técnica oscilatória produziu mais transporte do canal radicular (p<0,05). Na direção mésio-palatina, a técnica oscilatória produziu mais transporte do canal radicular do que a técnica manual (p<0,05), sendo que ambas foram similares à técnica rotatória (p>0,05). Em conclusão, todas as técnicas produziram transporte do canal radicular e a técnica oscilatória produziu os maiores desgastes de dentina na direção interna da curvatura.

The evaluation of higher dental education in Brazil: A cross-sectional study / Avaliação da educação superior de Odontologia no Brasil: um estudo transversal

PURPOSE: In Brazil, the SINAES is a process that is currently used to assess higher education institutions, undergraduate programs and students' performance on the ENADE national exam. This study aimed at assessing the Brazilian undergraduate programs in Dentistry, inquiring if the evaluation results induced to changes to improve the teaching-learning process. METHODS: This cross-sectional study utilized a questionnaire that was e-mailed to 165 professors/coordinators of undergraduate programs in Dentistry in Brazil in 2003/2004. The data analysis was based on the themes of the various open- and closed-ended questions: questions 1, 2, 3 and 4 referred to the evaluation of each institution and its undergraduate program, whereas questions 5, 6 and 7 referred to the ENADE. RESULTS: Changes to improve the quality of teaching in Dentistry and the education of new professionals were driven by the results of the evaluation. These changes were implemented at all institutions that returned the completed questionnaires. CONCLUSION: Improvements in the quality of Brazilian Dentistry will only be possible if the education of the students and the professors is improved.

OBJETIVO: No Brasil, o SINAES é a proposta de avaliação da educação superior atualmente em vigência e que avalia as instituições de educação superior, os cursos de graduação e o desempenho dos estudantes (ENADE). Este estudo abordou a avaliação dos cursos de Odontologia em 2003 e 2004 para observar se os resultados da avaliação induziram melhora no processo ensino-aprendizagem. METODOLOGIA: Este estudo transversal foi realizado por meio de questionários com questões abertas e fechadas enviados por e-mail a 165 professores/coordenadores dos programas de graduação em Odontologia do Brasil em 2003/2004. As questões 1, 2 e 3 se referiram à avaliação das Instituições e dos cursos de Odontologia. As questões 5, 6 e 7 se referiram ao ENADE. RESULTADOS: As mudanças com objetivo de melhora na qualidade do ensino em Odontologia e na educação de novos profissionais são impulsionadas pelos resultados do processo de avaliação. Tais mudanças foram implementadas em todas as Instituições de ensino que retornaram os questionários preenchidos. CONCLUSÃO: Mudanças na qualidade da Odontologia brasileira somente serão possíveis se ocorrer melhora no processo educativo de estudantes e professores.

Effect of endodontic preflaring on electronic determination of working length / Efeito do pré-alargamento endodôntico na determinação eletrônica do comprimento de trabalho

PURPOSE: To evaluate the effect of preflaring on the electronic measurement of working length in mesiobuccal roots of maxillary molars. METHODS: Thirty roots were embedded in an alginate model. Root canals were irrigated with 2.5 percent sodium hypochlorite, and a size 10 K file was inserted into the canal until the locator indicated that apical constriction had been reached. Then, the cervical portion of each canal was flared using the ProTaper system shaping files, whereupon electronic measurements were carried out again. RESULTS: The Student's t test for paired samples did not reveal statistically significant differences in the measurements obtained for preflared and unflared canals (P<0.05). CONCLUSION: Based on the lack of clinical significant relevance of the comparisons carried out in the present study, it is possible to conclude that electronic working length measurement can be carried out either before or after cervical preparation.

OBJETIVO: Avaliar o efeito do pré-alargamento sobre a medição eletrônica do comprimento de trabalho em raízes mésio-vestibulares de molares superiores. METODOLOGIA: Trinta raízes foram incluídas em um modelo de alginato. Canais radiculares foram irrigados com hipoclorito de sódio a 2,5 por cento, e uma lima de tamanho 10 K foi inserida no canal até onde o localizador indicou que a constrição apical tinha sido alcançada. A porção cervical de cada canal foi alargada usando as limas do sistema ProTaper, quando então as medições eletrônicas foram realizados novamente. RESULTADOS: O teste t de Student para amostras pareadas não mostrou diferenças estatisticamente significativas nas medições obtidas para canais pré-alargados e não alargados (P<0,05). CONCLUSÃO: Com base na falta de relevância clínica significativa das comparações realizadas no presente estudo, é possível concluir que a medição do comprimento eletrônico de trabalho pode ser realizado antes ou após o preparo cervical.

Comparison of different methods involved in the planning of clinical crown lengthening surgery

There is little material in the literature that compares biological width measurements in periapical and bite-wings radiographs with clinical measurements. The purpose of this study was to compare measurements of biological width taken by three different methods which are frequently used for planning periodontal surgery - periapical radiograph, bite-wing radiograph and transperiodontal probing - with the trans-surgical measurements. Thirty-four sites from twenty-one subjects were analyzed. The intra-class correlation coefficients between measurements obtained trans-surgically (gold standard) and those obtained by transperiodontal probing, periapical radiography and bite-wing radiography were determined. Average measurements were compared using the Wilcoxon test at a significance level of 0.05. Also, the frequency distribution of differences between test measurements and the gold standard was calculated. The results showed that transperiodontal probing (mean 2.05 mm) was the most accurate measurement, as compared to the gold standard (mean 1.97 mm), with no statistically significant difference observed. On the other hand, periapical and bite-wing radiographic mean values (1.56 mm and 1.72 mm, respectively) were smaller than the gold standard, with statistically significant differences (p < 0.05). It was concluded that transperiodontal probing was the most accurate measurement, as compared to the gold standard, followed by that obtained with the bite-wing radiograph. The clinical relevance of these results could be that planning for crown lengthening surgery should, preferably, include transperiodontal probing.

Produção científica da ULBRA: análise do número e do delineamento das pesquisas publicadas nos suplementos da Brazilian Oral Research (SBPqO) / ULBRA scientific production analysis of the number and the design of research published in the Brazilian Oral Research supplements (SBPqO)

A reunião anual da Sociedade Brasileira de Pesquisa Odontológica (SBPqO) é um evento representativo para a divulgação das pesquisas cientificas na área de odontologia realizadas no Brasil. O objetivo do presente trabalho foi realizar o levantamento das publicações realizadas pelo corpo docente e discente do Curso de Odontologia da Universidade Luterana do Brasil/ULBRA (Campus Canoas, Cachoeira do Sul e Torres) nos Suplementos da Brazilian Oral Research, periódico científico oriundo das apresentações dos painéis na SBPqO. Para isso, os resumos publicados foram acessados por meio de consulta on line no site da instituição e catalogados conforme o ano da reunião, o código da pesquisa, os autores (por sobrenome), a categoria do painel e o delineamento do estudo. Os dados foram transferidos para uma tabela a partir da primeira publicação e analisados em relação ao número de publicações/ano e quanto ao delineamento do estudo. O ano de 2006 apresentou o maior número de publicações (50), entretanto a produtividade apresenta-se em declínio nos últimos três anos (2007, 2008 e 2009). O delineamento da maioria das pesquisas no período analisado são laboratoriais (in vitro) e transversais, ou seja, estudos com baixo poder de gerar evidência científica.

The Brazilian Society for Dental Research (SBPqO) is an annual meeting for the publishing of the dentistry scientific research in Brazil. The aim of this study was to search publications by students and professors of School of Dentistry, Lutheran University of Brazil / ULBRA (Canoas, Cachoeira do Sul, Torres) in the Brazilian Oral Supplements Research, a scientific journal dedicated to publication of SBPqO research banners. Published abstracts were accessed by online searching on site of SBPqO and organized according to: year, code research, authors (surname), banner category and the study design. Data were organized in a table from the first publication and analyzed in relation to the frequency of publications per year and study design. In 2006 there was the highest number of publications (50). However, the publications are decreasing on last three years (2007, 2008 e 2009). The design of most publications at period was in vitro and cross-sectional. These studies have low capacity to generate scientific evidence.

Avaliação da densidade óptica de três resinas compostas fotopolimerizáveis associadas à estrutura dental / Evaluation of tree composites optical density associated to dental structure

O objetivo deste estudo foi avaliar a densidade óptica de três resinas compostas fotopolimerizáveis com diferentes espessuras associadas à estrutura dental, através de programas para análise de radiografias digitalizadas. Utilizou-se um pré-molar humano superior extraído, seccionado no sentido mésio-distal. Foram confeccionados corpos de prova nas espessuras de 1, 2, 3 e 4 mm de cada material restaurador. De cada corpo de prova foram obtidas três radiografias periapicais padronizadas. As imagens foram digitalizadas e, por meio dos programas ImageLab v. 2.3, ImageTool v. 3.0 e Adobe Photoshop v. 6.0, foram obtidos os valores médios e os desvios padrão dos níveis de cinza em uma área padronizada do corpo de prova e da dentina do mesmo dente. A Análise de Variância Múltipla demonstrou não haver diferenças significativas na densidade óptica média tanto das resinas quanto da dentina em relação aos diferentes programas. O Teste de Comparações Múltiplas de Tukey demonstrou que, para todas as espessuras e resinas, a densidade média foi significativamente maior do que a da dentina e que nas resinas testadas a densidade óptica média, apesar de aumentar conforme a espessura do corpo de prova, não difere significativamente em relação à mesma. Diferenças estatisticamente significativas foram observadas entre os três materiais restauradores testados, independente da espessura do corpo de prova. A ordem crescente de densidade óptica encontrada foi: Durafill, Charisma e Z-250.

The aim of this study was to evaluate the optical density of three composites with different thicknesses, associated to the dental structure, through softwares for analysis digitized radiographies. For this, an human upper premolar, sectioned in the mésio-distal. Samples of 1, 2, 3, and 4 mm of thicknesses had been confectioned of each filling material. Of each sample three standardized periapical radiographies had been gotten. The images had been digitized and the average gray levels were obtained through the softwares ImageLab v. 2,3, ImageTool v. 3,0 and Adobe Photoshop v. 6,0., in a standardized area of the sample and the dentin of the same tooth. The Analysis of Multiple Variance, using the delineation block-type, found no significant differences in the average optical density neither for composites nor for dentin in relation to the different softwares. Complementing the analysis with the Test of Multiple Comparisons of Tukey, it is verified that, for all the thicknesses and composites, the mean density - or either the radiopacity - of the composite are significantly higher than the dentine. In all tested materials, the average optical density, although to increase as the thickness of the sample, does not differ significantly. Statistical significant differences had been observed between the three filling materials tested, independent of the thickness of the sample. The increasing order of optical density was: Durafill, Charisma, and Z-250.

Influence of the composition of an experimental adhesive on conversion kinetics, flexural strength and radiodensity / Influência da composição de um adesivo experimental na cinética de conversão, resistência à flexão e radiodensidade

Purpose: To evaluate the effect of the addition of three radiopaque agents to an experimental adhesive on conversion kinetics, flexural strength and radiodensity. Methods: The model adhesive was formulated by mixing 50 wt% Bis-GMA, 25 wt% TEGDMA and 25 wt% HEMA. Barium sulfate, Titanium dioxide and Zirconium in 0.1, 0.2, 0.4, 0.8 and 1.6 wt% were added separately resulting in 15 experimental groups and 1 control group. The conversion kinetics of the model adhesive was evaluated using real time Fourier Transform Infrared Spectroscopy. The flexural tests were performed on 5 specimens (12 × 2 × 2 mm) for each group (total n = 80) in a universal testing machine. The radiodensity was evaluated by using an aluminum step-wedge and VistaScan phosphorous plates radiographs digital system with 0.6 s exposure and focal distance of 40 cm. Results: No statistical difference (P > 0.05) was found in flexural strength among all groups. The values of degree of conversion ranged from 45.51% e 62.46%. All groups showed higher values than 0.54 mm of aluminum for the evaluation of radiopacity. Conclusion: The addition of radiopaquing agents increased the adhesive radiodensity and did not affect its degree of conversion and flexural strength.

Objetivo: Avaliar a influência da adição de três substâncias radiopacificadoras na cinética de conversão, resistência à flexão e radiodensidade de um adesivo experimental. Metodologia: O adesivo foi formulado com 50% de Bis-GMA, 25% TEGDMA e 25% HEMA, em peso. Foram adicionados 0,1%; 0,2%; 0,4%; 0,8%; 1,6%, em peso, de Sulfato de Bário, Óxido de Titânio e Dióxido de Zircônia, totalizando 15 grupos experimentais e um grupo controle. A cinética de polimerização foi avaliada por FTIR em tempo real. O ensaio de miniflexão foi realizado com 5 espécimes (12 × 2 × 2 mm) para cada grupo (n total = 80) em uma máquina de ensaios universal. A radiodensidade foi obtida utilizando um sistema digital com placas de fósforo VistaScan, 0,6 s de exposição e distância focal de 40 cm e os valores foram comparados a uma escala de alumínio. Resultados: Não houve diferença estatisticamente significativa no ensaio de miniflexão entre os grupos (P > 0,05). Os valores de grau de conversão ficaram entre 45,51% e 62,46%, enquanto a radiodensidade foi superior a 0,54 mm de alumínio, sem diferença entre os grupos. Conclusão: O acréscimo das substâncias radiopacificadoras aumentou a radiopacidade do adesivo e não alterou o grau de conversão e a resistência à flexão.

Avaliação radiográfica e histomorfométrica da mandíbula de ratas medicadas com glicocorticóide e bifosfonato / Mandible´s radiographic and histomorphometric assessment in female rats medicated with glucocorticoid and biphosphonate

Glicocorticóides e bifosfonatos são medicamentos que interferem na estrutura óssea. Para avaliar se estas mudanças se manifestam radiográfica e histologicamente na mandíbula, foram utilizadas 36 ratas Wistar, divididas em três grupos de 12 animais. O grupo 1 (controle) recebeu injeções subcutâneas (2 ml/kg) de solução salina, os grupos 2 e 3 receberam acetato de metilprednisolona (1 mg/kg), sendo que o grupo 3 recebeu adicionalmente risedronato (3mg/kg). Os animais foram mortos, a hemi-mandíbula esquerda foi dissecada, radiografada e submetida a processamento histológico. Um observador, cego para o grupo a que pertencia a imagem, obteve a média de densidade óptica e a proporção de trabéculas ósseas por campo. A ANOVA, complementada pelo Teste de Tukey (α=5%) evidenciou médias menores de densidade óptica no grupo 2 (glicocorticóide, 165,54±8,95), diferindo significativamente do grupo 1 (controle, 182,96±4,53) e do grupo 3 (risedronato, 180,99±6,21). Os grupos 1 e 3 não diferiram entre si. Os mesmos testes estatísticos evidenciaram diferenças significativas na proporção trabecular entre os três grupos. O grupo 2 (glicocorticóide, 53,94±12,53) apresentou a menor média e o grupo 3 (risedronato, 81,14±7,20), a maior. Ambos diferiram significativamente do grupo 1 (controle, 72,00±5,95). Em conclusão, a administração de glicocorticóides e bifosfonatos altera a proporção de trabéculas ósseas na mandíbula de ratas e estas mudanças podem ser evidenciadas radiograficamente.

Glucocorticoids and biphosphonates are drugs that interfere in bone structure. In order to assess if these changes are evident at radiographies and histological slides, 36 wistar female rats were allocated to 3 groups of 12 animals. Group 1 received saline solution (subcutaneous injections - 2 ml/kg), groups 2 and 3 received metilprednisolone acetate (1 mg/kg). Group 3 received also risedronate (3mg/kg). The animals were killed, the left hemi-mandíble was dissected, radiographed and histologically prepared. One observer blind to the group composition measured the optical density and trabecular proportion means. The ANOVA, complemented by Tukey´s test (α=5%) showed significantly smaller mean in the group 2 (glucocorticoid, 165.54±8.95) than in groups 1 (control, 182.96±4.53) and 3 (180.99±6.21). The groups 1 and 3 do not differ between themselves. The same statistical tests showed significant histological differences among groups. Group 2 (glucocorticoid, 53.94±12.53) had the smallest mean proportion of bone trabeculae per field, and group 3 (risedronate, 81.14±7.20) the largest. Both differ significantly from group 1 (control, 72.00±5.95) (F=37.56;p<0.01). In conclusion, glucocorticoid and biphosphonate administration interferes with rats mandibular trabecular proportion and these changes are radiographically detectable.