Influência do tipo de compósito e tempo de exposição aos raios-x na produção de artefatos radiográficos em modelos de restauração classe II / Influence of the type of composite and time of exposure to x-rays on the production of radiographic artifacts in class II restoration models

Objetivo: Avaliar o efeito do tempo de exposição e do tipo de compósito na produção de artefato radiográfico na interface dente/material restaurador. Materiais e Métodos: Em 20 incisivos bovinos hígidos foram feitos preparos cavitários e restaurações classe II utilizando resinas compostas Filtek Bulk Fill One (gruo 1) e a Filtek Z350 (grupo 2). Em seguida, os dentes foram expostos para obtenção das radiografias digitais, variando o tempo de exposição em 0,07, 0,10, 0,14, 0,20 e 0,25s. As imagens foram avaliadas para investigação da presença de artefato através da análise do número de pixels modificado (QPXD) e do valor médio de cinza nas restaurações de classe II (MGVR), utilizando o software Image J (Instituto Nacional de Saúde, Bethesda, MD, EUA). Resultados: Observou-se a presença de artefato em toda amostra avaliada, independente de tipo de material restaurador e tempo de exposição empregado. Não se observou diferença estatisticamente significante na QPXD e nos MGVR entre as resinas utilizadas (ANOVA 2 fatores, p p>0,05). A análise do MGVR indicou que não houve diferenças estatisticamente significativas entre as resinas nem entre os tempos de exposição (p>0,05). Observou-se uma correlação entre a QPXD e o MGVR (r=0,29) para a resina Filtek Bulk Fill One. Conclusão: Foi identificado a presença de pixels alterados sobre a dentina na região da interface dente-restauração em todos os corpos de prova. A variação do tempo de exposição como também o tipo do compósito restaurador não influenciou no aumento ou diminuição do QPXD e nem tão pouco no MGVR. Contudo houve correlação entre o QPXD e o MGVR para a resina Filtek Bulk Fill One. Pesquisas adicionais são necessárias para determinar se o QPXD representa um artefato verdadeiro ou desajuste do material restaurador ou deficiência na aplicação sistema adesivo (AU).

Objective: To evaluate the effect of the exposure time and the type of composite in the production of radiographic artifact at the tooth / restorative interface. Materials and Methods: In 20 healthy bovine incisors, cavity preparations and class II restorations were made using composite resins Filtek Bulk Fill One (group 1) and Filtek Z350 (group 2). Then, the teeth were exposed to obtain digital radiographs, varying the exposure time by 0.07, 0.10, 0.14, 0.20 and 0.25s. The images were evaluated for investigation of the presence of artifact through the analysis of the modified number of pixels (QPXD) and the average gray value in class II (MGVR) restorations, using the Image J software (National Health Institute). Results: The presence of artifact was observed in all evaluated samples, regardless of the type of restorative material and the exposure time employed. There was no statistically significant difference in QPXD and MGVR between the resins used (ANOVA 2 factors, p p> 0.05). The MGVR analysis indicated that there were no statistically significant differences between resins or between exposure times (p> 0.05). There was a correlation between QPXD and MGVR (r = 0.29) for Filtek Bulk Fill One resin. Conclusion: The presence of altered pixels on dentin in the region of the tooth-restoration interface was identified in all specimens. The variation in the exposure time as well as the type of the restorative composite did not influence the increase or decrease of QPXD and neither in MGVR. However, there was a correlation between QPXD and MGVR for Filtek Bulk Fill One resin. Further research is needed to determine whether QPXD represents a true artifact or misfit of the restorative material or deficiency in the adhesive system application (AU).

Effectiveness of Two Types of Photostimulable Phosphor Plate Plastic Barrier Envelopes for Prevention of Microbiological Contamination

Abstract Objective: To compare the effectiveness of two types of commercially available photostimulable phosphor plate (PSP) protective barrier envelopes to prevent microbiological contamination. Material and Methods: In this cross-sectional study, 80 barrier envelopes were tested in 40 volunteers. The PSP plates were placed individually in Asia Teb and Soredex protective barrier envelopes and were placed in the mouth for two minutes, similar to periapical films. The protective barrier envelopes were then removed under sterile conditions, and the sensors were placed on different culture media. The number of colonies on each plate was counted. Data were analyzed using SPSS via McNemar and Wilcoxon tests. Results: Bacterial growth was noted in 17.5% of PSPs with Soredex, and 32.5% of PSPs with Asia Teb barrier envelopes. Gram-positive bacilli were the most commonly isolated bacteria. The difference between the Asia Teb and Soredex barrier envelopes for the protection of microbiological contamination was not significant (p>0.05). Conclusion: The use of different types of protective barrier envelopes was not sufficient for prevention of microbiological contamination of PSP plates, and some adjunct modalities were required to decrease microbiological contamination of PSP plates.

Use of Mini-Implant Anchorage For Second Molar Mesialization: Comprehensive Approach For Treatment Efficiency Analysis

Abstract Objective: To approbate the complex approach for assessment of second molar mesialization outcomes with the use of orthodontic mini-implants. Material and Methods: The sample consisted of 62 patients, divided into study (n=32) and control group (n=30). Mesialization procedure in the study group was conducted with the use of braces system and orthodontic mini-implants as additional anchorage devices, while in control group mesialization was provided only with the use of the brace system. Dynamic registration of bone level changes and the entire range of tooth movement were carried out on digital orthopantomograms obtained with the use of Planmeca ProMax 2D. Results: Findings of orthopantomographic (OPG) analysis have shown that cases of second molar mesialization with the use of mini-implants as temporary anchorage characterized with more stable conditions of bone levels around displaced teeth compare to cases, where mesialization was provided only with the use of braces systems without any additional anchorage. The terms of treatment in the study group with the use of dental mini-implants as the anchorage was reduced by 8.8 ± 0.12 months compared to the control group (p<0.05). Conclusion: The use of orthodontic mini-implants as anchorage constructions during the mesialization of the mandibular second molars contributes to the reduction of treatment duration and support the more prognostic movement of teeth, that does not provoke significant pathological changes in the levels of the surrounded alveolar ridge and minimize the risk of associated periodontal complication occurrence.

Comparison of the Accuracy of Digital Radiography with Conventional Radiography and Visual Examination in the Detection of Permanent Teeth Interproximal Caries

Objective: To compared the accuracy of digital radiography in the diagnosis of interproximal caries in permanent teeth with conventional radiography and visual examination. Material and Methods: In this descriptive-analytical study, 78 human premolars, which seem normal in primary examination, are mounted on the plaster in a pair-wise manner and their caries are visually evaluated. Conventional and digital radiographic images are taken under the same conditions and their caries are graded with Confidence Score. To determine the golden standard, after mesiodistal incision, the teeth are examined using stereomicroscopy. Finally, the results obtained by visual observation and conventional radiography as well as digital images were compared with those obtained from the stereomicroscopy to determine their accuracy in detecting the interproximal caries. Results: The consistencies between the visual, digital, and conventional methods with the standard method (microscopic histology) are 53%, 78%, and 50% respectively - all of them are significant (p<0.05). The highest and the lowest sensitivities are related to the digital (96%) and visual (88%) methods respectively, while the highest and lowest specificities are related to the digital (79%) and conventional (50%) methods respectively. The highest and lowest positive predictive value is related to the digital (79%) and conventional (80%) methods respectively. The highest and lowest negative predictive values are related to the digital (90%) and visual (71%) methods respectively. Compared with the standard methodology, the most accurate diagnostic accuracy can be seen for the digital method (91%). Conclusion: There is no significant difference in the diagnosis of interproximal caries by different methods, and the only advantage of digital radiography, compared with the conventional one, is storing radiographs without losing important information and the lower dose of radiation for the patient.

Avaliação in vitro da influência de cimentos endodônticos na resistência de união sobre estrutura dentinária da câmara pulpar de dentes restaurados imediatamente e mediatamente após obturação / In vitro evaluation of the influence of endodontic cements on bond strength on the dentin structure of the pulp chamber of teeth restored immediately and immediately after filling

Este estudo teve por finalidade avaliar a influência dos cimentos endodônticos com um protocolo de irrigação na resistência de união sobre a estrutura dentinária das paredes da câmara pulpar de dentes bovinos restaurados imediatamente e após 7 dias do tratamento endodôntico. Foram avaliados os cimentos endodônticos: Cimento à base de resina epoxy (AH Plus ­ Dentsply, DeTrey, Konstanz- Alemanha) e Cimento de óxido de zinco e eugenol (Endofill ­ Dentsply Ind.com. LTDA ­ Brasil). Para a realização das restaurações foi utilizado o sistema adesivo Single Bond 2® (3M/ESPE) e a resina composta Z 350TM (3M/ESPE). 60 faces vestibulares da câmara pulpar de dentes bovinos foram distribuídos aleatoriamente em 4 grupos experimentais (G1-AHPlus Imediato; G2-AHPlus Mediato; G3-OZE Imediato; G4-OZE Mediato) e 2 controles (G5- NaOCl + EDTA Imediato e G6-NaOCl + EDTA Mediato). O protocolo de irrigação endodôntica deu-se através da imersão dos espécimes em solução de hipoclorito de sódio a 2.5% por 30 minutos e em EDTA 17% por 3 minutos. Os cimentos testados estiveram em contato com a parede dentinária pelo tempo de presa inicial, seguido de limpeza com algodão embebido em álcool 70% por 1 minuto. Os grupos experimentais de restauração mediata foram mantidos em estufa a 37ºC por 7 dias. Após o corte e a obtenção dos palitos de +/-1,0 mm² foi aplicado o teste de microtração na Máquina de Ensaios Universal e, em seguida, observados em microscópio óptico para classificação da fratura. Os valores da resistência de união foram submetidos ao teste não-paramétrico Wilcoxon-Mann-Whitney comparando dois a dois grupos a um nível de significância de 5%. Os resultados mostraram que o grupo G5 obteve menor valor de resistência de união, com diferença estatisticamente significativa (p<0,05) para os demais. O padrão de fratura mais observado nos grupos foi a coesiva em camada híbrida. Conclui-se que a associação NaOCl + EDTA diminui a resistência de união nas restaurações imediatas e que os cimentos endodônticos não alteraram a resistência de união nos períodos testados (AU).

This study aimed to evaluate the influence of endodontic sealer with an irrigation protocol on the bond strength on the dentinal structure of the pulp chamber walls of bovine teeth restored immediately and after 7 days of endodontic treatment. Endodontic sealer were evaluated: epoxy resin-based sealer (AH Plus - Dentsply, DeTrey, Konstanz- Germany) and zinc oxide and eugenol sealer (Endofill - Dentsply Ind.com. LTDA - Brazil). To perform the restorations, the Single Bond 2® adhesive system (3M / ESPE) and the composite resin Z 350TM (3M / ESPE) were used. 60 vestibular faces of the pulp chamber of bovine teeth were randomly assigned to 4 experimental groups (G1-AHPlus Immediate; G2-AHPlus Mediato; G3-OZE Immediate; G4-OZE Mediato) and 2 controls (G5- NaOCl + EDTA Immediate and G6- NaOCl + EDTA Mediato). The endodontic irrigation protocol was carried out by immersing the specimens in 2.5% sodium hypochlorite solution for 30 minutes and in 17% EDTA for 3 minutes. The tested sealers were in contact with the dentin wall for the initial setting time, followed by cleaning with cotton soaked in 70% alcohol for 1 minute. The experimental groups of mediated restoration were kept in an oven at 37ºC for 7 days. After cutting and obtaining the +/- 1.0 mm² toothpicks, the microtensile test was applied to the Universal Testing Machine and then observed under an optical microscope to classify the fracture. The bond strength values were subjected to the non-parametric Wilcoxon-Mann-Whitney test comparing two to two groups at a significance level of 5%. The results showed that the G5 group had a lower bond strength value, with a statistically significant difference (p <0.05) for the others. The most observed fracture pattern in the groups was cohesive in a hybrid layer. It is concluded that the association NaOCl + EDTA decreases the bond strength in immediate restorations and that endodontic sealer did not change the bond strength in the tested periods (AU).

Análise de sistemas reciprocantes quanto a produção de desvios e remoção de material obturador em canais radiculares: estudo in vitro / Analysis of reciprocal systems regarding the production of deviations and removal of filling material in root canals: in vitro study

O retratamento endodôntico é um procedimento realizado quando o tratamento anterior tem insucesso e visa reverter os processos infecciosos, removendo completamente o material obturador permitindo uma nova limpeza, modelagem e reobturação dos canais radiculares. Com vistas a melhoria das taxas de sucesso e eficiência do retratamento, vários sistemas de níquel-titânio (NiTi) têm sido desenvolvidos com a utilização de apenas um instrumento por meio de um movimento reciprocante, levantado novas perspectivas para o preparo biomecânico do canal radicular, bem como, o retratamento. Portanto, este estudo teve por objetivo analisar a produção de desvio e capacidade de limpeza durante retratamento dos canais mesiais de molares inferiores com curvaturas severas (30° e 70°), obturados com BioC Sealer após utilização dos sistemas reciprocantes. Uma amostra de sessenta molares inferiores foi dividida em quatro grupos experimentais, assim distribuídos: G1- X1-Blue (25.06); G2- WaveOne Gold Primary (25.07); G3- Reciproc Blue (25.08); G4- WA1 (25.07). Cada grupo continha 15 molares, totalizando 120 canais mesiais, os quais passaram pela aquisição e processamento das imagens iniciais no Microtomográfo, para que posteriormente, fosse realizado o pareamento dos grupos. Todos os grupos foram instrumentados com o sistema de rotação continua Pro Taper Next. Após instrumentação, foram obturados com cone de guta percha ProTaper Universal, selados e colocados em estufa a 37 °C, 100% de umidade durante 72 horas. Para análise de desvio e remoção da obturação dos canais as amostras foram escaneadas por meio da Microtomografia (MicroCT). Por fim, foi avaliado e medido o desvio apical através da comparação das imagens dos canais obtidas pelas Micro-CT após o retratamento, bem como a remoção do material obturador, para posterior análise estatística. Os resultados quanto a produção de desvio após remoção do material obturador, entre grupos, demonstrou não haver diferença estatisticamente significante tanto para os canais radiculares mesio vestibulares como para os canais mesio linguais (p > 0,05). Na análise intra grupo, não houve diferença em relação aos grupos G1(X1 Blue), G2 (Wave one Gold) e G3 (Reciproc Blue) (p > 0,05), porém o grupo G4 (WA1) apresentou diferença significante, mostrando maior grau de desvio no canal mesio lingual do que no mesio vestibular (p < 0,05). Com relação a remoção do material obturado, na análise entre grupo, para o canal Mesio vestibular, pode-se observar que em todos os grupos houve uma diminuição no sentido cervical para apical, porém, no grupo G4 (WA1) observou-se uma maior remoção tanto no terço médio quanto no apical. No terço cervical a maior remoção do material obturador ocorreu no grupo G2 (Wave one Gold), seguido do G4 (WA1), G3 (Reciproc Blue) e G1(X1 Blue). Para o canal mesio lingual, o grupo G4 (WA1) demonstrou uma maior estabilidade de remoção do material obturador em todos os terços. No terço cervical houve uma maior remoção do material obturador no grupo G2, seguido do G4, G3 e G1, já no terço médio foi no grupo G2, seguido do G1, G4 e G3. No terço apical, o grupo G4 promoveu maior capacidade de remoção de material obturador, seguido de G1, G2 e G3. Para comparação entre médias intragrupos, não houve diferença estatisticamente significante quando se comparou os terços cervical/médio para os Grupos G1 e G4 (tanto no canal Mesio vestibular como no mesio lingual) e terços médio/apical (apenas no canal Mesio lingual), porém, o terço apical foi observado uma maior dificuldade na remoção do material obturador. Conclui-se que a maiorias dos sistemas reciprocantes testados no retratamento promoveram desvio apical, porém o sistema WA1 foi capaz de produzir menos desvio no canal Mesio vestibular. Os sistemas reciprocantes utilizados foram capazes de remove grande parte do material obturador, mas não em sua totalidade, o terço apical foi o que mais dificultou a remoção do material obturador, porém, o sistema WA1 foi o que apresentou maior desempenho neste terço (AU).

Endodontic retreatment is a procedure performed when the previous treatment is unsuccessful and aims to reverse infectious processes, completely removing the shutter material allowing a new cleaning, modeling and reobturation of root canals. With a view to improving success rates and retreatment efficiency, several nickel-titanium (NiTi) systems have been developed with the use of only one instrument through a reciprocal movement, raising new perspectives for biomechanical preparation of the root canal, as well as retreatment. Therefore, this study aimed to analyze the production of deviation and cleaning capacity during retreatment of the mesiaal channels of lower molars with severe curvatures (30° and 70°), obtained with BioC Sealer after using reciprocating systems. A sample of sixty lower molars was divided into four experimental groups, thus distributed: G1- X1-Blue (25.06); G2- WaveOne Gold Primary (25.07); G3- Reciproc Blue (25.08); G4- WA1 (25.07). Each group contained 15 molars, totaling 120 mesiaal channels, which passed through the acquisition and processing of the initial images in the Microtomográfo, so that later, the pairing of the groups was performed. All groups have been instrumented with the continuous Rotation System Pro Taper Next. After instrumentation, they were filled with protaper universal percha gutcone, sealed and placed in a greenhouse at 37 °C, 100% humidity for 72 hours. For analysis of deviation and removal of the filling of the channels, the samples were scanned by microtomography (Micro-CT). Finally, apical deviation was evaluated and measured by comparing the images of the channels obtained by micro-CT after retreatment, as well as removal of the shutter material, for further statistical analysis. The results regarding the production of deviation after removal of the shutter material between groups, showed no statistically significant difference both for vestibular mesium root canals and for lingual mesio channels (p > 0.05). In the intra-group analysis, there was no difference in relation to groups G1(X1 Blue), G2 (Wave one Gold) and G3 (Reciproc Blue) (p > 0.05), but group G4 (WA1) showed a significant difference, showing a higher degree of deviation in the lingual mesium channel than in the vestibular mesium (p < 0.05). Regarding the removal of the obtained material, in the analysis between group, for the vestibular Mesio canal, it can be observed that in all groups there was a decrease in the cervical direction to apical, however, in group G4 (WA1) there was a greater removal in both the middle and apical third. In the cervical third the highest removal of the shutter material occurred in group G2 (Wave one Gold), followed by G4 (WA1), G3 (Reciproc Blue) and G1 (X1 Blue). For the lingual mesio channel, group G4 (WA1) demonstrated greater shutter material removal stability across all thirds. In the cervical third, there was a higher removal of the shutter material in group G2, followed by G4, G3 and G1, already in the middle third it was in group G2, followed by G1, G4 and G3. In the apical third, group G4 promoted higher shutter material removal capacity, followed by G1, G2 and G3. For comparison between intragroup means, there was no statistically significant difference when comparing the cervical/middle thirds for Groups G1 and G4 (both in the vestibular mesio channel and in the lingual mesium) and middle/apical thirds (only in the lingual Mesio canal), however, the apical third was observed a greater difficulty in removing the shutter material. It was concluded that most of the reciprocal systems tested in the retreatment promoted apical deviation, but the WA1 system was able to produce less deviation in the vestibular Mesio canal. The reciprocal systems used were able to remove much of the shutter material, but not in its entirety, the apical third was the one that most difficult to remove the shutter material, however, the WA1 system was the one that performed higher in this third (AU).

Prevalence of Dental Developmental Anomalies in Patients Attending a Faculty of Dentistry in Ajman, United Arab Emirates

Objective: To determine the prevalence of dental developmental anomalies among patients visiting the dental clinics at Ajman University, United Arab Emirates. Material and Methods: This retrospective study consisted of 425 digital panoramic radiographs. The study sample included people in the United Arab Emirates who have visited the outpatient dental clinics at the Faculty of Dentistry, at Ajman University. These OPGs have been evaluated for the presence of dental anomalies such as: Macrodontia, Microdontia, Talon cusp, Taurodontism, Dilaceration, Ectopic Eruption, Supernumerary teeth or roots, Fusion, Gemination, and Concrescense. Results: 80.7% had at least 1 anomaly, with the maximum of 5 anomalies presented in 1.2% of the sample. Dilacerations were the most commonly identified anomaly (61.4%), followed by missing third molars (22.8%), and Ectopic Eruption (15.5%) where (12.9%) of this anomaly has affected the maxillary canines. Hypercementosis (10.2%) followed by Microdontia (4.6%), which was mostly seen in the Upper laterals. Taurodontism accounted for (4.1%), Macrodontia (2.3%) and Talon cusp (2.3%). Gemination, Dens Invaginatus, and Concrescence were separately present in 1.1%, each one, of the cases observed. Conclusion: Variations in data and results among different studies suggest the impact of racial, genetic and environmental factors. The high frequency of dental anomalies emphasize the need of early detection and diagnosis which can be achieved through radiographic imaging, this would aid in further awareness to minimize any means of complexity in dental problems.

Analysis of the reproducibility of the gray values and noise of a direct digital radiography system

The aim of this study was to evaluate the reproducibility of the gray values and noise of a direct digital radiography system (Visualix eHD) for various exposure times and analyzed regions. To obtain radiographic images in a standardized manner, the digital sensor of the system and a stepwedge were positioned in a phantom at a focus-film distance of 30 cm in a dental device at 70 kV, 7 mA and 2.2 mm filtration. Ten consecutive repetitions of X-ray imaging were performed at each exposure time (0.05, 0.07, 0.09 and 0.13 s). Gray values were analyzed using ImageJ software in five regions of interest (ROIs): alveolar bone (AB), soft tissue (ST) and three steps of the stepwedge (S1, S2 and S3). The results showed that both the variability of the gray values and the noise were statistically greater (p < 0.05) in the most radiolucent region (ST). Only the noise was affected by the exposure time. In conclusion, the reproducibility of the gray values and the noise of the Visualix eHD system can vary in specific areas with different radiolucency.

Comparação de diferentes métodos de registro (a priori e a posteriori) na subtraçÆo radiográfica digital (SRD) para avaliação da produção de ruídos estruturais / Comparison of different recording methods (a priori and a posteriori) in the digital radiographic subtraction (DRS) to evaluate the production of structural noise

Objetivo: A Subtração Radiográfica Digital (SRD) é uma técnica utilizada para comparar duas radiografias de um mesmo objeto, realizadas em diferentes momentos, para demonstrar a existência de diferenças entre elas. Contudo, a reprodutibilidade da geometria de relação entre objeto, filme e fonte de raios X é indispensável para evitar a formação de ruídos estruturais. O objetivo deste trabalho foi comparar a aplicação de diferentes métodos de registros (a priori e a posteriori), em diferentes tempos de exposiçao (0,2 e 0,4 segundos), na produçÆo de ruído estrutural em imagens subtraídas. Método: dez mandíbulas foram radiografadas em duas situaçães: com uso de posicionadores convencionais sem registro e com registro a priori, sendo que ambos os métodos foram reproduzidos após 15 dias. O registro a posteriori foi realizado por meio do programa Regeemy© 0.2.43, e a subtraçÆo no programa Image Tool© 3.0. O ruído estrutural foi quantificado pelo programa Adobe Photoshop©7.0, que fornece valores de desvio padrÆo dos níveis de cinza na regiÆo de interesse (ROI). Esses valores foram submetidos à análise estatística ANOVA e teste Tukey a 5% de significância. Resultados: no tempo de exposiçÆo 0,4 s, os grupos obtiveram valores menores de desvio padrÆo em relaçÆo ao tempo de 0,2 s. Os grupos com registro a posteriori e a priori associados tiveram os menores valores de desvio padrÆo, seguidos pelos grupos com registro a posteriori. ConclusÆo: nas condiçães estudadas, o tempo de 0,4 s foi o mais adequado e a utilizaçÆo do registro a posteriori foi essencial na formaçÆo de imagens subtraídas com baixo ruído estrutural...

Objective: The Digital Radiographic Subtraction (DRS) is a technique used for comparing two radiographs of the same subject taken at different moments to demonstrate the differences between them. However, reproducibility of the geometry of relation among object, film and x-ray source is mandatory to avoid structural noise formation. The aim of this study was to compare the application of different recording methods (a priori and a posteriori) at different exposure times (0.2 and 0.4 s) on the production of structural noises in subtracted images. Method: Radiographs of 10 mandibles were taken using conventional film holders without and with a priori record, and then both methods were reproduced 15 days later. The a posteriori record was made using the Regeemy© 0.2.43 software and the subtraction was performed with Image Tool© 3.0. Results: with the 0.4 s exposure time, the groups presented lower standard deviation values compared with the 0.2 s exposure. The groups with a posteriori and a priori records had the lowest standard deviation values, followed by the groups with a posteriori record. Conclusion: Under the tested conditions, the 0.4 s exposure time was more appropriate and the use of a posteriori record was essential to obtain subtracted images with low structural noise...

Reabsorções radiculares apicais externa / External apical root resorption

A reabsorção radicular apical externa é uma patologia frequentemente encontrada em dentes permanentes. Realizouse uma revisão de literatura sobre esta patologia, do período de 1988 a 2012, no Portal CAPES, verificando métodos diagnósticos e fatores etiológicos relacionados à mesma. Concluiu-se que: o método radiográfico mais efetivo para detecção de reabsorções radiculares apicais externas são as tomografias computadorizadas por feixes cônicos, embora as mais indicadas sejam as periapicais, especialmente as digitais; os fatores genéticos demonstraram associação com o grau de reabsorção, enquanto o gênero e a idade não; deve-se observar os fatores etiológicos da reabsorção para determinar um adequado tratamento; todos os tratamentos ortodônticos levam à reabsorção radicular apical externa, que cessam com o término da mecanoterapia, o formato radicular e a presença de reabsorções prévias em exames radiográficos estão associados a um maior grau de reabsorção e devem ser observadas através de exames radiográficos.

External apical root resorption is a common pathology found in permanent teeth. This article presents a literature review from 1988 to 2012, searched in Portal CAPES, about the diagnostic methods and etiologic factors related with this pathology. The following conclusions were: the cone beam computed tomography is the most effective method to detect external apical root resorptions, although periapical radiographs are more indicated, of preference digital; genetic factors showed association with the degree of the resorption, while age and gender do not; etiologic factors should be observed to determine an adequate treatment; all orthodontic treatment lead to external apical root resorption, which stops with the end of the mechanotherapy, radicular form and the presence of previous resorptions in radiographies have an association with a higher degree of resorption and should be observed using radiographic exams.

Distinção entre Dois Tipos de Lesão Dentinária na Superfície Oclusal sob Esmalte sem Cavitação / Distinction between Two Types of Dentine Lesion on the Occlusal Surface without Cavitation Enamel Under

Introdução: Embora a prevalência de cárie tenha diminuído consideravelmente, as superfícies oclusais ainda representam as áreas com maior proporção de experiência dessa lesão. Por outro lado, atualmente os clínicos e a comunidade científica têm detectado uma grande ocorrência de lesões dentinárias oclusais sob esmalte aparentemente hígido. Essas lesões têm sido denominadas de cárie oculta porque se mostram clinicamente com superfície oclusal sem cavitação e com evidente manifestação em dentina, quando da execução do exame radiográfico. Objetivo: O objetivo desse trabalho é distinguir dois tipos de lesão dentinária, sob esmalte sem cavitação, apresentando uma nova denominação, cárie semioculta, para todas as lesões dentinárias sob esmalte não cavitado, porém com mudança de coloração, visível através da inspeção visual detalhada, classificando as duas entidades distintas de cárie escondida, cárie oculta e semioculta, baseando-se no método de diagnóstico. A diferenciação entre as lesões será ilustrada através de fotografias, ressaltando os aspectos clínicos de ambas as situações.Conclusão: A introdução no meio científico dessa nova denominação é bastante relevante tendo em vista que as pesquisas mostram uma taxa relativamente alta da prevalência da cárie oculta porque consideram apenas a ausência da cavitação no esmalte, sem a observação da mudança na sua configuração e coloração. Entretanto, se verifica que a maioria dessas lesões é cárie semioculta, portanto detectáveis pela inspeção visual detalhada, e que a cárie oculta, encontrada em menor percentual, não é perceptível através da inspeção visual detalhada, mas plenamente visível através da radiografia. As evidências clínicas impõem a necessidade da constante evolução e modificação de conceitos e técnicas operatórias

Introduction: Although caries prevalence has decreased considerably, the occlusal surfaces still represent areas with higher proportion of experience of this injury. Moreover, currently the clinical and scientific community have found a high occurrence of occlusal dentin lesions in apparently healthy enamel. These lesions have been called hidden caries because they show clinically the occlusal surface without cavitation and with evident manifestation in dentin when executing radiographic examination. Objective: The aim of this work is to distinguish two types of dentinlesion, no cavitation in enamel, with a new name, almost hidden caries, for all lesions in enamel dentin cavitated not, but with color change, visible through the detailed visual inspection, classifying the twoseparate entities hidden caries, hidden caries and almost hidden caries, based on the method of diagnosis. The differentiation between the lesions will be illustrated by photographs, emphasizing the clinical aspects of both situations.Conclusion: The introduction of this new in the scientific name is very relevant given that polls show a relatively high prevalence of hidden caries because they take into account only the absence of cavitation inenamel without notice of the change in shape and color . However, it appears that the majority of these injuries is almost hidden cariestherefore detectable by detailed visual inspection, and that the hidden caries, found at a lower rate is not noticeable through visual detail, but fully visible by radiography. The clinical evidence imposes the need for constant evolution and change of concepts and surgical techniques

Comparação das imagens radiográficas digitais e convencionais em reabsorções ósseas periodontais / Comparison of the conventional and digital radiographic image in periodontal bone resorption

Objetivo: Analisar os defeitos ósseos periodontais, pela comparação das imagens digitais (utilizando as ferramentas do Digora fmx 2.5) com as convencionais na angulação de -10, 0 e +10º, pela análise de três observadores. Métodos: Para obtenção das imagens foi utilizado um aparelho de Raio-X convencional, com padronização da tomada radiográfica, pela utilização do posicionador do tipo Rinn® e moldagem de resina das superfícies oclusais dos dentes a serem radiografados, nas três incidências radiográficas utilizadas. O contraste e a densidade foram padronizados no emprego do sistema digital Digora, com as exposições dos Raio-X adequadas a cada região. As radiografias convencionais foram realizadas com películas do tipo Insight da marca Kodak nº 2. As imagens digitais foram analisadas no monitor do computador por meio do software do Digora 2.5, utilizando a ferramenta para alterações das imagens padrão, 3D e negativa e as convencionais observadas em um negatoscópio apropriado. Resultados: O resultado estatístico demonstrou diferença significativa na análise entre os observadores, quanto às imagens obtidas, as digitais produziram imagens consideradas de qualidade inferior sem alterações das ferramentas em comparação à radiografia convencional e quando a imagem digital era alterada (brilho, contraste, 3D), a qualidade aumentava significativamente, sendo comparável à produzida pela película convencional. Quanto ao ângulo de incidência do feixe dos Raio-X, não foram detectadas diferenças significativas entre os mesmos, ocorrendo o mesmo quanto ao lado radiográfico. Conclusão: Os métodos radiográficos convencionais e digitais (quando da utilização das ferramentas para alteração das imagens) não demonstraram diferenças estatísticas na efetividade da quantificação dos defeitos ósseos periodontais.

Objective: To assess periodontal bone defects, comparing the digital images (using the tools of Digora® fmx 2.5) with the conventional angle of -10, 0 and 10 degrees, through the three evaluators analysis. Methods: To obtain the images we used a conventional X -ray machine with standardized radiography, using the positioner type Rinn and resin molding of the occlusal surfaces of teeth to be X-ray in three radiographic. The contrast and density were standardized in the use of digital Digora with X-ray exposures appropriate to each region. The radiographs were performed with films Kodak Insight brand 2. Digital images were analyzed on the computer monitor through Digora 2.5 software, using the tool to change the default images, 3D and conventional negative and observed in an appropriate light box. Results: The results of statistical analysis showed significant difference between the observers in the images obtained, the digital images produced poor quality images without changing tools in comparison to conventional radiography and when the digital image was changed (brightness, contrast, 3D), the quality increased significantly, as compared to that produced by conventional film. As the angle of incidence of the x-rays beam, there were no significant differences between them, the same happened on the radiographic side. Conclusion: The conventional and digital radiographic methods (when using the tools to change the images), showed no statistical differences in the effectiveness of the quantification of periodontal bone defects.

Ventajas de la radiología digital intrabucal / Advantajes of the intraoral digital radiology

En la actualidad, la radiografía digital (RD) es considerada un método moderno de diagóstico que tiene la ventaja de la observación inmediata de la imagen sin la utilización de contaminantes químicos para su obtención, además requiere menor radiación que la radiografía conevencional. También se pueden almacenar y enviar las imágenes solamente con el clik del botón del mouse. Sin embargo, hay estudios que indican que la incorporación a la práctica profesional se va efectuando lentamente. Implementar la RD en el consultorio odontológico requiere un adiestramiento adicional para el profesional que redunda en beneficio del paciente con nuevas posibilidades diagnósticas. El objetivo de este trabajo fue realizar una revisión de las ventajas y desventajas que tiene la RD intrabucal en la actualidad.

The comparison of subjective image quality in conventional and digital panoramic radiography.

OBJECTIVE: The purpose of this study was to compare the subjective image quality of (1) regular intensifying screens with medium intensifying screens, (2) regular intensifying screens with digital radiography, and (3) medium intensifying screens with digital radiography for panoramic radiographs. MATERIALS AND METHODS: Forty-five patients participated and a total of 90 radiographs were obtained in the study. The patients were divided into three groups (regular-medium intensifying screen, regular intensifying screen-digital radiography, and medium intensifying screen-digital radiography) that consisted of 15 people each. All radiographs were assessed by three oral radiologists independently. The observers evaluated the images using a 3-point scale (1=well visible, 0=partly visible, -1=not or hardly visible) for anatomical structures and pathological findings that are commonly found on panoramic radiographs. Subjective image quality of the groups and comparison of the observers were assessed by using non parametric Kruskal Wallis and Mann-Whitney U tests. RESULTS: For all groups and observers, no statistically significant difference (p>0.05) was found for both anatomical structures and pathologies and between anatomical structures and pathologies according to the Mann Whitney U test. In comparison with observers, no statistically significant difference (p>0.05) was found for both anatomical structures and pathologies and between anatomical structures and pathologies for all groups according to the Kruskal Wallis test. CONCLUSION: The subjective image quality of medium and regular intensifying screens and conventional and digital panoramic radiographs were found statistically equal in this study.

Evaluation of the effects of processing delays and protective plastic cases on image quality of a photostimulable phosphor plate system

This ex vivo study evaluated the quality of digital radiographic images obtained with the photostimulable phosphor plate system (Digora) according to the processing delay and maintenance of optical plates in either opaque (supplied with the system) or transparent protective plastic cases during this period. Five radiographs were obtained from the mandibular molar region of a dry human mandible using optical plates. These plates were placed in the protective plastic cases before obtaining the radiographs and were processed immediately or after processing delays of 5, 60 and 120 min, when the case was removed. The results revealed a reduction in image quality when processing was delay 120 min compared to the other times. The opaque case provided better protection to the sensor than the transparent case. In conclusion, a 120-min processing delay for the Digora system caused a reduction in image quality, yet without interfering with the quality of diagnosis. The opaque case supplied by the system's manufacturer provided better protection to the optical plate than the transparent case.

Confiabilidad de dos aparatos digitales en relación a la veracidad de las mediciones / Trastworthiness of two digital devices related to the accuracy of measurements

El objetivo de este estudio fue comparar dos aparatos digitales directos con la radiografía periapical convencional y con la medida real evaluada por un vernier digital analizando los resultados en relación al grado de fidelidad de las mediciones. Fueron utilizados veinte dientes íntegros unirradiculares permanentes en que se realizó la medida con el vernier. En seguida, se incluyo en cera utilidad 7, se hizo las radiografías utilizando las técnicas periapicales digitales y convencional. Para la incidencia radiográfica, el aparato utilizado fue el 765 DC® (Gendex® -Il- USA), con 65 kVp, 7mA, 30cm de distancia foco- película, 0.02s y 0,16s de tiempo de exposición para el digital y convencional respectivamente. Los aparatos digitales directos utilizados fueron: el RVG® (Trophy,Vallée- Francia) y el Visualix® (Gendex® -Il- USA) . La medida de los elementos dentarios fue realizada mediante la propia herramienta de medida de los aparatos digitales. Para la técnica convencional, la medida fue realizada por un vernier digital. Con los valores obtenidos, se realizó el test Tuckey y el test t pareado con corrección de Bonferroni. Los resultados indican tener diferencias estadísticamente significantes. Sin embargo, concluimos que los sistemas digitales directos y el método convencional son confiables en la utilización de las mediciones en la práctica odontológica y que el Visualix presentó los mejores resultados

The aim of this study was compared two direct digital devices with the periapical radiograph and with the real measure evaluated by a digital caliper being analyzed the results how to the degree of allegiance of the measurement. Twenty uniroot permanent teeth were utilized to realize the digital caliper measurement. After that, the teeth were included in nº7 wax utility and conventional periapical and digital radiographs were taken. The X-Ray machine used was the 765 DC® (Gendex® -Il- USA) with 65 kVp, 7mA, 30cm distance focus- film and exposure time to digital and conventional periapical of the 0.02s and 0,16s respectively. The direct digital devices used were the RVG® (Trophy,Vallée- France) and the Visualix® (Gendex® -Il- USA). The measurement of the teeth were realized using the own measure tool of the digitals devices software. To conventional technique, the digital caliper were used to realize the measurement. The values obtained were submitted to Tukey test and t paread test with the Bonferroni correction. The results showed possess statistically significant difference. However, it's possible to conclude that the direct digital devices and the conventional method are trustworthily in measurement in the dental clinical pratice, being the Visualix® showed the best results.

O objetivo deste estudo foi comparar dois sistemas digitais diretos, com a radiografia periapical convencional e com a medida real avaliada por um paquímetro digital, analisando os resultados quanto ao grau de fidelidade das mensurações. Foram utilizados vinte dentes hígidos unirradiculares permanentes o qual foi realizada a mensuração com um paquímetro digital. Posteriormente, foram incluídos em cera utilidade 7, radiografados utilizando as técnicas periapicais digitais e convencionais. Para a incidência radiográfica, o aparelho utilizado foi o 765 DC® (Gendex® -Il- USA), com 65 kVp, 7mA, 30cm de distância foco- filme, 0.02s e 0,16s de tempo de exposição para o digital e convencional respectivamente. Os aparelhos digitais diretos utilizados foram : o RVG® (Trophy,Vallée- França) e o Visualix® (Gendex® -Il- USA). A mensuração dos elementos dentários foi realizada mediante a própria ferramenta de medida dos aparelhos digitais. Para a técnica convencional, a mensuração foi realizada mediante um paquímetro digital. Para os valores obtidos, foi realizado o teste Tuckey e o teste t pareado com correção de Bonferroni.Os resultados mostraram possuir diferenças estatisticamente significantes, apesar disso, concluímos que os sistemas digitais diretos e o método convencional são confiáveis na utilização das mensurações, sendo que o VISUALIX apresentou os melhores resultados.

Reproducibility of pixel values for two photostimulable phosphor plates in consecutive standardized scannings / Reprodutibilidade dos valores de "pixels" de duas placas de fósforo fotoestimuláveis em leituras padronizadas consecutivas

The objective of the present study was to determine the reproducibility of the pixel values obtained with the Digora system (Soredex, Finland). Exposures were standardized, with variation in exposure and scanning time of two photostimulable phosphor plates containing a stepwedge image. The smallest variation in pixel values ranged from 50 to 75 percent, with the widest variations being observed in less dense steps. A significant difference in pixel values was observed in terms of X-ray exposure and scanning times and between the two plates themselves (ANOVA, p < 0.01). Using the present methodology, the reproducibility of pixel values was not satisfactory for the tested white photostimulable plates. This wide variation in digitalization might be influenced by the amount of X-rays that sensitized the plates. It may be important to establish the reproducibility of the pixel values in quantitative studies using digital image.

O objetivo do presente trabalho foi determinar a reprodutibilidade dos valores de "pixels" obtidos com o sistema Digora (Soredex, Finlândia). As exposições foram padronizadas, com variação no tempo de exposição e leitura de duas placas de fósforo fotoestimuláveis contendo a imagem de um penetrômetro. A menor variação nos valores de "pixels" foi de 50 a 75 por cento, sendo as maiores variações oriundas nas faixas mais claras. Uma diferença significante nos valores de "pixels" foi observada em relação ao tempo de exposição e leitura das placas e entre as duas placas (ANOVA, p < 0,01). Utilizando a presente metodologia, a reprodutibilidade dos valores de "pixels" das placas testadas do sistema Digora não foi satisfatória. Essa grande variação na digitalização pode ter sido influenciada pela quantidade de Raios X que sensibilizou as placas. Isso pode ser importante para estabelecer a reprodutibilidade dos valores de "pixels" em estudos quantitativos usando imagem digital.

Digital intra-oral radiology: An overview of the current digital radiographic technologies and author's personal experience with Schick's CDR system

Digital imaging is a revolutionary radiographic technology. The era of digital imaging in dentistry has certainly commenced. The aim of this article is to bring the dentists [up to date] with digital intra-oral radiographic system and discuss its present and future applications. In this article an attempt has been made to enhance the awareness of dentists as regards to the benefits of digital intra-oral radiology. This will give an insight into the application, interpretation, results and the tremendous progress of this latest technology. This article also includes the personal experience of the author with Schick's CDR that the author has been using since 1994. A comparison has also been made between various systems available in the market

Validade do exame radiográfico digital no diagnóstico de lesões proximais em molares decíduos / Validity of the digital systen in the diagnosis of proximal caries in primary molars

O estudo avaliou o desempenho diagnóstico do filme Ekaspeed plus e do sistema digital Digora por meio de uma amostra de 37 molares decíduos. As imagens de 41 superfícies proximas foram avaliadas sob condições padronizadoras e cinco recursos de edição de imagem (x0,5, x1, x2, Negativo e 3D), disponíveis no software do sistema digital, foram utilizados. Após a secção dos dentes e a validação em estereomicroscopia (x40), calculou-se a sensibilidade, especificidade, acurácia e Kappa não-ponderado dos métodos. O sistema digital Digora foi mais sensível que os filmes, nos dois cul-off estudados. Com o filme Ektaspeed plus, o método radiográfico convencional foi tanto ou mais específico que o sistema digital, ao diagnosticar todas as lesões e lesões dentinárias, entretanto de menor acurácia quando comparados às modalidades de imagem digital. O valor de Kappa obtido pelo filme, assemelhou-se ao de algumas modalidades de imagem do sistema digital Digora, no diagnóstico de todas as lesões, o que não ocorreu no diagnóstico de lesões dentinárias. Cohen's Kappa revelou boa concordância intra-examinador (0,758). Devido aos resultados observados, o sistema digital demonstrou-se comparável ao método radiográfico convencional, no diagnóstico de lesões de cárie em superfícies proximas de molares decíduos

Image quality in digital radiographic systems

The aim of the present study was to evaluate the image quality of four direct digital radiographic systems. Radiographs were made of the maxillary central incisor and mandibular left molar regions of a dry skull, and an aluminum step-wedge. The X-ray generator operated at 10 mA, 60 and 70 kVp, and images were acquired with 3, 5, 8, 12, 24 and 48 exposure pulses. Six well-trained observers classified the images by means of scores from 1 to 3. Collected data were submitted to nonparametric statistical analysis using Fisher's exact test. Statistical analysis showed significant differences (p<0.01) in image quality with the four systems. Based on the results, it was possible to conclude that: 1) all of the digital systems presented good performance in producing acceptable images for diagnosis, if the exposures of the step-wedge and the maxillary central incisor region were made at 5 pulses, as well as at 8 pulses for the mandibular left molar region, selecting 60 or 70kVp; 2) higher percentages of acceptable images were obtained with the administration of lower radiation doses in CCD-sensors (charge-coupled device); 3) the Storage Phosphor systems produced acceptable images at a large range of exposure settings, that included low, intermediate and high radiation doses