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

Influência da penetração de instrumentos, empregados na condensação lateral ativa, na qualidade da obturação de canais radiculares

PURPOSE: the purpose of this study was to compare the quality of the obturation and the difference of penetration depth inside the root canal of the instruments Finger Spreader, file type Kerr, Flexofile and Nitiflex when used as spreaders during the filling by Active Lateral Condensation Technique. MATERIAL AND METHOD: 40 extracted permanent human teeth were instrumented by the Modified Goerig Technique and divided in four groups. In the group I the finger spreader was used; in the group II, files type Kerr was used; in the group III, files Flexofile was used and, in the group IV, files Nitiflex, all number 30, for space opening for placement of the secondary cones, during the Technique of Active Lateral Condensation. The radiographic quality of the obturation and the depth of penetration of the instruments was evaluated and analysed statisticaly (Kruskal-Wallis and Dunn's Test). RESULTS AND CONCLUSION: with relationship to the radiograph analysis of the quality of the filling, the group II was what it presented the best result, followed by the groups I, IV and III, respectively. In relation to the depth of penetration of the instruments, the group IV approached more the desired distance, or, 1 millimeter less than the length of the work, followed, respectively, by groups II, III and I.OBJETIVO: comparar a qualidade da obturação e a diferença de profundidade de penetração, no interior do canal radicular, dos espaçadores digitais (Finger Spreader), limas tipo Kerr, Flexofile e Nitiflex, quando utilizados como espaçadores, durante a obturação pela Técnica da Condensação Lateral Ativa. MATERIAL E MÉTODOS: foram utilizados 40 dentes molares permanentes humanos, extraídos, instrumentados pela Técnica de Goerig Modificada e divididos em quatro grupos. No grupo I foi utilizado o espaçador digital C; no grupo II, lima tipo Kerr; no grupo III, lima Flexofile e, no grupo IV, lima Nitiflex, todos com diâmetro (D1) ou diâmetro da ponta correspondente ao diâmetro de uma lima 30 (0,30mm), para abertura de espaço para colocação dos cones secundários, durante a Técnica da Condensação Lateral Ativa. Avaliou-se e submeteu-se à análise estatística (Kruskal-Wallis e teste de Dunn) a qualidade radiográfica da obturação e a profundidade de penetração dos instrumentos. RESULTADOS E CONCLUSÃO: quanto à análise radiográfica da qualidade da obturação, o grupo II foi o que apresentou o melhor resultado, seguido dos grupos I, IV e III, respectivamente. Em relação à profundidade de penetração dos instrumentos, o grupo IV aproximou-se mais da distância desejada, ou seja, 1 milímetro aquém do comprimento de trabalho, seguido, respectivamente, dos grupos II, III e I

Biocompatibility and setting time of CPM-MTA and white Portland cement clinker with or without calcium sulfate

To evaluate the biocompatibility and the setting time of Portland cement clinker with or without 2% or 5% calcium sulfate and MTA-CPM. Twenty-four mice (Rattus norvegicus) received subcutaneously polyethylene tubes filled with Portland cement clinker with or without 2% or 5% calcium sulfate and MTA. After 15, 30 and 60 days of implantation, the animals were killed and specimens were prepared for microscopic analysis. For evaluation of the setting time, each material was analyzed using Gilmore needles weighing 113.5 g and 456.5 g, according to the ASTM specification Number C266-08 guideline. Data were analyzed by ANOVA and Tukey's test for setting time and Kruskal-Wallis and Dunn test for biocompatibility at 5% significance level. Histologic observation showed no statistically significant difference of biocompatibility (p>0.05) among the materials in the subcutaneous tissues. For the setting time, clinker without calcium sulfate showed the shortest initial and final setting times (6.18 s/21.48 s), followed by clinker with 2% calcium sulfate (9.22 s/25.33 s), clinker with 5% calcium sulfate (10.06 s/42.46 s) and MTA (15.01 s/42.46 s). All the tested materials showed biocompatibility and the calcium sulfate absence shortened the initial and final setting times of the white Portland cement clinke

Efficacy of the NaviTip FX irrigation needle in removing calcium hydroxide from root canal

Objective: To evaluate the effectiveness of the NaviTip FX, brush-covered irrigation needle, in removing calcium hydroxide from the root canal. Study Design: Thirty single-rooted teeth were randomly divided into three groups: A - irrigation with a hypodermic needle inserted as far as possible without binding and activation with #30 K-type file; B - Irrigation with a hypodermic needle without activation; C - irrigation with NaviTip FX needle. Sodium hypoclorite 1% was used in irrigation. The root canals were examined trough scanning electron microscopy. Calcium hydroxide removal was recorded at 1, 5, and 10mm from the working length (WL) and the data were analysed using one-way ANOVA test (p<0.05). Results: NaviTip FX and hypodermic needle activated with #30K-type file showed lower score at 10 and 5mm with no significant difference between them. Comparison within groups did not show significant differences. All groups showed significantly better smear layer removal at 5 and 10 mm from the WL. Conclusion: The apical third (1mm) of the root canal was found to be the most critical site for Ca(OH)2 removal

Influência da penetração de instrumentos, empregados na condensação lateral ativa, na qualidade da obturação de canais radiculares

OBJETIVO: comparar a qualidade da obturação e a diferença de profundidade de penetração, no interior do canal radicular, dos espaçadores digitais (Finger Spreader), limas tipo Kerr, Flexofile e Nitiflex, quando utilizados como espaçadores, durante a obturação pela Técnica da Condensação Lateral Ativa. MATERIAL E MÉTODOS: foram utilizados 40 dentes molares permanentes humanos, extraídos, instrumentados pela Técnica de Goerig Modificada e divididos em quatro grupos. No grupo I foi utilizado o espaçador digital C; no grupo II, lima tipo Kerr; no grupo III, lima Flexofile e, no grupo IV, lima Nitiflex, todos com diâmetro (D1) ou diâmetro da ponta correspondente ao diâmetro de uma lima 30 (0,30mm), para abertura de espaço para colocação dos cones secundários, durante a Técnica da Condensação Lateral Ativa. Avaliou-se e submeteu-se à análise estatística (Kruskal-Wallis e teste de Dunn) a qualidade radiográfica da obturação e a profundidade de penetração dos instrumentos. RESULTADOS E CONCLUSÃO: quanto à análise radiográfica da qualidade da obturação, o grupo II foi o que apresentou o melhor resultado, seguido dos grupos I, IV e III, respectivamente. Em relação à profundidade de penetração dos instrumentos, o grupo IV aproximou-se mais da distância desejada, ou seja, 1 milímetro aquém do comprimento de trabalho, seguido, respectivamente, dos grupos II, III e I

Análise de Defeitos Ósseos Utilizando a Radiografia Convencional e Sistema de Imagem Digital Digora

ResumoFoi avaliada a precisão das imagens digitais, obtidas com o Sistema Digora e radiografias convencionais, na localização e visualização de defeitos ósseos criados experimentalmente, em mandíbulas humanas secas.As imagens digitalizadas, padrão, 3D e com inversão de contraste, foram comparadas com as radiografias convencionais, obtidas com filmes Ekta-speed Plus EP-21 da Kodak.Os resultados mostraram que os defeitos produzidos no osso cortical foram melhores detectados do que os do osso esponjoso. A radiografia convencional foi a que melhor mostrou o defeito do osso cortical e a digitalizada no osso esponjoso. Entre as digitalizadas a melhor foi a padrão e com inversão de contraste. Em todas as imagens, radiografia convenciona e digitalizadas os defeitos somente foram visualizados quando alcançou o tamanho de uma broca número 6.AbstractThis study evaluated the accuracy of conventional radiography and photostimulate phosphor plate system in localizing and visualizing experimentally created bone defects.Dry human mandibles with good bone integrity in the evaluated regions were selected. The bone defects were performed on the mandibule external face from the central incisors to the first premolar and within the posterior teeth sockets, using round burs # 2, 4, 6, 8 and 10, in low rotation.The mandibles were radiographed with Ekta-speed Plus EP-21 Kodak film and optical plates of the Digora system. The visualization of bone defects was performed in the radiographic images, with the aid of a viewbox; in the digital images (standard, 3D, contrast inversion), it was performed in the computers screen, with the support of Windows for Digora software. The findings showed that the bone defect in cortical bone are best viewed in conventional radiography and in cancelous bone are best in digital images. When digitized images were compared it was observed that standard and contrast invertion images were more accurate than those in 3D, in the visualization of bone defects

Clinical and radiographic analysis of extrusion of ca lcium hydroxide paste in teeth with periapical lesions

It has been evaluated clinically and radiographically the effect of the extrusion of calcium hydroxide paste in teeth with periapical lesions. Twenty-five patients with teeth showing pulp necrosis and periapical lesions were submitted to endodontic treatment. Dressing calcium hydroxide paste, iodoform and propylene glycol were used. Clinically, the symptoms were evaluated after treatment and, radiographically, the reabsorption of extravasated paste and repair process of the periapical lesion. Only three patients had symptoms severe in the first 24 hours, the paste was completely reabsorbed within 15 days and no interference in the repair process.Avaliou-se, clínica e radiograficamente, o efeito do extravasamento da pasta de hidróxido de cálcio em dentes com lesões periapicais. Vinte e cinco pacientes com dentes exibindo necrose pulpar e lesão periapical foram submetidos a tratamento endodôntico. Como medicação intracanal foi usada pasta de hidróxido de cálcio, iodofórmio e propilenoglicol. Avaliou-se, clinicamente, a sintomatologia após o tratamento e, radiograficamente, a reabsorção da pasta extravasada e o processo de reparo da lesão periapical. Somente três pacientes apresentaram sintomatologia intensa nas primeiras 24 horas, sendo que a pasta foi totalmente reabsorvida em 15 dias e não houve interferência no processo de reparo