The use of ultrasound for cleaning the surface of stainless steel and nickel-titanium endodontic instruments.

AIM: The aim of this study was to evaluate the efficacy of ultrasound in cleaning the surface of stainless steel and Ni-Ti endodontic instruments. METHODOLOGY: Twenty nickel-titanium instruments (10 Quantec files and 10 Nitiflex) and 20 stainless steel K-files (10 Maillefer-Dentsply and 10 Moyco Union Broach) were removed from their original packages and evaluated using a scanning electron microscope. Scores were given for the presence of residues on the surface of the instruments. The instruments were then cleaned in an ultrasonic bath containing only distilled water or detergent solution for 15 min, and re-evaluated, using scanning electron microscopy. RESULTS: Before cleaning, a greater amount of metallic debris was observed on the nickel-titanium Quantec instruments (P < 0.05), when compared to those made of stainless steel. Statistical analysis showed that the use of ultrasound was effective for cleaning the instruments, regardless of the irrigating solution or the instruments type (P < 0.05). CONCLUSIONS: The use of ultrasound proved to be an efficient method for the removal of metallic particles from the surface of stainless steel and Ni-Ti endodontic instruments.

In vitro evaluation of the antimicrobial activity of a castor oil-based irrigant.

The antimicrobial activity of irrigating solutions--Endoquil (castor oil detergent), 2% chlorhexidine gluconate solution, and 0.5% NaOCl solution-was evaluated against gram-positive cocci (Micrococcus luteus, Staphylococcus aureus, Enterococcus faecalis, Staphylococcus epidermidis, Streptococcus mutans, and Streptococcus sobrinus), gram-negative rods (Escherichia coli and Pseudomonas aeruginosa), and the yeast Candida albicans. Activity was evaluated using the two-layer agar diffusion technique. The base layer was obtained by pouring 10.0 ml of Muller Hinton Medium or 10.0 ml of Brain Heart Infusion agar in a Petri dish. After solidification a 5.0 ml seed layer of Muller Hinton Medium or Brain Heart Infusion agar with inoculum (106/ml) was added. Absorbent paper disks (6.0 mm in diameter) immersed in the solutions were placed at equidistant points. Plates were maintained at room temperature for 2 h for prediffusion of the solutions and incubated at 37 degrees C for 24 h. The candle jar system was used for the Brain Heart Infusion agar plates. All tests were performed in duplicate. After incubation the medium was optimized with 0.05 g% triphenyltetrazolium chlorate gel and inhibition halos were measured. All bacterial strains were inhibited by 2.0% chlorhexidine gluconate. Endoquil was effective against gram-positive microorganisms, and 0.5% NaOCl was effective only against S. aureus.

Release of formaldehyde by 4 endodontic sealers.

OBJECTIVE: The purpose of this study was to evaluate the release of formaldehyde by some root canal filling materials. STUDY DESIGN: Two older endodontic sealers, AH 26 and Endomethasone, and 2 recently available sealers, AH Plus and Top Seal, were analyzed. Infrared and electronic spectroscopy were used to determine formaldehyde content after set of the materials. RESULTS: Analysis showed that the AH 26 and Endomethasone sealers released formaldehyde. Although the AH Plus and Top Seal sealers have similar chemical composition, they released formaldehyde in a minimal concentration. CONCLUSIONS: The AH 26 and Endomethasone sealers released formaldehyde after setting; however, a minimum release was observed for the AH Plus and Top Seal sealers.

The influence of ultrasound in removing intraradicular posts.

Thirty single-rooted teeth were prepared to receive cast posts. After cementation of the post the teeth were divided into three groups. Group I did not receive any treatment, whereas the posts in groups II and III were treated with an ultrasonic device, for 2 min and 5 min, respectively. The force required for post removal was determined using a universal test machine. No statistical differences (P > 0.05) were found between the groups where ultrasound had been used. Significantly reduced forces were necessary to remove the posts from group II and III, compared with group I which did not receive ultrasonic treatment (P < 0.05).

The influence of ultrasound in removing intraradicular posts.

Thirty single-rooted teeth were prepared to receive cast posts. After cementation of the post the teeth were divided into three groups. Group I did not receive any treatment, whereas the posts in groups II and III were treated with an ultrasonic device, for 2 min and 5 min, respectively. The force required for post removal was determined using a universal test machine. No statistical differences (P > 0.05) were found between the groups where ultrasound had been used. Significantly reduced forces were necessary to remove the posts from group II and III, compared with group I which did not receive ultrasonic treatment (P < 0.05).

Teste de provocacao bronquica com carbacol no diagnostico de asma. Relato de casos e comentarios. / Bronchial provocation test with carbachol in the diagnosis of asthma. Report of cases and comments

O teste de provocacao bronquica com carbacol e usado para demonstrar a presenca de hiperreatividade bronquica, a qual e universal entre os portadores de asma bronquica. Isto permite o diagnostico ou nao da doenca em diversas situacoes clinicas frequentes. Atraves do relato de casos e revisao bibliografica, e demonstrada a importancia deste teste em casos de:suspeita de asma de inicio recente, com exame clinico-funcional normal; tosse persistente e dispneia como manifestacoes isoladas de asma; diagnostico diferencial da asma bronquica e cardiaca; asma ficticia; e refluxo gastresofagiano simulando asma

Marcadores biologicos em carcinoma bronquico. / Biological markers in bronchial carcinoma

Em um grupo de 27 pacientes de carcinoma bronquico foram estudados, como marcadores biologicos, o antigeno carcinoembrionario, progesterona, hormonio luteinizante, insulina, prolactina, estradiol, hormonio foliculo estimulante, tiroxina, hormonio de crescimento, cortisol, testosterona, tri-iodotironina, hormonio estimulante da tiroide. Em 24 pacientes, um ou mais marcadores biologicos estavam aumentados; o antigeno carcinoembrionario, hormonio luteinizante, progesterona e a insulina apresentaram valores aumentados entre 35 e 50% dos pacientes, enquanto que o hormonio de crescimento, tiroxina, cortisol, testosterona, tri-iodotironina e o hormonio estimulante da tiroide so estavam elevados em menos de 5%; os demais situaram-se entre aqueles valores. Nos pacientes analisados de forma seriada, o unico marcador que apresentou correspondencia com a evolucao do processo tumoral foi o antigeno carcinoembrionario

Nodulo isolado de pulmao: clinica, diagnostico e indicacao cirurgica. / Solitary isolated nodule: clinics, diagnosis and surgical indication

Estudaram-se 42 casos de nodulo isolado de pulmao, todos com diagnostico anatomopatologico. Encontraram-se 27 individuos com neoplasias malignas, todos acima de 40 anos. Os dados radiologicos auxiliaram na identificacao da etiologia do nodulo: em 74% dos casos de nodulos, que ao raio-X mostravam diametro igual ou maior que 3 centimetros, verificou-se malignidade.Surpreendentemente, encontrou-se um caso em que o nodulo era calcificado e revelouse maligno. Sinais radiologicos como umbilicacao, traves perifericas ou corona radiada, isolados ou em associacao, mostraram-se sugestivos de malignidade. Com o diagnostico clinico e armado, pudemos evitar toracotomias desnecessarias ou retardamento na indicacao cirurgica dos nodulos potencialmente malignos

A relacao "A/V" do pulso venoso jugular na estenose pulmonar - estudo de 60 casos com comprovação hemodinâmica e/ou cirúrgica / The A-V ratio of jugular venous pulse in pulmonary stenosis - study of 60 cases with hemodynamic and/or surgical confirmation

Estudou-se a amplitude da onda "a" em relacao a da onda "v" (A/V), do pulso venoso jugular (PVJ) em um grupo de 60 pacientes portadores de estenose pulmonar (GEP) e em um de 30 pessoas normais (GN). O GEP foi dividido em dois subgrupos: o de 36 pacientes portadores de estenose pulmonar pura (GEPP) e o de 24 pacientes portadores de estenose pulmonar associada a defeito septal (GEPS). No GN, o valor A/V foi de 1,27 +/- 0,17 (media +/- desvio-padrao), enquanto no gep foi de 1,81 +/- 0,51, com diferenca altamente significativa comparada com o GN (p < 0,0001). No GEPP, o valor foi de 1,88 +/- 0,51, enquanto que no GEPS foi de 1,70 +/- 0,50, mostrando pequena diferenca entre as medias, porem nnao significativa (p < 0,05). Contudo, ambos subgrupos apresentaram uma diferenca altamente significativa comparados ao GN (P < 0,0001). Relacionando-se o GEP com o GN, observou-se que em 63% dos casos A/V estava anormalmente aumentada, sendo que a pressao sistolica de ventriculo direto (PSVO) era maior que 50 mmHg em todos eles. Alem disso, quando a relacao A/V foi maior ou igual a 2,00, a PSVD era maior ou igual a 80,00 mmHg em 95% dos casos.

Importancia da cintilografia com galio (67Ga) em pneumologia. / Importance of the scintigraphy with gallium (67Ga) in pneumology

A caracterizacao, a distribuicao pelos varios orgaos e os mecanismos de captacao do galio sao revistos e, atraves de casos clinicos, e discutida sua importancia em pneumologia, com enfase especial em sarcoidose, alveolite fibrosante, berilliose, pneumonia por P. carinii, carcinoma bronquica e linfomas