Modelo BRAN-RS para la enseñanza de la conductometría electrónica sin verificación radiográfica a alumnos de licenciatura: estudio piloto / BRAN-RS model for teaching electronic root canal lenght measurement without X-ray confirmation by undergraduate students: a pilot study

Propósito: demostrar la ejecución de la conductometría electrónica sin verificación radiográfica con el modelo BRAN-RS, por dos alumnas de licenciatura en odontología Material y métodos: Se emplearon dos molares naturales, de los cuales se utilizaron seis conductos permeables (cuatro mesiales y dos distales); el localizador de foramen apical Raypex 6, tipodonto de acrílico y alginato. Los dientes se incluyeron en el espacio de los molares, que se abocardó y rellenó con alginato. Se insertó el clip labial por debajo del tipodonto. Una cavidad de acceso fue realizada en cada molar, se determinó la entrada de los conductos y se amplió con fresa Gates-Glidden número 4. Con el dispositivo Raypex conectado, se introdujo gentilmente en cada conducto una lima tipo K número 15 o 20, cerrándose el circuito con el sujetador de limas. La posición de la lima en el foramen se observó en la pantalla, que se indica por medio de la barra y punto rojos. La lima fue reajustada en las dos primeras barras amarillas y se fi jó con resina fotopolimerizable. Los molares fueron retirados del alginato, se diafanizaron y evaluaron con microscopio clínico a 16X para confi rmar la longitud de trabajo. Resultados: La posición de la lima respecto al foramen apical en los seis conductos fue precisa al 100 por ciento. Conclusión: El modelo BRAN-RS es fácil de realizar, preciso, y puede utilizarse por alumnos de la licenciatura en la práctica preclínica de conductometría.

To demonstrate how two undergraduate students perform electronic root canal measurement without X-ray confi rmation using the BRAN-RS model. Material and methods: Six permeable root canals (4 mesial and 2 distal) from two natural molars; Raypex 6 electronic apex locator; acrylic typodont; and alginate. The teeth were inserted in the molar space, which had been widened and fi lled with alginate. The lip clip was placed below the typodont. An access cavity was made in each molar and the entrance to the root canal located and widened using a number 4 Gates-Glidden drill. Once the Raypex device was connected, a number 15 or 20 K-fi le was gently introduced into each canal and the measurement circuit closed using the fi le clip. The posi-tion of the fi le within the foramen was shown on the screen in the form of a red bar and a red dot. The fi le was readjusted within the fi rst two yellow bars and secured using a light-cured resin. The molars were removed from the alginate, then diaphonized and evaluated under a clinical microscope at 16X magnifi cation to confi rm the working length. Results: In the six root canals, the position of the fi le relative to the apical foramen was 100% accurate. Conclusion: The BRAN-RS model is accurate, easy to perform, and can be used by undergraduate students in the preclinical practice of root canal measurement.

Comparative analysis of the eletronic and radiographic determination of root canal length of primary molars: an ex vivo study

Aim: To evaluate comparatively the radiographic and electronic root canal length determination in primary molars. Methods: 128 canals from 66 primary molars were selected. The root of each tooth was cut open on the occlusal face, and the real tooth length (RTL) was measured and the gold standard working length (WL) was determined by subtracting 1 mm from this measurement. The teeth were then placed in a plastic receptacle holding alginate and saline for the electronic determination of the root length using a Root ZX apex locator. The radiographic determination of the WL was obtained by subtracting 1 mm from the measurement highest cusp to the root apex appearing in the radiography. The data were analyzed statistically by the Chi-square test at a 5% significance level. Results: There was statistically significant difference (p<0.05) between each tested method and the gold standard. The Root ZX apex locator and the radiographic method presented satisfactory results in 75.78% and 54.68% of the cases, respectively. Conclusions: The Root ZX apex locator is a reliable method to determine the WL of primary teeth, since it showed greater accuracy than the radiographic method.

The accuracy of the radiographic method in root canal length measurement / 대한구강악안면방사선학회지

For the successful endodontic treatment, root canal should be cleaned thoroughly by accurate mechanical and chemical canal preparation and sealed completely with canal filling material without damaging the periapical tissues. The accuracy of the root canal length measurement is a prerequisite for the success of the endodontic treatment, and the root canal length is often determined by the standard periapical radiographs and digital tactile sense. In this study, the accuracy and the clinical usefulness of Digora(R), an intraoral digital imaging processor and the conventional standard radiographs were compared by measuring the length from the top of the file to the root apex. 30 single rooted premolars were invested in a uniformly sized blocks and No.25 K-file was inserted into and fixed in each canal. Each block was placed in equal distance and position to satisfy the principle of the bisecting angle and paralleling techniques and Digora(R) system's image and standard periapical radiographs were taken. Each radiograph was examined by 3 different observers by measuring the length from top of the file to the root apex and each data was compared and analyzed. The results were as follows; 1. In the bisecting angle technique, the average difference between the Digora(R) system and standard periapical radiograph was 0.002 mmand the standard deviation was 0.341 mmwhich showed no statistically significant difference between the two systems(p>0.05). Also, in the paralleling technique, the average difference between these two system was 0.007 mmand the standard deviation was 0.323 mmwhich showed no statistically significant difference between the two systems(p>0.05). 2. In Digora(R) system, the average difference between the bisecting angle and paralleling technique was -0.336 mmand the standard deviation was 0.472 mmwhich showed a statistically significant difference between the two techniques(p 3. In Digora(R) system and the standard periapical radiographs, there was a statistically significant difference between the measurement using the bisecting angle technique and the actual length(p0.05). In conclusion, the determination of the root canal length by using the Digora(R) system can give us as good an image as the standard periapical radiograph and using the paralleling technique instead of the bisecting angle technique can give a measurement closer to the actual canal length, thereby contributing to a successful result. Also, considering the advantages of the digital imaging processor such as decreasing the amount of exposure to the patient, immediate use of the image, magnification of image size, control of the contrast and brightness and the ability of storing the image can give us good reason to replace the standard periapical radiographs.