apical seal by low temperature thermoplasticized injected gutta percha using sealer and vent versus thermoplasticized injected guttapercha without a vent and lateral condensation techniques

This in-vitro study used the dye penetration to test an idea of filling the root canals by thermoplasticized injected gutta-percha in the presence of vent to allow for the escape of the trapped air at the apical 1/3 during injection of softened gutta-percha. A total of 45 human extracted single rooted teeth were used, crowns were cut-off to facilitate accessibility and instrumentation of the root canals. Irrigation of the canals is performed during and after preparation by sodium hypochlorite 5.25%, and all spicemens were kept moist all the time by immersion in normal saline. Teeth were randomly divided into three equal groups each of 15 roots. The first group was filled by lateral condensation technique with sealer, the second group was filled by the low temperature thermoplasticized injected gutta-percha technique with sealer and a vent and the third group was filled using low temperature thermoplasticized gutta-percha technique with sealer but without using vent. Data obtained and statistically were compared, there were no significant differences between groups at 5% level except in-between lateral condensation technique and low temperature injected gutta-percha technique with vent which showed a higher mean day leakage score. From the results obtained, reached a conclusion that, lateral condensation technique still the acceptable one. Further investigatios were needed to correct the technique of using the vent and this may be correct the results

electrochemical technique to study sealability of five root canal sealers

An in-vitro study was undertaken to investigate the sealing ability andleakage of five different commercial endodontic sealers by an electrochemicaltechnique. The roots of freshly extracted single rooted teeth were selectedand the root canals were biomechanically prepared. The roots were dividedinto five groups, six roots for each group. For group VI, only two roots wereused as positive control with no gutta-percha and no sealer. The degree ofmicroleakage was tested over a period of 30 days by an electrochemicaltechnique, depending on the flow of an electric current between two pieces ofmetal immersed in an electrolyte. The magnitude of the followed current wasdirectly proportional to the degree of the leakage. The study concluded that the large variation in leakage currents in case of positive controls can be attributed to the variation in root surfaces. There is a variation of leakage within the different five root canal sealers not only due to the different physical properties of the root canal sealers but also due to the variation between teeth roots