Evaluation of Effectiveness of Two Different Endodontic Retreatment Systems in Removal of Gutta-percha: An in vitro Study

AIM

To determine the effectiveness of two different endodontic retreatment systems for the removal of laterally compacted gutta-percha (GP).

MATERIALS AND METHODS

Sixty-three freshly extracted human maxillary central incisors were used for the study. The teeth were instrumented with K-flex files and obturated using lateral condensation technique with GP and AH Plus sealer. The teeth were divided into three retreatment groups, each group consisting of 21 teeth. Group I: D-RaCe desobturation files (D-RaCe); group II: ProTaper Universal retreatment files (PTUR); group III: Hedstrom files (H-file). After removal of GP, the teeth were split longitudinally and divided into three equal parts: Cervical, middle, and apical third. The middle and apical thirds of all root halves were examined using scanning electron microscope (SEM). The total surface area covered by the residual debris was evaluated using Motic Image plus 2.0 software. Statistical analysis was done by one-way analysis of variance (ANOVA) test with a p-value <0.05 used to determine significance and Tukey's multiple post hoc tests used for comparison between the groups, and 't' test was done for comparison between the thirds within the same group.

RESULTS

The PTUR retreatment files showed overall better performance compared with D-RaCe files and H-files. The PTUR files performed better at middle third compared with others. The PTUR files and D-RaCe files performed equally at apical third better than H-files.

CONCLUSION

ProTaper retreatment files are better compared with D-RaCe files and H-files for the retreatment of the previously endodontically treated teeth.

CLINICAL SIGNIFICANCE

Highest efficacy for the removal of GP was shown by ProTaper Universal System followed by D-RaCe and H-file.

Comparative evaluation of the efficiency of four ceramic finishing systems

AIM

To compare the effect of four different finishing systems and diamond paste on ceramic roughness with the objectives of evaluating the roughness of ceramic surface of prepared specimens after abrasion, finishing and polishing.

MATERIALS & METHODS

A total of 50 test specimens were fabricated in the form of discs of diameter 13mm and 0.6mm thickness. Test specimens were then randomly distributed into five groups of 10 and coded. All the test specimens were then abraded with 125μm diamond in unidirectional motion to create surface roughness that will simulate occlusal or incisal correction. The values were recorded and the specimens were then finished using the various finishing systems. multiple range tests by Duncan's procedure. One way Anova was used to calculate the p-value Results:After fini shing, the Ra,Rq,Rz and Rt values showed a tendency to decline to levels much inferior to the values obtained after the preparation of the specimens. Ra values of group III specimens were slightly higher and the increase was significant. The highest Rt value [5.29] obtained after polishing is below the lowest roughness values [7.42] obtained after finishing the specimens.

CONCLUSIONS

Finishing and polishing procedures have a significant role in reducing the roughness of ceramics.Following abrasion with diamond point to simulate clinical adjustment the roughness values doubled when compared to the initial reading.Ra, Rq,Rz and Rt values suggest that Sof lex is the most efficient of all the systems tested followed by auto glazing.After the final diamond paste polishing, sof lex group specimens showed the best finish and auto glazed specimens showed a value almost as equal to the so flex group. How to cite this article: Aravind P, Razak PA, Francis PG, Issac JK, Shanoj RP, Sasikumar TP. Comparative Evaluation of the Efficiency of Four Ceramics Finishing Systems. J Int Oral Health 2013; 5(5):59-64.