Abstract

OLIVEIRA, Marilin Duarte da Silva  and  OLIVEIRA, Elias PandonorMotcy de. Comparative study between manual and rotatory instrumentation techniques to remove the smear layer. RGO, Rev. gaúch. odontol. (Online) [online]. 2011, vol.59, n.3, pp. 471-476. ISSN 1981-8637.

Objectives To conduct a scanning electron microscopy analysis of the removal of the smear layer from root apical area performed using manual and automated technique of alternate rotation considering the irrigation solutions and time. Methods Forty 11 - 12 mm single roots of human teeth were randomly assigned to four experimental groups (A, B, C, D). The roots assigned to groups A and B were prepared manually. The roots of groups C and D received automated preparation. The roots of groups A and C were irrigated with 1% sodium hypochlorite and groups B and D were irrigated with 17% edetic acid (EDTA) associated with 1% sodium hypochlorite. The preparation time was measured for both techniques. After preparation, the roots were longitudinally sectioned. After processing, they were scanned at a magnification of 1,000x. The images were analysed by two examiners who scored the images according to the level of cleaning of the dentinal tubules. Results Significant difference of 5%, and groups of letters are not statistical difference between the average preparation time. Scores assigned the value of significance less than 0.01%. Conclusion When sodium hypochlorite alone was used, the manual technique produced the best results in removal of the smear layer, whereas the automated technique produced the best results when using the association of sodium hypochlorite with edetic acid as well as with the time of preparation.

Keywords : Smear layer.; Dental pulpcavity.; Endodontics..