The Effect of Root End Cavity Preparation Using Er,Cr:YSGG Laser, Ultrasonic Retrotip, and Bur on the Apical Microleakage of Retrograde Cavity Filled with MTA Plus

Aim: The sealing ability of the retrograde material is greatly affected by the technique used for root end preparation. Advances in retrograde preparation techniques such as lasers has shown to provide an efficient outcome. The study was to evaluate and compare the effect of various techniques of retrograde cavity preparation on apical microleakage. Materials and Methods: Forty-five single rooted teeth were decoronated. Biomechanical preparation was carried out up to size F2 ProTaper system and obturated. Glass-ionomer cement was used as an access restorative material. The apical root resection was done at 3 mm from the apex at angulation of 90 degrees to the long axis of the root. The allocation of the samples was done into three groups of 15 each. Group A: Retrograde cavities prepared using conventional round bur; Group B: Retrograde cavities prepared using ultrasonic retro preparation diamond tip; and Group C: Retrograde cavities prepared using "Erbium, chromium: yttrium, scandium, gallium, garnet" (Er,Cr:YSGG). The retrograde cavities hence prepared were filled with MTA Plus. Nail varnish was used to coat the samples except at the apical end. Samples were immersed in methylene blue for 24h. Stereomicroscope was used for examination of the sectioned teeth. The data were analyzed using one-way analysis of variance (ANOVA) and post hoc Tukey test. Results: Results showed very highly significant difference between laser and bur (P value = 0.001). Conclusion: Retrograde preparation with Er,Cr:YSGG showed significantly less microleakage when compared to the use of ultrasonic retrotip and burs.