Evaluation of root-end cavity preparation using erbium, chromium:yttrium, scandium, gallium, and garnet laser, ultrasonic retrotips, and conventional burs

Aim: To compare root-end cavities prepared with ultrasonics (Group A), with those created by burs in a conventional handpiece (Group B) and erbium, chromium:yttrium, scandium, gallium, and garnet (Er, Cr:YSGG) laser (Group C). Materials and Methods: After root canal instrumentation and filling, apices of 60 single-rooted teeth were resected. Retrograde Class I cavities 3 mm deep were prepared using ultrasonic retro-prep tips (Group A), round burs (Group B), and Er:YSGG laser (Group C). An ultrasonic unit was used with computed tomography-5 retrotip at the frequency of 32 KHz. Laser beam parameters were a pulse of very short duration (100 s), energy of 280 mJ, and repetition rate of 10 Hz. The apical root portion and root-end cavities were replicated and prepared for stereomicroscopic analysis. Results: The degree of chipping associated with the margin of the root-end cavities and the incidence of root face cracks were noted. Marginal chipping of root-end cavities prepared using ultrasonic instrumentation was significantly higher than that produced by bur (P < 0.001) or laser, with laser group showing the least amount of chipping. Conclusion: There was a significant difference between the number of cracks produced by the three methods, with the laser group having the least number of cracks and marginal chipping.