Background: The aim of the present study was to compare the efficacy of Nd:YAG laser and K3 rotary system in the non-surgical root canal retreatment.
Methods: Sixty-one rooted human teeth were divided into two groups of 30 after root canal therapy. In groups 1 and 2 root canal retreatments were carried out using K3 rotary system and Nd:YAG laser, respectively. CBCT images were used to evaluate canal transportation and root canal debridement at coronal, middle and apical canal cross-sections. In addition, the time necessary for canal debridement and the temperature on the external root surface were calculated. Mann-Whitney U test was used for statistical analysis of data with SPSS 17 after means ± SD were calculated. Shapiro-Wilk test was used to evaluate normal distribution of data. Statistical significance was defined at P<0.05.
Results: The mean time necessary for the debridement of root canals in the laser group was significantly shorter than that in the K3 group (P=0.001). However, there were no significant differences in external root surface temperatures between the two groups (P=0.17). The coronal third of the canals was cleaner in the laser group significantly (p=0.01). Less canal transportation was seen in the laser group compared to the K3 group, significantly (P=0.04).
Conclusions: Nd:YAG is superior to K3 rotary system in the non-surgical root canal retreatment because it is faster and results in less canal transportation in the middle and apical thirds of the canals.