Comparative CBCT evaluation of the efficacy of Nd:YAG laser and K3 rotary system in non-surgical root canal retreatment

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.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 P0.05.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).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.