Cleaning of the root canal using Nd:YAP laser and its effect on the mineral content of the dentin.

Objective: The aim of this study was to compare the efficacy of root canal cleanliness with and without Nd:YAP laser and to assess the effect of the laser on the mineral content of the dentin.

Background data: A high degree of cleanliness of the canal when using the Nd:YAG laser has been shown while the laser is in contact with the canal wall. A new Nd:YAP laser has been studied recently, which is considered to be superior to the Nd:YAG with regard to antibactericidal ability due to its 1.34 micro m wavelength, which is in the infra-red range. This wavelength is absorbed better in water than that of Nd:YAG.

Materials and methods: Fourteen extracted single rooted premplars were divided into two groups. In group 1, canals were cleaned, instrumented, and shaped with K files. In group 2, initial preparation was done using K files and completed with a Nd:YAP laser. Teeth were then split longitudinally and submitted to scanning electron microscopy.

Results: The cleanliness of the laser-treated teeth was significantly greater than teeth treated with K files alone (p < 0.05). No difference in Ca and P content was detected when the use of K files was compared to the use of laser.

Conclusion: It appears that the Nd:YAP laser improves the cleanliness of the root canal. However, since the Nd:YAP laser serves as an addition to K files, its clinical value for replacing conventional root canal instrumentation remains to be determined.