Thermal Changes of Root Surface of Anterior Primary Teeth in Pulpectomy with Er:YAG Laser

  • Zahra Bahrololoomi Associate Professor, Department of Pediatric Dentistry, School of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
  • Reza Birang Professor, Department of Periodontics, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran
  • Nasim Chiniforush Researcher, PhD of Laser Dentistry, Laser Research Center of Dentistry (LRCD), Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran
  • Hazhir Yousefshahi Dentistry Student, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran
  • Elnaz Foroughi Assistant Professor, Department of Pediatric Dentistry, School of Dentistry, Arak University of Medical Sciences, Arak, Iran
Lasers, Solid-State, Pulpectomy, Tooth, Deciduous, Thermal Conductivity


Objectives: Successful root treatment depends on elimination of microorganisms from the root canal. Considering incomplete removal of bacteria from the canal by usual methods, lasers have been suggested as a new modality. Despite their anti-bacterial properties, lasers can cause thermal changes. This study assessed the thermal changes of root surface in pulpectomy of primary teeth following the use of Er:YAG laser.

Materials and Methods: Sixty primary anterior teeth were collected and prepared by K-file up to number 50. Then, they were randomly divided into two groups and were irradiated with Er:YAG laser. The first group was irradiated with 1 W laser and the second group with 1.5 W laser. The laser irradiation time was two 10-second cycles with a 2-second interval in both groups. Thermal changes were measured by a thermometer in the apical and coronal areas per second. The results were analyzed by repeated measures ANOVA considering the laser power as between-subject variable.

Results: There was a temperature increase in the coronal and apical areas in use of 1 W power. There was a temperature rise in the coronal and apical areas in use of 1.5 W power. The temperature rise in the apical third was more than that in the coronal third; also, the average temperature rise was more in use of 1.5 W power than 1 W power.

Conclusions: As the average temperature increase was not more than 7°C in any group, this type of laser seems to be suitable for root treatment of primary anterior teeth.


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How to Cite
Bahrololoomi Z, Birang R, Chiniforush N, Yousefshahi H, Foroughi E. Thermal Changes of Root Surface of Anterior Primary Teeth in Pulpectomy with Er:YAG Laser. Front Dent. 15(3):178-186.
Original Article