Evaluation of temperature change during antimicrobial photodynamic therapy with two different photosensitizers in dental caries

Introduction: Many attempts have been made in elimination of bacteria in infected and demineralized dentin to not only provide efficient bactericidal potential, but to have minimal damage for tooth structure. The aim of this study was to assess the temperature change during aPDT with ICG and TBO compared with conventional Diode laser irradiation.

Materials and methods: 48 premolar teeth which were selected for this study. A class I cavity was drilled in each teeth, with dimensions of 2mm width, 4mm length and depth of 2.5-3.5mm, providing a dentinal wall of approximately 0.5mm for pulp chamber. Then teeth were randomly allocated in 4 experimental groups (n=12); Group 1: TBO+LED, Group 2: ICG+Diode Laser, Group 3: Diode laser with output power of 0.5W, Group 4: Diode laser with output power of 1W. Thermocouple device was held by experimenter hand and the sensor was in pulp chamber of the teeth. Heat generated during irradiation was reported on LCD screen by NUX Plus software. Repeated measure ANOVA was used in order to compare the temperature before and after laser application. Tukey HSD was used to compare the results between groups.

Results: Temperature was risen for about 0.54±0.05°C for group 1, 1.67±0.14°C for group 2, 4.21±0.83°C for group 3, and 4. 50±0.32°C for group 4. The difference between group 1 & 2, 1 & 3 and 1 & 4 was significant (p<0.0001).

Conclusion: According to results of this study, Diode (with or without photosensitizer- 0.5 and 1W) can be safely used as alternative approach for disinfection after caries removal in thermal point of view.