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Effects of diode laser bleaching and conventional LED bleaching on pulpal temperature using pulp microcirculation
Runal Goutam Sarkar1, Shruti Bhandary2
13 Year Postgraduate, Department of Conservative Dentistry and Endodontics, AJ Institute of Dental Sciences, Mangalore, Karnataka, India.
Background:
The activation of a bleaching agent by thermocatalytic technique which uses heat source as a catalyst agent in the decomposition of bleaching agent causes bleaching of tooth. Destructive effects to the pulp due to temperature rise during bleaching procedure have been described. An intrapulpal temperature increase of 5.5°C is regarded as the threshold value, which should not be exceeded to avoid irreversible pulp damage. In light-activated bleaching, there is great concern about the heat generated by the light source, which may cause pulp necrosis. Hence, this study focuses on the change in pulpal temperature with diode lasers and LED light-activated bleaching.
Aim Of The Study:
The aim of this study was to compare the change in pulpal temperature produced by diode laser and LED light-activated bleaching.
Methodology:
Human-extracted teeth were collected. The specimens were divided into two groups based on the light activation method. The bleaching agent (Pola office) was applied of a thickness of 1 mm. The light source tip was kept at a distance of 5 mm from the bleaching gel applied on the tooth. Bleaching was performed using two light sources: a 980 nm diode laser (Gigaa Laser CHEESE II) and a 780 nm blue LED (Woodpecker Mini-S). For both methods, the bleaching gel was activated in three 30-second cycles, with a 10-second interval between each cycle to allow for cooling and minimize pulpal temperature rise. Temperature change was measured using pulp microcirculation model. Comparison between two groups was done by Student's unpaired t-test. Chi-square test was used for qualitative data.
Results:
Pulp temperature change in LED-activated bleaching was 3.73 ± 1.07 and in diode laser activation 1.285 ± 0.357. For both the groups, the temperature increase was less than the threshold value of 5.5°C, but the difference between the groups was statistically significant.
Conclusion:
The pulp temperature change in LED light bleaching is more than in diode laser-activated bleaching. Both may not have any deleterious effect on pulp.
