The Effect of Light-emitting Diode Light Intensities and Duration of Cure on Pulpal Wall Temperature among Different Classes of Teeth.

Abstract

The thermal changes during light curing of resin-based composites (RBCs) are recognized, but there is a lack of information about temperature changes in pulp tissue under different curing protocols, especially during bonding of orthodontic brackets onto the tooth surface. In the present study, pulpal temperature (PT) variation induced by the use of four different light cure intensities and different durations of cure among different classes of teeth was measured. A total of 80 different classes of human extracted teeth (maxillary and mandibular central incisor, lateral incisor, canine, premolar, and molar) were irradiated at the same distances with four visible light curing intensities. Brackets (3M Unitek) were bonded with Transbond XT (3M Unitek, Monrovia, California) adhesive and light cured with a light-emitting diode (LED) light cure unit (LCU) (Bluephase). A J-type thermocouple wire was positioned in the center of the pulp chamber to assess the temperature difference. The results were analyzed with analysis of variance (ANOVA) and the Tukey's honestly significant difference (HSD) test. Light-emitting diode with higher intensity induced significantly higher intra-PT changes than did the LED with lower intensity (p < 0.001). Mandibular central incisors had the highest intra-PT of about 45°C at 3000 mW/cm2, 3 seconds. Maxillary central incisors had the highest intra-PT of about 40°C at 3000 mW/cm2, 3 seconds. Mandibular and maxillary canines and molars had the lowest intra-PT of about 10°C at 800 mW/cm2, 20 seconds. Pulp chamber temperature changes were influenced by the intensity and duration of curing and the anatomy of the tooth (class/type of tooth). S S, Anbarasu P, S SK, et al. The Effect of Light-emitting Diode Light Intensities and Duration of Cure on Pulpal Wall Temperature among Different Classes of Teeth. Int J Clin Pediatr Dent 2024;17(4):467-471.