Infrared thermographic evaluation of root surface during warm vertical compaction technique

This study aimed to evaluate the effects of heat setting, plugger size, and dentin thickness on the temperature increase at the root surface during warm vertical compaction. A total of 96 mandibular premolars, 36 maxillary, and 36 mandibular central incisors were selected. All root canals were prepared using a 30/07 file. AH Plus sealer and gutta-percha were placed into the canals. In the mandibular premolars, small (40/0.025), medium (50/0.05), and large (60/0.06) pluggers were used, each set at temperatures of 180, 200, 220, and 250°C. For the maxillary and mandibular incisors, a medium-sized plugger was used across all heat settings. Heat was applied to each sample for 3 s, and the maximum temperature was recorded during warm vertical compaction of gutta-percha using an infrared thermal camera. Multiple-linear regression models with dummy variables were utilized to estimate the predictive influence of heat settings, plugger sizes, and dentine thickness on root surface temperature. At 200 and 220°C, the large plugger was associated with a significantly greater temperature increase compared to the small plugger. However, no significant interaction was observed between 250°C setting and pluggers. Interaction between dentin thickness and heat setting indicated that thin dentin was associated with greater temperature increases at 220 and 250°C.