Comparing Warm and Cold Gutta-Percha Techniques for Root Canal Filling: An In Vitro Study

ABSTRACT Gutta-percha is commonly used in endodontic therapy for obturating root canals after cleaning and shaping procedures. Warm and cold gutta-percha techniques are two common methods employed for obturation, each with its own advantages and limitations. Twenty extracted human teeth with single-rooted canals were selected and divided into two groups: warm gutta-percha obturation and cold gutta-percha obturation. In the warm gutta-percha group, gutta-percha was heated to a predetermined temperature using a warm gutta-percha heating device and injected into the root canal using a heated carrier. In the cold gutta-percha group, gutta-percha was applied directly to the root canal without prior heating. Root canal obturation quality was assessed using radiographic imaging to evaluate the presence of voids, completeness of obturation, and adaptation to the canal walls. Micro-computed tomography (micro-CT) analysis was also performed to quantify the volume of obturating material and assess the three-dimensional distribution of gutta-percha within the root canal space. Both warm and cold gutta-percha techniques demonstrated effective obturation of root canals, with comparable outcomes in terms of void formation, completeness of obturation, and adaptation to canal walls. However, micro-CT analysis revealed differences in the volume and distribution of gutta-percha within the root canal space. Warm gutta-percha obturation exhibited more uniform distribution of gutta-percha material and higher volumetric filling compared to cold gutta-percha obturation. Additionally, the warm gutta-percha technique demonstrated superior flowability and adaptation to irregularities within the root canal system. In this in vitro study, warm gutta-percha obturation demonstrated advantages over cold gutta-percha obturation in terms of volumetric filling, distribution within the root canal space, and adaptation to canal irregularities.