<title>Abstract</title> Background This retrospective study aims to characterise the root canal morphology of maxillary and mandibular molars using cone-beam computed tomography (CBCT). The number of roots and canal configurations were evaluated using both the Vertucci and Benjamı´n Brisen˜ o Marroquı´n classification systems. Methods Total of 1084 second molar images (523 upper; 266 right and 257 left sides &amp; 561 lower; 285 right and 276 left sides) were obtained from 320 CBCT scans that were analysed. CBCT imaging provided superior visualisation of root canal anatomy compared to periapical radiography. The findings revealed diverse root canal configurations, with variations observed even within the same population. Statistical analyses, including the chi-squared test, were used to assess correlations between root number and demographic variables such as age and sex. Results According to Benjamı´n Brisen˜ o Marroquı´n classification system, the most common configuration for upper right three-rooted teeth mesial root was ³17²⁻¹ (n:66, 35.7%), for distal root was ³17¹ (n:169, 91.4%), and for palatal root was ³17¹ (n:165, 89.2%). Additionally, the most common configuration for upper left three-rooted teeth mesial root was ³27¹ (n:50, 28.4%), for distal root was ³27¹ (n:160, 90.9%), and for palatal root was ³27¹ (n:158, 89.8%). In lower left molars, the most common configuration in the two-rooted teeth mesial root was ²37² (n:114, 49.4%), and for the distal root was ²37¹ (n:170, 73.6%). For lower right the most common configuration for two-rooted teeth mesial root was ²47² (n:125, 52.5%), and for distal root was ²47¹ (n:173, 72.7%)( p &lt; 0.05). Conclusion Due to highly variable morphological features observed in the upper- and lower-second molars of the Turkish subpopulation, CBCT is strongly recommended on a case-by-case basis. The results revealed extensive variations in root canal morphology.