This article presents two cases of detection and management of four-rooted mandibular first molars. The occurrence of four-rooted mandibular first molars is very rare and the reported incidence is less than 1%. The cases were managed using radiographs taken from different planes (otherwise, the distolingual root of the teeth would have been missed). The contralateral side also showed the same morphological variation. Keywords: anatomical variation, distolingual root, mandibular first molar, radiographic interpretation