Variation in the normal anatomic pattern of the inferior alveolar nerve canal such as bifid or trifid mandibular nerve canal is one of the reasons for local anesthetic failure in dental practice. The present article reports 5 cases of bifid mandibular nerve canal and 1 case of trifid mandibular canal and discusses their diagnostic criteria, radiographic features, and clinical implications in dental practice. The objective of this review is to help clinicians identify bifid and trifid mandibular canals on panoramic radiographs and subsequently use the information in the modification of dental treatment planning. Once the multiple canals are identified, the local anesthetic injection technique, prosthetic design, and surgical procedures can be modified to prevent pain and discomfort during treatment procedures. Keywords: bifid mandibular canal, inferior alveolar nerve, local anesthesia, mandibular canal, panoramic radiograph, trifid mandibular canal