Anatomical variations of the dental root morphology may lead to endodontic treatment failure. Knowledge of root morphology and possible anatomical variations may ensure proper endodontic treatment and long-term success. The present study describes the case of a three-rooted maxillary right first premolar with two buccal roots and one palatal root, each of them having one canal, diagnosed with symptomatic irreversible pulpitis. The treatment was applied according to traditional procedures, and the post-therapeutic evolution was favorable without any further complications.