RESUMO
The possibility of a three rooted maxillary second premolar is extremely rare; diagnosis and treatment of such cases is challenging especially for undergraduate dental students. The aim of this report is to present a root canal treatment of a very rare case of a three rooted upper maxillary second premolar tooth done by an undergraduate dental student. The tooth was diagnosed as acute irreversible pulpitis. Visually the tooth morphologically looked as a normal premolar but radiographically revealed anatomical variations of three roots. Access cavity was opened carefully; three canals were detected, negotiated, biomechanically prepared and obturated by cold gutta percha lateral condensation technique. The tooth is now completely asymptomatic for almost five months and will be both clinically and radiographicaly monitored bimonthly. A correct radiographic and clinical examination based on knowledge of anatomical variation of this tooth is necessary for successful treatment and better prognosis. Under direct supervision, undergraduate clinical students can perform root canal treatment of difficult cases.