Dens invaginatus is a developmental malformation, in which there is an infolding of enamel into dentine. These infolds represent stagnation sites for bacteria and can predispose to dental caries. The carious infection can spread via enamel and dentine to contaminate the pulp and cause soft tissue necrosis. The altered and sometimes complex anatomy of affected teeth can make endodontic management challenging. Early diagnosis is therefore essential as prophylactic treatment of the dens can prevent degeneration and pulpal necrosis. The aim of this article is to review the aetiology, classification, diagnosis and management of teeth affected with dens invaginatus. Emphasis will be placed on describing the clinical features of this anomaly. Treatment options, management strategies and the challenges faced in managing this condition will be discussed.