Unusual anatomy of a maxillary first molar with two palatal canals

A thorough understanding of root and root canal anatomy is imperative for successful root canal treatment. The chemo-mechanical preparation of root canal systems aims to diminish intra-canal bacterial populations, facilitating periapical tissue healing (1-3). However, variability in internal anatomy and overlooked canals are common factors contributing to endodontic treatment failures, particularly in maxillary molars, which often exhibit three roots with diverse canal configurations (4). Among maxillary molars, the mesiobuccal root presents the greatest anatomical variability, with over half of cases featuring two or more canals. Conversely, the palatal root typically demonstrates minimal variability, with a single canal and apical foramen in 99% and a single apical foramen in 98.8% of cases (4,5). Despite the overall low prevalence of anatomical variations in the palatal canal of maxillary molars (<2%), it can reach up to 33% in maxillary first molars and up to 14% in maxillary second molars in certain ethnic groups (1). Neglecting missed canals or incomplete obturations can present significant challenges in endodontic treatment and lead to subsequent failure (5,6).

Detecting anatomical variations beyond the standard 1-1 configuration can be challenging on two-dimensional periapical radiographs. Therefore, precise interpretation of radiographs is crucial for treatment planning, with advanced imaging modalities like CBCT offering valuable insights into complex cases. Nevertheless, experienced endodontic clinicians may overlook a bifurcated palatal canal if they are not aware of anatomical variations. Therefore, utilizing proper magnification and meticulous access cavity preparation is essential for performing successful endodontic treatment.