Sometimes when the conventional endodontic access is not possible, the unconventional approach can save the day.
A clinician should always aim at establishing a straight line access (SLA) in order to properly instrument, irrigate and obturate the canal system. Depending on the initial challenges, establishing a SLA could mean accessing an anterior tooth through its buccal surface [example below], accessing an anterior tooth through its incisal edge, or accessing a molar tooth through its mesial marginal ridge or its MB cusp.
Dr. Mahmoud Ektefaie @ vanendo