There are cases when we need to analyze the treatment alternatives taking into account several factors. This patient was referred by a colleague after an attempt to access the calcified root canal of tooth 42. After clinical examination we considered the use of an access guide unwise, due to the size of the tooth, very small and delicate, and because there was already wear on the crown. The chosen treatment was then the sealing of the coronal space with MTA and paraendodontic surgery and backpreparation and obturation also with MTA.