ABSTRACT
The relation between the roots of the maxillary molars, premolars and the sinus has been studied by different authors. The roots of the maxillary first and second molars are in intimate relation to the floor of the maxillary sinus in 40% of cases
During periapical surgery of the maxillary molars and premolars it is possible to find the same complications as in any apicoectomy, including for example damage to a neighbouring tooth
The specific considerations applicable to these teeth are,careful aperture of the maxillary sinus wall or floor; avoidance of sinus membrane perforation; and care to prevent the introduction of foreign bodies within the maxillary sinus. Surgical endodontic success rates have dramatically improved over the years with the developments of newer retrofilling materials and the use of the ultrasonic preparation. A clinical case of apical surgery on a maxillary molar through the maxillarysinus is presented, usinga sinus lift procedureand retrofilling with MTA