Position of the greater palatine foramen: an anatomical study through cone beam computed tomography images

Abstract

The block anesthesia of the greater palatine foramen (GPF) is largely used in minor oral surgeries, periodontics and general dentistry. Furthermore, the area of the GPF serves as a donor of soft tissue graft. So, the aim of this study was to evaluate the position and characteristics of the GPF in Brazilian patients using cone beam computed tomography (CBCT) providing anatomical information for the greater palatine nerve block anesthesia and indicate site to collect palatal donor tissue. Fifty CBCT exams of Brazilian patients with a mean age of 35.8years (27 male/23 female) were evaluated. All patients had erupted first, second and third upper molars. A total of 100 GPF were evaluated bilaterally. The GPFs were assessed regarding position, diameter and distances to the midline maxillary suture (MMS) and to alveolar ridge (AR). Guidelines were drawn in the CBCT axial image depicting all molar interproximal surfaces, bilaterally. The guidelines were located between first, second and third molar and in the center of the second and third, performing five guidelines in each side. These guidelines and the molars were landmarks to assess the GPF anatomic position. From the 100 GPF analyzed, 92 were located in the third molar region (24 male/22 female). The 92 GPF were distributed as 47 in the left side and 45 in the right side. The average GPF diameter and the distance to both the AR and the MMS were 3.1mm; 7.9 and 15.3mm, respectively. Within the limits of this study, we concluded that the in Brazilian patients studied, the GPF location was more closely related to third molar. Therefore, whenever the third molar is erupted, it could be used as landmark for successful GPN block anesthesia. Moreover, harvesting palatal mucosa graft around the third molar should be done cautiously to prevent damage to the GPF vascular-nerve complex.