Anesthesia of the hard palate is necessary interventions palate and periodontal procedures, drainage of abscesses and extractions. In most cases the identification of the foramen is made with reference to the second molar. Although this guide is considered unstable because of possible periodontal disease. This study aimed to determine the topography and morphology of the greater palatine canal, and its use for large trunk locks. A sample of 43 skulls was used. Measurements were done with a compass needle points, a caliper and needle 27 g. The landmarks were the anterior nasal spine and later, the tuber of the jaw, the pterygopalatine fossa and cruciform suture. The data were analyzed statistically. The results show a significant difference between the length of the gap the greater palatine foramen and the distance between the tuber of the jaw and the beginning of the suture pterygomaxillary. With this study we can conclude that the gap of the foramen has variable length which requires further criterion for the anesthesia. For the maxillary nerve block via the greater palatine foramen, considerations in facial biotype of the patient should be made.