The posterior palatal seal. A review.

The posterior palatal seal area is described and its anatomical borders are defined. The methods used to achieve a seal are (1) scraping the cast, (2) a selective loading impression technique, and (3) a physiological impression technique. Each method is described and its problems are discussed. It is believed by the authors that the physiological impression technique using wax requires the least amount of skill and experience to master competently.