Current concepts for determining the postpalatal seal in complete dentures.

Purpose: In 2001, a survey of U.S. dental schools was conducted to determine the concepts and techniques used for establishing the postpalatal seal (PPS) in a predoctoral dental curriculum.
Materials and Methods: The questionnaire was mailed to the chairperson of the prosthodontic/restorative departments of 54 U.S. dental schools. Of these, 44 returned the completed survey, resulting in a response rate of 82%.
Results: Results from this survey show that 80% of the schools are teaching a combination of phonation with other methods for locating the vibrating line. The 1 vibrating line concept for establishing the PPS is taught by 80% of schools; 77% of these schools locate the posterior termination of the maxillary denture on the vibrating line. Carving the PPS in the maxillary master cast is taught by 95% of the schools. Most of the schools teach the students to carve the PPS to a depth of 1.0-1.5 mm in the maxillary master cast. Compressibility of the palatal tissues is a consideration during PPS carving for 91% of the schools. The butterfly pattern is the most frequently (75%) described pattern for PPS carving.
Conclusions: There is some variability from school to school on performing the PPS in the maxillary denture, although some trends are evident.