The study of anatomic structures in establishing the posterior seal area for maxillary complete dentures

Abstract

STATEMENT OF PROBLEM: The spatial relationship between the foveae palatinae and vibrating lines varies among individuals; such variability could be related to the contour of the palate. PURPOSE: The purpose of this study was to investigate the relative location of the foveae palatinae and vibrating lines and to determine the correlation between the seal area of the posterior palate and the palatal contour with lateral cephalogram radiography. MATERIAL AND METHODS: Fifty participants were examined. The Valsalva maneuver was used to determine the anterior vibrating line, and the phonation ('ah') method was used to detect the posterior vibrating line. The distance from the anterior to the posterior vibrating line and the distances between the foveae palatinae and the anterior and posterior vibrating lines were measured. A lateral cephalogram was made to trace the hard and soft palate contour, and the angle of the palatal contour was measured with the V-ceph program. Correlation analysis was conducted with statistical software to examine the relation between the distance from the anterior to the posterior vibrating line and the angle of the palatal contour at the junction of the hard and soft palate. RESULTS: The anterior vibrating line was located approximately 2.58 ±1.19 mm anterior to the foveae palatinae, and the posterior vibrating line was located 0.71 ±0.68 mm posterior. A positive correlation was found between the distance from the anterior to the posterior vibrating line in the lateral sagittal plane and the angle of the palatal contour at the junction of the hard and soft palate. Correlation coefficients were 0.495 in the left sagittal plane and 0.560 in the right sagittal plane (P<.05). CONCLUSIONS: Considering their proximity to the posterior vibrating line, the foveae palatinae could be reliable reference points for locating the posterior border of the maxillary denture. The results of this study also suggest that a wider posterior palatal seal area could be obtained if the patient has a gentle palatal contour at the junction of the hard and soft palate.