Histologic study of the normal human adult soft palate

Detailed information about the tissue components of the soft palate is needed to construct biomechanical models that are functionally useful. Soft palates were removed from 10 adult cadavers, four males and six females. One-half of each palate was further divided into 10 blocks of equal anterior-to-posterior thickness. The face of each block was sectioned and stained using three different stains, thus providing a sample of 300 histologic slides. Each slide was carefully examined and major anatomic characteristics were noted and recorded. The results indicate that a typical adult soft palate consists of several major tissue layers including: (1) the oral aspect, which is glandular with a zone of adipose tissue located somewhat laterally; (2) the two middle layers are muscular with the more inferior layer consisting mainly of transverse levator veli palatini fibers and the overlying longitudinal layer of musculus uvulae fibers; (3) a superoanterior layer consisting of the tensor veli palatini tendon; and (4) a posteroinferior layer consisting of a mixture of tissue that is primarily glandular. The oral mucosa consists of stratified squamous epithelium with a basement membrane that is reinforced with a dense meshwork of elastic fibers. The nasal mucosa consists of pseudostratified ciliated columnar epithelium anteriorly and stratified squamous epithelium posteroinferiorly. The functional implications of these findings are discussed.