gingiva. Here they provide a cushion primarily for the tongue as it moves against the roof of the mouth. Although the lobules are resilient, the tissues in this region are firm due to the numerous connective tissue fibers that span the submucosa, joining the periosteum to the mucous membrane.

The fatty zone extends posteriorly to meet the glandular zone. The line of demarcation between the two is fairly clear, and begins at approximately the mesial half of the first molar.

Posterior to the fatty zone, covering the remaining surface of the hard palate and extending into the soft palate, are the palatine glands (25). These, too, lie in the submucosa, and form an almost compact layer, with the glands increasing in size and thickness as they move into the soft palate.

The palatine glands secrete saliva through numerous small ducts. As well as their lubricative and digestive functions, the palatine glands also provide a resilient surface for the other oral structures.

The Palatine Velum (Soft Palate)

The soft palate (1), continuing posteriorly from the hard palate (2) and almost as long as it, forms a soft tissue barrier between the oral and nasal cavities. That portion facing the oral cavity is covered by typical, stratified, squamous oral epithelium (3), which continues for a short distance onto the nasal surface, where it is replaced by the pseudostratified, ciliated, columnar epithelium (4) typical of respiratory passages.

The superior portion of the soft palate is composed principally of muscles (5) running in many directions. Inferiorly, it contains mucous-secreting glands (6) that help lubricate the oral cavity and its contents, and contribute to the initial digestion of food. Many of these glands empty via ducts into a small, sharply demarcated depression or pit (7) located immediately behind the hard palate, close to its midline. Often this depression, the palatine foveola of Stieda, is present only unilaterally.