richly supply the residual ridge and, particularly, the mucoperiosteal tissues. The availability of blood, provided by the number — not the size — of the vessels, encourage rapid healing. The small size of the severed vessels obviates clamping or other methods of retarding blood flow. In a few cases in which the bony ridge has severely resorbed and the tissues have become hypertrophic, the blood supply may be poor. However, usually healing proceeds uneventfully, although at a slower rate, with blood provided principally by the palatal artery, the supply of which rarely diminishes.

The descending palatal artery (7), a terminal branch of the maxillary artery, descends through the pterygopalatine fossa and canal. The main branch (8) exits the bone and passes into the oral cavity through the major palatine foramen as the major palatine artery. One or two smaller branches, the minor palatine arteries (9), leave the bone through the minor palatine foramina to supply the soft palate and upper part of the palatine tonsil, and anastomose with the ascending palatine artery. Also within the pterygopalatine canal, the descending artery gives rise to inferior posterior nasal branches, but these are of minor importance in dental procedures.

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