Of major importance to any form of oral surgery is the path-way of the major palatine artery (10). After this vessel emerges from the pterygopalatine canal posterior to the last molar at the major palatine foramen (11), it passes anteriorly in a groove or notch at the angle where the hard palate meets the alveolar. As it progresses it gives off numerous branches to the mucous membranes and glands of the hard palate and to the gingiva of the palatal surface of the alveolar ridge, where the branches anastomose with those of the anterior and posterior upper alveolar arteries. Anteriorly the major palatine artery ascends through the incisive canal (12) and enters the nasal cavity, where it joins septal branches of the sphenopalatine artery.

The major palatine artery is the largest artery encountered during any form of maxillary implant oral surgery, and the most dangerous by far to sever. Fortunately, it lies in a loose sleeve of connective tissue in the submucosal tissues, and slips easily within its sleeve as the mucoperiosteal tissues are retracted to expose the ridge or lateral borders of the hard palate.

The incision (13) to expose the bone should be confined to the crest of the ridge. If the incision is correctly executed, it should

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