Subperiosteal implants 559

Fig. 12-70. A, The design of the palatal portion of the subperiosteal maxillary implant must be as broad as possible (Linkow). B, The peripheral borders should end close to the base of the anterior nasal spine, extend high into the canine eminence and slightly below the infraorbital canals, and extend further distally along the zygomatic arch and along the lateral wall of the pterygoid plate.

Fig. 12-71. An incision is made along the crest of the ridge from maxillary tuberosity to maxillary tuberosity. Some-times a vertical accessory incision is made; this can be seen in the anterior region above the primary incision.

Fig. 12-72. The fibromucosal tissue on the labial and buccal aspect is retracted to expose the base of the anterior nasal spine as well as the canine eminence, zygomatic arch, and pterygoid process. The palatal tissue is retracted to expose the entire hard palate, and sometimes the posterior nasal spine and greater and lesser palatine foramina.