The Subperiosteal Implant For The Totally Edentulous Mandible

When not enough bone exists in the edentulous mandible for the insertion of four endosteal blade-vent implants, the full subperiosteal implant is the implant choice.

An incision is made from the retromolar pad area on one side of the arch and should continue along the tissue covering the residual crest to the retromolar pad area on the other side (1). In those cases where dehiscence of some or all of the inferior alveolar nerve is expected' then this incision must be carried out lingually along the entire region mesial to both mental foramina (2). With a broad periosteal elevator the tissues are pushed away from, rather than pulled away from the bone, exposing the external oblique ridges," symphysis,b mental foramina' and their corresponding neuro-vascular bundles," mylohyoid ridges,' and all the bone on the lingual anterior surface of the mandible including the genial tubercles' (3) .

The impression is taken either without a tray using heavy silicone or with an Omnivac tray fabricated from an original heavy silicone impression (4) taken of the bone and then used for the support of a rubber base impression, (as described in the previous technique) (4). An interocclusal record of centric relationship is taken with the patient's existing maxillary denture in his mouth, for the fabrication of the temporary acrylic stent (5), and an impression of the upper denture is also taken. The tissues are sutured together, usually with interrupted sutures (6). Five to seven days later, the sutures are removed and ideally three to six weeks after their removal, the implant is inserted. At the same time the implant is fabricated, the metal superstructure as well as

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