Alveolar plate fenestrations and dehiscences of the human skull.

M ucogingival surgical procedures require the dentist to have a precise knowledge of both normal and unusua1 anatomic features of the aIveolar process. Fenestrations (Fig. 1) and dehiscences (Fig. 2) of the alveolar plate of bone are often detected only when mucogingival surgical procedures are performed. Such bony defects are probably the result of a slow, progressive absorption of an already existing thin plate of bone covering a prominent tooth ro0t.l Bone of this type usualIy lacks a supporting layer of bone marrow between the outer labial plate of compact bone and the alveolar bone proper and depends on periosteum and periodontal connective tissue for adequate nourishment and blood supply. Therefore, stripping of the periosteum during mucogingival surgery will encourage even further resorption of the thin overlying plate of bone, since bone absorption is greater than bone deposition after surgical intervention.” Since it is difficult to predict with certainty when fenestrations or dehiscences may be encountered during mucogingival surgery, it would be helpful to the dentist who performs periodontal surgery to know which teeth are most often associated with such bony defects. By inspecting dry human skull specimens, we can derive some knowledge of the incidence and distribution of fenestrations and dehiscences in the human skull.