Abstract
The mastoid process of the temporal bone can become infected with possible serious complications. If the infection does not respond to antibiotics, the infected area must be surgically removed, with the result that a cavity is formed. This cavity must be obliterated before the soft tissues can be closed over the site.
Many biological tissues have been used in attempts to obliterate the mastoid cavity. Fat grafts and diced cartilage have shown less than optimum success because of their tendency to suffer various degrees of resorption. The most popular obliterative technique has been the musculoplasty in which a flap is cut from the temporalis muscle and rotated into the cavity. This method shows a great deal of success, but is a difficult procedure to do since the flap must be provided with adequate vascularity and must be cut to exactly the correct length. Hence this procedure works best for otologic surgeons who have had a great deal of experience in this method.
Various forms of ceramics (either impervious spheres or porous pieces) have been used to obliterate the surgically produced cavity in the feline tympanic bulla. This bulla is a common model for the human mastoid. Since the ceramics must only fill the cavity and no stress is involved in this application, the brittle nature of ceramics is not a factor in their usefulness.
The ceramics are held in place well by the ingrowing soft tissue and hence obliterate the cavity. Porous pieces of alumina seem to be best from the point of view of rapid tissue ingrowth holding them in place faster than the impervious spheres which require tissue to grow around them.
The use of bioceramics to obliterate mastoid cavities would lead to an obliterative procedure in which an otologic surgeon would only have to excavate the infected cavity, fill it with ceramics, and close the site. He would not have to be involved with the tricky business of tailoring muscle flaps or obtaining homologous or autologous tissue.