The use of demineralized bone matrix for mastoid cavity obliteration.

Abstract

To evaluate the use of demineralized bone matrix as a graft material for mastoid cavity obliteration in the treatment and prevention of problematic mastoid cavities. The study is a retrospective review of patients identified using a computerized otology database. Tertiary care referral center. Patients were included in this study if they underwent mastoid obliteration using demineralized bone matrix. Mastoid obliteration was performed for revision of a problematic mastoid cavity (n = 8) or primarily after canal wall down mastoidectomy for recurrent cholesteatoma (n = 3). Data were collected to evaluate the ability to achieve a dry ear canal. Postoperative healing time and hearing results were also assessed. A dry ear canal was achieved in all patients with a follow-up of 6 to 20 months (average, 14.5 mo). Eight patients (73%) had a well-healed, dry ear canal by their first postoperative visit (9 wk). One patient required 12.5 weeks to heal. Two patients (18%) had more prolonged granulation at the ear canal incision, which resolved in 17 and 28 weeks, respectively. The average preoperative pure-tone average air-bone gap was 47 +/- 14.9 dB (mean +/- SD), compared with postoperative values of 27.6 +/- 12.8 dB (p = 0.0033; paired t test). This represents an average pure-tone average air-bone gap closure of 20 dB. The use of demineralized bone matrix as a graft extender in mastoid obliteration allowed creation of a dry, smooth-contoured canal in all patients studied. A significant improvement in hearing was also obtained. Demineralized bone matrix is an acceptable graft alternative for mastoid obliteration.