Conclusion: Although we have shown that malleus handle and mucosal factors were important prognostic factors for hearing, we were unable to show the positive effect of the stapes superstructure on hearing results. The positive effect of the presence of the stapes superstructure on hearing results is closely related to the quality of the mucosa. Objective: The aim of this study was to investigate the impact of ossicular and mucosal factors on hearing in primary canal wall down (CWD) surgery with ossicular chain reconstruction (OCR) performed for extensive acquired cholesteatoma. Patients and methods: A total of 134 adults who had CWD surgery with OCR for extensive acquired cholesteatoma between January 1996 and May 2007 were retrospectively analyzed. Results: The graft insufficiency was 13%, chronic infection without cholesteatoma was 6% and cholesteatoma recurrence was 8% after the first operations. The rate of anatomic failure was 10% after a follow-up period of 46.3 months. In this study, we present the anatomic results for 136 ears and functional results for 135 ears. The hearing gain was significantly higher in the cholesteatoma-only group when compared with the mucosal-cholesteatoma disease group. Forty-three ears (54%) in the cholesteatoma-only group and 23 ears (42%) in the mucosal-cholesteatoma disease group had postoperative ABG within 20 dB. The best hearing results were obtained in Austin group B, while the worst hearing results were evident in Austin group C (p=0.017). Postoperative ABG was within 20 dB in 44% (n=31) of the patients with an intact stapes superstructure, while this ratio was 54% (n=35) when the stapes superstructure was absent.