To present the hearing results of a 5-year longitudinal study in a pediatric population undergoing surgery for extensive cholesteatoma using a canal wall up (CWU) approach with bony obliteration of the mastoid and epitympanic space, with a standard residual rate of 5.8%, a recurrence rate of 2.9%, and all ears waterproof, free of otorrhea and all external ear canals patent and self-cleaning.