An innovative hydroxylapatite canal wall implant underlies a new technique for reconstructing canal wall defects in well-pneumatized "disease-free" mastoid cavities. Previous primary reconstruction involving soft-tissue techniques were not always optimal, depending on the size of the defect. The new hard implant provides lasting canal wall contour, and the implantation technique can be duplicated by other otolaryngologists. Our experience with the implant is described in 11 patients (implant duration 2 to 37 months) using a modification of the technique described by Grote (1986). The implant is biocompatible, being incorporated into surrounding tissues. Indications, contraindications (relative and absolute), and the intraoperative sculpturing method are presented. Long-term and short-term complications are reviewed with suggestions to minimize complications.