Dental implants can be used to support a wide range of fixed and removable prostheses. When bilateral edentulous areas are located posterior to the remaining mandibular natural teeth, fixed implant partial prostheses are preferred over removable partial dentures (RPDs). However, such a prosthetic option is not always possible because of the patient’s financial status or compromised regional bone anatomy that usually requires extensive bone grafting procedures, making the distal extension RPD (Kennedy Class I) a valid treatment alternative.1-4 The common complaints associated with the distal extension RPD are lack of stability, minimal retention, unaesthetic appearance of the clasp(s), and discomfort upon loading.5 To overcome such problems, some authors have suggested the placement of implants into the distal portion of the posterior alveolar ridges with the assistance of healing abutments for support and/or resilient attachment systems for retention, when possible.6-14
The first treatment step consisted of extractions of the second mandibular left premolar and second mandibular left molar with the immediate delivery of an interim distal extension mandibular partial denture using standard procedures. The interim partial denture was adjusted several times with a soft reline material (Coe-Soft [GC America]) during the healing and treatment phases. Three months later, 2-root form endosseous implants (NT Osseotite 4 x 10 mm and 4 x 8.5 mm [Biomet 3i]) were placed at the second molar region bilaterally into the mandibular alveolar ridge. After 2 months of healing, the first left mandibular premolar and the right mandibular canine were prepared and provisionalized using methyl methacrylate acrylic resin (Jet Lang [Lang Dental Manufacturing]) for full-coverage PFM restorations. The right mandibular canine developed irreversible pulpitis after being prepared and was subsequently treated by endodontic procedures and a fiber post (RelyX Fiber Post System [3M ESPE]).