Three-year Follow-up of Immediately Loaded Implants in the Edentulous Atrophic Maxilla: A Study in Patients with Poor Bone Quantity and Quality
Andreas Thor, DDS, PhD/Karl Ekstrand, DDS, MS/Russell A. Baer, DDS/Joseph A. Toljanic, DDS
Purpose: Immediate loading of implants in the edentulous maxilla has previously been successfully performed and reported. Severe resorption of the maxillary alveolar crest presents a more demanding situation for the restorative team. Thus, it would be valuable to assess outcomes for this immediate loading treatment protocol in subjects with marked maxillary alveolar crest atrophy. This study evaluated the 3-year results of dental implants that were immediately restored with provisional fixed prostheses in atrophic maxillae without previous augmentation. Materials and Methods: Two centers enrolled subjects with resorbed edentulous maxillae (Lekholm and Zarb quality 3 or 4 and quantity C, D, or E). Six implants were placed in each subject and restored with screw-retained fixed provisionals within 24 hours. Impressions were taken for definitive restorations, which were placed 20 to 24 weeks later. Radiographs were used to analyze marginal bone level changes throughout the study. Results: Fifty-one patients received 306 implants. Forty-five patients remained in the study at the 3-year follow-up visit and successfully used their definitive prostheses. Sixty-two percent of the implants were placed in bone quantity C and quality 3 or 4, and 38% were placed in quantity D and quality 3 or 4 bone. Thirteen implants in six subjects were lost, resulting in a cumulative survival rate of 96% after 3 years. The mean marginal bone loss during the first year was –0.4 ± 0.8 mm (255 implants); at 3 years it was –0.6 ± 1.1 mm (253 implants). Conclusion: Data from the first 3 years of this study revealed good clinical outcomes. Careful selection of patients and planning by the restorative team can enable successful treatment outcomes for patients presenting with marked resorption of the edentulous maxilla.