A Follow-up Study of Maxillary Implants Supporting an Overdenture: Clinical and Radiographic Results
Regina Mericske-Stern, Prof Dr Med Dent, Matthias Oetterli, Dr Med Dent, Peter Kiener, Dr Med Dent, Ernö Mericske, Dr Med Dent
Purpose: Studies of maxillary overdentures supported by endosseous implants often show a high implant failure rate. The aim of the present investigation was to evaluate clinically and radiographically non-submerged implants supporting an overdenture in the maxilla. Materials and Methods: Forty-one patients were consecutively admitted for treatment. The standard procedure was to place 4 implants and to mount a U-shaped bar for overdenture connection. When the overdenture was delivered to the patients, peri-implant parameters were recorded and radiographs were taken. All patients were required to follow a maintenance care program. In the context of this study, all patients were clinically examined and the peri-implant parameters were compared. Crestal bone loss was analyzed using linear radiographic measurements. A life table analysis was applied to calculate the cumulative survival rate (CSR). Results: Three implants failed in the early healing phase, and 3 patients lost 6 implants during the loading period. The 5-year CSR of all implants was 94.2%. The peri-implant parameters gave evidence of healthy soft tissues and good oral hygiene. The increases in probing depths and attachment loss were significant (P < .05). The mean marginal crestal bone loss was about 0.7 mm and was statistically significant at mesial and distal sites (P < .001). Discussion: The correlation between clinical attachment loss and crestal bone loss was not significant. Pronounced marginal bone loss was found around some implants. Conclusion: In planned maxillary overdenture treatment, it is possible to achieve a satisfactory survival rate of the implants.