Clinical wear of overdenture ball attachments after 1, 3 and 8 years

Objectives: Implant‐supported overdentures have become the treatment of choice in restoring complete edentulism, but the types of attachment to assure durable retention are a subject of debate. Ball attachments were reported as a simple treatment, but wear of components was responsible for a decrease in retention. The aim of this retrospective study was to measure the wear of the ball abutment or patrix after three different periods of clinical wear. Material and methods: Sixty‐nine specimens of three groups of patrix that were in use for a mean of 12.3 months (group A), 39 months (group B) and 95.6 months (group C) were retrieved from 35 patients and measured on a coordinate measuring machine equipped with a touch trigger probe. Ten unused ball abutments were added as a control (group D). The patrix diameters and any deviation from circularity in different axes were measured. Results: The diameters of groups A, B and C were significantly different from that of group D (control). No statistically significant differences were found between diameter and circularity variations between groups B and C. The maximal amount of diameter reduction was limited to approximately 30 μm, and 90% of diameter loss at the equator due to wear was reached in group B. Conclusion: One, 3 and 8 years of clinical wear reduced significantly the diameters of the ball abutments tested, and the maximal amount of wear was reached after 3 years of clinical use. To cite this article: Fromentin O, Lassauzay C, Nader SA, Feine J, Albuquerque RF Jr. Clinical wear of overdenture ball attachments after 1, 3 and 8 years. Clin. Oral Impl. Res. 22, 2011; 1270–1274. doi: 10.1111/j.1600‐0501.2010.02102.x