Insertion and removal effects of tooth supported overdentures on retention strength and fatigue resistance of attachment systems: An in vivo study

Over the years, fabrication of an adequately retentive mandibular complete denture has remained a challenge when compared to its maxillary counterpart with an optimum denture bearing foundation.[1] It was the evolution of the concept of tooth-supported overdentures that markedly increased the retention and stability component. With the advent of implant-supported overdentures, the aesthetic, phonetic, and maintenance factors can be dealt with even in those patients with a neuromuscular compromise.[2,3] It is always a justifi able fact that retaining the healthy roots of natural teeth is a better option that placing implants, thereby stressing the importance of understanding various facets of tooth supported overdentures and its clinical applications. Various attachment systems are commercially available but little or no data is available corelating the attachment used and the overdenture support confi guration especially of the tooth supported overdentures. The major problem being the wear of the elastic component, which requires regular replacement. There is no established data available that would help us identify the average life of the components, time-frame of its replacement or repair due to its usage in the oral environment. Lehmann and Arnim[4] stated that during the function, stabilization of the overdenture can occur when the retention forces of attachment systems varied between 5 and 7 N whereas daily insertion and removal, the oral environment can result in the wear and loss of the prosthetic system.