<ORIGINAL ARTICLE>Histologic investigation of tissue surrounding bone in a HA-coated implant supported super structure with and without stress-absorbing elements

The effectiveness of the implant-supported overdentures has been attracted attention for edentulous patients, and a number of studies have been reported. Implant-supported overdentures refer to implant-retained tissue-borne overdentures and it is different from the implant-supported fixed partial dentures recommended by Branemark. In implant-supported overdentures, the functional load may concentrate on implant where there is rigid connection. Loaded implants may cause a resorption of surrounding bone, leading to malfunction, loosing, and the ultimate failure of the implant. The present study reports a stress-absorbing element using a resilient compound designed as the super structure of a two-piece titanium core with hydroxyapatite coated cylinder implants, to avoid stress concentrations, and a histological comparison of the surrounding bone tissue with rigid elements. No notable histological differences were observed in the trabecular patterns by contact microradiography and light microscopy