[Studies on oral sensation in patients with implant denture. 3. Ability of interdental dimension discrimination]

Interdental dimension discrimination (IDD) ability in 11 patients with implant dentures was compared with that in 10 normal dentate subjects and bridge wearers. Using a 3.0 mm diameter wire as a reference, minimum perception difference between reference wire and test wires were measured at first molar region. In discrimination of thicker wires from reference wire, IDD ability was highest in normal dentate subjects followed by bridge wearers. It was lowest in implant denture wearers. In discrimination of thinner wires from reference wire. IDD ability was highest in bridge wearers followed by normal dentate subjects. It was lowest in implant denture wearers. A so-called "directional specificity", namely, higher IDD ability between thinner wires and reference wire than between thicker wires and reference wire, was recognized in normal dentate subjects and bridge wearers. However, there was no demonstrable directional specificity in implant denture wearers. On analyzing IDD ability in individual patients of implant denture wearers. IDD of both thicker and thinner wires from reference wire were approximately the same in 3 of the patients as those in normal dentate subjects and bridge wearers. In 7 patients, IDD ability of either thicker or thinner wires from reference wire was lower compared to the two other groups. In remaining patient, IDD of both thicker and thinners wire was impaired.