The IMZ implant system incorporates stress-absorbing elements, such as the intramobile element (IME). There are varying reports regarding the characteristics of the IME however, its effectiveness is still controversial.
In order to evaluate the effectiveness of the stress-absorbing elements under dynamic loading conditions, the stress-transfer characteristics around a single freestanding IMZ implant were investigated with three types of internal elements: an IME made of polyoxymethylene, an intramobile connector (IMC) consisting of a polyoxymethylene head and titanium screw, and a metal element (Metal-E) made of stainless steel.
The vertical (10-kgf) and horizontal (2-kgf) dynamic forces applied to the surface of the superstructure and the strain values around the implant were measured with the strain gauges.
The results were as follows:
1. Under axial dynamic force, the three types of elements had no significant difference in the stresses around a single freestanding implant.
2. Under vertical tilting dynamic forces, a more uniform stress around a single freestanding implant was observed with IME and IMC than Metal-E.
3. Under horizontal dynamic force, a more uniform stress around a single freestanding implant was observed with IME and IMC than Metal-E.
The stress-absorbing elements were significantly effective under the dynamic conditions, while they were not effective under the static conditions.