Looking at the loading to failure after cyclic loading to evaluate the residual stability of the reconstructions, the result showed again a trend for better outcomes in terms of maximal load, yield load, stiffness and displacement for jail technique (Table 3).
In rats fed a low protein diet, maximal load and stiffness showed a trend to a decrease but it was not statistically significant after cyclic loading (Table 2).
Typical load/deflection curves with both the elastic (linear) and plastic components separated by the yielding point as described by Burstein et al. [ 17] were obtained, enabling graphic determination of the following mechanical properties: maximal load, bone stiffness, and energy at failure.
Similarly, in the osteoporotic bone model there were no significant differences between the constructs regarding cycles to failure, maximal load or overall stiffness.
Maximal load (LMAX (N)), stiffness (slope of the elastic part of the curve (N/mm)), yield point (L Y, point separating the elastic part and the plastic part of the curve (N)), postyield load (maximal load (LMAX) minus yield point load (L Y ) (N)), and postyield displacement (mm) were directly obtained from the load-deflection curve and automatically calculated.
Table 6 Summary of fatigue failure tests: maximal load, vertical & lateral stiffness, number of cycles (all values prior to failure) and failure types.
Stiffness, maximal load to failure, and energy to failure were computed from the resulting force displacement curves.
The following values were obtained: maximal load, n = 15; stiffness, n = 254; plastic energy, n = 8; postyield load, n = 5; postyield deflection, n = 7.
In rats fed a normal protein diet, mechanical properties were almost unaffected by cyclic loading (Table 2) and maximal load to failure and stiffness remained unchanged.
