G. Landini, IS PERIODONTAL BREAKDOWN A FRACTAL PROCESS - SIMULATIONS USING THE WEIERSTRASS-MANDELBROT FUNCTION, Journal of Periodontal Research, 32(3), 1997, pp. 300-307
This paper introduces a theoretical model of periodontal disease that
is multifactorial, cumulative and produces periodontal breakdown in ''
bursts and remissions''. The simulation is based on the generalization
of the Weierstrass-Mandelbrot function as an integration of a series
of sinusoid fluctuations that facilitate or prevent periodontal breakd
own with different frequencies, amplitudes and phases. The breakdown i
s produced when the integration of the factors reaches a certain thres
hold and is stopped when it is below it. The zeroset of the function (
the set of points of the function in intersection with the time axis)
is a self-similar set that corresponds to the instances when the proce
ss switches between destructive and non-destructive phases, and its fr
actal nature indicates that in theory, bursts of destruction do not ha
ve a characteristic duration size. If the mechanism of periodontal dis
ease has in principle similarities to the model presented, then accura
te site-specific predictions about periodontal destruction may prove a
n unrealizable task.