Different geometric patterns of pacifiers compared on the basis of finite element analysis.

ABSTRACT

AIM: This study was carried out with the purpose to show on a virtual model of oral cavity the mechanical behaviour of different kinds of pacifiers with different pressure levels that can be likened to a condition of rest and deglutition. MATERIALS AND METHODS: Three different types of dummies, orthodontic- (A), cherry- (B) and drop- (C) shaped from an anatomical point of view, were inserted between the palate and the tongue in a virtual system by means of a finite element simulation. The palatal structure was recreated through tridimensional laser scanning, while the tongue structure was reconstructed by a software suitable for reproducing solids. Also the image of the pacifiers was developed by computer-aided scanning and reproduction. Suitable constraints were inserted and high and low pressure levels were exerted on these systems. FEA simulation allowed us to distribute the strain on the palate according to the different geometrical structures of the objects. RESULTS: Dummy A shows a more uniform and wider crosswise stress distribution with also a lesser load on the anterior palatal crest. Dummy B and C, on the contrary, show a more dot-like behaviour inducing a higher stress due to contact on restricted points. CONCLUSION: The characteristics of dummy A, although they have not been clinically investigated yet, seem to be the fittest ones to guarantee the maintenance of the transversal diameters of the premaxilla and reduce the risk of open bite.