Experimental strain analysis of infant, adolescent and adult miniature swine skulls subjected to simulated mastication forces

Abstract

An experimental strain analysis was performed on three miniature swine skulls to obtain a better insight into the mechanism of bone remodelling. An infant, adolescent and adult swine skull were instrumented with electrical resistance foil strain gage rosettes. The skulls were loaded through the muscles of mastication with applied forces proportional to the muscle-masses. Tooth force reactions were obtained at the molar and incisors. Measured strains were converted to principal strains using Mohr's strain circle. The principal strain variation and magnitude was greatest in the infant. less in the adolescent and least in the adult. The strain variation results can be attributed to a negative feedback system modifying a genetically derived bone structure and form. For given masticatory muscle forces, the molar forces were 50–60% greater than incisor forces. The largest strains due to mastication occurred on the side of the skull where chewing takes place.