Perinatal stress and increased fluctuating asymmetry of dental calcium in the laboratory rat.

Recent studies have consistently reported an increased magnitude of fluctuating dental, long bone, and membranous bone asymmetry as a function of perinatal stress. The present study was designed to test the hypothesis that increases in the fluctuating asymmetry of calcium may be related to the metric changes in these calcium-dependent systems. Pregnant rats were exposed to noise stress from conception through weaning. Bilateral lower first molars were extracted from the neonates, and calcium levels were determined using a standard atomic absorption technique. Levels of fluctuating asymmetry of calcium were found to be significantly increased (p less than .01) in the audiogenic noise-stressed group compared to unstressed, normal controls. These results follow the pattern reported earlier for metric analysis of the dentition and support a stress-induced calcium-transport-disruption hypothesis.