[Piezo-electric activity of dental tissues]

The appearance of electrical charges on dental samples submitted to 10 daN compression strains was confirmed. In a first series of experiments a correlation was determined between the charges measured and the importance of the organic element at the studied locations. In a second series of measurements carried out on dental specimens after extraction of their organic content there was an almost complete disappearance of the piezoelectric phenomenon. Thus the piezoelectric phenomenon appears essentially in the organic stroma and perhaps also in certain non centro-symmetrical crystals the existence of which has to be demonstrated.