Dentinal and Pulpal Response. V. Application of Pressure to Exposed Dentin

¹ Department of Dental Histopathology, Royal School of Dentistry, Stockholm

The response to pressure on exposed dentin has been studied in four series of experiments. The pressure at which pain was elicited was recorded and the reaction in the dentin and pulp examined histologically. The pressure was applied with air or water at 1-3 kg/sq cm. In three series of experiments the teeth were extracted a few minutes after the pressure had been applied. In one series on contralateral pairs of teeth, one cavity of each pair was subjected to water pressure—3 kg/sq cm for 3 minutes; both cavities were filled with amalgam, and the teeth were extracted after one week.

The results of histological examination indicated that a pressure of 2-3 kg/sq cm, provided that it is not exerted by gas, did not give rise to immediate pulp changes to any appreciable extent. However, water pressure of 2 kg/sq cm for 3 minutes resulted in a marked reduction of the odontoblast layer beneath the cavity through a secondary movement of odontoblast nuclei into the tubules. This pressure might also have been responsible for the slight inflammation observed.

Pain was elicited in most cases with a pressure of 2-3 kg/sq cm. The observation of pain in both this study and the earlier experiments seems to support the theory that the sensitivity of the dentin is dependent on a hydrodynamic or pressure mechanism.

This article has been cited by other articles:

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				J.M. Mumford and A.V. Newton Transduction of Hydrostatic Pressure to Electric Potential in Human Dentin Journal of Dental Research, March 1, 1969; 48(2): 226 - 229. [Abstract] [PDF]