Pressure transmission across dentine in response to an external pressure: a laboratory study.
OBJECTIVE
To determine whether transducers could provide a convenient method of measuring dentine permeability and to investigate the effects of removal of pulp tissue and perfusion time on the pressure increase across human dentine after low-pressure perfusion.


METHODS
Human premolar teeth that had been stored for 1-2 months were prepared for full crown preparations. The pulp tissue was removed from half the samples and all the coronal segments perfused with saline at 1.3kPa for varying times. An external pressure was then applied and the response within the pulp chambers recorded with transducers.


RESULTS
Extirpation of pulp tissue reduced the rate of rise of pressure inside the pulp chamber by approximately 50%. Perfusion at 1.3kPa for up to 1h had no effect on pressure rise, but 6h of perfusion produced a very significant increase.


CONCLUSIONS
Transducers can provide a relatively simple, convenient and clinically relevant measurement of dentine permeability. For stored coronal segments that have been perfused at physiological pressures, extirpation of pulp tissue and perfusion time have significant effects on pressure transmission across dentine.
Woolley
Graham M
GM
Restorative Dentistry Section, University of Melbourne, 711 Elizabeth Street, Melbourne, Victoria 3000, Australia.
Wilson
Peter R
PR
D000293:Adolescent; D001641:Bicuspid / Q000502:physiology; D002648:Child; D003782:Dental Pulp; D003804:Dentin / Q000502:physiology*; D003806:Dentin Permeability / Q000502:physiology; D006801:Humans; D016014:Linear Models; D010477:Perfusion / Q000379:methods; D011312:Pressure; D013997:Time Factors; D014159:Transducers