| 摘要 |
PURPOSE: To diagnose the presence of a paradental disease or its progressive situation by measuring at least one sort of gaseous volatile product of a crevice liquid existing in a tooth groove, and comparing the obtained value with a known parameter indicating the presence or progression of the paradental disease. CONSTITUTION: A aqueous liquid sample 10 containing a dissolved gas (for example, oxygen) is accommodated in a measuring chamber 20 which functions also as an inflow chamber. An active electrode 30 and a reference electrode 40 have sensor ends 31 and 41 immersed in this liquid sample 10. These electrodes are connected through conductors 32 and 42 to an external circuit 40 consisting of a power supply 51, voltometer 52, ammeter 53, and switches S1 and S2. The measuring procedure for the dissolved oxygen PO2 in the aqueous sample consists of measuring an open circuit potential having a correlation with a sample pH and measuring the current based upon a negative applied working potential situated in the central part (B-B line) of the oxygen plateau region P1. The oxygen concentration concerning the current can be determined from the current observed in comparison with the reference standard value, corresponding to a proper PO2 curve selected among a group of plateau curves existing in the P1 region. |
