| Popis: |
The authors noted the chage of tastes after cleaning teeth, and researched the change of the taste threshold after cleaning with toothcream and the effects of each component of the toothcream; the effects of surfactants which had been added to toothcream for 20 years or more were also discussed. The results are reported here. 1. The thresholds (special thresholds) of four fundamental tastes of sweet, salty, sour, and bitter in the test group were almost similar to those which were reported 40 years ago. Therefore, the difference in the taste thresholds by age was not observed. It indicated that the surfactants added to toothcream for a long time did not affect the tastes. 2. PH of the saliva not affected by cleaning of teeth. 3. Tastes of sweet and bitter were delayed to be differentiated after cleaning of teeth, but the sour taste was not affected. 4. The tastes which were affected by intraoral stimulation by commercially available "toothcream" and the mixture solution of its components were two tastes of sweet and bitter, while salty and sour tastes were hardly affected. 5. The thresholds were increased or reduced, but generally they were increased in many cases and the threshold concentration reached to 2 to 4 times as high as the original one. 6. The component of "toothcream" which can cause the change of taste thresholds was found to be sodium laurylsulfate. Perfumes strongly affected particularly sweetness and bitterness, and sodium laurylsulfate influenced sweet, salty and bitter tastes; glycerin affected only sweetness. 7. It took 3 to 15 minutes to recover the activity to differentiate sweet, salty, sour and bitter tastes after cleaning teeth with commercially available "toothcream". |
