The diluting effect of saliva on the sucrose concentration in different parts of the human mouth after a mouth-rinse with sucrose.

Saliva at four buccal sites [between the upper (UC) and lower (LC) central incisors, and between the upper (UM) and lower (LM) second premolar and first molar], and also whole saliva, was collected from 10 subjects at 0.5, 2.5, 5.5 and 10.5 min after a rinse with 10 ml of 0.3 mol/l sucrose solution. After 0.5 min, unstimulated salivary flow rate was inversely correlated with sucrose concentration in whole saliva (p less than 0.05). Sucrose concentration decreased faster at LC than at other sites. Sucrose dilution at UC and LC was inversely correlated (p less than 0.05) with salivary flow rate at times after 0.5 min. At 10.5 min, the sucrose concentration at all sites was significantly correlated (p less than 0.05) with the salivary flow rate.