OBJECTIVE To evaluate the plaque pH responses to sucrose, fructose, xylitol, sorbitol, acesulfame-K, aspartame, and saccharin at equal sweetness levels (equivalent to 10% sucrose) and water using an indwelling plaque pH telemetry system. METHODS Eight adult panelists used each sweetener once in a Latin square study design. Plaque was allowed to accumulate for 3-6 days before each challenge period, and the panelists fasted for 12 hours prior to the 2-minute test rinse. Plaque pH was monitored for a 2-hour period after the rinse exposure. The parameters examined were area of the curves under pH 5.5 (pH X Time), pH changes from baseline, lowest pH attained and time below pH 5.5. RESULTS The the high-intensity sweeteners (aspartame, saccharin and acesulfame-K) and the polyols (sorbitol and xylitol) were all non-acidogenic and were not significantly different from each other while both sucrose and fructose were highly acidogenic.