Thanks for the advice. Although I haven't suffered a re-occurance of AC for some time, I bought the anti-cavity Crest and tested it against the all-in-one "Pro-Health" Crest. After creating foam during brushing, I brushed the foam of the pro-health on my lips and did notice it was slightly more stingy than the anti-cavity Crest. Could be my mind was playing tricks on me but to hedge I'm using the anti-cavity Crest for now on. Thanks!