results of the following anticalculus tests performed in rats ______________________________________ example iii______________________________________sodium bicarbonate 29 000tetrapotassium pyrophosphate 9 400glycerin 14 500sorbitol 10 solution 20 587peg 8 1 000cmc 0 500sodium fluoride 0 243water 12 000sodium saccharin 0 500sylodent 700 8 000sylox 2 1 000sodium lauryl sulfate 0 500sodium lauroyl sarcosinate 30 1 670flavor 0 900color 0 200______________________________________ this dentifrice was compared with regular crest and tartar control crest in its ability to inhibit calculus formation in rats the animals in the study 30 per cell were treated twice daily five days per week for three weeks they were provided with diet i v 900 throughout the study at the completion of the study the teeth were evaluated for tartar using the method of francis and briner j dent res 48 1185 1195 1969 with the results shown in table ii the results shown are reductions in calculus relative to regular crest the results indicate the potential superiority of the tooth gel of the invention containing 29 sodium bicarbonate over the leading commercial tartar control brand both products contained 5 total pyrophosphate ion however the tooth gel of the invention contained only 0 82 dissolved pyrophosphate ion with the balance present as tetrasodium pyrophosphate decahydrate in control h essentially all of the pyrophosphate was found to be in the dissolved state in a.