she is the sort of grocery shopper who must examine each of the 14 varieties of colgate toothpaste and the 12 varieties of crest and the three types of toms of maine , inspecting minutely their claims of whitening power , tartar removal , bacterial massacre , gentleness , sparkle-enhancing properties , naturalness , and of course price per ounce before making her final selection or , sometimes , rejecting all of them and threatening in outraged tones to brush her teeth solely with baking soda from now on .