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Effect of effervescent vitamin C preparations on bovine teeth and on some clinical and salivary parameters in man.

Eight effervescent preparations and one chewable vitamin C preparation were tested with regard to dental erosion by immersing bovine tooth specimens for 100 h in 100 ml of the test solutions. For comparison, two effervescent calcium preparations were studied. All the vitamin C products caused distinct erosion and disclosure of dentin in the specimens which could not be found in calcium preparations. Calcium release from the bovine teeth varied from 1.08 to 12.99 micrograms Ca/mm2/h. Softening of the dental tissue assessed as the Vickers hardness units, was most prominent among the specimens where most calcium release was observed. A crossover clinical trial using a test pannel assigned to 1-week periods of excellent vs no mechanical cleaning, and with a consumption of 6.6 times more vitamin C tablets than the recommended daily use, revealed no particular impact of the preparation on a variety of oral health parameters. Except for a slight stimulation of the subjects' salivary flow rate 30 min after consuming the vitamin C, all other differences observed could be explained by the accumulation of plaque during the period without mechanical cleaning. Thus, in patients with normal salivary flow rate a short-term consumption of vitamin C preparations, even in excess, may be regarded as harmless from the dental point of view. However, all the studied preparations are potentially erosive if left in direct contact with the teeth.