Getty Images The review said people were brushing regularly with the charcoal-based products in the hope that they would offer "a low ... charcoal toothpastes and powders were more abrasive ...

Relative Dentin Abrasion or RDA value measures the abrasiveness of a toothpaste. The scale ranges from 0 to over 200: 0 to 70: Low abrasivity, so it is safe for long-term use. 70 to 100 ...

"Toothpaste tablets are often too abrasive for the teeth, [and may] cause more damage than good," she said. Some amount of abrasion is normal for toothpaste, though — that's typically how ...