Toothpaste abrasiveness index
Be aware of RDA values for brushing your teeth without damage to gums and/or enamel
In addition to toothbrushes with overly hard bristles and too vigorous brushing, another "hard" factor can damage enamel and gums: abrasive toothpastes and powders, including "natural" ones.
This is another reason why Healing Teeth Naturally recommends avoiding commercial toothpastes and going for time-honoured inexpensive alternatives such as baking soda (which contrary to popular misconception is actually the least abrasive tooth cleaner on the market) - or simply water or dry brushing - instead.
Virtually any toothpaste and powders on the market contain abrasive particles (i.e. particles which are not water-soluble) including aluminium hydroxide, calcium or magnesium carbonate, silicates and others.
Such "scrubbing" compounds are added to help remove plaque and stains during brushing, and it's their quantity, particulate size and hardness which determine the degree of abrasiveness of a toothpaste.
To measure a toothpaste's abrasiveness, scientists use the so-called RDA index (from radioactive dentin abrasion or relative dentin abrasion), with higher values indicating increasingly higher abrasiveness.
The more abrasive power, of course, the more likely enamel erosion which can easily open the way to tooth decay - it's typically whitening toothpastes which top the list concerning abrasiveness while toothpastes formulated for sensitive teeth tend to be at the bottom.
While test results have somewhat varied between labs, the following listing (in ascending order) gives an idea of the abrasiveness of commonly used toothpastes. Note that ADA and other official bodies rank values from 0 – 70 as low abrasive, 70 – 100 as medium abrasive, 100 – 150 as highly abrasive and 150 – 250 as the harmful limit.
Regarding the use of calcium carbonate frequently used in tooth powders: On the Mohs scale of mineral hardness (running from 1 to 10), dentin ranks 3, enamel 5 and chalk (calcium carbonate) 3. So it seems unless you have teeth where the dentin is exposed or excessively soft enamel (visible for instance from blunted edges on the incisors), calcium carbonate should be fine.
Toothpaste / tooth powder RDA values (abrasiveness index)
4 brushing teeth with water
7 baking soda / bicarbonate of soda (sodium bicarbonate, NaHCO3)
8 Arm & Hammer Tooth Powder
15 Weleda Salt Toothpaste
30 Elmex Sensitive Plus
35 Arm & Hammer Dental Care
42 Arm & Hammer Advance Whitening / Peroxide
44 Squiggle Enamel Saver
48 Arm & Hammer Dental Care Sensitive
49 Tom's of Maine Sensitive
49-52 Arm & Hammer Peroxicare Regular
51 Crest with Scope
53 Rembrandt Original, Closys
57 Tom's of Maine Children's
60 Biotene Gel
63 Rembrandt Mint
68 Colgate Regular
70 Colgate Total, Arm & Hammer Advance White Sensitive, Colgate 2-in-1 Fresh Mint
80 AIM, Close-Up, Biotene Paste with Fluoride
83 Colgate Sensitive Max Strength, Tooth and Gum Care
87 Nature's Gate
91 Aquafresh Sensitive
93 Tom's of Maine Regular
94 Rembrandt Plus
95 Crest Regular
97 Oxyfresh Powder
101 Natural White
104 Sensodyne Extra Whitening
106 Colgate Platinum, Arm & Hammer Advance White
107 Crest Sensitivity
110 Colgate Herbal, Amway Glister
113 Aquafresh Whitening
117 Arm & Hammer Advance White Gel, Arm & Hammer Sensation Tartar Control
120 Close-Up with Baking Soda
124 Colgate Whitening
130 Crest Extra Whitening
133 Ultra Brite
144 Crest Multicare Whitening
145 Ultra Brite Advanced Whitening Formula, Colgate Baking Soda Whitening
155 Crest Rejuvenating Effects
165 Colgate Tartar Control
168 Arm & Hammer Dental Care PM Fresh Mint
175 Colgate Luminous
176 Nature's Gate Paste
160-190 Crest Pro Health Formulas
200 Colgate 2-in-1 Tartar Control / White
As you can see, the winner is: baking soda! Sodium bicarbonate is not only the gentlest, least abrasive substance one could use (apart from water) but it also removes stains, whitens teeth, raises the saliva pH and kills germs involved in tooth decay and gum disease.
1 Should you (still) use toothpaste and yours is not listed here, you can find out its RDA by contacting the manufacturer such as via the consumer contact information printed on the package.
2 Source of listing: http://satyen.com/toothpastes.shtml et al.
3 More at Baking soda helps teeth & gums.