Toothpastes erode our teeth. There is a scale that helps us to know how much.
A recurring question when we go to the Oscar Gallo dental clinic is what type of toothbrush and toothpaste to use.
Tooth erosion is the loss of tooth enamel caused by acid attack. Enamel is the hard, protective layer of the tooth without nerve endings, which protects the sensitive dentin underneath. When the enamel is worn away, the dentin underneath is exposed, which can cause pain and sensitivity.
Erosion often appears as gaps in the teeth and general wear of the tooth surface and biting edges. This can expose the dentin underneath, which is a darker, yellower color than the enamel. Because dentin has nerve endings, your teeth may also be more sensitive to heat and cold, or to acidic foods and drinks.
Although tooth enamel is the hardest substance in the body, the dentin underneath can be exposed, for example, by wear of the enamel itself or gingival recession. Because of concerns about abrasion of these tissues, the effect of dentifrice abrasives on these tooth structures has been investigated and monitored for decades.
To help quantify the abrasiveness of dentifrices, a standardized scale called Relative Dentin Abrasiveness (RDA) was established. This scale assigns toothpastes an abrasiveness value, relative to a standard reference abrasive that is arbitrarily given an RDA value of 100. All toothpastes at or below 2.5 times the reference value, or 250 RDA, are considered safe and effective. In fact, clinical evidence supports that lifetime use of proper brushing technique with a toothbrush and toothpaste at or below 250 RDA produces limited dentin wear and virtually no enamel wear.
The Mohs hardness (Mohs Hardness) of dentin is 2.5, the Mohs hardness of sodium bicarbonate (NaHCo3) is 2.5. The RDA value of sodium bicarbonate is 7. That means that any toothpaste that has an RDA value greater than 7 has the potential to reduce dentin. The Mohs hardness of toothbrush bristles is 2.5. In addition, research shows that 50% of the damage occurs in the first 20 seconds of brushing.
The RDA test method and upper limit of 250 have been adopted by the American National Standards Institute / American Dental Association (ANSI / ADA).
These are RDA values for common toothpaste:
- 0-70 = low abrasive
- 70-100 = medium abrasive
- 100-250 = highly abrasive
With all this we can organize different toothpastes according to their RDA abrasiveness.
- Elmex Sensitive Plus (30)
- Sensodyne Pro-Enamel (34)
- Rembrandt Original (53)
- Clinpro (62)
- Colgate Classic (65)
- Colgate Total (70)
- Rembrandt Plus (94)
- Colgate Optic White (100)
- Sensodyne Whitening (110)
- Oral B ProHealth (140)
- Colgate Whitening (140)
- Oral B Whitening (200)
Another factor to take into account is the hardness of the toothbrush, which as a general rule should be medium.
When you visit Oscar Gallo Güemes’ office, be sure to ask about which toothpaste and which type of toothbrush is best suited for your dentin.
For each patient there is an optimal toothbrush and toothpaste.