If you’ve been using a regular toothpaste all your life, it can feel pretty strange to use something like the tooth powder we told you about  last month or a product like “Toothy Tabs.”  They just don’t foam.
Just as a minty flavor has come to be associated with freshness, so foam has come to deliver a signal that the mouth is getting clean. To many, when it’s missing, something just seems wrong .
In 1972 Colgate Palmolive (CP) launched the world first non foaming toothpaste but it was a sales nightmare. From 1972 to 1974 CP was able to sale on 1000 packets in US. CP went back to its customers to ask for their preference and most preferred foaming toothpaste. The reason behind was psychological, most people who used non foaming toothpaste felt that their teeth were not enough clean, while some felt the brushing was incomplete and hence reversed to foaming toothpaste.
But is there any reason why a toothpaste should foam? Some folks argue as much , calling it “an important aspect of toothpaste.”
Foam helps distribute the cleansing ingredients throughout your mouth, including between teeth, and helps remove plaque and other debris from the mouth.
Evidence doesn’t really seem to support its importance, though.
For instance, a 2016 study in Clinical Oral Investigations  found no difference between foaming and non-foaming toothpaste with respect to plaque (biofilm) removal and the health of the gums. Both were effective.
A similar study  the following year in the International Journal of Dental Hygiene reached a similar conclusion, comparing pastes with sodium lauryl sulfate (SLS) , the most common foaming agent, to those without.
No significant differences could be observed with respect to the effect on plaque and gingivitis between SLS-containing and SLS-free dentifrice containing enzymes, colostrum and low concentration zinc.
Yet both also found that participants preferred the SLS pastes for their flavor, “freshness,” and, yes, the foaming effect.
Now, in so far as those things help encourage a person to brush the full two minutes twice daily that dentists recommend, they’re great. On the downside, SLS appears to be not so great for the rest of your mouth.
The main reason SLS is put into toothpaste is for the foam it creates. It doesn’t do anything else – well, except make orange juice taste terrible  right after you’ve brushed. And damage the soft tissues of the mouth. As one dentist recently reported in a letter to the BDJ ,
Recently, a systematic review reported on SLS based dentifrices and their influence on recurrent aphthous stomatitis. The results also mentioned that SLS-free dentifrices showed significant reduction on number, duration, episodes and pain among recurrent aphthous ulceration (Sutton’s disease) patients. In addition, SLS has been linked with other adverse effects likely to compromise oral health such as local irritation of mucosa leading to desquamation. Due to desquamation the integrity of the oral mucosa is compromised, thus initiating aphthous stomatitis. Globally, aphthous stomatitis is reported as being among the most common oral mucosal pathologies.
To put it in plain English, evidence suggests that SLS may damage cells, leading to recurring canker sores – and that patients with mouth ulcers improved after switching to an SLS-free toothpaste.
It can also increase mouth dryness and make the oral environment more acidic.
We recommend that you opt for SLS-free, as well as fluoride-free, products for cleaning your teeth – if you choose to use a product at all. For research also has shown that toothpaste actually makes little difference  on plaque (biofilm) removal. Brush with the proper technique , and you’ll be doing a good job either way.