Causes and Treatment Options of Teeth Sensitivity – Sensodyne/Sodium Lauryl Sulfate Free Dentifrice

Teeth sensitivity is one of the common issues to bring patients to dental offices. The symptoms and causes are very variable, which including light sensitivity to hot and cold, moderate sensitivity when eating and drinking sour food or juice, severe tenderness when biting down, or throbbing pain when lying down.

There are many reasons why teeth can be so sensitive. Sensitivity to temperature doesn’t always mean tooth cavity (tooth decay). Sensitivity can occur in other situations such as fractured tooth or old fillings, worn enamel, exposed roots, or gum diseases.

There are preventive care and treatments for sensitive teeth, but treatments are variable on your specific sensitivity. You should go to your dentist to find out what are the causes to induce your teeth sensitivity in order to have the right plan. Fluoride toothpaste or vanishes to strengthen tooth enamel is the initial consideration. Also soft bristled toothbrush or an electric toothbrush are recommended if it appears your enamel is worn from aggressive brushing. Desensitized toothpaste to help block signals to your nerve is also recommended to those patients. Night guard should be indicated to prevent further enamel wear from grinding or clenching habits. If the sensitivity comes from your tooth decay, abfraction, abrasion, or erosion, so crown or filling will be indicated. Patients who have tooth sensitivity becoming severe and persistent, root canal therapy may be recommended. Soft gum tissue graft will be recommended to regain gum recession to cover the root to reduce tooth sensitivity.

Sensodydyne toothpaste with the product name is Sensodyne/Sodium Lauryl Sulfate (SLS) Free Dentifrice is used for anti-hypersensitivity and anti-cavity but has been recommended by many dentists for the reduction of frequency of canker sore or Recurrent Aphthous Ulcers (RAU) because it does not contain SLS which has been identified as a possible cause of RAU.

This product has ADA seal. The manufacturer’s recommendation for adults and children 12 years and over is to apply at least a 1-inch strip of the product onto a soft bristle toothbrush and brush teeth for at least one min, preferably after each meal or at least twice a day (morning and evening) or as recommended by a dentist or physician. Since the connection between SLS and RAU has not been scientifically identified, the SLS-free dentifrice does not carry a claim for the efficacy of reducing the frequency of RAU. Therefore, the patients with RAU will be directed to follow the manufacturer’s recommendation or the dentist’s recommendation.

Sodium lauryl sulfate (SLS) is an anionic detergent that has been used as the major or sole surfactant in most dentifrices for more than 20 years. It emulsifies flavor oils and lipid-soluble antibacterial agents such as triclosan in dentifrices and imparts a foaming sensation with a perception of cleaning.   The concentration of SLS in dentifrices us approximately 0.5% – 2.0% and it is well established that SLS is an irritant to skin at high concentrations.

A study by CM Haaly et al conducted a double-blind crossover clinical trial. The clinical trial was carried out during which 50 subjects used an SLS dentifrice for 8 weeks and an SLS-free dentifrices fir 8 weeks.  Each phase was preceded by a 2-week washout period. None of the parameters measured during this clinical trial was significantly affected by the use of the SLS-free dentifrice as compared with the SLS dentifrices. These results are reinforced by another independent clinical trial led by Fakhry-Smith S et al. the purpose of this study by Fakhry-Smith S et al was to determine the levels of SLS found in the oral cavity following rinsing with an SLS containing mouth rinse and brushing with a SLS containing dentifrice.  The results illustrate that the amount of SLS retained in the oral cavity was minimal (at least 100-fold below that which is needed to cause irritation) and the contact time between SLS and the oral cavity was very short.

However, a single-blind crossover study by Chahine et al shows the opposite results. Twenty-three subjects randomly chose one dentifrice and used for 8 weeks and the other dentifrice for another 8 weeks.  Both dentifrices were not labeled and each phase was preceded by a week washout period.  The results showed that a non-labeled dentifrice significantly reduces the appearances of RAU by almost 80%.  Another two independent studies which were performed in Oslo, Norway confirms the results and the reduction rates were approximately 70% and 60%.

No SLS-free dentifrice carries a claim of the efficacy for reducing the frequency of RAU on the label.  I have visited several retail stores to look for a product that carries the claim and I wasn’t able to find one.  However, I was able to find a Rembrandt product called Rembrandt Classic Extra Gentle online ( which informs the consumers that it is for “people who get them (RAU)”. I was not able to verify the claim on the product label because none of the retail stores I have visited carried the product in the store.

I would recommend this product for patients with RAU due to its safety and possible effectiveness in reducing the frequency of RAU. However, I would certainly inform the patients that not all patients would benefit from it. Based on the research articles mentioned above, the pattern of the efficacy of the SLS-free dentifrice has not been identified, yet the results have been controversial.  Even the clinical trials [4], [5] performed in Oslo, Norway which demonstrated that SLS-free dentifrices significantly reduce the frequency of RAU, showed that certain individuals displayed no differences while using SLS-free dentifrices.  Therefore, I would recommend SLS-free dentifrices to all patients who are willing to invest time and effort because it appears that SLS-free dentifrices can benefit some individuals.


1. Aphthous Ulcer

2. Chahine L, et a1., Chlorhexidine The effect of sodium lauryl sulfate on recurrent aphthous ulcers: a clinical study, Compendium. 1997 Dec;18(12): 1238-40.

3. Emedicine from WebMD

4. Fakhry-Smith S, et al., Clearance of sodium lauryl sulfate from the oral cavity, Journal of Clinical Periodontology. 1997 May;24(5): 313-7.

5. Healy CM, et al., The effects of a sodium lauryl sulfate-free dentifrice on patients with recurrent oral ulceration, Oral Diseases. 1999 Jan;5(1): 39-43.

6. Herlofson BB, et al., The effects of two toothpaste detergents on the frequency of recurrent aphthous ulcers, Acta Odontology Scandinavian. 1996 Jun;54(3): 150-3.

7. Herlofson BB, et al., Sodium lauryl sulfate and recurrent aphthous ulcers. A preliminary study, Acta Odontology Scandinavian. 1994 Oct;52(5): 257-9.