Sensodyne



Sensodyne is an oral health brand targeted at people with sensitive teeth.[1] Sensodyne products are applied at home by the patient to treat this condition. Sensodyne is owned by GlaxoSmithKline and is marketed under the name Shumitect in Japan.[2]

Contents 1 History 2 Recall 3 Mechanism of action 4 Evidence and efficacy 5 References 6 External links

History
Sensodyne is a brand of toothpaste that was first sold by Block Drug, a Brooklyn, New York-based company established in 1907 by pharmacist Alexander Block.[1] The toothpaste was first marketed in 1961 as a desensitising toothpaste based on a strontium chloride formulation.

In 1980, Sensodyne launched a new toothpaste containing potassium nitrate, a mild local sedative.[3] In 2000 Block Drug was purchased by GlaxoSmithKline.[1] In 2006, Sensodyne Pronamel was released and is marketed as a toothpaste that protects against the effects of dental erosion.

Recall
On July 15, 2015, GlaxoSmithKline Consumer Healthcare announced a recall of certain lots of Sensodyne Repair & Protect toothpaste as well as Sensodyne Complete toothpaste due to the possible presence of wood fragments in the products. The recall also applied to the company's Biotene brand of toothpaste. The recall was a precautionary measure based on a small number of complaints, and no injuries have been reported. The recall applies to products manufactured between 2013 and September 2014, and shipped from June 2013 to April 2015.[4]

Mechanism of action
Sensodyne toothpastes work in one of three ways to relieve the pain of sensitive teeth, depending on the product's active ingredient - potassium nitrate, strontium acetate/chloride, or NovaMin technology.

Potassium nitrate: The potassium ion depolarizes the nerve and stops it from firing. The nerve impulses are thus desensitized and there is no pain.[5]

Strontium acetate and chloride: These compounds share a similar chemical structure to calcium. Strontium based toothpastes (acetate and chloride) are therefore able to replace some of the lost calcium and block the exposed tubules in the dentinal tissue. This helps prevent the movement of the fluid within the tubules in response to a sensitivity stimulus that could otherwise cause tooth pain.[5][6]

Bioactive glass: Newer Sensodyne products [7][8] contain calcium sodium phosphosilicate (brand name NovaMin). NovaMin sticks to an exposed dentin surface and reacts with it to form a mineralized layer. The layer formed bonds with the tooth, and is therefore strong and resistant to acid. The continuous release of calcium over time is suggested to maintain the protective effects on dentin, and provide continual occlusion of the dentin tubules.[9][10]

Evidence and efficacy
A study by the Center for Dental Research did not show any relief of dentin hypersensitivity for a toothpaste containing 8% strontium acetate. In the study the test toothpaste containing 8% strontium acetate and 1040 ppm fluoride as NaF in a silica base, when used for a single topical application and twice-daily brushing for seven days, did not provide statistically significant relief of dentin hypersensitivity compared to a negative control toothpaste containing 1100 ppm fluoride as NaF in a silica base. In contrast, the positive control toothpaste containing 8.0% arginine and 1450 ppm fluoride as MFP in a calcium carbonate base provided significantly reduced dentin hypersensitivity compared to the negative control toothpaste, and was significantly more effective than the test toothpaste containing 8% strontium acetate and 1040 ppm fluoride as NaF in a silica base.[11]