Last week we discussed in detail the characteristics of the toothpastes that we sell in our pharmacies. Sensitive teeth, known as “dentin” hypersensitivity occurs when stimulus (hot, cold, chemical or physical) is applied to tooth. Dentin becomes exposed by gingival recession or enamel loss. Enamel is the hardest surface in our body, which consists of 96% hydroxyapatite which is a combination of calcium and phosphate, the bones in our body contain 70% hydroxyapatite and the dentin in our teeth is also 70% hydroxyapatite. Dentin contains tubules which are an open pathway between pulp and the dentinoenamel junction.
Stimulus causes increase in fluid flow through tubule, causing pain at the underlying nerve(pulp) . Dentin hypersensitivity is typically found in patients whose dentin has become exposed due to gingival recession, periodontal therapy and most commonly loss of tooth enamel. As we discussed, tooth abrasion from brushing and toothpaste selection can contribute to the wear and tear on the enamel, which exposes the dentin, and allows pain transmission through the tubules. 55-75% of patients may experience tooth sensitivity during professional whitening treatments.
- The most important step in treating dentin sensitivity is to STOP destructive habits such as aggressive or vigorous cross brushing. Use soft toothbrushes!! 50% of all damage occurs the first 20 seconds of brushing– lots of toothpaste, causes lots of abrasion. Review the “Modified Bass Brushing Technique”- a lot of dental professionals have a saying “It is not the brush, it is the brusher!”
- Consult your dentist, dental hygienist, or pharmacist to recommend a toothpaste with a lower RDA (Relative Dentin Abrasivity).
- Recommend twice-daily use of a desensitizing dentifrice
- Fluoride dental paste: (Prevident-5000 plus®) written as a prescription, works by forming the precipitate calcium fluoride which plugs the tubules. Remind patients to brush on this dentifrice and do not swallow. Patients should not rinse and spit. Fluoride is an effective agent to control dentin hypersensitivity and to prevent root caries particularly when used in higher concentrations. I prefer using fluoride in my practice to desensitize the dentin. I try to stay away from the stannous fluorides because of the metallic taste, compliance usually becomes an issue at some point. Patients just quit using it at some point. Recently I prefer to use products such as MI paste(GC America) and 3M’s Clinpro 5000. Both these products possess regenerative capability. They taste good so compliance is improved.
- Potassium nitrate (5%) and strontium chloride 10% alter membrane potential along the dental nerves, after passing through dentinal tubules. If no relief after twice daily brushing for 2 or 3 weeks, recommend a visit to dentist. 10% strontium chloride hexahydrate is an effective means for reducing the discomfort and pain engendered by thermal and tactile stimuli in patients with dentinal hypersensitivity.
- 5% potassium nitrate (KNO3) lower nerve sensitivity. The potassium ions are thought to block the synapse between nerve cells, reducing nerve
excitation and the associated pain. The effects of strontium are based on the exchange of calcium for strontium in biological processes. Strontium impairs nerve stimulation by changing stimulus transmission
- All these treatments are designed to reduce flow into the dentin tubules by occluding or sclerosing the tubules.(5) Active ingredients include stannous fluoride, strontium chloride hexahydrate, and aluminum, potassium or ferric oxalates and fluorides.
- 5% KNO3 can also occlude the dentinal tubules and reduce fluid flow within the tubules.
- Strontium chloride and strontium acetate have been incorporated in toothpastes for many years and are well documented. While studies show improvement in patients’ perception of pain, the effectiveness of the product at reducing symptoms appears to increase with increased usage.
- Prevident® 5000 Sensitive teeth contains 5% potassium nitrate along with the Sodium Fluoride 1.1% (which is 4 times stronger than OTC toothpaste).
Have a great day on the bench!
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1. Potassium nitrate, sodium fluoride, strontium chloride, and NovaMin technologies for dentin hypersensitivity
By Maria Perno Goldie, RDH, MS