Author: Boban Fidanoski
Definition of Dentin Hypersensitivity
Dentin Hypersensitivity is short, sharp pain arising from exposed dentin in response to stimuli, typically thermal, evaporative, tactile, osmotic or chemical and which cannot be described to any other dental defect or pathology. It is an exaggerated response of dentin to non-noxious stimuli and satisfies all the criteria to be classified as a true pain syndrome.
Mechanism of Dentin Hypersensitivity
Phases in development of hypersensitivity
Phase One: Dentin is exposed (lesion localization), through either loss of enamel or gingival recession
Phase Two: Dentinal tubules are open to both the oral cavity and the pulp (lesion initiation).
Etiology of Dentin Hypersensitivity
Common causes for most discomfort
Cold (in 35% of the cases), heat, sweet, combination of cold and sweet, acids, touching.
When dealing with hypersensitive teeth, it’s very critical to assess the status of the pulp. What are the steps one should complete during the assessment of the pulp?
By definition, dentin hypersensitivity is a diagnosis of exclusion. Therefore, before proceeding to management and treatment, conditions that present with symptoms mimicking
dentin hypersensitivity must be ruled out. Assessment steps to determine differential diagnosis with pulpal diseases (Pulpopatiae) are:
1. History of pain (chronology, nature, location, radiation, aggravating and alleviating factors)
2. Percussion and palpation tests
3. Inspection of the teeth and surrounding tissue
4. Thermal (heat and cold) and electric pulp tests (EPT)
5. Radiographic examination
Desensitizing agents. Characteristics of an ideal desensitising agent
1. Not irritate the pulp
2. Act rapidly
3. Be effective for long period
Desensitizing chemical agents
1. Potassium Nitrate (blocks neural transmission by pulpal nerves)
2. Fluorides (occludes dentinal tubules)
3. Stroncium Chloride (occludes dentinal tubules, effective on tactile hypersensitivity)
Desensitizing physical agents?
1. Protective Sealants ( Seal and Protect-Dentsply)
2. Lasers (CO2 or Nd:YAG )
3. Glass ionomer cements (hydrophilic, require etching, effective for class V)
Types of self
applied desensitizing agents
1. Potassium Nitrate (KNO3) – 5% in dentifrices
Sodium Fluoride (NaF) –
0.5% in mouthrinse
Stannous Fluoride (SnF2) – 0.4% in gel
Types of professionally
applied desensitizing agents and how to apply them
Duraphat (Colgate Oral)
- 5% Sodium Fluoride Varnish
Gel-Kam Dentin Block
(Colgate Oral Pharmaceuticals)
2. Seat client in upright position (Prevents gagging and accidental ingestion of fluoride gel/foam)
3. Provide client with informations about the procedure and obtain consent
4. Try tray of appropriate size
5. Load fluoride gel/foam into trays: 2ml maximum for children, 2.5ml maximum for adults
6. Isolate teeth with cotton rolls. Dry with air syringe.
7. Insert mandibular tray. (Ensures coverage into interproximal spaces).
8. Press tray against teeth.
9. Air dry maxillary arch and insert maxillary tray.
10. Press tray against teeth and ask client to close mouth and bite gently on trays or cotton rolls
11. Place saliva ejector over mandibular tray. Set timer for 4 minutes. Never leave client unattended. (Maximum fluoride exposure requires 4 minutes)
12. Tilt chin down to remove trays
13. Ask client to expectorate; suction excess fluoride with saliva ejector
14. Instruct client not to eat, drink, or rinse for 30 minutes
15. Record service and type of fluoride used in the client’s chart
Seal and Protect
Nitrate: active ingredient in desensitizing toothpaste
5% Potassium Nitrate (chemical formula: KNO3) is the active ingredient in desensitizing toothpaste. Potassium Nitrate in conjunction with Sodium Fluoride in the toothpaste significantly reduces symptoms within two weeks.
Mechanism of action: Potassium ions penetrate into the dentinal tubules and block repolarization of the sensory receptors of neuron’s dendrites of the pulp those usually carry out the pain impulse to the Central Nervous System.
After initial depolarization and transmittion of the impulse to the brain, a repolarization is expected to occur, where ions of Potassium leave the neuron’s membrane into the surrounding tubular fluid due to a lower concentration gradient. If we apply additional Potassium into the dentinal tubules, concentration gradient of Potassium in the tubules will be higher than the one in the neuron’s membrane and in that way potassium from the membrane won’t be able to exit the membrane and allow repolarization. If repolarization is blocked, nerve can’t conduct another action potential (impulse), and CNS will stop receiving pain impulses. If elevated levels of potassium nitrate are maintained, the depolarized state decreases the perception of pain. It can almost be described as a numbing effect on dentin hypersensitivity.
¨ John O. Grippo at al. Attrition, abrasion, corrosion and abfraction revisited; A new perspective on tooth
surface lesions- JADA, Vol. 135, August 2004
¨ Kielbassa A. Dentine Hypersensitivity: Simple steps foreveryday diagnosis and management. International Dental Journal
¨ Canadian Advisory Board on Dentin Hypersensitivity •Consensus-Based Recommendations for the Diagnosis and Management of Dentin Hypersensitivity
¨ Dentin Hypersensitivity in 21-st Century;Complex causes and successful treatment options – Dani Botbyl, RDH
¨ Eshter M. Wilkins – Clinical Practice of the Dental Hygienist 8-th edition
¨ Darby and Walsh – Dental Hygiene Theory and Practice 2-nd edition
author: Boban Fidanoski
December 20-th, 2006 Copyright - Text, diagrams, figures and photographs