DentinDentin Hypersensitivity Hypersensitivity

Zhang QiZhang Qi

Wuhan University School of StomatologyWuhan University School of Stomatology

IntroductionIntroduction

Definition:Definition:

Dentin hypersensitivity is a common condition of transient tooth pain caused by a variety of exogenous stimuli.

CharacteristicCharacteristic

Short , sharp pain.

Most in cervical, then occlusal

StimuliStimuli

The exogenous stimuli include:

Thermal (cold)

Tactile (touch)

Osmotic changes (sweets, drying the surface)

EtiologyEtiology

The primary clinical cause is exposed dentinal tubules.

Two phases of development of Two phases of development of dentin hypersensititydentin hypersensitity

First, dentin has to be exposed.

—lesion localization

The dentinal tubules must be opened

—lesion initiation

The most common clinical cause for exposed dentinal tubules is gingival recession.

Common Reasons for Gingival Recession

1. Inadequate attached gingiva 2. Prominent roots 3. Tooth brush abrasion4. Pocket reduction periodontal surgery5. Oral habits resulting in gingival laceration 6. Excessive tooth cleaning7. Excessive flossing8. others

Reasons for Continued Dentinal Tubular Exposure

1. Poor plaque control, acidic bacterial byproducts2. Excess oral acids, sodas, fruit juice3. Cervical decay4. Toothbrush abrasion5. Tartar control toothpaste

MechanismMechanism

Hydrodynamic theory

—M.Brännström in 1967

The fluids within the tubule are disturbed either by temperature changes or physical osmotic changes.These fluid changes stimulate a baroreceptor which leads to neural discharge (depolarization).

Baroreceptor: a never receptor sensitive to pressure

TreatmentTreatment

A challenge for both the patients and dentists.

It’s difficult measuring/comparing different patient’s pain.

It’s difficult for patients to change the habits.

Treatment StrategiesTreatment Strategies

Plug the dentinal tubules preventing fluid flow.

Desensitize the nerve making it less responsive to stimulation.

Nerve DesensitizationNerve Desensitization

Potassium Nitrate the only one approved by FDA and ADA

KNO3 penetrates through the dentinal tubules to the nerve;K+ may depolarize the nerve and prevent it from repolarizing;Thereby, Preventing it from sending pain signals to the brain.

Covering Dentinal TubulesCovering Dentinal Tubules

Composite or GIC restoration

Crown placement

Periodontal surgery

Occluding Dentinal TubulesOccluding Dentinal Tubules

To plug the inside of the dentinal tubules

Ions or salts: stannous fluoride, sodium fluoride, potassium oxalate, etcPrecipitates: glutaraldehydeResin: dentin sealers

Laser: another choiceLaser: another choice

Treatment StepsTreatment Steps

1. Thorough exam to identify etiology and eliminate tooth fracture and irreversible pulpitis.

2. Potassium nitrate containing product/toothpaste 2×day for at least 2 weeks.

3. Potassium nitrate containing product in a tight fitting dental tray.

4. In-office tubule occluding product.

5. In-office tubule sealer.

6. Dental restoration, or a periodontal surgery, that covers the exposed dentin.

7. Endodontic procedure to remove the pulp.

The patient should be informed of the series of steps that may be necessary to eliminate the problem.