How do dentists evaluate tooth sensitivity with no decay?
A patient says cold water or brushing makes a tooth hurt, yet the chart and the mirror show no cavity. It is tempting to label it "just sensitivity" and move on. Research published in The Journal of the American Dental Association is explicit: dentin hypersensitivity is a diagnosis of exclusion. It is confirmed only after other causes of the pain have been ruled out.
That list of other causes is long. JADA names dental caries, pulpitis, fractured teeth, fractured restorations, postrestorative sensitivity, marginal leakage, chipped teeth, and gingival inflammation as conditions to exclude. Several of them can hide behind a tooth that looks intact. This guide walks through a structured evaluation based on JADA and the Merck Manual Professional Edition.
Step-by-Step Evaluation Guide
1. Ask an Open Screening Question
In the JADA prevalence study, dental teams opened every appointment with the same neutral question: "Have you recently had any pain, sensitivity or discomfort in your teeth or gums?" The question does not mention hypersensitivity, so it does not lead the patient. A positive answer triggered a clinical workup to exclude other causes.
2. Take a Focused Pain History
The Merck Manual recommends that the history identify the location and duration of the pain and whether it is constant or present only after stimulation. Review specific triggers, including brushing, and note any preceding trauma or dental work.
The JADA study also recorded:
- Duration of symptoms
- Frequency and intensity of the pain
- Impact on daily life
- Type and number of teeth affected
- Previous treatments for hypersensitivity
These details matter for diagnosis and for judging whether treatment is working later.
3. Inspect the Teeth and Gums
According to the Merck Manual, teeth should be inspected for shape, alignment, defects, mobility, color, and the presence of plaque and calculus. The oral examination also looks for gum inflammation, caries, and any localized swelling at the base of a tooth that may represent a pointing apical abscess.
Look closely at wear. Merck explains that wear from acid erosion (for example, severe gastroesophageal reflux), from mechanical attrition or abrasion (such as bruxism or a porcelain crown rubbing against opposing enamel), or from aging can make noncarious teeth sensitive once the enamel exposes the underlying dentin. Dentin is sensitive to touch and to temperature changes.
Also check for gum recession. JADA patient guidance lists gums that have pulled away from the tooth roots, from gum disease or vigorous brushing, among the common causes of sensitivity.
4. Percuss the Teeth
If no tooth is clearly involved, Merck advises percussing the teeth in the painful area with a tongue depressor. The findings point in different directions:
- Tenderness to percussion may suggest deep caries with a necrotic pulp and periapical abscess, or severe periodontal disease
- Pain on biting or percussion can also indicate an incomplete (green stick) fracture of a tooth
- Tenderness in several adjacent upper teeth may result from maxillary sinusitis rather than a dental cause
5. Apply a Cold Stimulus to Each Suspect Tooth
Merck describes applying an ice cube or a dental refrigerant-chilled cotton pellet briefly to each tooth and removing it as soon as pain is felt. The key question is whether the pain lingers:
| Finding | Common cause |
|---|---|
| Pain only after stimulation, no lingering pain | Reversible pulpitis (dentinal pain) |
| Pain lingers after stimulation | Irreversible pulpitis |
| No pain with stimulation | Pulp necrosis |
| Continuous pain, worse on chewing or percussion | Apical periodontitis or abscess |
In healthy teeth the pain stops almost immediately. Pain lingering more than a few seconds indicates pulp damage.
6. Use Pulp Vitality Testing When Needed
The Merck Manual's pulpitis chapter notes that diagnosis relies on history and examination with provoking stimuli (heat, cold, and percussion). An electric pulp tester can show whether the pulp is alive, though not whether it is healthy.
7. Take Radiographs Before Calling It Hypersensitivity
"No visible decay" is not the same as no decay. Merck states that radiographs are still the most important tool for detecting caries, determining how deep it goes, and identifying caries under existing restorations. Judicious radiographs also help show whether pulp inflammation has extended beyond the tooth apex and help exclude other conditions.
8. Confirm Dentin Hypersensitivity by Exclusion
Only when caries, pulpitis, cracks, failing restorations, marginal leakage, and gingival inflammation have been excluded does the diagnosis of dentin hypersensitivity hold. JADA adds that diagnosis may also involve a subjective evaluation of how the sensitivity affects the patient's daily life.
Red Flags
- Pain that lingers for more than a few seconds after a cold stimulus, suggesting pulp damage
- Spontaneous pain, or pain that lingers minutes after heat, which Merck associates with irreversible pulpitis
- Pain on biting or percussion, which may point to an incomplete fracture or periapical disease
- A tooth that feels "high" when the patient bites down, which can indicate a periapical abscess
- Localized swelling at the base of a tooth, or induration and tenderness of the floor of the mouth, which may suggest a deep space infection
Common Questions
Why does a tooth with no decay become sensitive?
The Merck Manual explains that wear from acid erosion, attrition, abrasion, or aging can expose the underlying dentin, which is sensitive to touch and temperature. JADA patient guidance adds cracked teeth, worn fillings, tooth grinding or clenching, and gum recession as frequent causes.
Can a patient with irreversible pulpitis point to the right tooth?
Not always. According to Merck, a patient may have difficulty locating the tooth from which the pain originates, even confusing the upper and lower arches, though not the left and right sides of the mouth. That is why testing each suspect tooth individually is important.
What happens if the pulp stops responding to cold?
Merck notes that pain from irreversible pulpitis may cease for several days because of pulpal necrosis. Once necrosis is complete, the pulp no longer responds to hot or cold but often responds to percussion. A tooth that suddenly stops hurting is not necessarily a tooth that has healed.
How is confirmed dentin hypersensitivity managed?
A JADA review recommends delivering desensitizing treatment systematically, beginning with prevention and at-home treatments, with in-office options added when needed. Potassium-containing toothpastes are the most widely used at-home treatments, and most in-office treatments use a barrier such as a topical solution, gel, or adhesive restorative material.
Protocol Summary
- Ask a neutral screening question about pain, sensitivity, or discomfort
- Record location, duration, triggers, frequency, intensity, and recent dental work or trauma
- Inspect teeth for defects, wear, mobility, and color, and gums for inflammation and recession
- Percuss teeth in the painful area and note tenderness or pain on biting
- Apply a brief cold stimulus to each suspect tooth and note whether pain lingers
- Take radiographs to rule out hidden caries and periapical changes
- Diagnose dentin hypersensitivity only after other causes are excluded
How Rovetia Helps
Rovetia keeps a clear clinical history for every dental patient, so pain triggers, cold test results, affected teeth, and radiograph findings are recorded visit after visit. Dictate your exam notes or upload prior records and Rovetia structures them automatically, then ask the AI chat what was found on that tooth at the last appointment before you decide on treatment.
Sources
- The prevalence of dentin hypersensitivity in general dental practices in the northwest United States - The Journal of the American Dental Association
- Toothache and Infection - Dentistry - Merck Manual Professional Edition
- Pulpitis - Dentistry - Merck Manual Professional Edition