Galvanic shock, also known as galvanic current or electrogalvanism, is a sudden, sharp, and unpleasant sensation in the mouth caused by an electrochemical reaction between different metallic dental restorations. It often manifests as a "zinging" feeling in filled teeth, particularly when biting down.
This phenomenon occurs when two dissimilar metals, such as an amalgam filling and a gold crown, come into contact in the presence of saliva, which acts as an electrolyte. This creates a miniature battery within the mouth, generating a small electrical current that can stimulate the nerves within the tooth, leading to the characteristic shock-like sensation.
How it Happens
The mouth provides the perfect environment for galvanic shock due to the presence of various metallic materials and an ionic solution (saliva).
- Dissimilar Metals: The primary requirement is the presence of two different metallic restorations. For instance, an older amalgam filling (containing silver, tin, copper, and mercury) coming into contact with a newer gold crown or even a metal utensil.
- Electrolyte: Saliva acts as an electrolyte, allowing ions to flow between the two metals.
- Contact: When these two metals touch, either directly or through a conductive medium, an electrical circuit is completed, leading to the flow of current.
Common Causes and Symptoms
Understanding the triggers and sensations can help identify galvanic shock.
| Aspect | Description |
|---|---|
| Causes | Contact between different metal types of dental fillings or crowns (e.g., amalgam and gold). Contact between a metal restoration and an external metal object (e.g., a fork, spoon, or foil). Differences in electrical potential between existing restorations. |
| Symptoms | Sudden, sharp "zinging" pain: Often described as an electrical jolt or a tingling sensation. Usually localized to one or two teeth. Pain is typically momentary and resolves quickly after the contact is broken. Can sometimes be accompanied by a metallic taste in the mouth. |
Why it Matters
While generally harmless in the long term, galvanic shock can be quite uncomfortable and alarming. It can interfere with comfortable eating and sometimes lead to concerns about the integrity of dental work.
Solutions and Management
If you experience symptoms of galvanic shock, it's advisable to consult a dental professional. A dentist can diagnose the exact cause and recommend appropriate solutions. Common approaches may include:
- Identifying the source: Locating the specific restorations or points of contact causing the reaction.
- Replacement of restorations: In some cases, replacing one of the metallic restorations with a non-metallic material, such as a composite resin or ceramic, can eliminate the issue.
- Adjustments: Minor adjustments to the bite might prevent contact between the dissimilar metals.
For further reading on dental materials and oral health, you can explore resources from reputable organizations like the American Dental Association.
