What a dentist checks before replacing an old filling
Before replacing an old filling of any material, a dentist looks for a reason, not a birthday: decay at or under the edges, a fracture of the filling or the tooth, an open or ditched margin that traps plaque, wear that has changed the bite, sensitivity or pain on biting, and, for front teeth, a cosmetic concern you raise. A filling that is intact, sealed and symptom-free is usually monitored, because every replacement removes some healthy tooth and enlarges the restoration.
What changes the answer
The material: amalgam, composite and ceramic behave and fail differently (ADA). The size of the filling and how much tooth remains. X-ray findings on a risk-based schedule (ADA). Your symptoms. Your decay risk and grinding.
The checks
- History: sensitivity, food catching, a changed feel, pain on biting
- Margins with an explorer and floss: catch, gap, ditching, overhang
- Stain versus decay: a dark line is not always decay; softness is the sign
- Fracture of the filling or cracks in the tooth (AAE)
- Wear and bite contacts
- Gum health beside the filling
- X-rays when the findings call for them
Amalgam specifically
The FDA advises that sound amalgam fillings should not be removed solely to replace them, since removal exposes you to more mercury vapor than leaving them in place and removes healthy tooth; it identifies groups who may wish to avoid new amalgam, which is a decision for you and your dentist (FDA).
Watch versus replace
| Finding | Usually |
|---|---|
| Intact, sealed, no symptoms | Watch |
| Stained margin, hard, closed | Watch |
| Soft margin or decay on x-ray | Replace or repair |
| Fracture | Replace or repair |
| Pain on biting | Investigate for a crack |
| Appearance you dislike | Your choice, after discussion |
Questions to ask
What did you find? Is the margin closed? Would a repair do instead of replacement? What would change your mind from watching?
Next step: Request a consultation or call (805) 565-5111. A request is not a confirmed appointment; the office confirms times during its listed hours (Monday to Thursday, 8 am to 5 pm, plus select Fridays).
Old-filling evaluation record
| Check | Finding | Watch / repair / replace |
|---|---|---|
| Symptoms | ||
| Margins | ||
| Stain vs decay | ||
| Fracture or crack | ||
| Wear and bite | ||
| X-ray (if taken) |
Recheck date: ________
Guides are general education; an examination is needed for individual advice.
Sources
- MouthHealthy: Dental Filling Options — American Dental Association
- Oral Health Topics: X-Rays/Radiographs (updated Mar 26, 2026) — American Dental Association
- Six Things You Need to Know About Stress-Related Tooth Injuries Like Cracked Teeth (Aug 2021) — American Association of Endodontists
- Information for Patients About Dental Amalgam Fillings — U.S. Food and Drug Administration
Sources were current when this guide was last updated.
Educational content, not a diagnosis. Please contact the studio to discuss your own situation.