How can a tooth get a cavity under a filling?+
Plaque can collect along the margin where the filling meets natural tooth. If bacteria reach that seam, the neighbouring tooth structure can be affected, even though the filling itself cannot decay.
Would I feel decay around an old filling?+
Not always. Some people notice sensitivity, while others feel nothing, which is one reason examinations and appropriate images are useful even if the tooth seems fine.
Does the whole filling have to come out?+
Not in every case. When the defect is small and the surrounding material is sound, a localized repair is sometimes possible, while broader decay usually calls for full replacement.
Can the plan change once treatment has started?+
It can, because the full extent of decay is sometimes clearer after old material is removed. Ask your dentist how such a change would be communicated to you.
Will the replacement be another white filling?+
That depends on what remains. Direct composite is common for smaller and moderate repairs, while weakened cusps can point toward an onlay or a crown instead.
Is it worth the trip in from Middlechurch if the tooth does not hurt?+
An assessment can show whether anything needs doing now or can be monitored instead, and pain is not a reliable guide. Call to ask about timing, and how long to allow at the Winnipeg clinic.