How can you tell if I have decay under an old crown?

While sometimes dental radiographs can confirm the presence  of decay and  other times decay can be detected by using a dental explorer to probe the margins of the crown, there are plenty of instances when decay can lurk undetected beneath what otherwise may appear to be a still serviceable crown. Dentists inability to diagnose "hidden" decay can can confound patients, since they may feel that dentistry should have a foolproof way to detect caries in a tooth.

Often our decisions about evaluating old dentistry can be inprecise and dentists can differ on their diagnosis. Clearly old crowns ( more than twenty years old) should be evaluated in a different light than a newly inserted crown. I find that when I do remove an older crown , I often find a partial washout of the permanent cement and or some recurrent decay I was unaware of.

Commonly in my dental practice I find that my older patients can have a "spot" of recurrent decay adjacent to a crown and I have the option of just excavating and "spackling" the area of decay or choosing to remove and replace the entire crown. My decision varies from patient to patient and from crown to crown. I factor in a patient's age, finances, and the apparent fit of a crowns margins.

If I am dealing with an elderly patient with limited finances or compromised health, I tend to be more likely to recommend a discreet repair procedure and not the replacement of their crown. If on the other hand I am dealing with a patient under seventy , who is in apparent good health, I will be more likely to recommend  replacement of their crown.