Sensitivity to sweet foods is usually caused by decay.
Hot and/or Cold:
Sensitivity to hot and/or cold foods usually indicates:
Worn Teeth (Attrition)
It is not unusual for recent dental restorations to be sensitive to hot, cold, or pressure. This sensitivity should decrease with time. If sensitivity from a recent dental restoration worsens or persists, contact your dentist.
Bleaching can also temporarily cause mild sensitivity during treatment that disappears within a few days.
Sensitivity due to a dental problem will worsen with time and become a toothache. A toothache is not like a headache. It will not just go away, even if the pain temporarily subsides. The problem that is causing the pain will just get worse, as will the pain, and simple treatment may no longer be possible. (See our pages on cavities, root canals, abscesses, and extractions to see how a cavity progresses from a minor to a major problem). At the first sign of a toothache, contact your dentist