There are spaces or sinuses in the bone, above the upper teeth. The roots of some of these teeth are very close to the sinuses.
The nerve supply to the teeth, jaws and to most of the face is provided by branches of the same nerve, the trigeminal nerve.
The sinuses often become infected during a head cold, and this sinusitis can cause the upper teeth to ache and feel “on edge.”
Since the teeth are not the cause of the problem this is also called “a referred pain“.
When the sinusitis clears up, the toothache will go away.