Does a dental abscess usually hurt?

Somtimes: Dental abscesses are caused by the death of the nerve and living component within the tooth. Some are caused by infections of the gums. The ones that are tooth related often are painful . Gum abscess can sometimes only involve swelling.

Not always: Beleive it or not when you see someone swollen they may not be in any pain at all, that is because all the pressure from the abcess has been released into soft tissue. When there is no swelling the pain is much worse since the pressure is built up and that presses on the nerves in the area and causes pain.

Yes and no: It seems they would cause pain every time. However, that is not the case. The absence of pain does not rule out the possibility of a dental abscess.

Not always: A chronic abscess is a slow developing condition usually related to trauma and may not even be detectable without xrays. The problem is that they can become acute at any time and then the story changes.