You may feel minor irritation and notice inflammation in the gums in the region behind the second molars. These teeth development often causes a dull ache close to the back of the jaw that for a number of people can turn into frequent, more evident pain. They usually erupt between the ages 18 to 25, however can take years to completely emerge through the gums. The tooth pain is typically quite intense. It often feels similar to pain in the back of your mouth or else at your jaw. Other people experience aching feelings or pressure in the reverse of their mouths.