At 7 the 6-yr-old molars would be the very back teeth - they have 2 incisors each side, 1 canine, 1 pre-molar and 1 molar - 20 baby teeth altogether - and then they get the 6-yr-old molars, which are the first permanent teeth. (The pre-molars have 2 little points on top, the molars have 4)
Behind the incisors - baby or adult - he hould now have canine, pre-molar, baby molar, adult molar, in each quarter of his mouth - go andhave a look (never mind if it wakes him up )
If it's not one of the very back teeth it should be OK with no pain relief.