S.E.
Did you try freezing his teething ring or if he uses a pacifier freeze that? Or you can put and ice cube in a wash rag and place it on the the tooth. It pops work nice too. try freezing a mini bagel and have him chew on that. I know this sounds strange but try rubbing a little vanilla extract on the area where the tooth is coming in. It gives a warm and numbing feeling. You can also try clove oil for the same effect. When giving Tylenol rub the liquid directly on the sore area.
Good Luck
S.