Giving up the paci and teething

Li
My son is 15 months. When he was 10 months I started only letting him have his paci at nap amd bedtime. This was a very smooth transition and he didn't seem too bothered by it. Now that he is getting his molars in he has the urge to suck or chew constantly. During the day he chews on his fingers and toys. This is a problem because 1) he is with other children all day and is flu season and 2) I do not want him to develop a habit of chewing/sucking on his hands. I know older children that still do this to self soothe. He has been going to his crib lately trying to get it out. Today I gave it to him and he has not put one toy or finger in his mouth.
My question is- I don't want to take a step back with giving up the paci because he has done so well only using it at nap and bedtime the lastfive months. but I also don't want him to start a habit of putting toys and hands in his mouth. Are there any oral stimulating activities you can think of beside food and drink? I have tried giving him teethers but he trades it out fir another toy or his hand in no time