How can I encourage chewing?

Some of you may have heard about my bunny that recently has been going through a 6 week treatment for scabies. He's doing really well, all his fur is back to normal and he looks just like the day he arrived in my life

However due to the scabies/mange on his face, eating solid foods and hay caused him unnecessary discomfort, so he never ate it or never chewed during this period. We had noticed on Monday his teeth had become increasingly long in which we immediately went to the vets to have them cut. He has a beautiful smile now, even though one tooth was cut a bit shorter than the rest.

Nevertheless, my bunny has never been a chewer. We've bought him fruit sticks, nibble blocks, mineral blocks, you name it. He licks, everything! He licks carrots, his food, you name it. He's recently put on 200g since his mange treatment and is at a very healthy, somewhat porky 800g (he's a 4 month old hotot dwarf cross with a lionhead).

The problem is he just wont nibble, gnaw or chew anything! Is there anyway I can possibly encourage this behaviour? I've exhausted all my ideas, and I don't want him to have to go to the vets every month to have to experience the awful ordeal or having his teeth cut again. I couldn't bare it.

So he doesn't want to eat hay? Maybe trying a different type of hay like botanical or orchard could get him interested in eating it then you could introduce timothy hay back in slowly.

There are special things about hay that help rabbits grind down their back teeth and keep them in good shape so I think the previous posters advice is good. Fresh Grass also helps grind down the teeth because it also has a very sandpaper like surface so maybe try at least getting him to eat fresh grass. Look for longer more mature grass because it is usually more sandpapery. If you look at the pictures here you will see what I mean..
http://www.therabbithouse.com/blog/2011/10/07/grass-hay-tooth-wear/

Also, Willow is really good to get a rabbit chewing and should also help. If there are parks with lakes or ponds around you there are always some willows- I go to my local park and pick willow all the time- no one even seems to take notice that I'm doing it. My rabbits eat twigs, branches and the leaves and all seem happy and healthy with no ill effects. However there are warnings not to feed too much willow because it has the same ingredient as aspirin- but I have fed quite a bit on occasion with no ill effects in my rabbits. They love it, its their favourite treat.

Thank you for your advice! I will pick up some new hay for him this week, plus we have a bit of a 'wild' patch' in our garden with some tall grass which I'll cut and wash for him. Fingers crossed!