Pica - I guess lots of children with autism do this. We only really have issues with Charlie chewing non-edible items at the moment and at times this has been quite pronounced, particularly when he discovered a liking for carpet underlay and ripped up 3 brand new carpets. We don't have carpets anymore, its obviously very bad for him to chew and eat the underlay and very expensive for us! Anyway, I thought I'd just share a few things we have tried as replacements for the things he chews. Most have had some limited success.
I think he likes the textures in his mouth so I just look out for foods which could give him the same feeling. With the carpet underlay, I started to give him raw mushrooms and crumpets. He now loves crumpets which is great and will play with the mushrooms.
The other main thing that gets chewed is paper. Any paper he may find laying around, annoying but can be kept to a minimum by tidiness (if I had any of that!) but also wallpaper. We are slowly getting rid of most wallpaper in our house and Charlie is helping with the process. Its not so easy to replace, but I came across this sugar/rice paper in Hawkin's Bazaar and I'm trying to remember to offer it to him instead when I see him going after paper.
The other thing is sticks and leaves. Well obviously the leaves can be replaced with edible leaves and believe me, I've tried everything! I've put lettuces in pots in the garden and in the house I've left pots of herbs, cress, living salads etc. But no! He knows they are supposed to be eaten so they get left alone!!
Sand, cotton wool, oats, and dried rice and pulses are all things that would make it into his mouth during play if we didn't intervene. Oh and he will chew fabrics.
We used chewy tubes in the past when James 'nibbled' on stones, something which has thankfully passed. They never really worked for him as it was a different sensation but I did notice Charlie had found one the other day and was using it correctly. I think we heard about those from our lovely Barnardo's Speech and Language Therapist rather than an OT! I know we had to find them ourselves.
The more I think about it, the more I think this is an under-researched and under-treated part of autism. Occupational Therapy is very hit and miss in this area. The boys didn't see one for nearly 2 years after diagnosis and yet their sensory needs are immense.
All comments and suggestions welcome!