Jill,
Thanks for your question. I had to do some research on this question, so my answer is based only on what I was able to read, not first-hand knowledge.
Non-metallic sternal bands, clips, and glue have all been used with varying success.
Get a copy of your child's records from the surgery, the closure technique will be listed.
Hope that helps.
Clarification~my son did have a full sternotomy. Thank you again, Jill