Special needs son keeps pulling on wires

My 12 year old son has autism and we take him to his orthodontist 2-4 times per week. We cannot keep doing this anymore. He is always touching and pulling wires and at times since brackets break too. Is there anything I can do to stop this? It's becoming a sensory thing for him to do. The only thing I tried is putting that nail polish for nail biting but he continues doing it. He has had braces for just a bit over 3 months