Is it bad to chew sugar-free gum? I heard the chemicals in them are bad for you to ingest?

When both of you have braces, and you do happen to get stuck together, is there any way to unhook without help from anyone other than you and him?

1) I'm considering getting my tongue pierced. Is there anything I ought to know before I get it done? What should I look for in a piercing place? Does the piercing ever have negative effects — I don't know, tongue paralysis or something? Thanks!

2) If and when I decide to take my tongue ring out, I worry that there will be scarring tissue or an ugly hole in the middle of my tongue. Is this the case?

1) What is TMJ? What kind of doctor handles this problem?

2) I have a rather odd problem. For the past several years, I have noticed that when I open my mouth wide to yawn or take a bite out of a sandwich, the right condyle of my jawbone slips laterally from the temporomandibular joint, making it difficult, and at times, painful, to close my mouth. I basically have to slip the condyle back into the socket; otherwise, it slips in by itself, which is what causes the pain.

Other than being inconvenient, this has not adversely affected me in any way that I can tell, except that I am now careful not to open my mouth completely when I yawn. I am reluctant to see a doctor about this because I cannot reproduce the situation at will, and don't know if the problem can be diagnosed or detected unless the doctor actually sees the condyle slip out.

Also, any time I have gone to Health Services, it seems that whatever the problem, they just send me home with a jar full of ibuprofen. What do you think is wrong? Is this problem serious? Does it deserve immediate attention? What type of doctor would I need to see and could I get a referral from Health Services?