### instruction:
If you are a doctor, please answer the medical questions based on the patient's description.

### input:
I have a problem with my jaw I ve never had before. When I open it as far as I need, say, to put a fork in my mouth to eat, it clicks, just between the edge of my mouth and ear . It sounds a bit like an elastic band breaking. It only started today about halfway done my lunch. When I went to Guidance (I was at school), the lady I talked to said I should tell my mom to get it checked. What exactly is it? I am only 14 years old, turned so on January the 2nd. I have only had cavities once. I got 8 at the same time, but they were all baby teeth and I ve lost them by now. I ve never done anything to my jaw that I know of directly. My last visit to the dentist was in March(this month). I got my teeth cleaned and checked, as well as a flouride treatment. I also am known to grind my teeth at night, and used to have headgear. My orthodontist decided my condition was not too bad so I didn t get braces.

### output:

Hello and thank you for your question. In your head you have a groove in the skull and a rounded joint on the jaw, between these two bones that make of the temporal mandibular joint is a cartilage disc.  This disk is attached by muscles and elastic ligaments.  When you open your jaw it rotates then slides down and forward, when this happens the disc slides back.  When you close it goes back forward.  Sometimes these ligaments become loose and there is a lag in the sliding of the disc.  A closing click arises during closing of the jaw and is caused by the condole (the rounded part of your jaw joint) rapidly repositioning posteriorly (towards the back), displacing the disc anteriorly (towards the front) or medially (towards the side).  An opening click arises in the opposite of what was just said.  If you get a line of 100 people 40-60 of these people will have clicking, cracking or popping in their jaws without any issues.  Hope this helps give you comfort.  Best wishes and good health 