Arab head tossing

Hello,

I was just wondering if anyone has any experience with arabs and this...
https://2img.net/h/i894.photobucket.com/albums/ac150/elmayco/Khalil/7-13.jpg
https://2img.net/h/i894.photobucket.com/albums/ac150/elmayco/Khalil/8-14.jpg

Khalil swings his head right up (as above) then to the side. He is having his teeth checked soon, was meant to be done earlier but our usual dentist let us down and was quite rude. However, lots of people have told me it's just a thing lots of arabs do! There is no particular place or time he does it, he does it in the field, in the stable, in the school whenever he seems to feel like it. It hasn't really caused a problem until i've started riding him, he's nearly had me in the face a few times i've felt his forelock brush my face and it's been a bit close for comfort lol.

He has fallen over in the school twice because of it; once on the lunge he was trotting around then tossed his head and lost his balence, and once when he was loose and cantering around, changed direction sharply and tossed his head at the same time! Cue confused pony on the floor!

I'm at a bit of a loss with this one, i don't want to restrict his head and force it down. I've ordered a fluffy noseband cover as someone suggested it might help. But any ideas of why he does it are welcome.