Is carrying the ball with your mouth legal in soccer?

Question

I have an old deflated soccer ball that I play with my dog. Often he will give up on kicking it and pick it up with his mouth. I say this is cheating. He insists it is not.

This got me thinking: If in a regulation game a player managed to somehow grab the ball with his mouth and carry it down the field, would this be against the rules? If so, what would the call be?

Let's assume for the sake of this question that neither the ball nor the player are breaking any rules on their own (e.g. the ball is properly inflated).

Answer 1

There was a similar question about squeezing the ball between two feet and hopping across the field. The answer that @studro gave there applies here as well. The questions though are not duplicates.

An indirect free kick can be awarded to the opposing team because of LOTG 12.2 as already mentioned by @Joe

Playing in a dangerous manner

Playing in a dangerous manner is any action that, while trying to play the ball, threatens injury to someone (including the player themself) and includes preventing a nearby opponent from playing the ball for fear of injury.

or the referee may decide to caution the player for unsporting behaviour. Trying to grab the ball with your mouth/teeth and to game the system can be considered a lack of respect to the game. From LOTG 12.3

Cautions for unsporting behaviour

...

• shows a lack of respect for the game

...

Answer 2

Barring anything better, I would suggest that the following line from the FIFA Laws of the Game (12.2) would apply:

Playing in a dangerous manner

Playing in a dangerous manner is any action that, while trying to play the ball, threatens injury to someone (including the player themself) and includes preventing a nearby opponent from playing the ball for fear of injury.

Holding the ball in your mouth would prevent a nearby opponent from playing the ball for fear of injury (to the player holding the ball), I imagine...