Does masseter Botox (Chewing Muscle Botox) impair chewing function, and how does it change the facial oval?

Masseter Botox is applied to the masseter muscle, located at the corner of the jaw and the strongest chewing muscle. This procedure relaxes only the hypertrophic (enlarged) portions of the muscle, not the entire muscle. Since the act of chewing is supported not only by the masseter but also by other strong muscles such as the temporal and pterygoid muscles, there is no loss of function when chewing foods of normal firmness (a slight feeling of fatigue with very hard foods is normal in the first week). As the muscle volume decreases, the square appearance at the corners of the jaw softens, and the face tapers downwards, achieving a more aesthetically pleasing V (oval) shape.