Which of the following behaviors is not typically associated with abnormal TMJ function?

Healthy chewing is indeed the correct choice because it represents a normal and functional use of the temporomandibular joint (TMJ). In a healthy situation, chewing is a necessary and natural activity that does not typically contribute to TMJ disorders or abnormal function. Proper chewing requires coordination of the jaw muscles and the TMJ without causing stress or injury to the structures involved.

In contrast, thumb sucking, nail biting, and tongue protruding on teeth are behaviors that can lead to or exacerbate abnormal TMJ function. These actions may create unnatural forces on the jaw or encourage misalignment of the bite, which can result in discomfort, pain, or dysfunction of the TMJ over time. Understanding these unhealthy behaviors is crucial for identifying risk factors associated with TMJ disorders.