Definition:

The Mandibular Tendon Reflex is a neurological reflex that involves the contraction of the masseter muscle in response to a tap or strike on the tendon of the masseter muscle.

Key Points:

• Neurological Reflex: A reflex action initiated by the nervous system, without the involvement of conscious thought.
• Masseter Muscle: The masseter muscle is a powerful muscle located in the jaw responsible for closing the jaw and assisting in chewing.
• Contraction: In the context of the Mandibular Tendon Reflex, contraction refers to the shortening and tightening of the muscle fibers in the masseter muscle.
• Tap or Strike: A quick and light physical stimulation applied to the tendon of the masseter muscle, typically using a reflex hammer or finger.
• Response: The response of the Mandibular Tendon Reflex is the involuntary contraction of the masseter muscle, causing jaw closure or clenching.

Explanation:

The Mandibular Tendon Reflex is a monosynaptic reflex that involves the connection between the sensory neuron and the motor neuron in the spinal cord. When the masseter tendon is tapped or struck, the sensory receptors (muscle spindles) in the tendon detect the change in muscle length and transmit the sensory signals to the spinal cord. These sensory signals then directly activate the alpha motor neurons, which in turn, stimulate the masseter muscle to contract. This reflexive contraction helps protect the jaw and teeth from excessive force and is integral in maintaining bite force stability.