consumerbusinessco
- Aug 6, 2021
- 3 min read

Learn How Myofunctional Therapy Can Resolve Lockjaw

Updated: Aug 8, 2021

Myofunctional Therapy can resolve lockjaw in patients who have undergone oral surgery or have Radio Chemotherapy for head and neck cancer. Trismus, also known as lockjaw, is caused by trauma or injury to the chewing muscles. Your chewing muscles serve two functions:

To chew your food
To open your mouth.

Without your chewing muscles, it would be hard to talk, eat, brush your teeth, swallow, and in some cases open your mouth to get your braces measured and installed after jaw surgery.

There are two types of trismus, temporary and permanent. Temporary trismus usually resolves itself in less than two weeks, but it can be very painful in the meantime. Permanent trismus occurs when temporary trismus is untreated.

Trismus can arise for the following reasons:

Extraction of wisdom teeth, especially the lower teeth
Inflammation the surgery creates
Hyperextension of the jaw during surgery
Infiltration of a tumor in masticatory muscles and temporomandibular joint
Involvement of the muscles in the irradiation field or combination of both
Large tumors and high-dose of Radio Chemotherapy

Benefits of a Myofunctional Therapy Program to alleviate Trismus:

Myofunctional Therapy provides a structured treatment program to exercise and ease the pain of the jaw muscles. It provides the following:

Increases the maximum jaw opening of patients
Stop the damaging hyperactivity of masticatory muscles
Restores normal muscle function at rest and for chewing and swallowing.

Increases the maximum jaw opening of patients

Maximal opening of the mouth is described as the greatest distance between the incisal edge of the maxillary central incisor to the incisal edge of the mandibular central incisor. Dental infections, craniofacial malignancies, fractures and myopathies in the head and neck region, and many other reasons may contribute to the cause of reduced mouth opening. Dentists, Orthodontists, and Oral Surgeons face various problems when there is a limited mouth opening. A minimum of 40mm for maximum mouth opening and a minimum of 7mm for other horizontal mandibular movements. Results show an increase in the mean maximal interincisal distance after Myofunctional Therapy/Speech Therapy intervention, reaching a mean value above the threshold considered for trismus.

Stops the damaging of hyperactivity of masticatory muscles

Mastication is a sensory-motor activity aimed at the preparation of food for swallowing. It is a complex process involving activities of the facial, the elevator and suprahyoid muscles, and the tongue. These activities result in patterns of rhythmic mandibular movements, food manipulation, and the crushing of food between the teeth. The movement of the jaw, and the neuromuscular control of chewing, play an important role in chewing, swallowing, and feeding.

Masticatory muscle hyperactivity appears to have an important role in temporomandibular disorders. Temporomandibular disorder is characterized by functional and pathological alterations that affect the temporomandibular joint (TMJ), masticatory muscles, and other parts of the jaw, teeth, and tongue.

Myofunctional Therapy treatment can eliminate or neutralize the hyperactivity of masticatory muscles which improves temporomandibular disorders and mobilization of the joint for maximal jaw opening.

Restores normal muscle function at rest and for chewing and swallowing

At the end of the structured and customized Myofunctional Therapy treatment, smooth movement and adequate range of mandibular opening, a stable terminal point, and normal chewing patterns were achieved. Exercise intervention is important in the long-term treatment of radiation-induced trismus patients who have undergone jaw surgery. This good response to the treatment was enhanced by Myofunctional Therapy.

TASL Speech Therapy Consultants specializes in oral myofunctional disorders, swallowing disorders, and sleep-disordered breathing issues. We diagnose and treat patients with issues of trismus pre/post-surgery and Radio Chemotherapy, temporomandibular disorders, tongue-ties/tongue thrust, sleep-disordered breathing, and disorders that impact chewing, swallowing, and speech function.