Understanding Myofunctional Therapy: Promises, Limitations, and the Evidence Behind It

Understanding Myofunctional Therapy: Promises, Limitations, and the Evidence Behind It

24 June 2024

Myofunctional therapy is a treatment approach that focuses on improving muscle function and oral habits to support better dental and facial development. Much like orthotropics, this therapy aims to modify the functional environment around the teeth and jaws—especially in young patients—through non-surgical techniques such as breathing exercises, tongue posture correction, and swallowing training.

While the concept is appealing, it remains a subject of debate in orthodontics due to a lack of strong scientific evidence. In this post, we’ll explore the similarities between myofunctional therapy and orthotropics, its historical background, and the research limitations surrounding its effectiveness.

What Is Myofunctional Therapy?

Myofunctional therapy addresses habits such as:

• Mouth breathing
• Incorrect tongue posture
• Improper swallowing patterns

The goal is to retrain the muscles in the face and mouth, which some claim can influence jaw development, bite alignment, and even facial structure.

Similarities with Orthotropics

Both myofunctional therapy and orthotropics focus on modifying the environment in which the teeth and jaws develop. They promote the idea that changing oral posture and muscle function—especially during growth—can improve dental and facial outcomes.

Key Similarities:

• Functional Focus: Both treatments aim to guide growth using natural muscle activity rather than surgery.
• Environmental Modification: They emphasize correcting habits such as mouth breathing and improper tongue posture to create a healthier oral environment.
• Early Intervention: Both are primarily recommended for children, when bone growth is most adaptable.

The Evidence: What Does the Research Say?

Despite its growing popularity, myofunctional therapy lacks robust scientific support. Most available studies are retrospective and anecdotal, offering limited insight into cause and effect.

Research Concerns:

• Retrospective Case Studies: These types of studies observe outcomes after treatment and often suffer from selection and reporting biases.
• Lack of Randomized Controlled Trials (RCTs): Without RCTs, it’s difficult to measure how effective the therapy actually is.

There is a clear need for well-designed, long-term clinical studies to validate the claims made by proponents of myofunctional therapy.

Historical Use of Similar Functional Appliances

Many of the principles of myofunctional therapy are not new. Orthodontists have used functional appliances for decades to address similar concerns.

Examples Include:

• Twin-Block
• Andresen Activator
• Bionator Appliance

These devices aim to guide jaw growth by encouraging proper oral function. However, even with their long-term use, high-quality research shows that their effect on increasing jaw size is limited.

Genetics and Jaw Growth: Setting Realistic Expectations

A major claim of myofunctional therapy is its ability to change jaw size. However, the current scientific consensus is clear: jaw size and shape are primarily determined by genetics.

What the Evidence Shows:

• Genetic Factors: These set the blueprint for jaw size and growth potential.
• Minimal Structural Change: While muscle training may improve function and posture, it does not significantly alter the genetic trajectory of jaw development.
• Overstated Claims: There’s no strong evidence that therapy alone can produce dramatic, lasting changes in jaw structure.

Conclusion: An Approach Worth Considering—With Caution

Myofunctional therapy provides a functional, habit-focused approach to orthodontic care. It may be beneficial in improving oral posture and breathing patterns, particularly in children. However, its ability to make significant changes to jaw size or facial development remains unproven.

As with any treatment, it’s important to weigh the available evidence, understand the limitations, and consult with a qualified orthodontist before beginning therapy. While the ideas behind myofunctional therapy are not without merit, the lack of strong scientific validation means it should be approached with a healthy dose of skepticism.