The concept of mewing has gained significant attention as a non-surgical method for reshaping the face, with claims that proper tongue posture can lead to a more defined jawline and the expansion of the palate. Mewing is a philosophy that centers on maintaining the correct resting position of the tongue against the roof of the mouth, or the palate. The central question is whether this sustained posture can truly generate the force necessary to achieve skeletal expansion of the upper jaw. Investigating the science behind facial bone structure can determine the validity of this popular internet phenomenon.
Understanding the Mewing Technique
Mewing is a technique rooted in the principles of orthotropics, a practice focused on guiding facial growth through proper oral posture. The core instruction is to ensure the entire tongue is pressed flat against the palate, not just the tip. This posture requires the back third of the tongue to make contact with the soft palate, engaging the muscles in the throat and under the jaw. Practitioners are instructed to maintain this position consistently, even during swallowing. The correct posture also involves keeping the lips sealed and teeth gently touching or slightly apart, promoting nasal breathing. The underlying theory is that this gentle pressure encourages the forward and outward growth of the maxilla, which would theoretically widen the palate over time.
The Biomechanics of Palate Expansion
The palate is formed by the maxilla bones, which are joined together at the midline by the midpalatal suture. True skeletal palate expansion involves applying force to separate these two bones along this suture. The structure of the midpalatal suture is the primary factor determining the feasibility of expansion. In children and adolescents, this suture is composed of flexible connective tissue and has not fully fused, allowing an external orthodontic appliance to successfully widen the maxilla.
As a person ages, the midpalatal suture undergoes maturation and fusion, becoming rigid and heavily interdigitated. In adults, this fusion significantly increases the resistance to separation, meaning non-surgical forces are unlikely to cause a true skeletal change. The mechanical force required to overcome this rigid structure is substantial. Applying insufficient force often results in dental tipping, where the teeth move within the bone, rather than the desired skeletal expansion.
Scientific Evidence and Professional Consensus
The professional consensus among orthodontists and craniofacial specialists is that mewing, performed solely with the tongue, lacks high-quality scientific evidence to support claims of skeletal palate expansion. No randomized controlled trials have confirmed that the gentle, sustained pressure from the tongue alone can separate the fused midpalatal suture in adults. The forces generated by the tongue are measured in grams, which is insufficient to cause structural separation in a mature jaw.
Any perceived changes from mewing are often attributed to improved muscle tone and soft tissue alterations, such as a temporary reduction in a double chin, which can enhance the appearance of the jawline without skeletal modification. Attempting to force the jaw or tongue into an incorrect position can lead to unintended complications. These potential negative outcomes include the tipping or shifting of teeth, the development of an open bite, or temporomandibular joint (TMJ) stress. Major professional bodies have issued warnings against unsupervised attempts to alter facial structure with non-clinical interventions.
Safe and Effective Palate Expansion Methods
For individuals who require true skeletal palate expansion, orthodontic and surgical methods are the established standard of care.
Expansion for Growing Patients
In growing patients, a Rapid Palatal Expander (RPE) is commonly used. This fixed appliance applies continuous, controlled force to separate the maxilla at the midpalatal suture. This device is adjusted periodically by the patient or parent and is effective because the suture is still flexible.
Expansion for Adults
For post-pubertal adolescents and adults, where the midpalatal suture has fused, effective expansion requires more advanced techniques. One option is a Mini-screw Assisted Rapid Palatal Expander (MARPE), which uses small bone screws anchored directly into the palate to apply force, minimizing unwanted movement of the teeth. For cases requiring significant expansion, Surgically Assisted Rapid Palatal Expansion (SARPE) is performed, where an oral surgeon strategically loosens the fused jaw bones before an expansion device is activated. These interventions generate the precise, high-magnitude force needed to achieve skeletal separation that non-device tongue posture cannot provide.