The term mewing only recently entered the popular lexicon, but the concept behind it dates back to the 1970s. The British orthodontist John Mew coined the technique now known as “mewing” through a practice called “orthotropics.” Characterized by strategic tongue positioning, the mewing technique aims to improve facial aesthetics and correct orthodontic concerns.[1]Most facial exercises populating the pages of YouTube, TikTok, and Instagram aim to minimize wrinkles or diminish a double chin. But “mewing,” a viral craze with more than 2.1 billion views on TikTok alone, purports to do much more.What Is Orthotropics?Most experts, including Isaac Chinitz, DDS, a clinical assistant professor of dental medicine at Touro College of Dental Medicine in Hawthorne, New York, say genetics primarily determine jaw size and shape.Mew and his son Michael, a fellow orthodontist, disagree.[1] According to the Mews, the human jaw has become increasingly smaller and more recessed since the 18th century due to radical changes in diet and lifestyle stemming from the Industrial Revolution. As a result of inadequate space, they say, teeth are more frequently crooked and crowded, and faces are less aesthetically appealing. The Mews’ hypothesis is based on that of Melvin Moss, who believed facial bone structure isn’t inherent but develops through functional demands.[1]Enter orthotropics. The Mews’ brand of orthodontics aims to correct structural irregularities and improve facial appearance by correcting “oral posture,” or the alignment of the teeth, lips, tongue, and jaw, Dr. Kahng says.“When the teeth and tongue are correctly aligned, the jaw is in its ideal position. This is known as ‘optimal oral posture,’ and the jaw is able to move freely and easily,” Kahng says. “When the teeth and tongue are misaligned, the jaw can become misaligned as well, leading to jaw pain, headaches, and other issues.”The idea behind orthotropics is that maintaining optimal oral posture and strengthening the jaw will enhance facial muscle tone, force the jaw to expand, and support straight teeth.[1] Many proponents of mewing combine the exercise with other orthotropic-informed concepts, such as chewing gum and eating tougher foods.Orthotropics also uses palate expanders. “Palate expanders are an orthodontic appliance that gradually widens your palate, or upper jaw, over time with control,” explains Jaclyn Tomsic, MD, an oral and maxillofacial surgeon based in Cleveland. “They are medical grade and should only be applied by a licensed dental professional, such as an orthodontist. The application of this appliance by anyone other than a licensed dental professional is not recommended and can cause irreversible damage.”