Assessing Tethered Oral Tissues and Understanding Their Role in Orofacial Myofunctional Disorders

by Kari Slade RDH

The world of healthcare is ever evolving, and as science continues to discover the intricate network of systemic health, the focus becomes more holistic or whole body focused. Connective tissues or fascia have been a long-overlooked system of the body that we are just beginning to understand. Dr. Richard Baxter DMD, MS, talks about the role of connective tissue attachments in his book “Tongue Tied: How a Tiny String Under the Tongue Impacts Nursing, Speech, Feeding and More.”1 He has also been a key contributor to current research on tethered oral tissues, as the founder of The Alabama Tongue Tie Center. Dr. Larry Kotlow DDS has also written a book on the implications of breastfeeding and oral development called “SOS 4 TOTS.” Dr. Kotlow has preformed over 10,000 tongue tie releases dating back to 1974.2 As the knowledge of the implications of tethered oral tissues becomes available, recognizing tethered oral tissues, understanding their role in Orofacial Myofunctional Disorders (OMD’s) and referring to the appropriate provider for treatment of the associated symptoms has become an integral component in the comprehensive oral assessment. Treating the symptoms of OMD’s can help improve breathing, airway and quality of sleep for many clients within our practices.

So, what are tethered oral tissues? Tethered oral tissues are the result of a thin string of attachment, called the frenum, being too short, tight, or too thick. Frenums are located on three areas of each arch. The buccal frenums apical to the canines, and the labial frenums at the maxillary and mandibular midline. The sublingual frenum is located on the underside of the tongue. The International Affiliation of Tongue-Tie professionals (IATP) define ankyloglossia (tongue tie) as “An embryological remnant of tissue in the midline between the under surface of the tongue and the floor of the mouth that restricts normal tongue movement.”3 Importance is placed on the limit of function when determining tethered oral tissues, as not all “tissue strings” reduce or impair function. As a result of this, assessment for range of motion and function can be critical when linking tethered oral tissues to symptoms of OMD’s.

Tethered oral tissues are assessed at the buccal, maxillary, mandibular and sublingual frenum attachments. When assessing lip ties, one can gently extend the lip outward to visually assess the tissue attachment. Does the tissue appear thick, thin, stretched? Is there blanching of the tissue?

When assessing the tongue, the shape of the tip (pointed, heart shaped), appearance of the dorsal surface, evaluation of the sublingual frenum, floor of the mouth compensations, and assessment of the total range of motion, all help to gather important data on tethered tissues. Indices such as Total Range of Motion Ratio4 and Kotlow’s Classifications5 provide qualitative data on tethered oral tissues and function.

Tethered oral tissues impact OMD’s by affecting the position of the tongue and lips. When a frenum is restricting motion, mouth breathing, open mouth posture, and low tongue posture may occur. If maxillary attachment is present, the lips may not easily come together at rest. When the tongue is tethered, it may not seal to the palate, potentially resulting in a low tongue posture or tongue that rests on the floor of the mouth. A low tongue posture can also encourage a tongue thrust swallowing pattern. A tongue thrust happens when the tongue is pushing forward into the incisors when swallowing, instead of sealing to the roof of the mouth to aid in pushing the bolus of food towards the oropharynx. Thrusting is one important symptom clinicians should consider when assessing for symptoms of OMD’s.6

When providing a comprehensive oral assessment, a clinical observance or client’s report of some of the following symptoms may warrant investigation for OMD’s. Noting a tongue tie, tongue thrust, mouth breathing, bruxism, reports of snoring, disordered sleep or obstructive sleep apnea can be can indication of untreated OMD’s. Due to the negative connotation of “mouth breathing,” directly asking the client whether they breathe through their mouth will almost always result in a resounding “no.” Using indirect assessment through observing breathing, assessing the client’s ability to tolerate radiographs or ultrasonic water pooling, difficulty with retracting lips, gagging, flared maxillary incisors, coated tongue, vaulted palate and maxillary or mandibular tori are all signs that oral posture may be affected by tethered oral tissues.

Once the symptoms of OMD’s have been assessed, referral to a myofunctional therapist can help the client reach their goals of improving lip and tongue posture, establishing nasal breathing and correcting a dysfunctional swallowing pattern. These goals can be achieved through the implementation of a myofunctional therapy program, which may or may not include referral for frenectomy. Myofunctional therapists can be dentists, registered dental hygienists, or speech language pathologists. A quick Google search or networking with your local dental association may help you to find a local provider. Many OMT programs are also provided virtually, providing clients with the convenience of at-home care. Myofunctional therapists aid clients in improving their oral posture, correcting dysfunctional swallowing and achieving consistent nasal breathing through a series of 12-18 sessions, aimed at training oral muscles and improving the mind-muscle connection with both passive and active exercises, done for two to five minutes, one to two times a day.

As we learn more about the role of connective tissue plays in overall health, one begins to connect the dots between many oral health conditions and reduced airway capacity which can sometimes be a result of an orofacial myofunctional disorder. Understanding and recognizing tethered oral tissues and knowing when to make a referral to a myofunctional therapist can improve oral posture, optimize breathing, improve airway and reduce or eliminate symptoms of OMD’s.


  1. Tongue Tied: How a Tiny String Under the Tongue Impacts Nursing, Speech, Feeding and More. by Richard Baxter DMD, MS. Publish 2018 by Alabama Tongue Tie Center.
  3.  International Affiliation of tongue tie professionals

About the Author

Kari Slade RDH is an Independent Registered Dental Hygienist, who has been passionate about her career since graduating from Aplus Institute of Dental Hygiene in 2007. She is the Director of Kari Panting Slade Dental Hygiene Corporation and owns Something To Smile About. Her clinic provides mobile dental hygiene services and myofunctional therapy in Brantford, Ontario. You can follow her on social media @somethingtosmileaboutrdh or view her website