Ankyloglossia (Tongue-Tie)

Etiology

The exact etiology of ankyloglossia remains unknown. An association between X-linked cleft palate syndrome has been reported.[4][5] Ankyloglossia has also been observed in rare syndromes, including Kindler, Opitz, and Van Der Woude.[6] 

Despite this, tongue-tie is mainly seen in patients with no congenital pathologies or diseases.[6] There is evidence that tongue-tie could be transmitted genetically.[6] Furthermore, newborns from mothers who consume cocaine during pregnancy seem more predisposed to ankyloglossia.[7]

Epidemiology

The prevalence of tongue-tie ranges from 0.1% to 10.7%.[6] This is partly because of the lack of a single definition and the differences among investigators.[6] Also, an increase in the incidence of ankyloglossia was noticed in recent years, again mainly because of the several definitions of ankyloglossia being used by clinicians. This has led to overdiagnosing infants and children with tongue-tie and unnecessary surgery.[1][8]

Some less severe forms of tongue-tie may resolve spontaneously with time, explaining why its prevalence is higher in studies evaluating only newborns (1.72% to 10.7%) than in those investigating children, teenagers, and adults (0.1% to 2.08%).[6] Regarding sex, ankyloglossia seems more prevalent in males; no racial preference is observed.[6]

History and Physical

Symptoms of ankyloglossia usually manifest as breastfeeding difficulties and clinical findings in the mother and infant. Breastfeeding complications in the infant may appear as poor latching, constant loss of latch, irritability while breastfeeding, and poor weight gain.[2] The mother usually reports pain while breastfeeding, inadequate milk secretion, or incomplete emptying due to an insufficient infant suck.[2] Examination findings in the mother may include nipple infection, ulceration, or bleeding.[2] This can result in early abandonment of breastfeeding due to frustration, anxiety, and feeling of failure.[2]

The lingual frenulum can be attached to different areas of the tongue and alveolus.[2] A short or thick lingual frenulum may also affect the function of the tongue.[2] The examination must demonstrate tongue mobility restriction; usually, the tongue cannot be protruded beyond the vermillion border.[2] The tongue may also show a heart-shaped deformity and dimpling.[2]

Restricted tongue mobility may affect the pronunciation of consonants and the sounds “s, z, t, d, j, l, ch, zh, th, dg,” and “r.”[9][10][11] Nevertheless, a difference in pronunciation is not necessarily considered a speech disorder.[6] The link between speech disorders and ankyloglossia remains unclear.[12] Ankyloglossia and speech articulation difficulties are common among newborns and children, but an absolute connection between them could not yet be established.[12] There is a need for widely accepted grading systems and better-designed clinical studies.[12]

Mechanical complications have also been reported in adults with ankyloglossia, including difficulties with licking the lips, kissing, eating ice cream, and doing tricks with the tongue.[13] Discomfort under the tongue and tongue cuts from teeth have also been described.[13]

Ankyloglossia is linked to the development of malocclusion, particularly Class III malocclusion. Ankyloglossia's hypothesized association with mandibular prognathism and underdevelopment of the maxilla stems from the notion that the tongue's low position in affected patients exerts forward and downward pressure.[6] However, the evidence that tongue-tie contributes to malocclusion is limited, and this belief may be only based on speculation.[6]

Evaluation

Several factors, including ankyloglossia, can cause breastfeeding problems, but not all infants with tongue-tie necessarily have breastfeeding difficulties.[14] Results from randomized control trials demonstrate that many infants with different severities of ankyloglossia feed well without surgical treatment.[15][16] Since ankyloglossia is easily diagnosed on clinical examination is more commonly believed to be the cause of breastfeeding problems.[1]

Examining an infant with breastfeeding difficulties should not be limited to the lingual frenulum but should be widened to evaluate for other head and neck etiologies.[1] A lactation history from the mother must also be obtained.[1]

The infant must be assessed for an abnormal palate, maxilla, or mandible development; neurologic or cardiovascular disorders; and obstruction in the upper airways that could complicate feeding.[1] It is crucial to gather information regarding various lactation factors, such as the mother's breastfeeding experience, frequency and duration of breastfeeding, and the utilization of formula or pumping devices.[17] In addition to the aforementioned lactation aspects, it is essential to consider maternal factors such as typical discomfort during the initial weeks of breastfeeding, inadequate positioning and support while nursing, nipple anatomy, milk supply, and the possibility of breast infection.[1]

Some healthcare providers, including otolaryngologists and dentists who diagnose ankyloglossia, may occasionally possess limited knowledge about breastfeeding techniques and practices.[1] Inadequate breast positioning is, in most cases, the cause of breastfeeding difficulty; therefore, it is necessary to consult with a lactation expert who will provide lactation advice and support.[1]

Treatment / Management

Even though there is significant evidence that breastfeeding difficulty in infants with ankyloglossia can be improved by frenotomy, some do not benefit from the procedure.[1][15][18][19][20][21][22] Parents must be informed about this possibility before the infant undergoes surgery.[1] Caregivers must also be informed of conservative treatment options, including observation, lactation, and speech pathology consultation.[1](A1)

Frenotomy is usually recommended in infants diagnosed with ankyloglossia experiencing breastfeeding difficulties after other conservative treatments have failed. Early release of the lingual frenulum will decrease the possibility that the mother abandons breastfeeding.[23] Notably, there is limited evidence to support that frenotomy is associated with positive outcomes in other issues besides breastfeeding.[24](A1)

Relative contraindications to frenotomy in infants include neuromuscular disorder, hypotonia, retrognathia, and micrognathia, as a lingual frenotomy may aggravate glossoptosis, obstruct the airways, and complicate swallowing.[1](B3)

It is essential to distinguish between 'frenotomy,' 'frenuloplasty,' and 'frenectomy,' as these terms are sometimes used interchangeably.[1] Frenotomy, also known as frenulotomy, is the incision of the lingual frenulum and is the procedure performed in infants.[1] Frenuloplasty involves cutting the lingual frenulum and repositioning the tissue; frenectomy refers to removing the lingual frenulum.[1](B3)

Frenotomy involves holding the tongue up to tighten the frenulum, then cutting through the fascia-like tissue along a line parallel and close to the tongue. The cut is made in a single motion in less than a second. The infant is restrained by swaddling or in a Papoose board, with an assistant holding the child's head for better support. In a study of 200 infants undergoing frenotomy without analgesia, researchers found that 18% cried during and 60% after the procedure. In a study by Griffiths et al[25], the mean crying time for frenotomy was 15 seconds. Some physicians choose to give sucrose before the procedure to minimize and help with the pain. Placing topical anesthesia is not beneficial, and local anesthesia is contraindicated in infants.[1](B3)

Risks and complications of frenotomy are uncommon but have been described. Rare complications include bleeding, airway obstruction, damage to surrounding structures, scarring, and oral aversion.[1] Bleeding is the most common and is usually resolved with local pressure. A family history of bleeding disorders should be assessed before the procedure, and in older patients, a history of bleeding should be elicited.(B3)

Differential Diagnosis

Breastfeeding difficulties can be caused by many other factors besides ankyloglossia.[1] In neonates experiencing problems with breastfeeding, it is crucial to rule out the following pathologies:

1. Craniofacial pathologies, like retrognathia and cleft palate
2. Nasal obstruction, like in piriform aperture stenosis and choanal atresia
3. Airway obstruction, like bilateral vocal fold paralysis and laryngomalacia
4. Laryngopharyngeal reflux

Patient morbidity and outcomes may worsen if these conditions are not identified and treated before deciding to perform a frenotomy.[1]

Prognosis

The natural history of ankyloglossia remains unknown. For those infants experiencing breastfeeding difficulties, a frenotomy is an acceptable option since it is a low-risk procedure likely to be beneficial for such patients.[2]

Complications

As previously mentioned, infants with ankyloglossia mainly experience breastfeeding difficulties, including poor latching, irritability while breastfeeding, and failure to thrive. Complications for the mother are pain while breastfeeding, deficient milk secretion, nipple ulceration, infection, or bleeding.[2]

Older children and adults with ankyloglossia may undergo mechanical limitations, like difficulty eating ice cream, licking their lips, and doing tongue "tricks."[13] Restricted tongue mobility may complicate the pronunciation of certain letters; however, the link between ankyloglossia and speech disorders remains controversial.[12] Furthermore, the role of tongue-tie in mandibular development, malocclusion, and gingival recession is still unclear.[2]