Untangling the tongue-tie epidemic

How has the trend of painful and often unnecessary frenotomy for breastfeeding babies come about?

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“Curiouser and curiouser!” cried Alice

Our breastfeeding babies appear to be in the grip of a tongue-tie epidemic. Or more accurately, in the grip of a tongue- and upper lip-tie epidemic.

These days, when parents look at certain providers’ websites and social media, they might form the impression that a rampant overgrowth of oral connective tissue is taking over our babies’ mouths, tethering down those little tongues and lips. They might form the impression that trimming back this excess tissue early on is a necessary hygiene measure, which protects breastfeeding, speech, orthodontic development, and healthy sleep. They see long lists of references put up as proof.

Frenotomy often occurs without the knowledge of the family’s GP, because the lactation consultant, child-health nurse, midwife, or chiropractor refer directly to the dentist. There are a number of busy dental clinics dedicated to tongue-tie treatment here in Brisbane. Parents spend up to $1000 on laser or scissors frenotomies, stretching the wounds three to six times a day for two or three weeks afterwards, and bring the baby to weekly craniosacral or oral myofunctional therapy, as advised.

The therapists teach parents to stretch and massage their child’s oral frenula, cheek, and tongue multiple times a day. Parents are warned it may take six to eight weeks to see the full benefits of these treatments, which are promoted as multi-disciplinary and holistic.

In my opinion, oral laser surgery hurts babies, as does wound stretching. Laser burns the connective tissue down to the muscle under the tongue, or to the upper gum, minimising bleeding. I regularly see babies after laser surgery with oral aversion and worsened breastfeeding problems.¹ Sometimes the sites become infected.² I once saw the underbelly of a tongue somewhat separated by a frenotomy that went too deep. I often see pale tight cords of scar tissue under the tongue.

During the 2016 Possums Education national tour, concerned health professionals told of a baby admitted to hospital for transfusion after bleeding from a scissors frenotomy for “upper lip tie”. Anecdotally, Emergency Department presentations post-frenotomy are increasing.

How has this trend of painful and unnecessary surgery in our babies’ sensitive little mouths come about?

Prevalence

Alice was more and more puzzled 

From the 1950s, classic or “anterior” tongue-tie was typically overlooked as a cause of breastfeeding difficulty. The structure and function of the infant’s oral cavity, other than in the case of gross anomaly, was rarely assessed. In a literature review in 2005, authors Hall and Renfrew acknowledged that the true prevalence of ankyloglossia remained unknown, although they estimated 3% to 4% of newborns were affected.³

In 2004, the diagnosis of “posterior” tongue-tie was introduced in an American Academy of Pediatrics newsletter, at a time when the baby’s wrists and forearms were deliberately crossed over his or her chest during breastfeeding – a technique now acknowledged to result in positional instability and breastfeeding difficulty.⁴  Subsequent attempts to quantify prevalence of tongue-tie rest at between 4% to 10%, but remain of poor quality. This is because all research into tongue-tie since 2005 is compromised due to a lack of definitional clarity concerning the diagnosis.

Now, classic tongue-tie is conflated with “posterior” tongue-tie, because providers claim that “behind every anterior tongue-tie there lies a posterior tongue-tie”.

Between 2004 and 2013, the rate of frenotomy increased by 90% in Canada.⁵  In the United States, an 870% increase in frenotomy rates is documented between 1997-2012.⁶

Similarly, in Australia, new epidemiological data shows a similar increase in the rate of Medicare-funded frenotomies since 2006, and these data do not consider laser surgery or scissors frenotomy by dentists, who are most likely performing the majority of frenotomies.⁶ You don’t need to be an epidemiologist to conclude that these patterns are typical of over-treatment. The gloriously wide range of normal variations of the frenulum under the tongue and upper lip are labelled abnormal these days, and blamed for breastfeeding and unsettled behaviour problems.^{7, 8}

Evidence

“Give your evidence,” said the King. “Shan’t,” said the cook.

Three systematic reviews show only weak evidence that frenotomies benefit breastfeeding babies.^9-11 In my view, these are likely to underestimate the benefits of frenotomy for classic tongue-tie, and overestimate any benefits from frenotomy for posterior tongue-tie, because of definitional confusion.

Research put forward to support the benefits of oral surgery is severely methodologically flawed. The results of pre-and post-frenotomy questionnaires and chart reviews, are often  provided by high profile American providers of laser surgery who promote the concepts of “posterior” tongue-tie, “upper-lip” tie and “aerophagia induced reflux” internationally^12-17 even though these methodologies are notoriously prone to interpreter bias.¹⁸ The flourishing industry of frenotomy for “oral ties” is championed by the Australasian Society for Tongue and Lip Ties, which loudly promotes itself as evidence-based, and is subsidised by both Medicare and private health insurers.

Concerningly, prominent providers even assert that it would be unethical to conduct a randomised controlled trial evaluating laser surgery, claiming the risk of harm to babies by not proceeding with laser frenotomy is
too great!^{19, 20}

Not breastfeeding impacts on orthodontic development.²¹ However, to believe that therefore oral connective tissue surgery improves orthodontic development is to confuse association with causation, since there is no evidence-based biomechanical rationale for why surgical intervention (other than for classic tongue-tie) might improve breastfeeding outcomes.

It seems sensible to think that a classic tongue-tie could interfere with articulation and dental hygiene for some, although the research definitions have been so confused by the introduction of the term posterior tongue-tie that this cannot be demonstrated at this time.

Families are warned about various developmental risks of not proceeding with laser surgery, which frightens them into compliance, though there is no evidence to support these claims. However, threatening developmental risk will increase the chances of reported positive outcomes post-laser surgery, because of the powerful neurobiological impact of expectation.²²

The absence of baseline data elucidating the normal spectrum of newborn oral connective tissue diversity underscores how matters related to clinical breastfeeding support are still not a health system or research priority. In fact, I’d argue that this lack of investment in clinical breastfeeding research is the important story underlying the oral-ties controversy. This epidemic is, to my mind, a painful sign that clinical breastfeeding support is in crisis.

In that sense, the tongue- and lip-tie epidemic (not to mention the buccal tie epidemic) is also
an opportunity.

Identification and classification

“There’s more evidence to come yet, please your Majesty,” said the White Rabbit.

Since existing evidence is methodologically poor, all current guidelines concerning management of ankyloglossia remain of limited use. Contemporary definitions of tongue-tie confuse function with structure. Oromotor and tongue function are affected by multiple variables including fit and hold (“latch and positioning”). Structure is anatomically variable, for both the tongue length and appearance, and the lingual and maxillary frenula.

In clinical practice I find it useful to rate the anterior membrane by the percentage of the under-surface of the tongue into which the membrane connects, applying the first two categories of  the Griffiths Classification System.²³

Since there is a wide spectrum of lingual frenula morphologies and elasticities, deciding where to draw a line between normal variant and classic tongue-tie will depend on clinical judgment concerning the infant’s capacity for pain-free efficient milk transfer. If the mother-baby pair are able to breastfeed comfortably with a visible anterior membrane (and many do) then this is not actually a “tie” of the tongue, but merely a visible anterior membrane, requiring no further intervention.

In my view, a classic tongue-tie in a newborn should receive a simple scissors frenotomy as soon as possible, in order to protect the woman from potential nipple damage. Since a scissors frenotomy for a prominent anterior membrane is pain-free and of minimal risk, I may, with parental consent, err on the side of performing this even if I’m uncertain about its necessity.

In our specialised work with breastfeeding mothers and babies at the Possums Clinic, we find no use for the diagnoses of posterior tongue-tie and upper lip-tie, not to mention buccal ties, and argue that these are misconceptions. Labial frenula have been classified type I-IV,²⁴  but should not be pathologised as “ties”, let alone surgically ablated. This grading of the labial frenulum is clinically irrelevant. Ablation of the labial frenulum in infancy may risk a worsened gap between the front teeth later in childhood, due to scarring.

The use of diagnoses increases parental pressure for intervention, even if parents are advised that the diagnosed condition is harmless.²⁵ New diagnoses should only be introduced with great caution, because they are known to risk a cascade of overtreatment.^{26, 27}

Treatment

Alice was a good deal worse off than before. 

A severe classic tongue-tie that appears at risk of haemorrhage due to thickened and vascularised tissues may benefit from laser surgery, which will control the bleeding, but most of us won’t encounter these in our life-times, since they are very rare. I would refer to an ENT surgeon for this, who may use laser.

I would advise avoiding paediatric dentists who use scissors for deep frenotomies, due to the risk of haemorrhage – I have observed babies subjected to painful sutures under the tongue or in the upper gum to control bleeding.

I propose that a simple scissors frenotomy is generally all that is required for a classic tongue-tie. Wound stretching places babies at risk of oral aversion, due to repeated uncomfortable or painful digital intrusion. There is no scientific reason to believe that wound stretching post-laser frenotomy alters the inevitable closing of a wound or the contraction of scar tissue over time.

Biomechanical model of infant suck

So she went back to the table, half hoping she might  find … a book of rules.

In my collaboration with the Human Lactation Research Group at the University of Western Australia, who use ultrasound to elucidate the biomechanics of infant suck during breastfeeding, we have shown that the model of infant sucking, upon which laser surgery for posterior tongue-tie and upper lip-tie is based, is inaccurate.^{28, 29} The upper lip is not involved in breastfeeding or milk transfer, other than to rest neutrally against the breast and contribute (with multiple other contact sites during the symmetric face-breast bury) towards the seal. It certainly does not need to flange for pain-free milk transfer.

Actually, if we can see the upper lip we are inviting inefficient milk transfer, fussiness at the breast, and nipple pain for many breastfeeding pairs.

The tongue does not take an active lead in infant sucking, but responds dynamically to intra-oral breast tissue volume: that is, the tongue’s shape, elevation and spread conform to the amount of breast tissue in the mouth.^{28, 29} 

We have called this new understanding of the biomechanics of infant suck in breastfeeding the Gestalt model. The critical driver is a reflex depression of the jaw, which generates intra-oral vacuum. If the baby is fitted well into the woman’s body, this repeated reflex action incrementally draws more and more breast tissue into the mouth until the jaw is held wide open, the nipple tip is protected near the junction of the hard and soft palate, and optimal milk transfer can occur.

The tongue does not need to actively lift midway to the palate, to lateralise, or to extend beyond the lower gum/inner edge of lower lip. It does not strip the breast or have peristaltic movements.^{28, 29}

Since the tongue does not need to actively grip or strip the breast, or compress the breast for milk transfer, but simply follow the jaw depression and mould around the available intra-oral breast tissue volume, we do not need to rely on unproven methods such as laser surgery to try to establish increased tongue mobility: a simple scissors frenotomy for a classic tongue-tie allows the tongue to safely perform it’s moulding, cushioning role.

Parents are told that the digital intra-oral manoeuvres and massage interventions of craniosacral therapy or oral myofunctional therapy stretch or relax muscles and connective tissue, and teaches the tongue new movements, but this misconception is also based on the same out-dated understanding of the biomechanics of infant suck.

Anything that directs parental financial resource and time investment away from the practice of optimal fit and hold delays the critical repair of the disrupted breastfeeding relationship, and is disempowering for women. Craniosacral therapy and related techniques simply cannot compare with healthy effects on postural alignment and functional musculoskeletal health achieved by optimal positional stability and fit and hold, repeated over and over for many hours each day.

Innovative support for breastfeeding

This was such a new idea to Alice, that she was quite silent for a minute or two.

The promotion of surgical release of posterior tongue-tie, upper lip-tie and buccal tie is the latest in a series of inappropriately medicalised interventions for breastfeeding problems.^30-33 We inhabit complex biophysical and sociocultural contexts, where “trusting instinct” is definitely not enough for most of us at the beginning of our breastfeeding journey. Yet the painstaking art and science of supporting a woman and her baby’s competence is easily sacrificed to the seduction of the medicalised silver bullet.

Fussing at the breast, difficulty latching, pulling or slipping off, back-arching (signs of positional instability and poor fit and hold) and/or excessive flatus, explosive frothy stools (signs of functional lactose overload) have been mistakenly diagnosed as signs of gastro-oesophageal reflux disease, allergy, or lactose intolerance since the early 1990s, and are now often attributed to oral ties.

Similarly, frequent feeding, broken sleep, and marathon feeding are signs of poor milk transfer, often associated with crying due to poor satiety, but are also still commonly misdiagnosed as signs of GORD, allergy, lactose intolerance, and, most recently, oral ties.

There are three very common breastfeeding problems underlying these behavioural signs, which are then so often inappropriately medicalised: suboptimal fit and hold, conditioned hyperarousal of the sympathetic nervous system, and functional lactose overload.

Suboptimal fit and hold leads to suboptimal positional stability, which may result in nipple pain and damage, poor milk transfer, and fussing at the breast. The neurobiological model of infant crying describes the conditioned sympathetic nervous system hyperarousal that occurs if an infant is repeatedly frustrated during breastfeeds by positional instability and poor fit and hold.³¹ Nipple pain is also commonly inappropriately medicalised as due to thrush, but often(as long as we have excluded unusual medical conditions) results from poor fit and hold.³⁴ A generous supply or poor breast drainage over time may result in a functional lactose overload, with a bloated gassy abdomen, frequent feeds, high weight gain, and crying, and simply requires appropriate management.^{30, 35, 36}

To illustrate the scale of the blindspot that we have in our health system concerning clinical breastfeeding support, mothers are still widely taught the strategy of shaping or squeezing the breast with the ipsilateral hand, supporting the infant on the back of the neck with the other, and stimulating a wide gape before pushing the baby on. Yet this approach has been demonstrated in Robyn Thompson and her team’s recent large and well-conducted Australian study to increase the risk of nipple pain fourfold.³⁷

The “physiological” (or mammalian or baby-led) approaches to breastfeeding have been a major advance by our clinical breastfeeding support pioneers over the past decade, and are foundational.^38-40

However, baby-led breastfeeding is simply not enough for many of our women, who still develop nipple pain and other problems.

Multiple well-conducted studies show that popular fit and hold strategies, including mammalian methods, do not improve breastfeeding outcomes.^{38, 41-47}

We have not yet paid enough attention to the complexities of empowering women to fit together with their baby across our gloriously diverse anatomies for pain-free efficient milk transfer. This needs to occur across great diversities of breast shape, breast tissue elasticity, nipple shape and length and elasticity, breast-abdominal interface, and infant chin, palate, tongue, lips and oral connective tissue.

In order to further research in this field, women need a teachable, reproducible and empowering approach to fit and hold in breastfeeding. In the hope that it might be helpful for others, we have taken steps at our clinic to make the gestalt breastfeeding approach, which we find so effective in our work, widely available online for both parent self-help, and for health professionals.⁴⁸ Gestalt breastfeeding builds on the work of many clinical pioneers, and integrates our own clinical experience with the new understandings from ultrasound imaging, so that women are empowered as they activate their baby’s breastfeeding reflexes and experiment with positional stability and intra-oral breast tissue volume across diverse anatomies.

Gestalt breastfeeding also integrates psychological strategies for managing the difficult thoughts and feelings that arise when there are breastfeeding difficulties.

More broadly, gestalt breastfeeding is one of a number of programs that comprise Neuroprotective Developmental Care in the Community.

Certification workshops are available online at :www.education.possumsonline.com.

When our generalist’s mind, with its proclivity for integration across disciplines, is applied to the research literature it becomes apparent that problems of breastfeeding often can’t be considered separately from problems of maternal mood, sleep and crying in early life. In the meantime, a quick chat with the women that you see during pregnancy about the current risk of overdiagnosis and overtreatment of other “oral ties” may be of value.

Dr Pamela Douglas is Medical Director, The Possums Clinic, Highgate Hill, Brisbane; Adjunct Associate Professor, Maternity Newborn and Families Research, Collaborative MHIQ, Griffith University; and Senior Lecturer, Discipline of General Practice, The University of Queensland

Acknowledgement: Some parts of this essay have been adapted with permission from another article by the author, contributed to the ‘Tongue-tie Roundtable’ in Clinical Lactation, the journal of the United States Lactation Consultants Association, and which is in press.

The italicised quotes are from Lewis Carroll’s Alice’s Adventures in Wonderland, first published in 1866 by Macmillan and Co of London; Books of Wonder, Morrow & Co, New York 1992.

Conflict of interest: Dr Pamela Douglas is Medical Director of the Possums Clinic, a registered charity which sells the Gestalt Breastfeeding Online Program and The Possums Sleep Film. All revenue goes towards the further development of education and research.  

References: 

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7. Douglas PS. Deep cuts under babies’ tongues are unlikely to solve breastfeeding problems 2016. Available from: https://theconversation.com/deep-cuts-under-babies-tongues-are-unlikely-to-solve-breastfeeding-problems-54040.

8. Douglas PS. Tongues tied about tongue-tie. Griffith Review Online. 2016.

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