Abstract
OBJECTIVE To review the diagnostic criteria for, the prevalence of, and the effectiveness of frenotomy for treatment of ankyloglossia.
DATA SOURCES MEDLINE and CINAHL databases were searched for articles suitable for a methodologic review of studies on various aspects of ankyloglossia.
STUDY SELECTION Studies that presented data on patients and addressed ankyloglossia in relation to breastfeeding were selected. Case reports, case series, retrospective studies, prospective controlled studies, and randomized controlled trials were included in the analysis. Opinion pieces, literature reviews, studies without data on patients, studies that did not focus on breastfeeding, position statements, and surveys were excluded.
SYNTHESIS There is no well-validated clinical method for establishinga diagnosis of ankyloglossia. Five studies using different diagnostic criteria found a prevalence of ankyloglossia of between 4% and 10%. The results of 6 non-randomized studies and 1 randomized study assessing the effectiveness of frenotomy for improving nipple pain, sucking, latch, and continuation of breastfeeding all suggested frenotomy was beneficial. No serious adverse events were reported.
CONCLUSION Diagnostic criteria for ankyloglossia are needed to allow for comparative studies of treatment. Frenotomy is likely an effective treatment, but further randomized controlled trials are needed to confirm this. A reliable frenotomy decision rule is also needed.
The effect of ankyloglossia on breastfeeding has been a matter of controversy in the medical literature for 50 years.1 With the resurgence of breast-feeding, ankyloglossia has once again become an important clinical issue.2–6 The prevalence of ankyloglossia has been reported in several studies,5–9 but there is neither an accepted criterion standard nor clinically practical criteria for diagnosing the condition.9 This lack of standardized criteria for diagnosing ankyloglossia is one of the Canadian Paediatric Society’s main criticisms of research on this condition.10
Ankyloglossia in children can lead to a range of problems, such as difficulties breastfeeding, speech impediments, poor oral hygiene, and being embarrassed by peers during childhood and adolescence. About 90% of pediatricians and 70% of otolaryngologists believe that ankyloglossia rarely causes feeding difficulties; about 69% of lactation consultants believe that it frequently causes feeding difficulties, and an additional 30% believe it occasionally causes feeding difficulties.11 Ankyloglossia in infants is associated with a 25% to 60% incidence of difficulties with breastfeeding, such as failure to thrive, maternal nipple damage, maternal breast pain, poor milk supply, breast engorgement, and refusing the breast.2,3,7,8,12,13 Studies have shown that, for every day of maternal pain during the initial 3 weeks of breastfeeding, there is a 10% to 26% risk of cessation of breastfeeding.14 The ineffective latch caused by ankyloglossia could be one of the primary underlying causes of all of these problems.2,3,8,12,13
Infants with restrictive ankyloglossia cannot extend their tongues over the lower gum line to form a proper seal and must use their jaws to keep the breast in the mouth.2,3,8 An ultrasound study of breastfeeding in normal infants demonstrated that good tongue mobility is necessary for effective breastfeeding.15 In infants with ankyloglossia, this deficiency cannot be ameliorated by the usual positioning and latching techniques and might require surgical correction.2
The most common treatment of infant ankyloglossia is simple frenotomy. Frenotomy is accomplished by incising several millimeters into the lingual frenulum. This procedure is brief and usually bloodless and is described in detail in a recent position paper from the American Academy of Pediatrics on the effect of tongue-tie on breastfeeding.4 Hemostasis, if needed, is achieved by breastfeeding, which also lengthens the tongue and acts as an analgesic and antiseptic.2
Complications historically attributed to frenotomy include infection, hemorrhage caused by severance of the lingual artery, and asphyxia caused by the released tongue falling back into the airway.2,16 In recent years, there has been a renewal of interest in frenotomy as a treatment for ankyloglossia and an exploration of the complications associated with the procedure in the modern era, which are negligible.5,6,9 Given the current revival of interest in frenotomy, we thought a comprehensive review of the literature on ankyloglossia and frenotomy would be helpful. As this study is a systematic review of the literature and did not involve direct acquisition of patient data or affect patient care, ethics approval was not required.
DATA SOURCES
MEDLINE and CINAHL databases were searched from 1966 to 2006 using combinations of the key words ankyloglossia, tongue-tie, frenotomy, breastfeeding, breastfeeding problems, breastfeeding duration, latch, nipple trauma, pain, infant, and weight.
Abstracts of articles related to ankyloglossia were retrieved and read by 1 of the authors (L.M.S.). The reference sections of selected papers were examined to identify further relevant articles. Hazelbaker’s unpublished thesis17 was acquired by the authors.
We selected articles we deemed were relevant to diagnosis, prevalence, and surgical treatment of ankyloglossia. These articles were read by 2 of the authors (L.M.S. and P.F.). These authors independently abstracted data, discussed discordances, and reached consensus on the results.
All studies that included data on infants younger than 6 months, such as case reports, case series, retrospective studies, prospective controlled studies, and randomized controlled trials, were selected for detailed analysis. Articles that did not address ankyloglossia in relation to breastfeeding problems were excluded. Opinion pieces, literature reviews, studies without patient data, studies that did not focus on breastfeeding, position statements, and surveys were also excluded. We used modified criteria18 to evaluate the quality of the 6 studies addressing the effectiveness of frenotomy for treatment of ankyloglossia (Table 1).
SYNTHESIS
We found 183 articles during our initial search; 53 addressed ankyloglossia specifically. After exclusion criteria were applied, 5 studies describing the prevalence of ankyloglossia, 12 articles assessing diagnostic criteria for ankyloglossia, and 7 articles describing the effectiveness of frenotomy for treatment of ankyloglossia remained.
Diagnosis of ankyloglossia
Clinical criteria used to diagnose ankyloglossia are summarized in Table 2.2,3,5–9,11,12,17,19–21 Criteria used for identifying ankyloglossia varied greatly from paper to paper. Many authors used criteria based on the physical characteristics of infants’ oral anatomy. A commonly employed criterion was the frenulum being abnormally short and thick, which caused the tongue to become heart-shaped upon protrusion. Criteria also included signs of functional impairment, such as an inability to protrude the tongue past the gum line, and other indications of decreased tongue mobility. Some authors also cited the effect that ankyloglossia has on breastfeeding, such as causing maternal nipple pain and nipple trauma. None of these criteria have been validated. There is no accepted criterion standard test for ankyloglossia, and none of these studies prospectively compared its method against a proposed criterion standard. None of the studies assessed their diagnostic methods for internal and external validity.
Prevalence of ankyloglossia
The 5 studies that assessed the prevalence of ankyloglossia all used different diagnostic criteria and different ages of assessment for diagnosis (Table 35–9). This could explain the variation in prevalence from 4.2% to 10.7%.
Consequences of ankyloglossia
Mothers breastfeeding infants with ankyloglossia have more nipple pain than mothers feeding normal infants.7,9,18 The prevalence of nipple pain is between 60% and 80% in all nursing mothers during the early postpartum period.13,22,23 With normal infants, this pain is transient, peaks on the third day, and resolves spontaneously within 2 weeks.22 The prevalence of persistent nipple pain in breastfeeding women whose infants have ankyloglossia is between 36% and 80%. Only 3% of mothers of normal infants have intractable pain or difficulty getting their babies to latch at 6 weeks, but 25% of mothers of babies with ankyloglossia have these problems.7
Frenotomy
Most of the 7 studies on frenotomy were of poor methodologic quality, with a mean quality score of 24.4 (range 9 to 40) out of a possible 47 points (Table 42,3,5,6,8,12,19). The studies by Hogan et al,5 Ballard et al,8 Griffiths,6 and Masaitis and Kaempf3 had the highest scores. These 4 studies were larger and had more rigorous selection of patients and better descriptions of patients at baseline. There was only 1 randomized controlled trial of frenotomy.5 All these studies used different outcome measures to assess the effectiveness of frenotomy, including nipple pain, infant growth, tongue mobility, and successful breastfeeding. All the studies showed an improvement in recorded outcomes after frenotomy.
In the randomized controlled trial,5 27 of 28 mothers of infants with ankyloglossia who were randomized to frenotomy had reduced nipple pain and improved breastfeeding at 1 week, but only 1 mother out of 29 randomized to 48 hours of intensive intervention by a lactation consultant experienced these improvements. All the remaining mothers in the control group (28/29) chose to have their infants undergo frenotomy. A second study2 showed that intensive counseling and education on breastfeeding had not improved breastfeeding difficulties at 2 to 12 weeks in 10 of 13 infants with ankyloglossia. In a prospective non-randomized cohort study,6 80% of infants had improved feeding 1 day after frenotomy.
None of the studies we found described serious complications following frenotomy. All the studies showed a benefit from frenotomy (Table 52,3,5,6,8,12,19).
DISCUSSION
Our study has shown clearly that there is no accepted, widely used method for diagnosing ankyloglossia. The 1 standardized tool, the assessment tool for lingual frenulum function (ATLFF) developed by Hazelbaker,17 is too lengthy and complex for use in a busy clinic, and in 1 study, could not be used to evaluate more than 60% of infants being tested.9
Development of a concise, practical, standardized, validated tool for diagnosing ankyloglossia and a decision rule for frenotomy are important for further research. They would allow researchers to conduct further randomized controlled trials and also permit integrated analysis of data from these trials.
Not surprisingly the data on prevalence and treatment of ankyloglossia are also complicated by heterogeneity, not only in diagnosis but also in assessment of outcomes. Despite this complication, the data suggest that ankyloglossia is common, causes problems, and can be relieved in most cases by frenotomy.
The prevalence of pain in mothers breastfeeding infants with ankyloglossia is much higher than that reported in mothers breastfeeding normal infants and clearly presents a considerable problem in terms of continuing breastfeeding. Intensive breastfeeding support is often inadequate for relieving breastfeeding difficulties in babies with ankyloglossia.
Results of studies assessing the effectiveness of frenotomy showed that breastfeeding mechanics improved and maternal pain decreased after the procedure. None of the studies found any serious complications of frenotomy. Given the relatively high prevalence of ankyloglossia, the large proportion of mothers of these infants with nipple pain, the strong association between pain and stopping breastfeeding, and the generally acknowledged health risks associated with not breastfeeding, frenotomy could be of great use as a safe and effective early intervention for breastfeeding problems attributed to ankyloglossia.
Future research efforts should be aimed at establishing clinically practical and valid diagnostic criteria for ankyloglossia in infants. After these criteria are established, results of further randomized controlled trials would assist in deciding whether frenotomy reduces breastfeeding difficulties, increases duration and exclusivity of breastfeeding, and leads to improved growth in tongue-tied infants. The design of an ideal randomized controlled trial, however, would be limited by ethical constraints. It would be unethical to leave a control group of mothers of infants with ankyloglossia in pain given that current evidence strongly suggests that frenotomy would relieve their pain and that continued pain would put their infants at increased risk of premature weaning.
Limitations
This review is limited to articles available in English and indexed on MEDLINE and CINAHL and papers referenced in them. Limiting the search technique might have missed studies of non-surgical approaches to tongue-tie and might have led to an overestimation of the prevalence of breastfeeding difficulties associated with ankyloglossia. We recognize that the methodology of this comparative review is subjective, but without standardized diagnostic criteria, a more systematic review of the literature was not possible.
Conclusion
Given the evidence currently available, we propose that frenotomy be viewed as a safe, effective, and practical approach to treatment of breastfeeding difficulties in infants with ankyloglossia in whom alternative explanations for poor feeding and failure to thrive have been properly assessed.
Acknowledgment
This study was funded through the research and development funds of the Herzl Family Practice Center. We thank Alison Glaser, a research assistant in the Department of Family Medicine at McGill University in Montreal, Que; Francesca Frati, an Information Management Consultant for the Department of Family Medicine at Jewish General Hospital in Montreal; and A.K. Hazelbaker for allowing us to use her thesis, The assessment tool for lingual frenulum function (ATLFF): use in a lactation consultant’s private practice.
Notes
EDITOR’S KEY POINTS
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Ankyloglossia is a common finding in infants. Prevalence ranges between 4.2% and 10.7%.
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Mothers breastfeeding infants with ankyloglossia have more nipple pain than mothers breastfeeding normal infants. The prevalence of persistent pain in these women is up to 80%; about 25% have intractable pain or difficulty latching at 6 weeks.
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Studies show a positive benefit of frenotomy with no serious complications.
POINTS DE REPÈRE DU RéDACTEUR
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L’ankyloglosse est fréquente chez le nouveauné, sa prévalence étant de 4,2% à 10,7%.
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Les femmes qui allaitent un bébé avec ankyloglosse ont plus de douleur mamelonnaire que celles qui nourrissent un enfant normal. La prévalence de douleur persistante chez ces femmes peut atteindre 80% et dans 25% des cas, on observe des douleurs rebelles ou un verrouillage difficile à 6 semaines.
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Les études montrent que la frénotomie a des effets favorables sans complication sérieuse.
Footnotes
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This article has been peer reviewed.
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