Overview of the methodological weaknesses in the research concerning tongue-tie and upper lip-tie
“There are no reliable long-term follow-up studies on the effects of the surgery on both breastfeeding and speech.”
Classic tongue-tie has been overlooked and left untreated for decades. The work of tongue-tie and lip-tie activists in Australia, the USA, and UK today has four positive outcomes. Their work has highlighted the importance of:
Prompt frenotomy for a classic tongue-tie;
Careful oral and oromotor assessment as part of infant feeding support in the clinic, and the need to develop useful assessment tools;
The connection between breastfeeding problems and unsettled babies;
Research into the clinical support of breastfeeding and related unsettled behaviour.
Both the 2014 and 2015 systematic reviews which separately examine all the existing evidence concerning frenotomy or frenectomy in babies with breastfeeding difficulties have found only weak (‘Level D’) evidence to suggest it helps.
Existing research has the following problems:
Definitions of tongue-tie are inconsistent and confused. Often, both classic and ‘posterior’ versions are lumped into the one broad category, ‘tongue-tie’, without attempts to clarify further. This lack of definition is likely to underestimate the positive effects of frenotomy for classic tongue-tie, and overestimate the positive effects of frenectomy for what is being diagnosed as ‘posterior’ tongue-tie (but which is likely to be normal anatomic variant, as is 'upper lip-tie').
Definitions of accompanying breastfeeding difficulties are inconsistent and confused.
The nature of the surgery is inconsistently reported. The techniques used and depth of the cut are not defined.
Commonly used diagnostic tools, including the popular Hazelbaker Assessment of Lingual Frenulum Function (ATLFF), are flawed. For example, a well-conducted 2008 study of 148 newborn babies concluded that the ATLFF is not reliable. http://www.ncbi.nlm.nih.gov/pubmed/17276561
Effects of the surgery are confounded by breastfeeding support, which is generally offered around the same time, although the nature of this support is not defined.
There are no comparisons with the effects of the passage of time.
The placebo effect is difficult to measure.
There are no reliable long-term follow-up studies on the effects of the surgery on both breastfeeding and speech.
For more information, please see an overview article in The Conversation or an in-depth analysis with comprehensive citations in 'Tongues tied about tongue-tie' in the Griffith Review Online March 2016.