By: Robyn Merkel-Walsh MA, CCC-SLP, COM®
The reported prevalence of ankyloglossia varies from <1 percent to 32.54 percent, depending upon the study population and criteria used to define ankyloglossia (Isaacsson, Messner & Armsby, 2017; de Castro Martinelli, Marchesan & Berretin Felix, 2018). Recently there has been an increased awareness and ongoing debate concerning ankyloglossia in regards to the impact on speech and the role of the speech-language pathologist (SLP) in regard to assessment and treatment (Kummer, 2005; Merkel-Walsh & Overland, 2018; Potock, 2017).
Since most of the research regarding ankyloglossia is focused on breastfeeding, SLPs do have enough information regarding the impact of tongue-tie on other functions, especially speech. Clinicians specializing in orofacial myofunctional disorders and /or oral motor function, consistently report that ankyloglossia impacts the placement of speech sounds leading to articulation deficits (Merkel-Walsh & Overland, 2018; Baxter, 2018). It would seem logical that since we need the tongue to articulate certain phonemes, if the tongue was altered in any way, then those lingual placements for speech could be problematic.
Kummer (2005) has stated that the tongue does not need much far for speech placements, and that there is virtually no evidence in the literature to establish a definite causal relationship between ankyloglossia and speech disorders, but Merkel-Walsh and Overland (2018) debate this based on varying placements of the tongue for speech sounds and the range during co-articulation of speech sounds. For example, lingual placement for /t/ with a high to medium height jaw phoneme (e.g. /i/), will be easier to achieve than /t/ paired with a low jaw phoneme (e.g. /æ/) (Merkel-Walsh & Rosenfeld-Johnson, 2011).
Emerging research such as case studies by Messner & Lalakea (2002), Walls, Pierce, Wang, Steehler, Steehler & Harley (2014), Meaux, Savage & Gonsoulin (2016) and Baxter & Hughes (2018) analyzed pre- and post-op speech clarity which is a good start to provoke larger studies. Since evidence based practice is a map including practice based evidence, it is important to consider the value of clinical data and small study /case study findings.
One of the most prominent studies linking ankyloglossia to speech disorders was in November of 2004, in The International Journal of Orofacial Myology (Marchesan, 2004). In this study, Marchesan looked at 1402 patients and various classifications of altered frenulum and speech. Out of the 1402 patients, 9% had a short or anterior restriction and 48.81% of that group had speech disorders, with /r/, /s/ and /z/ most prominent. The conclusion stated that an altered frenulum may predispose an individual to an accompanying speech sound disorder.
In the book Functional Assessment and Remediation of Tethered Oral Tissue(s), Merkel-Walsh & Overland (2018) describe in detail the possible impact of tongue-tie on each group of sounds. To understand how TOTs may be impacting speech sound production, we must go back to our foundations of phonetic placements. For example, back tongue side spread in needed for /r/, /∫/, /dʒ/ and /t∫/. TOTs may impact these sounds based on the retraction and lateral lingual margin elevation to clearly articulate the sounds. There may be limited tongue retraction with lateral wall tension resulting in fronting, distortions or omissions.
Please read this important study and consider it when reading “ankyloglossia does not impact speech” or there is “no correlation”.