Lip-tie and tongue-tie are frequently mentioned in the same breath, and for good reason — they often occur together and get evaluated at the same visit. But they’re two distinct conditions affecting different tissue, with their own signs, their own diagnostic considerations, and sometimes different treatment timelines. If you’re trying to figure out which one you’re noticing in your child — or whether it’s both — here’s how to tell them apart.
This article is for general education and isn’t a substitute for an in-person evaluation.
What Is Lip-Tie?
Lip-tie refers to a restrictive or tight labial frenulum — the band of tissue connecting the upper lip to the gums above the front teeth. Every baby is born with some version of this frenulum; lip-tie describes cases where it’s thick, tight, or attached in a way that restricts normal lip movement, particularly the ability to flange the upper lip outward during feeding.
Diagnosing lip-tie is less standardized than it might seem. Several classification systems exist — including Kotlow’s system, the Stanford classification, and others — that categorize lip-tie based on where the frenulum attaches relative to the gumline. Research has found that these appearance-based systems can be difficult to apply consistently between examiners, since normal variation in labial frenulum anatomy is common, and not every visually prominent frenulum causes a functional problem. This is part of why some newer classification approaches have started incorporating actual lip function and mobility, not just anatomical appearance, to better capture what’s clinically relevant.
What Is Tongue-Tie?
Tongue-tie, or ankyloglossia, involves the lingual frenulum — the band connecting the underside of the tongue to the floor of the mouth. When it’s too short, thick, or tight, it restricts tongue mobility, which can affect feeding, speech, and oral function depending on severity and type. We cover the full diagnostic picture, including the major grading systems used for tongue-tie specifically, in Tongue-Tie Grading: How Dentists Diagnose a Tongue-Tie.
Signs and Symptoms: How to Tell Them Apart
Signs more specific to lip-tie:
- Difficulty flanging the upper lip outward during breastfeeding, sometimes resulting in a clicking sound or milk leaking from the corners of the mouth
- A visible gap between the upper front teeth as teeth erupt (though this can have other causes too)
- Lip fatigue or the upper lip curling inward during feeding
Signs more specific to tongue-tie:
- A heart-shaped or notched appearance when the tongue is extended
- Difficulty lifting the tongue to the roof of the mouth or extending it past the lower lip
- Speech sound difficulties in older children, particularly sounds requiring the tongue tip to reach the palate
Signs common to both:
- Poor or painful latch during breastfeeding
- Long, exhausting feeding sessions
- Slow weight gain
- Nipple pain or damage for breastfeeding parents
- General feeding frustration for both baby and parent
Because these two conditions frequently co-occur and share several overlapping symptoms, a feeding difficulty alone doesn’t tell you which one — or whether both — are involved. That’s exactly why a proper evaluation looks at both structures rather than assuming based on symptoms alone.
Why Evaluation Should Involve More Than a Visual Exam
Given how much normal variation exists in labial and lingual frenulum anatomy, and how inconsistently appearance-based grading has performed in research, a thorough evaluation goes beyond simply looking under the lip and tongue. It should assess actual function — how well the lip flanges, how the tongue moves during specific tasks, and critically, how feeding is actually going. This is where coordinated care matters: our Lactation & Infant Feeding Support team works alongside our dental providers to assess the full feeding picture, not just frenulum appearance in isolation.
For the broader context on what a frenectomy treats, how ties are diagnosed, and how we approach the decision overall, our pillar guide covers it in full: What Is a Frenectomy? Tongue-Tie and Lip-Tie Explained.
Treatment Considerations for Lip-Tie vs. Tongue-Tie
When treatment is indicated, both conditions are addressed with a frenectomy — a lingual frenectomy for tongue-tie, a labial frenectomy for lip-tie, and sometimes both performed in the same visit if both are contributing to feeding difficulty. We use laser technology for many of these releases, which you can read more about in Laser Frenectomy & BabyLase: Why We Use It. Recovery expectations are similar for both procedures; our day-by-day recovery guide walks through what to expect regardless of which tie was treated.
One important treatment consideration specific to lip-tie: because normal frenulum anatomy changes as a child grows, and because appearance alone doesn’t reliably predict functional impact, treatment decisions for lip-tie in particular should weigh actual feeding difficulty carefully rather than defaulting to treatment based on visual appearance alone.
Getting a Clear Answer
If your baby is struggling with feeding and you’re not sure whether lip-tie, tongue-tie, or something else entirely is the cause, the most useful next step is a coordinated evaluation that looks at anatomy and function together. Schedule a consultation with our team to get a clear, functional assessment rather than guessing based on appearance.
References
- Santa Maria C, Aby J, Truong MT, Thakur Y, Rea S, Messner A. The Superior Labial Frenulum in Newborns: What Is Normal? Clinical Pediatrics. PubMed-indexed. https://journals.sagepub.com/doi/10.1177/2333794X17718896
- Effectiveness of tongue-tie assessment tools in diagnosing and fulfilling lingual frenectomy criteria: a systematic review. PubMed / PMC, National Library of Medicine. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9796854/