Three words get used almost interchangeably online, and they describe three different things. Cleft chin, butt chin and chin dimpling look similar in a photograph and have entirely different causes underneath. One is a bone feature you were born with, one is a soft tissue variant of the same, and one is a muscle behaviour that happens on expression.
Which one you have decides what, if anything, is worth doing about it, and it also decides who you should see.
Written and clinically reviewed by Dr Ibrahim Hawli, MBBS. Tajmeel Cliniq, Glenroy, Melbourne.
Why these three get confused
All three produce a similar visual: a vertical line, groove or dimple in the middle of the chin. On a photograph, particularly a small one, they are hard to tell apart.
Anatomically they are not the same thing at all. The chin is built from three layers: bone at the base, a small muscle called the mentalis sitting on top of the bone, and skin over both. A depression in the chin can come from any of the three layers.
- Bone: a groove in the front of the mandible produces a cleft chin
- Muscle attachment pattern: how the mentalis muscle inserts into the skin produces the butt chin variant
- Muscle activity: overactivity of the mentalis on expression produces the dimpling seen when speaking or emoting
Understanding which layer is producing your specific feature is the entire point of this article, because the answer changes what can and cannot be done.
Cleft chin: a bone feature you were born with
A true cleft chin is a genetic anatomical variant of the mandible, the lower jaw bone. During development, the two halves of the mandible fuse at the midline in the first year of life. In some people, that fusion leaves a visible groove or dimple in the front of the chin. In others, the fusion is smooth and no groove is visible.
Key features:
- Present from birth or emerges as facial structure develops in early childhood
- The depression is visible at rest, not only when smiling or speaking
- Palpating the chin with your fingers, you can feel the groove in the bone underneath
- Often runs in families, because it is genetic
- Does not change with muscle activity or expression
How to tell if yours is a true cleft chin: relax your face completely. If the depression is clearly there at rest, and you can feel a firm groove under your fingertip pressing on the chin, that is likely a bone-based cleft chin.
What can be done: the honest answer is very little, and this is a scope conversation. A cleft chin is a bone feature. Changing bone contour is orthognathic or maxillofacial surgery, and it is not a cosmetic procedure that can be reversed if you change your mind. Most people who ask about their cleft chin are considering whether to reduce it. For the small number where the anatomy is significant enough to warrant assessment, that is a conversation with a maxillofacial surgeon, not a cosmetic clinic.
For most people the answer is that a cleft chin is part of the anatomy you have and it is not going anywhere. Many people grow to like theirs, and it is worth pausing before considering anything drastic.
Butt chin: the same feature, softer
Butt chin is a colloquial term for a cleft chin that looks softer and more rounded, with the two halves of the chin appearing as slightly separated round shapes rather than a sharp vertical groove.
Anatomically it is often the same underlying feature as a cleft chin, but the way the soft tissue sits over it produces a different appearance. The soft tissue difference relates to how the mentalis muscle inserts into the skin and how much subcutaneous fat is present.
Key features:
- Also present from birth
- Also visible at rest
- The appearance is softer than a sharp cleft
- Often more prominent in certain lighting or when the chin is prominent from a specific angle
What can be done: the same limits apply as with a true cleft chin, because the underlying feature is bone. Cosmetic assessment might contribute to how the soft tissue reads over the bone in a very limited way, but the fundamental shape is set. Most consultations that begin with “can you fix my butt chin” end with an anatomical explanation and no recommendation for anything to be done.
That is not a failure of the consultation. It is the correct answer to the question.
Chin dimpling: the muscle behaviour one
This is entirely different from the two above, and it is often mistaken for them.
Chin dimpling is the appearance of small dimples or a pebbly texture in the skin of the chin, appearing specifically when the chin is engaged. It happens when speaking, when pursing the lips, when smiling in some patterns, and when frowning.
Anatomically this is produced by the mentalis muscle. The mentalis is small, cone-shaped, and it sits on the front of the chin. Unusually for facial muscles, it inserts directly into the skin rather than into other muscles or bones. When it contracts, it pulls the skin from below, and this produces the visible dimpling.
Key features:
- Not present at rest, at least not obviously
- Appears when you speak, purse your lips, or make certain expressions
- Sometimes described by patients as “orange peel” texture on the chin
- Often noticed by patients when they smile or in photographs of themselves speaking
- Can become more prominent with age as skin quality changes
How to tell if yours is chin dimpling: relax your chin completely and look in a mirror. Is your chin smooth? Now purse your lips as if you are about to whistle, or push your lower lip forward as if grimacing. Do small dimples appear on the front of your chin? That is mentalis activity producing dimpling.
Bring what you observed to any assessment. It is diagnostic in a way that photographs are not.
What can be done: unlike the two bone-based features above, this one is muscle-related and there are approaches that address the muscle activity. That is a cosmetic assessment conversation, and it belongs on the chin texture concern page rather than in a general anatomy article.
The important point for this article: if your concern is dimpling on expression rather than a groove at rest, you are dealing with a muscle behaviour, not a bone feature. It has a different anatomy, a different assessment, and different options.
A summary of how to tell them apart
Stand in front of a mirror in even light and follow these steps.
Step 1. Relax your face completely. Look at your chin.
Step 2. Is there a clear vertical groove, dimple or divot visible right now, with your face relaxed?
- Yes, sharp vertical groove → likely a cleft chin (bone feature)
- Yes, softer rounded impression → likely a butt chin variant (also bone-based, softer soft tissue)
- No, chin looks smooth → move to step 3
Step 3. Purse your lips as if to whistle, or push your lower lip forward. Look at the front of your chin.
- Small dimples or pebbly texture appears → chin dimpling (mentalis muscle activity)
- Chin stays smooth → likely neither feature is prominent, and any concern may be about something else entirely
Step 4. With one fingertip, press firmly into the centre of your chin at rest.
- You can feel a firm groove in the bone underneath → confirms bone-based
- You cannot feel any bony groove → the feature is soft tissue rather than bone
This ten-second self-assessment is more informative than most consultations that skip it.
Which practitioner sees which
Bone-based cleft chin, and you are considering whether to reduce it: maxillofacial surgeon. It is a bone procedure, and it needs surgical assessment. A cosmetic medical practice cannot address it.
Butt chin variant: same as above. Any significant change to the bone shape underneath requires surgical assessment. Cosmetic assessment might contribute to how the soft tissue reads in narrow circumstances but cannot change the underlying feature.
Chin dimpling on expression: cosmetic medical assessment. This is a soft tissue and muscle activity concern that a cosmetic practice can genuinely address. Read the chin texture concern page for the details.
None of the above but the chin looks off to you: worth a consultation to work out what is actually being noticed. Sometimes the concern turns out to be chin projection, chin width, or asymmetry rather than any of the three features above. Each of those has its own answer.
Why the words get mixed up
The reason there is so much confusion online is that most content is written from a photograph rather than from an examination. A photograph of a resting face can show a soft chin dimple that is a bone cleft, and a photograph of an expressive face can show muscle-based dimpling that looks similar. Without palpating the bone, without watching the face move, and without a functional assessment, the distinction is genuinely hard to make.
A proper assessment in person takes about thirty seconds and settles it definitively. It also often changes what the patient thought they wanted.
In summary
- Cleft chin, butt chin and chin dimpling look similar and are three different things
- Cleft chin is a bone feature present from birth, palpable as a groove in the mandible
- Butt chin is the same bone feature with softer overlying soft tissue
- Chin dimpling is muscle activity on expression, produced by the mentalis contracting
- Bone features cannot be changed by a cosmetic assessment; that is surgical scope
- Muscle-based dimpling is a genuine cosmetic assessment topic
- A ten-second self-check in the mirror tells you which one you are looking at
Knowing which of the three you have decides whether an assessment is worth booking, and if it is, which kind of practitioner to book with.
If your concern is chin dimpling on expression, you can book a consultation with Dr Ibrahim Hawli. If your concern is a bone-based cleft chin and you are considering reducing it, a maxillofacial surgeon is the appropriate practitioner.
Read the main concern page: Chin texture and mentalis dimpling
About the author: Dr Ibrahim Hawli, MBBS, is a registered medical practitioner at Tajmeel Cliniq in Glenroy, Melbourne. Ahpra registration MED0002627622, verifiable on the public register.
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