Chengjiang

What is CV24?

CV24 (Chengjiang) is a Conception Vessel point in the small hollow in the midline of the chin, just below the centre of the lower lip.

The pinyin name Chengjiang is usually translated as Sauce Receptacle or Container of Fluids, a nod to the dip where liquid would gather if it ran down the chin. It is the last point of the Conception Vessel, the midline channel that runs up the front of the body. Classical texts also describe it as a meeting place of that channel with the Stomach, Large Intestine and Governing Vessel pathways, which is why it appears so often in traditional work on the mouth and jaw.

In tradition, CV24 is reached for with facial paralysis, a mouth pulled to one side, toothache, sore gums, drooling, swelling of the lower lip, and sometimes sudden loss of voice. It is taught in essentially every acupuncture curriculum, so its traditional standing is high.

Here is the honest verdict on the evidence. There are no good human trials of finger pressure at CV24 for any of these uses. The point turns up inside multi-point acupuncture protocols for facial palsy, but those studies were mostly small, unblinded and poorly reported, so they cannot tell us what CV24 itself did. Research on acupressure in general is similar: small groups, no real placebo, short follow-up.

Two things are worth saying plainly once, because they apply to this whole page. Long traditional use is not evidence that a point works, and it is not evidence that it is safe either. Both have to be judged separately, from what has actually been measured and from what sits under the skin.

What CV24 can reasonably offer a layperson is a cheap, low-risk minute of gentle self-massage on a tense jaw or chin. It is not treatment for a nerve injury, an infected tooth or a sudden facial droop, and it should never delay care for those.

Where is CV24 and how do you find it?

CV24 sits in the centre of the chin crease, the small dip in the midline between your lower lip and the point of your chin.

• Start at the midline. Run a fingertip down from the centre of your nose, over the centre of your lips. Keep to that centre line as you move onto the chin.
• Find the crease. Just below the lower lip there is a shallow horizontal groove, called the mentolabial sulcus. It is easiest to feel if you relax your lips rather than pursing them.
• Feel for the hollow. Where that groove crosses the midline, there is a small soft depression. That depression is CV24.
• Check against the bone. Press gently straight back and you will feel the hard front of the lower jaw just under the skin. CV24 lies over bone, with very little tissue between.
• Confirm with movement. Open and close your mouth slowly. The point stays put in the crease, while the lip moves above it.

In traditional measurement, CV24 is described as being in the depression at the centre of the mentolabial groove. No thumb-width count is really needed, because the crease itself is the landmark. If you want a rough figure, the hollow sits roughly one finger-width below the border of the lower lip on most adults.

Two neighbours cause confusion and are worth ruling out. ST4 sits out at the corner of the mouth, not in the midline. ST5 is further back, on the lower edge of the jaw in front of the chewing muscle. If your finger has drifted sideways off the centre line, you are no longer on CV24.

Everything described here is self-applied finger pressure on the surface. Nothing on this page involves needles, depth or any skin-breaking technique.

How do you apply pressure to CV24?

1. Wash your hands. You are working next to your mouth, so clean fingers matter. Check the skin first for cuts, spots, blisters or a cold sore.
2. Sit and settle. Sit upright with your jaw loose and your teeth slightly apart. A clenched jaw makes the crease hard to feel.
3. Place one finger. Use the flat pad of your index or middle finger, not the nail. One finger is enough for a point this small.
4. Press gently straight back. Aim your pressure toward the chin bone behind the hollow. This area is thin and sits directly on bone, so use light pressure, around three out of ten.
5. Hold or circle. Either hold steady for 30 to 60 seconds, or make small slow circles for about a minute. Breathe normally throughout.
6. Rest and repeat. Release, wait a few seconds, and repeat up to two or three times. Two or three short sessions a day is plenty.
7. Support the jaw if it helps. Cup your chin in the other hand so your head is not pushed backward as you press.

A reasonable sensation is mild local pressure or a dull ache that fades when you let go. That is the ceiling. CV24 is not a point to lean on hard.

Stop straight away if the pressure causes sharp pain, numbness, pins and needles spreading into the lip or chin, bleeding gums, or pain in a tooth. Stop too if the skin reddens and stays sore afterwards.

Do not press through a dental plate, brace or a tooth that already hurts. If you have had recent dental or jaw surgery, leave the area alone until your dentist or surgeon says it is healed. Finger pressure is the only technique described here.

What is CV24 traditionally used for?

• Facial paralysis and a mouth pulled to one side. This is the best known traditional use of CV24, and the point appears in many acupuncture protocols for Bell's palsy. The human research is weak: trials were small, used many points at once, and rarely blinded, so no effect can be pinned to CV24.
• Toothache and sore gums in the lower front teeth. Classical texts list CV24 for pain in the lower jaw and gums. There is no trial testing finger pressure here for dental pain. Toothache has a physical cause that pressure does not fix, so a dentist is the right answer.
• Drooling and excess saliva. Traditionally framed as the point for fluid gathering at the chin. Modern evidence for this is essentially absent, with no controlled human studies of acupressure at CV24 for drooling.
• Jaw and chin tension. Many people find a minute of gentle self-massage around the chin crease relaxing, especially if they clench. That is plausible as simple soft-tissue relief rather than a channel effect, and it has not been formally tested at this point.
• Swelling or numbness of the lower lip and chin. Listed in older sources alongside facial problems. No useful human research exists, and new numbness in the lip always needs medical assessment first.
• Sudden loss of voice and mental restlessness. These appear in classical indication lists for CV24. They reflect channel theory rather than measured outcomes, and there is nothing in the modern literature supporting them.

Taken together, CV24 is a high-standing traditional point with a very thin modern evidence base. Pressing it gently is low-risk and may feel pleasant, but no outcome should be expected from it.

If a symptom on this list is new, one-sided, or getting worse, treat that as a reason to be assessed rather than a reason to press harder.

Are there tips for using CV24 effectively?

• Relax the jaw first. Let your teeth part slightly and your lips rest together without pressing. The chin crease is much easier to find on a loose jaw than a clenched one.
• Use a mirror the first few times. Checking that your finger is on the midline, below the lip and above the point of the chin, trains your aim quickly.
• Keep pressure light. There is bone directly under thin skin here. Light contact gives you everything the point has to offer, and heavy pressure only bruises.
• Keep sessions short. A minute at a time, two or three times a day, is more sensible than ten minutes of grinding on one spot.
• Pair it with jaw release. Gentle massage of the chewing muscles at the angle of the jaw, plus slow mouth opening, usually does more for clenching than a single point.
• Mind your nails. Short nails and the flat pad of the finger prevent scratches on facial skin that marks easily.
• Keep the skin clean and dry. Wipe away any balm or makeup first, so your finger does not slide off the hollow.
• Write down what happens. Note the symptom score before and after for a week. Self-massage benefits fade fast, so a simple log tells you whether anything real is changing.
• Stop on the day it hurts. If the area is tender, give it a rest rather than pushing through. A sore chin is a reason to pause, not to press harder.
• Use it alongside care, not instead. If a dentist, doctor or physiotherapist is already treating the problem, CV24 pressure is an optional extra and nothing more.

One last practical point. If you are using CV24 because of a facial droop, the priority is a medical assessment of why the droop happened. Self-massage can wait until that is sorted.

What do people get wrong with CV24?

• Expecting a cure. The commonest error is treating CV24 as a fix for facial palsy or toothache. No acupressure point cures either, and believing it does delays proper treatment.
• Drifting off the midline. People slide sideways and end up near the corner of the mouth, which is ST4, or back along the jaw at ST5. CV24 is strictly in the centre line.
• Pressing on the lip. Landing on the soft red of the lower lip instead of the hollow below it. The crease, not the lip, is the landmark.
• Sliding to the chin point. Going too low onto the rounded prominence of the chin. CV24 sits above that, in the dip.
• Using far too much force. The chin has little padding over bone. Hard pressure gives bruising, sore gums and a tender jaw, not better results.
• Pressing over broken skin. Working over a cold sore, a popped spot, a shaving cut or a graze risks spreading infection across the face.
• Pushing on a painful tooth. Driving pressure into an aching lower tooth or an inflamed gum makes things worse and misses an abscess that needs a dentist.
• Ignoring new numbness. Treating a numb lip or chin as a point to massage rather than a symptom to report. New numbness there needs checking.
• Using it after recent surgery. Pressing near a healing chin, jaw or dental site before it is cleared can disturb the repair.
• Overdoing the schedule. Long, repeated sessions on a small facial point simply irritate the skin. Short and gentle beats long and firm.
• Reading tradition as proof. Assuming that a point taught for centuries must be proven, when the human research behind CV24 is almost non-existent.

What does the research on CV24 actually say?

There is no published human trial testing finger pressure at CV24 on its own, for any condition. That is the plain starting point.

Where CV24 does appear in research, it is as one point among many in acupuncture protocols for facial paralysis, usually Bell's palsy. Those trials were run mainly in East Asia, often with small numbers of patients, no credible sham control, and short follow-up. Because every arm received a whole combination of points, none of them can say what CV24 contributed.

Systematic reviews have looked at this body of work, including Cochrane reviews of acupuncture for Bell's palsy. Their conclusion has been consistent: the trials were too small and too poorly reported to show whether acupuncture helps recovery, and better studies are needed. That is a verdict about the whole protocol, not about CV24, and it is not a positive result.

For the other traditional uses of CV24, such as drooling, lower toothache, lip swelling or loss of voice, no useful human research was found at all. That does not mean the point has been tested and failed. It means nobody has run the study.

It is worth knowing how the wider acupressure literature looks, for comparison. Most acupressure trials are small, unblinded and measure outcomes over days rather than months. A few points do better than that. PC6 and nausea is the clearest example in the field, with repeated controlled trials supporting a genuine effect on sickness after surgery and in pregnancy. CV24 has nothing approaching that.

What this means for a reader is simple. Treat CV24 as a traditional point with high standing and almost no measured effect. Gentle pressure is cheap and low-risk, so trying it costs little. Just do not let it substitute for a dentist, a doctor or a physiotherapist, and do not expect it to change the course of a nerve problem.