SJ-20 (Jiao Sun) Angle Vertex

What does SJ-20 Jiao Sun do?

SJ-20 benefits the ears, benefits the teeth, gums and lips, and clears heat — and it is the only point on this channel’s ear run whose action names the mouth.

• Benefits the ears — the action shared across the whole run, from SJ-17 to SJ-21
• Benefits the teeth, gums and lips — unique to this point on the run
• Clears heat

It is a Meeting Point of the San Jiao, Small Intestine and Gallbladder channels — three pathways, the same designation our SJ-22 He Liao record carries a short distance away. The side of the head is where several channels converge, which is why so many points there hold multi-channel classifications.

SJ-20 anchors the measuring system for the two points behind the ear. Our records place SJ-18 Chi Mai at one third and SJ-19 Lu Xi at two thirds of the distance along a curved line drawn from SJ-17 Yi Feng, behind the earlobe, to SJ-20, at the ear apex. That is an elegant arrangement and an unusual one: two points located as fractions of a curve rather than by cun. It works because both ends are firm landmarks — and SJ-20 is one of them.

On the name. “Jiao Sun” means Angle Vertex. Jiao is a corner or angle — the corner of the head above the ear — and sun has been read as a grandchild or a minor branch, taken to refer to the fine connecting vessels described in this region. Our record holds Angle Vertex, and other renderings circulate; this page does not choose between them.

Source: Sacred Lotus sources & references (channel, category, action, location and translation records; the SJ-17, SJ-18, SJ-19, SJ-21 and SJ-22 records queried and the curved-line construction confirmed against our own data), cross-referenced against multiple online sources.

What is SJ-20 Jiao Sun used for?

SJ-20 is used for tinnitus, for red painful swollen eyes, for swollen gums and toothache, and for parotitis. Our own indication record is reproduced here in full.

• Tinnitus
• Redness, pain and swelling of the eye
• Swelling of the gum
• Toothache
• Parotitis

An honest note, and the last entry needs the most care. “PAROTITIS” MEANS INFLAMMATION OF THE PAROTID SALIVARY GLAND, WHICH SITS DIRECTLY BENEATH AND IN FRONT OF THE EAR — and its classic cause is MUMPS.

• Mumps is a viral infection preventable by vaccination (the MMR vaccine). It can cause meningitis, deafness, and inflammation of the testicles, ovaries or pancreas. It requires medical assessment and, in many countries, notification to public health authorities.
• Bacterial parotitis — a hot, tender, swollen gland, often with fever and pus at the duct — needs antibiotics urgently.
• Any persistent or one-sided swelling in front of the ear requires medical assessment, since parotid swelling also has non-infectious causes including tumours.

This record documents a classical indication and makes no claim that acupuncture treats parotitis or mumps. The entry is in the historical literature because the condition was common and its swelling sits exactly where this point does.

The other entries, briefly. A red, painful eye requires assessment — some causes are sight-threatening and urgent. Toothache and swollen gums need dental assessment; a dental infection with facial swelling and fever is a medical emergency. New or one-sided tinnitus requires assessment.

Why teeth and gums, on a point above the ear. Our record’s action names them directly, and the anatomy is close: the jaw joint and the muscles of chewing lie just below and in front. Our ST-42 record sets out the channel logic for the upper teeth and LI-04 is the classical distal point for the lower — SJ-20 is a local point for the region rather than a channel-specific one.

How it is combined. With SJ-17 Yi Feng behind the earlobe — the great ear point of this channel, and directly over the parotid region. With SJ-21 Er Men, SI-19 Ting Gong and GB-02 Ting Hui in front of the ear. With LI-04 He Gu distally for the face and teeth. All held here.

Source: Sacred Lotus sources & references (indication and action records; the GB-02, LI-04, SI-19, SJ-17, SJ-21 and ST-42 records queried from our own data), cross-referenced against multiple online sources.

Where is SJ-20 Jiao Sun located?

SJ-20 is on the side of the head, directly level with the tip of the ear when the ear is folded forwards.

• Level with the apex of the ear, with the ear folded forwards
• SJ-19 Lu Xi and SJ-18 Chi Mai lie behind the ear on the curved line down to SJ-17
• SJ-21 Er Men and SJ-22 He Liao lie in front of and below it

This is a landmark the reader creates rather than finds, and that makes it unusually reliable. Folding the ear forward produces a definite apex, and the point is level with it. No counting, no proportional measurement, no bony feature that varies between people — the ear is its own ruler. Very few locations in this library work that way; our ST-02 record requires the eyes looking straight ahead and our SJ-11 record the elbow flexed, but those adjust a landmark rather than making one.

And SJ-20 anchors two other points. Our SJ-18 and SJ-19 records place those points at one third and two thirds along a curved line running behind the ear from SJ-17 to this point. So an error in locating SJ-20 propagates to both — and conversely, getting it right fixes all three. It is worth locating carefully for that reason alone.

A caution about hair. This point lies within the hairline, where landmarks are hidden and the temporal region is easy to misjudge by eye. The folded ear remains visible and usable regardless.

On the name. “Jiao Sun” — Angle Vertex, the angle being the corner of the head above the ear.

Source: Sacred Lotus sources & references (location and translation records, retained unchanged including the folded-ear requirement; the SJ-17, SJ-18, SJ-19, SJ-21, SJ-22, ST-02 and SJ-11 records queried from our own data).

• A Manual of Acupuncture (p. 410): On the side of the head, directly level with the apex of the ear when the ear is folded forwards.
• Chinese Acupuncture and Moxibustion (p. 208): Directly above the ear apex, within the hair line.

How is SJ-20 Jiao Sun needled?

Our own record states SUBCUTANEOUS insertion — the needle laid along under the skin — to roughly 0.3–0.5 inch, with moxibustion applicable. What follows is a neutral record of what the reference literature documents. It is not instruction, and this page does not teach technique.

• Angle and depth as recorded: subcutaneous (transverse), 0.3–0.5 inch — the same insertion our records give across the scalp generally, on the Governing Vessel and on the Bladder channel’s BL-03 to BL-09 run. SJ-18 behind the ear is recorded the same way; SJ-19 is oblique and SJ-21 perpendicular, so the angles differ point by point around the ear.
• Moxibustion: recorded as applicable.
• Regional anatomy: the temporalis muscle and its fascia lie beneath thin skin; the superficial temporal artery and vein and the auriculotemporal nerve ascend in front of the ear nearby; the temporal bone lies beneath.

Why subcutaneous, and why that is the whole safety story. There is bone beneath the temporalis, so the transverse angle is what the anatomy permits rather than a stylistic choice. This is a low-hazard point in that specific sense: no cavity, no organ, no major vessel at the point itself. The scalp is richly vascular and bleeds readily, which is a nuisance rather than a danger.

The arterial caution belongs to the neighbour, not here. Our SJ-22 He Liao record, a short distance in front, opens with “avoid puncturing the artery” and gives only 0.1–0.3 inch, because the superficial temporal artery is the very structure its location uses. SJ-20’s record carries no such caution, and this page does not import one — nine points in the library carry an explicit arterial caution, counted by query, and SJ-20 is not among them. The vessel is still in the region, which is why the anatomy is stated.

What is not claimed. No study measuring a safe depth at SJ-20 could be located, and none is borrowed. Neither measured-depth study this library uses reaches the head. No case report naming SJ-20 was located.

Source: Sacred Lotus sources & references (needling record, retained unchanged, and the SJ-18, SJ-19, SJ-21 and SJ-22 recorded angles and depths compared; every needling record queried and the nine arterial cautions counted), cross-referenced against multiple online sources; regional anatomy from standard anatomical description.

Is there research on SJ-20, and what should a reader know?

No trial isolates SJ-20. Where the point appears it is one component of an ear, headache or facial protocol, and a study that includes a point in a protocol is not evidence about that point.

A caution specific to the scalp. “Scalp acupuncture” is a distinct modern system with its own named zones and its own trial literature, and it is not the same thing as the classical channel points on the head. Searches for evidence about points in this region return those trials, and they are not evidence about SJ-20.

What this page can state with confidence. SJ-20 is located by folding the ear forward — a landmark the reader creates, so it does not vary with hairline, vertebral count or proportion. It anchors two other points: our SJ-18 and SJ-19 records place those at one third and two thirds along a curved line from SJ-17 to this point, so locating it accurately fixes all three. It is a meeting point of three channels. And it is the only point on this channel’s ear run whose action names teeth, gums and lips.

The parotitis warning is the operative content on this page. Swelling in front of the ear is a medical matter — mumps is vaccine-preventable and can cause deafness and meningitis; bacterial parotitis needs urgent antibiotics; and persistent one-sided swelling has other causes including tumours. No acupuncture claim is made or implied.

A note on searching for it. “SJ 20”, “TE 20”, “TB 20” and “Jiaosun” searches return protocol trials and unrelated material — and this channel is coded three ways across the literature: SJ, TE and TB. Our library uses SJ-. Any claim attached to this point should be checked against what a study actually used.

Source: Sacred Lotus sources & references (category, action, indication, location and needling records; the SJ-17 to SJ-22 run compared and the curved-line construction confirmed against our own data).