What D7870 means

D7870 covers an arthrocentesis (of the TMJ). "D" is dental, "78" is this oral surgery (TMJ) group, and "70" is this arthrocentesis. 'Arthro-' means joint and '-centesis' means puncture/aspiration (inserting a needle); so an arthrocentesis is the needle puncture of a joint — here, to flush/irrigate (lavage) the joint. The procedure inserts needles into the upper joint space and flushes it with fluid (e.g., sterile saline/lactated Ringer's), washing out the joint — without open surgery. So D7870 is the minimally invasive needle lavage of the TMJ.

So it's flushing out the jaw joint with needles (a minimally invasive lavage) — done for certain TMJ disorders to wash out the joint, reduce inflammation, and improve movement.

An arthrocentesis is used for certain TMJ conditions, classically: acute closed lock / limited opening — where the disc is displaced and the jaw is 'stuck' with limited opening (an acute disc displacement without reduction); the lavage (sometimes with manipulation/hydraulic pressure) can free the restricted joint, break up minor adhesions, and improve opening; joint inflammation/pain — washing out the joint removes inflammatory mediators and debris from the joint fluid, which can reduce inflammation and pain; and other TMJ internal derangement/arthralgia not responding to conservative care. The technique: needles are placed into the upper joint space; fluid is flushed through (entering one needle, exiting the other), irrigating the joint; sometimes the joint is distended and the jaw manipulated to improve mobility; and a medication (e.g., a corticosteroid or hyaluronic acid) may be injected at the end (an addition to the lavage). It's minimally invasive (needles, not an incision), often done under sedation or general anesthesia (sometimes local), as the least invasive of the surgical TMJ procedures — frequently tried before more invasive options (arthroscopy or open surgery). It's performed by an oral and maxillofacial surgeon. This code is in the TMJ group (D7810-D7899). TMJ-related coverage varies. Documentation of the condition and the procedure supports the claim.

When it's typically used

D7870 is reported for a TMJ arthrocentesis — inserting needles into the joint to flush/irrigate (lavage) it, minimally invasively — used for certain TMJ disorders, classically acute closed lock (limited opening from an acutely displaced disc) or joint inflammation/pain, to wash out the joint, break up minor adhesions, and improve movement and symptoms. It's the least invasive surgical TMJ procedure, often tried before arthroscopy or open surgery.

How much does D7870 cost?

An arthrocentesis is a minimally invasive procedure, less costly than open TMJ surgery or arthroscopy — the procedure itself is moderate, but the total depends on the anesthesia/sedation and setting (it's often done under sedation or general anesthesia). Coverage varies (TMJ treatment is limited or excluded by some plans). Verify your specific coverage.

Is D7870 covered by insurance?

Coverage for TMJ procedures varies — some dental and medical plans limit or exclude TMJ treatment, so coverage isn't guaranteed. Documentation of the condition (e.g., the acute closed lock/limited opening, or the joint inflammation) and the arthrocentesis supports the claim, and prior conservative care is often expected. As a relatively less invasive procedure, it's frequently used before more invasive options. Preauthorization may be required. Verifying coverage helps.

Flushing out the joint

An arthrocentesis flushes the joint with needles, and understanding this clarifies the code.

Understanding what an arthrocentesis is clarifies D7870. 'Arthrocentesis' = 'arthro-' (joint) + '-centesis' (puncture with a needle). For the TMJ, it's a procedure where needles are inserted into the joint (the upper joint space) and the joint is flushed/irrigated with fluid (lavage) — sterile fluid (like saline or lactated Ringer's solution) is run through the joint (entering through one needle and exiting through another), washing it out. So it's a needle lavage of the joint — without making a surgical incision or opening the joint.

This washing-out has several effects: it removes inflammatory mediators and debris — flushing out the inflammatory chemicals and breakdown products that accumulate in the joint fluid (which contribute to pain and inflammation); it can break up minor adhesions and free the joint — the flushing (and the hydraulic pressure/distension of the joint) can release minor adhesions and improve the joint's mobility; and it can improve the disc/condyle movement — helping a 'stuck' joint move more freely. So an arthrocentesis flushes out the joint, addressing inflammation and minor restrictions minimally invasively. Understanding this helps patients see that an arthrocentesis ('arthro-' meaning joint + '-centesis' meaning needle puncture) is a procedure where needles are inserted into the TMJ (the upper joint space) and the joint is flushed/irrigated with fluid (lavage — sterile fluid like saline run through the joint, entering one needle and exiting another, washing it out) without a surgical incision — with several effects: removing inflammatory mediators and debris (flushing out the inflammatory chemicals and breakdown products in the joint fluid that contribute to pain and inflammation), breaking up minor adhesions and freeing the joint (the flushing and hydraulic pressure/distension releasing minor adhesions and improving mobility), and improving the disc/condyle movement (helping a 'stuck' joint move more freely) — so it addresses inflammation and minor restrictions minimally invasively.

The classic use: acute closed lock

A key use is freeing a stuck jaw, and understanding this clarifies a common scenario.

A classic use of arthrocentesis is treating an acute closed lock — and understanding it clarifies a common scenario for D7870. A 'closed lock' refers to a situation where the TMJ disc is displaced and doesn't reduce (the disc is stuck in front of the condyle and doesn't return to position when the jaw opens) — this blocks the condyle's normal movement, so the jaw can't open fully (limited opening, the jaw feeling 'stuck' or locked closed/partially). This is an acute disc displacement without reduction.

An arthrocentesis can address this: the lavage (flushing the joint), often combined with distending the joint (the hydraulic pressure) and manipulating the jaw, can release the restriction — freeing up the disc/condyle movement, breaking minor adhesions, and improving the jaw's opening. It often improves the limited opening and pain, and it's minimally invasive — so it's frequently used for an acute closed lock (especially when conservative measures haven't resolved it), often before considering more invasive surgery. So arthrocentesis is a key treatment for a stuck/locked jaw (acute closed lock). Understanding this helps patients see that a classic use of arthrocentesis is treating an acute closed lock — a situation where the TMJ disc is displaced and doesn't reduce (stuck in front of the condyle, not returning to position when the jaw opens), blocking the condyle's normal movement so the jaw can't open fully (limited opening, feeling 'stuck' or locked) — an acute disc displacement without reduction — which an arthrocentesis can address: the lavage (flushing the joint), often combined with distending the joint (hydraulic pressure) and manipulating the jaw, can release the restriction (freeing the disc/condyle movement, breaking minor adhesions, improving the opening), often improving the limited opening and pain minimally invasively, so it's frequently used for an acute closed lock (especially when conservative measures haven't resolved it), often before more invasive surgery.

The technique and added medications

The lavage may include an injected medication, and understanding this clarifies the procedure.

Understanding the technique clarifies what's involved in D7870. The arthrocentesis is typically done as follows: anesthesia — often under sedation or general anesthesia (sometimes local anesthesia with sedation), as it involves needle placement and joint distension; needle placement — one or two needles are inserted into the upper joint space (identified by anatomical landmarks); lavage — fluid is flushed through the joint (irrigating it), washing out the inflammatory mediators and debris; distension/manipulation — the joint may be distended with fluid (hydraulic pressure to free adhesions) and the jaw manipulated to improve mobility; and an optional injected medication — at the end, a medication may be injected into the joint, such as a corticosteroid (to reduce inflammation) or hyaluronic acid/sodium hyaluronate (a lubricating/viscosupplementation agent) — as an addition to the lavage.

The whole procedure is relatively quick and minimally invasive (needles, no incision). Afterward, the patient may have some improvement in opening and pain, with aftercare (e.g., a soft diet, jaw exercises) as advised. So the technique is a needle lavage, sometimes with an injected medication. Understanding this helps patients see that the arthrocentesis is typically done under sedation or general anesthesia (sometimes local with sedation), inserting one or two needles into the upper joint space (by anatomical landmarks), flushing fluid through the joint (lavage, washing out inflammatory mediators and debris), often distending the joint (hydraulic pressure to free adhesions) and manipulating the jaw to improve mobility, and optionally injecting a medication at the end (such as a corticosteroid to reduce inflammation or hyaluronic acid as a lubricating agent, as an addition to the lavage) — the whole procedure being relatively quick and minimally invasive (needles, no incision), with the patient possibly having improvement in opening and pain afterward and aftercare (a soft diet, jaw exercises) as advised.

The least invasive surgical TMJ procedure

Arthrocentesis is the least invasive joint procedure, and understanding this clarifies the coding.

Understanding where arthrocentesis sits among the TMJ procedures clarifies the coding. The surgical TMJ procedures (in the D7810-D7899 group) range in invasiveness, and arthrocentesis (D7870) is at the least invasive end: arthrocentesis (D7870, this code) — needles to flush the joint, no incision/no scope — the least invasive; arthroscopy (D7872-D7877) — a small scope through tiny punctures (minimally invasive, allowing some surgical procedures with visualization); and arthrotomy/open surgery (D7860 and the open procedures D7840/D7850/D7852/D7854/D7865/D7858) — open joint surgery (the most invasive). So the progression is arthrocentesis < arthroscopy < open surgery.

Because it's the least invasive (and relatively simple), arthrocentesis is often tried earlier — for suitable conditions (like an acute closed lock or joint inflammation), it may be done before escalating to arthroscopy or open surgery (which are reserved for cases that need more). So D7870 (arthrocentesis) is the least invasive surgical TMJ procedure — a first-line joint intervention for appropriate cases. The surgeon codes D7870 for a joint lavage via needles (vs the arthroscopy or open codes for more invasive approaches). Understanding this helps patients see that the surgical TMJ procedures (in the D7810-D7899 group) range in invasiveness, with arthrocentesis (D7870, this code) at the least invasive end — arthrocentesis (needles to flush the joint, no incision or scope, the least invasive), arthroscopy (D7872-D7877, a small scope through tiny punctures, minimally invasive, allowing some surgical procedures with visualization), and arthrotomy/open surgery (D7860 and the open procedures, the most invasive) — so the progression is arthrocentesis < arthroscopy < open surgery, and because it's the least invasive and relatively simple, arthrocentesis is often tried earlier (for suitable conditions like an acute closed lock or joint inflammation, before escalating to arthroscopy or open surgery, which are reserved for cases that need more), so D7870 is the least invasive surgical TMJ procedure (a first-line joint intervention for appropriate cases), coded for a needle lavage versus the arthroscopy or open codes.

Frequently asked questions

What is the D7870 dental code?

It's an arthrocentesis of the temporomandibular joint (TMJ) — a minimally invasive procedure where needles are inserted into the joint to flush (lavage) and irrigate it with fluid, without open surgery. It's used for certain TMJ disorders (like an acute closed lock or joint inflammation) to wash out the joint, break up minor adhesions, and improve jaw movement and symptoms.

What does 'arthrocentesis' mean?

'Arthro-' means joint and '-centesis' means puncture with a needle — so an arthrocentesis is the needle puncture of a joint, here to flush/irrigate (lavage) it. Needles are inserted into the joint and fluid is run through to wash it out, without a surgical incision. It's the least invasive of the surgical TMJ procedures.

What is a 'closed lock,' and how does this help?

A closed lock is when the TMJ disc is displaced and doesn't reduce — stuck in front of the condyle, blocking normal movement so the jaw can't open fully (it feels 'stuck'). An arthrocentesis (flushing the joint, with distension and manipulation) can release the restriction, free the disc/condyle movement, break minor adhesions, and improve the opening and pain.

How does flushing the joint reduce pain?

The lavage washes out inflammatory mediators and debris that accumulate in the joint fluid (which contribute to pain and inflammation), and it can break up minor adhesions and improve the joint's movement. A medication (like a corticosteroid or hyaluronic acid) may also be injected at the end to further reduce inflammation or lubricate the joint.

How is it different from arthroscopy or open surgery?

Arthrocentesis (D7870) is the least invasive — just needles to flush the joint, no incision or scope. Arthroscopy (D7872-D7877) uses a small scope through tiny punctures (minimally invasive). Open surgery (arthrotomy and the open procedures) surgically opens the joint (most invasive). Arthrocentesis is often tried earlier, before escalating to those.

What does it cost, and what insurance applies?

It's minimally invasive and less costly than open TMJ surgery or arthroscopy, though the total depends on the anesthesia/sedation and setting (it's often done under sedation or general anesthesia). Coverage for TMJ procedures varies (some plans limit or exclude TMJ treatment). Verify your specific coverage.

This page is an independent, plain-language explanation for general information only. It is not billing, coding, or clinical advice. For the official CDT descriptor and current-year wording, refer to the American Dental Association.