What D7840 means

D7840 covers a condylectomy. "D" is dental, "78" is this oral surgery (TMJ) group, and "40" is this condylectomy. 'Condyle' refers to the mandibular condyle — the rounded projection at the top of the back of the lower jaw (mandible) that fits into the socket of the skull to form the temporomandibular joint (TMJ); '-ectomy' means surgical removal. So a condylectomy is the surgical removal of the mandibular condyle (or a portion of it). It's a TMJ surgery.

So it's surgically removing the condyle (the top of the lower jaw that forms the jaw joint), or part of it — done for conditions affecting the condyle.

A condylectomy is performed for various conditions affecting the condyle, such as: a tumor or growth — a benign or malignant tumor of the condyle (removing the affected bone); condylar hyperplasia — an overgrowth/enlargement of one condyle causing facial asymmetry and a deviated jaw/bite (removing or reshaping the overgrown condyle — sometimes a 'high condylectomy' removing the top portion to halt the overgrowth and correct the asymmetry); severe degenerative or destructive joint disease — advanced arthritis/degeneration or other destructive conditions damaging the condyle; ankylosis — (the joint fused) where the condyle may be removed as part of releasing it; and other condylar pathology. Depending on how much is removed and why, the joint may be reconstructed (a separate consideration — e.g., joint reconstruction, D7858), or the procedure may reshape the condyle. It's a significant surgery performed by an oral and maxillofacial surgeon, under general anesthesia, with surgical access to the joint. This code is in the TMJ group (D7810-D7899). TMJ-related coverage varies (and a tumor would generally be a medical matter). Documentation of the condition and the procedure supports the claim.

When it's typically used

D7840 is reported for a condylectomy — surgically removing the mandibular condyle (or a portion) — done for conditions affecting the condyle, such as a tumor/growth, condylar hyperplasia (overgrowth causing asymmetry), severe degenerative/destructive joint disease, ankylosis, or other condylar pathology. It may be combined with or followed by joint reconstruction depending on the situation.

How much does D7840 cost?

A condylectomy is a significant TMJ surgery — some fee schedules list an allowance around 1,000 USD for the surgical code, but the total (with hospital/facility, general anesthesia, and any reconstruction) is considerably higher. If done for a tumor or with reconstruction, the overall cost is greater. Coverage varies (a tumor is generally medical; TMJ degenerative conditions may face TMJ-coverage limits). Verify your specific coverage.

Is D7840 covered by insurance?

Coverage depends on the indication — a tumor/growth is generally a medical matter (medical insurance), while TMJ degenerative/dysfunction indications may face TMJ-coverage limitations in some dental/medical plans. Documentation of the condition (the condylar pathology — e.g., tumor, hyperplasia, severe degeneration) and the condylectomy supports the claim. It's a significant surgery usually requiring preauthorization. Any reconstruction (D7858) is separate. Verifying coverage helps.

The condyle and what a condylectomy removes

A condylectomy removes the condyle (part of the jaw joint), and understanding this clarifies the code.

Understanding the condyle clarifies D7840. The mandibular condyle is the rounded knob at the top of the back of the lower jaw (mandible) — it's the part of the lower jaw that fits into a socket (the glenoid fossa) in the skull's temporal bone, forming the temporomandibular joint (TMJ). The condyle is covered with cartilage and moves within the joint (rotating and sliding) as the jaw opens, closes, and moves. So the condyle is a key part of the jaw joint.

A condylectomy is the surgical removal of this condyle — either the whole condyle or a portion of it (e.g., a 'high condylectomy' removing just the top part). Because the condyle is part of the TMJ, removing it (or part of it) alters the joint — so a condylectomy is done for specific conditions where the condyle is diseased, deformed, or problematic, and removing it is beneficial. Depending on how much is removed, the joint's function is affected, and reconstruction may be considered to restore it. So a condylectomy removes the condyle (part of the jaw joint). Understanding this helps patients see that the mandibular condyle is the rounded knob at the top of the back of the lower jaw that fits into a socket in the skull to form the temporomandibular joint (TMJ) — covered with cartilage and moving within the joint as the jaw opens, closes, and moves — so a condylectomy is the surgical removal of this condyle (the whole condyle or a portion, e.g., a 'high condylectomy' removing the top part), which alters the joint (since the condyle is part of the TMJ), done for specific conditions where the condyle is diseased, deformed, or problematic, with reconstruction sometimes considered depending on how much is removed.

Conditions treated by condylectomy

Several conditions can require a condylectomy, and understanding them clarifies the indications.

A condylectomy (D7840) is done for various conditions affecting the condyle — and understanding them clarifies the indications: a tumor or growth — a benign or malignant tumor of the condyle (or involving it) is removed by removing the affected bone (the condyle); condylar hyperplasia — an overgrowth/enlargement of one condyle (it keeps growing abnormally), which causes the lower jaw to grow asymmetrically — leading to facial asymmetry, a deviated chin/jaw, and a canted (tilted) bite; a condylectomy (often a 'high condylectomy,' removing the top growing portion) halts the overgrowth and helps correct the asymmetry; severe degenerative/destructive joint disease — advanced arthritis or other destructive processes severely damaging the condyle, where removing the damaged condyle is part of treatment; ankylosis — where the joint has fused (the condyle fused to the skull base, locking the jaw); removing the fused condyle/bony mass is part of releasing the ankylosis to restore movement; and other condylar pathology — e.g., certain fractures' sequelae, or other lesions.

So the condylectomy addresses a diseased, overgrown, deformed, or fused condyle. The specific condition determines the goal (removing a tumor, correcting asymmetry, releasing ankylosis, etc.) and whether reconstruction follows. Understanding this helps patients see that a condylectomy (D7840) is done for various conditions affecting the condyle — a tumor or growth (benign or malignant, removed with the affected bone), condylar hyperplasia (one condyle overgrowing, causing facial asymmetry, a deviated jaw, and a canted bite — often treated by a 'high condylectomy' removing the top growing portion to halt the overgrowth and correct the asymmetry), severe degenerative/destructive joint disease (advanced arthritis or other processes severely damaging the condyle), ankylosis (the joint fused, with the condyle/bony mass removed to release it and restore movement), and other condylar pathology — so the procedure addresses a diseased, overgrown, deformed, or fused condyle, with the specific condition determining the goal and whether reconstruction follows.

The surgery and joint reconstruction

A condylectomy may be paired with reconstruction, and understanding this clarifies the broader treatment.

Understanding the surgery and the question of reconstruction clarifies the broader treatment. A condylectomy is a significant TMJ surgery: surgical access — the surgeon accesses the joint (typically through an incision in front of the ear — a preauricular approach — or another approach), exposing the condyle; removal — removing the condyle (or the portion indicated) — e.g., the whole condyle for a tumor, or the top portion for a hyperplasia; and managing the joint — addressing what remains and the joint space. Because removing the condyle removes part of the joint, a key question is reconstruction: whether and how to restore the joint/the jaw's support.

Reconstruction options (separate considerations/codes, like joint reconstruction D7858) depend on the situation: in some cases (e.g., a high condylectomy for hyperplasia, removing only the top), the remaining condyle/joint may function, possibly with the disc repositioned; in cases where the whole condyle is removed (e.g., a tumor), the joint may be reconstructed — using a graft (e.g., a costochondral rib graft to recreate a condyle) or a prosthetic joint (a total joint replacement) — to restore the jaw's support and function. So the treatment may be the condylectomy alone or with reconstruction. The surgeon plans this based on the condition and how much is removed. Understanding this helps patients see that a condylectomy is a significant TMJ surgery — accessing the joint (e.g., through a preauricular incision in front of the ear), removing the condyle (or the indicated portion), and managing the joint — and because removing the condyle removes part of the joint, a key question is reconstruction (whether and how to restore the joint/jaw support): in some cases (e.g., a high condylectomy for hyperplasia) the remaining joint may function, while in cases where the whole condyle is removed (e.g., a tumor) the joint may be reconstructed with a graft (e.g., a costochondral rib graft) or a prosthetic joint (total joint replacement) — a separate consideration/code (like joint reconstruction, D7858) — so the treatment may be the condylectomy alone or with reconstruction, planned by the surgeon based on the condition and how much is removed.

Where D7840 fits in the codes

D7840 is one of the TMJ surgical codes, and understanding this clarifies the coding.

D7840 is one of the TMJ (temporomandibular joint) surgical codes — and understanding this clarifies the coding. The TMJ group (D7810-D7899) progresses from dislocation reduction (D7810/D7820) and manipulation under anesthesia (D7830) into the surgical procedures on the joint, which address different structures/aspects: bone — condylectomy (D7840, this code — removing the condyle); the disc — surgical discectomy (D7850, removing the disc), disc repair (D7852); the synovium — synovectomy (D7854); muscle — myotomy (D7856); reconstruction — joint reconstruction (D7858); and joint-access/procedures — arthrotomy (D7860, opening the joint), arthroplasty (D7865, reshaping the joint), arthrocentesis (D7870), lysis/lavage (D7871), and arthroscopy (D7872-D7877).

D7840 specifically is the condylectomy — the surgical removal of the condyle (the bone component of the joint). The surgeon codes it when the condyle (or a portion) is surgically removed for a condylar condition. It's distinguished from the disc procedures (D7850/D7852), the soft tissue procedures (D7854/D7856), and the joint-access/reshaping procedures — D7840 targets the condyle itself. So D7840 is the condylectomy in the TMJ surgical group. Understanding this helps patients see that D7840 is one of the TMJ surgical codes (in the D7810-D7899 group, which progresses from dislocation reduction and manipulation under anesthesia into surgical procedures on the joint's different structures) — addressing bone (condylectomy D7840, this code), the disc (discectomy D7850, disc repair D7852), the synovium (synovectomy D7854), muscle (myotomy D7856), reconstruction (D7858), and joint-access/procedures (arthrotomy D7860, arthroplasty D7865, arthrocentesis D7870, and others) — so D7840 specifically is the condylectomy (removing the condyle, the bone component), coded when the condyle is surgically removed for a condylar condition, distinguished from the disc, soft tissue, and joint-access procedures by targeting the condyle itself.

Frequently asked questions

What is the D7840 dental code?

It's a condylectomy — the surgical removal of the mandibular condyle (the rounded top of the lower jaw that forms part of the jaw joint, the TMJ), or a portion of it. It's a TMJ surgery done for conditions affecting the condyle, such as a tumor, condylar overgrowth (hyperplasia), severe joint degeneration, ankylosis, or other condylar pathology.

What is the condyle?

The mandibular condyle is the rounded knob at the top of the back of the lower jaw (mandible) that fits into a socket in the skull to form the temporomandibular joint (TMJ). It's covered with cartilage and moves within the joint as the jaw opens, closes, and moves. A condylectomy removes this condyle (or part of it).

Why would someone need a condylectomy?

For conditions affecting the condyle — a tumor or growth (removing the affected bone), condylar hyperplasia (one condyle overgrowing, causing facial asymmetry and a tilted bite — often treated by removing the top growing portion), severe degenerative/destructive joint disease, ankylosis (a fused joint, releasing it), or other condylar pathology.

What is condylar hyperplasia?

An abnormal overgrowth/enlargement of one condyle, which makes the lower jaw grow asymmetrically — causing facial asymmetry, a deviated chin/jaw, and a canted (tilted) bite. A condylectomy (often a 'high condylectomy,' removing the top growing portion) can halt the overgrowth and help correct the asymmetry.

Is the joint reconstructed afterward?

It depends. In some cases (e.g., a high condylectomy removing only the top), the remaining joint may function. When the whole condyle is removed (e.g., for a tumor), the joint may be reconstructed — using a graft (like a costochondral rib graft) or a prosthetic total joint — to restore the jaw's support and function. Reconstruction is a separate consideration (e.g., D7858).

What does it cost, and what insurance applies?

It's a significant TMJ surgery — some fee schedules list around 1,000 USD for the surgical code, but the total (with hospital/facility, general anesthesia, and any reconstruction) is considerably higher. Coverage depends on the indication (a tumor is generally medical; TMJ conditions may face TMJ-coverage limits). 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.