Why a Facebow Is Essential for Restorative Success

When do I need a facebow? The short answer: most of the time, you don’t.

Many excellent single-tooth restorations can be successfully fabricated using quadrant impressions and a hinge-type articulator, with no facebow record required. The need for anything else utterly confounded me after graduating from dental school. In fact, I sold my fully adjustable articulator, facebow included, for $150 right after I left, and later regretted that decision once I understood what the instrument actually does.

What is a facebow, and why does it matter?

There are two kinds of facebows: kinematic and arbitrary. A kinematic version locates the terminal hinge axis of condylar rotation. An arbitrary version, often called an earbow, uses the ear canal as a locating point instead.

Pantographs are kinematic devices that also record condylar movement, allowing them to be programmed into a fully adjustable articulator. They’re precise, but complex and challenging to master. The arbitrary style trades some accuracy for simplicity, and the literature is divided on how much that accuracy matters in daily practice (Farias-Neto, Dias, de Miranda, & de Oliveira, 2013).

At Spear, we use the earbow because there’s no need to complicate dentistry any further than it already is. We use a semi-adjustable articulator rather than a fully adjustable instrument for the same reason.

The articulator’s job is to relate the upper and lower models to each other once the casts are mounted in a seated condylar position. The facebow’s job is to orient the upper model in three dimensions relative to the condyle’s rotational axis. Together, they let you move the mounted casts in a way that mimics how the condyle actually moves in the fossa.

That distinction matters even for single-unit dentistry. If the goal is to reproduce accurate jaw movement, then an accurate starting position for the condyle is essential. One of the movements the record helps recreate is the arc of opening and closing.

A hinge articulator changes the position of the condyles relative to the upper arch, which changes the mandible’s entire opening and closing arc. The result can be restorations that need real adjustment to fit the patient’s bite, in opening and closing, and in excursive movements alike.

How does a facebow help in everyday cases?

Beyond condylar mechanics, this five-minute step earns its place across three situations you’ll recognize from daily practice.

Esthetic cases: A facebow places the maxillary cast in its true orientation, so you and your lab technician can see a cant, an unusually steep maxillary angle, or a shift in incisal edge position before you commit to a wax-up.

Wear cases: Locating the maxilla relative to the hinge axis matters when you’re transferring a pattern of pathologic wear to the lab, or planning a single crown on a second molar affected by retrusive, centric relation wear.

Any restorative case: Mount models from a handful of patients and you’ll see how inconsistently the maxilla actually sits relative to the skull: anterior, posterior, tilted, or slanted. A hinge articulator assumes every patient is the same. A facebow confirms whether that assumption holds for the one in your chair.

Capturing the record takes less than five minutes, and it can save considerable chairside time, and even a remake, when you’re restoring the last teeth in an arch or several teeth at once.

A quick technique note: mark the anterior reference point 43 mm from the incisal edge of tooth #7 or #8, on the patient’s right side of the face. Slide-type facebows work with most major articulator systems, including Denar, SAM, and Whip Mix, as well as with KaVo systems using a transfer jig. Getting that landmark-and-equipment pairing right the first time is what keeps the record accurate and repeatable.

This same record also orients the upper cast to the horizon, which matters most when you’re restoring anterior teeth and need the incisal edges placed correctly. With an accurately recorded facebow, you and your lab technician can assess any cant or occlusal plane irregularity relative to the horizontal plane.

What about a stick bite instead of a facebow?

Some clinicians who stopped using a facebow after dental school rely on a stick bite or place models in the articulator by hand, on the assumption that it only provides mounting convenience.

That assumption is the gap worth closing. The record does more than position a cast in space. It transfers the patient’s actual condylar and occlusal plane relationships to the articulator, information that a stick bite or hand placement can’t fully replicate. Skipping that step is often what shows up later as excessive chairside adjustment when the restoration or provisional goes back into the mouth.

Is a facebow worth the extra step?

The concepts behind a facebow can seem complex on paper, but the practice is simple: a few extra minutes chairside, and a record that lets your lab technician mount your case the way your patient’s jaw actually moves.

Used with a semi-adjustable articulator, a facebow record ultimately saves time, reduces remakes, and helps you deliver restorations that need less adjustment at delivery.

Contributing Authors
Dr. Dave St. Ledger & Dr. Greggory Kinzer