When to Choose Vertical Over Horizontal Bitewings

The choice between vertical vs. horizontal bitewings comes down to one question: what do you need to see? Horizontal bitewings handle most caries checks well. Once bone levels drop, though, the crest can slip off the edge of the image. That's where vertical bitewings earn their place, and the 2026 ADA guidance now says so directly.

TL;DR

• Use horizontal bitewings for caries checks when bone levels are close to normal.

• Switch to vertical bitewings once bone loss pushes the crest out of a horizontal view.

• Follow the 2026 ADA–AAOMR guidance, which recommends vertical bitewings for periodontal patients.

• Base every image on clinical findings, not on a fixed schedule or insurance frequency.

What Are Horizontal and Vertical Bitewing X-Rays?

A bitewing captures the crowns of upper and lower posterior teeth on one image while the patient bites on a tab or holder. The bitewing X-ray glossary entry covers the basics. The only thing that changes between the two types is which way the receptor is turned, and that decides how much of the tooth and bone ends up in the picture. For broader context on intraoral imaging, see what radiographic imaging is.

Horizontal Bitewing Radiographs

In a horizontal bitewing, the long side of the receptor runs front to back. That gives a wide view of several teeth, with good coverage of the crowns, the contact points, and the bone just below the cementoenamel junction.

This is the workhorse view for finding interproximal caries, checking the margins of fillings and crowns, and spotting calculus. It also shows the crestal bone, as long as the crest sits close to where it should. In a healthy adult, that's usually not a problem.

Vertical Bitewing Radiographs

Turn the same receptor 90 degrees, and you get a vertical bitewing. The image is narrower front to back but taller top to bottom, so it reaches further down the roots of both arches.

That extra height is the whole point. When a patient has lost bone, the crest may sit several millimeters further down the root. A vertical bitewing can still capture it, along with molar furcations and more of the exposed root surface. The receptor still has to be centered properly, though. A vertical bitewing that cuts off the bone you were trying to see is no better than a horizontal one.

Vertical vs. Horizontal Bitewings: Key Differences

Both views show the same teeth, just framed differently. The trade-off is width for height. Here's how they compare in practice:

One point of language trips people up. A vertical bitewing is a way of taking the image. Vertical bone loss is a pattern of disease, where bone is lost at an angle next to one tooth. Horizontal bone loss is the even, level kind. Either type of bone loss can show up on either type of bitewing. A patient with plain horizontal bone loss may still need vertical bitewings if that loss is deep enough.

When Should Professionals Use Horizontal Bitewings?

For most patients with healthy gums, horizontal bitewings are the right call. If probing depths are normal and there's no sign of bone loss, the crest will sit comfortably inside the image. A horizontal view also covers more teeth per exposure, so fewer images may be needed.

They're the standard for checking contacts you can't see directly. Interproximal caries in premolars and molars often hide until they're well into dentin, and a well-angled horizontal bitewing is still one of the best ways to catch them early. The same image shows overhangs, open margins, and recurrent decay around old fillings.

The bigger question is often whether to take bitewings at all. The ADA–AAOMR recommendations are clear that imaging should follow the history, the exam, and a risk assessment. A low-risk adult with recent clean bitewings may not need new ones at this recall. A patient with several new lesions probably does. Children, teens, and adults each have different intervals, and those intervals stretch or shrink with caries risk.

What shouldn't drive the decision is a fixed calendar or an insurance benefit that resets every year. If the last set is recent and nothing has changed clinically, the most useful image may be the one already on file.

When Are Vertical Bitewings the Better Choice?

The short answer: when the bone has moved. Once periodontal disease has pulled the crest down the root, a horizontal image often shows healthy-looking crowns and very little of what matters. The 2026 ADA–AAOMR recommendations now back vertical bitewings for exactly this situation.

Patients With Periodontal Bone Loss

The guidance recommends vertical bitewings to assess bone levels in patients with a history of, or active, periodontal disease. That applies to adolescents with periodontal disease in the permanent dentition too. For a full periodontal workup, it recommends a full-mouth series with vertical bitewings added as needed.

The reason is simple. If the crest has dropped below the edge of the image, nobody can measure it. A 2020 review of 320 patient records found the bone loss level visible on about 53% of vertical images, compared with under 4% of horizontal ones. That's a coverage problem, not a resolution one. Bone levels also feed directly into periodontitis staging and grading, so an image that misses them can change the diagnosis.

There's a bonus for caries too. Perio patients often have recession and exposed roots, which are prone to root caries. A vertical view captures more of those root surfaces.

Assessing Furcation Involvement

Molar furcations sit lower than the crestal bone, so they're often the first thing a horizontal image crops out. In a 2023 crossover study of 20 patients, vertical bitewings showed the furcation area in every molar, compared with 57.5% on horizontal images. The sample was small, so the exact numbers shouldn't be stretched too far. The pattern fits what most clinicians see, though.

Periodontal Baseline and Follow-Up Imaging

Vertical bitewings make a good baseline before periodontal therapy and a useful way to track changes afterward. For comparisons to mean anything, the technique has to match each time. A slightly different vertical angle can make bone look higher or lower than it really is. Using the same holder and aiming ring helps keep projections consistent.

Radiographs still only support the clinical exam. Probing depths, attachment loss, bleeding, and mobility tell you what's happening now. The image shows how much bone is left, and only in two dimensions.

How to Position Horizontal and Vertical Bitewing Radiographs

The basics are the same for both. Center the receptor on the contacts you care about, have the patient close evenly, and aim the beam straight through the contacts so they open up. A good bitewing shows open contacts, both arches, and the crestal bone. The premolar view should reach the distal of the canine. Proper training matters here, and the dental X-ray certification guide covers state requirements.

Vertical bitewings ask a bit more of the patient. The receptor sits taller in the mouth, so it pushes into the palate above and the floor of the mouth below. Rigid digital sensors make that harder. The 2026 guidance itself acknowledges they can be technically difficult with sensors.

Common Horizontal Bitewing Errors

The usual problems are overlapped contacts from a poor horizontal angle, cone cuts, and a missing distal surface on the last molar. The one that matters most for perio is a crest that's simply out of frame. If you can't see bone below the contacts, a retake as a horizontal won't fix it.

Common Vertical Bitewing Errors

With vertical images, the receptor often sits too low or too high. That can cut off the occlusal surfaces or miss the bone it was meant to capture. Sensors also slip when patients gag or can't close fully. Overlapping contacts are still possible, and the narrower width leaves less room for error.

How to Reduce Repeat Exposures

Retakes are where radiation adds up. In the 2023 study, it took an average of 5.9 exposures to get four good vertical bitewings, against 5.3 for horizontals. Small differences like that add up across a busy schedule.

A few habits help. Use holders with aiming rings, especially for vertical views. Pick the receptor size that fits the patient's mouth, and consider a smaller sensor or phosphor plate for a shallow palate. Check existing images before taking new ones. And if you already know the patient has bone loss, start with verticals instead of taking horizontals first and retaking.

Diagnostic Evidence, Radiation Exposure, and Limitations

The research on this topic is thinner than you might expect, but it points the same way. Vertical bitewings show more of what matters once bone is lost. One detail is easy to miss. In the 2023 study, the distance from the cementoenamel junction to the crest measured about the same on both views when the crest was visible. So vertical bitewings don't measure bone more precisely. They just keep it in the frame.

Radiation doesn't depend on orientation. A single vertical bitewing and a single horizontal one deliver about the same dose with the same settings. What changes the total is the number of exposures, the receptor type, the exposure settings, and collimation. Rectangular collimation cuts dose noticeably for any intraoral image. A vertical series may need an extra image or two to cover the same teeth, so it's worth planning the set before starting.

Every bitewing shares the limits of a 2D image. The buccal and lingual bone plates overlap, so a crater between teeth or a defect on one side can be hidden. Bone loss is usually a little worse than it looks on film. Early changes may not show at all until enough mineral is gone. That's one reason software that measures bone on radiographs, covered in the AI periodontal disease detection article, still depends on getting the crest in the image first.

Clinical Scenarios: Which Bitewing Orientation Should You Choose?

The probe usually makes the decision before the X-ray unit does. Pocket depths, attachment loss, and existing images tell you whether the crest is likely to fit in a horizontal view. These examples show how that plays out:

These aren't automatic orders. A patient in periodontal maintenance with stable pockets may not need new images at every visit. A patient with healthy gums but heavy restorations may still need an extra view.

Whatever is taken should be read alongside the charting and recorded in the dental treatment plan. The guide on how to prepare a dental treatment plan covers how imaging fits into that process.

Bottom Line

Horizontal bitewings are still the right default for most caries checks in patients with healthy bone levels. Once periodontal disease has lowered the crest, vertical bitewings become the better tool, and the 2026 ADA–AAOMR recommendations say so plainly. Vertical views don't measure bone more accurately. They simply keep it in the picture, along with furcations and exposed roots. Let the probing chart guide the choice, plan the series before you start, and check what's already on file before adding another exposure.