A Practical, Step-by-Step Guide to Increasing Vertical Dimension of Occlusion

Introduction

Vertical dimension remains one of the most debated—and often avoided—topics in comprehensive dental rehabilitation. Ask ten clinicians when, why, or how to alter the vertical dimension of occlusion (VDO), and you’re likely to hear ten different answers. Some believe it should only be changed in extreme cases, while others argue it cannot be predictably altered at all.

This lack of consensus has left many dentists hesitant to address VDO, despite the fact that worn dentitions are commonplace in everyday general practice. The result? Patients who struggle with compromised function, aesthetics, or both.

A quick search for “Vertical Dimension of Occlusion in Dentistry” yields tens of thousands of publications. Narrowing that search to recent decades still produces an overwhelming volume of information—much of it focused on muscles of mastication, TMJ position, mandibular posture, centric relation, occlusal space, anterior guidance, and facial aesthetics. All of these variables matter, but without a clear framework, the topic can feel unnecessarily complex.

The goal of this article is to simplify the process and present a structured, repeatable method for increasing vertical dimension in a predictable and aesthetic way.

Rethinking VDO as an Aesthetic Parameter

According to The Glossary of Prosthodontic Terms, vertical dimension of occlusion is defined as “the lower facial height measured between two points when the occluding members are in contact.” In practical terms, it describes the vertical relationship between the maxilla and mandible when the teeth are fully intercuspated.

While many clinicians associate VDO changes exclusively with full-mouth reconstructions, the same principles apply whether treating an edentulous patient with dentures or restoring a dentate patient with fixed restorations. In both scenarios, treatment planning begins in the same place: the position of the maxillary central incisors.

For this reason, it is often more useful to think of VDO as the Vertical Dimension of Aesthetics. The final position of the anterior teeth dictates not only facial harmony, but also phonetics, smile display, and occlusal function.

When evaluating patients with worn or shortened dentitions, incisor position should be assessed both at full smile and at rest. A simple and reliable way to capture the rest position is to have the patient say the word “Emma” and relax. Traditionally, central incisor display at rest has been cited as 2–4 mm, but studies have shown a much broader range in adults.

Research has demonstrated that canine position is often a more consistent landmark. When the canine sits just behind the upper lip at rest (±1 mm), the resulting central incisor position tends to be more accurate for aesthetic planning, as the canine and central incisors exist on the same aesthetic plane.

Step 1: Record Existing Tooth Measurements

The first step in evaluating a patient for a vertical dimension change is documenting their current anterior tooth relationships. These measurements serve as the baseline for both treatment planning and laboratory communication.

Four key measurements should be recorded:

• Length of the maxillary central incisor

• Length of the opposing mandibular central incisor

• CEJ-to-CEJ distance between those two teeth

• Existing overbite

The CEJ-to-CEJ measurement is calculated by adding the maxillary and mandibular incisor lengths and subtracting the overbite. For example, if both incisors measure 7 mm and the overbite is 3 mm, the CEJ-to-CEJ dimension is 11 mm. These numbers will later be compared to the planned final dimensions to determine the required increase in VDO.

Step 2: Determine the New Maxillary Central Incisor Length

Most unworn maxillary central incisors measure between 10 and 12 mm. When a patient presents with significantly shortened incisors, restorative length must often be added to reestablish proper aesthetics.

A practical way to visualize the ideal incisal edge position is by adding flowable composite to the central and canine incisors chairside. This allows the clinician to confirm smile display, lip support, and phonetics before committing to a final length. In many cases, a target length of approximately 10 mm provides an excellent starting point.

If crown lengthening is planned, the amount of anticipated tissue reduction should be added to the final incisor length when determining the overall restorative target.

Step 3: Select the Mandibular Central Incisor Length

Mandibular central incisors are typically shorter than their maxillary counterparts, with an average length of approximately 8 mm in unworn dentitions.

When increasing the length of lower incisors, it is important to ensure that the added length does not create excessive mandibular tooth display at rest or during speech. Chairside mock-ups with flowable composite can be especially helpful in evaluating this visually before finalizing the treatment plan.

Why Overbite Matters: Anterior Guidance Explained

Anterior guidance plays a critical role in protecting the posterior dentition. It is defined as the relationship of the anterior teeth that disengages posterior teeth during all eccentric mandibular movements.

When posterior teeth remain in contact during excursions, elevator muscle activity increases significantly. In contrast, when only anterior teeth are engaged, muscle activity decreases. This is the foundation of a mutually protected occlusion, where anterior teeth guide movement and posterior teeth are protected from excessive lateral forces.

Canine-guided and anterior-guided occlusal schemes have long been recognized as effective ways to manage parafunctional forces. Unlike removable night guards, anterior guidance is built into the dentition and does not rely on patient compliance.

Overbite directly influences anterior guidance. Excessive overbite can prolong anterior contact during function and increase the risk of interferences within the envelope of function. Reducing overbite when increasing VDO helps minimize these risks and promotes smoother, more protective occlusal movement.

Step 4: Establish the New CEJ-to-CEJ Dimension

Once the desired maxillary and mandibular incisor lengths have been selected, the next step is determining the ideal overbite.

For example:

• Maxillary central incisor: 10 mm

• Mandibular central incisor: 8 mm

• Desired overbite: 3 mm

This results in a new CEJ-to-CEJ measurement of 15 mm. If the patient’s original CEJ-to-CEJ measurement was 11 mm, the vertical dimension must be increased by 4 mm to achieve the planned outcome.

This calculation removes guesswork and provides a clear, measurable rationale for altering the vertical dimension.

Step 5: Recording the Bite at the New Vertical Dimension

To ensure predictable occlusion, the bite record should be taken in centric relation at the exact increased vertical dimension. Simply asking the laboratory to open the articulator without precise records can compromise horizontal accuracy and lead to significant occlusal adjustments later.

A leaf gauge is an effective tool for establishing the desired vertical opening. It can be adjusted incrementally and verified using a gauge to confirm the new CEJ-to-CEJ measurement. Alternatively, composite stops placed on the lower incisors can serve as a fixed anterior stop.

Once the anterior position is stabilized, the posterior space should be recorded using a rigid bite registration material with sufficient hardness to prevent distortion. After the posterior record sets, the anterior segment is recorded separately. This method can be used for both traditional and digital workflows, allowing the lab to accurately design the case at the intended vertical dimension.

Provisionalization: The True Test of VDO

After the diagnostic wax-up is completed, provisional restorations are used to test aesthetics, phonetics, comfort, and occlusal function in real time. Evaluating lateral and protrusive movements in provisionals provides invaluable information before moving to definitive restorations.

Compared to removable appliances, provisionals offer a far more reliable assessment of vertical dimension changes. While patients may tolerate large increases in VDO with removable devices, excessive tooth length can create functional and aesthetic challenges that only become apparent once fixed restorations are in place.

Starting with the end result in mind—and validating it through provisionals—allows clinicians to move forward with confidence.

Conclusion

Increasing vertical dimension does not have to be intimidating. By approaching the process systematically—beginning with incisor position, using measurable reference points, and validating changes through provisionals—clinicians can achieve predictable, aesthetic, and functional outcomes.

Once the new vertical dimension has been proven in provisionals, the final occlusal scheme and tooth dimensions can be transferred to ceramics with confidence, completing the rehabilitation in a controlled and repeatable manner.