In the last week I have embarked on two separate restorative cases where the vertical dimension is being opened. I can remember when I was in dental school and first out in practice and I believed that altering someone’s vertical dimension of occlusion should never be altered. Since then I have come to understand more about the process and what the risks and the benefits are. The definition of Vertical Dimension of Occlusion is: a term used in dentistry to indicate the superior-inferior relationship of the maxilla and the mandible when the teeth are situated in maximum intercuspation. We measure the patient’s vertical dimension from a fixed skeletal reference on the maxilla to one on the mandible with their teeth together in their acquired bite.
The common fears of opening vertical are that the patient will develop joint or muscle pain. Based on the scientific research their is very little risk of either of these happening. Another common risk is difficulty adapting to the new vertical and phonetic issues. When we open a patient;s vertical we do not want to consume all of their freeway space, and the change must be tested prior to making it in final restorations. Unfortunately, using a removable appliance is a poor way to test a patient’s ability to adapt to opening their vertical. A true test requires using direct composite overlays, or restorations or provisionals, something the patient can not remove and must function in all of the time. If challenges with phonetics or adaptation are encountered, the vertical or tooth contacts must be corrected to alleviate them. The last risk is that the change will not be long lasting and the vertical will return to it’s previous amount through tooth movement or osseous adaptation. This risk is often does not have an impact on the function or esthetics of the patient so is not clinically relevant. One way to manage this risk is to follow the patient in their provisional restorations for 6-9 months prior to completing the case.
Opening vertical dimension of occlusion for me occurs for two primary reasons. The first is restorative clearance. When working with patients with severe wear, multi-level occlusal planes and insufficient tooth structure for restorations opening the vertical can simply their treatment, reduce the risks of restoration and correct function and esthetics. Another common reason I consider opening the vertical is to correct upper anterior esthetics and add tooth length while being able to maintain of shallow the inter-incisal angle or anterior guidance to reduce functional risks. I am cautious about altering vertical, and do not utilize it unless it improves the potential outcome of a case, but I also do not shy away from considering it as a treatment option.. One thing to keep in mind when considering this option versus others like ortho or crown lengthening is the patient’s preferences and the number of teeth that will require restoration that do not need them for health, structural, esthetic or functional reasons.