Diagnoses

Loss of vertical dimension of occlusion

Establishing this diagnosis

Tooth enamel is extremely durable, and under normal function will provide a lifetime of service without measurable wear. Concentrated forces can accelerate wear of tooth enamel, and primarily occurs in two situations: normal forces on poorly aligned teeth; and heavy forces on normally aligned teeth.
Learn more: Diagnoses › Bruxism
Learn more: Diagnoses › Malocclusion

When attrition (wear) is severe, a patient will often complain to their dentist about "short teeth". Often, these are patients who have not undergone regular dental care in the past, and no one has been monitoring the demise of the teeth. Some patients report pain in the jaw joints or facial muscles. Another common complaint is frequent muscle tension headaches, and fatigued jaw muscles. Many people attribute the shortened lower face height to age, missing the connection to their short (or lost) teeth.
Learn more: Diagnoses › Attrition

The challenge for dentists is to recognize and treat the early signs of bruxism before the damage becomes as severe as that shown in Figure 1. It is also important to be proactive about preventing loss of teeth, and to make a priority of replacing teeth when they are lost.

One thing that complicates a diagnosis of bruxing is determining when the damage occurred, so that restorative procedures to correct the vertical dimension of occlusion can be successful long term. Many patients go through stressful periods in their lives when bruxing is a problem. Sometimes the habit resolves on its own after the stressful events have passed. Another problem is that bruxers frequently are unaware of the habit, which may occur while they are sleeping.

Home screening tests are available for determining whether a bruxing habit is active. They are purchased directly from the manufacturer, and consist of single-use EMG (electomyography) strips applied to the corners of the jaw over the chewing muscles, that record muscle activity on a permanent electrochemical indicator as the patient sleeps.

Photographing the extent of wear at checkups is one way to establish whether or not a patient is actively bruxing. Another way is to make casts of the teeth of a suspected bruxer, and compare them with the patient's actual teeth over time.
Learn more: Procedures › Photographs

Diagnosing bite collapse in patients who have lost multiple teeth can involve use of articulator-mounted study casts of the teeth, visual evaluation of the patient's dental arches, facial profile, and soft tissue measurements (e.g. distance between the point of the nose and tip of the chin); resting and smiling lip positions; bite relationship ("occlusion"); and use of sophisticated neuromuscular monitoring equipment, although the latter technique continues to be highly controversial and hotly debated.
Learn more: Glossary › Articulator
Learn more: Procedures › Casts

Proponents of neuromuscular dentistry state that they can measure abnormal muscle activity, caused by shortening of the masseter muscles as the jaws rotate together. Detractors claim neuromuscular monitors can be used to convince patients to undergo treatment, when they have no symptoms or other significant signs of bite collapse. Before investing the time and tens of thousands of dollars on dental rehabilitation procedures, be sure you understand your diagnoses, as well as the risks, intended benefits, consequences of no treatment, and treatment options available to you. Also, be sure you have a good feel for the clinical urgency for treatment. If you do not understand each of these important variables completely after talking it over with your dentist, it is a good idea to get a second opinion.