All dentists occasionally have patients who return a few days after a new restoration has been delivered complaining of sensitivity, pain, or that the bite doesn’t feel quite right. Frequently, the cause of the complaint is a simple matter of the occlusion being high on the new restoration. These problems are easy to rectify, but they do create undue distress to the patient and the dentist’s schedule. There’s good news: high occlusion is avoidable 95% of the time if the dentist and team take a few steps to ensure that the occlusion will be correct. Here are seven tips for achieving proper occlusion.
No. 1—Begin with the end in mind (and on camera)
Correct occlusion in single-tooth and/or quadrant dentistry on every restoration begins before the patient is ever numb. First, take a minute to isolate the quadrant or quadrants that will be receiving the restorations and mark the maximum intercuspal bite on the teeth to be restored, as well as at least one additional tooth near the teeth to be restored. Then, study the intensity and location of the marks on the teeth that will not be restored. It is helpful to take an intraoral photograph of these marks. This photograph can be brought up on the monitor as a reference after the restoration is placed to evaluate and dial in the correct occlusion.
No. 2—Ensure that the patient bites naturally
Before we discuss step two, try an experiment in your own mouth. Squeeze your right posterior teeth together. Take note of how that feels. Next, squeeze your left teeth together, again taking mental notes about how it feels. Now, squeeze all your teeth together. When you focused on biting in those three different ways, did your teeth occlude differently? Most dental professionals use a single piece of articulating ribbon and place it on the side that received the new dentistry to evaluate the occlusion on the new restoration. What will most patients do if you put a piece of articulating paper on one side and ask them to tap, bite, or grind? They will typically intentionally bite on the side where the ribbon is, and this is likely not the patient’s maximum intercuspal position (MIP). To offset this tendency of patients to bite differently than usual, place the articulating ribbon on both sides of the mouth and ask them to bite. It is also important to note that when taking the pre-anesthetic snapshot of the patient’s bite, the articulating paper should be on both sides of the mouth as well.
No. 3—Create and maintain a dry field
The most common mistake when recording marks with articulating ribbon is that the dental professional is not operating in a dry enough field. Maintaining a dry field when checking occlusion is not an easy task; it’s a two-person job for most patients. Make sure enough cotton is being used and that your dental assistant understands what a dry field looks like and how to achieve it. Many assistants will blow air on the tooth without simultaneously using suction. This lack of suction while blowing air is a mistake, because blowing air in the mouth without suction blows the saliva around and does not dry the tooth. A useful exercise to teach dental professionals how to establish and maintain a dry field and how quickly it can become wet is to acid etch the occlusal surface on a team member in the office. After 30 seconds, rinse the etch from the teeth and show him or her the desiccated enamel. Then have your staff members experiment with their technique to keep the desiccated enamel dry. This practice affords them real-time feedback about how to keep teeth dry, because they can see the moment the teeth get wet, as the chalky surface becomes shiny when wet.
No. 4—Mark MIP
Once a dry field is achieved, it is the time to evaluate your MIP bite. Place the articulating paper on both sides of the mouth and say to the patient, “Bite together tapping your teeth twice up and down, tap, tap.” If they start grinding, ask the patient not to grind but instead tap up and down, with all teeth together. Usually, they will get the hang of this quickly. Once they have it, adjust the restoration as needed. When the fit appears appropriate, look at the marks on the other teeth in the area. Do those marks match the photograph you took prior to anesthetizing the patient? If the answer is yes, move on to checking the excursive movements. If the answer is no, keep adjusting the restoration until the other teeth match the photograph.
No. 5—Check excursive movements
Two issues commonly occur when checking excursive movements: the dental professional does not coax the patient to move far enough in all directions (left, right, and forward going into crossover), and using only one color of articulating ribbon to check both MIP and excursive movements. Both mistakes will lead to interferences that are likely to cause sensitivity to the newly restored tooth.
No. 6—Capture full range of movements
When asked to grind their teeth or move right, left, and forward, very few patients will travel their entire range of motion in these directions. With a little coaxing and patience, however, we can get most patients to comply, but there will still be some who do not understand the request. This step is definitely worth the effort. The goal is simple enough: we do not want any marks in any excursive movements on posterior teeth, even if they were present on the tooth before restoration. It is almost impossible to match the excursive interferences that the patient is used to on a tooth.
No. 7—Two colors are better than one
The reason we want to use two colors is so we can distinguish the marks on the tooth and know what’s what. Use a lighter color, such as red, to mark the excursive movements and a darker color, such as blue or green, after the excursive movements with the patient tapping twice. If the field is dry and the patient moved completely around with paper or ribbon on both sides, our job is simple—erase the red. Red on MIP stops will be covered with blue or green, so we will leave those alone and adjust off the red.
These seven tips can help solve 95% of our issues with hyperocclusion and is a much better service to the patient than the adage, “cut it low and hope it grows.” Remember hypo-occlusion is likely to result in a less stable jaw joint and possible TMD symptoms. While there are technologies, such as the T-Scan (Tekscan), that may be more accurate than this system, they require a capital investment in equipment and service contracts. The next time a patient needs occlusal adjustments, try these seven tips to achieve predictable results.
Scott Cairns, DDS, graduated from Creighton University School of Dentistry in 1999. He is a multipractice owner-dentist supported by Pacific Dental Services, a faculty member of the PDS University—Institute of Dentistry, a member of the L.D. Pankey Alumni Association, and a former Spear Faculty Club member.