When the laboratory is articulating upper and lower casts for night guard construction, cusp interaction of certain teeth will determine the thickness for maxillary guards. The attempt by the Laboratory and the request by the doctor are usually for a guard that has a FLAT-PLANED surface or appearance to accommodate the Bruxing movements of the mandible. This keeps all teeth in occlusion with the guard during all mandibular movements. In about half the cases this is possible. Other times, the Bruxism appliance is designed with Anterior Guidance also known as "Canine rise"; all posterior teeth disclude during excursive and protrusive movements. Just before waxing up a night guard for processing, the lab sets the articulating pin to accommodate the vertical opening needed to construct the guard. At this time, clearance is determined for protrusive and excursive movements in the mandible. Most attention is drawn to the canines as they seem to extend the farthest into the bite plane and interfere greatest during lateral movement. (This step can be identified prior to taking the impression and appropriate measures can be taken by Doctor in the way of trimming the cusp tips of #6 and #11 only slight to offer up a little more room.) The alternative is a slightly thicker appliance. The other area that demands attention in about half the cases is: Maxilla – M L cusps of #2, #15 Mandible – D B cusps of #18, #31 During lateral excursion (the Bennett movement) these cusps play a very close game. The guard will usually display signs of wear and thinning in these areas before any other, at which time the guard will need to be remade. To add acrylic in these areas at this time would only put the guard into malocclusion. The entire guard (arch-form) needs to be rebuilt. Again, some preemptive trimming would not hurt. A secondary option would be making a mandibular appliance and relying on complete anterior guidance. Please contact Tony for further specific information about this. |
| Depot Dental Lab Inc. |
| BRUXING BLUES |
