At the Occlusion in Clinical Practice workshop, we gather multiple bites taken on each participant by his or her two clinical partners. Each “doctor” in the exercise gathers a bite record taken using bilateral manipulation, a Lucia jig, and a leaf gauge. We use the collection of these bite records not only to teach and practice the techniques but also to compare our mountings to our intraoral observations and look at cross operator and cross technique reliability.
In the Occlusion workshop that ended on March 15 we reached a new milestone. This group of participants set a new record for mountings matching the findings in the mouth, 33 of 36 participants, or 92 percent found their models duplicated the contacts noted intraorally. The three who did not match were all patients with joint and muscle issues, just the type of patient we expect not to reliably gather a joint position from.
We believe that the reason for this high degree of correlation is due to the use of the model stabilization kit for holding the casts together, an addition that we implemented at this Occlusion workshop with kits provided by Great Lakes Orthodontics. A wire is connected to the casts at four points with cyano-acrylate gel to protect the models from the movement that occurs with mounting stone expanding.
Want to match what you find in the mouth? Here are some tips:
• Gather excellent impressions and pour them quickly if you are using alginate
• Adhere to the water/powder ratios recommended by the manufacturer
• Use a vacuum mixer
• Use die stone rather than plaster or Buff stone
• Don’t flip the poured model over
• Let the stone set completely before removing from impression
• Trim the material on the bite fork
• Trim the bite records
• Stabilize the models together
