There are several techniques to establish a new plane of occlusion. Dental-Facial jigs using a facebow, Kois dento-facial analyzer, and several more from various articulation systems are commonly utilized. This writing will show the technique of using the HIP impression technique for mounting maxillary casts in conjunction with a Digital Stick Bite™ to verify the accuracy of the mounting. Several techniques listed above can be accurate; however, they are very subjective to the accuracy of the X-Y and Z axis recorded for transfer to the lab and be unique to each skull. Lab data suggests that less than 25% of the mounting records sent to Ocean Ceramics are inaccurate and flawed. When developing a new smile or maxillary arch of prosthetics, it is critical that the X,Y and Z axis are recorded properly and consistently with a very high percentage of accuracy.
When treatment planning edentulous reconstructions like All-On-4 implant cases, Full Zirconia arches on implants or just non-retained denture cases, it is critical to establish a level foundation within the skull to evenly distribute forces received from the function of the mandible. “When the plane of occlusion is related to the sphenobasilar synchondrosis in an optimal three-way alignment, the vectors of force created by the closing muscles are directed to the center of the cranium in a symmetrically balanced way, causing enhancement of cranial motion and creating harmony within the brain, craniosacral mechanism, and the rest of the central nervous system. Thus, harmony and homeostasis is maintained and overall body health is enhanced.”1 It is critical that any mounting record is verified with another record prior to proceeding with any prosthetic design and treatment at the planning/design phase and subsequent stages. The 2 critical records required for this technique is the HIP impression and Digital Stick Bite™ photograph.
- The Digital Stick Bite™ photograph is a portrait image, cheeks retracted, teeth slightly apart to see plane of occlusion, hair behind the ears, patient stares directly into lens, and the photographer aims the lens parallel to the anterior-posterior (Z) axis.
- The HIP ( Hamular notch-Incisive Papilla ) impression is best taken with an alginate replacement impression material ( Status Blue from DMG ) which enables the lab to perform multiple pours maintaining accuracy of casts for various purposes. Just in case the hamular notches are not captured with clarity on first impression, reline the most posterior border area with a small amount of PVS bite registration material ( O-Bite from DMG ) and re-insert the impression for 30 seconds.
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