Rationale
1. Teeth are loaded about 20 minutes daily
2. Average physiologic anterior resting space is 4mm +/-1 (agonist/antagonist balance)
3. MAPA averages 2mm of thickness at cuspid discluding elements
4. MAPA engages on patient’s lower cuspids during bruxing etc. Passive (no contact) otherwise
5. When the MAPA is engaged (parafunctional activity, etc.), The bicuspids and molars have no PDL stimulation, the temporal muscles are all but shut down .
• Masseter and medial pterygoid muscle function reduced by over 70% by decreasing leverage. Contact is far away from fulcrum and force (condyles and muscles)
• Bilateral balanced cuspid contact in protrusion. Ideally 4mm in protrusion and lateral runs
• Flat, or nearly so, the cuspid discluding elements prevent isometric forces to lateral pterygoid movements similar to skates on ice
• Teeth and condyles can reach their “home” or neutral zone by removing posterior dental contact. This also relaxes muscles.
• Prevents sinus bones from being loaded or flexed
• Compression on nerves and vessels reduced throughout face and TMJs