Andrew’s Six Keys To Normal Occlusion Explained

Andrew’s Six Keys To Normal Occlusion Explained

• Key l—Molar Relationship (lnter-arch Relationship).
• Key 2—Crown Angulations (Mesiodistal Crown angulations/Mesiodistal Tip).
• Key 3—Crown Inclination (Labiolingual Crown inclination, the Labiolingual or Buccolingual Torque).
• Key 4—Absence of Rotations.
• Key 5—Presence of Tight Contacts.
• Key 6—Flat Occlusal Plane.

• Normal occlusion is defied as the contact of the upper and lower teeth in the centric relationship.
• Lawrence F Andrew worked on 120 non-orthodontic models based on which he had discovered six keys of normal occlusion.