FAST REVISION
Occlusion Concepts
| Term |
Definition / Clinical Insight |
| Balanced Occlusion |
Simultaneous bilateral contacts during eccentric movements; achieved
by grinding lingual inclines of facial cusps on the balancing side. |
| Christensen’s Phenomenon |
Posterior separation during edge-to-edge anterior contact in
protrusion. |
| Curve of Spee |
Anteroposterior curvature of occlusal plane; compensates for
vertical overlap. |
| Curve of Wilson |
Mediolateral curvature of posterior teeth; helps in bilateral
balanced occlusion. |
| Monson’s Sphere |
Ideal occlusal curvature; 8-inch diameter sphere concept. |
Jaw Relation Records
| Step/Concept |
Details |
| Vertical Dimension at Rest (VDR) |
First step in jaw relation recording; measured when mandible is at
rest. |
| Vertical Dimension of Occlusion (VDO) |
Distance between maxilla and mandible when teeth are in contact. |
| Centric Relation (CR) |
Condyles in anterior-superior position in glenoid fossa; independent
of tooth contact. |
| Terminal Hinge Position |
Pure hinge movement; reproducible and used for CR records. |
| Condylar Inclination |
Angle of condylar path; determined using protrusive records. |
Reference Planes & Landmarks
| Landmark |
Purpose |
| Camper’s Line |
From ala of nose to superior border of tragus; used to align
occlusal plane. |
| Beyron Point |
13 mm anterior to tragus on tragus–canthus line; used in facebow
transfer. |
Articulators & Theories
| Device/Theory |
Application |
| Monson Articulator |
Based on arbitrary motion theory; simulates mandibular movements. |
| Arcon vs Non-Arcon |
Arcon: condylar elements on lower member; Non-Arcon: condylar
elements on upper member. |
| Facebow Transfer |
Records spatial relationship of maxilla to condyles; essential for
mounting casts accurately. |
Occlusion & Jaw Relations synopsis
- Facebow (accurate hinge axis): Fully adjustable rods.
- Facebow use: Multiple unit restorations.
- Posselt: Described border movements.
- Fisher angle: Intersection of protrusive & non-working condylar paths
(~5°).
- Curve of Spee: Anterior to posterior curve.
- Von Spee curve: Natural dentition.
- Sharp tooth pain: A-delta fibers.
- Sound change with anterior teeth position: “F” sounds.
- Centric relation: Posterior to intercuspal by 0.5–1 mm.
