Determinant Of Occlusion

Front 1

Static vs. Dynamic Relationship between mandible and maxilla

Back 1

STATIC – HINGE AXIS which is less than 20 mm of opening; DYNAMIC – BETWEEN HINGE AND TRANSLATION at over 20mm

Front 2

Determinants of Occlusion include

Back 2

1) CENTRIC RELATION JAW POSITION – IMPORTANT, 2) Skeletal structure, 3) Anatomy of TMJ, 4) Postural muscle, 5) Vasculature, 6) Neuromuscular, 7) Functional and parafunctional movement, 8) GEOMETRY OF CURVILINEAR (Spherical theory) AND RECTILINEAR (MOST COMMON) MOVEMENT

Front 3

Hanau’s Quint

Back 3

Formulas that established articulation in the Anaotmic (natural teeth), semi-prosthetic (PD) and Full Prosthetic (Denture)

Front 4

What are the 3 planes movement/controlling forces?

Back 4

1) Front – Condylar guidance angle (CG angle) and Anterior Guidance Angle (AG angle) may be different, 2) Sagittal – MOST USEFUL, 3) Horizontal – key to understanding laterotrusive movement, Bennet Angle, Wide centric, and cusp position

Front 5

What are the 2 VERTICAL controlling forces (Mutual Protective Occlusion)?

Back 5

Anterior and Posterior

Front 6

Describe how (both) vertical forces lead to stable occlusion?

Back 6

POSTERIOR teeth and TMJ stabilize occlusion during maximal intercuspation and ANTERIOR TEETH stabilize excursive movements

Front 7

What structures are responsible for the POSTERIOR vertical forces?

Back 7

2 TMJs, head of condyle, and TMJ disc

Front 8

What are the goals of POSTERIOR vertical forces

Back 8

1) Good function, Range of Motion and Stability, 2) Establishing Occlusal Vertical Dimension, 3) Closure Stoppers

Front 9

Closure Stoppers

Back 9

Posterior teeth and TMJ provide vertical stops

Front 10

What are some ways vertical controlling forces can be lost (9)?

Back 10

1) Posterior caries, 2) Occlusal wear, 3) Fracture of posterior cusps, 4)Extraction of posterior teeth, 5) Anterior teeth fremitus (vibration), 6) Flaring of teeth, 7) Diastemas, 8) Failure of occlusal stability system, 9) Compressive TMJ disc failure

Front 11

Overall what makes cusps taller (3)? What makes them shorter?

Back 11

TALLER – Steep TMJ wall and Condylar Guidance (CG) angle, Greater Vertical Overlap, Flatter curve of Spee/Wilson; SHORTER – Greater side shift/Bennett movement, Greater Overjet

Front 12

Relationship between TMJ wall steepness and cusps? Steepness of CG angle and cusps?

Back 12

The steeper the wall, the taller the cusps; The steeper the CG angle the taller the cusps

Front 13

What are the articulating structures of the TMJ and part of the skull are they located?

Back 13

1) Glenoid (mandibular) fossa and articular eminence in the squamous portion of the temporal bone

Front 14

What is the goal of anterior guidance?

Back 14

Causes teeth to be slightly out of contact when biting in CR (hinge axis) or MI; causes posterior disocclusion

Front 15

What can go wrong with dentures?

Back 15

1) Collapse of Occlusal vertical dimension, 2) Wear of acrylic denture teeth, 3) Residual ridge resorption (RRR), 4) Collapse of TMJ meniscus, 5) Degenerative Joint Disease (DJD), 6) No CR or no edge to edge contact in MI, 7) Fractured condyle, 8) Class III protruded mandible

Front 16

Denture Occlusion in anterior vs natural teeth occlusion?

Back 16

Natural occlusion is 45 degrees but dentures are 55 degrees (called COUPLING)

Front 17

What is overbite vs overjet?

Back 17

1) OVERBITE – Vertical overlap, esp. of maxillary incisor or mandibular incisor; 2) OVERJET – Horizontal projection of the teeth beyond the opposing tooth

Front 18

What happens with a greater vertical overlap?

Back 18

1) There is less horizontal overlap, 2) There are taller cusps in the posterior, increasing vertical dimension during protrusion - IMPORTANT, 3) There is more protection of the posterior teeth by the anterior teeth

Front 19

What happens with greater overjet?

Back 19

SHORTER CUSPS since there is less space in the posterior during protrusion – IMPORTANT

Front 20

What 3 points do the curves of Spee and Wilson touch?

Back 20

1) Condylar surface, 2) Posterior cusp tips, 3) Incisal point

Front 21

What is tangent to the curve made by Spee and Wilson

Back 21

Plane of Occlusion

Front 22

What results from variation of the curve and Plane of Occlusion?

Back 22

Variations in cusp height; They are VERTICAL CONTROLS – The flatter the plane (curve) the taller the cusp height can be; IMPORTANT

Front 23

Significance of horizontal plane

Back 23

The vertical axis passes through this plane and accounts for the greates influence on occlusal anatomy than any other factor

Front 24

What is Bennett movement? Bennett angle?

Back 24

Bennett movement - a bodily side shift of the condyle on the working side in conjunction with rotation (GREEN);

Bennett Angle - The angle made by the sagittal plane and a line drawn from the point of origin of the balancing (non-working) condyle to the final position (RED)

Front 25

How does Bennett movement affect cusp height?

Back 25

The greater the side shift, the shorter the cusps will be