Static Occlusion

Occlusion

Contact relationships of the teeth resulting from neuromuscular control of the masticatory system (musculature, TMJ, mandible, periodontium)

Physiologic occlusion

• Occlusion-related pathosis is absent

• Minimal muscle hyperactivity, limited stress to system

Traumatic occlusion

Occlusion as the causative factor in formation of lesions

Therapeutic occlusion

• Treatment occlusion

• Counteract structural relationships related to traumatic occlusion

Good occlusion

• Optimal function

• Absence of disease

• Functional forms of teeth

• Arrangement within dental arches

• Relationship of mn to mx dental arch

• Relation of mandible to maxilla

• TMJ, muscles, nerves, ligaments

Factors that contribute to occlusion

• Facial and lingual curvatures

• Contact areas

• Embrasures

• Interproximal surfaces

• Surface contact

• Cusp and fossa apposition

• Cusp and embrasure apposition

• Ridge and sulcus apposition

Functional forms of teeth

Facial and lingual curvatures

Divert food away from the gingiva to prevent it from being traumatized

Crest of curvature on facial surfaces of all teeth

Cervical 1/3

Crest of curvature on lingual surfaces of anterior teeth

Cervical 1/3

Crest of curvature on lingual surfaces of posterior teeth

Middle 1/3

Contact areas

• Positive contact relation M and D

• COC on the proximal surface of crowns where a tooth touches adjacent tooth

• Stabilize the tooth within the alveolus

• Prevent food impaction

• Protect the ID papilla

In all teeth, _____ contacts are more cervical except 44 and 34, and mandibular centrals

Distal

In 44 and 34, _____ contact is more cervical

Mesial

at the same level

Contact area of mandibular centrals

In all anterior teeth except maxillary 3, mesial contacts are in the

Incisal 1/3

Mesial contact of maxillary 3

Junction of incisal and middle 1/3

In all posterior teeth, mesial contacts are at the?

Junction of middle and occlusal 1/3

Which embrasures are larger?

Lingual embrasures

Between 11 and 21

Widest incisal embrasure

Incisal or occlusal embrasures

Shallow incisocervically and narrow faciolingually on anterior, broad on the posterior

Stamp cusps

• Occlude in fossa of opposing teeth well within the perimeter of the crowns of teeth not exceeding 4 sq. mm the amount of tooth contact

• Crush and cut food

• Maintain vertical dimension of occlusion

• Provide centric stops in centric occlusion

Shear cusps

• Guiding cusps during contact with stamp cusps

• Minimize tissue impingement

• Shear the food, act as grabbing cusps

• Give stability to mandible — providing tight and definite occlusal relationship when teeth occlude (maximum intercuspation)

Shear cusp of mx → Stamp cusps of mn

Tooth Contact A

Stamp cusp of mx → Stamp cusp of mn

Tooth Contact B

Stamp cusps of mx → Shear cusps of mn

Tooth Contact C

Tripodization

For every occluding tooth, three contact points are seen, this is called?

*this directs occlusal surfaces to the long axis of the tooth

counter contact; reciprocating force

For every tooth contact on an inclined surface, there is a _____ on another and opposite inclined surface, and a _____ to equalize occlusal forces

Cusp and fossa apposition

Most effective stabilizer of alignment

ML cusp; lingual embrasures

In cusp and embrasure apposition, ____________of all mandibular molars are in apposition with the _______________ of the maxillary molars

Ridge and sulcus apposition

Triangular ridges of the buccal cusps of mx molars → buccal grooves of the mn molars

Ridge

Junction of 2 surfaces

Occlusal table

Area contained within the M and D edges of the occlusal surface

Distofacial cusps 

Mandibular first molars have extra long triangular ridges on the _____ causing deviation of the central groove

Which cusp is larger?

Mesiopalatal cusp

DCR of the MLC of 16/26 + Triangular ridge of the DBC 

What forms the oblique ridge?