Ortho - Stomatognathics Pt.3 (Functional Movement)

It runs laterally and posteriorly around the corner of the mouth, joining other fibers of the buccinator muscle that insert to the pterygomandibular raphe just behind the dentition just behind the dentition.

 

At this point, it intermingles with fibers of the superior constrictor muscle and continues posteriorly and medially to anchor at the origin of the superior constrictor muscles, the pharyngeal tubercle of the occipital bone.

It is relatively one of the best developed structures in the human body at birth. This structure may exert two or three times as much force on the dentition as the lips and cheeks at any one time but the net effect is one of balance as tonal contraction.

The ______ _____ of tooth position proposes that a stable dentition exists in a state of balance-where the net resting pressure of the tongue,lips,cheeks, and periodontium is zero

Factors directly influencing dental equilibrium

Examples of Intrinsic forces

• Tongue

• Cheeks

• Lips

• Habits

• Orthodontic Appliances

Factors directly influencing dental equilibrium

Examples of Extrinsic forces

• Tongue

• Cheeks

• Lips

• Habits

• Orthodontic Appliances

What are the most important factors directly influencing dental equilibrium

• Intrinsic forces by tongue, cheeks and lips

• Extrinsic forces: Habits and orthodontic appliances

• Forces from dental occlusion

• Forces from periodontal ligament

The _______ is the only movable bone in the head and face, and it can only be moved in certain directions because of the limitations of morphology and of the structure of the temporomandibular articulation.

During this movement of the mandible, the articular disk is brought forward by the lateral pterygoid muscle and intimately related capsular ligaments as the condyle rotates against the inferior surface of the disk and as the disk itself glides forward on the articular eminence.

• Opening of mandible

• Mandible closure

• Mandible protraction

• Lateral movement

• Benett movement

_______ and the primary contraction of the _____ ______ _____ are largely responsible for the opening movement.

True or False:

The temporal, masseter and medial pterygoid muscles show a controlled relaxation as the mandible opens. This controlled relaxation serves to make the opening movement smooth.

• True

• False