27. Biomechanics of the masticatory articulation. Articulation cycles – opening and closing.

whats in it

masticatory forces

articulation

biomechanics of the mast apparatus

masticatory muscle force

articulation cucles - openind anc closing

key inffo abt the articulation cycle

masticatory forces

masticatory articulation

biomechaiscs of mast apparatus

masticatory muscle force

Result of the contractions of the masticatory muscles, which move jaw into different directions.
Masticatory articulation:
Appears as a dynamic interocclusal contacts between the occlusal surfaces of the teeth. This leads to the mechanical grinding of the food

Biomechanics of the masticatory apparatus:

a part of the Prosthodontics that studies the biological and mechanical interactions in human body in the stages of mastication
Masticatory muscles force:
the energy that is generated by the contractions of the muscles and moves the mandible. This leads to generation of different occlusal interactions.

Directions of the masticatory forces:

1. vertical

2. horizontal

3. combined

art cycle

mastication cycles is the pathway of the mandible during chewing

• -  opening phase (mandible is depressed)

• -  closing phase (mandible is elevated)

• -  ICP phase (also called “intercuspal phase”)

motion of mastication cycle

the motion of the mastication cycle in adults can be seen as a

0. “tear drop” shape:

   • -  In opening phase, the teeth and the condyle move downward and forward

   • -  During early closing the mandible moves laterally to the desired chewing side

   • -  On the chewing side the condyle moves to upward and posterior position well in advance of the intercuspal phase (SRP) (find out what this is !!!!)

   • -  During the rest of the closing phase reaching the ICP phase the chewing condyle moves slightly forward (0.33mm) and medially (0.2mm) → “Bennett movement”

   • -  The condyle of the nonchewing side lags behind

key info abt the articulation cycle

• There are about 15 chews per food swallow

• -  AEV (average vertical clearance) during chewing is 16-20mm

• -  Lateral displacement during chewing is 3-5mm

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- Men usually chew faster and have shorter occlusal phase (the phase at which food is being crushed and grinded)