Osteology and the Muscles of Mastication Lecture #5

Mandible-lateral, exterior view

Mandible-lateral, interior view

Mandibible-Superior view

Cranium view

Maxilla-Inferior view

Muscles Origin-The stable anchor point of the muscle Insertion-the anchor point that moves when muscle is contracted Action-What happens when the muscle is contracted

Masseter Muscle

Temporalis muscle

Medial Pterygoid

Lateral Pterygoid muscle

TMJ/TMD/MPD

TMJ disfunction-Tempromandibular joint disfunction TMD-Tempromandibular disfunction MPD-Myofacial pain disfunction

Subjective Symptoms Headaches Jaw pain Ringing in the ears Pain with chewing Grinding or clenching of teeth Neck aches Clicking jaw

Objective Symptoms Abnormal wear patterns on the teeth Deviated path of opening or closing Three finger rule Tenderness in muscles, especially the Lateral Pterygoid “Can you chew a piece of gum comfortably” Headaches focusing around the temporalis area or above the eyes

Demographics of disease Women have the problem three times as often as men Problem often occurs after a traumatic event Depression often comes along with TMD High stress people (Type A personalities) Certain jobs which compromise posture. (ie computer jobs)

Clicking of the jaw

Treatment of disease Conservative versus Aggressive therapy Aggressive Surgery Orthodontics Crown and Bridge or new dentures Conservative limiting use of the joint anti-inflammatory drugs physical therapy or massage Exercise splints to manage grinding emotional counseling anti-depressant drugs.

NTI appliance

Methamphetamine-Lower anterior

Methamphetamine-Upper anterior