3.1 Occlusion and Temporomandibular Disorders

Orthofunction

Forces during TMJ function are within an adaptive physiologic range with no pathological change in oral tissues

True

T/F: Malocclusion can still have orthofunction

Dysfunction

TMJ forces exceed the adaptive capacity, resulting in injury in the PDL, resorption or hypertrophic response in surrounding tissues.

Fremitus

A palpable or visible movement of a tooth when subjected to occlusal forces

Primary occlusal trauma

Heavy occlusal forces that exceed the adaptive range in a normal periodontium that causes injury to tissues and bone

Secondary occlusal trauma

Normal occlusal forces exceed capability of periodontium that has been affected by disease

True

T/F: Trauma from occlusion will not initiate periodontitis, but when inflammation is present, it can increase tissue attachment loss and supporting bone structure

Extracapsular

TMD that involves the muscles only and not the TMJ

Intracapsular

TMD that originates in the TMJ

True

T/F: Up to 60% of the population may have TMD disorders, but only a small percentage of these individuals require intervention

Myalgia

Pain originating in the muscles

Trismus

A spasm of the masticatory muscles that is a disturbance of the trigeminal nerve

Spasm

An involuntary contraction of muscle interfering with function

Dyskinesia

Abnormal movement

Bruxism

Grinding

Ankylosis

Abnormal stiffening because of bone fusion

Muscular fibrosis

Scar tissue

Joint adhesions

Occurs when joint cushions start to thin out

Parafunction

Repetitive masticatory activity outside normal range of function, such as bruxism

Bruxism

What is the most frequently described oral parafunctional habit?

40 mm

The interincisal edge to edge measurement should be at least how wide?

8 mm

Side to side and forward movement should be at least how large?

Deviation

Shifting is observed during opening and closing, but returns to normal towards the midline

Deflection

Shifting is observed during opening that becomes greater as opening continues

• Widening of PDL

• Osteosclerosis

• Hypercementosis

What are 3 radiographic indicators of excessive occlusal forces?

Condylectomy

Complete removal of the condyle via surgical therapy

Condylotomy

Partial removal of the condyle via surgical therapy