Dentin Comes in Direct Contact with What Substance Above the Gum

question 21

Multiple Choice

Dentin comes in direct contact with what substance above the gum line?

• A) Enamel
• B) Cementum
• C) The periodontal membrane
• D) Both B and C

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Definitions:

Modulator Valves

Valves that modulate the pressure of fluids in systems such as automatic transmissions and ABS braking systems, for controlled operation.

Reluctor Wheel

A toothed rotor that is driven through a stationary magnetic field to produce an AC voltage; used as shaft and wheel speed sensors.

Exciter Ring

Preferred term by one OEM for the toothed reluctor used in a wheel speed sensor.

Tone Wheel

Tone wheel, in automotive contexts, refers to a component that works with sensors to monitor the speed of rotating parts like the wheels or crankshaft, generating a signal that varies with speed.