Dental Hygiene Instrumentation and Techniques

Vocabulary flashcards covering key terms from the lecture notes on dental hygiene instrumentation, grasp, fulcrums, mirror use, and powered scalers.

Functional Shank

The portion of the shank from the working end to the last bend; helps orient the working end on tooth surfaces.

Terminal Shank

The shorter portion of the functional shank closest to the working end; helps orient and position the working end correctly.

Shank

The part between the handle and the working end; varies in length, curvature, and rigidity.

Working End

The part of the instrument that contacts the tooth; can be wire-like, rod-like, or blade.

Wire-Like Working End

A thin, flexible tip used for calculus detection and exploration.

Rod-Like Working End

A thicker, cylindrical tip used for probing or scaling tasks.

Blade (Working End)

A flat cutting edge used for scraping calculus from tooth surfaces.

Single-Ended Instrument

An instrument with one working end.

Double-Ended Instrument

An instrument with two working ends that can perform different functions in one tool.

Balanced Instrument

An instrument whose working end is centered on the long axis of the handle to improve control and reduce fatigue.

Knurled Handle

A textured handle designed to resist slipping, enhance tactile sensitivity, and reduce fatigue.

Intraoral Fulcrum

A fulcrum placed inside the mouth on a tooth surface to provide support and stroke control; preferred for beginners.

Extraoral Fulcrum

A fulcrum placed outside the mouth to provide stability in certain techniques.

Fulcrum

A point of support for the hand during instrumentation that enhances control and safety.

Palm Grasp

Handle held in the palm; used when the mirror is not being used.

Pen Grasp

A precision grasp using the thumb and finger; not used in dentistry due to ergonomics.

Modified Pen Grasp (MPG)

Three-finger grasp (thumb, index, middle) with the ring finger acting as the fulcrum; improves control and tactile feedback.

Dominant Hand

The hand used for primary instrumentation tasks.

Non-Dominant Hand

The hand used to assist, retract tissues, or stabilize the mirror.

Indirect Illumination

Using the dental mirror to reflect light onto intraoral structures to improve visibility.

Indirect Vision

Using the dental mirror to view structures not directly visible.

Retraction

Using the mirror to move soft tissues away from the working area to improve access and visibility.

Transillumination

Using the mirror to reflect light through anterior teeth to reveal caries or fractures.

Explorer

A wire-like instrument used to detect calculus and tooth surface irregularities.

Periodontal Probe

A rod-like instrument used to measure periodontal pocket depths.

Sickle Scaler

A blade-like instrument used for calculus removal from supragingival and easily accessible subgingival surfaces.

Sonic Scaler

Powered scaler driven by compressed air; lower frequency with elliptical tip movement.

Magnetostrictive Ultrasonic Scaler

Powered scaler using metal strips or ferric rod to vibrate the tip in an elliptical pattern; has multiple frequency options.

Piezoelectric Ultrasonic Scaler

Powered scaler using ceramic rod/transducers with linear tip movement; operates via electrical energy.

Amplitude

The distance of the tip movement in powered scalers; determines power output.

Frequency

The speed of tip movement (cycles per second, measured in kHz); affects cleaning efficiency.

Cavitation

Formation and collapse of microscopic bubbles in irrigant that help destroy bacterial cell walls.

Lavage

Continuous flushing action from the water spray in powered instruments to remove debris and microorganisms.

CTD (Cumulative Trauma Disorder)

Injuries from repetitive motions or awkward postures; preventable with ergonomic instrument design.

Indications for Powered Instruments

Primary uses include efficient calculus removal and access in challenging areas.

Contraindications for Powered Instruments

Systemic conditions such as communicable disease, high susceptibility to infection, or respiratory risk.

Mechanism of Action (Powered Instruments)

Combination of mechanical vibration, irrigation, and cavitation to remove calculus.

Double-Ended Instrument Example

A Shepard’s Hook Explorer paired with a Periodontal Probe to provide two functions in one instrument.

Transillumination Function (in mirror use)

Using light transmitted through teeth to help detect caries or fractures.

Larger-Diameter, Lighter-Weight Handles

Benefits include reduced fatigue and CTD risk and enhanced tactile sensitivity.