Operative Instrumentation

These flashcards cover key terms and concepts related to operative instrumentation in dentistry, focusing on handpieces, burs, and rotary instruments.

Operative Dentistry

The branch of dentistry that deals with the restoration of teeth and the treatment of dental caries.

Handpieces

Devices that hold dental burs and are used to perform various procedures in dentistry.

Rotary Instrument

An instrument that uses rotational motion to cut or shape a substance, commonly employed in dental procedures.

High Speed Handpiece

A type of handpiece that operates typically at speeds above 200,000 rpm, used for fast tooth reduction.

Bur

A rotating cutting tool used in dentistry to remove or shape hard tissue of the tooth.

Dental Burs

Tools that attach to handpieces and are used for cutting or polishing hard tissues.

Tungsten Carbide Burs

Durable dental burs that are harder than steel and provide a smoother finish at high speeds.

Diamond Burs

Burs bonded with diamond particles, used for grinding hard tissues like bone and enamel.

Speed Classification

The measurement of rotary instruments based on their operating speed, categorized as slow, intermediate, or high speed.

Cutting Recommendation

Guidelines for the optimal use of different types of burs and handpieces during dental procedures.

Mechanical Vibration

A phenomenon that can occur with extended use of dental instruments, potentially causing discomfort for patients.

Thermal Trauma

Damage to tooth pulp caused by excessive heat during dental procedures, often associated with rotary instruments.

Bur Design

The specific characteristics and features of a bur that determine its cutting efficiency and effectiveness.

Soft Tissue Precautions

Measures taken to protect soft tissues in the mouth during dental procedures, reducing the risk of injury.

instrument nomenclature

order suborder class subclass

cutting instruments

self limited in cutting, can remove large pieces, precise, no vibration or heat

basic elements of an instrument

handle/shaft, blade/nib, shank

why are instruments angulated

better control, force distribution, efficiency, and access

3 number system

width of blade in 1/10smm

length of blade in mm

angle of blade from shaft

4 number system

width of blade in 1/10smm

angle of cutting edge 

length of blade

angle of blade to shaft 

factors effecting control

large blade

minimum bends

cutting edge in direct axial alignment

excavators

sharpen prepared walls by removing decay

4 subtypes: hoes, hatchets, angle formers, spoons

hoe

excavator common in class 5 gold restorations 

primary edge perpendicular to blade axis 

used to develop internal form 

hatchet

bi-beveled with cutting edge in same plane as long axis of handle

sharpens internal line angles ad prepare retentive walls 

angle former

man angled excavator used to create an angle other than 90 degrees

refines internal angles creating retention

used with push motion

left side is for left angles, right side is for right angles.

spoon excavator

curved blades with smooth/claw edges to remove decay and debris from cavity preparations. They are designed for both excavating and shaping the cavity.

chisels

cutting enamel 

straight or slightly curved

gingival marginal trimmers