Principles of Instrumentation Flashcards
(25 cards)
Define palm grasp.
Mirror is placed in your non-dominant hand with the head of the mirror towards your wrist. The working end is close to your pinky.
Define/Demonstrate the modified pen grasp.
- Pinch the handle between index and thumb.
- Side of the pad of your middle finger on the terminal shank.
- Rest the handle b/w your 2nd and 3rd knuckle.
- Light grasp
What are the four uses of your mirror?
Retraction
Illumination
Indirect Vision
Transillumination
What is the number one use of the mouth mirror?
Indirect vision
What is a fulcrum?
The use of your ring finger with your instrument.
What is the function of the fulcrum?
Provides... Stability Leverage Point Blade angulation Prevents injury Reduces fatigue Creates a 1 unit moving system (hand + instrument)
Where is a fulcrum used?
Intraorally, close to the tooth on and incisal or occlusal edge.
What is adaptation?
Rotation and keeping the side of the last 2mm of the working end on the tooth.
How do you determine the correct working end of an instrument?
- Place terminal shank parallel to the tooth.
- Instrument should curve in the direction you wish to scale.
- Handle should extend anteriorly.
What is rotation?
Adaptation. Keeping the side of the last 2mm of the tip properly adapted to the tooth surface. Rolling instrument b/w thumb and index finger.
What is pivoting and where does the pivot originate?
Movements on the fulcrum to maintain the appropriate angle.
What is angulation?
The angle formed b/w the face of the blade and tooth surface.
What is the correct working angle?
60-80 tooth to face “open”
What is the correct insertion angle?
“closed” 30-60 tooth to surface
What are scalers and universal instruments parallel to?
The long axis of the tooth.
Graceys are parallel to what surface on a tooth?
The tooth surface being instrumented.
What happens if the angulation is too closed or less than 60degrees.
“Too closed” burnishes calculus
What happens if the angulation is too open or more than 80 degrees?
Lacerate tissue and failure to remove calculus.
What is activation?
Working stroke that removes calculus using side to side or pecking motions.
What is the stroke length and the stroke direction?
Short controlled 1-2mm vertical or oblique overlapping.
What is channeling?
Systematic pattern of instrumentation strokes.
What is lateral pressure?
coronal and lateral pressure to prevent slipping over calculus.
What direction is your palm positioned when fulcruming?
Apically
Adaptation is what?
rotation
