Adaptation Strokes Flashcards
What is motion activation?
Moving the instrument to produce an instrument stroke against the tooth using wrist and digital movements
What is wrist motion activation?
Rotating the hand and wrist together to provide the power for a stroke
Most common
What are the uses of wrist activation?
Used for all calculus removal with hand activated instruments
Creates the most power and causes the least amount of fatigue
What is digital motion activation?
Moving the instruments by flexing the thumb, index and middle fingers.
Push-pull movements
Uses of digital motion
Used primarily with ultrasonic instruments when no physical strength is required.
Not recommended for calculus removal with hand instruments.
Good for restricted areas such as furcations
What is the purpose of rolling the instrument handle?
Maintains precise contact of the working end to the tooth surface as it moves around it.
The drive finger (either thumb or index) is used to turn the instrument
What is pivoting?
Tiny movement to reposition the hand while the fulcrum supports the hand and arm by balancing on the fulcrum finger
What is the purpose of pivoting on the fulcrum?
Maintaining adaptation as the working end moves around the tooth. Used mostly when moving around a line angle onto a proximal surface
What is adaptation?
Positioning of the first one to 2 mm of the working ends lateral surface in contact with the tooth
What are the three imaginary sections of the working end?
Leading third, middle third, heel third
What is the leading third for a curette or a scaler?
The toe for a curette and the tip for a scaler
For correct adaptation where should the leading third be?
Always in contact with the tooth surface. Sometimes the middle third as well.
Heel third should never be in contact with the tooth surface
Characteristics of instrumentation strokes
The active moving the working end against the tooth surface
Instrumentation strokes can be calculus removal/root debridement strokes or exploratory strokes to detect calculus
What is junctional epithelium?
Soft epithelial tissue forming the base of a gingival sulcus/pocket
Consider it’s location moving across the tooth surface, cutting edges could injure the junctional epithelium
What are the three different strokes directions
Vertical, oblique, horizontal
Describe vertical strokes
Used mostly on anterior teeth on the facial, lingual and proximal surfaces.
On posterior teeth they are used on mesial and distal surfaces
Where are obliques strokes used?
Facial and lingual surfaces of posterior teeth
Where are horizontal strokes used?
Line angles of posterior teeth, furcation areas and deep, narrow pockets
Also used on narrow root surfaces of anterior teeth
What are the three types of instrumentation strokes?
Assessment stroke, calculus removal stroke, root debridement stroke
What are assessment strokes used for?
Evaluating the tooth surface
To locate calculus deposits
Feather light movements that contact the tooth but without any pressure
Describe calculus removal strokes
Used to lift calculus deposits off the tooth surface with curettes and scalers
Tiny, biting strokes used to snap calculus deposits off of teeth. Moderate pressure applied
Describe root debridement strokes
Used to remove residual calculus deposits, bacterial biofilm and byproducts from root surfaces exposed because of gingival recession and root surfaces deep within perio pockets
Characteristics of root debridement strokes
Lighter shaving stroke of moderate length. Used with curettes and light pressure against the tooth surface
Conservation of cementum facilitates tissue healing
Pathological potential of sub gingival calculus deposits
Covered with disease causing bacteria
Contributes to perio disease
Important for controlling disease
Surface of calculus is irregular at microscopic level
How do we visualize sub gingival calculus
Understanding periodontium in cross-section
Use radiographs
Explore root surface
Know root anatomy
What is insertion?
The act of gently sliding the working and beneath the gingival margin into the sulcus
What is angulation?
Relation between the face of the working end and the tooth surface
What is the angulation for insertion?
Face to tooth anguulation should be between zero and 40°
A.k.a. a closed angle
Position the face as close to the tooth surface as possible
Where is the get ready zone?
Middle third of the crown
What is the correct regulation for calculus removal?
Greater than 45° and less than 90°
Ideally in the 60 to 80° range. Cutting edge will bite into calculus deposit and snap it from the tooth
What is stabilization?
Act of locking joints of ring finger and pressing fingertip against the tooth surface.
Provides control of stroke
What is lateral pressure?
Created by applying pressure with index finger and thumb inward against the instrument handle
Apply before and during instrumentation stroke
How much pressure should be used for assessment, calculus removal and root debridement strokes?
Assessment – light touch
Calculus removal – firm pressure
Route debridement – less pressure than calculus removal
What may happen due to inadequate lateral pressure?
Incomplete calculus removal or burnished calculus
In what direction are calculus removal strokes always made?
Coronally, away from the soft tissue base of the sulcus or pocket
Removing large deposits
Remove in sections, one section of the deposit at a time
All deposits from one tooth should be removed before moving onto a second
What causes the burnishing of calculus?
Removing the calculus deposit in layers. Removing the outer most layer will leave the deposit with a smooth surface
Correct angulation will prevent this from occurring
What are the effects of burnished calculus?
More difficult to detect and remove
Retain biofilms that are associated with inflammation of periodontal tissue
What may the results be of angulation errors?
Greater than 90° results in tissue injury
Less than 45° results in burnished calculus
