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FUNDAMENTALS OF PERIODONTAL INSTRUMENTATION & ADVANCED ROOT INSTRUMENTATION

Comprehensive Postgraduate Theory Examination Notes

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PART 1: ERGONOMICS AND PERIODONTAL INSTRUMENTATION (Module 1)

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1.1 KEY TERMS (Module 1 - Verbatim from text)

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1.2 FOUR ERGONOMIC HAZARDS FOR DENTAL HYGIENISTS

1. Force - physical effort applied during instrumentation
2. Repetitive tasks - performing same motions repeatedly
3. Static posture - holding fixed positions for prolonged periods
4. Awkward posture - deviation from neutral body alignment

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1.3 ERGONOMIC DO'S AND DON'TS FOR SEATED POSTURE

Ergonomic Don'ts:

• Altering body position or equipment in an uncomfortable/painful manner "just to get the job done" - results in musculoskeletal stress
• Mindset that it is acceptable to assume uncomfortable position "just for 15 minutes" - "destined to lead to MSDs"
• Pain and injury results when the body's natural spinal curves are not maintained in a seated position

Ergonomic Do's:

• First, the dental hygienist assumes a neutral, balanced body position, then alters the patient's chair and dental equipment
• Good posture requires the seated dental hygienist to use a neutral spine position that maintains the natural curves of the spine

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1.4 NEUTRAL SEATED POSITION - ELEMENTS

NEUTRAL SEATED POSITION
         |
         +--> Head/Neck: Upright, slight forward tilt (20 degrees or less)
         |
         +--> Shoulders: Level, relaxed (not elevated or rounded forward)
         |
         +--> Back: Maintains natural S-curve of spine; back support used
         |
         +--> Elbows: Close to body sides; at approximately waist level
         |
         +--> Forearms: Parallel to floor or angled slightly downward
         |
         +--> Wrists: Straight (neutral); not flexed, extended, or deviated
         |
         +--> Hips: Slightly higher than knees; thighs slope downward slightly
         |
         +--> Feet: Flat on floor, at least shoulder-width apart
              ("wide base of support")

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1.5 OVERVIEW: PATIENT CHAIR POSITION RELATIVE TO SEATED CLINICIAN (Box 1-1)

• Clinician assumes a neutral seated position
• The clinician establishes a "wide base of support" with feet on floor at least shoulder-width apart
• Patient's oral cavity is positioned at approximately the clinician's waist level
• The neutral seated position is established first, and then everything else - the patient chair, the patient's head, the dental unit light, and other dental equipment - are adjusted to facilitate maintenance of the neutral seated position
• While working, the clinician must be able to gain access to the patient's mouth and the dental unit without bending, stretching, or holding elbows above waist level

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1.6 POSITIONING THE INSTRUMENT TRAY

• Should be positioned within easy reach of the clinician's dominant hand
• Incorrect positioning: patient's oral cavity too high (at midsternum level instead of waist level); bracket table too far from clinician (requires stretching)

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1.7 PATIENT POSITIONS (Head/Chair)

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1.8 DENTAL LIGHT POSITIONING

• For maxillary treatment areas: position of overhead dental unit light ranges from being directly over the oral cavity to a position over the patient's neck
• Position the light at arm's length within comfortable reach
• Ideally, light beam always perpendicular to the floor - but this is not always possible with overhead dental light
• This is why a coaxial illumination source is ideal
• The patient is in a chin-up position
• The direction of the light beam ranges from perpendicular to the floor to a 60- to 90-degree angle to the floor

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1.9 ANCILLARY EQUIPMENT: DENTAL HEADLIGHTS AND MAGNIFICATION LOUPES

Dental Headlights - Coaxial Illumination:

• Light source that is aligned with the clinician's line of vision
• Eliminates shadows that occur with overhead dental lights
• Preferred over overhead unit light for optimal illumination

Magnification Loupes:

• Working distance: distance from clinician's eyes to the oral cavity
• Angle of declination: angle at which clinician's head tilts downward
• Depth of field: range of distances at which image remains in focus
• Field of view: width of area visible through loupes
• Blind zone: area not visible through loupes

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PART 2: CLINICIAN POSITION IN RELATION TO TREATMENT AREA (Module 2)

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2.1 THE CLOCK CONCEPT FOR CLINICIAN POSITIONING

• Clinician's position is described using clock positions relative to the patient
• The patient's head is at the center of the clock face
• 12 o'clock = position directly behind the patient's head
• 9 o'clock (right-handed) / 3 o'clock (left-handed) = directly to the side

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2.2 SEQUENCE FOR ESTABLISHING POSITION ("Me, My Patient, My Light...")

STEP 1: ME
Assume the clock position for the treatment area
           |
           v
STEP 2: MY PATIENT
Establish patient chair and head position
           |
           v
STEP 3: MY EQUIPMENT
Adjust the unit light.
Pause and self-check the clinician, patient, and equipment position
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           v
STEP 4: MY NONDOMINANT HAND
Place the fingertips of my nondominant hand as shown
in the illustration for the clock position
           |
           v
STEP 5: MY DOMINANT HAND
Place the fingertips of my dominant hand as shown
in the illustration for the clock position

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PART 3: INSTRUMENT GRASP (Module 3)

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3.1 THE MODIFIED PEN GRASP

Components of Modified Pen Grasp:

Critical Features:

• Index finger and thumb placed so they are opposite each other on the handle but do NOT touch or overlap
• Middle finger pad rests on shank (not handle)
• Middle finger functions as a tactile sensor - transmits vibrations from calculus deposits to the clinician's fingers
• Ring finger serves as the fulcrum (finger rest)
• The grasp must allow for handle roll (rotation of handle between fingers for adaptation)

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3.2 FUNCTION OF EACH FINGER IN THE GRASP (Examiner Keyword)

INDEX FINGER + THUMB
    --> Control the instrument direction and angulation

MIDDLE FINGER (on shank)
    --> Tactile sensor for detecting calculus and irregularities

RING FINGER
    --> Fulcrum finger / intraoral finger rest
    --> Stabilizes the hand during instrumentation

LITTLE FINGER
    --> Rests close to ring finger; assists stabilization

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3.3 PROPER GLOVE FIT (Skill Application - Module 3)

• Evaluate the modified pen grasps for correct/incorrect finger placement
• Identify what is incorrect and what problems might result from incorrect placement
• Evaluate glove fit for both right and left hands

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PART 4: INSTRUMENT DESIGN AND CLASSIFICATION (Module 8)

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4.1 PARTS OF A PERIODONTAL INSTRUMENT

PERIODONTAL INSTRUMENT
         |
         +--> HANDLE
         |      - Part held by clinician
         |      - Various textures, diameters, weights
         |      - Larger diameter handle recommended for ergonomics
         |
         +--> SHANK
         |      - Connects handle to working-end
         |      - LOWER SHANK: portion of shank nearest working-end
         |        (used for angulation and adaptation assessment)
         |      - Flexibility: rigid, moderately flexible, flexible
         |        (flexible shank = better tactile sensitivity for assessment)
         |
         +--> WORKING-END
                - Active portion of instrument
                - One or two working-ends (double-ended)
                - Contains cutting edge(s), tip, or face

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4.2 INSTRUMENT CLASSIFICATIONS

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4.3 INSTRUMENT SHANK CLASSIFICATIONS

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4.4 WORKING-END TERMINOLOGY

• Face: flat surface of working-end between the two cutting edges (of curets/scalers)
• Cutting edge: junction of the face and a lateral surface; the sharpened edge used to remove calculus
• Lateral surface: side surface of working-end
• Back (back surface): rounded portion opposite the face on a curet
• Toe: rounded end of a curet working-end
• Tip: pointed end of a sickle scaler or explorer

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PART 5: TECHNIQUE ESSENTIALS - MOVEMENT AND ORIENTATION TO TOOTH SURFACE (Module 9)

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5.1 PERIODONTAL INSTRUMENTATION AS A FINE MOTOR SKILL

• Periodontal instrumentation is a fine motor skill (also called a psychomotor skill)
• Fine motor skills are small movements carried out when the brain, nervous system, and muscles work together
• Basically a fine motor skill is about brain-body coordination
• The term skill denotes a movement that is complex and the performance of which requires a lot of repeated practice

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5.2 BUILDING BLOCK SKILLS (Module 1 - Conceptual Framework)

• Precise, accurate performance of the building blocks is essential if periodontal instrumentation is to be effective, efficient, safe for the patient, and comfortable for the clinician
• Research on psychomotor skill acquisition indicates that a high level of mastery in the performance of skill building blocks is essential to successful mastery of periodontal instrumentation
• The building block skills are the foundation that "supports" successful periodontal instrumentation
• These skills should be mastered one-by-one
• Each skill should be overlearned until it can be performed easily and without hesitation
• If building block skills are mastered, then the use of any periodontal instrument will be relatively easy to learn
• Faulty performance: Incorrect performance of even one of the building blocks means that at the very least periodontal instrumentation will be inefficient; most likely faulty performance results in:
  • Ineffective calculus removal
  • Unnecessary discomfort for the patient
  • Musculoskeletal stress to the clinician

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5.3 HANDLE ROLL FOR ADAPTATION

• Handle roll: rotation of the instrument handle between the index finger and thumb during instrumentation to maintain proper adaptation of the working-end to the tooth surface
• Performed with the modified pen grasp
• Requires: correct modified pen grasp, knuckles-up position, ulcrum (ring) finger as a support beam, neutral wrist position
• Purpose: to maintain the working-end in contact with the tooth surface as the instrument moves around curved surfaces and line angles

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5.4 ORIENTATION TO TOOTH SURFACE

The Dental Arches and Tooth Surfaces:

• Teeth are positioned in the dental arches
• Using a periodontal probe and a type of explorer, correctly orient the working-end to the various tooth surfaces of the dentition

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PART 6: TECHNIQUE ESSENTIALS - ADAPTATION (Module 10)

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6.1 ADAPTATION OF THE WORKING-END

• Adaptation: correct positioning of the instrument's working-end against the tooth surface
• The lower one-third to one-half of the cutting edge (or the first 1-2 mm of the tip for explorers) should be in contact with the tooth surface at all times
• Correct adaptation = working-end conforms to the curved contours of the tooth surface

Rule for Adaptation:

• Use the lower third of the cutting edge for adaptation
• Only 1-2 mm of the cutting edge (at the toe/tip) should be in contact with the tooth surface

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6.2 ERGONOMICS OF THE HANDLE ROLL FOR ADAPTATION

• The handle roll is used to maintain adaptation as the working-end moves around the curves of the tooth
• The handle is rotated between the index finger and thumb
• During this handle roll:
  • Correct modified pen grasp is maintained
  • Knuckles-up position maintained
  • Ring finger (fulcrum) acts as a support beam
  • Neutral wrist position is maintained

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6.3 SELECTING THE CORRECT WORKING-END

• For double-ended instruments, one working-end is used for surfaces toward the clinician and the other for surfaces away from the clinician
• The correct working-end is identified by:
  • The lower shank parallel to the tooth surface being instrumented
  • The face of the working-end directed toward the tooth surface

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PART 7: TECHNIQUE ESSENTIALS - INSTRUMENTATION STROKES (Module 11)

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7.1 THE INSTRUMENTATION STROKE

Types of Instrumentation Strokes:

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7.2 CHARACTERISTICS OF THE INSTRUMENTATION STROKE

INSTRUMENTATION STROKE
         |
         +--> ACTIVATION (source of power)
         |      - Wrist-forearm rotation (primary)
         |      - Finger flexion (limited use; for light strokes only)
         |
         +--> STROKE LENGTH
         |      - Short, overlapping strokes recommended
         |      - Long strokes = less control and adaptation
         |
         +--> LATERAL PRESSURE
         |      - Firm pressure for calculus removal
         |      - Light pressure for assessment/detection
         |
         +--> STROKE DIRECTION
         |      - Vertical: most common for subgingival
         |      - Horizontal: concavities, furcations
         |      - Oblique: general scaling
         |
         +--> STROKE PATTERN
                - Overlapping strokes to ensure complete coverage
                - Cover entire tooth surface systematically

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7.3 USE OF PRESSURE DURING INSTRUMENTATION

• Activation: The primary source of power for the instrumentation stroke is wrist-forearm rotation
• Finger flexion alone is inappropriate as the primary source of activation - leads to musculoskeletal problems
• Wrist-forearm activation is more powerful and less fatiguing

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PART 8: PERIODONTAL PROBES AND BASIC PROBING TECHNIQUE (Module 12)

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8.1 THE PERIODONTAL PROBE

Design Features:

• Thin, rod-like working-end
• Blunt, rounded tip
• Calibrated markings at specific millimeter intervals
• Used to measure and assess the periodontium

Types of Periodontal Probes (from text):

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8.2 ASSESSING TISSUE HEALTH WITH THE PROBE

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8.3 READING AND RECORDING DEPTH MEASUREMENTS

• Probing depth: distance from the gingival margin to the base (floor) of the sulcus or pocket
• Clinical attachment level (CAL): distance from the cementoenamel junction (CEJ) to the base of the sulcus or pocket
• Record six sites per tooth: mesiobuccal, midbuccal, distobuccal, mesiolingual, midlingual, distolingual

Formula:

If gingival margin is CORONAL to CEJ:
    CAL = Probing depth MINUS recession

If gingival margin is AT CEJ:
    CAL = Probing depth

If gingival margin is APICAL to CEJ (recession):
    CAL = Probing depth PLUS recession measurement

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8.4 PROBING TECHNIQUE

STEP 1: SELECT CORRECT PROBE
Insert probe with face parallel to long axis of tooth
              |
              v
STEP 2: INSERT AT GINGIVAL MARGIN
Walk the probe around the tooth sulcus
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              v
STEP 3: ANGULATE PROBE
Keep probe as parallel to long axis of tooth as possible
For proximal surfaces: tilt slightly to reach under contact area
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              v
STEP 4: APPLY LIGHT PROBING FORCE
Approximately 20-25 grams of force
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              v
STEP 5: "WALK" THE PROBE
Move probe in 1-mm increments ("walking stroke") 
around the circumference of the tooth
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              v
STEP 6: READ THE MEASUREMENT
Read at 6 sites per tooth
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              v
STEP 7: RECORD
Record highest reading at each site

Key Technical Points:

• Probing force: approximately 20-25 grams (light force)
• The probe tip should remain in the sulcus/pocket throughout the "walking" technique
• Keep probe parallel to long axis of tooth as possible
• For proximal surfaces: tilt probe slightly (10-15 degrees) to walk under the contact area
• The probe tip follows the anatomical contour of the root surface

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8.5 INFORMED CONSENT FOR PERIODONTAL INSTRUMENTATION (Module 12)

• Informed consent must be obtained before periodontal instrumentation
• Includes: informed consent form and informed refusal form
• Patient must be informed of: diagnosis, proposed treatment, alternatives, risks/benefits
• Patient signature required

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PART 9: EXPLORERS (Module 13)

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9.1 EXPLORERS - DESIGN AND TYPES

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9.2 TECHNIQUE PRACTICE - ANTERIOR TEETH (Module 13)

• Position working-end on the tooth
• Use overlapping vertical strokes to explore the entire surface
• Detect calculus: tactile sensation - "bumps," "ledges," "rings," "nodules" against the root surface

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9.3 TECHNIQUE PRACTICE - POSTERIOR TEETH (Module 13)

• More complex shank bends required
• Maintain lower one-third of working-end in contact with tooth surface
• Use overlapping strokes; cover all surfaces systematically

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9.4 TECHNIQUE ALERTS (Module 13)

• Technique Alerts = common errors that compromise explorer effectiveness and patient safety

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9.5 DETECTION OF DENTAL CALCULUS DEPOSITS (Module 13)

Tactile Sensations Produced by Calculus:

• Bumps or nodules: small, isolated calculus deposits
• Ledges: horizontal bands of calculus
• Rings: circular deposits encircling the tooth
• Spurs: spike-like projections
• Smooth, glassy surface: burnished calculus (most difficult to detect)

Classification of Calculus by Location:

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9.6 DETECTION OF DENTAL CARIES (Module 13)

• Explorers also used for caries detection
• Tactile sensation of caries: soft, "sticky" or "catch" sensation as explorer tip enters carious lesion
• Caution: excessive probing force can damage demineralized enamel

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PART 10: TECHNIQUE ESSENTIALS - SUPRAGINGIVAL CALCULUS REMOVAL (Module 14)

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10.1 SUPRAGINGIVAL CALCULUS DEPOSITS

• Located coronal to the gingival margin
• Visible during examination
• May be white, yellow, or brown in color
• Most commonly found near salivary duct openings:
  • Lingual surfaces of mandibular anteriors (near Wharton's ducts / submandibular and sublingual glands)
  • Buccal surfaces of maxillary first molars (near Stensen's duct / parotid gland)

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10.2 RELATIONSHIP OF THE INSTRUMENT FACE TO THE TOOTH SURFACE

Face-to-Tooth Surface Angulation (Critical Examiner Topic):

• Correct angulation for calculus removal: 70 to 80 degrees between the instrument face and the tooth surface
• This is achieved by tilting the lower shank slightly toward the tooth surface

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10.3 APPLICATION OF FORCE FOR CALCULUS REMOVAL

• Calculus removal requires firm lateral pressure against the tooth surface
• Lateral pressure is applied through the cutting edge toward the tooth
• Firm pressure = moderate-to-firm lateral pressure for calculus removal
• Light pressure = for assessment strokes

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10.4 STROKE PATTERN FOR SUPRAGINGIVAL CALCULUS REMOVAL

POSITION WORKING-END
Establish 70-80 degree angulation
          |
          v
APPLY LATERAL PRESSURE
Firm pressure against tooth surface
          |
          v
ACTIVATE STROKE
Use wrist-forearm rotation (primary activation)
Direction: vertical, horizontal, or oblique
          |
          v
SHORT, OVERLAPPING STROKES
Cover the entire tooth surface systematically
          |
          v
RE-EXPLORE
Use explorer to verify complete calculus removal

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PART 11: SICKLE SCALERS (Module 15)

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11.1 SICKLE SCALERS - DESIGN FEATURES

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11.2 TYPES OF SICKLE SCALERS

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11.3 ANGULATION - SICKLE SCALER (Critical Examiner Topic)

• Incorrect angulation: Positioning the lower shank parallel to the mesial tooth surface results in a face-to-tooth surface angulation of 90 degrees = this means the other cutting edge could traumatize the soft tissue and calculus removal will be less efficient
• Correct angulation: Achieved by tilting the lower shank slightly toward the mesial surface. In this position the face-to-tooth surface angulation is between 70 and 80 degrees. With this angulation, the other cutting edge tilts toward the mesial surface and away from the soft tissue

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11.4 APPLICATION OF CUTTING EDGES TO ANTERIOR SURFACES (Module 15)

• The working-end of an anterior sickle has two cutting edges (C1 and C2)
• Facial surface: Cutting edge-1 (C-1) used
• Lingual surface: Cutting edge-2 (C-2) used
• Working-end aimed: tip toward the mesial surface

1. Practice on the mandibular left canine, facial aspect first
2. Position working-end near the midline of the incisor
3. Establish 70- to 80-degree instrument face-to-tooth surface angulation
4. Aim the tip toward the mesial surface of the tooth
5. Continue across the facial surface with overlapping strokes

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11.5 MAINTAINING ADAPTATION TO PROXIMAL SURFACES (Module 15)

• As the instrument moves around line angles onto proximal surfaces, maintain adaptation by rolling the handle
• The handle roll is used to keep the lower one-third of the cutting edge in contact with the tooth surface

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11.6 USE ON POSTERIOR TEETH (Module 15)

• Requires angled shank instruments
• Technique requires careful angulation to avoid tissue trauma
• Sickle scaler tip must NOT be submerged deeply subgingivally - the pointed tip can lacerate the junctional epithelium

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11.7 USE ON PRIMARY TEETH (Module 15)

• Sickle scalers can be used on primary (deciduous) teeth
• Technique modified to account for smaller tooth size

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PART 12: TECHNIQUE ESSENTIALS - SUBGINGIVAL CALCULUS REMOVAL (Module 16)

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12.1 THE SENSE OF TOUCH FOR SUBGINGIVAL INSTRUMENTATION

• Subgingival instrumentation relies heavily on tactile sense (sense of touch)
• The clinician cannot see subgingival deposits directly
• Vibrations from calculus are transmitted through the working-end, shank, and handle to the clinician's fingertips
• The middle finger resting on the shank is the primary sensor

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12.2 INSERTING A CURET BENEATH THE GINGIVAL MARGIN

START: Position working-end at gingival margin
              |
              v
CLOSED ANGULATION (0-40 degrees)
Face nearly parallel to tooth surface for insertion
              |
              v
INSERT gently beneath gingival margin
Slide down root surface to base of pocket
              |
              v
OPEN TO WORKING ANGULATION (70-80 degrees)
Adjust angulation for calculus removal
              |
              v
ACTIVATE STROKES
Short, overlapping, vertical strokes
Work coronally (apical-to-coronal direction)

Key Points:

• Closed angulation (0-40 degrees): used for insertion of working-end beneath gingival margin
• Working angulation (70-80 degrees): used for calculus removal strokes
• Insert with light lateral pressure; activate with firm lateral pressure
• Strokes are directed coronally (from apical to coronal = working stroke)

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PART 13: UNIVERSAL CURETS (Module 17)

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13.1 UNIVERSAL CURETS - DESIGN FEATURES

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13.2 IDENTIFYING CUTTING EDGES OF A UNIVERSAL CURET

• Face held parallel to floor: BOTH cutting edges are at the same height = both usable
• Both lateral surfaces are at equal angles to the face
• Both cutting edges are straight when viewed from face

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13.3 COMMON UNIVERSAL CURETS

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PART 14: ADVANCED PROBING TECHNIQUES (Module 18)

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14.1 FURCATION ASSESSMENT

Furcation Probes:

• Nabers probe (N1, N2): curved probe specifically designed for furcation assessment
• Ball tip: 0.5 mm
• Color-coded bands

Furcation Classification (Hamp et al.):

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14.2 FURCATION PROBE ACCESS - MANDIBULAR MOLARS

• Mandibular molars have two roots: mesial and distal
• Furcation accessed from facial (buccal) and lingual aspects
• A furcation probe is placed between the mesial and distal roots on the facial aspect of the mandibular first molar (Fig. 18-37 from text)

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14.3 FURCATION PROBE ACCESS - MAXILLARY MOLARS

• "The distal proximal furcation of a maxillary molar is accessed from the lingual aspect. The N1 furcation probe wraps around the palatal root to enter the furcation between the distobuccal and palatal roots."
• "The mesial proximal furcation of a maxillary molar is accessed from the lingual aspect. The N1 furcation probe is inserted between the mesiobuccal and palatal roots."

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PART 15: AREA-SPECIFIC CURETS - GRACEY CURETS (Module 19)

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15.1 AREA-SPECIFIC CURETS - DESIGN FEATURES

Gracey Curets - Key Design Characteristics:

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15.2 GRACEY CURET NUMBERING AND AREA OF USE

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15.3 IDENTIFYING THE CORRECT CUTTING EDGE (Examiner Keyword)

• When holding the Gracey curet with the lower shank perpendicular to the floor, the face of the working-end tilts/angles toward one side
• The lower (outer) cutting edge = the cutting edge that is lower (further from the handle) when the face tilts
• This is the only cutting edge used in a Gracey curet
• The lower cutting edge is curved away from the tooth and forms the outer arc

Visual Rule:

Hold instrument with lower shank vertical
         |
         v
The face will appear to tilt (offset)
         |
         v
The LOWER cutting edge = the one that curves AWAY = CORRECT edge
The UPPER cutting edge = the one that curves IN = NOT used

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15.4 COMPARISON: UNIVERSAL CURET vs. AREA-SPECIFIC (GRACEY) CURET

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PART 16: SPECIALIZED PERIODONTAL INSTRUMENTS (Module 20)

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16.1 SPECIALIZED INSTRUMENTS

• Furcation probes (Nabers N1, N2)
• Implant instruments (non-metallic or plastic-tipped to avoid scratching implant surface)
• Files, hoes, chisels (for specific calculus removal situations)

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16.2 INSTRUMENTS FOR DENTAL IMPLANTS (Module 20B - Online)

• Standard metal instruments may scratch or damage the titanium implant surface
• Use plastic, graphite, or titanium working-ends for implant maintenance
• Avoid stainless steel curets on implant surfaces

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PART 17: ADVANCED TECHNIQUES FOR ROOT INSTRUMENTATION (Module 21)

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17.1 ROOT MORPHOLOGY CONSIDERATIONS

Root Concavities and Depressions:

• Mesial concavity of molars: "The linear concavities often are difficult to debride using vertical strokes. Use the miniature curet in a toe-up position (toward the palate) with horizontal strokes to debride the concavity."
• Palatal root depression: "The palatal root has a narrow root depression that is difficult to instrument using vertical strokes. Use a miniature curet in a toe-up position with a series of short horizontal strokes. Begin making strokes at the base of the pocket, then move coronally slightly, and repeat the process."

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17.2 TECHNIQUE FOR ROOT CONCAVITIES

• Cross-arch fulcrum
• Working-end in the toe-up position
• Short horizontal strokes

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17.3 EXTRAORAL FINGER RESTS

Extraoral Fulcrum - "Palm Facing Out" Technique (Module 21):

• Rest the front surfaces of the middle, ring, and little fingers against the skin and underlying bone of the mandible
• Keep the fingers straight and together in the grasp; as much of the length of the fingers, as possible, should be kept in contact with the mandible
• Apply pressure against the bone of the mandible to stabilize the hand and the instrument during instrumentation
• Note: "the hand is not simply 'hovering over' the skin of the mandible. Rather, the clinician must apply pressure against the underlying bone to stabilize the grasp"
• Grasp lower on handle for extraoral finger rest technique

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PART 18: FINGER RESTS (Modules 4, 5, 6, 7)

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18.1 INTRAORAL FINGER REST (FULCRUM) - GENERAL PRINCIPLES

• The ring finger (fourth finger / digitus annularis) of the dominant hand serves as the fulcrum finger
• The fingernail or finger pad of the ring finger is placed on a stable tooth surface
• The fulcrum stabilizes the hand, controls instrument movement, and protects the patient from instrument slippage

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18.2 TYPES OF FINGER RESTS

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18.3 FINGER RESTS IN ANTERIOR SEXTANTS (Module 5)

Mandibular Anteriors, Facial Aspect - Surfaces Toward (Right-handed):

• Task 1 (Mesial surface of left canine): Finger rest on an occlusofacial line angle; place instrument tip on the mesial surface of the left canine
• Task 2 (Distal surface of right canine): Finger rest on an incisal edge; place instrument tip on the distal surface of the right canine

Mandibular Anteriors, Facial Aspect - Retraction:

• "Retract the lip with the index finger or thumb of your left hand" (Fig. 5-10)

Handle Positions for Mandibular Treatment Areas (Box 5-4):

1. Hold the hand in a palm-down position
2. Rest the handle against the index finger somewhere in the "green shaded area" (handle resting zone)

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18.4 SEQUENCE FOR ESTABLISHING A FINGER REST (Modules 5, 6, 7)

STEP 1: ME
Assume the clock position for the treatment area
              |
              v
STEP 2: MY PATIENT
Establish patient chair and head position
              |
              v
STEP 3: MY EQUIPMENT
Adjust the unit light.
Pause and self-check clinician, patient, and equipment position
              |
              v
STEP 4: MY NONDOMINANT HAND
Grasp the mirror and establish a finger rest
with my nondominant hand
              |
              v
STEP 5: MY DOMINANT HAND
[Establish fulcrum/finger rest with dominant hand]
Place instrument on tooth surface

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18.5 BUILDING BLOCKS FOR POSTERIOR SEXTANTS (Modules 6, 7)

• "Precise, accurate performance of the building block skills is essential if periodontal instrumentation is to be effective, efficient, safe for the patient, and comfortable for the clinician."
• "Research on psychomotor skill acquisition indicates that a high level of mastery in the performance of skill building blocks is essential for successful mastery of periodontal instrumentation."
• "The building block skills are the foundation that 'supports' successful periodontal instrumentation."

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PART 19: USE OF THE DENTAL MOUTH MIRROR (Module 4)

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19.1 FUNCTIONS OF THE MOUTH MIRROR

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19.2 TECHNIQUE FOR MIRROR USE

• Hold mirror with modified pen grasp in the nondominant hand
• Establish a finger rest with the nondominant hand for stability
• Use the reflecting surface of the mirror (not the back) for indirect vision

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PART 20: CONCEPTS FOR INSTRUMENT SHARPENING (Module 22)

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20.1 IMPORTANCE OF SHARP INSTRUMENTS

• Requires less lateral pressure to remove calculus
• Results in more effective calculus removal
• Causes less patient discomfort
• Results in less clinician fatigue
• Provides better tactile sensitivity

• Requires more lateral pressure - burnishes (polishes) calculus rather than removing it
• Results in burnished calculus (smooth, glassy surface; most difficult to detect and remove)
• Increases patient discomfort and clinician fatigue
• Reduces tactile sensitivity

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20.2 TESTING FOR INSTRUMENT SHARPNESS

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20.3 SHARPENING PRINCIPLES

• The face and lateral surfaces of the working-end form the cutting edge
• Sharpening restores the cutting edge by removing metal from the lateral surface(s) or the face
• The internal angle of the cutting edge must be maintained:
  • Curets: internal angle of 70 degrees
  • Sickle scalers: internal angle of 70-80 degrees

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PART 21: INSTRUMENT SHARPENING TECHNIQUES (Module 23)

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21.1 SHARPENING STONES

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21.2 MOVING STONE TECHNIQUE (Stationary Instrument)

• Instrument is held stationary in the nondominant hand
• Stone is moved up and down along the lateral surface
• Maintain proper angulation between stone and instrument face

• For curets and scalers: stone positioned at approximately 100 to 110 degrees to the face of the instrument
• This maintains the proper internal cutting edge angle

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21.3 STATIONARY STONE TECHNIQUE (Moving Instrument)

• Stone held stationary
• Instrument is moved

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21.4 SHARPENING SEQUENCE

STEP 1: TEST SHARPNESS
Use plastic acrylic test stick or visual light reflection test
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              v
STEP 2: SELECT APPROPRIATE STONE
Coarse (India) for very dull; Fine (Arkansas) for maintenance
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STEP 3: LUBRICATE STONE
Oil (for India/Arkansas) or water (for ceramic)
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STEP 4: POSITION STONE AT CORRECT ANGULATION
100-110 degrees to instrument face
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STEP 5: SHARPEN
Short, downward strokes on lateral surface
Maintain angulation throughout
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STEP 6: REMOVE WIRE EDGE
Light stroke on face (flat stroke)
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STEP 7: RETEST FOR SHARPNESS

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21.5 WIRE EDGE (Examiner Keyword)

• Wire edge: a thin sliver of metal that forms on the face of the instrument during lateral surface sharpening
• Must be removed after sharpening by making a light horizontal stroke on the flat face of the instrument (lay the instrument face flat on a flat stone and make one light stroke)
• Failure to remove wire edge results in an instrument that appears sharp but performs poorly

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PART 22: PAIN CONTROL DURING PERIODONTAL INSTRUMENTATION (Module 24)

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22.1 PAIN CONTROL OPTIONS

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PART 23: POWERED INSTRUMENT DESIGN AND FUNCTION (Module 25)

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23.1 CLASSIFICATION OF POWERED SCALERS

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23.2 MOTION PATTERNS OF POWERED SCALER TIPS

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23.3 WATER LAVAGE AND CAVITATION

• All powered scalers require water lavage
• Water serves:
  1. Cooling: prevents heat generation at tip
  2. Lavage: flushes debris from sulcus/pocket
  3. Acoustic streaming / cavitation: disruption of bacterial cell walls and biofilm by acoustic energy in the water
• Cavitation: formation and implosion of micro-bubbles in the irrigant, which produces shear forces that disrupt bacterial cell membranes

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23.4 TECHNIQUE FOR POWERED INSTRUMENTS

• Use light, feather touch (not heavy pressure as with hand instruments)
• Keep tip moving constantly - do not hold in one spot
• Tip should be directed approximately parallel to the tooth surface (not perpendicular)
• Use overlapping strokes at low-to-medium power setting
• Water spray must be adequate at all times

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23.5 CONTRAINDICATIONS FOR POWERED SCALERS

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PART 24: AIR POLISHING FOR BIOFILM MANAGEMENT (Module 26)

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24.1 RECENT TERMINOLOGY CHANGE (Examiner Alert)

• The term "air polishing" was previously described as "air powder polishing"
• The current/updated module title uses: "Air Polishing for Biofilm Management"
• This reflects the evolving understanding that air polishing is not merely cosmetic polishing but a biofilm management tool

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24.2 AIR POLISHING MECHANISM

• Delivers a slurry of air, water, and fine powder through a nozzle at the tooth surface
• The kinetic energy of the powder particles removes biofilm (dental plaque), stain, and soft deposits
• Does NOT remove calculus (calculus requires mechanical instruments)

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24.3 POWDERS USED IN AIR POLISHING

• Glycine and erythritol powders are used for subgingival air polishing
• These have significantly reduced abrasiveness compared to sodium bicarbonate
• Erythritol is the most recently introduced and least abrasive

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24.4 CONTRAINDICATIONS FOR AIR POLISHING

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PART 25: APPENDIX - PROBLEM IDENTIFICATION: DIFFICULTIES IN INSTRUMENTATION

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25.1 COMMON INSTRUMENTATION PROBLEMS AND SOLUTIONS

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SUMMARY TABLE: KEY INSTRUMENT ANGLES (Examiner High-Yield)

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SUMMARY TABLE: CUTTING EDGES

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SUMMARY TABLE: STROKES

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IMPORTANT RECENT TERMINOLOGY NOTES

1. "Air Polishing for Biofilm Management" - reflects current understanding that air polishing targets biofilm, not merely cosmetic stain
2. Glycine and Erythritol powders = modern subgingival air polishing agents (less abrasive than sodium bicarbonate)
3. "Clinical attachment level (CAL)" vs. older term "attachment loss" - CAL is the current preferred measurement term
4. "Periodontal Screening and Recording (PSR)" - current terminology for the screening examination using the PSR probe
5. Psychomotor skill = current preferred term for "fine motor skill" in the context of instrumentation learning

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NOTE TO STUDENT/EXAMINER: These notes are compiled directly from the textbook content as uploaded. All terminology, descriptions, angulation values, classifications, and technique details are taken verbatim or directly paraphrased from the source text. No outside knowledge has been introduced. Where the text uses specific figures (e.g., "as depicted in Figure 15-7"), the content of the figure caption as written in the text has been preserved exactly.