PRINCIPLES OF INSTRUMENTATION

PRINCIPLES OF
INSTRUMENTATION
Presented by :
Manpreet Kaur Behl
MDS student

CONTENTS
 INTRODUCTION
 PARTS OF A PERIODONTAL INSTRUMENT
 CLASSIFICATION OF PERIODONTAL
INSTRUMENTS
 GENERAL PRINCIPLES OF
INSTRUMENTATION
 PRINCIPLES OF SCALING AND ROOT
PLANING
 INSTRUMENT SHARPENING

INTRODUCTION
PERIODONTAL
THERAPY
NON
SURGICAL SURGICAL
CHEMO -
THERAPEUTI
C
MECHANIC
AL

DEFINITION AND RATIONALE
SCALING - It is the process by which plaque and
calculus are removed from both supragingival and
subgingival tooth surfaces.
ROOT PLANING – The process by which residual
embedded calculus and portion of cementum are removed
from the roots to produce a smooth, hard, clean surface.
CURETTAGE –The scraping of the gingival wall
of a periodontal pocket to separate diseased soft tissue.

PERIODONTAL INSTRUMENTS
Designed for various purposes:
 Removing calculus
 Planing root surfaces
 Curetting the gingiva
 Removing diseased tissue.

PARTS OF AN INSTRUMENT
HANDLE SHANK
 It is that part of
instrument that is held
during activation of
working end.
 TYPES :
1.Cone socket handles
( which are separable
from shank and working
end. They permit
instrument change and
replace )
2.Fixed
 It increases the length
of instrument so that
working end can be
positioned on tooth root.
 TYPES :
1.Rigid (for heavy
calculus deposits)
2.Moderately rigid (for
fine calculus deposits
and root debridement.
3.flexible (for
subgingival calculus)

WORKING END AND ITS PARTS
( The part that does the work. It may have sharp or rounded surface. There
can be 1 or 2 working ends. )

CLASSIFICATION OF PERIODONTAL
INSTRUMENTS
These are classified according to the purpose they
serve, as follows:
1. Periodontal probes: locate, measure and mark
pockets.
2. Explorers: locate calculus deposits and caries.
3. Scaling, root planing and curettage
instruments:
 Remove plaque and calcified deposits from the
crown and root.
 Removal of altered cementum from subgingival
root surface.

4. Periodontal Endoscopes: visualize deeply into
subgingival pockets and furcations, allowing the detection
of deposits.
5. Cleansing and polishing instruments: such as rubber
cup, brushes and dental tape, used to clean and polish
tooth surfaces.
Stainless steel is most often used in instrument
manufacture. High carbon content steel instruments
are also considered to be superior.

PERIODONTAL PROBES
 Used to measure the depth of pockets and
to determine their configuration.
 Tapered, rod like calibrated in millimeters,
with a blunt rounded tip.
 Ideally, these are thin and shank is angled
to allow easy insertion into pocket.
 Furcation areas are evaluated by curved
Naber’s probe.

A, Biologic or histologic pocket depth is
the actual distance between the gingival
margin and the attached tissues (bottom
of pocket).
B, Probing or clinical pocket depth is
the depth of penetration of the probe.
PROBING
TECHNIQUE
SCIENTIFIC
SCALE

First Generation Probes
 Do not control for probing pressure and are
not suited for automatic data collection.
 These probes most commonly are used by
general dental practitioners as well as
periodontists.

Types of periodontal probes. A, Marquis color-coded probe. Calibrations are in 3-mm
sections.
B, UNC-15 probe, a 15-mm-long probe with millimeter markings at each millimeter
and color coding at the fifth, tenth, and fifteenth millimeters.
C, University of Michigan “O” probe, with Williams markings (at 1, 2, 3, 5, 7, 8, 9, and
10 mm).
D, Michigan “O” probe with markings at 3, 6, and 8 mm.
E, World Health Organization (WHO) probe, which has a 0.5-mm ball at the tip and
millimeter markings at 3.5, 8.5, and 11.5 mm and color coding from 3.5 to 5.5 mm.

WILLIAM’S PERIODONTAL
PROBE:
 The benchmark for all first generation probes.
 Invented in 1936 by Charles H.M. Williams.
 These probes are of thin stainless steel of 13 mm
in length and a blunt tip end with a diameter of 1
mm.
 The graduations on these probes are 1 mm, 2
mm, 3 mm, 5 mm, 7 mm, 8 mm, 9 mm, and 10
mm.
 The4-mm and 6-mm markings are absent to
improve visibility and avoid confusion in
reading the markings.
 The probe tips and handles are enclosed at

CPITN PROBES
 The Community Periodontal
Index of Treatment Need
(CPITN) was designed by
Professors George S. Beagrie
and Jukka Ainano in 1978.
 CPITN probes are recommended
for use when screening and
monitoring patients with the
CPITN index.
 The index & probes were first
described by WHO epidemiology,
etiology & prevention of
periodontal diseases.
 The FDI World Dental
Federation/WHO Joint Working
Group1 has advised the
manufacturers of CPITN probes
to identify as :
 CPITN-E (epidemiologic), which
have 3.5-mm and 5.5-mm
markings

 CPITN probes have
thin handles and are
lightweight (5 gm).
 The probes have a
ball tip of 0.5 mm,
with a black band
between 3.5 mm and
5.5 mm. as well as
black rings at 8.5
mm and 11.5 mm.

NABER’S PROBE
 The Naber's probe is used to detect and
measure the involvement of furcal areas
by the periodontal disease process
in multirooted teeth.
 Naber's probe also is used in the assessment of more
complex clinical cases, including those with a restorative
treatment.
 These probes can be color-coded or without
demarcation.
Exploring with a periodontal
probe (left) may not detect
furcation involvement;

SECOND GENERATION (CONSTANT PRESSURE)
PROBES
 Pressure sensitive, allowing for improved
standardization of probing pressure.
 The True Pressure Sensitive (TPS) probe
is the prototype for second-generation
probes.
 Introduced by Hunter in 1994, these probes
have a disposable probing head and a
hemispheric probe tip with a diameter of
0.5 mm.
 A controlled probing pressure of 20 gm is
usually applied. Not to exceed 0.2 N/mm sq.
 These probes have a visual guide and a
sliding scale where two indicator lines meet
at a specified pressure.

 In 1977, Armitage designed a pressure sensitive probe
holder to standardize the insertion pressure and determine
how accurate probing pressure of 25 pounds affected the
connective-tissue attachment.
 In 1978, van der Velden devised a pressure-sensitive probe
with a cylinder and piston connected to an air-pressure
system.
 Subsequently, it was modified with a displacement transducer
for electronic pocket-depth reading

 The Electronic pressure-sensitive probe, allowing for
control of insertion pressure, was introduced by Polson in
1980.
 This probe has a handpiece and a control base that allows the
examiner to control the probing pressure.
 The pressure is increased until an audio signal indicates
that the preset pressure has been reached.
 Polson’s original design was modified by its initial users.
That probe known as Yeaple probe, a modification of
Polson’s probe design which is used in studies of dentinal
hypersensitivity.

THIRD GENERATION
(AUTOMATED)
 This generation includes computer-assisted
direct data capture to reduce examiner bias and
allows for greater probe precision by :
 Standardized pressure,
 Digital readouts of probe’s readings,
 Computerized storage of data.
 These probes require computerization of the
dental operatory and can be used by
Periodontists and academic institutions for
research.

Foster-Miller probe (Foster-Miller, Inc,
Waltham, MA)
 Prototype of third-generation probes.
 Devised by Jeffcoat et al in 1986, this probe has
controlled probing pressure and automated detection
of the cementoenamel junction (CEJ).
 The components of the probe are:
 A pneumatic cylinder
 A linear variable
Differential transducer (LVDT)
 A force transducer,
 An accelerator
 A probe tip.

 Main mechanism of action of the is by detection of
the CEJ.
 The ball tip moves or glides over the root surface
at a controlled speed and preset pressure.
 Abrupt changes in the acceleration of the probe
movement (recorded on a graph) indicate when it
meets the CEJ and when it is stopped at the base of
the pocket

Advantage is the
 Automatic detection of the CEJ (which is better
landmark than gingival margin).
Disadvantage is that
 it can deem root roughness or root surface
irregularities at the CEJ.

FLORIDA PROBE
 Gibbs et al. in 1988.
 This probe consists of a
Probe handpiece and sleeve;
A displacement transducer;
A foot switch; and
A computer interface/personal computer.
 The hemispheric probe tip has a diameter of 0.45
mm, and the sleeve has a diameter of 0.97 mm .
 Constant probing pressure of 15 gm is provided by
coil springs inside the handpiece.

 They also can record missing teeth, recession,
pocket depth, bleeding, suppuration, furcation
involvement, mobility, and plaque assessment.
 Each measurement is recorded with potentially 0.2-
mm accuracy.
 Underestimation of deep probing depths,
 Lack of tactile senstivity,
 Need trained operator.

FLORIDA PASHA PROBE
 This new electronic probe has a modified sleeve, which
includes a prominent 0.125-mm edge to facilitate a
“catch” of the CEJ.
 The width of this edge is considered small enough not to
interfere with probing depth measurements, offering
clinicians measurement of CAL and probing depth
concurrently.
 This Florida PASHA Probe can reproducibly and reliably
identify the CEJ in human skulls and shows promise in
measuring CALs in humans.

TORONTO AUTOMATED
PROBE
 Devised by McCulloch and Birek in 1991 at
University of Toronto, used the occlusoincisal
surface to measure relative clinical attachment
levels.
 The sulcus is probed with a 0.5-mm nickel-
titanium wire that is extended under air
pressure.
 It controls angular discrepancies by means of
a mercury tilt sensor that limits angulation
within ± 30°.

 This probe has the advantage of an incorporated
electronic guidance system to improve precision
in probe angulation.
 It also estimates the biophysical integrity of
the dentogingival junction by measuring
intrapocket probing velocity.
 The disadvantages are associated with
positioning:
It is difficult to measure second and third molars,
and patients have to position their heads in the
same place to reproduce readings.

INTERPROBE
 Flexible probe tip, which curves with the tooth as the
probe enter the pocket area. Unlike probes that
pushes the gingiva away from tooth causing pain,
Interprobe gently slides in.
 The probe produces accurate readings of
periodontal pockets with its standardized 15 gm
of pressure.
 The probe's optical encoder handpieces uses
constant probing pressure, which provides repeatable
measurement of pocket depth and attachment loss.

FOURTH GENERATION PROBES
 These are three dimensional (3D) probes.
 These probes are aimed at recording
sequential probe positions along the gingival
sulcus.
 They are an attempt to extend linear probing in a
serial manner to take into account the continuous
and 3D pocket being examined.
 Their use can be painful.

FIFTH GENERATION PROBES
 Probes are being designed to be 3D and noninvasive: an
ultrasound or other device is added to a fourth-
generation probe.
 Fifth-generation probes aim to identify the attachment
level without penetrating it.
 The only fifth-generation probe available, the
UltraSonographic (US) probe (Visual Programs, Inc),
intoduced by Hinders & companion .
 uses ultrasound waves to detect, image, and map the
upper boundary of the periodontal ligament and its
variation over time as an indicator of the presence of
periodontal disease.

 The small intraoral probe has an ultrasound beam
projection area close enough in size to the width of the
periodontal ligament space to give the optimal
coupling and small enough to inspect the area between
the teeth, while still delivering sufficient signal strength
and depth of penetration to image the periodontal
ligament space.

EXPLORERS
 Used to locate subgingival deposits and carious
areas.
 To check the smoothness of root surfaces after root
planing.
Shepherd Hook
Explorer: for
supragingival
examination of
caries and irregular
restoration margins.
Straight
Explorer: for
supragingival
examination of
caries and
irregular
restoration
Curved
Explorer: for
calculus
detection and
shallow
pockets.
Pigtail &
Cowhorn
Explorer:
For calculus
detection and
shallow pockets.

Insertion of two types of explorers and a periodontal probe in a pocket for
calculus detection.
A, The limitations of the pigtail explorer in a deep pocket
B, Insertion of the #3 explorer.
C , Limitations of the #3 explorer. D, Insertion of the periodontal probe
TYPES OF EXPLORERS & THEIR LIMITATIONS

SCALING AND CURETTAGE
INSTRUMENTS
 Sickle scalers: heavy instruments to remove
supragingival calculus.
 Curettes: fine instruments used for subgingival
scaling, root planing and removal of soft tissue lining
the pocket.
 Hoe, chisel and file scalers: remove tenacious
subgingival calculus and altered cementum.
 Ultrasonic and sonic instruments: scaling and
cleansing tooth surfaces and curetting the soft tissue
wall of pocket.

SCALING AND CURETTAGE
INSTRUMENTS
SICKLE SCALERS (SUPRAGINGIVAL
SCALERS)
 Have flat surface and two cutting edges that converge in
a sharply pointed tip.
 Used to remove supragingival calculus.
 Used with a pull stroke.
 Scalers with straight shank: anterior teeth and
premolars.
 Scalers with contra-angle shank: posterior teeth.

 U15/30 scalers: large.
 Jacquette sickle scalers #1,2,3 : medium sized
blades.
 Curved 204 sickle scaler: large, medium or
small blades.
 Nevi 2 posterior scaler: thin enough, can be
inserted few mm subgingivally.
Fig : showing
BOTH ENDS OF U15/30
SCALER
Fig : showing Working of
A SICKLE SCALER

CURETTES
 For removing deep subgingival calculus, root
planing, altered cementum and removing soft
tissue lining the pocket.
 Each working end has cutting edge on both
sides and a rounded toe.
 Can be adapted and provide good access to
deep pockets, with minimal soft tissue trauma.
Sharper than sickle scaler.
A B
Fig – showing Working of
A CURETTE

UNIVERSAL CURETTES
 Have cutting edges that may be inserted in most
areas of dentition by altering, adapting the finger
rest, fulcrum and hand position of operator.
 Face of blade is 90-degree angle to the lower
shank.
 Blade is curved in one direction from head of the
blade to toe.
 Examples: Banhart curettes #1-2 and 5-6
Columbia curettes #13-14, 2R-2L. 4R-4L
Younger-Good #7-8
The McCall’s #17-18
Indiana University #17-18

 Offset blade: they are angled approx. 60-70
degrees from lower shank. This allows the blade to
be inserted in precise position necessary for
subgingival scaling and root planing.
 These have curved blade. (curved from head to toe
and along the side of cutting edge).
 Only pull stroke can be used.

 Available with either “rigid” or “finishing”
type of shank.
 Rigid Gracey: larger, stronger and less flexible
shank and blade than finishing Gracey.
 Rigid shank allows removal of moderate to
heavy calculus.

GRACEY CURETTES
 Designed and angled to adapt specific anatomic
areas of dentition.
 Double ended curettes paired in this manner:
 Gracey #1-2 and 3-4: Anterior teeth
 Gracey #5-6: Anterior teeth and premolars.
 Gracey #7-8 and 9-10: Posterior teeth: Facial and
lingual.
 Gracey #11-12 : Posterior teeth: Mesial
 Gracey #13-14: Posterior teeth: Distal

PRINCIPLE TYPES OF
CURETTES
GRACEY
 Designed for specific areas
& surfaces.
 One cutting edge used; work
with LOWER cutting edge only.
 Curved in two planes; blade
curves up ; to the side.
 Offset blade; face of blade
beveled at 60 degrees to
shank.
UNIVERSAL
 One curette designed for all
areas & surfaces .
 Both cutting edge used;
work with either outer /
inner edge .
 Curved in one plane; blade
curves up ; not to the side.
 Blade not offset; face of
blade beveled at 90
degrees to shank

Fig – universal & gracey
curettes seen from the toe.
Fig – universal & gracey
curettes from the blade

Gracey #15-16 : consists of Gracey #11-12 combined with more
acutely angled #13-14 shank.
Allows better adaptation to posterior mesial surfaces from a front
position with intraoral rests.
Modifications of Gracey Curettes

Gracey #17-18: modification of #13-14. has a terminal shank
elongated by 3mm and a more accentuated angulation of the
shank to provide complete occlusal clearence and better access to
all posterior distal teeth.

EXTENDED SHANK CURETTES
AFTER-FIVE CURETTES.
 Terminal shank is 3mm longer, allowing extensions
into the pockets of 5mm or more.
 Thinned blade for smoother subgingival insertion and
reduced distention.
 Large-diameter, tapered shank.
 All standard Gracey numbers except #9-10 are available
in After-Five curettes.

 Rigid After-five curettes: removal of heavy
or tenacious calculus deposits.
 Finishing After-Five curettes: for light
scaling or deplaquing in a periodontal
maintainence patient.

MINI BLADED CURETTES
 These curettes feature
blades that are half the
length of After-Five or
standard Gracey curettes.
 Shorter blade allows easier
insertion and adaptation in
deep, narrow pockets;
furcations; developmental
grooves; line angles deep
pockets.
 Can be used in areas where
root morphology or tight
tissue prevents full insertion
of other curette.

GRACEY CURVETTES
Another set of four MINI – BLADED
curettes:
Sub-0 and #1-2: anterior&
premolars.
#11-12 : posterior mesial surface.
#13-14: posterior distal surface.
Blade length is 50% shorter than
conventional Gracey curette .
Blade has been curved slightly
upward.
It has a precision balanced tip in
direct alignment with handle.

GRACEY #13-14 &
AFTER FIVE #13-14
GRACEY #5-6 &
MINI FIVE # 5-6

LANGER AND MINI-LANGER
CURETTES
 These combine the shank design of the standard
gracey #5-6, 11-12 and 13-14 curettes with a
universal blade honed at 90 degrees rather than
offset blade.

 Langer #5-6: mesial and distal surfaces of
anterior teeth.
mandibular posterior teeth.
maxillary posterior teeth.

SCHWARTZ PERIOTRIEVERS
 Set of two double-ended, highly magnetized
instruments.
 Retrieval of broken instrument tips from
periodontal pockets.
 Indispensable when clinician has a broken curette tip
in a furcation or deep pocket.
Schwartz Periotriever tip designs. The long
blade is for general use in pockets, and the
contraangled
tip is for use in furcations.

PLASTIC INSTRUMENTS FOR
IMPLANTS
 Instruments for use on titanium and other implant
abutment materials.
 Used to avoid scarring and permanent damage to
the implants.

HOE SCALERS
 Used for scaling of ledges or rings of calculus.
 The blade is bent at 99-degree angle
 Cutting edge is formed by the junction of flattened
terminal surface with the inner aspect of the blade.
 Cutting blade is beveled at 45 degrees.

 The blade is inserted to the base of the pocket so
that it makes a two point contact with the
tooth. This stabilized the instrument and
prevents the nicking of the root.
 The instrument is activated with a firm pull
stroke towards the crown, with every effort being
made to preserve the two point contact with
the tooth.
 McCall’s #3,4,5,6,7 and 8 : access to all tooth
surfaces.

FILES
 Have series of blades on a base.
 Function: to fracture or crush large deposits of tenacious
calculus or burnished sheets of calculus.
 Can easily gauge and roughen root surfaces when
used improperly.
 Not suitable for fine scaling and root planing.
 Sometimes used for removing overhanging margins of
dental restoration.
 Mini bladed curettes are currently preferred over the
files.

CHISEL SCALERS
 Double ended instrument with a curved
shank at one end and a straight shank at other end.
 The blades are slightly curved and
have a straight cutting edge
beveled at 45 degrees.
 Inserted from facial surface.
 Curve of the blade allows it to stabilize against the
proximal surface, whereas the cutting edge engages
the calculus.
 Activated by push motion.

QUETIN FURCATION CURETTES
 Actually hoes with a shallow, half moon radius that
fits into the roof or floor of furcation.
 Curvature of the tip fits into the developmental
depressions of the inner aspects of the root.
 Shanks are slightly curved for better access.
 They remove burnished calculus from recessed
areas of furcation
Quétin furcation curettes: BL2
(larger) and BL1 (smaller) tips.

DIAMOND COATED FILES
 Used for final finishing of root.
 Do not have cutting edges.
 Coated with very fine grit diamond.
 Sharply abrasive and should be used with light, even
pressure against the root surface to avoid gouging or
grooving.
 These can produce smooth, even, clean, highly
polished surfaces.

ULTRASONIC AND SONIC
INSTRUMENTS
 Used for removing plaque, scaling, curetting and
removing stain.
 Two types: MAGNETOSTRICTIVE AND
PEIZOELECTRIC
 Alternating electric current generates oscillations in
materials in the handpiece that cause the scaler tip to
vibrate.
 Vibrations range from 20,000 to 45,000 cycles per
second.

 MAGNETOSTRICTIVE UNITS: the pattern of
vibration of the tip is elliptical i.e. all the sides of tip
are active and work when adapted to the tooth.
Generate heat and require water for cooling
 PEIZOELECTRIC UNITS: the pattern of vibration is
linear, or back and forth i.e. two sides of the tips
are most active.
Do not generate heat but still utilize water for cooling
frictional heat and flushing away debris.

 Sonic Units: consists of a handpiece that
attaches to a compressed air-line and uses a
variety of specially designed tips.
 Vibrations range from 2000-6500cps, which
provides less power for calculus removal than
ultrasonic units.
 All tips are designed to operate in a wet field
with a water spray directed at the end of tip.

• Within water droplets of this spray the tiny
vaccum bubbles collape that releases energy in a
process known as CAVITATION .
• The cavitation water spray serves to flush
CALCULUS , PLAQUE , DEBRIS DISLODGED
BY VIBRATING TIP FROM THE POCKET.
• Various SCALER TIPS:

DENTAL ENDOSCOPE
 Used subgingivally for
diagnosis and treatment
of periodontal disease.
 The Perioscopy system
consists of a 0.99mm
diameter, reusable
fibreoptic endoscope
over which are fitted a
disposable, sterile sheath.
 The fibreoptic fits onto the
probes and instruments.

 The sheath delivers water irrigation that
flushes the pocket while the endoscope is being
used.
 The fibreoptic attaches to the CCD, which
produces the image.

 Allows clear visualization deeply into subgingival
pockets and furcations.
 Due to its MAGNIFICATION RANGE :-
 Permits operators to detect the presence and
location of subgingival deposits.
 Used to evaluate :
 the subgingival areas for caries,
 defective restorations,
 root fractures and resorption.

EVA system (Enhanced Visual
Assessment)
 Most efficient and least traumatic instruments.
 Correcting overhanging or overcontoured proximal
alloy and resin restorations.
 Files made of Al in the shape of a wedge protruding
form the shaft; one side of wedge is diamond coated
and other side is smooth.
 The files can be mounted on a special dental
handpiece attachment that generates
reciprocating strokes of variable frequency.

 When the unit is activated interproximally with the
diamond coated site of the file touching the
restoration and the smooth side adjacent to papilla,
the oscillating file swiftly planes the contour of
the restoration and reduces it to the desired
shape.

CLEANING AND POLISHING
INSTRUMENTS
RUBBER CUPS
 Consists of a rubber shell with or without webbed
configurations in the hollow interior. With web there are 2
types.
 Used in the handpiece with a special prophylaxis
angle.
 Currently the most common used tool for tooth polishing
is PROPHY ANGLE. It integrates a rubber cup into a
high torque gear.
 A good cleansing and polishing paste that contains
fluoride should be used and kept moist to minimize

 Avoid Aggressive use of rubber cup with any abrasive at
cervical area.
It can lead to TOOTH ABRASION &
REMOVAL OF FLUORIDE FROM ENAMEL.
 Polishing pastes like ENAMEL PRO with ACP &
NUPRO with NOVAMIN .

DENTAL TAPE
 Used for polishing proximal surfaces that are
inaccessible to other polishing instruments.
 The tape is passed interproximally while being kept at
a right angle to the long axis of the tooth and is
activated with a firm labiolingual motion.
 The area is cleansed with warm water to remove
the remnants of the paste.

AIR-POWDER POLISHING
 Prophy-Jet: introduced
first in early 1980s.
 Very effective for removal
of extrinsic stains and
soft deposits.
 Uses the slurry of warm
water and sodium
bicarbonate.
 The slurry removes
stains rapidly and
efficiently by
mechanical abrasion
and provides warm water
for rinsing and lavage.

Disadvantages:
 Abrasion of tooth structure
 The active ingredient makes loss of dentin & cementum.
 Roughening of amalgam, composite resins, cements and
nonmetallic restorations.
Contraindications
 patients with history of respiratory illness and hemodialysis.
 Hypertensive patients on sodium restricted diet or patients
on medications affecting electrolyte balance.
 Patients with infectious disease.

GENERAL PRINCIPLES OF
INSTRUMENTATION
1. Accessibility:
Positioning of
Patient and Operator
 Facilitates
thoroughness of
instrumentation.
 Inadequte
accessibility impedes
the instrumentation,
tires the operator,
diminishes his or her
effectiveness.
 Clinician’s feet flat
and thighs parallel
to floor.
 Straight back and
head erect.

RIGHT-HANDED CLINICIAN LEFT-HANDED CLINICIAN
• 7 o’ clock position to the • 5 o’ clock position, to the
front of the patient’s head. front of the patient’s head.
• 9 o’ clock position to the • 3 o’ clock position, to the
side of the patient’s head. side of the patient’s head.
• 10 to 11 o’ clock, to the • 2 to 1 o’ clock position,
back of the patient’s head. to the back of the patient’s head.
• 12 o’ clock position, directly • 12 o’ clock position, directly
directly behind the patient’s head. behind the patient’s head.

2. Visibility, Illumination and Retraction
 Direct vision with
direct illumination
from dental light is most
desirable.
 Indirect vision
obtained by using
mouth mirror.
 Indirect illumination by
using retraction of
cheeks or tongue; index
finger used for
retraction of lips or
cheeks.

FOLLOWING METHODS EFFECTIVE FOR
RETRACTION:
Retraction of cheek using mouth mirror Retraction of lower lip using index fing
Retraction of tongue using mouth mirro

Fig – THE FOCUSING OF DENTAL CHAIR
LIGHT

3. Condition and Sharpness of
Instruments
 Should be clean, sterile and in good
condition.
 Working ends must be sharp.
 Dull instruments lead to incomplete calculus
removal and trauma.
 Advantages
- Easy removal.
- Improved stroke control and reduced number of
strokes.
- Reduced clinician fatigue and increased patient
comfort.

4. Maintaining a Clean Field
 Pooling of saliva interferes with visibility and impedes
control.
 A firm finger rest could not be established.
 Adequate suction is essential.
• Blood and debris can be removed from the operative field
with suction and by wiping or blotting with gauze
squares.
• The operative field should also be flushed occasionally with
water.
• Compressed air and gauze square can be used to
facilitate visual inspection of tooth surfaces just below the
gingival margin during instrumentation.
• Retractable tissue can also be deflected away from the
tooth by gently packing the edge of gauze square into the

5. Instrumental Stabilization
INSTRUMENT GRASP
 Most effective is : MODIFIED PEN GRASP

The thumb, index and middle finger are used to
hold the instrument, but the middle finger is positioned
so that the pad next to the fingernail is resting on the
instrument shank.
 The index finger is bent on the second joint and
positioned well above the middle finger on same side
of handle.
 Pad of thumb placed midway between the middle
and index finger on opposite side of handle, hence
creates the ‘tripod effect’.

PALM AND THUMB GRASP
 Useful for stabilizing
instruments during
sharpening.
 Manipulating air and
water syringes, but it is
not recommended for
periodontal
instrumentation.
 Manoeuvrability and
tactile sensitivity are so
inhibited by this grasp
that it is unsuitable for the
precise, controlled
movements necessary
during periodontal
procedures.

 The fourth finger is preferred for finger rest.
 Although it is possible to use third finger, but it is not
recommended as it restricts the arc of movement
during the activation of strokes.
 Maximal control is achieved when middle finger is
kept between shank and fourth finger.
 Hence these two fingers are used as a one-unit
fulcrum during scaling.

INTRAORAL FINGER REST
CONVENTIONAL :
The fourth finger rests on the
occlusal surfaces of adjacent
teeth.
CROSS-ARCH:
incisal surfaces of teeth on the
opposite side of the same arch.

OPPOSITE –ARCH :
mandibular teeth while the
maxillary posterior teeth are
instrumented.
FINGER ON FINGER:
The fourth finger rests on
index finger of the non
operating hand.

EXTRAORAL FINGER REST
 Allow optimal access and angulation while providing adequate
stabilization.
 Extraoral fulcrums are not “finger rests” in the literal sense, because
the tips or pads of the fingers are not used for extraoral fulcrums
as they are for intraoral finger rests.
PALM-UP:
Backs of the fingers rest on the right
lateral aspect of the mandible while the
maxillary right posterior teeth are
instrumented.
PALM-DOWN:
The front surfaces of finger rests on the
mandible while maxillary left posterior teeth
are instrumented.

INDEX-FINGER
REINFORCED REST:
The index finger is placed
on the shank for pressure
and control in maxillary
left posterior lingual
region.
THUMB-REINFORCED
REST:
The thumb is placed on the
handle for control in the
maxillary right posterior
lingual region.

6. INSTRUMENT ACTIVATION
 ADAPTATION
Refers to the manner in which the working end of an
instrument is placed against the surface of a tooth.

The tip and side of the probe should be flush
against the tooth surface as vertical strokes
are activated within the crevice.
The lower third of the working end must be
kept in constant contact with the tooth
while it is moving over varying tooth
contours.

 If only the middle third of the working end is adapted
on a convex surface so that the blade contacts the
tooth at a tangent, the toe or sharp tip will jut out
into soft tissue, causing trauma and discomfort.
 If it is adapted so that only the toe or tip is in
contact , the soft tissue can be distended or
compressed by the back of the working end, also
causing trauma and discomfort.

INSTRUMENT ANGULATION
 It refers to the angle between the face of bladed
instrument and tooth surface.
 Also called tooth-blade relationship.

Blade angulation. A, 0 degrees: correct angulation for blade insertion.
B, 45 to 90 degrees: correct angulation for scaling and root planing.
C, Less than 45 degrees: incorrect angulation for scaling and root
planing.
D, More than 90 degrees: incorrect angulation for scaling and root
planing, correct angulation for gingival curettage.

Angulation less than 45 degrees, the
cutting edge will slide over the calculus,
smoothening or burnishing it.
Angulation more than 90 degrees, lateral
surface will be against the tooth and
calculus will be burnished
Angulation should be just
less than 90 degrees so that
cutting edge bites into
calculus.

LATERAL PRESSURE
 Refers to the pressure created when force is
applied against the surface of a tooth with the
cutting edge of a bladed instrument.
 May be firm, moderate or light.

STROKES
Three Basic strokes used:
 Exploratory Stroke
 Scaling Stroke
 Root planing Stroke
 Any of these strokes are activated in a vertical,
horizontal or oblique direction.

EXPLORATORY STROKE
Light feeling stroke used with probes or explorers
 Evaluate the dimension of the pocket
 To detect calculus and irregularities of the tooth
surface.
 Grasped lightly and adapted with light pressure to
achieve maximal tactile sensitivity.

SCALING STROKE
 Short, powerful pull
stroke.
 Removal of supragingival
and subgingival calculus.
 The cutting edge
engages the apical
border of calculus and
dislodges it with a firm
movement in coronal
direction.
 Finger flexing is
indicated for precise
control over stroke in line
angles and lingual or
facial aspects of narrow

ROOT PLANING STROKE
 Moderate to light pull
stroke.
 Used for final
smoothening and
planing of root surface.
 Curette is adapted to the
tooth surface with even,
lateral pressure.
 A continuous series of
long, overlapping
shaving strokes is

PRINCIPLES OF SCALING AND ROOT
PLANING
DETECTION SKILLS
Visual examination
 Compressed air may be used to dry supragingival
calculus until it is chalky white and readily visible.
 Air also may be directed into the pocket in a steady
stream to deflect the marginal gingiva away from the
tooth so that subgingival deposits near the surface
can be seen.

Tactile exploration
 The explorer or probe is
held with a light but
stable modified pen
grasp.
 When calculus is
encountered, the tip of
the instrument should be
advanced apically over
the deposit until the
termination of the
calculus on the root is

 The distance between the apical edge of the calculus
and the bottom of the pocket usually ranges from 0.2
to 1.0 mm.
 The tip is adapted closely to the tooth to ensure the
greatest degree of tactile sensitivity and avoid tissue
trauma.
 When a proximal surface is being explored, strokes
must be extended at least halfway across that surface
past the contact area to ensure complete detection of
inter-proximal deposits.
 When an explorer is used at line angles, convexities,
and concavities, the handle of the instrument must be
rolled slightly between the thumb and fingers to keep
the tip constantly adapted to the changes in tooth
contour.

SUPRAGINGIVAL SCALING
TECHNIQUE
 Sickles, curettes, and ultrasonic and sonic
instruments are most often used for the removal of
supragingival calculus; hoes and chisels are less
frequently used.
 The sickle or curette is held with a modified pen
grasp, and a firm finger rest is established on the
teeth adjacent to the working area.

 The blade is adapted with an angulation of
slightly less than 90 degrees to the surface
being scaled.
 The cutting edge should engage the apical
margin of the supragingival calculus while short,
powerful, overlapping scaling strokes are
activated coronally in a vertical or an oblique
direction.

The tooth surface is instrumented until it is
visually and tactilely free of all supragingival
deposits.

SUBGINGIVAL SCALING AND ROOT
PLANING
 The curette is preferred by most clinicians for
subgingival scaling and root planing because of the
advantages afforded by its design.
 Its curved blade, rounded toe, and curved back
allow the curette to be inserted to the base of the
pocket and adapted to variations in tooth contour with
minimal tissue displacement and trauma.

 The curette is held with a
modified pen grasp, and a
stable finger rest is
established.
 The correct cutting edge is
slightly adapted to the
tooth, with the lower
shank kept parallel to the
tooth surface.
 The blade is then inserted
under the gingiva and
advanced to the base of
the pocket by a light

 When the cutting edge
reaches the base of the
pocket, a working
angulation of between 45
and 90 degrees is
established, and
pressure is applied
laterally against the
tooth surface.
 Calculus is removed by a
series of controlled,
overlapping, short,
powerful strokes
primarily using wrist-
arm motion.
SUBGINGIVAL SCALING PROCEDURE.
A Curette inserted with the face of the blade
flush against the tooth.
B Working angulation (45-90 degrees) is
established at the base of the pocket.
C Lateral pressure is applied, and the scaling
stroke is activated in the coronal direction.

 Longer, lighter root-planing strokes are then
activated with less lateral pressure until the root
surface is completely smooth and hard.
 The instrument handle must be rolled carefully
between the thumb and fingers to keep the blade
adapted closely to the tooth surface as line angles,
developmental depressions, and other changes in
tooth contour are followed.

 The amount of lateral pressure applied to the tooth
surface depends on the nature of the calculus and
whether the strokes are for initial calculus removal or
final root planing.
 If heavy lateral pressure is continued after the bulk of
calculus has been removed and the blade is
repeatedly readapted with short, choppy strokes,
the result will be a root surface roughened by
numerous nicks and gouges, resembling the
rippled surface of a washboard.
 If heavy lateral pressure is continued with long, even
strokes, the result will be excessive removal of root
structure, producing a smooth but “ditched” or
“riffled” root surface.

INSTRUMENTATION IN PROXIMAL
SURFACES
 A common error in is failing to reach the midproximal
region apical to the contact.
 This area is relatively inaccessible, and the technique
requires more skill than instrumentation of buccal or
lingual surfaces.
 With properly designed curettes, this can be
accomplished by keeping the lower shank of the
curette parallel with the long axis of the tooth.
 The blade of the curette will reach the base of the
pocket and the toe will extend beyond the midline
as strokes are advanced across the proximal
surface.

 If the lower shank is angled or tilted away from the
tooth, the toe will move toward the contact area.
 Because this prevents the blade from reaching the
base of the pocket, calculus apical to the contact will
not be detected or removed.
A, Correct shank position, parallel with
the long
axis of the tooth. B, Incorrect shank
position, tilted away from the tooth. C,
Incorrect shank
position, tilted too far toward the tooth.

Maxillary right posterior sextant: facial aspect.Maxillary right posterior sextant,
premolar region only: facial aspect
Maxillary right posterior sextant: lingual
aspect.
Maxillary anterior sextant: facial aspec

Maxillary anterior sextant: lingual aspect Maxillary left posterior sextant: facial as
Maxillary left posterior sextant: facial aspect.Maxillary left posterior sextant: lingual a

Mandibular left posterior sextant: facial
aspect.
Mandibular left posterior sextant:
lingual aspect.
Mandibular anterior sextant: facial aspect Mandibular anterior sextant: lingual asp

Mandibular right posterior sextant:
facial aspect.
Mandibular right posterior sextant: lingua
aspect.

SHARPENING OF
INSTRUMENTS
 With use against the
tooth surface, the metal
is worn away from the
cutting edge until it
becomes a rounded
surface instead of a
fine line.
 A dull cutting edge is
a rounded junction
between the face and
lateral surface of
instrument.

EVALUATING SHARPNESS
 Visual Examination
 A dull cutting egde reflects
light as it is rounded and
thick, whereas sharp edge
doesn’t.
 Tactile Examination
 Use of a sharpness stick
test.
 A dull cutting egde slides
over the surface of the
stick while the sharp egde
scratches the stick

SHARPENING STONES
MOUNTED STONES
 Mounted on a metal mandrel and used in a motor-driven
handpiece.
 They may be cylindrical, conical, or disc shaped.
 These stones are generally not recommended for
routine use because they
(1) are difficult to control precisely and can ruin the
shape of the instrument,
(2) Tend to wear down the instrument quickly, and
(3) can generate considerable frictional heat, which may
affect the temper of the instrument.

UNMOUNTED STONES
 Some are rectangular
with flat or grooved
surfaces, whereas others
are cylindrical or cone
shaped.
 Unmounted stones may
be used in two ways: the
instrument may be
stabilized and held
stationary while the
stone is drawn across it,
or the stone may be
stabilized and held
stationary while the
Top to bottom, A flat India stone, a flat
Arkansas stone, a cone-shaped
Arkansas stone, and a ceramic stone.

PRINCIPLES OF SHARPENING
 Choose an appropriate stone.
 Sterilization of the stone.
 Establish the proper angle between the stone and
surface of the instrument.
The stone makes a 100- to 110-degree
angle with the face of the blade.
The stone meets the blade at an
angle of 100 to 110 degrees.

When the entire bevel on a chisel
contacts the sharpening stone, the
angle between the
instrument and the stone is 45 degrees.
Back-action chisels and hoes are
sharpened with a pull stroke.
As with the curette, the sickle has an
angle of 70 to 80 degrees between the
face of the blade and the lateral surface.

 Avoid heavy pressure as it may lead to quick
grinding of the surface by the stone.
 Avoid the formation of a “wire edge,” characterized
by minute filamentous projections of metal extending
as a roughened ledge from the sharpened cutting
edge.
 A wire edge is produced when the direction of the
sharpening stroke is away from, rather than into or
toward, the cutting edge.
 Lubricate the stone during sharpening. This
minimizes clogging of the abrasive surface of the
sharpening stone with metal particles removed from
the instrument.

ULTRASONIC AND SONIC
INSTRUMENTATION

Mechanism of Action
 Various physical factors play a role in the
mechanism:
FREQUENCY
 Number of times per second an insert tip moves
back and forth during one cycle in an orbital,
elliptical or linear stroke path.
 Determines the area of the insert tip that is
considered active.
 Higher frequency results in a smaller active area of an
insert tip.

STROKE
 It is the maximum distance an insert tip travels
during one cycle or stroke path.
 Amplitude is equal to one-half the distance of the
stroke.
 High power settings produce a longer stroke
pattern and vice versa.

WATER FLOW
 Water contributes to the three physiological effects
that enhance the efficacy of scalers:
 Acoustic Streaming: unidirectional fluid flow caused
by ultrasound waves.
 Acoustic turbulence: created when the movement of
the tip causes the coolant to accelerate, produces an
intensified swirling effect.
 Cavitation: formation of the bubbles in the water
caused by high turbulence. The bubbles implode and
produce shock waves in the liquid.

Types of POWERED
INSTRUMENTS
SONIC SCALERS
 Air-driven scalers in which
frequency produces a
vibration of the insert tip.
 Use a high-speed or low
speed air source from the
dental unit.
 Tips are large in diameter
and universal in design.
 Elliptical to orbital stroke
pattern, which allows the
tip to adapt to all tooth
surfaces.

ULTRASONIC SCALERS
PEIZOELECTRIC:
 Ceramic discs located in the handpiece.
 Can change the dimension as electric energy is
applied to the tip.
 Move in a linear pattern
 Two active surfaces of the tip.

MAGNETOSTRICTIVE
 Metal stacks that change dimension when
electrical energy is applied power magnetostrictive
technology.
 Vibrations travel from the metal stack to a connecting
body, causing the vibration of the tip.
 Elliptical or orbital stroke pattern.
 Four active working surfaces.

EFFICACY AND CLINICAL
OUTCOMES
1. Plaque and Calculus Removal
 Remove heavy subgingival calculus deposits.
 Both deplaquing of root surfaces and
subgingival scaling may be accomplished.

 Clifford et al. found that both traditional ultrasonic and
microultrasonic inserts were effective in disrupting the apical
plaque border.
 Gagnot et al.found that ultrasonic miniinserts were more
effective in the apical plaque zone than curettes.
 Garnick and Dent showed that both hand and ultrasonic
instrumentation removed plaque equally well.
 Busslinger et al. found that hand and ultrasonic
instrumentation with either a magnetostrictive or a piezoelectric
insert were equally effective in calculus removal.
 Patterson et al. found sonic and ultrasonic scalers removed
similar amounts of calculus.

2. Bacterial reduction and cementum
removal
 Ultrasonic instruments using high-speed action produce
cavitational activity and acoustic microstreaming that may
facilitate the disruption of the bacteria in subgingival
biofilms.
 Some in vitro studies have shown that cavitational activity
and acoustic microstreaming may enhance cleaning efficacy
and increase plaque reduction.
 O’Leary et al. found that up to 5 minutes of ultrasonic
activation resulted in significant killing of Actinobacillus
actinomycetemcomitans and Porphyromonas gingivalis.
However, the investigators acknowledged that increased
temperature caused by “sonication” may have contributed to
the reduction.

 Leon and Vogel, found that ultrasonic
instrumentation in class II and class III furcations was
more effective in reducing bacteria and keeping
bacterial at a healthy level longer than hand
instrumentation.
 Renvert et al. demonstrated that neither root
debridement with ultrasonic scaling nor osseous flap
surgery eliminated A. actinomycetemcomitans.
 Oosterwaal et al. studied subgingival plaque
samples after scaling using ultrasonic or hand
instruments and found that both reduced subgingival
microbiota to a level consistent with periodontal
health.

3. Furcation Access
 Leon et al. demonstrated that ultrasonic scalers were
equal to hand scalers in reducing the bacteria in class I
furcations but more effective in class II and III
furcations.
 Sugaya et al. found that an ultrasonic tip specifically
designed for furcations was more effective in debriding
either class II furcations or furcations with a horizontal
probing depth greater than 2 mm.
 Patterson et al. found that both ultrasonic and sonic
tips were similar in their ability to remove calculus in
furcations.

4. Reduced Time
 Reduce the amount of time needed for scaling and
root planing, a benefit for both the practitioner and the
patient.
 Copulos et al. found that instrumentation time per
tooth with an ultrasonic scaler was 3.9 minutes versus
5.9 minutes for hand instruments.
 Kocher and Plagmann found that a diamond-coated
sonic scaler used to debride furcations during flap
surgery reduced treatment time by 50% over hand
instrumentation.

Disadvantages
1. Aerosol Production
 Barnes et al. demonstrated that the aerosol produced
by the in vivo use of an ultrasonic scaler on
periodontally involved teeth was contaminated with
blood and that the contamination occurred regardless
of the level of inflammation.
 Rivera-Hidalgo et al. compared focused-spray and
standard-spray ultrasonic inserts and found that each
produced an equal amount of aerosol contamination.

 Harrel and Molinari recommend three levels of defense
in the reduction of dental aerosols:
(1) personal protective barriers, such as a mask, gloves,
and safety glasses;
(2) routine use of a preprocedural antiseptic rinse; and
(3) use of a highspeed evacuation device by a dental
assistant or attached to the instrument being used.
High-speed evacuation, aerosol reduction devices
attached to the ultrasonic scaler, and antiseptic
rinsing have all been shown to reduce aerosol
contamination.2. Patients with cardiac pacemakers
 Miller et al. found atrial and ventricular pacing was
inhibited by electromagnetic interference produced by a
magnetostrictive ultrasonic scaler.
 A sonic scaler was also tested but did not produce the
same effect.

PRINCIPLES :
 A modified pen grasp is used with an ultrasonic scaler,
together with an extraoral fulcrum.
 The extraoral fulcrum allows the operator to maintain a
light grasp and easier access physically and visually to
the oral cavity.
 Alternate fulcrums using cross-arch or opposite-arch
finger rests are acceptable alternatives.
 Light pressure is needed with a power instrument. The
tip is traveling at a set frequency in a set stroke pattern.
Increased pressure by the clinician on the tip causes
decreased clinical efficacy.

 Sonic/ultrasonic instrumentation requires removal from
the coronal to the apical portion of the deposit.
 This stroke pattern allows the insert to work at its optimal
stroke pattern and frequency for quick, effective
removal of deposits.
 A deplaquing stroke should be used when the focus is
removal of biofilm and soft debris for the resolution of
gingival inflammation.
 This stroke entails accessing every square millimeter
of the tooth surface during ultrasonic deplaquing
because of the limited lateral dispersion of the lavage

ACTIVE TIP AREA
 Portion of instrument tip that is capable of doing
work.
 It is the vibration energy of a powered
instrument tip that is responsible for calculus
removal.
 Active tip area ranges from 2 to 4 mm of
length of the instrument tip.
 Higher the frequency of instrument, shorter
the active tip area.

Adaptation
 Point of Tip: should never be adapted on the tooth
surface. The high energy output could damage the
tooth.
 Face of Tip: Should not be adapted to tooth surface due
to high energy output.
 Back of Tip: Most effective in debridement in
magnetostrictive units. The back can be adapted to tooth
surfaces.
 Lateral Surfaces of Tip: Adaptation is recommended
with all sonic, peizoelectric and magnetostrictive units.

 The tip is kept in constant contact to the tooth.
 Calculus removal: gentle tapping motion.
 Subgingival deplaquing: gentle sweeping motion.

INSTRUMENT TIP WEAR AND
REPLACEMENT
 A rule of thumb is that 1mm of wear results in
approximately 25% of the tip wear.
 Approx. 50% loss of efficiency occurs at 2mm
of wear and tip should be discarded at this
point.

PRINCIPLES OF INSTRUMENTATION

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