The document outlines principles of instrumentation in periodontal procedures, including positioning of the operator and patient, maintaining visibility through retraction and illumination, proper instrument handling techniques like grasping and finger rests, and factors such as instrument activation and maintaining a clean field. Key points covered are appropriate chair and body positions, methods of retraction, grasps for instrument control, and techniques to optimize visibility and access in the oral cavity.

1. GENERAL PRINCIPLE OF INSTRUMENTATION

2. LEARNING OBJECTIVES
• Accessibility
• Visibility, illumination and retraction
• Condition of instruments
• Maintaining of clean field
• Instrument stabilization
• Instrument activation
• Instrument stroke
• Scaling and root planing

3. ACCESSIBILITY
Position of operator
The clinician should be seated on a comfortable
operating stool that has been positioned so that-
• Head is relatively erect. Head in the least strained
position vertically and horizontally.
• Eyes are directed downward in a manner that
prevents head and neck strain.
• Distance from patients mouth to the eyes of clinician
should be 14-16 inches.

4. • Shoulders are relaxed.
• Fore arm and wrist are kept in straight line, wrist is neither
flexed nor extended.
• Body weight is completely supported by chair.
•Back is straight and erect.
•Thighs should parallel with floor.
• Feet should flat on the floor.

5. The patient’s chin is at 6 ‘O’ clock. The
right handed clinician sits between 9
and 12 ‘O’ clock. The left handed
clinician sits on opposite side between
12 to 3 ‘O’ clock.

6. Position of the patient
For maxillary arch-
The patient should be asked to raise the chin slightly to
provide visibility and accessibility.
For mandibular arch-
It may be necessary to raise the back of chair slightly and
request that the patient lower the chin untill the mandible
is parallel to the floor.

7. Assistant is seated with eye level 4-6 inches above the
clinician’s eye level and facing towards the head of the dental
chair.

8. The various positions of the patients on the
dental chair-
Upright – initial position from which chair position are made.
Semiupright- respiratory and cardiovascular patients.
Supine- flat position with head and feet are on the same position.
Trendlenburg- modified supine position when the head is lower
than the heart. The brain is lower than heart and feet slightly
elevated.

9. VISIBILITY, ILLUMINATION AND RETRACTION
• Direct vision and direct illumination from dental light is most
desirable.
• If this is not possible, indirect vision may be obtained by using
mouth mirror and indirect illumination may be obtained by
using the mirror to reflect the light to where it is needed.
• Indirect vision and indirect illumination are often used
simultaneously.

10. • Retraction provides visibility, accessibility and illumination.
• Fingers and/or mirrors are used for retraction.
EFFECTIVE METHODS FOR RETRACTION
• Use the mirror to deflect the cheek, while the fingers of non
operating hand retract the lips and protect the angle of mouth
from irritation.
• Use the mirror alone to retract the lips and cheek.
• Use the finger of non operating hand to retract the lips.
• Use mirror to retract the tongue.
• Combination of the preceding methods.

11. Direct vision and direct illumination Indirect vision and indirect illumination
Direct vision and direct illumination in
the mandibular left
premolar area.
Direct vision and direct illumination
in the mandibular left premolar
area.

12. Indirect illumination
Direct vision and direct illumination in
the mandibular left premolar area.

13. Retraction by index finger
Retraction by mouth mirror

14. • While retracting care should be taken to avoid irritation to the
angle of the mouth. If the lips and skin are dry, softening the
lips with petroleum jelly before instrumentation is helpful
precaution against cracking and bleeding.
• Careful retraction is especially important for a patient with
history of recurrent Herpes Labialis because these patient
may easily develop herpatic lesions after instrumentation.

15. CONDITION AND SHARPNESS OF INSTRUMENT
Steps in the effective care of instrument
• Instruments are cleaned after each use by removing blood
and debris under running water.
• The instruments are sharpen regularly and sharpness is
checked thereafter.
• Instruments are sterilized thoroughly.

16. MAINTAINING CLEAN FIELD
• Operating field is obscured by saliva, blood and debris.
To avoid
Adequate suction is essential and can be achieved with
saliva ejector, aspirator or suction.

17. • Blood and debris can be removed by suction or by wiping or
blotting with gauze piece.
• Compressed air and gauze squares can be used to facilitate
visual inspection of tooth surfaces just below gingival margin.

18. INSTRUMENT STABILIZATION
• Stability of the instrument and the hand is the primary
requirement for controlled instrumentation.
• Stability and control are essential for effective instrumentation
and avoidance of injury to the patient or clinician.
• The two factors of major importance in providing stability are
the instrument grasp and the finger rest.
• Instrument Grasp A proper grasp is essential for precise control of
movements made during periodontal instrumentation.
• The most effective and stable grasp for all periodontal instruments
is the modified pen grasp.
• Although other grasps are possible, this modification of the
standard pen grasp. ensures the greatest control in performing
intraoral procedures.

19. Instruments Techniques (Grasping)
Modified pen grasp: greatest touch delicacy is permitted with
this grasp. A pad of thumb, index and middle fingers contacting the
instrument. While tip of ring and/or little fingers is used for rest or
support on the nearby teeth surface of the same arch for better
controlling the action and the magnitude of force applied. Palm is
usually facing away from the operator.
Inverted pen grasp: same as modified pen grasp except that the
hand is rotated so that palm is facing more toward operator. Usually
used with lingual surfaces of anterior teeth.

20. Palm and thumb grasp: similar to that used
for holding a knife while paring the skin from
an apple. Rest is provided by supporting the
thumb on nearby teeth. Used for preparing
incisal retention in class III cavities.
Modified palm and thumb grasp: only
used when its feasible to rest the thumb on
the tooth to be prepared or the adjacent
tooth.

24. FINGER RESTS
• Finger rests may be generally classified as intraoral finger rests or
extraoral fulcrums.
• Intraoral finger rests on tooth surfaces ideally are established close to
the working area.
• Variations of intraoral finger rests and extraoral fulcrums are used
whenever good angulation and a sufficient arc of movement cannot
be achieved by a finger rest close to the working area. The following
examples illustrate variations of the intraoral finger rest:
• 1. Conventional: The finger rest is established on tooth surfaces
immediately adjacent to the working area .
• 2. Cross-arch: The finger rest is established on tooth surfaces on the
other side of the same arch .
• 3. Opposite arch: The finger rest is established on tooth surfaces on
the opposite arch (e.g., mandibular arch finger rest for
instrumentation on the maxillary arch) .
• 4. Finger on finger: The finger rest is established on the index finger
or thumb of the nonoperating hand

27. INSTRUMENT ACTIVATION

32. THANK YOU

33. Q.1. Aerosols are produced by:
(A) magnetostrictive scaler
(B) Sonic scaler
(C) peizo electric scaler
(D) all of the above

34. • Q.2. Chair position in pregnant patient:
(a) supine
(b) Semisupine
(c) Trendelenberg
(d) Left lateral

35. Q.3. Most common used finger for retraction is:
(a) Thumb
(b) middle finger
(c) Index finger
(d) Ring finger

36. Q.4. in which trimester of pregnancy the periodontal treatment
is considered to be safe:
(a) first
(b) second
(c) third
(d) in any of trimester

37. Q.5. The distance from patients mouth to the eyes of the
clinician:
(a) 12-14 inches
(b) 14-16 inches
(c) 16-18 inches
(d) 18-20 inches