1. Patient and operator positions

2. CONTENTs HISTORY INTRODUCTION DENTAL CHAIR AND PATIENT POSTIONS
OPERATOR POSITIONS
OPERATING STOOLS
GENERAL CONSIDERATIONS .

3. HISTORY
1790 was a big year for dentistry, as this was also the year the first specialized dental chair was invented.
It was made from a wooden chair with a headrest attached.

4. INTRODUCTION
Until a few decades ago , most dental procedures were performed with patient seated upright and dentist standing next to patient ,this prolonged period caused musculoskeletal disorders for dentists.

5. Dental chair and patient position
Modern dental chairs are designed to provide total body support in any chair position.
The patient head is supported by a head rest cushion which elevates the chin and thus reducing strain on neck
A patient who is in a comfortable position is more relaxed, has less muscular tension and is more capable of cooperating with the dentist.

6. The choice of patient position varies with the operator, the type of procedure, and the area of the mouth involved in the operation.
For operative dental procedures , the patient may be seated in one of the following positions:
Upright position
Almost supine
Reclined 45 degrees

7. UPRIGHT POSITION
This is the initial position of chair from which further adjustments are made

8. ALMOST SUPINE POSITION:
In this position the chair is tilted so that the patient is almost in a lying down posture
The patient’s head ,knees and feet are approximately at the same level
Patient’s head should not be lower than feet except in case of syncopal attack

9. 2. RECLINED 45 DEGREE POSITION:
In this position the chair is reclined at 45 degrees so that when the patient is seated, the mandibular occlusal surfaces are almost at 45 degrees to the floor
Once the treatment is over the chair is brought back to upright position so that the patient can leave the chair easily

10. Operator position:
 Once the patient has been comfortably positioned, the dentist and the assistant should sit themselves in the proper positions for treatment.
Correct positioning of the operator is very important to have good visibility and accessibility to oral cavity.

11. Operator position:
Usually sitting position is preferred in modern dentistry to relieve stress on operator's leg and support the operator's back.

12. Operator position
The level of teeth being treated should be placed at same level as the level of operator's elbow.
Forearm parallel to the floor
Thighs parallel to the floor
Hip angle of 90 degrees
Seat height positioned low enough so that the heels of your feet touch the floor

13. When working from clock positions 9-12:00, feet spread apart so that your legs and the chair base form a tripod which creates a stable position
Back of the operator should be always straight
Head erect and should not be bent of drooping

14. FOR A RIGHT HANDED OPERATOR:
OPERATING POSITIONS
Right front or 7’o clock position
Right or 9’o clock position
Right rear or 11’o clock position
Direct rear or 12’oclock position
LEFT HANDED OPERATOR'S POSITIONS ,
5 o'clock, 3 o'clock and 1 o'clock .

15. RIGHT HANDED OPERATOR—
3 PREFERRED POSITIONS
LEFT HANDED OPERATOR—
7 O’CLOCK
5 O’CLOCK
9 O’CLOCK
3 O’CLOCK
11 O’CLOCK
1 O’CLOCK

16. RIGHT FRONT OR 7’O CLOCK POSITION
This is convenient for examination and working on the
Mandibular anterior teeth
Mandibular right posterior teeth
Maxillary anterior teeth
TO INCREASE THE EASE AND VISIBILITY, THE PATIENT'S HEAD MAY BE TURNED TOWARDS THE OPERATOR.

17. RIGHT OR 9’O CLOCK POSITION
The operator is directly to the right of the patients.
The position is convenient for operating on the
Facial surface of the maxillary & mandibular right posterior teeth
Occlusal surface on mandibular right posterior teeth .

18. RIGHT REAR OR 11’O CLOCK POSITION
Position of choice for most operations.
Most areas of mouth are accessible and can be viewed directly or indirectly using a mouth mirror.
The dentist sits to the right and slightly behind the patient and the left arm is positioned around the patient’s head
WORKING AREAS INCLUDE:
Palatal and incisal surfaces of maxillary teeth (indirect vision)
Mandibular teeth, particularly on the left side (direct vision).

19. DIRECT REAR OR 12’OCLOCK POSITION
Here the dentist sits directly behind the patient and looks down over the patient’s head
This position is mainly used only for working on lingual surfaces of mandibular and maxillary anterior teeth.

20. Operator stools: The design of the stool is important.
It should be sturdy and well balanced to prevent tipping/gliding away from dental chair
It should be well padded with cushion edges and should be adjusted up and down
A well designed stool increases operator comfort and reduces fatigue

21. LIGHTING;
The operator should be well illuminated either by natural or artificial light.
If the light is kept too close , it impairs the physical movement of operator & also increases patient discomfort due to heat production.
If the light is kept far away, it reduces the illumination.
As a rule for mandibular arch the light is kept in a higher position & for maxillary arch it is kept in a lower position.

22. General Considerations:
The patient’s head should be rotated according to need of operator without hesitation
During working maxillary occlusal surfaces should be perpendicular to the floor and for mandibular occlusal surface should be 45 degrees
The operator should maintain space between the patient as while reading a book

23. There should be reduced contact with patient
The operator should never rest his hand on patient’s face
The chest of patient should never be used as trays to keep instruments
The left hand should be kept free to retract using the mouth mirror

24. INSTRUMENT EXCHANGE
All instrument exchanges between the operator and assistant should occur in the exchange zone below the patient’s chin and several inches above the patient’s chest.
Instruments should not be exchanged over the patient’s face.
Any sharp instrument should be exchanged very carefully
Each person should be sure that the other has a firm grasp on the instrument before it is released.

25. MAGNIFICATION
Magnification achieved with either surgical loupes or dental microscopes enlarges the operating site.
Both allow the clinician to visualize features not otherwise perceptible to the naked eye.

26. The Benefits Of Magnification
Magnified Image
Brilliant Illumination
Better Posture and Improved Comfort
Increasing Accuracy
Improved Dental Care
Additional Treatment Options

27. THANK YOU…