DENTAL CHAIR POSITION, INSTRUMENT GRASP.pptx

dentalchair position

1. CHAIR POSITION, INSTRUMENT GRASP and finger rests BY: Dr. Ankita Rath

2. INTRODUCTION While working on a patient chair, positioning plays an important role. One should be sure that clinician should sit with back upright on operating stool to avoid spine and back problems. If a patient and clinician maintains proper position and posture during treatment, they are less likely to get strained, fatigued and shall be more efficient and have less chances of getting musculoskeletal disorders. Patient should be seated so that all his body parts are well supported. Patient’s head should be in line with his back, whether the dental chair base is parallel or slightly at an angle to the floor. Dental chair should be designed in such a way that it should provide maximum working area to the operator.

3. OPERATOR POSITION OBJECTIVES: (1) Accessibility to the operating field. (2) Visibility of the operating field without any obstruction. (3) Comfort of both operator and patient. (4) patient Safety

4. ZONES OF OPERATING FIELD:

5. ZONES OF OPERATING FEILD Operator’s zones : 7 o’clock position to 12 o’ clock position. This is the zones where the operator sits. •Transfer Zone : 4 o’ clock to 7 o’ clock position. Zone where instruments and materials are transferred between the operator and assistance.

6. Assistance Zones : 2 o’ clock to 4 o’ clock This is the zone where assistant sits. • Static Zones: (1) 12 o’ clock to 2 o’clock. (2) This is the zone which contains all auxiliary materials

7. Patient’s position (1 ) UPRIGHT POSITION : This is the initial position of chair from which further adjustments are made. (2) RECLINED AT 45 ˚ In this position, chair is reclined at 45˚. Here mandibular occlusal surface are almost at 45˚ to the floor. (3) ALMOST SUPINE In this position, patient is almost lying as the name indicates. Patient’s head, knees and feet are approximately at same level.

8. PATIENT’S POSITION UPRIGHT INCLINED AT 45˚ SUPINE

9. OPERATOR’S POSITION RIGHT FRONT POSITION: (7 o’clock position): Operator sits in front of the patient. It helps in examination of the patient. Working areas include- Mandibular anterior (facial side), mandibular posterior teeth (right side), maxillary anterior teeth. RIGHT POSITION : (9 o’clock position): In this position dentist sits exactly right to the patient. Working areas include- Facial surfaces of maxillary right posterior teeth, Facial and occlusal surfaces of mandibular right posterior teeth.

10. RIGHT REAR POSITION: (11 o’clock ): In this position, dentist sit behind but slightly right to the patient and the left arm is positioned around patient’s head. This is referred as the universal operating position. This position provides access to all areas of oral cavity either using direct vision or using indirect vision with the help of mouth mirror. DIRECT REAR POSITION: (12 o’clock ): Dentist sits exactly behind the patient and looks down over the patient’s head during procedures. Working areas includes lingual surfaces of mandibular anteriors .

11. POINTS TO REMEMBER WHILE DOING PATIENTS: Do not sacrifice good operating postures as it will decrease visibility, accessibility and efficiency. Maintain proper working distance during dental procedures. Operator’s eye should be 14-16 inches from the treatment site. While working on a mandibular arch, the mandibular occlusal surface should be 45˚to the floor. In maxillary arch, maxillary occlusal surface should be perpendicular to the floor. Avoid/minimize body contact with the patient.

12. INSTRUMENT GRASPS The different instrument grasps recommended are: (1) MODIFIED PEN GRASP (2) INVERTED PEN GRASP (3) PALM AND THUMB GRASP (4) MODIFIED PALM AND THUMB GRASP

13. MODIFIED PEN GRASP It is a variation in pen grasps. Modified pen grasp is similar to the pen grasp except the operator uses the pad of the middle finger on the handle of the instrument rather than going under the instrument. Most common posture of holding a dental instrument between thumb pads, index finger and side of middle finger either supporting the shank or placed lower on the handle. The fourth finger –ring finger is used as fulcrum. Positioning of the fingers in this manner creates a triangle of forces or tripod effect, which enhances the instrument control. Mostly used for mandibular teeth.

14. MODIFIED PEN GRASP

15. INVERTED PEN GRASP This is similar to modified pen grasp except that the hand is rotated so that the palm faces more towards the operator. The finger positions of the inverted pen grasp are same as for the modified pen grasp. This grasp is commonly used for preparing a tooth in lingual aspect of maxillary anterior and occlusal surface of maxillary posterior teeth.

16. INVERTED PEN GRASP

17. PALM AND THUMB GRASP This grasp is same as holding the knife for peeling the skin of an apple. Here instrument is grasped very near to to its working end so that the thumb can be braced against the teeth so as to provide control during instrument movements. Shaft of the instrument is placed on the palm of the hand and grasped by the four fingers to provide firm control, while the thumb is free to control movements and provide rest on an adjacent tooth of the same arch. To achieve the thrust action with the fingers and palm, the instrument is forced away from the tip of the thumb which is at rest position. The grasp has limited use and occasionally used while operating on maxillary anterior teeth.

18. PALM AND THUMB GRASP

19. MODIFIED PALM AND THUMB GRASP Instrument is held like the palm grasp but the pads of all the four fingers press the handle against the palm and the pad and the first join of the thumb. Here the tip of the thumb rests on the tooth being prepared or the adjacent tooth. It provides more control to avoid slipping of instrument. This grasp commonly used for maxillary anterior.

20. MODIFIED PALM AND THUMB GRASP

21. FINGER RESTS Finger rests are used to stabilize the working hand while instrumentation. It helps in confining the instrument to the working area. They help in preventing the accidental injury due to slippage of the instrument. Rests should be placed on tooth or bony surfaces and not on soft tissues. Finger rests may be Intraoral or Extraoral.

22. TYPES OF FINGER RESTS INTRAORAL FINGER RESTS: Conventional finger rest Cross-arch finger rest Opposite arch finger rest Finger on finger • EXTRAORAL FINGER RESTS: Palm Up Palm Down

23. CONVENTIONAL: In this the finger rest is just near or adjacent to the working tooth. CROSS-ARCH: Here the finger rest is achieved from tooth of opposite side but of same arch OPPOSITE ARCH: finger rest is achieved from tooth of opposite arch. FINGER ON FINGER: Here the rest is achieved from the index finger or thumb of non operating arch. PALM-UP: Here rest is achieved by resting the back of the middle and ring finger on the lateral aspect of the mandible on the right of the face. PALM DOWN: Here rest is obtained by resting the front surface of the middle and ring finger on the lateral aspect of the mandible on the left side of the face.

24. PALM UP AND PALM DOWN