1. Essentials of 4-Handed Dentistry
Dena 320
Lesson III
Deborah Bell

2. Major Goal in the Practice of Dentistry
Deliver high quality service
Deliver service as efficiently as possible

3. Dental Procedures May Be Divided Into 3 Parts
Preparation
Patient treatment
Clean up
A second assistant may be utilized to prepare and clean up allowing first assistant to be
Full time chairside
Thus no down time between patients

4. Concepts important to teamwork dentistry
Done in seated position
Patient position
Work area used
Operatory equipment
Availability of second assistant
Instrument exchange
Use of oral evacuator

5. 2 Basic Issues of Interest in Dentistry
Minimizing stress and fatigue for the dentist
Increase productivity while maintaining high quality standards

6. Dentistry is stressful and fatiguing
Operator must maintain high level of concentration
Keep a high level of clinical excellence by his/her ability to
Meet variety of patient needs
Perform delicate skills with limited access
Manage schedule and the practice

7. 4-Handed Dentistry Reduces Stress
Increasing efficiency
Thus increasing productivity to meet demands of public

8. Concept of 4-Handed Dentistry
Operating in a seated position
Employing the skills of a trained assistant
Organizing every component of the practice
Simplifying all tasks to the maximum

9. 3 Major Aspects of 4-Handed Dentistry
Work simplification
Motion economy
Body mechanics

10. Motion Economy Conservation of motion Eliminate excess harmful motion
Movements consume time and produce fatigue
Eliminate excess harmful motion

11. Classification of Movements
Only fingers
Signal for instrument transfer
Class II
Fingers and wrist
Use of an instrument
Class III
Finger, wrist and elbow
Mix amalgam, activating chair buttons

12. Class IV Class V Entire arm from shoulder
Adjusting light, rubber dam placement
Class V
Entire arm and twisting of the trunk

13. Class IV and V Most fatiguing
Requires to look away from field then refocus
Results: eyestrain and headaches

14. Class I, II, III Preferred for DA and Dr
Involves less muscle activity and saves time
Allows eye contact concentrated on operative field

16. Positioning the Patient and the Operative Team

17. Objectives of a Favorable Seated Position
Access to the operative field
Good visibility
Comfort for the operative team
Relative comfort and safety for the patient

18. Zones of Activity Patient in a supine position
Using center of patients face as a clock
Zones designated as time

19. Right Handed Operator Operator zone Static zone Assistants zone
7 – 12o’clock
Static zone
12 – 2o’clock
Assistants zone
2 – 4 o’clock
Transfer zone
4 – 7 o’clock

20. Left – Handed Operator Operator zone Transfer zone Assistant zone
’clock
Transfer zone
5 – 8 o’clock
Assistant zone
8 – 10 o’clock
Static zone
10 – 12 o’clock

21. Positioning the Operator
Work environment is adapted to the operator
Operator positioned first then
Patient
Assistant
equipment

22. Characteristics of Balance Posture for Operator
Operators thighs parallel to floor
Entire surface of seat used to support weight
Backrest supports back without interference
Forearms parallel to floor when hands are in operative position
Elbows close to the body
Back and neck reasonably upright with top of shoulders parallel to floor

23. Distance of approximately 14 – 18 inches between the operator’s nose and the patients oral cavity maintained
Operative field is operators midline

24. Positioning the Patient in the Working Position
Oral Cavity at height of operator’s elbow
Head placed at upper end of chair and slightly to operators side of chair
All patients are seated from the head down

25. Steps to position a Patient
Adjust back approximately 60 degrees to vertical
Raise chair to height patient can easily be seated
Raise arm of chair
Once patient is seated
Armrest down
Raise chair approximately 10 inches to allow Dr. to position himself

26. Continue lower chair back until following relationships exist
Tilt seat portion back so foot rest is raised approximately 6 to 8 inches
Lower back of the chair until patient is about ½ way toward a horizontal position
Pause to allow patient to adjust
Continue lower chair back until following relationships exist
Imaginary line from patients chin to the top of ankles is parallel with floor

27. Once seated – Observe Patient
Lying flat with little bending at waist
Similar to sleep position
Legs slightly lower than head – if higher might cause – pt. Anxiety/circulation problems.
Patient in supine position

28. Plane of the patients forehead is also parallel with the floor

29. Lower chair to operators lap
Approximately 1 inch above knees of operator

30. Supine Position Universal position for all working positions
Patient is lying down facing upwards
Slight modifications only allowed as patients needs are assessed

31. Patient Dismissal
Patient dismissal should be accomplished by reversing the steps of seating the patient
Remember to pause for the patient on the way up as well
Most important patient dismissal precaution
Encourage the patient to remain seated to reestablish their equilibrium

32. Positioning the Assistant
Must be able to see and have favorable access to be able to
Retract tissues
Evacuate fluids
View to anticipate needs of operator
Maintain clear field

33. Position of Assistant 3 o’clock position for all quadrants
Right handed operator
9 o’clock position for all quadrants
Left handed operator
Stool positioned so edge toward the top of patients head is in line with the patients oral cavity
Stool as close to chair as possible
Stool elevated to top of assistants head is 4 – 6 inches higher than the dentist

34. Body support arm adjusted to support upper body just under rib cage
Back erect
Body support arm adjusted to support upper body just under rib cage
If stool positioned properly mobile cart can be pulled over lap
Approximately 2 inches below elbows

35. Work Simplification Major advantage – Doctors Health
Definition – finding an easier way to do a task more efficiently – less pt. Treatment time spent
Work simplification studies indicate 4 areas to make dentistry delivery easier

36. Rearrangement of instruments and equipment
Combination
Elimination
Thus simplification

37. Rearrangement
Position all instruments and equipment in favorable spot to the team not vice versa to minimize movements of team

38. Elimination
Eliminating unnecessary movements, procedural steps, instruments and equipment
Saves time and efforts

39. Examples of Elimination
Unnecessary bur changes
2 handpieces
Unnecessary instrument exchange
Use instrument to max. before returning
Use supplies and materials that can save time
Premeasured capsules
Eliminate seldom used items
Plan for usual not unusual

40. Combination Combining steps
Combining purpose of equipment and instruments
Combining uses

41. Examples of Combination
Double ended instruments
Using instruments for more than one purpose
Air/water syringe together
Cements used as base and cementing agent

42. Simplification
Last because this should occur after all rearranging, eliminating and combining activities have been completed
Basic idea – to minimize number of variables in all aspects of the practice
Streamlining process geared to promote predictable routines in the work pattern

43. Standardization of Work Procedures
Contributes to effective teamwork by being able to anticipate the dentist’s needs
Contributes to efficiency/production

44. Examples of Standardization for Work Simplification
Arrange steps into smooth sequence
Use preset trays in order of use from left to right
More than one op.
Each treatment room identical in equipment
And materials

45. Sit Down Dentistry Body mechanics/task performance studies
Seated worker uses 27% less energy
Seated worker has 17% greater life expectancy
Production increases from 33 – 78%
Seated in a balance posture concept
½ the efficiency of a D.A. Is the result of working with a well-organized dentist who practices 4-handed dentistry

46. THE
END