There is an increase in the efficiency of the dentist through the use of a full time trained chairside assistant.

There is a decrease in the muscular stresses involved with the practice of dentistry through conservation of muscular activity, adherence to the principles of balanced posture.

The dentist is able to concentrate their skill and judgment on the tasks directly associated with patient care.

The concept of four-handed dentistry described by Dr. G.E.Robinson and others will be reviewed. Research shows that production can be increased by 100% and simultaneously stress and fatigue will be reduced by 50% -70%.

The following will describe the principles of four-handed dentistry, areas of activity, work simplification and motion economy. Also covered is the proper selection and arrangement of operatory equipment according to the criteria as established by the research completed at the University of Alabama School of Dentistry.

The Concept

The two most frequent issues facing practicing dentists are (1) the need to minimize stress and fatigue and (2) the need to maintain or even increase productivity without sacrificing the quality of care. As the practice of dentistry has become more complex with intervention at almost every level by third parties and government agencies, the intrusion on the dentist's chairside time has become critical. The use of this concept of four-handed dentistry will enable the practitioner to spend their time at chairside more efficiently. The dentist has many choices as to what they will do with time saved: One can see more patients, spend more time with each patient, or spend the time in other activities. Four-handed dentistry, therefore, should not be equated with the automatic transition to a high volume practice. Rather, we should see it as the effective use of the principles of time and motion allowing the practitioner more schedule flexibility.

This system of four-handed dentistry is based on the following principles:

1. POSITIONS: The dentist (or hygienist), assistant and patient are seated and positioned properly.

2. ASSISTANT UTILIZATION: The operator uses the skills of competent, full-time chairside assistant.

3. TREATMENT ORGANIZATIONS: Every aspect of the patient's treatment is organized and repetitive tasks simplified to take maximum advantage of the chairside time available.

4. EQUIPMENT ARRANGEMENT: The equipment used is selected carefully and positioned properly to enable the operating team to use the principles of work simplification and motion economy.

Positions

It is not enough that the operator and the assistant merely sit during patient treatment. They should adhere as strictly as possible to the principles of balanced posture. The operator should sit with their thighs parallel to the floor, feet flat on the floor, neck and back relatively straight with forearms parallel to the floor. This results in an operating distance of roughly fourteen inches. Additionally, the lower visual eye fields should be used in an effort to offset the strain usually felt in the neck when the head is continually tilted forward.

The assistant will likewise sit with balanced posture. The only difference is that their feet are rested on the ring of the assistant stool, since their position is usually four to six inches higher than the operator.

Patients are positioned with their head at the uppermost area of the chair and in the supine position for most procedures. This position is defined as one in which the patient's head and knees are at the same level on a plane parallel to the floor. One should not tilt the chair excessively toward the Trendelenberg position for routine procedures. Rather, the operator should take maximum advantage of the mobility of the patient's head to tilt and turn the patient's head to afford better visibility and access.

Occasionally, there will be patients who are unable to tolerate the supine position. However, it has been our experience that this is a very small percentage of patients, and they are dealt with on an individual basis. Dentistry is fraught with many occupational hazards, many of them related to the long-term use of poor posture by the dentist. Rather than exposing oneself to these hazards, we should, within reason, ask that the patients accommodate our balanced posture if at all possible.

When an operator is treating a tooth positioned in the Mandibular arch, a different position for the patient may be indicated. The easiest way to change a patient to what is termed the "Mandibular seated position" from the supine position is to (1) lower the chair base maximally and (2) elevate the back of the patient's chair until the patient's mouth is at a position that will enable the operator to work with their forearms parallel to the floor. This change is easily accomplished with pre-positioned programs in most patient chairs available today.

The use of balanced posture is sometimes difficult to master. However, the dentist who is dedicated to changing to this more healthful position in their practice will find their muscular fatigue greatly diminished. If you have not been using the principles of balanced posture in your practice, you may find yourself out of position frequently without realizing it. It is helpful if the assistant can remind you of this by simply asking, "Are you comfortable, Doctor?" This should prompt you to evaluate your posture and correct any deficiencies.

Assistant Utilization

In the practice of Four-Handed Dentistry, research shows that the assistant makes 92% of all chairside movements. Dentistry has evolved to an era where the dentist need not concern themselves with the location, in the operatory, of instruments, materials, and medicaments to be used during a patient's appointment. The chairside assistant has taken over those duties, and in some states, has been allowed to do much more under the direct supervision of the practicing dentist. The effective use of a chairside assistant is dependent on the dentist either training the assistant or hiring an assistant who has been previously trained in the practice of four-handed dentistry. Many procedures can be accomplished in less time by delegating duties to the dental assistant that they may legally perform as specified in the state's dental practice act. There duties are termed either total-duty delegation (i.e., taking and processing radiographs, placing rubber dams, placing liners, et.), or partial delegation, (assisting the dentist chairside). One should never delegate duties that the auxiliary is neither trained to perform, nor is legally allowed to perform.

Treatment Organization

Though the scope of this article is limited to the concept of four-handed dentistry, as it relates to patient treatment, the need for practice organization, in general, should be incorporated in one's efforts to streamline the practice. In this regard, one should consider: (1) facility design (2) equipment selection (3) business system (4) staffing
(5) appointment system (6) recall procedure (7) office manual
(8) inventory system.

Patient treatment organization involves examining the way in which all aspects of the treatment is accomplished and analyzing ways that the operating team could more effectively perform these procedures. Careful thought should be given to the proper placement of instruments, materials, and medicaments used during treatment. Any time an assistant has to leave the operatory to retrieve an item needed in the patient's treatment, treatment efficiency suffers. As one analyzes the treatment performed, the team should pre-plan effectively to insure that all necessary items are positioned well within reach of the respective team member. Dentists should concern themselves with being able to focus their efforts on the oral cavity. The area of concentration for the dental assistant is somewhat larger, since they must be prepared to bring all necessary items needed in the treatment to the dentist. The use of mobile cabinets and pre-set tray systems will greatly facilitate the dental assistant's efforts by allowing the pre-positioning of necessary items used during the various procedures.