Increasing Productivity by Effective Use of Four-Handed Dentistry – Part 3: Instrument Transfer Technique
The Single-Handed Transfer

The single‑handed instrument transfer with a right‑handed operator is illustrated in the following procedural outline (Figure 9).

• Assemble instruments in sequence of use and place the instrument tray as close to the patient as possible. The tray may be positioned in a vertical or horizontal position (Figure 10).

• If a tray or cassette is not used as in some dental specialties, prepare the materials in a logical sequence of use (Figures 11 & 12).

• Place auxiliary equipment such as the anesthetic syringe, or rubber dam on the mobile cabinet farthest from the patient.
• At the beginning of the procedure simultaneously pass the mirror with the right hand and the explorer with the left hand (Figure 13).

• Pick up the instrument to be transferred in the left hand and position it between the first finger and thumb at the non-working third of the instrument (Figure 14).

• Rest the instrument on the middle finger, making certain that the working end is positioned for the correct arch and position it within 10-12 inches from the operator’s hand in readiness for a transfer when needed (Figure 15).

• The operator signals for an exchange by moving the instrument being used from the tooth and bringing it outside the mouth. When possible, a finger rest may be maintained (Figure 16).

• The assistant grasps and tucks the used instrument toward the wrist with the pick up portion of the hand (Figure 17).

• The new instrument is delivered into the operator’s hand with the delivery portion of the hand and the operator returns to the mouth with the new instrument (Figure 18).

• With the thumb, the assistant rolls the instrument from the palm up to the ring finger until it is above the first knuckle. Take care to avoid puncturing the gloves (Figure 19).

• Fold the index and middle fingers under the handle and return the instrument to the holding position (Figure 20).

• If the instrument is not to be used again, it can be returned to the proper position on the tray.
• When the air‑water syringe and the oral evacuator are used, the assistant places the air‑water syringe in the right hand to free the other for the instrument transfer (Figure 21).

Bulky instruments can be transferred in the same single handed exchange as described above. Many dental units, such as the split unit, prohibit effective handpiece transfer since the handpiece is outside the 21‑inch radius of the assistant’s hand. This unit placement leads to decreased effectiveness in terms of time and motion. When a transthorax unit is used and handpieces are within the transfer zone, the assistant should then utilize the following procedure:

• The handpiece is made parallel with the instrument to be exchanged (Figure 22).

• The return of the handpiece in the pick up portion of the assistant’s hand is done in the same manner as any other instrument even though it is bulkier. For this reason, the two fingers used in the pick up method provide greater stability (Figure 23).

• The handpiece is then returned to the dental unit.