The following are just a few samples of potential equipment a dental team may look at when contemplating the purchase of new equipment. These are simply schematics and do not represent any one given product. Look at the schematic drawing in the following figures and identify potential problems as well as good characteristics where applicable. Which of the criteria do these set ups include? Which are they lacking?
Remember, you are likely to find equipment that has some very good characteristics and lacking in others, but be certain that you search for the styles that can most likely satisfy the criteria outlined for ergonomic equipment that will assure comfortable practice for the dental health team.
The chair has a thin back but has a wide wing back which would deter the assistant and operator access to the patient. The arm rests, though present, appear thin and not too supportive.
The light is attached to the unit which is attached to the chair, so it would move as the patient is raised and lowered. It also has adjustments on both sides for easy access.
Concerns are the presence of a cuspidor and a bracket table. The cuspidor would interfere with the assistant’s stool and is not used in true four‑handed dentistry. The bracket table is not used as it would cause instruments to be placed haphazardly on the tray and would not be within a 21 inch radius of the assistant’s hand. The instruments attached to the unit are also not accessible to the assistant for transfer.
The chair has a wide back that causes the assistant and operator to be moved further from the patient. The back does have a relatively thin back and adjustable headrest, a wide back prevents the assistant getting close to the patient and no armrests cause discomfort to the patient.
The split unit makes it difficult for the assistant to access the handpieces on the operator’s side of the chair. If the operator must reach for the instruments then the eyes must refocus to the operative site.
The mobile cabinet does not have extra storage for backup instruments but there does appear to be adequate fixed cabinetry for back up storage. However, it is not easily accessible when the assistant is seated.
The dental light is affixed to the ceiling and will require adjustment when the patient is moved up or down. The light does have controls on both sides for adjustment.
The dental stools appear well padded and supportive. It is not clear if there is an easy adjustment for the assistant to raise or lower the stool without moving off the seat.
This chair has a narrow thin back and provides the criteria for an ergonomic chair in true four‑handed dentistry.
The unit is in the rear and though it could be easily accessible it may create some problems when the assistant is transferring instruments during a complex procedure.
The position of the cart top can interfere when the assistant is reaching for materials on the fixed cabinetry in the back. Some back up materials could be placed on the fixed cabinetry to the assistant’s right side, but would require a Class IV or V motion to reach.
The stools appear to meet the criteria identified earlier.
This set up is quite ideal for true four‑handed dentistry. The chair, unit, and stools meet the criteria outlined for true four‑handed dentistry.
The fixed cabinetry in the back could have more access to back up equipment but the mobile cabinet in this arrangement does house many back up instruments.
It is not clear if this assistant’s stool provides the capability to raise and lower the stool without moving off the seat.
The light is attached to the ceiling and will require adjustment as the patient is moved up or down.