Pros and cons are numerous with the electric dental drill as compared to the pneumatic or air driven hand piece. Some of the advantages are of the electric drills are their smooth operation, low noise level, and continuous torque.
The doctors that I have talked to have sited the following advantages for the electric dental drill. Electric drills offer more torque with less noise and vibration. They also offer a greater range of speeds with a forward and reverse option. These drills also offer greater flexibility with the proper attachments. Most doctors report a smoother more accurate reduction of dentin.
The same doctors site these disadvantages. They are larger and heavier which can effect user fatigue. They are much more expensive to purchase and repair than the traditional air drill. Some have electric drill repair costs exceeding $600.00 per unit. They do require a learning curve to use properly. There are also infection control issues, we will address these issues in more detail below.
Pneumatic or Air driven high-speed drills have typical speeds up to 400,000 rpm. Traditional low-speed pneumatic motor drills have maximum speeds up to 40,000 rpm. Since these motors run to 40,000 rpm, most manufacturers do not like to market them as high-speed drills when referring to electric drills, although they are marketed and sold for gross reduction.
Note: The 1:5 attachment provides a speed range of 5,000 to 200,000 rpm. Most doctors are referring to this as a high-speed and the 1:1 as a low speed.
When drilling dentin with a traditional high-speed hand piece the rpm will reduce to about 200,000 rpm due to the torque reduction. The electric hand piece will experience very little loss of torque and continues at about 200,000 rpm.
So far, most electric hand pieces do not meet the some infection control requirements. There are still some micro-motors that can’t withstand the autoclave. The housing is not the problem but the internal parts may not withstand the process.
When purchasing a new unit you may want to make sure that the manufacturer has addressed dental unit waterline (DUWL) asepsis. Service procedures to improve the quality of water used in dental treatment are available. Recommended methods include self-contained water systems with a filtration system, and chemical treatment. Ask about replacement parts for your electric hand piece repair purposes.
Note: If you use tap, or distilled water with <500 CFU/mL of bacteria in a self-contained water system you may not eliminate all bacterial contamination in your water treatment. Bio-films in the water must be controlled.
Chemical germicides are the best solution for bio-film contamination. Check with the manufacturer to make sure that this issue has been fully addressed.