How to Find the Perfect Contra-Angle Handpiece
Air-driven v electric handpieces
The choice between air-driven turbines and electrically powered contra-angles is based on personal requirements for efficiency and ergonomics, but may also be influenced by the desire to reduce aerosol generation in line with infection control protocols introduced during the Covid-19 pandemic.
Air-driven turbines are more lightweight in design and typically less expensive than electric handpieces. However, because they are only driven by a small rotor, the power of air turbines is limited and dependent on contact pressure on the tooth.
Air-driven turbines are typically louder when in operation and speed cannot be controlled. This inability to deliver the required operating speed can lead to greater wear on the handpiece and increased heating of the tooth.
Speed-increasing contra-angles on the other hand can adjust speed in the range of around 10,000 to 200,000 rpm. Because of this, electric contra-angles are less noisy to use and can provide a finer degree of control.
The consistent torque of electric contra-angle handpieces mean they have a higher efficiency at cutting various materials compared to turbines.
Speed increasing handpieces are also more effective at reducing aerosol generation and therefore better for infection control. This is because the greater control of speed helps reduce the intensity of particle distribution and limit the water spray generated.
Inside contra-angle handpieces are high-precision ball bearings, gears, fibre optics, filters and seals. Contra-angles can only work properly if these components are cleaned and maintained correctly on a regular basis.
Some contra-angles are suitable for washer disinfectors and autoclaves for easier and quicker sterilisation.
This is true of the BA Ultimate BA250LT and BA200LTS speed-increasing contra-angles. The titanium body of these handpieces can also withstand chemicals and the sterilization process better than chrome plate.
BA contra-angles can also be manually cleaned and lubricated in accordance with manufacturer guidelines.
It is important to consider ergonomics when picking the perfect handpiece. Design features that should be evaluated include weight and grip.
The lighter the contra-angle, the more comfortable it should feel in the dentist’s hands. Modern contra-angles are designed to be lightweight and perfectly balanced - ideal for using for extended periods of time without causing strain.
Some handpieces, such as the BA250LT and BA200LTS, come with a PVD "smart coating" for enhanced grip.
Every contra-angle comes with a gear ratio which indicates what dental procedure the contra-angle can perform.
Contra-angles with 1:5 gear ratios are typically recommended for cavity prep, crown prep and sectioning existing prosthetics.
1:1 ratio indications include adjusting ceramics, refining prep and removing caries.
A good speed increasing handpiece should have sufficient cooling features to reduce the heat produced by the friction between the bur and tooth surface.
Excessive heat transfer can result in inflammation and necrosis of the pulp. Most electric contra-angles now have built in coolant ports to spray water at the bur-tooth surface to improve cooling efficiency and minimise pulp injury.
For optimal cooling, quadruple (4-port) spray is a feature to keep an eye out for.
Product quality should always be weighed up against cost to ensure you are getting the most for your money.
B.A. International regularly offers free stock deals on its speed-increasing contra-angles and other handpieces to help your practice budget. See all current offers here.
To find out more about what value BA handpieces can offer your practice, see our blog ‘3 Reasons BA Dental Handpieces Offer the Best Value’.
Our handpiece specialist Jack is also available to answer any questions on our handpiece range, and can be contacted directly on 01634 878759.