Is your low speed handpiece not working? The problem could be with your contra angle. Save time and money by determining if your problem is occurring in the contra angle’s latch head, the contra angle’s sheath, or both.
*For the purpose of this Tech Tip, we are using a Star contra angle with a latch head and a Midwest contra angle with a latch head. The same principles can be applied to most slow speed contra angles.
More often than not, when your low speed handpieces are not working properly, the problem is occurring in the contra angle attached to your motor. This can be determined quickly by simply removing the contra angle from the motor and applying normal operating air pressure. If your motor works fine when applying air pressure, your issue is most likely located in your contra angle.
This Tech Tip will be dealing with problems occurring in your contra angles. If your motor, without any contra angle attached, does not run when normal operating air pressure is applied, your motor is the problem and will need to be sent to us for repair. If you need to send your motor to us for repair, just let us know and we will email you a prepaid UPS return label.
There are two parts of most contra angles. A contra angle sheath and a contra angle head. In the illustration below, we used a Star contra angle with a swing latch head. The same principles can be applied to a contra angle with a push button head (“auto latch head”), or a push button friction grip head (uses a standard high speed type bur).
Now that you have determined that your problem is occurring in the contra angle, determining where the problem is occurring in the contra angle can save you a lot of time and money. Sending your contra angle off for a repair can take time, and if sent to the wrong place can be very expensive. Both parts of the contra angle handpiece, the contra angle latch head and the contra angle sheath, are easy to replace. Due to the fact that the problem is usually occurring in one or the other, you can cut your costs in half. This is one of the easiest chair side/in office fixes!
Follow these steps to determine where your problems are occurring:
Step 1: Remove the head from the contra angle sheath and set head aside. Most of the time this can be done by simply unscrewing the collar on the head with your forefinger and thumb. The collar can sometimes be difficult to unscrew by hand and will need to be unscrewed by using small pliers. Make sure to remove the oblique shaft (see illustration) as well.
*For illustration purposes we are using a Star contra angle with a swing latch head.
Step 2: Reattach the contra angle sheath (without head) to the motor. Connect your motor with contra angle sheath attached to your air supply and apply normal operating air pressure.
2a. If the motor runs fine and the contra angle sheath seems to be spinning well internally, the problem is most likely occurring in the head. This is the most common issue with contra angles. To fix this issue, simply replace the contra angle head with a new compatible head. Our part number for this head is EHN-20L. Follow the links below to find your compatible contra angle head.
2b. Apply normal operating air pressure with the motor and contra angle sheath attached (without a head) to your air supply. If the motor does not run when air pressure is applied, or the motor runs but the entire contra angle sheath itself spins on the motor, the problem is most likely occurring in the contra angle sheath. You can simply replace the contra angle sheath and reattach the contra angle head. Our part number for this sheath is SHS-STUNH. Follow the links below to find your compatible contra angle head.
Note: if your problems are occurring in the contra angle sheath, there is a chance that you may have a problem in your head as well. This is due to the fact that problems in the contra angle sheath take longer to develop. This means that the head has been in service a long period of time as well and therefore might be ready to be replaced. If you do have problems occurring in both the contra angle head and contra angle sheath, you would be better off buying a complete contra angle. We sell high quality, complete contra angles as well as contra angle sheaths and contra angle latch heads at great prices with great warranties. See below for products numbers and links to purchase on our website.
Being able to isolate where your problems are occurring with your handpieces and providing simple fixes and solutions is what our Tech Tips are all about. Be on the lookout for more Tech Tips in the future.
We are here to help! At The Turbine Source, we feel our technical support is second to none. All questions or requests are worth asking! Please let us know if you have any questions at all about your handpieces. With over 30 years of experience, with all makes and models of handpieces, chances are that any issue you run into we have had to deal with that issue as well. We would be happy to help in any way we can, so please feel free to contact us!
Josh Gross is the owner and founder of The Turbine Source with over 30 years of experience in the dental handpiece and dental handpiece turbine business.
Follow the links below to find the contra angles, contra angle heads, and contra angle sheaths you're looking for!