Thank you for following our series on helping Dental Professionals choose the right vacuum for their clinic by comparing the different types of Dental suction units. The goal of this series is to help Dental Professional better understand Dental Vacuum systems, giving better insight when choosing one for a clinic.
Today’s segment will be reviewing a few unknown terms in Dental Vacuum, as well as provide a better grasp on the relation of HVE/SE to vacuum strength.
Definitions
User – a High Volume Ejector (HVE) or two Saliva Ejectors (SE).
CFM or Cubic Feet per Minute - is the measure of air flowing through a vacuum system. CFM is the speed of the airflow. CFM equates to a car’s top speed.
Inches of Mercury- Suction is measured in inches of mercury (hg). This is the measurement of the vacuum’s ultimate power. This can be compared to a car’s horsepower.
Diameter of HVE and SE
The standard HVE suction tool is said to be ½’ diameter inlet, but has an internal opening of 5/16” diameter. The maximum amount of air that can enter a 5/16” diameter hole at 5” of Hg is 11.07 cfm and at 10” of Hg is 14.64 cfm.
The standard SE suction tool is said to be ¼” in diameter inlet but has an internal opening of 1/8”. The maximum amount of air that can enter a 1/8” diameter at 5” of Hg is 2.04 cfm and at 10” of Hg is 2.55 cfm.
NOTE-
The purpose of HVE and SE evacuation tools is to remove liquids and debris from an oral cavity. As the material enters the suction tips, it reduces the diameter, which reduces the airflow entering the system.
Why is this important to know? When considering a new dental suction pump, it is good to understand users (HVE and SE) and how much they draw on your vacuum power.
Users in Your Clinic
Unless you are in the know, very few Dental Professionals often consider how many users of vacuum are in a clinic. To go further, of those users, how many of them have a completely open valve, using the full 14.64 CFM produced by the vacuum. In a normal clinic, not everyone is using suction tools at the exact same moment. The staggered use makes a huge impact on how much flow, or CFM, a pump has to move.
Some manufacturers of High Flow vacuum systems would have you believe that every handheld suction tool in your clinic is in use and fully open 100% of the time. This is called an open flow demand, which is very unlikely in standard dental procedures. High Flow vacuum systems thrive open flow use, as they require a large influx of air to function at peak efficiency. Though it is common for an Open Flow test to be used when testing the strength of vacuum at each operatory, it isn’t a true representation over how vacuum truly works in a Dental Practice. Most Dental Practices would require a Low Flow vacuum system, as they are designed with most dental procedures in mind.
Follow Us
To understand the difference between a High Flow and Low Flow dental vacuum, and which system is best for your practice, follow the next few segments of this series. Over the next few weeks, we will be providing detailed differences between the two types of vacuum systems.