Tag Archives: equipment dental

  • Practice Tips #77: Getting Comfortable With Nitrous

    Nitrous Oxide (N2O) can be a valuable addition to the dental office analgesia armamentarium. Having a patient that is relaxed can lead to more successful outcomes.

    N2O is delivered to the patient via a nosepiece or “hood.” Various equipment manufacturers have their own designs of hoods that are designed to be used either with or without a “scavenger system” (#71-30 or #71-301).

    Scavenging Circuit

    A scavenger system is designed to evacuate exhaled gases to minimize contamination of the ambient air within the operatory. The scavenger is connected to your vacuum system (via the HVE) to pull the gas away and vent it to the outside atmosphere (along with your main central vacuum vent).

    To prevent the vacuum from pulling all of the gas before the patient can aspirate (and receive the benefits), all scavenging systems have a vacuum valve and gauge incorporated into the system. This valve controls the level of vacuum so the excess gas can be safely evacuated while the patient still receives an appropriate dose of N2O.

    The gauge pictured below is typical of such devices. It has inlet and outlet connectors for the vacuum line, a control valve to adjust the flow, and a gauge to indicate the current flow setting. Note the green “safe” area indicated on the face of the gauge. Most systems incorporate clear labeling like this to make it easy to set the gauge correctly.


    As the scavenger connects to a HVE valve, there is typically a 7/16” o.d. fitting at the end of the scavenger circuit. All HVE’s sold in the US are designed to take a standard 7/16” tip. This is also the size of the various aspirator tips on the market. These are standardized sizes.

    The hood, however, will vary considerably from manufacturer to manufacturer. Most hoods will have two “inlet” connections for gas to flow to the patient’s nose from the flowmeter. If using a scavenger, there will also be one or more “outlet” hoses pulling the excess (and exhaled) gas away from the patient (and operatory). As an additional means of limiting flow (in addition to the vacuum valve and gauge already discussed) these “outlet” hoses are typically smaller in diameter than the “inlet” hoses. As these hoses fit over connectors, they are measured by inside diameter (i.d.). Whenever you need to replace one of these hoses, always measure the inside diameter to be sure of the proper size. Unlike HVE tips, there can be some variance here so it’s important to know what you have.

    The Accutron scavenger circuit and hood has four connections. This system is also used on Belmed nitrous units. It uses two inlet hoses of 3/8” i.d. (these hoses connect to the side of the hood) and two outlet hoses of ¼” i.d. (these hoses connect to the scavenger “hub” that snaps onto the front of the hood).


    The use of nitrous oxide in your practice can be an important tool in offering your patients a relaxing experience, enhancing recall rates, and resulting in more successful procedures. The scavenging circuit plays an important role in your anesthetic system, allowing you to safely deliver a controlled flow of nitrous oxide and oxygen to your patient, while keeping staff protected.

    Nitrous systems aren't a necessary component of your dental practice, but they can be beneficial. The use of nitrous oxide in your practice can be an important tool in offering your patients a relaxing experience. A relaxed patient will result in more successful procedures enhancing recall rates. The scavenging circuit plays a crucial role in the use of nitrous oxide, allowing you to safely deliver a controlled flow of nitrous oxide and oxygen to your patient while keeping staff protected.

  • FDA Announces Recall of the 980 Ventilator System

    Nellcor Puritan Bennett, 980 Ventilator System: Class I Recall: Software Issue May Stop Ventilator

    The FDA has notified health professionals and their medical care organizations of the Class 1 recall of the Puritan Bennett 980 Ventilator Systems with software versions below 2.8, with distribution dates March 3, 2014 through August 22, 2014 and serial numbers listed here. The recalled products have a software problem that causes the ventilator to stop working after the air and oxygen gas supply lines are disconnected and then reconnected, which could lead to serious health problems or death.

    RECOMMENDATION: Covidien sent an Urgent Field Corrective Action letter dated October 3, 2014 to its customers. A Covidien representative will update the software on the ventilators as soon as possible. To receive the software update, complete the acknowledgement and receipt form attached to the correction letter. Fax it to the Covidien contact found on the form.

    Customers may continue to use these ventilators until Covidien updates the software, as long as two gas sources are connected to the ventilator at all times. See the recall notice at the link below for other Covidien reminders and instructions from the Corrective Action letter.

    Read the MedWatch safety alert including a link to the Recall Notice at: http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm422362.htm

    Healthcare professionals and patients are encouraged to report adverse events or side effects related to the use of these products to the FDA's MedWatch Safety Information and Adverse Event Reporting Program:

    • Complete and submit the report Online: www.fda.gov/MedWatch/report.htm
    • Download form or call 1-800-332-1088 to request a reporting form, then complete and return to the address on the pre-addressed form, or submit by fax to 1-800-FDA-0178
  • Practice Tips #74: Infection Control (Part 1)

    Practice Tips this month is getting a little dressed up for Halloween (you will want to read until the end for an American Dental treat). We are going to tell you a few "tricks" to keep your vacuum facts straight.

    In the history of dental practices, infection control has had two major characters when it comes to chairside disposal: central vacuum canisters and debris baskets.

    The assistant’s instrumentation (particularly the high volume evacuator valve) is your first line of defense in infection control as it reduces contaminated aerosols which can spread blood borne pathogens which can contribute to cross-contamination.

    The high volume evacuator (HVE) and Saliva Ejector (SE) are often collectively referred to as the “assistant’s instrumentation” and will both connect to a collection canister or “chairside trap” as many refer to it.

    The collection canister serves two primary functions:
    One: Splits the main vacuum line from the central vacuum so you can have multiple vacuum valves in the operatory. Most canisters have 4 ports on the bottom, 2 for the HVE, one for the SE, and one to connect to the main line from the central vacuum. The different vacuum valves will reduce the expulsion of contaminated aerosols into the operatory, evacuate fluids from the oral cavity to improve visibility and allow bonding of various materials, and can even be used in conjunction with nitrous oxide to scavenge exhaled gases . In fact, the 2nd HVE port is often dedicated to a valve to use with your scavenger circuit.


    It is fairly common for the 2nd HVE port to be plugged with a port plug on new equipment. The port plug available from American Dental Accessories is different from most plugs in that it is tapered so it will fit inside the HVE port and outside the SE port. One plug can thus be used for either port. This plug is also made of a long lasting synthetic rubber rather than the thin plastic caps used by many equipment manufacturers.

    Two: Filter solids picked up by the HVE valve(s). As you can see in the photo below, the HVE ports poke up through the collection canister, so solid debris picked up will be caught in the basket. The SE normally only picks up liquids, so the SE port does not penetrate the basket.



    American Dental Accessories, Inc. carries 3 styles of collection canisters, referred to as types “A”, “B” and “C”:

    The Type “B” canister has a ½” outside diameter port to connect to the central vacuum line (the same size as the HVE ports). This is also the smallest canister with a basket (filter screen) that is only 1-7/8” in diameter. Because of the small size, the HVE ports are off center. This off-center design is unique to the type “B” canister. If using color-coded baskets, the baskets for a Type “B” canister are green.

    NOTE: HVE holes are off center due to the smaller size of the basket NOTE: HVE holes are off center due to the smaller size of the basket (1-7/8" diameter). Item #18-91.

    The type “A” and type “C” canisters both have a 5/8” port to connect to the line from the central vacuum (“drain port”) so they can offer superior suction. The overall size of the canister is bigger and they accept a basket that is 2-1/8” in diameter. The larger size allows placing the HVE ports along the diameter of the canister (and basket). There are other older designs that have this feature as well, however, so having ports along the diameter is not a clear indicator of which canister (or basket) one might have. If using color-coded baskets, the basket for the type “A” and “C” canisters is blue.

    NOTE: NOTE: HVE ports are centered due to the larger size of the basket (2-1/8" diameter). Item #18-90.

    The “A” and “C” canisters are distinguished from each other by the location of the drain port. The “A” canister has the 5/8” drain port on the bottom of the canister, the “C” canister has the port coming out of the side of the canister. The side drain allows the “C” canister to be used at the end of telescoping arms (#08-98 for example) or in other configurations that may not allow for a drain on the bottom. With a telescoping arm mount, the side port allows the drain line to feed through the arm aiding in asepsis and giving the unit clean aesthetics.

    NOTE: NOTE: There is a lack of a visible drain line in #08-98.

    When you look at vacuum canisters and debris baskets in such a way, they aren't quite the scary and characters for Halloween that we are used to. Just remember to watch out for the location of the HVE ports of the canister and the correlating baskets.

    We hope you liked our version of Halloween Practice Tips this month. We have a treat for you! By mentioning this blog post, you can buy one vacuum canister and receive a pkg. of 10 correlating baskets (#18-90 or #18-91) for free (call 800.331.7993 to order)! Check back next month for another installment.