Send an e-mail to info@amerdental.com for full details including course fees.

Can’t see the video? You can also view this video on Youtube.

Over the past two decades, much has been written about dental unit water lines (DUWL) and their impact on infection control. Way back in 1992 the American Dental Association issued a standard to help address water quality issues. Later on, they also set a goal for dental equipment manufacturers to improve the quality of water delivered by the dental unit. The ADA wanted DUWL to have less than 200 bacteria colony forming units (CFU) per milliliter of water (this is the standard for drinking water). On testing, many dental units were found to have 5 or even 10 times of this level.

Most typical household (and dental office) plumbing consists of 3/4″ or 1/2″ inside diameter pipes. This provides a fairly robust volume of water flow, particularly relative to the surface area on the inside of the pipes. Most dental units have water lines that are mostly either 1/8″ or even 1/16″ inside diameter. This provides a very low volume of water flow, particularly when compared to the surface area on the inside of the hose.  On top of that, dental units sit idle for long periods of time (overnights and on weekends) so the water is stagnant (zero flow) during this time. In addition, many dental devices (e.g. handpieces and ultrasonic scalers) generate tremendous amounts of heat. These conditions are ideal for bacterial growth.

A recent study conducted at Purdue University (http://www.pnas.org/content/110/11/4345.full?sid=8ae98062-01f7-4944-add6-e49a56c403df) found that biofilm can form and grows at a tremendous rate. Not only does the bacteria grow at a tremendous rate, but the biofilm growth will form a web which will trap more bacteria increasing the size of the colony at an exponential rate. In fact, the biofilm mass can increase in size so quickly that the study found the lines could be completely clogged with biofilm in as little as 55 hours!

While reducing bacteria is extremely important in your infection control efforts, just reducing the likelihood of clogging is a tremendous benefit of using self-contained systems.

By using a self-contained water system, not only are you able to control the bacterial levels of the water as it enters your unit, you are also able to take steps to counter the growth of bacteria in the lines.

Self-contained water systems are “powered” by the office compressed air. This means air flows into the reservoir of the system to force the water out. This means air flows into the reservoir of the system to force the water out. Since air is flowing into the water system, you can use this air to dry the lines at the end of every day so you don’t have standing water in the system for prolonged periods. Many water systems will have a valve incorporated to flush the lines with air. Of course, you can also simply install an empty bottle and turn the unit on to perform an air purge as well.

There are many chemical treatments that can be added to your bottles to kill bacteria or inhibit bacterial growth as well. Some of these are used periodically (daily, weekly, etc.) and some are introduced constantly with the unit water.

As we saw last month, installing self-contained is a simple and straight-forward process. Using self-contained water will save money, improve the quality of your unit water (and thus enhance your efforts in infection control), and reduce down time and repairs (by reducing clogging).

Save big with our Spring Specials! Hot deals on gloves, diamonds, carbides, needles, materials, cups, & masks. Prices valid through 6/30/13.

This Beaverstate Control Head is right at home

The new Beaverstate unit features smooth lines for easy cleaning. We also configured the unit with fibre optics, a self-contained water system, and assistant’s vacuum valves (HVE and SE).

By using a self-contained water system the doctor can control his water quality. Using the system as the only source of water also saved money as he didn’t need to purchase a water master valve.

This doctor shows that you don’t need to invest in a whole operatory of equipment to update your office. With American Dental Accessories, Inc. you can make small changes to individual components and still improve your practice.

Got a project you’d like to share? How about a unit you’ve installed? Maybe just a couple photos of an op freshened up by simply installing new tubing? Tells us about it! Send your photos and stories toDIYDENTIST@amerdental.com and receive $25 American Dental Reward Dollars*.

Can’t see the video? You can also view this video on our blog or Youtube.

This month, we’re posting a copy of the patient instructions that come with our denture care kits. These instructions tell patients how to properly care for their appliance and keep it clean.





Instructions

Your dentures are fragile, handle them with care. While handling the denture, stand over a folded towel or hold them over a sink filled with water so if they are dropped, they will not be damaged.

Brush and rinse your dentures daily. A soft bristle brush designed for cleaning dentures is recommended. Hard bristle brushes can damage the plastic or bend metal parts. Hand soap, mild dish soap, and specifically designed denture cleaners are recommended. An ultrasonic cleaner may also be used.

When not worn, keep your dentures moist so that they do not dry out and lose their shape. You may keep them immersed in a denture cleanser soaking solution or water. Do not use hot water, as this can cause the denture to warp. If your denture has metal parts that may tarnish, check with your dentist on proper storage methods.

NEVER attempt to adjust or repair your dentures, as this may cause permanent damage to the denture. In the event that the denture breaks, cracks, chips, or a tooth comes loose, contact your dentist. Most repairs can be made the same day.





You can download a pdf version of these instructions on our web site or use the “Print Friendly” button below to easily print this article. Feel free to print it out to give to your patients.

Our denture care kits not only include these instructions, but also a denture case, cleaning brush, and cleaning tablets for you to give to your patients with their new appliance. With our kits, you can be assured your patients will have the tools and information to properly care for their new appliance.

Compressors use electricity, the harder they work the more electricity you will use as well. In addition to routine maintenance, how else can you reduce the load of your compressor and save electricity?

Leaks

Air leaks mean your compressor runs more frequently (in extreme cases constantly) which can not only lead to a shorter compressor life but a tremendous waste of power. A telltale hiss will usually be your first sign of an air leak- but how do you find the leak so you can correct it? A simple method is to coat suspect joints or fittings with soapy water. Mix a solution of about 25% dish soap and 75% water and brush it onto suspect areas. If there is an air leak, the solution will bubble.

Worn or cracked hoses should be replaced. If the leak is near one end, you may be able to trim the hose and re-attach with a fresh end.

You should use Teflon tape where possible for threaded fittings although Loctite (usually the yellow or blue formula) will work well also. Barb threads should be sealed with a washer gasket.

Worn o’rings can also result in leaks. Lubricate o’rings regularly with silicone lubricant to keep them supple and sealing well. Of course sometimes replacement is in order as well. Keep spares on hand.

Clogs

Clogged lines can also put strain on your compressor. A classic symptom of a clog is rapidly dropping pressure.

It’s common to have good pressure but as soon as you use your handpiece the pressure rapidly drops off. You hang your handpiece up and a minute later you again have good pressure but it again drops off quickly. This is classic obstruction behavior.

The line is obstructed so you have minimal air flow. While not in use, the “dribble” of air builds up into solid line pressure, but as soon as you begin to use it the pressure drops off as the obstruction prevents maintaining line pressure for a prolonged period.

To find the clog, you need to trace the line backwards from the point you’ve noticed a performance drop until you find solid consistent line pressure. The clog will usually be at the next junction AFTER you’ve found good pressure again.

Make certain to check your filters regularly (we recommend every month) to help prevent clogs. You should have filters in your junction box.

While you’re in your junction box, you should also double check your pressure. Most units recommend running at 80 psi of air. You should have a regulator with a gauge on it (similar to that pictured above) to indicate what your air pressure is. Excessive pressure can cause your compressor to run too frequently as well. Verify correct pressure on the gauge and then hold down the air button on your syringe and watch the gauge. Does the pressure hold steady? Does it decrease? If the pressure drops off check for clogs (as above) but also check your compressor. The regulator in the units can only step the pressure down. It’s very important that you have your regulators set to a pressure less than the output of your compressor; otherwise they may not actually be controlling pressure at all. To provide a steady 80 psi in the ops, your compressor should be set to 90-100 psi. Of course, you also don’t want your compressor set too high, so keep it within this range (barring special high-pressure equipment). If your compressor is set lower than 90-100psi, you will almost certainly fail to achieve proper pressure in your ops and can encounter a host of problems, like cross over.

Many things in the dental unit are air activated (including your water) so it’s also important that your air pressure isn’t too low (actually, this is something we see more often than excessive pressure) but it’s good to avoid excess; “more” isn’t always better.

Of course, as with most things try to make sure to turn units off when not in use to conserve power. If an op will be out of use for more than an hour, shut the unit off using the master toggle on the front of the unit. This will shut all air & water into the operatory off.

Moisture

Moisture can have a horrendous effect on your compressor. Moisture can lead to corrosion of components, loss of pressure, and even cross-over affecting other equipment downstream. Make certain you have proper filtration and drying systems in place.

Many filtration and drying systems will have moisture indicators to show if it’s time to replace elements. Check these indicators regularly and keep spare filter elements/drying media on hand.

After changing filters, it’s also a good idea to check indicators again to verify that not excess moisture is not in the system from some other source.

Many compressors will also have a tank drain, make sure this is operating properly and is drained every day.

Of course, it’s also important that you get the correct compressor for your needs in the first place. A compressor that is too small will be working overtime and is likely to fail quite early. When purchasing a compressor, always pay attention to the user ratings. Dental compressors are rated for a number of “users”. This number is equal to the number of dentists that can be using a unit powered by the compressor at once. Hygienists are considered 1/2 user for purposes of compressor capacity. So, if you have a compressor rated for 3 users, you can have one dentist and 4 hygienists (1 + 4 x 1/2), or 2 dentists and 2 hygienists, or any of a number of other permutations.

Conclusion

The compressor is the heart of the dental practice, getting the most out of it will not only save by helping to minimize down time, but can help you save electricity and keep it beating for the life of the practice.  So be sure to keep up with routine maintenance, watch your pressure at the compressor and in the ops, listen for leaks and make sure your air is dry.

Can’t see the video? You can also view this video on our blog or Youtube.

Save big with our End-of-Year Specials! Hot deals on gloves, diamonds, carbides, & dental equipment. Prices valid through 12/31/12.

What if you’ve got cross over in more than one room? Is it possible that one room is affecting the others? Yes, cross over can work through the lines from one room to the entire office. In fact, you can even get air in your pipes (if you’ve got air in the water line) so pipes will rattle, squeak, or groan when any source of water is used (such as a faucet or even a toilet). Of course, you can also get failed valves in multiple rooms at once.

How do you determine which room is to blame, or even tell if it’s one or more?

Since we left off last month in the junction box, let’s continue there.

In addition to your master valves, you should also have manual shut offs in your junction box. Normally, the master valves are attached directly to the manual shut-offs. The manual shut-offs have a knob that you can turn to physically stop the flow of air and water. Use them to shut both air and water off in an affected room. Start in the room closest to the compressor.

A Typical Manual Shut-off valve

Once the manual shut-offs are closed, depress the buttons on your air/water syringe until all flow ceases. Next turn the AIR manual valve back on, but LEAVE THE WATER OFF. Put your syringe tip into a cup of water and hit the WATER button of the syringe. If you have bubbles, you have cross over in that room. If you had been experiencing water in the air line, you’ll want to hold the syringe button down for at least one full minute as it may take some time for the air to work its way through the lines. If you don’t have bubbles, that room is probably fine. Turn both air and water off with the manual shut-offs and proceed to the next room and repeat this test. It’s important that you turn both valves off before checking the next room to keep any cross-over that might be occurring in this room from affecting others.

Where else can you get cross over? Any other air-activated water valve in the unit.

If you have cuspidors with timers for the bowl rinse or cup filler functions, the timers are air activated and could be a source of cross over. As cuspidors typically have large lines attached, these can affect the whole office more readily. If you’ve got squeaking pipes, your cuspidor may be a more likely culprit.

Just like master valves, timer valves can vary in design but will be mounted inside some sort of “box” or “utility center” directly below the cuspidor. The timers often have a similar appearance to master valves and will have some sort of knob to adjust the timing.

The arrow indicates one of the timer valves on this cuspidor manifold. Note the square portion of the valve with a metal cover, just as we saw last month on the master valves. This manifold also has on/off valves at each end which could have failed as well.

Other possible sources of cross over are the water relay valve or even the handpiece block.

Normally, a failure in the water relay valve will result in trouble with handpiece water long before you experience cross over, so this is not very likely unless you’ve also had trouble with your handpiece water coolant (dripping, coming out of the wrong handpiece, or other issues). Depending on the design of valve, usually the water relay just needs to be replaced as most are not readily serviceable.

Last of all is the handpiece block. There are many designs of block, so this can be more difficult to check, but often a diaphragm will be readily apparent when you inspect the block (such as in the block pictured below, as used in a Beaverstate delivery system). You can clearly see the seam between the two layers of brass in the photo. This is where the diaphragm is.

A Beaverstate style handpiece block

In many models of units, water does not actually enter the handpiece block, so you would not get cross over here. Always be sure to verify the configuration of your unit before checking the block.

If you have quick disconnect handpieces, you can also get cross over in the coupler. Normally cross over here would only be seen in the handpieces. In this case, you may see water dripping out of the unit. This is actually from water coming out the exhaust line (which often empties into the unit). If you see water dripping out of the unit (or it’s getting into your turbines) change the o’rings on your quick disconnect.

As you can see, there are a number of possible sources of cross-over in the dental office. To help you diagnose, we’ve provided a handy checklist below:

Possible Sources of Cross-over

• Compressor
• Air/water syringe
• Master Valves
• Cuspidor timer blocks (if present)
• Handpiece block
• Handpiece coupler (if a quick disconnect)
• Any other air activated valves (e.g. water relay)

As mentioned above, check one room at a time to verify where cross-over is occurring then check the valves within each room to determine the precise source.

Save big with our End-of-Year Specials! Hot deals on gloves, diamonds, carbides, & dental equipment. Prices valid through 12/31/12.