Good, good, good ... Good Vibrations!

by Kimberly R. Miller, RDH, BSDH, RDHMP

As summer gives way to fall, you may be hearing the final strains of that famous Beach Boys song, “Good Vibrations” Or, as a registered dental hygienist, you may be hearing the hum of your power scaler. Yep, I said hum! There's really nothing quite like the feel of those good vibrations in your hand, knowing you are blowing the smithereens out of the biofilm and all the while gently flushing the pocket. Wow, that's a lot of action! What is it Martha Stewart always says? “It's a Good Thing.” Yeah, I think that's it. And she would be right; power scaling is a good thing!

You know, it really doesn't matter what type of power scaler you prefer. You may be a magnetostrictive lover or a piezo fan. And since the kind of ultrasonic you drive is not nearly as important as the principles that drive you to use this technology, this article will overview the two technologies of power scaling while keeping the focus on the clinical benefits derived from incorporating those principles for successful implementation of power scaling into every dental hygiene visit.

Clinical benefits

In addition to the safe and efficient removal of hard and soft deposits, ultrasonic instruments also detoxify the areas being treated. The lavage or acoustic streaming that occurs simultaneously when treating with ultrasonic scalers causes a constant flushing action, removing loosened debris and bacterial biofilm from the area.1 Cavitation is created when the vibrating tip comes in contact with the fluid and forms millions of bubbles. When the bubbles implode, they produce shock waves or bursts of energy in the liquid, tearing apart the cell wall of the pathogens. This shifts the subgingival environment through elimination of the microbiology, essentially detoxifying the pocket.2

There is also some evidence that the heat generated during ultrasonic scaling with magnetostrictive in particular, may contribute to detoxifying the pocket. Additionally, cavitation combined with acoustic turbulence reaches root surfaces beyond where the tip has physical contact with the tooth. In other words, a halo effect occurs reaching additional pathogens through both of these mechanisms.3,4

Another distinct advantage of ultrasonics over hand scaling is the efficient removal of the smear layer. Scaling the root surface not only leaves a smear layer behind, but bacteria may be also “forced” into the tubules by the action of the scaler as it moves across the surface.8,9 The ultrasonic, by way of acoustic streaming, cavitation, and acoustic turbulence, literally “power washes” the root surface, eliminating the smear layer entirely.

Another great way to remove bio smear is with air polishing. In fact, there is a new piece of equipment just available in the United States from Electro Medical Systems (EMS) called Air–Flow Master Perio. This tabletop unit has both supragingival air polishing and the new technology of subgingival polishing capabilities. The subgingival air polishing removes biofilm to the base of the pocket and along the pocket wall through a specially designed, soft, single–use nozzle. The perio flow powder is formulated with glycine (no sodium) and is hydrophobic to ensure that no powder remains in the periodontal pocket. The studies indicate subgingival polishing is kinder to the root surface as well as the soft tissue.

There is a small percentage of patients with whom ultrasonics is contraindicated. Be sure you are familiar with these guidelines.

Principles for success

When we maintain our practice standards based on principles of care rather than specific procedures, techniques, or products, we remain focused on achieving the outcome and the best interests of our patients while using all methods and resources at our disposal. As Michael Miyasaki, DDS, Principle–Based Dentistry International, says, “As long as certain principles, which transcend a single technique or product, are being followed, success can be attained.”

There are four basic principles for successful integration of power scaling:

1) Always use the lowest possible stroke width to accomplish the task.

Many ultrasonic units sport a knob called “power.” In some cases, this knob may in fact adjust the frequency of the vibration, but often it actually adjusts the stroke width, which is the distance that the insert or tip travels in one stroke. For the magnetostrictive, you could imagine adjusting a windshield wiper blade for the width of the stroke across a windshield. For the piezo, think about the motion of a saw blade as it cuts through wood. The back and forth or reciprocating motion can be adjusted for the length of the stroke. Both of these technologies, when used at the wrong stroke width for the insert or tip, can feel like a mini jackhammer in the patient's mouth.5

2) Understand the way your equipment works, including maintenance.

Since pain or at least discomfort is one of the chief patient complaints regarding ultrasonic scaling, understanding the way your piece of equipment works when it comes to stroke width and power adjustment is critical. Consideration must also be given to the insert or tip you have selected. Often the power or stroke width, and sometimes water flow, need to be adjusted after you change the tip or insert, depending upon what that tip or insert is designed to do. Your insert or tip manufacturer should be able to provide you with some guidelines.

I mention maintenance since this is an often–overlooked detail. In order to deliver excellent care without interruption, the equipment we use must be kept in good repair. Many clinicians are unfamiliar with how to flush and drain their units at the end of the day. There is also a once–per–month flush recommendation for most units as well. Manufacturers tell me that the number one reason units come in for repair is reduced water supply. This is usually caused by ... you guessed it ... biofilm!

If you run any medicament through your unit, you will want to do a thorough flush each night and run the lines dry afterward since the medicament often builds up in the lines, sometimes even crystallizing.

3) Have a variety of good performing inserts or tips available.

Not only should you perform regular maintenance on your power scaler, but your inserts and tips must be checked monthly for efficiency. All brands of ultrasonic scalers have efficiency guides for their tips or inserts. Think of these tips or inserts like a block of burs on the crown prep tray. There are many choices in tips or inserts, and just like the burs, they are each designed to do something different. And when the bur will not cut anymore, what do you do with it? Yep, throw it away. In my experience, many hygienists not only limit themselves to two or three favorite tips or inserts, when in fact you can duplicate almost any hand instrument with a tip or insert these days, but we use them way past their prime. Consider that 1 mm of loss on an insert or tip means a decrease in efficiency by 25%. A 2 mm loss would translate to a 50% loss of efficiency and so on. Check your inserts and tips regularly to ensure successful treatment results.

While I know these inserts and tips can be costly and add up quickly, you may only need one or, in some cases, two of a more specialized type of insert or tip. Ask your supplier for an exhaustive list of the variety your brand carries. I think you will find some tips or inserts that you'll wonder how you ever lived without.

One final tip (no pun intended): All inserts have an O–ring just below the hub where the plastic meets the stacks. This O–ring needs to be inspected monthly, since leaking will occur at this point when the O–ring is bad or has a nick or chips out of it. And, we all know, patients never seem to appreciate that trickle of water down their necks.

4) Always use the correct insert or tip available to accomplish the task.

With the variety of tips and inserts available, we can work smarter, accomplishing more in the same period of time with much less trauma to the tissues and root surfaces than hand scaling.3 As a clinician, the best tip I was ever given was to look at these tips or inserts just like I would my Graceys and curettes. In other words, if I was going to remove chunks of calculus by hand, I would pick up a large bladed curette, not a mini or after–five Gracey. Likewise, if I were smoothing up the root, I would select a Gracey rather than a sickle scaler.

Ultrasonic tips and inserts follow the same theme. There are inserts and tips designed for smoothing up the root surface (slim lines and perio tips) and for removing heavy subgingival deposits or black tar stain. There are specific designs for removing those large sheets of calculus and for access into the furcations. Since the tips and inserts designed for heavy deposit removal are usually larger and have more bulk, they can be run at a wider stroke width and higher frequency, usually requiring more water flow. These inserts and tips have a specific design and would cause damage if I attempted root smoothing with them. The thinner slim line inserts and slim perio tips are designed with root smoothing, biofilm disruption, and light calculus removal in mind. These typically would be used at a shorter stroke width and therefore with less water. I've spoken with many a frustrated hygienist when it comes to calculus removal and slim lines. They are just not designed to remove large deposits, and instead, as the research has indicated, when they are used for that purpose it usually results in burnished calculus.

Order one new insert or tip every other month or every month if it's in your budget and branch out, trying some new ones. Some piezo brands offer only a few tip choices; however, EMS has some of the best selections available. Dentsply has a wide variety of inserts as does Hu–Friedy, although I have heard that using an off–brand insert may void your warranty. If you are looking for a hands–on course in power scaling, contact the JP Institute for locations and dates of classes.

Types of power scalers

• Magnetostrictive ultrasonic scaler is an instrument that uses a pulsing magnetic field applied to a metal “stack” that flexes to move the tip of the insert in an elliptical pattern. It generates heat and, therefore, requires fluid for cooling the handpiece and tissues.

• The inserts, as do the units, come in either 25k or 30k. That is 25 or 30 thousand cycles per second, which is really fast.
• Magnetostrictive inserts are active on all sides with the last 4.3 mm being the most effective portion of the insert.
• The inserts are fragile. They will bend if dropped on the tip. The stacks will bend and torque and make the insert unusable.
• Precaution during sterilization should be taken. These inserts should never go into the ultrasonic instrument bath. It will damage the stacks.
• Finally, it is best for the life of the insert if you are consistent with the type of sterilization you use. If you start with Statim, stay with it. If you start with autoclave, stick with it.

• Piezoelectric ultrasonic scaler is an instrument that uses pulsing voltage applied to ceramic crystals or discs that fly and move the tip in a reciprocating pattern. It generates heat and thus requires fluid for cooling the tissues.

• Piezo typically operates in the 40k to 60k per second range — really, really fast.
• Piezo tips are active only on the lateral sides (like a curette) with the last 2.4 mm being the most effective portion of the tip.
• These tips are durable, but can bend if dropped with the handpiece attached.
• Precaution during sterilization should be taken because these tips are little and often escape, kind of like the sock that escapes in the dryer.
• The type of sterilization does not affect the tips. However, you should have a consistent technique to sterilize the handpiece.

There is no doubt in my mind that power scaling is superior both in patient comfort and efficiency. I am not suggesting that hand instruments be put away, merely recommending that they become an adjunct to power scaling, instead of the other way around. Esther Wilkins, BS, RDH, DMD, suggests the 80/20 rule — that is, using ultrasonics 80% of the time and hand instruments 20%.6,7

Much research has been done comparing hand scaling to power scaling, and most of the evidence points to the latter being more effective. Additionally, the slim inserts and tips give the added advantage of access to furcations and deep, narrow pockets and boney defects, typically about a 1 mm advantage.1,2 With the consideration of acoustic turbulence reaching beyond the tip itself, the advantage may be even greater.

Regardless of which type of equipment you prefer, the principles for success and the clinical benefits for using ultrasonic instrumentation are very persuasive. Don't hesitate to branch out a bit and look into some of the less popular but very useful inserts and tips that are available to enhance your patient care and clinical results. I hope the next time you pick up your ultrasonic handpiece, the lyrics to “Good Vibrations” come to mind and you take a moment to congratulate yourself on providing the highest standard of care for your patients.

References

1. Walmsley AD, Laird WRE, Williams AR. Dental plaque removal by cavitational activity during ultrasonic scaling. Journal of Clinical Periodontology1988; 15:539–543.
2. Walmsley AD, Walsh TF, Laird WR, et al. Effects of cavitational activity on the root surface of teeth during ultrasonic scaling. Journal of Clinical Periodontology 1990; 17(5):306–312.
3. Young N, O'Hehir TE. Periodontal Debridement. In: Woodall IR: Comprehensive Dental Hygiene Care. St. Louis, Mosby–Year Book, Inc., 1993, pp. 533–570.
4. Hughes FJ, Smales FC. Attachment and orientation of human periodontal ligament fibroblasts to lipopolysaccharide–coated and pathologically altered cementum in vitro. European Journal of Prosthodontic and Restorative Dentistry1992; 2:63–68.
5. Chapple ILC, Walmsley AD, Saxby MS, et al. Effect of instrument power setting during ultrasonic scaling upon treatment outcome. Journal of Periodontology 1995; 66(9):756–760.
6. Drisko CL. Scaling and root planing without over instrumentation: Hand vs. power–driven scalers. Current Opinion in Periodontology 1993; 77–88.
7. Wilkins E. Clinical Practice of the Dental Hygienist, 9th ed. Malvern, PA, Williams and Wilkins, 2004; 661–670.
8. Drisko C. Dentine hypersensitivity — dental hygiene and periodontal considerations. International Dental Journal 2002; 52:385–393.
9. Adriaens PA, DeBoever JA, Loesche WJ. Bacterial invasion in root cementum and radicular dentin of periodontally diseased teeth in humans. A reservoir of periodontopathic bacteria. JPeriodontal 1988; 59:220230.

About the Author

Kimberly R. Miller, RDH, BSDH, RDHMP, is a partner of the JP Institute and a cofounder of PerioFrogz. A graduate of Loma Linda University in 1981, she received a bachelor's degree in dental hygiene.

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Precautions

• Use prerinse with chlorhexidine to reduce aerosol contaminants
• Esthetic dentistry — precautions at the margins of composite and porcelain
• Demineralized tooth surfaces

Contraindications

• Nonshielded pacemakers
  • Consult with physician/call number on implant ID card

• Implanted defibrillators
  • Consult with physician/potential negative effects
• Problems swallowing
• Infectious or communicable diseases — due to aerosols
• Children with deciduous or newly erupted teeth
  • Only use for gross calculus removal with short strokes — minimal use
• Respiratory risk
  • Due to aerosols aspirated into lungs
• Susceptibility to infection — immunocompromised patients