Just like Rosa Parks

April 1, 2006
Most of us are familiar with Rosa Parks. Many years ago, Rosa was asked to give up her seat on a bus for a white man and she refused to do so.

Most of us are familiar with Rosa Parks. Many years ago, Rosa was asked to give up her seat on a bus for a white man and she refused to do so. The white bus driver warned her that she would be arrested if she did not comply. She dug in her heels and replied, “You may go on and do so.” Rosa Parks did not get on the bus to be arrested; she got on the bus to go home.

In early January, I flew to Houston for a couple of days. I had registered for Anne Guignon’s hands-on ultrasonics course, and I was excited about getting to know her better. Little did I know that the course would turn out to be one of those life-changing experiences. Like Rosa Parks, Anne digs in her heels and speaks the truth. You can’t help but admire her style.

Anne’s course is conducted in a dental office in a Houston suburb where she practices regularly. We were a small group of course participants (four of us altogether) and the intimacy had its advantages. Shortly after I arrived and settled into my hotel room, the group met for dinner at a local restaurant. We sat around a table and introduced ourselves. We also shared with each other our reasons for registering and what we hoped to learn.

While sitting at the table, I looked up and noticed that I was sitting below a huge mounted buffalo. My thoughts wandered for a moment and I recalled what I had once read about buffalo. They look lazy and slow, but this is a fallacy. In fact, they can outrun a horse, and I quickly learned after spending one evening with Anne that she could probably even outrun a buffalo!

After a wonderful evening, we met the following morning in the reception area of the office where Anne practices. Anne showed us all the latest and greatest hygiene equipment. During the afternoon, we practiced on each other and on volunteer clients. Also, in the morning session, Anne was teacher extraordinaire and exposed us to ultrasonics using various teaching strategies.

Like Anne, I am a huge fan of ultrasonic instrumentation. Over the years, I have found myself using fewer hand instruments during debridement and maintenance procedures. If I use hand instruments in addition to ultrasonics, I prefer the hand instruments that maintain a sharp edge longer.

Don’t get me wrong; I know how to sharpen hand instruments but appointment time constraints, concerns about infection control while sharpening, and risk of repetitive stress injury have led me to the newer curettes that require less sharpening and fewer strokes to get the job done.

Biofilm removal and ultrasonics

Effective debridement of the subgingival environment mandates the use of subgingival instruments to remove biofilm on as many surfaces as possible. When scaling around furcations and in narrow and deep defects, a thin, probe-like microultrasonic insert is more desirable than a hand curette because it is thinner and perhaps even more predictable. Not only are there tips that are the diameter of a periodontal probe, there are also magnetostrictive and piezoelectric ones that rival the diameter of an explorer.

Based on research conducted in various biofilm laboratories such as the Center for Biofilm Engineering at Montana State University-Bozeman, antimicrobial agents are thought to be relatively ineffective because they are depleted to ineffectual levels before reaching subgingival biofilm.1 Antimicrobials may be carried to the surface of the biofilm but are not effectively transported to its depth. Even if an antimicrobial agent does permeate the biofilm, sometimes the microorganisms live in a state that reduces their susceptibility.1

Therefore, what can be more important than mechanically removing as much biofilm as possible? What better tool to accomplish this task than the appropriate ultrasonic insert?

Much of the research on ultrasonics has come from the University of Birmingham in the United Kingdom. At a medium power setting, researchers have found that water-cooled tips remove more biofilm on extracted teeth than ultrasonic tips without water, and that biofilm removal is influenced by the type of scaling tip used, its orientation to the tooth surface, and its displacement amplitude.

In addition, acoustic mainstreaming (cavitation) occurs around ultrasonic scalers. This, too, depends on displacement amplitude, tip orientation, and the presence of a water medium.2 Hand instruments do not disrupt subgingival biofilms the way ultrasonic instruments do. Anne uses creative and humorous

analogies when talking about acoustic mainstreaming. She compares biofilm to a blob of Jell-O and uses grapes to represent tiny water bubbles. During cavitation, bubbles oscillate in the ultrasonic waves and become larger and larger until they collapse in a violent implosion.

Clients prefer ultrasonics

Did you know that clients prefer ultrasonic instrumentation over hand instrumentation? Research conducted by Croft, et al. showed that most clients actually preferred manually tuned ultrasonic scaling with specialized inserts without the supplemental use of hand instruments.3 In addition, they found ultrasonic instrumentation to be less messy with the end result being a “cleaner feeling.” While in Houston, I had the opportunity to try a high-end manually tuned ultrasonic unit and not only were the inserts ultrathin and very comfortable for the client, the unit was also very easy to operate.

Ultrasonic equipment is either manually or automatically tuned. Proponents of manually tuned equipment insist that the clinician has more flexibility in adjusting power levels with better control over power spray. On the other hand, proponents of automatically tuned units are happy with the convenience. Clinicians who enjoy piezoelectric units will find that these units are only available with automatic tuning. Whichever equipment a clinician prefers, one very important consideration is the purchase of precision thin (or microultrasonic) inserts for biofilm removal, especially in deep, narrow pockets and furcations.

Anne Guignon is one of those hygienists and public speakers whom I refer to as an ergonomic super-diva. She lectures and writes incessantly on the subject of ergonomics and instrumentation. She stresses that wrist, hand, and arm discomfort is minimized during ultrasonic instrumentation because very little pressure is applied to the handpiece while working. She recommends placing the handpiece cord around the operator’s neck and always gripping the handpiece very lightly.

One of the course participants, Dee Williams, RDH, made a significant point: “We (hygienists) need to be responsible for ourselves and sometimes that means purchasing our own equipment. ... It’s a shame that we have to spend our own hard-earned money, but sometimes we need to do so to protect our careers.”

Dee’s husband is a gem of a dentist who believes very strongly in investing in the right hygiene equipment to prevent repetitive stress injuries. In addition, intraoral fulcrums are rarely needed when instrumenting ultrasonically, which is a relief to many clinicians who never quite mastered intraoral fulcrums while in school! (I mastered intraoral fulcrums because I had no choice, and I am happy that my clinical instructors insisted on them during hand instrumentation.)

There is so much to write about on the topic of ultrasonic instrumentation that I can only brush the surface (no pun intended). Hygienists should try the various piezoelectric or magnetostrictive units on the market while attending a dental or hygiene convention. Remember to pay close attention to the newer, microultrasonic inserts, especially the ultra-thin ones that look probe-like.

Here’s an advantage to ultrasonic instrumentation that many instructors rarely talk about. When appropriately used, ultrasonic scalers may cause less root damage and/or excessive cementum removal and they also provide greater access to furcations and to the apical third of the pocket.4 Biofilm prefers rough surfaces like pits and root irregularities, and root surfaces are more heavily colonized than other parts of the tooth.5

One of my pet peeves when I do temp work in local dental practices is the bad habit some hygienists have of not replacing worn ultrasonic inserts. Some of the inserts I have scooped out of drawers have tips that remind me of nails chewed down to the nub. When I find them, I sometimes throw them in the trash (but don’t tell anyone!) because they are so badly altered that scaling efficiency is practically zero.

Like Anne, I understand that many hygienists were not adequately trained in ultrasonic instrumentation. It is never too late! Once you convert, you will never look back, and your instrumentation skills will soar to new heights. Don’t waste your time hand scaling plaque/biofilm during an adult prophy when a microultrasonic insert will not only remove the deposits more efficiently but flush them away. You can re-train even your toughest clients to accept ultrasonic instrumentation.

The key to making the switch has to come from within you! I made the conversion many years ago, and my clients tell me that they no longer dread the maintenance appointment and feel much cleaner as a result. The next time you seat a client and unwrap your bagged instruments, don’t scare your clients by unwrapping a five-pound wad of hand curettes along with a sharpening stone. Instead, carefully unwrap your ultrasonic insert(s) and a few specific hand instruments instead!

What is it about Anne that makes her so unique and inspirational at the same time? Like Rosa Parks years ago, Anne is completely honest and determined, and you feel that you can trust her from the very moment you are introduced to her. Anne is colorful, inspirational, sharp, and generous to a fault. What more can you ask for in a teacher, and how lucky we are to have her as part of our treasured RDH community.

Author’s note: I give credit to Elizabeth Nies, RDH, from Boise, Idaho, for coming up with the inspirational comparison between Anne Guignon and Rosa Parks.


1. Montana State University. Center for Biofilm Engineering. Biofilm basics. www.erc.montana.edu.Accessed: 2/1/06.

2. Khambay BS and Walmsley AD. Acoustic mainstreaming: detection and measurement around ultrasonic scalers. J of Periodontol 1999; 70(6): 626-636.

3. Croft LK et al. Patient preference for ultrasonic or hand instruments in periodontal maintenance. Int J of Perioontics and Restorative Dent 2003; 23(6): 567-573.

4. Kwan JY. Enhanced periodontal debridement with the use of microultrasonic periodontal endoscopy. CDA Journal 2005; 33(3): 241-248.

5. Fejerskov O NB. Scanning electron microscopy of early microbial colonization of human enamel and root surfaces in vivo. Scand J Dent Res 1987; 4: 287-296.