Image courtesy of Dentsply Sirona
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Chairside Impact: The benefits of ultrasonic instrumentation

Aug. 24, 2023
Dental hygienists need to understand their equipment's capabilities and limitations. When it comes to scaling, ultrasonics are the superior choice.

Over the years I have spoken with numerous clinicians on the topic of ultrasonic instrumentation. Dental hygienists report experiencing the benefits of ultrasonic technology such as ergonomics, speed, and comfortable patient experience. However, in the same conversations, they also comment about being unsure as to whether they are maximizing the capability of ultrasonic technology and describe using tips and inserts that have become ineffective. This perpetuates a heavy reliance on hand instruments and has been a roadblock for evolving ultrasonic knowledge and skills.

More "Chairside Impact":

From calculus to biofilm

Today, dental hygiene programs are shifting their focus from calculus to biofilm and the importance of its disruption and removal. It is the formation of oral bacterial biofilm and by-products that, if left undisrupted, alerts the body’s immune system to react and results in oral inflammation. If the reduction in bacterial load below the patient’s individual tolerance level of inflammation is not established, chronic oral inflammation results.1

In late 2020, at the University of Glasgow in Scotland, Johnston et al. did an in-vitro comparison of the effects of ultrasonic instrumentation versus hand instrumentation on biofilm. The investigators grew a multispecies periodontal biofilm in four separate identical wells with artificial saliva. One group was scaled using ultrasonic instrumentation, one was scaled with hand instrumentation, and two were controls. Ten strokes of each modality were applied to the specified well. Hand instrumentation wells had 10 strokes applied using a Gracey 1/2 curette. Ultrasonic wells had 10 strokes applied using a Cavitron 300 Ultrasonic Scaling System and a Cavitron 30K Slimline 10S ultrasonic insert.2 The results showed that when equal strokes were applied, the ultrasonic technology removed on average 50% more active biofilm compared to hand scaling.2 At one time, hand scaling was the gold standard, but randomized clinical trials have concluded that clinical outcomes using ultrasonic instrumentation are equal to hand scaling1 and often achieve these outcomes more quickly.3-5

Instrument quality matters

Time savings often correlates to equipment quality. Effective, efficient removal of calculus and biofilm with hand instruments is impacted by the selection of the best-suited tool, combined with the shape and sharpness of the working end/blade. Ultrasonic tips and inserts follow this same principle. Ultrasonic tip or insert wear is measured in millimeters. Dentsply Sirona has quantified wear results of Cavitron ultrasonic inserts and provides the following summary: “On average, using an ultrasonic insert with greater than 2 mm of wear results in a 30% increased scaling time and 40% more scaling force.”6

A 30% increase in scaling time speaks for itself. But what is the clinical implication of 40% more scaling force? An ultrasonic instrument with minimal to no wear works optimally with light lateral pressure. As an ultrasonic tip approaches 2 mm of wear, it begins to lose deposit removal effectiveness, and intuitively, clinicians apply more pressure and force. The application of more lateral pressure has the potential to cause discomfort. In my opinion, this should make practice owners take notice and acknowledge the repercussions of dental hygienists using worn-down ultrasonic instruments. After all, dentists are not drilling with worn-down burs.

It is important to understand the equipment we are using, its capabilities, and its limitations. Here I've included a few points relevant to what I have learned over the years about ultrasonic instrumentation. Practice satisfaction often stems from having the right equipment and instruments. It is up to us to educate practice owners by relaying the evidence on best practices that impact the quality of patient care. Additionally, practicing evidence-based dental hygiene includes the development of clinical expertise, and that is also up to us. I encourage you to explore the many facets of ultrasonic instrumentation and continue to improve your skills. The health of our patients depends on it! 

Editor's note: This article appeared in the August 2023 print edition of RDH magazine. Dental hygienists in North America are eligible for a complimentary print subscription. Sign up here.


  1. Suvan J, Leira Y, Moreno Sancho FM, Graziani F, Derks J, Tomasi C. Subgingival instrumentation for treatment of periodontitis. A systematic review. J Clin Periodontol. 2020 Jul;47:155-75.
  2. Johnston W, Rosier BT, Carda-Deiguez M, Al-Hebshi N, Chen T, Mira A, Culshaw S. Evaluating the microbial impact of hand and ultrasonic insturments in vitro and in vivo effects of instrumentation on in-vitro periodontitis biofilm. University of Glasgow, Glasgow, UK. FISABIO, Valencia, Spain. Komber School of Dentistry, Pennsylvania, USA. Forsyth Institute, Massacheusettes, USA. Presented at: IADR/AADR/CADR General Session. ID 3666. 2020; Washington, DC, USA.
  3. Johnston W, Paterson M, Piela K, Davison E, Simpson A, Goulding M, et al. The systemic inflammatory response following hand instrumentation versus ultrasonic instrumentation-A randomized controlled trial. J Clin Periodontol. 2020;47(9):1087-97.
  4. Hamm C, Dakin L, Lavoie D, Longo AB, Fritz P, Ward PE, editors. Timing of instrumentation use for non-surgical debridement using ultrasonics alone versus ultrasonics and hand instrumentation in generalized advanced periodontitis poster presented at: The Ninth Conference of European Federation of Periodontology EuroPerio June 2018; Amsterdam, NL.
  5. Tunkel J, Heinecke A, Flemming T. A systematic review of efficacy of machine-driven and manual subgingival debridement in the treatment of chronic periodontitis. J Clin Periodontol. 2002;29 (Suppl 3):72-81.
  6. Internal data on file. For more information, contact [email protected]
About the Author

Marianne Dryer, MEd, RDH

Marianne Dryer, MEd, RDH, is a dynamic speaker, educator, and consultant in curriculum development. She has lectured nationally and internationally on periodontal instrumentation with a focus on ultrasonic technique, risk assessment, infection prevention, and radiology technique. Her experience in dentistry spans more than 30 years. She is a graduate of Forsyth School for Dental Hygienists, Old Dominion University, and received her master’s in education from St.Joseph’s College of Maine. Contact her at [email protected] or through her website at