Recently, an anonymous reader sent me a question asking about the differences between the instruments that dentists can use for cleanings.  It reads: For cleanings, my dentist uses a plaque scraper and the rotating buffer thing. Other dentists in the area advertise ultrasonic cleanings. What is an ultrasonic cleaning? Does it provide any additional advantage, or have any disadvantages?

First of all, there are two main techniques for removing plaque and tartar from your teeth – manual and ultrasonic.  A manual cleaning is done using hand instruments such as those pictured to the left.  An ultrasonic cleaning means that the dentist is using a special instrument that vibrates at a very high frequency to remove the plaque and tartar.  The ultrasonic instrument also sprays a stream of water toward your teeth.  Here are two examples of ultrasonic instruments: the Cavitron and the BlisSonic.

Regardless of the technique your dentist uses, the dentist will still use the rotating rubber cup with dental cleaning paste to smooth out and polish the teeth, as shown in the picture to the right.

Which Is Better, Ultrasonic or Hand Instrument Cleanings?

When I am preparing to clean a patient’s teeth, I consider how much plaque and calculus (calculus is the dental term for tartar, or plaque that has hardened onto the teeth.) that particular patient has on their teeth.  If they have a lot of plaque and tartar,  I will usually use an ultrasonic instrument to remove it.  This is mainly because the ultrasonic instrument can remove tartar much faster and easier than the hand instruments. However, after using the ultrasonic instrument, I always examine the teeth to make sure that I didn’t miss anything.  If tartar and plaque remain, I usually remove it with the hand instruments at that point.  I do this because it is easier to remove very small amounts of tartar with the hand instruments as it is easier to visualize the tartar with. This study suggests that ultrasonic instruments may be better because they have a steady flow of water that comes out of them and that can help to dislodge tartar that may have accumulated below the gumline. That study also talked about micro-ultrasonic instruments and how they are easier to maneuver below the gums due to their small size.  They can also reach down into the grooves better on tooth surfaces to remove more plaque. This study that compared the effectiveness of ultrasonic instruments and hand instruments concluded the following: [emphasis added]:

Evaluation of residual plaque and calculus after instrumentation with hand- and power-driven scalers showed sonic and ultrasonic scalers to be equivalent, and in some cases, superior to hand scaling. When modified ultrasonic inserts were compared with unmodified ultrasonic inserts and hand curets, the modified ultrasonic inserts produced smoother roots with the least amount of damage, better access to the bottom of the pocket, better calculus and plaque removal, less operator time, and less operator fatigue than did hand scaling…

Another thing that studies have looked at is how much good tooth structure the various instruments remove.  When a hygienist is cleaning your teeth and roots, they have to scrape hard to remove the plaque and tartar.  They unavoidably remove some good tooth structure when they do this. The final study we’ll take a look at involved the amount of healthy tooth structure ultrasonic instruments removed compared to conventional hand instruments.  Here’s what the researchers found:

Based on the results of these two comparative studies, the power-driven inserts or the various ultrasonic scalers tested did not remove more tooth substance than conventional hand instruments. They may thus be a useful alternative for the debridement of root surfaces.

They found that the ultrasonic scalers may not remove as much tooth structure as the regular hand instruments. In summary, the ultrasonic instruments do have many advantages when compared to the hand instruments.  When a patient has lots of plaque and tartar build-up, the ultrasonic instruments are great at quickly cleaning the teeth.  However, many dentists prefer to simply use hand instruments when there is only a small amount of tartar on the teeth.

Why Dentists Might Not Use Ultrasonic Instruments for Your Dental Cleaning

Many people go to the dentist twice a year to get cleanings.  When I see a patient with excellent oral hygiene and excellent teeth, it doesn’t make much sense to use an ultrasonic scaling instrument for their cleaning because there is such a minimal amount of calculus to remove.  Some patients have very little calculus because they floss regularly and brush with tartar-control toothpaste. When someone has just a small amount of calculus to clean off, I find it easier to just quickly use the hand instruments and then polish the teeth.  Using the ultrasonic instrument requires setting it up as well as sterilizing it afterward, so it makes more sense to quickly grab a tool to take care of a small problem. Perhaps a simple analogy will illustrate this point.  Suppose you use a drinking glass and need to wash it.  You could either wash it by hand or put it in the dishwasher – but you have no other dirty dishes to wash.  You would most likely wash it by hand rather than run it through a cycle in the dishwasher, right?  Well, for similar reasons, your dentist may elect to take care of small amounts of tartar with hand instruments.

A Video Showing an Ultrasonic Dental Cleaning

Here’s a video showing the difference between ultrasonic cleanings and hand instrumentation:

What Do You Think?

Have you had an ultrasonic cleaning?  Did your mouth feel cleaner afterwards?  Did you think it was more comfortable?  Some people prefer the ultrasonic cleaning, some don’t. If you have any questions or comments, feel free to leave them in the comments section below!