Bad Breath Examination as a General Dentist Using a Halimeter


Originally published in the Dentaltown blogs, January 20, 2016

Torunn Birkeland Bakken    [Nordmo Tannlegesenter, Kristiansand, Norway
  She also runs the   “Ask The Dentist”  section of]

I’m a general dentist working in a 10-dentist clinic in Kristiansand in southern Norway. Since 2014, I have regularly used a Halimeter to detect and diagnose halitosis. I’d like to share with you how we use this in our clinic to help patients struggling with halitosis.

The Halimeter is an instrument with a special gas sensor that detects a range of compounds: hydrogen sulfide, methyl mercaptan, other thiols, and dimethyl sulfide. These are referred to as volatile sulfur compounds (VSC) and are well documented to be the main malodorants when it comes to halitosis.

The Halimeter I use is connected to my computer, and with the Haligram software, I can easily monitor on my screen what the gas sensor detects. This is beneficial when comparing results as well as for updating a patient’s file.


How Does the Halimeter Work?

The Halimeter is very easy to use, is highly accepted by patients, and does not cause any discomfort during testing. All the patient has to do is keep a special straw (disposable, for hygiene reasons) inside the mouth for a couple of minutes. Usually, I start by placing the straw on the patient’s tongue, carefully adjusting it to avoid interference with the tongue’s anatomy. The straw should lie on the top and back of the tongue in order to detect any compounds arising from the surface and should not point down as this will block any detection of gas in the area. After the initial detection on the tongue, I also move the straw to other areas in the oral cavity where I suspect foul smells may originate. This could be under a bridge, close to a cavitated tooth, or between teeth.

Often the patient has a sensation that the malodor comes from a certain tooth or area, so I also test these areas. After a few minutes, the detection is done, and I discuss the result with the patient.

The Halimeter enables measurements of bad breath to be quantified in parts per billion (ppb). As a standard, I would say that a result under 200 is quite acceptable and is regarded as normal. Obviously, it is “better” to have a result of 100 ppb than 200 ppb. Generally, I would say the lower the level, the fresher the breath. I have had patients with ranges from 50 ppb to 600 ppb. The person with 600 ppb had a very bad malodor, while the person with 50 ppb did not smell bad at all. However, many different variables can affect the result.


Examination Workflow

As the first clinic in Norway to offer this service (and the only one, to my knowledge), we have patients coming from all parts of southern Norway. All of them have the same problem: They are extremely bothered by bad breath. Some of them have true halitosis as the Halimeter detects very high levels of VSC. However, others with very low levels of VSC may start to realize that they suffer from halitophobia, which is the fear of having bad breath. It is also important to keep in mind that the Halimeter detects only VSC, and bad breath can be caused by other substances in the oral cavity that the Halimeter does not detect.

So what do I do when a patient calls and wants an appointment due to his bad breath? I start by informing the patient how we do the examination and suggesting what he should think of before coming to the appointment.

First of all, the examination should be done in the morning. This enables us to detect as much as possible without the interference of the patient’s habits, such as eating, drinking (coffee), smoking, etc. We also know that the morning breath is the “worst”, so we want to know what the breath is like when it is at its worst for the patient. In the morning, the patient comes to the clinic without having had anything in the mouth since he or she got up out of bed: no eating; no drinking; no coffee; no cigarettes; and of course, no brushing teeth or using any mouthwash.

When the patient arrives, he fills out a two-page form with a lot of questions concerning general health (such as diseases, use of medications, etc.); specific oral health (dental hygiene routines, dental diseases or problems); eating habits (especially concerning foods that we know will cause bad breath); and smoking habits. He is also asked whether somebody has told him that he has bad breath or whether he feels that the bad breath makes his social life difficult, and so on. This extensive “interview” serves as a basis for the examination. From there, I do the Halimeter test first. For two minutes or so, the patient has the special straw in his mouth. This detects oral gas and shows the amount of VSC on the screen.

After this, the patient has his bitewings and OPG done in order to determine whether his halitosis appears from obvious oral pathology, such as a tooth with pericoronitis, a root with apical periodontitis, or general marginal periodontitis. Next, I do a full examination of the patient’s oral cavity and teeth. During the examination, I am also be able to smell typical bad breath odor. This is in fact an important diagnostic tool. I believe that we dentists have quite good noses when it comes to detecting typical bad breath! Concerning the clinical examination, I first look at the tongue and examine the surface of it. Does it have plaque? If it does, is it white, yellow, or brown?

Following this, I look elsewhere in the mouth to see if there are lesions of any kind. The throat is always of interest as I question whether the patient suffers from chronic tonsillitis with the formation of crypts or white or yellow plaque that can give a quite annoying foetor ex ore. It is also very important to examine the gingiva as gingivitis or periodontitis is by far the most common reason for halitosis. Patients with chronic marginal periodontitis will often tend to suffer from bad breath.

Finally, I examine the teeth to see if there are any caries lesions, cavities, or other infections or lesions that might give bad breath. All of these examinations will give me enough information to decide whether or not the patient suffers from true halitosis.


Building Trust and Follow-Up

In working with patients having issues with halitosis, I am always very careful when talking about the emotional involvement. I use a well-established protocol so that the patient knows that he and his problem are treated seriously.

I always offer a follow-up appointment. Why do I do this? Well, first of all, I believe that this may be motivational for the patient. When he knows that he has an appointment again in a couple of weeks, this gives him a chance to do something about his oral hygiene habits, eating habits, smoking, etc. I will also check to see if any gingivitis is healed, whether the tongue has been scraped properly, whether the pericoronitis is under control, whether there is a lot of newly-developed calculus, and so on. Most patients are very happy to come back and appreciate their problem with halitosis being taken seriously.

In my experience, it is quite easy to motivate patients with bad breath. They really do suffer and often feel that their breath disrupts their social life. Most of them are willing to make extensive changes when it comes to oral hygiene/care. Using a tongue scraper, interdental brushes, and mouthwash with chlorhexidine and zinc usually help a lot. They may also need to consider whether or not their diet could be modified.