Clinical Research Associates

Intro & Methods Section

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Oral malodor is a condition that is common among people and unresolved by dentists. Many methods have been developed for detection and many products are being manufactured daily to eliminate oral malodor. This embarrassing problem has created a lucrative business in 1999. DETECTION & ELIMINATION OF ORAL MALODOR

1. What are the best methods for analyzing the gases that cause oral malodor?

2. Which treatments significantly reduce malodor for long periods of time?

3. Which treatments significantly reduce H₂S immediately after use?

Four different techniques were used to determine the level of oral malodor: Halimeter, Jerome 631-X, Solid Phase Micro Extraction Gas Chromatography Mass Spectroscopy (SPME GCMS), and the human nose (organoleptic judge).

The Halimeter is a portable gas monitor using an electro-chemical sensor to detect volatile sulfur compounds (VSC). Patients place a sampling tube deep into their mouth and a built in vacuum takes an air sample. This instrument gives the dentist a reading in ppb and the manufacturer supplies a clinical interpretation in terms of halitosis level (i.e. 80-160 ppb = normal breath, 160-250 ppb = offensive at intimate distances, 250+ ppb = offensive a larger distances or Halitosis).

The Jerome 631-X is a portable gas monitor using a gold film sensor to detect H₂S only. Like the Halimeter, the patient places the sampling tube deep into their mouth and a built in vacuum takes an air sample. This instrument displays H₂S readings in ppm and comes with a certified H₂S standard for daily calibrations.

Solid Phase Micro Extraction is a sampling technique using a 100 m m polydimethylsiloxane fiber which absorbs gas molecules from its environment. This technique was used by piercing the septum of a bottle containing the mass of a tongue scraping. The fiber is then exposed to the gases produced by the tongue scraping. The analysis is performed by inserting the fiber into a GCMS.

Two judges were selected based on their consistently high scores on odor sensitivity tests. Patients with diagnosed halitosis kept their mouths closed for 2 min. to allow oral gases to concentrate. Using a wafting technique 1 inch from the oral cavity, the blinded organoleptic judges rated odor according to the following scale: 0 = No odor, 1 = slight odor, 2 = definite odor but mild, 3 = significant odor, 4 = strong odor, & 5 = overwhelming odor.

Halimeter readings were significantly influenced by other oral gases (i.e. chewing gum, strong mouthrinse odors, and alcohol) which resulted in false VSC readings. Because of these inconsistencies the Halimeter was excluded as a detection device.

Organoleptic judges were highly consistent in ranking oral malodor. Judges correlated significantly with R = 0.81 and n = 316.

Public advertisements were posted to attract people with a perceived bad breath problem. 130 people around the Provo, Utah community volunteered to be screened. Screening consisted of a professional oral examination, blinded organoleptic measurements by two judges, and Halimeter measurements. 21 people were selected and diagnosed with extreme halitosis.

The following 10 treatments were tested to compare bad breath control capabilities:

Oxygene w/zinc: CLO₂ & Zinc Acetate
Tooth & Gum Tonic: Essential Oils
Colgate Professional Breath Rinse: Zinc Acetate
Peridex (Control): 0.12% Chlorohexidine Gluconate,
Colgate Professional Breath Lozenges: Zinc Chloride
Water (Control)
Breath-a-Less: Xylitol
Rembrandt Dazzling Breath Drops: Sodium lauryl sulfate
Breath RX: Zinc Chloride
YOW: Sodium Bicarbonate

The patients arrived at the clinic in the morning hours having abstained from food, drink, brushing, & flossing for 8 hours.

The patient was asked to keep mouth closed for 2 min. to concentrate oral gases. Initial organoleptic measurements were taken to create a baseline odor level for comparison.

The patient was asked to use the assigned treatment.

After treatment use, organoleptic measurements were repeated every 3 min. until odor returned to baseline level.

The patient was asked to close their mouth for 2 min. to allow oral gases to concentrate. The air sampling tube was then inserted deep into their mouth and Jerome 631-X sampling was initiated. The patient then used the assigned treatment. The above steps were repeated to calculate H₂S percent reduction.

Results Section

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These data are based on the organoleptic scores. Products are color coded and listed in order from best to worst. The "Y" axis is the lists the product masking time in min. Three significance groups were found among the products tested. Notice the position of the water control. Tooth & Gum Tonic masked oral malodor numerically longer than all products tested, but was found in the same significance group with Oxygene with zinc having masking times of 51 and 41 minutes respectively. Notice the position change of Tooth & Gum Tonic as we go to the next graph.

These are based on the Jerome 631-X scores immediately after treatment use. The same color coding exists as the graph before. The "Y" axis is now % H₂S Reduction. Two significance groups were found with Tooth & Gum Tonic in the last group. Products containing chlorine dioxides and zinc active ingredients are found in the first group, having 86 - 97 % reduction. This means nearly all H₂S has been eliminated immediately after using treatments containing chlorine dioxides or zinc. The difference between these graphs is one is organoleptic testing and the other is Jerome H₂S testing. We do not have complete data yet on the long term effects products have on H₂S.

Note: By switching back and forth between these two graphs, these data indicate that there is something in addition to H₂S that is responsible for the oral malodor.

1. Organoleptic judges noted day to day variations in patient’s oral malodor. This was confirmed by the Jerome 631-X.

2. Products with strong mint flavoring were more effective for masking odor clinically.

3. Products with active ingredients like CLO₂ & Zinc tended to eliminate H₂S scores immediately after rinse.

Conclusions Section

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Detection: Organoleptic judges consistently detected odor. It was the most sensitive and reliable method tested. The Jerome 631-X detects H₂S consistently. It was the best method found for quantifying H₂S.

Elimination: Organoleptic measures matter the most clinically. Tooth & Gum Tonic with its strong mint/ herbal taste, was the most effective treatment tested masking odor for about an hour. Breath RX, Colgate Lozenges & Rinse, and Oxygene w/zinc significantly reduced H₂S levels the best among all treatments tested.

Bottom Line: Halitosis is perceived socially by the human nose. Therefore, we must find an instrument that measures what the human nose perceives and none has yet been found.

This research was sponsored and funded by Clinical Research Associates. Thank you.