Dr. Koronczay László Ultrasonic White teeth whitening system – enhancing the effectiveness of teeth whitening by ultrasonic treatment Teeth whitening is the area of cosmetic dentistry that the public is most interested in, and as such it's one of the fastest developing field. Being a cosmetic treatment, it involves extra profits, however, the expectations are often unrealistic. As fast as possible, blindingly white teeth, without pain these are the basic requirements. There are many teeth whitening system in the world, but nearby all use the whitening effect of oxygen evolving at the decomposition of various peroxides. Look after what are peroxides ant what should be known about teeth whitening. The hydrogen peroxide is a clear, colorless and odorless liquid miscible with water unrestrictedly. Its chemical formulae is H-O-O-H as H2O2. As from the formulae could be seen two oxygen atoms are directly connected (-O-O-). This combination of two oxygen atoms is denominated as a peroxide group. The feature of this peroxide group that the oxygen atoms connect easily to other molecules or groups The formula shows it unambiguously that the two oxygen atoms are directly bond to each other (-O-O-). Such a combination of two oxygen atoms is called a peroxide group. A characteristic of this peroxide group is that the oxygen atoms easily bond to other molecules or groups through intermediary reactions. This reaction is called oxidation, and the oxygen given up is called the active oxygen. Out of the active oxygen compounds, hydrogen peroxide is the simplest. H2O2. has a wide variety of uses: it's a disinfectant, oxidizer, reducing agent and oxygen supply. When brought into contact with certain enzymes, pollutants, certain metals and their salts (Fenton reaction 2), alkaline compounds and UV radiation, hydrogen peroxide is activated and it rapidly decays. During this activation or accelerated decay, a large amount of disinfectant oxygen is released. At the end of the reaction the hydrogen peroxide perfectly decomposes into water and oxygen. This is the most interesting characteristic of hydrogen peroxide.1 The production and decomposition of hydrogen peroxide is also related to ultrasound. If we want the whitening material to act not only on the surface of the teeth, we have to know about the permeability of the enamel and the dentin against hydrogen peroxide. According to the literature, this value is extremely varying, much more than the concentration of peroxide can be varied in commercial whitening systems. (10-38%) (Probably this is the reason, why every whitening system can be successful - just not for everyone, according to my and my colleagues' experience) In-office whitening systems can be classified into 3 groups: 1. The material is applied to the teeth and then we simply wait 2. The material is activated by light (including laser and UV lamp variations) 3. Ultrasound is used for activation. The efficiency of the whitening depends on how much material reaches how deep into the tooth. Different solutions have been developed to increase the effect, but none of them have been perfect yet. The apply-and-wait method can have two drawbacks: Either the system uses a syringe, in which case the material should be slightly acidic in order to stabilize the peroxide, and the material decays slowly after the application as well. Systems with 2 or more components likely contain Fe+3 or alkaline constituents, which accelerates the decomposition of the peroxide, but we cannot control the direction in which the active oxygen is released from the gel applied to the surface. Photoactivated materials can release the oxygen rapidly, but have the same problem as the chemically activated materials: they cross the enamel with difficulty. The ultrasound drives out the peroxide from the gel rapidly, and decomposes it, and the vibration brings the material deeper into the tooth, but it is difficult to control the gel containing the peroxide in commercially available systems, and so until now only concentrations similar to that of domestic teeth whitening systems could be used. That's where it came up how the process could be made more efficient Photoactivation was rejected, because on one hand, working with light has a lot of drawbacks: only UV light decomposes directly the hydrogen peroxide (10), but UV light is dangerous and the mucous membrane, face, etc. have to be protected; in other systems the heat is the activator (which can be damaging to the pulpa), or some photoactivated peroxide activator is used; while on the other hand, activation can be done chemically in a very simple way. (11) Using ultrasound to accelerate chemical processes, such as bleaching with peroxide, is known in the art (567), so we studied the ultrasound system. How can ultrasound be used in a way that doesn't result in the gel spilling from the spoon , and so higher concentration is possible during the treatment. Ultrasound is conducted well by water and unclosed cell materials saturated with water, which led to the idea of using the micro brush, well known in the art, as an ultrasound transducer. This led to the development of a system that has numerous advantages compared to other commercially available systems. It improves the efficiency of any system that uses chemically activated agents, no large investment is needed, etc. The system is called Ultrasonic White, and is under patent protection. What is the “UltraSonic White®” whitening system? The Ultrasonic White whitening system is a apparatus based on the characteristic of ultrasound that it can accelerate chemical processes, and is under patent protection in Hungary. What does the “UltraSonic White®” system consist of? It consists of a handpiece which vibrates at a certain frequency, a head that conducts the vibration onto the teeth without damaging them, and a chemically active gel. EXPERIMENT: We conducted an experiment to prove the effectiveness of the apparatus. After talking to several companies distributing teeth whitening materials, Heller Hungary provided us with an appropriate amount of teeth whitening material, called Hellerdent Supreme White 40®. After several preliminary experiments, we developed an adequate photographic method and laid down the steps of the experiment We were looking for answers to the following questions: 1. The result of the ultrasonic whitening isn't just a placebo effect from the dehydration of the teeth. 2. We can improve the effect of a given commercially available material. (Hellerdent Supreme White 40®) Description of the experiment The aim of the experiment is to observe and evaluate the effectiveness of the ultrasonic whitening treatment. Steps of the experiment: 1. Adjusting the camera: - setting date imprinting on - manual settings: focus 5,6 shutter speed: 1/100 - white balance set on a test sheet - macro zoom is set on 2. taking a test photograph on a black and white test sheet 3. the patient signs a declaration of assent 4. taking an initial picture of the patient with a mouth straddle 5. teeth whitening: surface anaesthesia of the mucous membrane gingiva barrier lege artis apply the whitening material lege artis a 10 second ultrasonic stimulation per teeth on the right side with the Ultrasonic White¤ apparatus whitening for 3x 20 minutes washing the material completely off, remove the gingivabarrier 6. Taking a picture with the mouth straddle on. 7. The patient fills out the test form. 8. The patient is asked to return after at least 2 days. 9. Taking a picture according to the settings detailed above. 10. The other side is whitened following the directions of the manufacturer. 11. Taking a picture of the result. 12. Taking a picture after 2 days. The first picture was taken at the beginning of the experiment, the second immediately after the ultrasonic whitening treatment, the third 2 days later, the fourth after normal whitening, the last 4 days later. The experiment may seem a little complicated, but it was the only way the difference between the 2 sides could be evaluated, and also the whitening from the dehydration of the teeth, and the redarkening, which is often mentioned on internet forums as a drawback of the concurrent ultrasonic treatment. 12 persons took part in the experiment. There were 2 unusable results (imperfect photography, the patient didn't return), 7 partially usable results (didn't return, filling of crown on the front surface) and 3 valuable results. Evaluation: We evaluated the resulting pictures in the HSB colorspace (47), which is based on the human color perception, and which is the best for teeth whitening. A typical area of the front teeth were averaged, and the color could be expressed using 3 numbers. HSB colorspace is based on human color perception. It uses 3 basic properties of colors: Hue (H): the frequency of the light that the object emits or absorbs. Hue is expressed as an angle between 0 and 360 degrees, according to its position on the standard color circle. In general it is referred to by the name of a color, such as red, orange, green. Saturation (S): the strength or clarity of a color. Saturation is measured as a percent – from 0% (gray) to 100% (full saturation). Gray, white and black, that can appear on a grayscale image, have 0% value. A saturation value of 100% means the clearest variation of a color. Brightness (B): the brightness or darkness of a color which is also expressed as a percent between 0% (black) and 100% (white). At the end of the experiment, we asked the participants to fill out a form: 1. Did you notice a difference between the right and left sides during the treatment? If yes, what was it? 2. Please give an estimation, how much discomfort did you feel during the 3 cycles . (1 none at all, 5 terrible) First 20 minutes:... Second 20 minutes:... Third 20 minutes:... 3. What was the most uncomfortable during the whitening treatment? 4. Are you satisfied by the result? (1 no - 5 very much) 5. How much money would you spend on such a whitening procedure if the effect lasted for 5 years? Due to the small number of cases no statistical assessment was done, but the evaluating graphs are also revealing. The graphs show that both the peroxide and the dehydration had the effect of increasing the saturation of the teeth, with almost no effect on its brightness or color. These measurements can be used in practice as well to predict the colors expected after the whitening treatment already at the time of the restoration necessary before the treatment. (table x) Color saturation decreased by 5.92 points on average (from 24.69% to 18.77%), which corresponds to a 34% „whitening”. This corresponds to a A3-B2 color change on VITA color scale. Following the directions of Hellerdent Hungary, the whitening was 4.6% on average – 28.76% less than when using ultrasound. The „whitening” effect of dehydration was also studied, it changed from 22.17 to 17.67, but after a few days, it returned to 21.33. The fact that it didn't exactly return to its original value is explained either by the uncertainties of the measurement or by that the patient received instructions to wash their teeth, what to eat, etc. and the positive effects of these could be observed in the measurements. The graph above shows that after the whitening treatment of the right side, the left side also whitened due to dehydration, but by the time of the next treatment, this already returned to its original value. The „whitening” effect of dehydration was also studied, it changed from 22.17 to 17.67, but after a few days, it returned to 21.33. The fact that it didn't exactly return to its original value is explained either by the uncertainties of the measurement or by that the patient received instructions to wash their teeth, what to eat, etc. and the positive effects of these could be observed in the measurements. Case 1 22.5 20 saturation 17.5 15 12.5 10 jobb oldal bal oldal 7.5 5 2.5 0 Alapáll Jobb Kontro apot old UH ll Bal sima feh. Eredm ény event The graph above shows that after the whitening treatment of the right side, the left side also whitened due to dehydration, but by the time of the next treatment, this already returned to its original value. Chance so ordained it that one of our patients had a ceramic fused on metal crown on teeth #11. We did not exclude him from the experiment (it was very hard to find patients) – according to the literature peroxide has no effect on ceramic, so it could be used as a reference. However, after evaluating the pictures, it turned out that some sort of „dehydration” effect is indeed in place, color saturation was definitely level lower by a point on pictures taken after the whitening procedure. Of course at the end the crown didn't become whiter, it had the same value as initially. Eset 2 25 22.5 színtelítettség 20 17.5 15 12.5 jobb oldal bal oldal 10 7.5 5 2.5 0 Alapáll Jobb Kontro apot old UH ll Bal sima feh. Eredm ény esemény The evaluation of the forms was also revealing. For patients explained that the ultrasonic treatments were more sensitive (which was expected), but they found the aspirator and the mouth straddle more discomfortable than the pain. It is surprising that 4 patients found the mouth straddle the most discomfortable, 3 the aspirator and only 2 said that it was the pain. In these cases it turned out that the gingivabarrier was leaking and the peroxide was burning the gum. (It's unpleasant, but disappears within a few hours spontaneously.) The average satisfaction was 3.71, most participants gave 4 on a scale of 5. Those who had previous experience with teeth whitening gave better grades. At the evaluation of pain it turned out clearly that discomfort doesn't increase linearly by time, but this could have multiple reasons. It is possible that the pain really increases, but it is also possible that the same physical stimulation is felt more acutely after some time. Sensitivity 25 22.5 relative pain 20 Eset 9 Eset 8 Eset 7 Eset 6 Eset 5 Eset 4 Eset 3 Eset 2 Eset 1 17.5 15 12.5 10 7.5 5 2.5 0 20. perc 40 perc 60 perc minutes It is also edifying to see how much the patients would spend on such a treatment. Those who were aware of the prices of whitening procedures in Budapest almost uniformly said 50,000 Ft. These participants were typically women between 25 and 35. Men were less interested in cosmetic questions, they would typically spend an amount between 0-10,000 Ft on teeth whitening. Young adults gave an amount in between. How much would you spend on whitening 0-10000 Ft 10001-20000 Ft 20001-30000 Ft 30001 Ft < In summary , the effect of teeth whitening agents, such as the Supreme40® sold by Hellerdent Hungary, can be improved by ultrasound. Whitening is not just a result of dehydration, a real and lasting change is observed. The experiment raises some problems worthy of further reflections. After the ultrasonic treatments, the teeth kept whitening until next morning. This is logical, the peroxide penetrated the teeth and slowly oxidized the coloring compounds therein. If we aid the decomposition of peroxide e.g. by creating alkaline pH value, does this effect become more rapid, and can we reach the maximal whiteness already at the and of the treatment? Materials with alkaline pH decrease the sensitivity of teeth. (zz) Can this effect be utilized during the whitening treatment? References http://www.huwa-san.hu/hidrogen.php Introduction into the feature of hydrogen-peroxide (Bevezetés a hidrogén-peroxid tulajdonságaiba) http://www.hazipatika.com/topics/fogapolas/articles/Feherebb_a_fehernel?aid=20071017122648 http://www.trojanuv.com/en/business/ECTadditionalinfo.aspx http://garfield.chem.elte.hu/Zador/zador_PhD.pdf : J. 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