Looking for UV LEDs ...tia SAL

There aren't any LEDs in production yet producing germicidal UV. Also, expect any earlier model such LEDs to not irradiate the whole inside of your mouth to kill bacteria all over within an hour - germicidal lamps that resemble fluorescent lamps are better for this and will be even when such LEDs do become available.

More considerations:

1. Sufficient germicidal UV to kill bacteria kills the top layer to few layers of cells of all exposed tissue in your mouth that has live cells exposed to the UV.

1. Human cells damaged but not killed by UV may have genetic damage that could cause cancer.

2. Bacteria in locations shaded from the UV survive and could replenish the plaque in your mouth in less than a day. Bacteria under the gumline are shaded from germicidal UV.

I recommend brushing and flossing, brushing with fluoride-containing toothpaste, drinking fluoridated water, and getting the tooth surface treatments that dentists normally provide.

With usual good cavity prevention tactics, the main hazard of plaque is periodontal disease - also mitigated by brushing and flossing.

- Don Klipstein ( snipped-for-privacy@misty.com)

UV LED currently in production are mostly in UV-A range (longer wavelength) and won't do enough to do anything but light up fluorescent materials. What you want is UV-C and no LED exists that can produce UV-C range.

Beside unless you can design a shroud that keeps the UV-C only in the target tooth and not the whole mouth, you'd do more harm than good to kill germs. Heck you'd need a welder's mask just to see where the UV bulb is going as exposed eyes would suffer permanet damage leading to eventual blindness.

Current germicidial class bulbs are too big to fit in the mouth. Stick with drills and disinfectants for now.

You're out of luck, bub... Sorry...

Yeah... At mongo-huge wattages, in specially designed (*NO* shadows or hidden nooks and crannies - Does your mouth fit that description?) containers, where it sits for an amount of time you'd consider absolutely ridiculous if you had to do it on a daily(or even every other day) basis. Also, water, glass, and metal are immune to the genetic damage (AKA "cancer-causing") effects of UV exposure. I *VERY* highly doubt you can say that for the inside of your mouth... I imagine it'd probably be less than a year before you sprouted your first precancerous lesion, assuming your whole damn HEAD didn't simply explode into one giant tumor.

Then there's the fact that there is no such LED currently being made, and there isn't likely to be one for quite some time.

In other words, forget it. Your idea has more holes in it than a screen door. Brush, floss, and see Dr. Drill-n-fill as needed, and leave the UV anti-bacterial treatments to the water plants, where they actually have a chance at working.

This UV wavelength will also create cancer.

I don't know of any UV LEDs' that work in the 254 nm region for sterilization.

As for exposing the inside of your mouth to UV radiation that can kill bacteria, this can pose a danger for cell damage to the gums, and to the other tissues in the mouth. This can pose condition where by cancer cells can be easily formed. The exposer would have to be for a determined period of time, depending on the strength of the UV radiation, and the distance from the emission source.

Nothing will beat good dental habits, such as proper flossing, and brushing of the teeth to keep up with proper hygiene.

As for killing bacteria in the mouth, there are some very effective mouth washes. They in themselves have other side effects that can be hard on the mouth tissues and gums. They also kill friendly bacteria that is good to have for the system's self defence.

If the plaque on the teeth is not properly removed, even though the bacteria of its makeup is destroyed, it will eventually harden, and thus cause a greater frequency of dental cleanings to be done. This plaque puts a coating on the teeth that can be acid in nature, and thus cause the teeth to be eaten away. The plaque can sometimes form below the gum line, and thus cause gum problems, which can lead to more serious problems. Cavities below the gum line are serious, and will usually require gum surgery, to be able to fix the tooth.

With proper dental care, the chance of having cavities is much less, than without. See your dentist regularly for proper cleanings, and examinations. This way, you should be able to avoid problems.

Brush your teeth often, and brush and floss every day before going to sleep. After your teeth are cleaned, never eat, or drink anything with substance, other than water. Never get up in the middle of the night to have a snack, and not re-clean your teeth. Eating within 2 hours of sleeping is unhealthy, and will promote a greater degree of cholesterol accumulation in the arteries. Snacking late in the evening, or during the night is very unhealthy. When we are sleeping, our liver tends to makes more cholesterol.

When you get up in the morning, it is important to brush your teeth. The morning accumulation of bacteria in the mouth, plays a great part in making plaque accumulation on the teeth. The front lower teeth are most effected.

Brush your teeth right after you finish breakfast. This is actually best for after each meal.

I'm not aware of LED's available in that wavelength, the shortest wavelength I know about are in the 370-390 nm range.

But, I'm not sure this would be a good approach to what you want to do. This wavelength is particularly damaging to skin. Also, what about the bacteria located under the gums, where a uv source would not reach?

Mark

Look up the SUVOS program funded by DARPA. Its aim was to develop UV LEDs for various biological sensing applications. As I recall 350 nm and 280 nm were their target wavelengths because each wavelength is good for exciting a certain class of biological molecules. I don't think that a wavelength as short as 254 nm was thought possible, but they made a lot of progress.

Bret Cannon

I'm not sure I'd like 254nm bouncing around inside my mouth.

Jon

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The UV needs to be short wavelengths in order to sterilize and have enough energy to dissociate oxygen molecules into ozone. You may not be able to get those short wavelengths from a LED. But it should be easy to do it with mercury arc.

I remember when I was a kid, they had UV lamps inside the dryer. When it was done drying a load of clothes, I could smell ozone when they were taken out. The bulb was similar to a regular incandescent light bulb, but it had a dark coating, and there was mercury and mercury vapor inside. Somehow, after the filament heated up for awhile, the arc would go across the mercury vapor. It might have been a bimetallic strip that opened the filament after a time, so that there was no incandescence, only the mercury arc.

Note, I said that there was the smell of ozone. Putting UV rays into your mouth might create ozone, and you might have adverse health effects from it. I know that it's not good to breathe ozone in high concentrations, even tho it's all around us in the air pollution.

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I love your not so prosaic wit, Don, especially the 'screen door' bit. Someone mentioned that germicidal bulbs are too big to fit in your mouth, but it would be easy to make a small set of electrodes that could produce an arc with a lot of short wave UV in it. Of course there might be the problem of heat, and the ill effects you mention above. So it's probably a Really Bad Idea(TM).

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Gawd! This person sounds like a mother, a dentist, a Dr., and a toothpaste commercial all wrapped up into one! Next thing you know, s/h/it will be telling us that it's bad to breathe the pollution, so stop breathing! :-/

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Here's an exerpt from one of the docs I dug up with a SUVOS search. Some inetesting info about LEDs saving electricity, fuel, etc.

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Google is not affiliated with the authors of this page nor responsible for its content. The U.S. Department of Energy released two studies that analyzed and estimated energy savings of solid-state lighting (mainly LEDs). One study estimated the energy savings potential if solid-state lighting can achieve certain price and performance criteria. The report considered two scenarios?one where the technology receives a moderate national investment of $50 million per year and an accelerated scenario based on an investment of $100 million per year. Under the moderate investment scenario, in 2025, the energy savings associated with solid-state lighting could total approximately

The second study that looked at LED use in niche applications concluded that LED traffic signals use only 10% of the electricity consumed by the incandescent lamps they replace, and they last much longer, allowing for additional savings through reduced maintenance costs. Exit signs were identified as another important niche application, where an estimated 80% of U.S. exit signs now use LEDs. LEDs also have made inroads into mobile applications, such as brake and signal lights on automobiles, buses, and trucks. To date, 41 million gallons per year of gasoline and 142 million gallons per year of diesel fuel have been saved because of LED use on these vehicles. (Fuel savings were calculated based on the lower accessory load on the engine.) If all automobiles, buses, and trucks were to convert to LED lighting, 1.4 billion gallons per year of gasoline and 1.1 billion gallons per year of diesel fuel could be saved (Navigant Consulting Inc., 2003a§).

Anything designed for disinfection will cause as much damage to the inside of your mouth as to the germs you're trying to kill. That's the difference between DISINFECTANTS (used on non-living objects) and ANTIBIOTICS (used on living things). Ask your dentist to prescribe PERIDEX.

Not to mention the moisture in the victim's... er the paitent's mouth could cause the electric discharge to jump around and fry the mouth.

I remember those "dryer bulbs".

They have a filament and require a ballast to limit current. A 40 watt

These lamps produced both the 253.7 nm main germicidal wavelength of mercury and the ozone-forming wavelength of 184.9 nm (which is also germicidal). Some other germicidal low pressure mercury lamps have output of 184.9 nm minimized to minimize ozone production.

As for how bad to breathe is the ozone from a lamp that generates ozone? If you can smell it, the concentration is higher than that in summertime urban smog.

- Don Klipstein ( snipped-for-privacy@misty.com)