Plasma Jets Could Replace Dental Drills 131
Hugh Pickens writes "The first electric dental drill was patented in 1875; modern drills grind the diseased portions of teeth away at up to 500,000 rpm. But dentists have been seeking less invasive ways of wiping out stubborn, tooth-decaying bacteria. Now Live Science reports that bacteria-killing jets of plasma could soon replace the drills used to treat cavities in our teeth. Researchers recently demonstrated that a small, blowtorch-like device emitting a relatively cool beam of purple plasma could eliminate oral bacteria in cavities, leaving more tooth structure intact than a drill does. To test how well 'cold' plasma jets (about 100F or 38C) sterilize tooth material, researchers took slices of dentin from extracted human molars, doused them with bacteria, and torched them with the plasma jet. An inspection via a scanning electron microscope of the damage done to the germs shows bacterial remnants had holes in their cell walls. When the plasma jet fires, it charges oxygen in the surrounding air, creating highly reactive molecules that can break down the bacteria's defenses. Researchers believe the technique could be available to general dentistry in three to five years."
Home use? (Score:5, Interesting)
Would this kind of device be useful in the bathroom? Probably not as a replacement for flossing or brushing, but fighting plaque build-ups in places you can't really get?
Hard coating? (Score:5, Interesting)
I've always wondered why they haven't developed a hard coating for teeth that would prevent most cavities and why we don't have vaccination against caries and periodontal pathogens.
It often seems like the basics of dentistry have changed little. There are newer materials for crowns and tooth-colored fillings, CNC machines and 3d modeling for crowns, but AFAIK going to the dentist is little different for me now than it was 40 years ago.
I sometimes wonder if advances in preventive dentistry aren't limited by the structure and practice of dentistry itself. Plus, dentists being dentists, they have a built-in interest in high-quality preventive care (high-frequency flossing, rinses, brushing, etc) and thus themselves develop few of the chronic problems that plague the general public and thus don't devote resources to better passive preventive systems/technologies as they believe the ones available are "good enough".
In a way it kind of reminds me of the problems non-technology people have with computers that technology people don't suffer from; these issues don't really get addressed within technology itself very aggressively because to the people who don't have these issues, they aren't considered serious problems or are considered side effects of other problems (general ignorance or lack of intelligence, etc).
Re:Hard coating? (Score:4, Interesting)
Not the only use (Score:5, Interesting)
This isn't the only use. I watched an interview with the guy who invented the cool plasma. It can be used to sterilize hands as well. You know the sterilization chamber from Star Trek, the one you enter with your clothes off after coming back from a planet and get eradiated. Well you can do that too with cool plasma.
Re:right... (Score:5, Interesting)
The drills really aren't that bad, assuming that the dentist doesn't botch it. No new technology can be expected to solve poor technique or accidents.
Actually, the way I understood this is that plasma is used to disinfect the dentin, instead of mechanically drilling away the infected part. So there is less potential for mechanical damage as well. Some drilling is probably necessary to remove the mechanically decayed part, but there is less need to remove extra layers just in case.
Re:Hard coating? (Score:5, Interesting)
why we don't have vaccination against caries
Last I heard, one is currently in human trials. It works by replacing the bacteria responsible with a different strain that doesn't create lactic acid, and therefore doesn't cause caries.
In tests on rats, it provided a permanent solution. Here's hoping it works out for us too.
Re:Hard coating? (Score:4, Interesting)
Last time I talked to a Dentist on a related subject, he told me that that's by design - better that your natural teeth wear on the sealant/crown/whatever than that the sealant/crown/whatever be hard enough to cause wear on your remaining natural enamel.
Re:right... (Score:5, Interesting)
Different clinicians practice to different standards and use differing treatment standards and different diagnostic methods. A dentist using the older standard probe and X-ray technique will miss more, using new digital radiography and new diagnostic aids more will be found. Many small caries can remain sub-clinical for decades or even unmineralized and get smaller or they can grow explosively. Sometimes the "caries" are caused by physical traumas like abfraction [wikipedia.org] due to bruxism [wikipedia.org], clenching and other parafunctional habits. Unfortunately there can be differences based on economic considerations as well.