Idle Thoughts: Sonics

My dad mentioned to me recently that the head of the UW bioengineering department had some significant part in the development of the sonicare toothbrush. It seemed odd to me because a rotating bristlehead seems like a clear industry side no research pure engineering making an object to fit this market need kind of item. He claimed that the device may actually do something involving sonics of some sort.

I was thinking about this while using my sonicare toothbrush this... Sunrise during period of insomnia (It's a shame too. I slept fine since the end of finals and then BAM, this gets me.) Anyway, I was thinking about using sonics to attack plaque.

So what is plaque? I don't know for sure and I didn't look it up because what I'm writing now is a transcription of thoughts I had while shaving and brushing my teeth, but my understanding is that it's micro-organisms that live in and around your teeth. They feed on the food residue and then later on the tooth itself. The secondary phase of the feeding makes them a pathogen, of sorts, and hence toothbrushing.

So how would you use sonics to attack microorganisms. One thought occurs to me. Constructive interference. If you knew a lot about those micro-organisms you could make a clear guess at the wave pattern of a given sound going through their body. You could then find the wave that would cause an amplification of itself inside the body, resulting in a sort of sonic tremor inside the cell, ripping the cell open.

That's a theory. I'm not sure it's valid. Unlike normal wave mediums cells have an extremely complex structure, so it may be impossible altogether, but lets assume for now that it is possible given enough data about a kind of cell to find the frequency which will destroy it.

So how much do we know about cancer cells? In theory it shouldn't damage the surrounding tissue to much, you may have problems calibrating it so that the wave arrives properly after going through the person, but I'm sure you could get around that with either extensive testing on a patient by patient basis, or tiny micro-emitters placed inside the patient.

A key fault in my thinking occurred to me though. Cells aren't all that different from each other. It may be that the frequency which would kill off a brain tumor would also kill off all of the neighboring non-tumor brain cells. It depends heavily on how much a cell changes when it becomes cancerous.

There's a lot I don't know here but it's an interesting idea. It's another one of the "force at a distance" things that fascinates me.