What Frequencies Are Emitted from Dental Drilling?

[K.A.]

I'm trying to figure out more about the occlusion effect and especially how to prepare best for dental visits...

Many have suggested drilling at lower speeds to reduce the noise (+ breaks and electric drills).

Probably this RPM reduction will reduce dB generation at the source. However, the charts I have found for the occlusion effect suggest a higher effect (dB increase) at lower frequencies (less than about 3 kHz).

If using a 30cc muff, a decrease in noise frequency from 1000 Hz to 500 Hz would actually increase the occlusion effect by about 10 dB, but is the noise generated reduced by more or less?

Peltor X5A has about 100cc of air in each cup, so I guess it would be touch zero occlusion effect at about 1 kHz and above (speculation from my side).

What is also interesting is that plugs inserted 23mm might have a negative occlusion effect at 3 kHz and above, though I have not fully understood how they might be able to actually reduce the bone conducted noise by being in the ear canal.

Well, my question is: what frequencies are emitted from dental drilling that occur at high and low speeds?

 

[K.A.]

After more searching I actually found some interesting papers, especially this:

Measurement of bone conduction characteristics for transmitted vibration sounds of tooth drilling

Just wanted to share.

This is however from 2007, and still no "active noise filter" for bone conducted noise on the market, as far as I know...

 

[russiancarl]

Sorry I don't know much about the occlusion effect, but I've had a lot of cavities filled and notice you mentioning upcoming dental work. I'd highly recommend finding a dentist that will go slow and work with you. The 3-5 seconds on, then 10 seconds off really helped me.

I also wore big earmuffs, though they didn't help much as the majority of the sound was from bone conduction. I also took NAC beforehand. I never had a spike.

 

[K.A.]

@russiancarl, thanks for your information.

The bone conduction of sound and the occlusion effect is kind of a difficult area as using certain types of ear protectors (e.g. plugs not very deeply inserted) might cause an increase in dB from the bone conducted noise at certain frequencies (due to what is called occlusion). So the occlusion effect in this sense is an increase in the noise level, which of course we do not want.

The increase in noise can be as much as almost 50 dB (!) at the lowest frequencies if using a plug inserted only at the entrance of the ear (the graph in my first post in this thread). The graph also shows there is potential increases up to 1000-2000 Hz. This is the reason when sometimes you use hearing protection, your own breath and the low frequency noise from merely walking or chewing sounds louder, they actually are made louder by the occlusion effect.