A dentist or hygienist without a phase microscope is like a blind dentist or a blind hygienist.
Maybe the question should be, Why a PHASE microscope? By putting a small amount of dental plaque from around your teeth under a phase microscope the hygienist or dentist and you can observe clearly on a video screen the activity level of these live bacteria. The bacteria that cause decay and periodontal/gum disease (we call them PATHOGENS) are mobile, meaning they move around a lot. Healthy bacteria, one’s that are neutral or beneficial under the phase microscope look like they are standing still, not moving.
If you are using what you think is an effective preventive home care procedure, regimen, or product, how do we know if it is working?
The ONLY WAY that we can see if what you are using or doing works is to see if you have reduced or eliminated the PATHOGENS, the mobile bacteria, the bacteria that cause dental disease.
You can only know this if you look at a sample of bacteria from your teeth under the gums (bacterial plaque) and see if the bacteria are still/not moving or are mobile/moving.
If there is no or little mobility you know your preventive procedure is working and is effective.
If there is still mobility compared to before you started, no matter what product, regimen, or procedure you are using, you KNOW now that what you are doing is NOT working.
Without a microscope you have no idea what is going on and/or wheter what you are doing has any value. How much dental disease you get in the future becomes luck.
So this is the reason that a dentist needs a phase microscope.