Funny you ask for scientific research to support OP's argument, then you follow it up with a personal anecdote about milk fixing your teeth problem in a month (which it assuredly did not).
The reason your teeth still have enamel is that they are constantly being remineralized with minerals (including calcium) in your saliva being deposited on the top surface of the tooth.
If you consume less calcium, less calcium will be in your saliva, and that’ll slow that process down, while erosion continues normally (leading to sensitivity and eventually cavities)
if the problems he’s referring to are sensitivity (not related to gum disease), and he wasn’t getting enough calcium without milk, it’s quite possible that milk (calcium) reduced the sensitivity.
Link?
> Even worse, milk increases calcium loss in bones, resulting in higher rates of fractures.
I would love to read some serious research on this. Some 3-4 years ago I read similar advice, stopped drinking milk for about 5 months and started having serious problems with teeth which I never had before. Started drinking milk again and a month later all the problems disappeared.
People, don't stop drinking milk just because a random person on the Internet said so.