But seriously you have inferred that parachutes are important from other high quality evidence… This is exactly what dentists are doing. Then they get criticised because the study was not double blind for the exact treatment they recommended.
Dentists are criticized because there are clinical trials about the effectiveness of dental cleanings and they do not support the hypothesis that dental cleanings have a beneficial effect on dental health.
https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD...
It does not compare cleaning with never cleaning. It is not evidence that you should never do a dental clean. It does not refute the idea that cleanings are beneficial.
I'm not here to tell you personally what you should or shouldn't do. By all means keep doing dental cleanings, continue seeing your chiropractor, routinely checkup with your naturopath or guru, or whoever else you want to pay money to for whatever reason you want.
I'm just pointing out the objective fact that there is no evidence that doing so will provides any observable health benefit. It might benefit you psychologically, it might encourage you to take better care of your teeth if you see your dentist regularly, who knows... but as far as the science goes, well there just is nothing to substantiate dental cleaning.
https://www.researchgate.net/publication/230768070_Is_the_Ev...
https://www.cadth.ca/sites/default/files/pdf/htis/oct-2013/R...
https://www.ncbi.nlm.nih.gov/books/NBK554695/
https://www.cochrane.org/news/routine-dental-care-does-evide...