Reason wWhy getting braces isn’t a common thing in Japan

It costs around 700K-1.2M yen, and it isn’t covered by the health insurance unless you need to dohave jaw surgery.

OR: surgery on your jaw

In most cases, when wbefore start theming, we have to sign basic paperwork saytating that orthodontists aren’t liable for side effectdamages that occur, so it’s very difficult to sue them even if itif something goes wrong*.

basic paperwork = consent
*if something goes wrong with the dental work

Today I’m going to talk about why getting braces isn’t common in Japan.

You don't need to keep this line, if you are reciting a speech then you can keep it.

Reason wWhy getting braces isn’t a common thing in Japan

More title-like. Since "why" already has the meaning of "reason", it's a bit redundant.

According to the 2020 survey by Japanese Association of Orthodontists, only ten percent of the people havesurveyed had braces.

Technically, the end of the sentence should be "only ten percent of respondents claimed having braces." With the phrasing in my suggestion, again, "have braces" is more technically accurate.

However, I think most people would write it as I've suggested. The "surveyed" is required because otherwise it's ambiguous what set of people you're referring to.

It costs around 700K-1.2M yen, and it isn’t covered by the health insurance unless you need to do jaw surgery.

"you need surgery" or "you need to have surgery done"
The wording "to do jaw surgery" would imply the patients are performing the surgery on themselves.

In my flashcards, I have this sentence, "父は胸の手術をした", and coming from English it's rather confusing because it sounds like 父 is performing the surgery, but Google says it translates to "my father had chest surgery."

In most cases, when we start them, we have to sign basic paperwork saying that orthodontists aren’t liable for side effects that occurdamages, so it’s very difficult to sue them even if it goes wrong.

"damages" here is kind of a legal term here meaning essentially "any injury, adverse effect, illness, etc., that comes from a service."

According to thea 2020 survey by the Japanese Association of Orthodontists, only ten percent of the people (in Japan) have had braces.

It costs around 700K-–1.2M yen, and it isn’t covered by (the) health insurance unless you need to do jaw surgery.

In most cases, when we start them, we have to sign basic paperwork saying that the orthodontists aren’t liable for any side effects that occur, so it’s very difficult to sue them even if it goes wrong.