With all due respect, you don't know what you don't know. In case you missed it, I am a US dentist. I spend every working day dispelling laypeople's misconceptions about dental work. What work they have, what work they need, benefits and drawbacks, etc. Your post hits on some of the many very common misconceptions.

Fortunately, there are plenty of ways to check the efficacy of medical procedures.

You can get x-rays, MRIs and all sorts of after-care examinations performed by your choice of trusted doctors and dentists if you are unsure of the quality of care you received.

Not all work can be evaluated, even with x-rays, as restorative materials often hide the most important details. MRI is irrelevant for dental. X-rays are just a tool, not the final word, and they can't reveal certain things. Bacterial ingress and leakage is, for all intents and purposes, invisible. Most docs (in both medicine and dental) are exceptionally reluctant to disparage another's work. It is considered unprofessional and unethical to bad-mouth another professional. That's just how we're trained.

A strong indicator will be how you feel after the procedure, which is why I include patient surveys in all of my posts about medical care abroad. Very importantly, other than the higher-rated equipment, expertise and report accuracy, patient satisfaction regarding care quality in Thailand is rated higher than in the US, for example.

This could not be further from the truth. Discomfort and success are completely different things. Some extremely high quality, ultimately-successful treatments will make you feel like shit afterwards. Often, post op symptoms are more closely a matter of chance than they are of quality. Patient satisfaction and surveys are complete worthless bullshit, as evidenced by hospitals' Press Ganey scores, etc. See Goodhart's law. Docs hate chasing patient satisfaction because it is so poorly correlated with actual quality care. Telling the patient "no, this will have a poor outcome" gets you bad reviews, while doing a slipshod job that is unlikely to last but looks superficially good gets you patient satisfaction. I see it CONSTANTLY. Smooth-talking, kind-seeming, gentle dentists whose skills and ethics are complete trash. Patients can't tell the difference. This is why so many people love Nurse Practitioners, who are poorly trained and often happy to act as a rubber stamp for what the patient is asking for, even if it is not in their best interests. People love "yes men".

Remember, Yelp and Google reviews are both astroturfed by business owners, and used as a weapon by disgruntled people and competitors alike. There's a local dentist office that's still under construction and it already has 30+ 5-star reviews in Google. Hasn't seen a single patient yet. I would not be too trusting of reviews in general.

You have taken your subjective experience and tried to use that to say the work is objectively good. That's not how any of this works.

Now could that work actually be good? It could be. This is not to say that all foreign dentistry is bad, but SO MUCH OF IT IS. I know because I see it. The fact of the matter is, patients generally don't know the difference between good and bad work. I see patients all the time who said some absolute basement-tier-garbage work was done by their previous dentist, who they adored.

Incorrect. This applies to most medical care destinations outside of the US; follow-up care is essential abroad and is usually presented in a contract and verbally confirmed with you before any diagnosis even takes place, let alone a procedure. You have access to all the documents and files your hospital abroad does and are also free to share those or ask your hospital to share the documents with other doctors and clinics of your choice.

Ask any orthopedic surgeon what they think of foreign procedure mills offloading post-op knee-replacement care to an unfamiliar doc in the country the patient is visiting from. This is a huge issue docs discuss in private - patients flying to wherever for cheap, substandard treatment and leaving them to manage the complications. It's a big issue in places like FL and NY, but also broadly everywhere.

Many treatments, you get essentially one chance to get it right, and fixing it is either impossible or 10x as much difficulty. Getting it right the first time is priceless. You can fuck up a tooth in an instant. Destroyed. Cannot be fixed. Some errors are invisible and don't hurt right away. Many infections are painless or hard to diagnose from typical x-rays. Many compromised teeth spend a few years feeling normal before they fall apart. I know this because I see it every day. I'm the one who gets to fix others' mistakes - if they can even be fixed.

As a practicing professional who spent the majority of my training seeing a high % of international dentistry, it's hard to watch.