A recent study indicates that children living in the Himalayan mountain region in Nepal have lower levels of tooth decay than children living in suburban areas in the United States, despite the fact that people in the Himalayan mountain region in Nepal receive little to no professional dental care, while people in suburban areas in the United States see a dentist an average of 1.25 times per year. Thus, regular dental care is not helpful in preventing tooth decay.

The author claims that the people living in Nepal have lower tooth decay then the United States. To support this claim also mentioned about dental care received by people in both countries. Stated in this way the argument manipulates facts and conveys a distorted view of the situation. So therefore, the argument is weak and unconvincing.
First, the argument assumes that the children living in the Himalayan region have lower levels of tooth decay then the children living in suburban areas in the United States. Perhaps, the children living in the mountains range have similar level tooth decay as in Nepal. As the argument does not mention about the both countries average tooth decay of people, therefore it would be totally wrong to make a generalization about the situation.

Second, the argument also claims that Nepal people are not receiving any kinds of medical assistance from the government, in the united States people are receiving better dental care. It might have been a survey or report, who are presenting these kinds of statistics, may be Nepal's people go to neighbor country for dental care or may be they are using ancient method to lower tooth decay. If the argument had mentioned more details about their traveling to neighbor countries for checkup or any kind ancient method used, then the argument would have been a bit more clearer.

Finally, there are, however, a lot of question need to be answered, like, is their any kind of genetic difference that is cause of lower tooth decay?, or are people in both countries eating same type of food?. Without giving answers to these questions the argument is more wishful thinking rather than a substantive evidence.

In conclusion, the argument is weak and unconvincing due to the mentioned flaws. It could be strengthened by providing more relevant details about ambiance or food eating habits, because all these are important in considering tooth decay rate in any country. For accessing the merits of any situation firstly we need access most basic facts that are critical, without them accessing the merits are impossible.