U.S. health insurance focuses on the healthcare of subscribers, and dental treatment has been recognized as a separate field in terms of health insurance.

General health insurance provides coverage centered around health-related treatments such as emergency room visits, hospital admissions, surgeries, and chronic disease management, while dental treatment requires specialized services such as preventive oral care and dental treatment.

In the case of dental treatment, prevention and management are essential, but the variability in treatment methods and costs, as well as the significant differences in cost burden depending on each individual's oral health status, make it difficult to settle insurance claims in the same way. In the early days of U.S. health insurance, the costs of dental treatment were quite high, and due to insufficient coverage, many people struggled to maintain their oral health.

From the 1960s to the 1970s, dental insurance products emerged, allowing many Americans to receive regular dental check-ups and treatments without financial burden. Early dental insurance had relatively low coverage limits and was a limited form that included only some treatment items, but over time, insurance companies began to offer various products and benefits to remain competitive. Along with this, as awareness of dental health improved, preventive dental treatment was emphasized, and consequently, the necessity of dental insurance became prominent.

Additionally, due to the characteristics of the private insurance system in the U.S., regulations and coverage vary by state, leading to a variety of insurance products. Some employers offer dental insurance as a package with health insurance, but most maintain a structure where individuals must enroll in separate dental insurance.

From the insurance company's perspective, if dental treatment costs are included in health insurance, it could lead to an increase in overall premiums and greater risk burden, so it has been determined that operating as an independent product is more efficient. Currently, U.S. dental insurance has developed into products that offer various benefits from basic preventive treatments to prosthetics and orthodontics, allowing subscribers to choose customized coverage according to their oral health status and financial situation.

Historically, the dental field has developed independently, requiring separate specialized education and qualification processes from medicine, and dental treatment has characteristics that emphasize regular check-ups, preventive care, and routine management.

These differences are also reflected in the design of insurance products, as dental insurance often provides low coverage limits and limited benefits. From the insurance company's perspective, predicting dental treatment costs is difficult, so to avoid additional financial burdens, it is deemed more efficient to separate health insurance and dental insurance.

Moreover, the competitive nature of the private insurance system in the U.S. and the diverse regulations in each state provide the advantage of allowing subscribers to choose customized coverage when dental insurance is operated as a separate product. If dental treatment costs were included in health insurance, it would likely lead to an increase in overall premiums and greater cost burdens for insurance companies, which would ultimately be passed on to consumers.

Due to these structural factors, dental insurance has established itself as an independent insurance product in the U.S., playing an important role in ensuring premium stability and the financial soundness of insurance companies. I hope this helps you understand why dental is an option when choosing health insurance in the U.S. I believe you can also grasp the reason why vision is an option for the same reason.