Do people have more dental problems?

There are medical colleges which offer MBBS courses. In MBBS, information regarding all parts of the body are studied. Similarly, there are dental colleges, which offer BDS courses at bachelors level. In my opinion in BDS, information regarding only teeth are studied. Why there is a separate course for teeth at bachelors level? Do people have more dental problems? Is dentistry a complicated subject, which can't be clubbed with the studies of other parts of the body? Experts, please clear my doubt.