Many degrees are worth getting. Some degrees are not worth the cost.
In general, a dental degree will get you ~120k right out of school (bottom 10% salary figure). That is significantly above the median income in the country.
If you compare to an electrician, sure, the electrician may spend 200K less on school, and they may start working 6 years sooner, and they make a decent salary as well.
per salary.com
Median range for 0-2yr experience electrician is 37-50k ~43K is median figure.
Median range for 3-5yr experience electrician is 45-58K ~52K is median figure
After 5 years, median salary is around 60K.
So, in the first 2 years the electrician will make about 86K. In the next 3 years, another 156K. In the next year, 60K (very rough figures, location obviously plays a big role here.)
So, 6 years, dentist in school pay 200K. Electritian working make 300K
so figure 300K + 200K, electritian has about a haly a million dollar "head start" vs a dentist.
But, in the long run, a Dentist starting out over 100K, (Range to cover 80% of dentists is 120K to 210K, with median of 150K) or more per year will "break even" with the electrician in about 15 years.
Over the course of a career, assuming retirmeent age of 65, and electritian works from 19-65, dentist works from 25-65
Dentist would earn around 6 million during the career in "current" dollars over a 40 year career earning an avg of about 150K per year...
Electritian would earn about 2.76 million over a 46 year career averaging about 60K per year overall. (more if they start their own business, or if they specialize in aircraft or some specific industry vs general construction.)
So, it takes a LONG time for most college degrees to pay off vs trade schools, however, certain degrees provide HUGE earning potential increases, thus, are in most cases worthwhile.