You are still the same rank, but the name depends on the branch. For pay, add base O-3 (just google military pay chart) and look up accordingly. Base pay (taxable) will increase after 2, 3 and 4 years. BAH(non taxable) is completely dependent on location (San Diego, CA would be more than Norfolk, VA), as well as if you have dependents or are single. BAS(non taxable) is set at around 250ish a month. IP pay for being a general dentists is 20k a year.
So,
Base (look at military pay chart 2021) + BAH(look up bah calculator and put zip code of base) + BAS (currently $266.18/month) + IP pay
Should give you a rough estimate.