Which is more effective for treating acne, oral medication or topical medication?

I am planning to visit a dermatologist to begin full-scale acne treatment. I have heard that the prescribed medications include oral drugs (such as isotretinoin) and topical ointments. I am curious about the pros, cons, and side effects of each drug. I would also like to know the criteria for determining when oral medication is generally preferred and when topical medication is better. I would appreciate honest reviews from those who have personally received a prescription and used these products.