Hi,
well for those who don't know, the 4 Marian dogmas are:
- Mary is the Mother of God
- Perpetual virginity
- Immaculate Conception
- Assumption
1, 2, and 4 are also believed by the Orthodox. They disagree with the immaculate conception cause they don't believe in original sin, but they
agree that Mary did not commit any sins during her whole life. So really the Orthodox view on Mary is much closer than the Protestant view.
As for dogma and salvation.
Here is a list of Catholic dogmas:
http://www.theworkofgod.org/dogmas.htm
It's not as simple as - believe these things and go to heaven, don't believe them, go to hell. Of course if this were true, then only Catholics would have a chance of salvation, and the Church teaches that others could be saved too. If someone is lead by God to believe in any of these dogmas but rejects them, this could be a sin. If they don't understand them, or just don't believe them, it's more complex. The simple answer is that if they follow Jesus they can be saved.
What dogma is: something that the Church has stated is the truth, and the faithful (Catholics) are obligated to believe it. If they don't believe it, they're going against Church teaching. The concept of dogma clarifies the role of the Church as the interpreter of Scripture and the foundation of correct theological understanding. As it says in the Bible, the Church is the pillar and foundation of truth.
God bless