[Closed] Dead textures vertices!??

Hello.
I made a script that uses Unwrap modifier and some meshop methods.
The problem is that when there are dead vertices things behave very strangely.
For example:

[size=2](meshop.getMapFace mymesh 1 myfaceindex)[i][/size]

[size=2]returns a diferent vertex index than:[/size]

[size=1][size=2][color=white]modif.unwrap.getvertexindexfromface f i[/color][/size][/size]
[size=1][size=2][/size][/size]
[size=1][size=2]Can someone explain how this thing works?[/size][/size]
[size=1][size=2]Why do methods from meshop return different indices than the unwrap modifier?[/size][/size]
Is there a way to clean dead vertices?

[size=1][size=2]Thanks!
[/size][/size]