Complements of Curves in Closed Surfaces: Homeomorphic?

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Hi, let ## \alpha, \gamma ## be non-isotopic curves in a compact, oriented surface S. There is a result to the effect that ## S-\alpha## is homeo. to ## S- \gamma ## . This is not true as stated; we can , e.g., remove a disk (trivial class) in a copy of S and then remove a meridian ( a generator of ## H^1 (T^2) ##). Does anyone know the corrected result? This is not true either if we only remove essential curves. It seems like if ##\alpha, \gamma## actually _were_ isotopic , then this would be true. Or maybe if they were homologous?
Thanks.
 
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I seem to remember coming across the result you are looking for in Farb and Margalit's Primer on Mapping Class Groups, in chapter 1, if I am not mistaken. I think maybe they call it the change of coordinates principle.
 
http://www.math.ethz.ch/~bgabi/Farb%20Magalit%20January%202011%20version.pdf
 
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Thanks; in case anyone else is interested, here it is, towards the bottom of p.39:

There is an orientation-preserving homeo. of a surface S taking one s.c.c * ## \gamma## to ## \beta## iff the
corresponding cut surfaces ##S -\gamma ## , ##S- \beta ## are homeomorphic.

*s.c.c: Simple-Closed Curve.