Try this:

1. Enable the looptools addon if you haven't already

2. Snap the cursor the the outermost vert, you'll need to mark this position for a later step

3. Select the line of verts and use the appropriate front/side ortho view so you are looking directly at the edge. Hit W key > Looptools > Flatten and set the mode to "from view". That will arrange all the verts to a straight line, but it will be at the average location instead of the farthest. Luckily, we marked the farthest point in step 2...

4. Hit shift+s and select "selection to cursor (offset)". This should bring everything forward to the outermost point.


Not the simplest or most direct way, but should get the job done without having to move each vert individually or guess at the position.