1993 Honda Civic

This could be normal wear. But did you also check your flex-plate for the same wear?

The flex-plate material is made from a harder metal than the starter gear teeth, but it could also wear to the point of needing replacement. And sometimes one/more of the flex-plate teeth will break off and cause the starter gear teeth to grind away.

If you haven't already installed a new starter, check those teeth first.

If your starter gear teeth are completely ground down, then you shouldn't assume this is normal wear, even though it very well may be.

Because once the starter's teeth are bad, they could also make the flex-plate teeth bad. And connecting a brand new starter to a bad flex-plate will quickly destroy the teeth on the new starter.

To check the flex-plate, look under the motor and into the same spot where the starter's teeth engage the flex-plate (no need to remove the tranny). You'll need to turn the engine over by hand to look at all of the teeth.

To do this, first disconnect the negative bat terminal. Then you'll need a half-inch breaker bar (24" long) and a large socket that will fit over the nut on the crankshaft's pulley. Remove the spark plugs from each cylinder and turn the engine over a little at a time until you see all of the teeth.

If there's any missing/broken/chewed up, then replace the flex-plate.