A person on the Geomagic forum (Alibre) began a spiral bevel pinion, using tooth profile generated from an excel file (pinion Macros) from here:
http://www.spiralbevel.com

I completed the 8 remaining Boolean difference cutouts using MoI here:

http://forum.alibre.com/viewtopic.php?f=10&t=17393&p=109577#p109577

The tooth profile cutout for the matching gear is also generate-able from the excel file, also by using the gear Macros.
It remains to draw up a gear blank, and Boolean difference away the 20 tooth cutouts.

I used excel 2010, and had to enable the Developer tab, and enable the Macros. (They should be disabled afterwards for security.)

The spreadsheet is protected from entering other gear ratios (tooth numbers).
Other tooth numbers generate different tooth shapes.
(The basic program costs the same as MoI. Tooth Contact Analysis costs more.)
I would expect that the purchased program is more advanced. (?)
The professional gears are manufactured with CNC machines.

The two Macros generate the IGES tooth cutout files, which MoI can import.
The Macros code is password protected, copyrighted, and is fairly lengthy.

There is also a Crown Gear (= face gear) excel spreadsheet demo.

- Brian