Originally Posted by
avaldes
Not that it is ANY of my business, but in engineering it is common practice to roll the revision of a part for a minor change. A roll to the part number is reserved for major changes. Obviously in the world of Xray engineering, the V2 is a minor change.
We have 100's of thousands of manufactured parts that we engineer at my employer. We do revisions to parts all the time and keep the same part number as long as the part is functionally interchangeable with the old version with no other changes. In this case it could go either way (new part number or not) and Xray decided to not to change the part number which would indicate to me that the new V2 part is functionally interchangeable with the old one.
It's unfortunate that you would need to change both arms if you break one old one and replace it with one new one but that's the way it was done. And, I would expect that retailers only stock one version of the same part number which would be the V2 version.