In the following video, 3D printing specialist Steve Heller asks Terry Wohlers, President of Wohlers Associates, which publishes Wohlers Report 2014, about the biggest takeaways from the Rapid 3D printing conference, as well as the biggest drivers of demand in metal 3D printing. During the segment, Wohlers highlighted two areas driving demand for metal 3D printing: medical and aerospace.

According to Wohlers, more than 90,000 hip cups have been 3D-printed to date, and more than 20,000 dental copings are being produced from 3D printers every day of the week. On the aerospace front, Airbus will be introducing a 3D-printed cabin bracket that secures elements of the cabin, like a lavatory, to the airframe, and will soon be flying on its upcoming A350.

In terms of the investing landscape, 3D Systems (DDD 0.57%) has made considerable efforts to attack the overall rise of 3D printing in healthcare as well as aerospace with its line of direct metal 3D printers. Since acquiring metal 3D printer Phenix Systems in mid-2013, 3D Systems has oversold its direct metal 3D printing manufacturing capacity in every quarter. The company is currently in the process of bringing a second manufacturing plant online to meet growing future demand.

Going forward, current and prospective 3D Systems investors should continue monitoring the uptake of metal 3D printing for medical and aerospace applications because it may continue to provide a strong growth avenue for the company. Additionally, investors should recognize that 3D Systems is a diversified 3D printing company and generates revenues from a host of different applications outside of medical and aerospace. In other words, investors considering buying a position in 3D Systems should also consider the multifaceted approach that 3D Systems has employed.

A full transcript follows the video.

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Steve Heller: Moving on now, you travel the shows. You've been all over the world, traveling to these conferences. Rapid 2014: What is your biggest takeaway from this year's conference?

Terry Wohlers: The biggest takeaway, I'd have to say, would be the number of people -- more than double the number of people at this event compared to one year ago.

Heller: Wow.

Wohlers: So that, the number of new people as well, and then I'd say the overall enthusiasm and the excitement; that people are just so engaged, and they want to be a part of this industry, and many are.

There's new opportunities developing and they want to look at, does it make sense for them as an individual, or their company? A lot of people are carrying two business cards. One is their company, and one is their own, where they are entrepreneurs and they want to be a part of this on their own as well.

Heller: Very good. So the biggest theme, you said, would be interest at an all-time high, focus on metals as well. Would you say aerospace is driving most of the metal demand right now?

Wohlers: Well, two areas. Really medical -- and a part of medical would be dental. Both are building many medical parts.

Just one application would be an acetabular cup. That's a hip cup, which mates with the hip stem and ball, that forms the joint in your hip. Those cups are being made in quantities of tens of thousands. More than 90,000 have been produced to date. Those would be made in solid titanium, so the orthopedic industry, they're embracing this and using it.

The dental industry, more than 20,000 copings every day of the week are being produced by additive manufacturing. A coping is the main body of a crown or a bridge, so if you have a rotten tooth and you have it removed.

Then aerospace, absolutely. Airbus will be flying soon on the A350, their new aircraft, these cabin brackets. They're these very complex brackets that hold the main body of the aircraft. They connect the cabin, like the lavatories and the galleys, to the airframe.

Traditionally they're machined. There's a lot of waste and scrap, and they're heavy, and they're expensive. Now they're doing them additively [with 3D printing], producing these and saving tremendous amounts of material, and they're reducing weight, too. If you're an airline, like with Lufthansa or United, that's very important. They'll buy a lighter aircraft over a heavier one, because they save fuel.