Additively and Subtractively Manufactured Implant-Supported Fixed Dental Prostheses

Consensus Statement 1: (technology) Subtractive manufacturing (SM) technologies have been widely used for the fabrication of tooth-colored iFDPs, while AM techniques are increasingly being explored. At the present time, there are no comparative clinical data and six comparative in vitro studies.

Consensus Statement 2: (marginal and internal adaptation) Additive and subtractive CAM techniques have the potential to influence the marginal and internal adaptation of tooth-colored iFDPs on both prefabricated and customized abutments. Current data are insufficient to draw comparative conclusions. Based on three in vitro studies, directly comparing AM versus SM.

Consensus Statement 3: (mechanical properties) Both additive and subtractive CAM techniques can influence the mechanical properties (fracture loads and bending moments) of tooth-colored iFDPs. Current data are insufficient to draw comparative conclusions. Based on four in vitro studies, directly comparing AM versus SM.

1) Which CAD/CAM technology can be recommended for the production of an interim implant-supported fixed dental prosthesis?

For interim tooth-colored single implant crowns both additiveand subtractive manufacturing are viable techniques; however, for interim multi-unit iFDPs SM is currently recommended to minimize complications.

2) Which CAD/CAM technology can be recommended for the production of a definitive implant-supported fixed dental prosthesis?

For CAD/CAM definitive single- and multi-unit iFDPs subtractive manufacturing is recommended. Clinicians and dental technicians are encouraged to follow the rapid development of AM technology and related materials as significant improvements are expected in the near future.

3) Is CAD/CAM technology simple to use, once the devices are installed?

To achieve the intended results, it is necessary that both AM and SM technologies are applied with careful consideration requiring technical expertise and ongoing training. It is essential to follow specific manufacturing protocols and to maintain the devices.

1) I have heard about a new technology 3D printing. Would you recommend this technology for my implant crown?

3D-printed implant crowns can be recommended for temporary use. When it comes to implant bridges, we are still in the development phase. For definitive implant restorations, 3D printing cannot be recommended at the present time. Based on expert opinion.

2) I have heard that there is also the option of milling implant crowns. Are 3D-printed implant crowns cheaper and faster than milled ones?

As both technologies require manual post-processing adjustments, 3D printed restorations are not necessarily cheaper or faster. As the technology for printing implant bridges evolves it may prove to be faster than milling but it is too early to say or to recommend. Based on expert opinion.

3) Do 3D-printed implant crowns look good?

As with any other temporary implant restoration, with manual adjustments an esthetic result can be achieved. Based on expert opinion.

4) Have 3D resins proven to be safe?

3D printing materials for dental restorations are officially approved for use in the mouth. However, we can only recommend them for provisional/temporary implant restorations as only the results for shorter term use in the mouth are available. Based on expert opinion.