A straightforward protocol for designing an interim hollow shell with open-source software.

BACKGROUND: An interim hollow shell (IHS) is a temporary prosthesis that adapts like a cap over a prepared tooth abutment. Using a conventional protocol to fabricate IHS from casts of the initial situation or the wax-up can be challenging, time-consuming, and sometimes frustrating. A digital workflow makes this process quicker and more convenient. The IHS must be first designed with computer-aided design (CAD), then fabricated with computer-aided manufacture (CAM). Proprietary dental software is commonly used for the design process but needs to be purchased. OBJECTIVE: To describe a step-by-step technique for designing an IHS for posterior relining with open-source software. METHODS: This paper describes a straightforward procedure to design an IHS from a dental scan of the initial situation or a digital wax-up for an esthetic and functional temporary rehabilitation. RESULTS: An IHS can be quickly designed using open-source software by copying an existing restoration or a conventional or digital wax-up. Then, the design can be 3D printed using a biocompatible resin. CONCLUSIONS: The clinician can use open-source software to design IHSs, which are then 3D printed using a biocompatible resin. CLINICAL RELEVANCE: The clinician can design IHSs from a dental scan of the initial situation or a wax-up using open-source software by following the step-by-step protocol outlined in this paper. The restoration can then be 3D printed using a biocompatible resin.