3D Metrology-Based Comparison of Functional Casts Made With Conventional Custom Trays and 3D-Printed Custom Trays in Completely Edentulous Maxillary Patients

Complete denture fabrication commonly relies on long-established conventional techniques. Custom trays are conventionally fabricated with chemically activated polymethyl methacrylate (PMMA) acrylic resin. Digital dentistry and additive manufacturing may provide alternative methods and materials for custom-tray fabrication, including PET-G (Polyethylene Terephthalate Glycol) filament.

In this study, functional casts obtained using conventional custom trays will be compared with functional casts obtained using digitally designed and 3D-printed custom trays. Anatomical casts will be made according to the anatomical impression technique fabricated in Type II gypsum, and digitized with an INEOS X5 bench scanner. The digital models will be processed in inLab software to remove undercuts and define the basal area outline.

For the conventional group, custom trays will be fabricated with chemically activated PMMA acrylic resin. For the printed group, custom trays will be digitally designed with a thickness of 3 mm and zero spacing, exported as STL files, and printed on an Adventurer 4 Pro printer using CREALITY CR-PETG thermoplastic filament, according to the manufacturer's parameters.

Functional impressions will be obtained using the technique recommended by the FOUSP Complete Denture Course and zinc-oxide eugenol impression paste. Functional casts will be fabricated in Type III gypsum, scanned, and exported as STL (Standard Triangle Language) files. The meshes will be compared in ZEISS Inspect software to quantify discrepancies between the test and reference meshes.