Use of in-house, full-colour printed three-dimensional model for training in endoscopic periradicular surgery for molar radicular cyst.

reatment of molar radicular cysts is challenging and many olars may be removed if endodontic treatment is unsucessful. Conventional periradicular surgery of molars is not lways done, because of the technical difficulties and poor isualisation. Endoscopic periradicular surgery (EPS) has een introduced to avoid having to remove molars.1–3 If lling of the root canal is insufficient, we use EPS after ndodontic treatment. However, it is difficult to train oral urgeons to resect roots and fill the root of the molar preisely in a retrograde manner under endoscopic guidance, and training system has yet to be established. We have thereore created in-house, full-colour printed three-dimensional odel for training in EPS for molar radicular cyst. To produce the EPS training model, we used ZPrinter 450 Z Corporation, Burlington, MA, USA), which can print a ull-colour, three-dimensional model using a high perforance plaster-based composite that is cost-effective with ow waste. A full-colour, three-dimensional printer costs 1.9 imes the monochrome4, but the running costs are almost the ame. The vertical build speed is 23 mm/h and the build size 03 mm× 254 mm× 203 mm. In a patient with a molar radicular cyst, DICOM data ere transferred to Mimics 14 software (Materialize, Leuven, elgium) after computed tomography. The jaw, the molar ith the radicular cyst, and the root canal were segmented, nd the data were exported as an STL file to ZPrint softare (Z Corporation). The crown and roots were coloured, he root canals were produced as cavities, and then the three-