Combined tomography and conventional impression with notch system to fabricate prosthesis with palatal obturator in patients with severe limited mouth opening

In oral cancer therapies, surgery or radiotherapy frequently result to maxillary defects and limited mouth opening (LMO). For prosthetic rehabilitation, these sequelae present significant challenges to achieving accurate impressions. Intraoral scanners (IOS) are unsuitable due to the size of the scanner tips, while conventional impression techniques risk tearing during tray removal. Additionally, cone-beam computed tomography (CBCT) alone, without superimposed IOS data, lacks the precision required due to insufficient tissue precision and artefacts. To address these limitations, a novel hybrid technique combining CBCT and conventional impressions was presented in 3 patients. A 3D-printed model was created from CBCT data, which serves as base for fabricating a palatal plate with notches. This plate is used to capture a conventional impression of the dentition, and the two components are aligned extraorally using notches. This approach ensures capture of hard and soft tissues while reducing patient discomfort with severe LMO during the impression process.