Questions: Craniomandibular dysfunctions (CMD) are dysregulations of the chewing organ and adjoining structures, which can lead to destruction of hard and soft dental tissues, joint cartilage, decreased chewing function, and pain, thereby massively reducing wellbeing and quality of life. The treatment of CMD requires accurate and objective diagnostics to enable a successful interdisciplinary treatment. Conventional diagnostics cannot completely detect the temporomandibular joint in its own complexity by technical restriction. In addition, due to a high proportion of "manual labour", human errors and diagnostic variances cannot be excluded (1). The aim of the present study was to evaluate a full digital workflow for craniomandibular dysfunction (CMD) diagnostics, including intraoral scans, digital volume tomography, digital motion tracking, and treatment with a 3D-shaped bite splint. Methods: This prospective study included n=19 adult patients (8 men, 11 women) suffering from CMD, who met the inclusion criteria and consented to the therapy and the use of their data. Inclusion criteria were as follows: - presence of a craniomandibular dysfunction requiring treatment - no previous splint therapy - no primary temporomandibular joint disease or general underlying disease that could be the cause of the pain or could influence the therapy outcome (e.g. rickets, Parkinson's disease, osteoporosis, psychosomatic diseases, neuralgias, and neuropathies). Prior to treatment, ethical approval was obtained by legal agency (EK 213062018). 3D diagnostics and data matching were performed, on the basis of which a 3D bite splint was designed and produced (SICAT, Bonn, Germany; Polymethylmethacrylat astron^® Clearsplint^® CAD/CAM, Schütz Dental GmbH, Rosbach, Germany). Patients were evaluated pre- and post-treatment and every 6 weeks up to 6 months by clinical analysis, splint adjustment, and questionnaire. Descriptive analysis and statistics were performed using MS Excel (Version 16.0, Microsoft Corporation, Redmond, USA). Results: Splint therapy led to a significant reduction in subjective complaints in 89% (n=17) of patients, whereas only 11% (n=2) reported unchanged complaints. 74% (n=14) of patients preferred digital impressions and milled bite splints; the other 26% (n=5) did not indicate a special preference. The majority of digital designed bite splints showed a satisfactory initial fit (58%//n=11) and 32% (n=6) could be fitted after minor adjustments. Conclusions: The digital workflow for CMD treatment, analysed in this study, showed a significant reduction in working time by a high proportion of digitization and automation combined with a high level of patient satisfaction and accuracy of splint fit. Nevertheless, the use of digital volume tomography did not improve diagnostics (2) and should be viewed critically in this context. Keywords: CMD treatment, 3D-shaped bite splints, digital workflow, economic efficiency

A patient with arthrogenic temporomandibular dysfunction (TMD) complaints presented. In addition to a clinical diagnosis, an instrumental one with Sicat Function (Sicat) was performed. For this purpose, movements of the mandibular function were recorded with an ultrasonic-based measuring system (JMT+) and correlated with cone beam computed tomography (CBCT) image data. A reference tray (FusionBite) ensured spatial agreement. In addition, full-arch scans taken with the Cerec Omnicam intraoral scanner (Dentsply Sirona) were matched to the CBCT data. From the movement data, a biomechanically optimized joint position was determined, for which an occlusal splint was milled. Subsequently, the functional result achieved was retained with computer-aided design/computer-aided manufacturing (CAD/CAM) temporary restorations and tabletops and was monitored with Sicat Function until delivery of the final rehabilitation. To this end, the movements were tracked with the JMT+ after each treatment step. The reference tray was successively adapted and augmented so that the original jaw relation in the FusionBite could be maintained, which guaranteed comparability with the initial situation without the need for an additional CBCT image. Sicat Function has proven to be an excellent system supporting a digital workflow in situations where controlled bite-position changes are indicated in patients with arthrogenic TMD complaints. Keywords: instrumental digital functional diagnostics, Sicat Function, CAD/CAM, Cerec, digital workflow, TMD diagnostics, digitally guided bite-position change