Nataly Zambrana1,*; Stefano Pieralli2; Ilia Fomenko3; Issam Dakir4; Silvio Valdec5; Newton Sesma1

1Prosthodontic Department, University of Sao Paulo, Sao Paulo, Brazil; 2Department of Prosthetic Dentistry, Center for Dental Medicine, Medical Center, University of Freiburg, Freiburg, Germany; 3Private practice, Sumy, Ukraine; 4Private practice, Beni Mellal, Morocco; 5Clinic of Cranio-Maxillofacial and Oral Surgery, Center of Dental Medicine, University of Zurich, Zurich, Switzerland

Background: Long-term success of the dental implant-prosthetic complex is correlated to a biomechanically controlled occlusion. By upgrading from a 3D (static) to a 4D (dynamic) virtual patient reconstruction individual information on the temporomandibular joint (TMJ) and occlusal patterns can be transferred to virtual or analogue articulator systems. However, jaw mobility tracking and analysis systems are currently cost-intensive and not worldwide accessible.

Aim/Hypothesis: This technique presentation describes a novel straightforward method for chairside record and analysis of mandibular kinematic by means of a smartphone and an open-source 3D creation suite.

Material and Methods: Intraoral scans with standard tessellation language (STL) format and a cone beam computed tomography (CBCT) including the TMJ and exported as DICOM (digital imaging and communications in medicine) dataset, are superimposed. Thereafter, visual fiducial markers boards (VFMB) are adapted onto the buccal side of the patient´s teeth and a mobile phone camera with 4K resolution is used to record the mandibular excursions with 60 fps in ambient lighting. A silicone impression of the occlusal bite with integrated VFMB is digitized and aligned to the intraoral scans and CBCT using an add-on module of an open source software. To integrate the mandibular motion a specific algorithm is used to decode the three-dimensional positions of the VFMB and provide a text (txt) file with all 3D coordinates.

Results: Patient-specific parameters as the anterior condylar guide, the Bennett angle, the lateral-excursion angle as well as the maximal mouth opening are reported in millimeters and angles and subsequently transferred to a virtual articulator system. Finally, an individualized dynamic virtual patient model is created and used to analyze both, TMJ function and occlusion patterns.

Conclusion and Clinical implications: Integrating the individual mandibular dynamics to the static virtual patient can be a useful tool for communication, diagnosis and therapy. This technique presents an open-access alternative to the expensive devices available on the market. Rigorous validation process is needed prior to clinical use.

Disclosure of Interest: None Declared

Keywords: biomechanical stability, digital workflow, prosthetic complications