Restoration of the anterior guide with the fixed prosthesis

The anterior guide is a functional entity, which is part of the set of guidance provided by the dento-dental joints to the mandibular kinematics, essential for the establishment of harmonious occlusal relations. The anterior guide is a key to understanding and reconstructing the occlusion, playing both a role of protecting the posterior teeth and guiding the functional movements of the mandible. Currently, it also represents an “exteroceptive feeler” creating a cone of access to the occlusion in intercuspation. The restoration of functional and protective anterior guidance is therefore essential for the balance of the masticatory system. This rehabilitation can only be achieved by examining and accurately diagnosing the occlusion relationships maintained by the anterior teeth, associated with a reasoned therapeutic approach validated by a test phase. After a brief description of the anterior function and its role, this article aims to detail, through a clinical case, the procedure to follow for the restoration of a functional anterior guide.

In Vitro and In Vivo Assessment of a New Workflow for the Acquisition of Mandibular Kinematics Based on Portable Tracking System with Passive Optical Reflective Markers

Clinical use of portable optical tracking system in dentistry could improve the analysis of mandibular movements for diagnostic and therapeutic purposes. A new workflow for the acquisition of mandibular kinematics was developed. Reproducibility of measurements was tested in vitro and intra- and inter-rater repeatability were assessed in vivo in healthy volunteers. Prescribed repeated movements (n = 10) in three perpendicular directions of the tracking-device coordinate system were performed. Measurement error and coefficient of variation (CV) among repetitions were determined. Mandibular kinematics of maximum opening, left and right laterality, protrusion and retrusion of five healthy subjects were recorded in separate sessions by three different operators. Obtained records were blindly examined by three observers. Intraclass correlation coefficient (ICC) was calculated to estimate inter-rater and intra-rater reliability. Maximum in vitro measurement error was 0.54 mm and CV = 0.02. Overall, excellent intra-rater reliability (ICC > 0.90) for each variable, general excellent intra-rater reliability (ICC = 1.00) for all variables, and good reliability (ICC > 0.75) for inter-rater tests were obtained. A lower score was obtained for retrusion with “moderate reliability” (ICC = 0.557) in the inter-rater tests. Excellent repeatability and reliability in optical tracking of primary movements were observed using the tested portable tracking device and the developed workflow.

Additive Manufacturing and Dentistry: Designing a Semi-Physiological Articulator

Introduction: The use of second generation semi-adjustable articulators for the reproduction of the mandibular kinematic often proves to be a technical and time constraint for the dentist. Therefore, its use, however essential within the dental office, is frequently forsaken. Materials and methods: The possibility of reproducing complex anatomical forms using rapid prototyping technologies can induce a more attractive and effective use of such a modified articulator. Results & Conclusion: Indeed, these replicas substitute for mechanical adjustments and thereby make the metrology on the patient an unnecessary element, both sources of the approximation of the kinematic. The aim of this study is to report on designing and manufacturing a semi-physiological articulator and on its pertinence through the comparison of the mandibular kinematics movement reproducibility on the two types of articulator.