Differences between three different mandibular motion recording systems

Recently, real-time mandibular kinematics acquisition systems have been introduced in dentistry. These tools, capable of detecting condylar trajectories, represent valuable support in the diagnosis and treatment planning of temporomandibular disorders (TMD). However, the use of different technologies and anatomical landmarks can lead to discrepancies in the recorded trajectories. The mandibular condyle is a superficial structure whose precise localization may vary depending on the operator’s skill, thus affecting the reliability of the acquired data. This study aimed to compare three widely used systems—Modjaw, Itaka, and Zebris—by analyzing the kinematic traces obtained from a sample of adult subjects, to assess their clinical reliability. Twenty adult subjects (20–45 years old) undergoing orthodontic-gnathological evaluation were included. Each was examined using all three systems, strictly following the manufacturers’ instructions. Mandibular movements recorded included opening, closing, protrusion, and right and left lateral excursions. Data regarding the amplitude and pattern of the trajectories were statistically analyzed using Excel and StatPlus, calculating correlations between the systems. Differences emerged in ease of use, patient comfort, anatomical landmark reliability, and graphical output. Further practical differences were observed in equipment costs and software update policies. Preliminary data analysis suggestted possible discrepancies among the systems, pending statistical confirmation. This study provided a comparative evaluation of three digital systems for mandibular motion analysis and contributed to the advancement of more accurate diagnostic and therapeutic approaches in patients with TMD.