Measurement of normal and pathological mandibular and temporomandibular joint kinematics: a systematic review

Abstract Temporomandibular joint (TMJ) and mandibular motion plays a pivotal role in the function of the dentition and associated hard and soft tissue structures, and facilitates mastication, oral communication and access to respiratory and digestive systems. Quantification of mandibular kinematics facilitates the evaluation of TMJ function, and is clinically relevant in cases of prosthetic rehabilitations, TMJ disorders, osteoarthritis, trauma, tumour resection and congenital abnormalities which are known to directly influence mandibular motion and loading. The objective of this systematic review was to critically investigate published literature on historic and contemporary measurement modalities used to quantify mandibular and TMJ kinematics with six degrees of freedom in vivo. The electronic databases of Scopus, Web of Science, Medline, Embase and Central were searched and one hundred and nine relevant articles identified. Publication quality was documented using a modified Downs and Black checklist. Axiography and ultrasonic tracking are commonly employed in the clinical setting due to their simplicity and capacity to rapidly produce low-fidelity mandible motion data. Magnetic and optoelectronic tracking have been used in combination with dental splints to produce higher measurement accuracy while minimising skin motion artefact, but at the expense of setup time and cost. Four-dimensional Computed Tomography provides direct 3D measurements of mandible and TMJ motion while circumventing skin motion artefact entirely but employs ionising radiation, is restricted to low sampling frequencies and requires time-consuming image processing. Recent advances in magnetic tracking using miniature sensors adhered to the teeth in combination with intraoral scanning may facilitate rapid and high precision mandibular kinematics measurement in the clinical setting. The findings of this review will guide selection and application of mandibular and TMJ kinematic measurement for both clinical and research applications.