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Background: Unbalanced alterations of temporomandibular joint morphology were associated with unilaterally masticatory habits. Objective: This study aimed to investigate the effect of unilateral mastication on the remodelling of the temporomandibular joint using dynamic joint space. Methods: Twelve volunteers with non‐maxillofacial deformity and healthy temporomandibular joints were recruited. The 3D models of the mandible and the maxilla were reconstructed according to computed tomography. The subjects were asked to masticate French fries and peanuts unilaterally, which was recorded by a 3D motion capture system. The dynamic joint space during unilateral mastication was analysed. Results: During early closure, the joint space reduction on the non‐masticatory side was significantly greater than on the masticatory side (p <.05). During later closure, the joint space reduction on the non‐masticatory side was significantly lower than that on the masticatory side (p <.05). The difference in joint space reduction between both sides was greater than the French fries while masticating the peanuts. Conclusions: Unilateral mastication resulted in a different major pressure area on the bilateral TMJs. Therefore, unilateral mastication might be an essential factor in the bilateral asymmetrical remodelling of the TMJ. [ABSTRACT FROM AUTHOR]

The accuracy of the Newtonian model used in retrograde visceral revascularization (RVR) of hybrid surgery for thoracoabdominal aortic aneurysm (TAAA) hemodynamic simulation remains unclear. Noting that an appropriate blood viscosity model is a significant factor to capture hemodynamic changes in numerical studies. Therefore, both Newtonian and non-Newtonian blood viscosity models were adopted in this study to investigate the importance of hemodynamics when non-Newtonian blood property was accounted for in a patient-specific RVR simulation. The results revealed that disturbed flow and unfavorable WSS distribution can be observed in the anastomosis region under both blood viscosity models due to the retrograde flow pattern in the RVR model. However, although the non-Newtonian blood model has negligible effect on flow pattern and pressure drop, there were of significance quantitative and qualitative difference of local normalized helicity and wall shear stress distribution under pulsatile flow condition. In particular, the unfavorable WSS indicators distribution was better matched with a patient-specific follow-up report when non-Newtonian blood viscosity was accounted for. To conclude, the use of a Newtonian blood model is a reasonable approximation to obtain the general features of the flow field under steady flow condition. However, to study the hemodynamic parameters within retrograde flow under pulsatile flow condition, a non-Newtonian model may be more appropriate. [ABSTRACT FROM AUTHOR]

The formation of thrombosis is a major concern in the false lumen (FL) for post-TEVAR (thoracic endovascular aortic repair) patients. Blood stasis is one of the key factors which lead to the formation of thrombosis in the arterial systems. This study proposed a computational model for blood stasis, using a two-fluid principle to track the locations of blood residual over time. The current study applied this novel model to evaluate blood stasis and thrombosis potential in four patient-specific post-TEVAR FLs of type B aortic dissection, with their follow-up in-vivo observations two years after TEVAR. The locations and topologies of residual blood in the FL predicted by the model agreed well with the in-vivo observations of thrombus. In addition, the results corresponded better with clinical observations in terms of interpatient comparison of degree of thrombosis, compared with conventional hemodynamic parameters. The blood stasis model serves as a valuable addition to conventional metrics to better predict thrombosis potential. Collectively, these metrics can provide an efficient non-invasive method for evaluating blood stasis and thrombosis potential in arterial system, and useful guidance for clinicians' operative planning and postoperative evaluation. [ABSTRACT FROM AUTHOR]