Sree S From your description, most places you mentioned '"Thingworx Platform and thingworx dashboard" which makes your question unclear. As Thingworx Platform is for IoT applications and Thingworx Studio AR applications.
Assuming your usecase is to develop a AR project - By saying looping in modelItem, do you mean showing interior objects of a 3D model? If so, yes ThingWorx Studio provides the feature, you can import the whole 3D model (follow the link for supported CAD files formats) and drag the "modelItem" widget on the desired parts, hide/unhide on button click or use JS script to accomplish the desired task.
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Topics include: AR/VR for Data Optimization, AR/VR for Security and Control, and AR/VR for Inspection.