Embodiments of the present invention provide devices (tags), systems, and methods to determine structural integrity and other states of orthodontic-elements, such as orthodontic-brackets, orthodontic-archwires, orthodontic-expanders, orthodontic-elastic-bands, and orthodontic-power-chains, to name a few, in a non-invasive and contactless way, with respect to monitoring and using comparatively safe and/or low energy electromagnetic radiation, such as radio waves. Negligible-sized backscatter-tags with sensors are implanted in or attached to such orthodontic-elements. Such arrangements may permit monitoring of forces acting on teeth by various orthodontic-elements. Using backscatter imaging technology, the structural integrity and other states of the orthodontic-elements may be monitored which may allow non-invasive and contactless detection of problems such as cracking, bending, excessive pressure, improper temperature, and/or the like. Additionally, initially unknown locations of the implanted negligible-sized backscatter-tags with sensors may be readily determined upon a given scanning (reading) session and thus mapped to provide an effective image of the orthodontic-elements.