For example, a graphite/epoxy (graphite fibers suspended in an epoxy matrix) lamina may be on the order of 0.127 mm thick. For the purpose of analysis, a lamina is typically modeled as having one layer of fibers through the thickness.
Minnesota allows dental therapists with direct supervision; and advanced dental therapists (ADT) with general supervision. ADTs may be dually licensed as an ADT and registered dental hygienist (RDH). Maine allows dental hygiene therapists (DHT) with direct supervision.
All 50 states mandate that orthodontists are licensed. Not only must they be licensed as dentists, states also require a separate orthodontist license. The dental license necessitates the passing of an exam, but those becoming orthodontists must complete more specialized schooling and possibly another exam.