Abstract: Systems and methods for rapidly and reliably determining an arch with of a patient's dental arch. A patient's dentition may be scanned and/or segmented. Arch width may be determined between points of intersection on the occlusal surface and a long axis of each tooth between one or more of: canine, first bicuspid, first primary molar, second bicuspid, second primary molar, and permanent first molar. Arch widths of different modified versions of the patient's dentition may be dynamically compared the patient's starting dentition, or to each other, and may be dynamically updated as the user modifies or switches between one or more 3D models of the patient's dentition.

Abstract: Provided herein are systems and methods for determining hook and or positioning feature placements during dental treatment planning. A patient's dentition may be scanned and/or segmented. A target tooth may be identified. Hook and or positioning feature placement may be determined based on satisfying manufacturing and clinical constraints. The hook or positioning features can be input into a dental treatment planning system.

Abstract: Orthodontic devices such as aligners, palatal expanders, retainers, and dental implants can be used to adjust the position of teeth and to treat various dental irregularities. To help the clinician or doctor (i.e., orthodontist) design and plan the subject's treatment plan, a 3D digital model of the subject's teeth, dentition, and gingiva can be constructed from a 3D scan of the subject's mouth, teeth, dentition, and gingiva. The 3D model of the subject's teeth and dentition can be displayed graphically to the doctor on a display using a computing system with memory and software.

Abstract: Orthodontic and/or dental treatment planning methods and apparatuses. In particular, described herein are methods of generating a plurality of potential treatment plan variations for the concurrent and interactive review of the treatment plan variations. Each variation may be optimized to best address the user's treatment goals, as well as approximating as closely as possible an ideal or target final position. Also described herein are orthodontic and/or dental treatment planning methods and apparatuses that allow a user to form, modify, and select a treatment plan from a plurality of different treatment plans, in real time.