Abstract: Methods for designing and fabrication of a series of apparatuses for expanding a patient's palate (“palatal expanders”). In particular, described herein are methods and apparatuses for forming palatal expanders, including rapid palatal expanders, as well as series of palatal expanders formed as described herein and apparatuses for designing and fabricating them.

Abstract: A cancer detection model and a construction method therefor, and a reagent kit, relating to the technical field of cancer detection. The method comprises: performing whole genome sequencing on plasma free DNA to mine nucleosome distribution features, terminal sequence features, and fragment size distribution features that can be applied to cancer detection; constructing classification models of the three indicators to obtain prediction scores of each indicator for a sample; then integrating these scores using a logistic regression model, and adding copy number variation feature information to obtain an ultimate classification and prediction model.

Abstract: Palatal expander apparatuses for expanding a patient's palate (“palatal expanders”) and methods of using and making them. These palatal expanders may be configured to have a variable surface smoothness on one side (e.g., the lingual-facing surface) compared to the opposite side (e.g., the palatal-facing surface). These palatal expanders may be configured to have a varying thickness in the palatal region. These palatal expanders may be adapted for ease in removal by the patient or caregiver (e.g., including a hinged region and/or detachment region, and/or including a thinner buccal side then occlusal side, etc.).

Abstract: Methods and systems for dental treatment are provided. In some embodiments, a method includes receiving a plurality of treatment stages for repositioning a patient's teeth from an initial tooth arrangement toward a target tooth arrangement, where each treatment stage is associated with a target position for a tooth of the patient. The method can include determining, for one or more treatment stages, an overcorrected movement corresponding to an overcorrected position for the tooth that is different from the target position, where at least some of the one or more treatment stages include different magnitudes of overcorrected movements. The method can further include outputting fabrication instructions for one or more dental appliances corresponding to the one or more treatment stages, each dental appliance including an overcorrected tooth receiving cavity corresponding to the overcorrected position for the respective treatment stage.

Abstract: Systems, methods, and non-transitory computing device readable media for determining an individualized orthodontic treatment index. One embodiment includes generating a target dental model by modifying an initial dental model, graphically marking dental references on the target dental model including assigning contact points between adjacent first and second teeth of the target dental model, generating a treatment outcome dental model representing the patient's dentition after at least a portion of the orthodontic treatment has been completed, mapping the dental references marked on the target dental model to the treatment outcome dental model, and calculating an individualized treatment index score for the treatment outcome dental model according to one or more differences between the target dental model and the treatment outcome dental model.

Abstract: Series of apparatuses for expanding a patient's palate (“palatal expanders”), including rapid palatal expanders, wherein a left tooth engagement region and a right tooth engagement region are configured to add anti-tipping torque to at least one tooth. Left and right tooth engagement regions may include lingual surfaces with at least one lingual protrusion. Left and right tooth engagement regions may have buccally rotated cavities.

Abstract: A series of palatal expanders and methods of designing palatal expanders, including rapid palatal expanders, where outer occlusal surfaces of a palatal expander are shaped to conform to a geometry of corresponding teeth surfaces of the patient's lower jaw to provide occlusion between occlusal surfaces and the corresponding teeth surfaces.

Abstract: Orthodontic systems and related methods are disclosed for designing and providing improved or more effective tooth moving systems for eliciting a desired tooth movement and/or repositioning teeth into a desired arrangement. Methods and orthodontic systems include the generation of an overcorrection in the tooth-receiving cavities of an appliance worn in the dentition. The overcorrection may provide an improved and more accurately applied force or moment applied to a tooth. The overcorrected force or moment can move a tooth closer to a desired position than if not overcorrected as sufficient force can still applied to the tooth as it gets closer to the desired position. The overcorrected force or moment may also better target the root of the tooth where the biological response to tooth movement occurs. The overcorrection may be calculated in various ways as described herein.

Abstract: A dual aligner assembly including a plurality of aligners, including a first aligner and a second aligner. The first aligner has a first shape corresponding to a set of target tooth positions and applies an orthodontic force against a set of target teeth. The first orthodontic force generates movement of the set of target teeth to the set of target tooth positions. The second aligner has a second shape corresponding to a combination of current tooth positions of the set of target teeth, the set of target tooth positions, and a thickness of the first aligner. The second aligner partially encloses the first aligner and provides an anchor for at least a portion of the first aligner. Via the anchor, a combination of the first aligner and the second aligner provides an orthodontic force that prevents the set of target teeth from moving to unwanted tooth positions during orthodontic treatment.

Abstract: Palatal expander apparatuses for expanding a patient's palate (“palatal expanders”) and methods of making them. The apparatuses may include a pair of tooth engagement regions connected by a palatal region. A detachment region on at least one of the tooth engagement regions may be defined by one or more first vertical cut-out regions extending from a bottom of a buccal side toward an occlusal side of the tooth engagement region. The buccal side may be more flexible than the occlusal side so that the detachment region flexes when a removal force to release the palatal expander apparatus from the patient's palate is applied to the detachment region.

Abstract: Palatal expander apparatuses for expanding a patient's palate (“palatal expanders”) and methods of using and making them. The palatal expanders may include tooth engagement regions connected by a palatal region that is configured to apply force between the tooth engagement regions. At least a portion of the palatal region may be configured to have a clearance from the patient's mid-palatal region when the palatal expander is worn by the patient. The clearance between the palatal region and the patient's palate may decrease from the patient's mid-palatal region laterally toward the tooth engagement regions.

Abstract: A system and method for determining a center of resistance of a tooth may include receiving a 3D digital representation of an initial arrangement and a final arrangement of a patient's teeth and determining a 3D treatment plan. The 3D treatment plan may include a plurality of 3D stages for rearranging the teeth from the initial arrangement toward the final arrangement. The method may also include determining, in accordance with the 3D treatment plan, an intended movement of the teeth for each of the stages and deriving, using a 3D resistance model, an applied force system for achieving the intended movement of the teeth for each of the stages. The method may also include deriving 3D geometries of oral appliances for the stages in response to the applied force system. Various other systems and methods are also disclosed.

Abstract: Methods for fabricating dental appliances and associated systems are provided. In some embodiments, a method includes defining a plurality of object cross-sections of a dental appliance, and sequentially polymerizing the plurality of object cross-sections to create the dental appliance. The dental appliance can include an outer shell having a plurality of teeth-receiving cavities, and an inner structure coupled to an inner surface of the outer shell. The outer shell can have a first stiffness, and the inner structure can have a second stiffness less than the first stiffness. The sequential polymerization can include integrally forming the outer shell concurrently with the inner structure.

Abstract: A system and method for determining a center of resistance of a tooth may include receiving a 3D digital representation of an initial arrangement and a final arrangement of a patient's teeth and determining a 3D treatment plan. The 3D treatment plan may include a plurality of 3D stages for rearranging the teeth from the initial arrangement toward the final arrangement. The method may also include determining, in accordance with the 3D treatment plan, an intended movement of the teeth for each of the stages and deriving, using a 3D resistance model, an applied force system for achieving the intended movement of the teeth for each of the stages. The method may also include deriving 3D geometries of oral appliances for the stages in response to the applied force system. Various other systems and methods are also disclosed.

Abstract: Methods for designing and fabrication of a series of apparatuses for expanding a patient's palate (“palatal expanders”). In particular, described herein are methods and apparatuses for forming palatal expanders, including rapid palatal expanders, as well as series of palatal expanders formed as described herein and apparatuses for designing and fabricating them.

Abstract: A scan model that is a mathematical model to simulate an imaging process performed by an x-ray imaging device that created a two-dimensional x-ray image of at least one tooth is generated. The scan model uses an initial estimate of one or more parameters of the x-ray imaging device. The one or more parameters include a scan angle parameter indicative of a scan angle of the x-ray imaging device. A two-dimensional contour of a three-dimensional model is adjusted to cause a first component of the two-dimensional contour to approximately align with a second component of the two-dimensional x-ray image. The scan model is calibrated based on data obtained from adjusting the two-dimensional contour.

Abstract: A dual aligner assembly including a plurality of aligners, including a first aligner and a second aligner. The first aligner has a first shape corresponding to a set of target tooth positions and applies an orthodontic force against a set of target teeth. The first orthodontic force generates movement of the set of target teeth to the set of target tooth positions. The second aligner has a second shape corresponding to a combination of current tooth positions of the set of target teeth, the set of target tooth positions, and a thickness of the first aligner. The second aligner partially encloses the first aligner and provides an anchor for at least a portion of the first aligner. Via the anchor, a combination of the first aligner and the second aligner provides an orthodontic force that prevents the set of target teeth from moving to unwanted tooth positions during orthodontic treatment.

Abstract: Methods for designing orthodontic appliances for repositioning a patient's teeth are provided. In some embodiments, a method includes determining a movement path to move one or more teeth from an initial arrangement to a target arrangement, determining a force system to produce movement of the one or more teeth along the movement path, and determining an appliance geometry for an orthodontic appliance configured to produce the force system. The orthodontic appliance can include an outer shell comprising a plurality of teeth-receiving cavities and an inner structure positioned on an inner surface of the outer shell. The inner structure can have an elastic modulus different than an elastic modulus of the outer shell. The method can also include generating instructions for directly fabricating the orthodontic appliance using a layer-by-layer additive manufacturing technique.

Abstract: The present disclosure provides computing device implemented methods, computing device readable media, and systems for adjustment of tooth position in a virtual dental model. Virtual dental modeling can include detecting space and/or collision between posterior teeth of an upper jaw and posterior teeth of a lower jaw in a virtual dental model that has been set in a preliminary target position. An energy function can be defined including the space and/or collision, tooth root movement, and align points. Weights can be assigned for each variable in the energy function. A position of the posterior teeth of the upper jaw and the posterior teeth of the lower jaw can be adjusted in six degrees of freedom to minimize the energy function. The detection, definition, assignment, and adjustment can be repeated until the energy function converges. The weights can be adjusted to reduce the space and/or collision.

Abstract: Embodiments are provided for using an individualized orthodontic treatment index. One method embodiment includes receiving an initial virtual dental model from a first scan of a patient's dentition, modifying the initial virtual dental model to create a target virtual dental model according to a treatment goal, assigning a number of dental references to the target virtual dental model, receiving a treatment outcome virtual dental model from a second scan of the patient's dentition, mapping the number of dental references from the target virtual dental model to a treatment outcome virtual dental model, and calculating an individualized treatment index score for the treatment outcome virtual dental model according to one or more differences between the target virtual dental model and the treatment outcome virtual dental model based on the number of dental references.