3 research outputs found
Computer aided modelling to simulate the biomechanical behaviour of customised orthodontic removable appliances
In the field of orthodontics, the use of Removable
Thermoplastic Appliances (RTAs) to treat moderate malocclusion
problems is progressively replacing traditional fixed
brackets. Generally, these orthodontic devices are designed
on the basis of individual anatomies and customised requirements.
However, many elements may affect the effectiveness
of a RTA-based therapy: accuracies of anatomical reference
models, clinical treatment strategies, shape features
and mechanical properties of the appliances. In this paper, a
numerical model for customised orthodontic treatments planning
is proposed by means of the finite element method.
The model integrates individual patient’s teeth, periodontal
ligaments, bone tissue with structural and geometrical
attributes of the appliances. The anatomical tissues are reconstructed
by a multi-modality imaging technique, which combines
3D data obtained by an optical scanner (visible tissues)
and a computerised tomography system (internal tissues).
The mechanical interactions between anatomical shapes and
appliance models are simulated through finite element analyses.
The numerical approach allows a dental technician to
predict how the RTA attributes affect tooth movements. In
this work, treatments considering rotation movements for a
maxillary incisor and a maxillary canine have been analysed
by using multi-tooth models
Customised 3D tooth modeling by minimally invasive imaging modalities
Dental panoramic tomography represents a standard imaging modality in dentistry since it provides a convenient and inexpensive method to visualize anatomic structures and pathologic conditions with low radiation doses. However, this technique does not provide comprehensive 3D geometries of dental shapes which are conventionally demanded to computerised tomography (CT) techniques. In this paper, a tooth reconstruction process is presented by integrating patient-specific information with general dental templates. A 2D panoramic radiograph and the digitised patient plaster cast are used to customise both shape and orientation of teeth templates thus allowing a consistent 3D tooth reconstruction with minimally invasive imaging modalities. The proposed methodology does not make any assumption about the tomographic device used to collect the panoramic radiograp