发音器官-医学.ppt

Articulators Definition: An articulator is a mechanical device used in dentistry to which casts of the maxillary (upper) and mandibular (lower) teeth are fixed, reproducing record positions of the mandible in relation to the maxilla. Types: Semi-adjustable articulator Fully adjustable articulator Anatomical articulator Adjustable articulator Disposable articulators Semi-adjustable articulator An articulator which is adjustable in one or more, but not all of the following areas: condylar angle, Bennett side-shift, incisal and cuspid guidance, and shape of the glenoid fossae and eminintiae. By nature, this sort of articulators use is only meaningful if the position of the maxillae are duplicated with respect to the hinge axis of the mandibular condyles. Normally this is achieved by the use of a face-bow. Fully Adjustable Articulator A fully adjustable articulator is used to reproduce more than one type of movement. It has a centric relationship, protrusive and retrusive movement and it has a left-right lateral maxillomandibular relationship . Anatomical articulator An articulator which attempts to reproduce normal mandibular movements during?mastication. Adjustable articulator An articulator that can be adjusted to accommodate the many movements and positions of the mandible in relation to the maxilla as recorded in the mouth. Disposable articulators Stone Base – An articulator system in which a model of the patient’s teeth for the maxilla and mandible are each mounted on a stone base with the use of dowel pins. The two are then brought together and articulated using a disposable articulator to act as the condyle. This requires having to make two pours. The first one is to get the model from the impression taken by the dentist. The other pour is for the stone base made from a rubber mold. Single-Pour - The single-pour system eliminates the need for a stone base. When the impression is poured up, it is directly mounted on a plastic base or tray that already