[Reactive capacity of animal and human condylar cartilage at the cellular and molecular levels in the light of a cybernetic concept of facial growth]

Effectiveness of intra- and extraoral aids to the bionator. A controlled study within the scope of the "Wuerzburg concept"

A bimaxillary device is effective only if the therapeutic position of the mandible is maintained for as long a period as possible by day and night, i.e. the lower jaw cannot "drop" from the construction bite position. One simple means of preventing the mandible from dropping out of the bimaxillary appliance during sleep and thus of ensuring adaptation of the muscles and of the joint structures during the night without impairing active adaptation during daytime functions (speaking, swallowing) is being used at Wuerzburg University Department of Orthodontics: In connection with anterior traction, which anchors the bimaxillary appliance to the maxilla, attachments are fixed to the mandibular canines or first premolars, so that the mandible is kept in the therapeutic position during the night by means of elastics. Besides the description of this method, the results of a clinical study on its effectiveness are presented in this paper. In the experimental group (20 Class II/1 patients) treated with the combination of bionator with anterior extraoral traction and up-and-down elastics, the increase of the SNB angle and accordingly of the ANB angle was twice as great as in a control group treated only with bionator and extraoral traction without additional securing of the mandible.

[A clinical study of the effect of a rigid open activator (ROA) in the treatment of Angle class II.1]

The study introduces a maximally weight and volume reduced rigid open activator (ROA) for wear by patients with Angle class II.1 deformities. The activator is worn from about the age of 9 until the end of the eruption of the permanent canines and the first and second premolars. Intensive wear of the activator leads to regular occlusion after only 4 months. Cephalometric parameters at the beginning of treatment compared with those following regular occlusion document and illustrate the impressive adaptation of the masticatory system achieved through wear of the ROA.