Indications for Use:

The Bionator or removable functional appliance is used for Pendulum anchorage in those brachyfacial types with short mandibular corpus length. It serves to maintain the distalized molar position while developing the lower arch forward.

Figure 24. Bionator in place following expansion and distalization with a Pendex Appliance. A clear retainer used for interim stabilization. The molars are now in a super Cl III molar relationship.

Figure 25. Occlusal view of the upper arch while the Bionator is being utilized. An acrylic block fills in the space between the upper deciduous and permanent molars (although a small clip-spring can also be used). This is adjusted as the upper buccal segments erupt distally.

Figure 26. Facial and occlusal changes following Pendex and Bionator wear. Total treatment time to date: 13 months. Upper buccal segments are being retracted to severely overcorrected molar position. A very dramatic response in this severe Class II, D I malocclusion.

Technique:

After the Pendulum Appliance is removed, impressions and construction bite for the Bionator are made. A second impression of the upper arch is taken and a clear retainer made and placed. The Bionator is fabricated with a clip spring mesial to the molar or the bicuspid-molar space is filled with acrylic. With the Bionator in place, the molar will be in a full step (almost a full tooth) Class III relationship. This allows the upper buccal segments to erupt in more distal positions. The space is maintained until full eruption of the dentition and then released for space closure.

Considerations:

The functional appliance requires cooperation, so it is intended for those with high responsibility levels.