Various different Pendulum appliances have been presented and articles written. However, the appliance shown in the photo above was developed to make improvements on previous versions. The aim was to develop the simplest, easy to handle appliance that would allow the patient to maintain good oral hygiene. It was also essential to obtain a most effective distalization.

Components:

1. Base with the attachment tubes
2. Anchorage wires
3. Bite planes
4. Molar bands with Goshgarian tubes
5. Preformed distalizing springs

The items 1 to 3 could be classed as the anchorage components and the items 4 and 5 as the active parts of the appliance.

Clinical conditions for treatment with the modified Pendulum Appliance:

• The wisdom teeth must be removed.
• The root típs of the molars should not have contact with the base of the sinus. Prior to treatment an O.P.G. x-ray or if available a three dimensional x-ray should be taken.

Lab Instruction

Prior to the manufacturing of a Hawley retainer an alginate impression and a plaster model must be made. Firstly, the attachment wires are bent using an .032“ ( 0.8mm)spring hard wire and positioned on the first and second premolars.

Note:
Dependant upon the patient’s case it may be necessary to bond deciduous teeth or even the cuspids. The occlusal parts of the wires should be fixed with wax onto the model.
The retention segments should have a minimum of .040“ (1mm) to the surface of the model.

To insert the distal glide springs two attachment tubes must be fixed in the distal area of the shield.

Note:
To help to achieve the correct positioning the attachment tubes can be held in place with wax on little wire pieces with a diameter of .032“ ( 0.8mm).
The tubes must be fixed parallel to the vertical and saggital direction of the movement of the molars.
It is also important to check the distance of .040“ (1mm) to the surface of the model.

The following procedure is identical to making a Hawley retainer. After the correct positioning with wax of the attachment wires and the tubes, the base must be coated with orthodontic acrylic (alternative: light cure acrylic). For better control of oral hygiene during treatment it is suggested to make the base out of clear acrylic. A better oral hygiene will be achieved when the distal third of the base has a . 040” (1mm) space between the base and the model. Once this has been achieved, the anchorage unit of the appliance is finished.

The pre-manufactured distal glide springs can be adapted either in the lab or chair side with the patient. To insert these springs into the anchorage unit, the springs must be inserted in the tubes they can be removed at any time for activation. During treatment replacement springs can be inserted should additional distalization of the molars be required. The length of the springs needed is determined by the amount of distal movement required.

The amount of activation will be equivalent to the length of the goshgarian tube. When shortening the springs ensure that the mesial stop of the relaxed springs is in the area of the distal end of the goshgarian tube. If the end of activation has been reached and additional distalization is required, adapt a new set of springs as mentioned above.

The shape of the palate must be also taken into consideration.

Case Photos

The lab process is now finished and the appliance can now be inserted in the mouth of the patient. The modified Pendulum appliance must be fixed with composite in the occlusal area of the premolars. The composite should be formed as bite plane to avoid occlusal interference in the molars region.

Note:
A bonding material containing fluoride is recommended such as Transbond Plus, 3M Unitek or Ultra Band Lock, Reliance.
It is very important to form the bite blocks very carefully in order to achieve good contact points in the area of buccal segment.
As the distalizing springs are only held in place by the attachment and the goshgarian tubes it is necessary to fix the springs with separating elastics.

After a two -three month period according to 5th movement of the teeth, a new activation can be done. Special attention must be given on oral hygiene during treatment, and it is recommended to have the patient visit the hygienist regularly.

Written by:
Dr. Hatto Loidl
Berlin, Germany