Dr. rer. nat. Larissa Dloczik, Sellostr.22, D - 14471 Potsdam, GERMANY
tel. +49 (0)331 9513440, fax +49 1803 551863913 e-mail: info@zahnklammern.eu
Last update: 19.07.2011

Own prototypes of removable braces

This is not a commercial brochure for removable braces, but a collection of ideas and prototypes, which could be developped into budget jaw orthopedic solutions with low risk and high patient comfort.
Emphasis is here just on their principles. The prototypes are not professionally machined, are mostly not made on plaster models of „realistic“ cases and may comprise some wrong details.

Some of these appliances have only small plastic parts. These are better made by casting a viscous plastic mixture, than by mixing plastic powder and liquid on the model. Wax boundaries prevent this mixture from covering adjacent parts which should stay plastic-free.
The appliances are labelled with F für early treatment,  J  for treatment beginning in late mixed dentition and E for later and adult treatment.

1. AN F  J  Removable flexible lip bumpers
can stimulate frontal upper or lower jaw growth in children in case of crowing, without any danger of over-expansion and subsequent relapse. and can keep molars in place.
Carefully placed loops and bends allow to adjust the position of the bumper shield at the patient, and to re-adjust it later for further correction.
'This flexible suspension of the shield, and even more the use of soft silicone rubber there, enhances the activity of the lip muscles. By this, it accelerates the desired correction without applying any external force.

From top to bottom:
1. Conventionally made shield for lower jaw, containing 4 pre-fabricated triangular clasps. Two of these rest with their other end on the molars.
2. Shield for lower jaw with plastic surrounding the molars (here both 6 and 7). Reinforced by a frame of thin wire, this acts as clasps, with the advantage that the suspension of the shield can be anchored outside the molars and therefore does not need to cross the teeth. The shield itself is quickly made of plastic around the suspension and silicone rubber towards the lip pocket, auch schnell herzustellen. 2 additional interdental springs come from inside here.
3. similar, but the plastic clasps surround just the first molars, the shield is entirely of silicone and suspended deep in the lip pocket, to stimulate growth of the jawbone by the Fränkel effect.
4. Combined screw expander and lip shield (material like in 2.) for upper jaw with conventional triangular clasps.
All these appliances must leave the back of the jaw front free, to allow the tongue to enhance jaw growth, while screening the force of the lips which reduces jaw growth. Therefore, combination with an expansion screw is not possible for the lower jaw. Instead, the inner wire arch can be shaped as an expansion spring, as in the blue specimen under „lightweight spring expanders“. Shield 2. has also an expandable inner support, of which the back loops are not visible here.

2. AN F  J  E Lightweight (spring) expanders
do not hinder speech and are easy to adapt for patients of any age. Whereas the effect on adults is limited, larger expansions are possible in children with time. This removable appliance does it painlessly and economically. Any kinds of common clasps can be used. The strength of the spring can be made as required by choosing the thickness and the length of the bendings. The top right specimen is for the lower jaw.
The bottom right specimen contains a „memory-screw“, which has a spring included inside. Plastic which extends over the side teeth serves as clasps here. This could also be made by thermoforming of plastic sheet.
For derotating individual teeth, setup technique can be used here. Combination with silicone rubber (3.) is recommended when doing this in a greater extent.

If anchoring teeth are too conical or not yet fully erupted, so that the appliance fits only loosely, then tiny white attachments can be glued to these teeth, as are common in Invisalign® or similar therapies for certain cases. In contrast to bands or brackets, these neither hurt inside the cheeks, nor hamper to keep these teeth clean. The appliance will snap in firmly on them.

3. F  J  E Silicone rubber in removable orthodontics
Silicone rubber can be stuck to plate appliances by use of a primer. Such a plate can deliver a surrounding force to teeth which have been aligned on the plaster model before (setup / aligner technique). This rational technique would allow to correct tilted or twisted teeth already in mixed dentition, and would not require the manufacture of wire spring elements (but allow the use of screw elements, if advised). Derotations are also possible. If teeth lack a grip in the desired direction of force, white attachments can be added as a grip, see 2.
In t
he mainly orange specimen, silicone comprises 8 lower teeth, to re-align a beginning adult´s crowding, after slight stripping of these teeth. In the blue specimen, it comprises 6 upper teeth, also from both sides. This patient had a holistic treatment with prefabricated elastic trainers before, but a slight frontal crowding remained (perhaps no size of the trainers fitted perfectly). Moreover, his occlusion retained his left bicuspids in their visibly rotated positions. The silicone furnishing shown here is for the first of 2 or 3 derotation steps.

A further application of compounding silicone to plastic is to increase the efficiency of functional jaw orthopedic appliances, e.g. activators against deep bite.
To keep the silicone clean, it is recommended to brush it daily with baking soda.
Find detailed instructions with further examples (in German) from Fachlabor W. Paulus, Burgbernheim: www.positioner.de > Arbeiten mit Silikon

4.  J  E Recovery of lateral gaps: simply built distal plate appliances
Side teeth can migrate forward into gaps of milk teeth which were pulled too early, especially the lastmost milk molar 5 (usable in case of lacking permanent tooth). Sometimes they migrate also in adults after a tooth was lost. Even if the dentition changes normally, side teeth may push so much forward that they leave hardly any space for the important cuspids and are in poor occlusion.

A simple transversal expansion would not solve these problems and would be wrong here. Instead, the migrated teeth should be shifted back against the tide (distalized) to the places where they belong. At removable appliances, this requires good grips. Arrow clasps in series (see inset in pink) are well-proven, but difficult to make unless with special tools. Due to their deep-grip, they are recommended if the grasped teeth should still grow higher. But if not, then a good grip is easier to make by a simple wire frame with surrounding polymer around those teeth which are to be „screwed back“. This is shown here for a half-closed milk-5 gap (transparent-blue plate) and against crowding of the cuspids (red-yellow plate, should be modified when permanent 5s grow). The polymer tenon in the residual gap was simply cut through. It needs to be carved out gradually when the permanent tooth appears. Additional claspy elements in the frontal region are recommended, rather than a frontal bow. If both sides require distalization, a lip bumper (see 1. above) can be attached to the lower or also upper plate to relieve the frontal teeth from counter-force.
The all-blue plate (Thanks to www.kfo-soehngen.de ) served for pre-prosthetic treatment by means of purchasable 2-segmented sagittal screws on both sides. These avoid opening gaps which are unnecessary but sensitive. In both jaws, space could be shifted painlessly and rapidly from the end to the cuspid region, where it often lacks.

Important: to create space for crowded teeth, distalizing all side teeth should be second choice, since it just shifts the lack to the region of the wisdom teeth. Stimulating jaw growth during growth phase would be healthier. A little additional space can be created rather harmlessly by narrowing (stripping, slicing) the teeth, to an extent which depends on their shape.

5. F  J  4-element progenic plate appliance
Gentle, but straightforward treatment of progenic children has become rare, negating our tradition of removable appliances and functional jaw orthopedics (see in the case examples chapter for more about it).
Early treatment is essential in progenic cases, and a common (?) upper plate appliance can be equipped such that it would help, as in the 3 proven samples shown below. All 3 of them contain an expansion screw, 2 have two different types of a downward bow to hold the lower jaw back, and 2 have different protrusion springs or wires, which even allow to leave the frontal palate uncovered in the blue specimen, for higher comfort and for a healthy posture of the tongue. The pink-transparent sample, which seems to have been used in late mixed dentition, has little upper lip shields in addition, whereas large upper lip shields are recommended for Fränkel´s function regulator 3 (measure the depth of the patient´s lip pockets, replicate it on the plaster model and use a 2 mm thick wax spacer thereon, to leave 2 mm of free path for jaw development in forward direction).
The prototype of a frontally open bite back-shift plate which is shown here on the right combines all 4 of these active elements, to give a higher performance. For light / early cases, elements can be omitted according to the situation.
It bears a re-adjustable downward bow (taken from Tränkmann´s sample on the right below), large shields and a couple of single-ended protrusion arms, which should therefore have a diameter of at least 1,0 mm. The sturdy expansion screw was imitated from the blue specimen
, where it was intended to be unscrewed for up to 3 mm per month in cases of severely narrow jaw, up to a maximum of 10 – 12 mm, including overcorrection. For this purpose, the plate should be well equipped with strong clasps, worn 20/24 h and be screwed 1/8 turning per day. „Up to 3-fold faster expansion“ was also observed with special expansion screws which contain a spring inside. To profit from these here, all frontal double-ended elements (downward bow, shields) should be transformed into single-ended, to uncouple both halves of the plate for unhampered expansion.

6. F  J  E Lightweight retainers
With regard to their purpose, these retainers are durable and easy to clean. They are also hygienic in the mouth, because they leave most of the palatal surface free, so that its self-cleaning is only little hampered. The plastic extends there just 3 mm over the gums for the lower retainer and 5 mm for the upper retainer.
Small remaining refinements can be done by included springs (here for the lower front) or silicone rubber (see above). The shown specimens are just first examples for a possible variety.
The lower retainer has a „backbone“ of 1.1 – 1.2 mm wire, which touches the molars from both sides. The plastic comprises only the 5s to 3s in this specimen. To ensure a firm snap-in, it therefore bears additional ball clasps between the 5s and 6s. For the front, plastic can also be used

from one or both sides, as for the upper retainer here. The pair of connecting bars of this preliminary specimen is too thick, 0.9 mm wire instead of 1.1 mm would be sufficient, and the frontal bar should cross the palate 1 toothwidth more backward, for not interfering with the tongue.
This construction assures a tight fit by surrounding all teeth. A wire along the inside of the front could be added if needed. But mind the narrow vertical clearance behind the backmost teeth when letting a frame wire cross there. The more commonly built pair of light retainer plates shown on the left avoids this. It was provided after a treatment with aligner splints.