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The Cantilever Bite-Jumper System,
Exploring the Possibilities

by Joe Mayes, D.D.S.,M.S.D.

(Want to know more? Check out the interview with Dr. Mayes or Clinical Management of the CBJ by Paula Allen, both in Volume II, Issue 2 )

In this article, I will discuss various options and choices of adjunctive treatment that can be incorporated within the Cantilever Bite-Jumper System.

When the lower jaw of the typical Class II patient is slid forward to a super Class I position, the upper jaw is usually found to be too narrow and needs to be expanded. Also, the lower jaw may or may not need to be expanded. If the appliance has been purchased with Precision Lingual Hinge Caps already welded to the lingual of the upper and lower crowns, appliances can be fabricated to expand both upper and lower jaws. I usually have the Hinge Caps welded at the time of purchase, due to the frequent need for palatal expansion and for either expansion or use with a removable lingual bar for the lower jaw. This also allows us to expand with the Cantilever Bite-Jumper (CBJ) in place instead of having to delay its implementation until the completion of expansion.

We make our expanders in-house because we have an excellent lab. Fabrication of upper expanders is a very delicate operation. Each office can evaluate whether to do the lab work or to send it to a commercial lab. I have worked with AOA Lab on my designs and can recommend them to those not wishing to do the work in-house.

There are several ways to expand the upper arch, so choose the one you feel most comfortable with:

  1. Rapid palatal expander
  2. Quad helix
  3. Goshgarian arch (with or without extensions)
  4. Horseshoe or U-shaped arch
  5. W-arch

    6. I will describe the fabrication of each of these appliances.

    Due to tolerances in machining, the Precision Lingual Hinge Cap’s .032 x .032 slot will accept .032 x .032 Snug Fit stainless steel wire. Snug Fit wire allows less play than regular .032 x .032 wire but can be placed or removed easily, so I suggest that you make the appliances from Snug Fit stock and utilize regular .032 x .032 wire to hold the expansion. For instance, after the RPE is removed, a transpalatal bar could replace it to hold the expansion. (Figure 1)

    Fig 1. Transpalatal bar .032 X .032 or .032 round

    The RPE is fabricated after the stainless steel crowns have been fitted and the upper impression made and poured in quick-set lab plaster. The .032 x .032 Snug Fit arms are bent as shown in Figure 2. The vertical bend at the distal acts as a stop to prevent mesial movement of the arms in the slot. The bayonet bend on the mesial of the bracket prevents distal movement of the arm. The arm is bent to touch both teeth (D/4 and E/5) mesial to the molars. The arms are bent to conform to the tooth-palate junction. Gravity pulls the arms down so there is no play or loss of torque when expansion is started.
    The expander is adjusted to approximate these arms as closely as possible. Carefully solder the arms to the four legs of the expansion screw. Do not heat the Hinge Caps, as it will ruin them. Polish the appliance and cement it to place with the crowns and screws in the arches. At this stage the tubes are not attached but will be placed once the expansion is achieved. Bond a button or place bonding material to prevent the appliance from riding up. At the next visit remove the expander and place a transpalatal bar as well as the rods and tubes. Be sure to use Ceka Bond ® on the screw threads.

    Fig 2. RPE .032 X .032 Snug fit stainless steel

    A quad helix appliance is fabricated as any other but can be made of .032, .032 x .032 or .032 x .032 Snug Fit stock (Figure 3). Do not over activate any of these appliances, as they are made of stiffer wire than what is normally used. A Goshgarian-type wire may be used for expansion or rotation of the molars. We usually make this type appliance with .032 round TMA ® to allow more flexibility and to generate less force (Figure 4).

    Fig 3. Quad helix of .032 stainless steel

    Fig 4. Goshgarian .032 TMA round

    The horseshoe or U-shaped arch is made from .032 x .032 Snug Fit wire and is primarily used for molar expansion only, but it can expand the buccal segments if placed against them (Figure 5). The W-arch is probably the second most popular expander in my office and, once again, is made from .032 x .032 Snug Fit wire (Figure 6). Do not over activate this appliance either.

    Fig 5. Horseshoe or U, .032 snug fit stainless

    Fig 6. "W" .032 X .032 Stainless Snug Fit or TMA

    If any of these appliances are used on mixed dentition, a button or stop of bonding material should be placed occlusally on the lingual of the D/4. This prevents the appliance from "riding up" occlusally and losing its effectiveness. This procedure should also be followed on lower expansion appliances.

    The upper crowns may be purchased with buccal tubes attached for archwires. I recommend the Peerless ® tube which is small and comes with a ball hook. I routinely use brackets when I’m using the CBJ with a Class II, Division 2, or an adult case. Go ahead and move the lower jaw edge-to-edge, advance the four upper anteriors to a normal position and use shims to advance the mandible as needed. Adult cases will correct with mostly dental movement of the upper molars, and the distalization can be maintained with a Nance (Figure 7).

    Fig 7. Nance .032 X .032 Snug Fit stainless steel

    The appliances I use for lower expansion are the lingual bar, Frozat and labial expander. The lingual bar can be used to expand and upright the buccal segments (Figure 8). Since we use .032 x .032 Snug Fit wire, we can control the torque of the lower molars (Figure 9). Also, if you want to expand the 2nd molars and/or control their eruption, extend the distal wire from the distal bayonet bend and allow the wire to touch the lingual of the second molar and then form an occlusal rest.

    Fig 8. Lingual bar soldered - .045 stainless steel

    Fig 9. Removable lingual bar .032 X .032 Snug Fit

    The "Frozat" is a fixed Crozat framework. We make the appliance from .032 x .032 Snug Fit stock, and it can be mostly premade from the record model or as a second pour of the lower record model’s impression (Figure 10). Do not overactivate - the appliance can be removed and activated again, if needed. Once the desired expansion is achieved, a .032 x .032 Snug Fit lingual bar is placed to hold the expansion for the duration of the CBJ wear. This is my appliance of choice for expanding the lower.

    Fig 10. Frozat - .032 X .032 Snug Fit stainless

    A labial expander can be used if some lip bumper effect is desired (Figure 11). Small pieces of .045 lumen steel tubing (4.5 mm long) are soldered to the bottom of the cantilever arm. Two pieces of .045 stainless steel wire are bent as shown. Stops are soldered at the insertion into the .045 tubes. A longer piece of .045 tubing (8-10 mm) is soldered to one of the wires. Open coil Ni-Ti ® wire with a lumen of .045 is placed to expand against the tube and a stop. Lingual sweeparms of .032 x .032 Snug Fit are bent with bayonet bends to expand the teeth as the open coil moves the cantilever arms apart (Figure 12).

    Fig 11. .045 Stainless steel.

    Fig 12. Lingual sweep arms. 032 x .032 snug fit.

    Once the desired expansion has been achieved, there are three ways to maintain it. The tube of the labial wire may be crimped and locked down on the opposing .045 wire, or a new labial wire or lip bumper with stops can be used. However, I normally remove the complete labial appliance and replace the sweep arms with a .032 x .032 Snug Fit lingual bar.

    This appliance can be used for numerous other purposes. A short segment of .032 x .032 TMA can be used as a deimpactor for a second bicuspid or second molar (Figure 13). A molar uprighting spring may be used to upright the upper molar or to allow it to move bodily to the distal (Figure 14).

    Fig 13. De-impactor for 2nd bicuspids.

    Fabricated of .032 X .032 TMA. Always use labial stabilization.

    Fig 14. Uprighting springs. .017 X .025 TMA.

    Using .018 X .025 Peerless tubes.

    The uprighting spring is .017 x .025 TMA and requires the use of a Peerless ® tube on the upper molar. Your imagination is your only limitation.
    Additionally, the basic appliance lends itself to application similar to Dr. Terry Dischinger’s edgewise Herbst technique. Simply take a piece of .036 wire and bend as shown in Figure 15. Solder this rest to the occlusal of the cantilever arm and bond the lower anterior teeth with -10° torque OrthosTM brackets (now available from Ormco Figure 16).

    Fig 15. Occlusal rest bent.

    Lower anteriors bonded with -10 degree torque OrthosTM brackets. Note bonding of occlusal rest on lower 4's.

    Fig 16. Occlusal rest bent and soldered.

    The cantilever arm is manufactured with a .022 x .028 tube attached to the occlusal surface of the cantilever arm. Use .019 x .025 35° Copper Ni-Ti TM as a labial arch to unravel crowding of the lower anteriors and to stabilize the mandibular portion of the CBJ. Even if you don’t use this technique, the tubes may be useful. If any tipping of the cantilever arms occurs, lower braces may be placed to correct the downward and forward tipping.

    As all these appliances require impressions and pouring of models, a microetcher will be needed to help clean the inside of the previously microetched crowns. This is another reason to consider using an external lab for these appliances. However, the crowns should always be fitted in the mouth.

    To facilitate appliance removal, use Chap Stick ® on the occlusal of the molars before the appliance is cemented. This prevents the glass ionomer cement from sticking in the occlusal anatomy. Also, to reduce patient discomfort and movement, use topical anesthetic on the soft tissue where the bur will be used subgingivally.


    I hope the CBJ makes your Class II corrections easier. By being able to expand with the appliance in place, fewer appliances will be needed. This cuts down on costs and the number of treatment visits. One last thing, please remember not to try any of these more exotic procedures until you are past the learning curve and are totally comfortable with the basic appliance.

    A native of Crane, Texas, Dr. Joe H. Mayes received his B.S. from Texas Tech University, followed by his D.D.S., M.S.D. and Certificate in Orthodontics from Baylor College of Dentistry. Dr. Mayes is engaged in the private practice of orthodontics in Lubbock, Texas.

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