*Nitanium is a registered trademark and Palatal Expander2 and Molar Rotator2 are trademarks of Ortho Organizers, Inc., 1619 S. Rancho Santa Fe Road, San Marcos, CA 92069.

The NPE2 delivers a force of 350g in 3mm increments. If a 4mm expansion appliance is placed, the force will initially be higher, but will return to 350g once 3mm of expansion has occurred. Because the force application is preprogrammed, it is self-limiting. Neverthless, slight adjustments can be made by the clinician at any time to constrict the appliance or add further expansion.

Appliance Design and Selection

The NPE2 incorporates an innovative lingual attachment with .036" Ortholoy arms and molar loops for unilateral and bilateral adjustments (Fig. 2). A locking indentation in the lingual attachment fastens the appliance securely to the maxillary molar band. To prevent removal or accidental dislodging, the appliance should also be tied in with ligatures.

The vast majority of palatal expansion patients need at least 4mm of expansion at the maxillary first molars (2mm per side). An additional 2-3mm can be gained by adjusting the palatal Nitanium loop of the NPE2. If more than 8mm of expansion is needed, two separate expanders may need to be used in sequence. If the molars are too severely rotated to place an expander, a Nitanium Molar Rotator2 should be used prior to the NPE2.
 

The NPE2 is available in 10 sizes, from 26mm to 44mm in 2mm increments. The size of the expander is selected by one of the following two methods:

1. With the patient's mandibular first molars in normal position, measure the arch width between the tips of the right and left distobuccal cusps (Fig. 3). Now measure the arch width between the central pits of the maxillary right and left first molars (Fig. 4). The difference between these two measurements is the amount of expansion required. Measure the distance between the right and left maxillary first molars from the lingual surfaces where the sheaths will be placed (Fig. 5). Add this value to the required expansion. The total will indicate the size of NPE2 to use, allow­ing for the prescribed expansion plus 1.5-2mm of overcorrection to compensate for the combined width of the band material, cement, and lingual sheaths.

2. Measure across the mandibular arch between the central pits of the first molars (Fig. 6), then subtract 4mm to determine the size of NPE2 to use.

Appliance Preparation and Placement

1. After adequate separation, fit and place bands, with lingual sheaths attached, on the maxillary first molars.

2. Remove the bands, and assemble the NPE2 and the bands as one passive unit, securing the appliance to the bands with ligature wire (Fig. 7).

3. For patient education or for adjustment of the Ortholoy wire, the molar loops, or the Nitanium wire, a trial fitting can be done prior to cementation. Modifications of 1-2mm can be made to the Nitanium wire to increase or decrease the amount of expansion, and individual adjustments to the molar loops can be made as needed (Fig. 8).

4. For best results, use a triple-cure glass ionomer cement. Mix the cement, place the cement in the bands, and spray the entire surface of the Nitanium wire with a tetrafluoroethane refrigerant spray, which will make the appliance dead soft for easy placement (Fig. 9).
 

5. Seat one band completely, then seat the other band. Immediately cure the cement for 15 seconds per side initially, then for an additional 25 seconds per side to ensure a complete set (Fig. 10).

Fig. 9 Nitanium wire softened with refrigerant spray for placement.

Fig. 10 Light-curing of cement.

TABLE 1 USUAL LENGTH OF TREATMENT (MONTHS)

Expansion is normally completed in two to four months (Table 1). The appliance should then be left in place for two to three months of passive retention (Fig. 12).

Fig. 13 Case 1. 11-year-old female before treatment.

Fig. 14 Case 1. Palatal x-ray and NPE2 at initial placement.

Fig. 15 Case 1. After three months of expansion.

Fig. 16 Case 1. After three months of passive retention.

Case 2

A IO-year-old female presented with a Class I malocclusion with maxillary constriction, an open bite, and a fingersucking habit (Fig. 17).
        She needed 4mm of expansion and a size 34 NPE2 (Fig. 18). First-phase treatment objectives of expanded archform, space for cuspid eruption, and bite closure were achieved in four months (Fig. 19). The appliance was removed, and the case was allowed to settle with a Nance button retainer until full eruption, when detailing will be completed. The NPE2 could have been left passively in place to help intrude the molars and close the bite. X-rays showed an expanded palate with the suture intact and minimal tipping.

Fig. 17 Case 2. 10-year-old female before treatment.

Fig. 18 Case 2. Palatal x-ray and NPE2 at initial placement.

Fig. 19 Case 2. After four months of expansion.

Additional Functions of the NPE2

When the NPE2 is first placed, the Ortholoy arms will not contact the bicuspids (Fig. 20A). As. soon as the molars rotate, move distally l-3mm, and expand, the arms will touch the bicuspids (Fig. 20B). The appliance initially appears to move palatally, but as it expands, it will move occlusally. This will produce a lower tongue posture that can promote expansion and transverse growth in the mandibular arch (Fig. 21).
      The NPE2 also frees the growth restriction of posterior functional crossbite and provides space for impacted canines. At first, the movement will be orthodontic, but after expansion of the molars is achieved, there will be orthopedic changes in the maxilla and often mandibular repositioning as well.

Fig. 20 A. Ortholoy arms do not contact bicuspids at initial placement. B. After molar expansion, distal rotation, and distalization, Ortholoy arms contact bicuspids.

After expansion, the NPE2 can act as a stabilizing wire for molar intrusion (Fig. 22), or provide buccal root torque if the distal end (the wire inserted into the lingual sheath) is torqued with a plier (Fig. 23).

Other specialized uses:

. Unilateral molar correction (Fig. 24).

. Unilateral posterior crossbite correction (Fig. 25).

. Bilateral or unilateral contraction with smaller appliance sizes (Fig. 26).

. Distal rotation and expansion of both the first molars and second bicuspids (Fig. 27).

. Distal rotation and expansion of the molars and second bicuspids, followed by initial cuspid retraction
          (Fig. 28).

. Leveling, alignment, and rotation of the incisors while the buccal segments are expanded a fixed, three-way

          sagittal appliance (Fig. 29).

. Leveling, alignment, and rotation of the buccal segments while the molars are expanded and the incisors

  are retracted (Fig. 30).            

. Retention of expansion while the incisors are advanced (Fig. 31).

. Overexpansion of the palatal Nitanium loop in cleft palate cases (Fig. 32).

Fig. 24 Unilateral molar correction.

Fig. 25 Unilateral posterior crossbite correction.

Fig. 26 Bilateral or unilateral contraction with smaller appliance size.

 

Fig. 27 Distal rotation and expansion of first molars and second bicuspids.

Fig. 28 Distal rotation and expansion of first molars and second bicuspids, followed by initial cuspid retraction.

Conclusion

Advantages of the Nitanium Palatal Expander2 over traditional rapid palatal expanders include:

. Better physiologic response and stability.

. Preprogrammed to deliver the exact amount of expansion required and to stop at that point.

. No severe suture splitting.

. Less tipping of abutment teeth.

. Can influence the direction of maxillary and mandibular growth.

. Rotates molars buccally or distally.

. Can be used for anchorage.

. Shorter retention period.

. Placed at the chair, without laboratory procedures.

. Individually adjustable molar loops.

. Does not require frequent operator or patient adjustments.

. Built-in safety retention system.

. Less patient discomfort.

. Allows the patient to adjust the wire temperature to mitigate pressure.

. Less effect on speech and eating.

. Hygienic.

Fig. 31 Retention of expansion while incisors are advanced.

Fig. 32 Overexpansion of Nitanium loop in cleft palate case.