A two-wire SmartArch protocol to shorten the leveling and aligning phase

By Jeff Kozlowski, DDS

Charles Burstone, DDS, MS, laid the foundation for multi-force wires in 1981 with his pioneering article in the American Journal of Orthodontics and Dentofacial Orthopedics.1 “Various-Modulus Orthodontics” was a vision for a future in which each tooth could be optimally engaged with abiologically relevant forces. Although conventional wire technology has developed gentler and more continuous forces over time, forces are far from relevant to any particular dentition.  

The number of multi-force archwires on the market has proliferated in recent years; nearly every major orthodontic distributor now offers them. They are nearly identical in design, featuring three stiffness regions.7  Differentiation is scarce. However, a new generation of multi-force archwires has been developed: SmartArch wires (Ormco Corp).  

smartarch
Figure 1: SMARTARCH is programmed with a biomechanically optimized stiffness profile. Each interbracket region has an ideal stiffness, shown here by a different wireframe color overlay, to deliver the biologically correct forces to the targeted tooth.

SmartArch wires are programmed with distinct stiffness in each inter-bracket region (Figure 1) targeting each tooth with a prescribed force, calculated to deliver the same low, constant stress to each PDL in the arch. This is the key differentiator for SmartArch technology; all PDLs are viewed individually to experience the optimum stress window regardless of position.2,3,4,5,6 

In this case study, I will review conventional standards of treatment efficiency and patient expectations with this emerging archwire technology. In my practice, we are able to eliminate multiple appointments and 3 to 4 months of initial stage (leveling and aligning) treatment time with these archwires. This results in significant reduction in average case length. I will also review other clinical studies from Sarver, Roberts, Olsen et al, who achieved 50% greater tooth movement with this technology in early treatment phases, resulting in 20% to 30% overall efficiency gains across multiple bracket systems. My clinical experience invites readers to achieve new standards of care when technology meets biology.   

Case Examples

In prior case studies8,9,10,11 among other colleagues, SmartArch has demonstrated highly efficient malocclusion resolution, with concurrent arch development. Full engagement to the posterior is recommended (6’s and 7’s) from treatment day one. In these cases, the round SmartArch was placed at the beginning of treatment and left in place for 8 to 12 weeks; significant anterior alignment and posterior leveling and aligning were observed. Curve of Spee is also resolved sooner than traditional archwires. Rectangular SmartArch demonstrated more efficient torsional resolution than current archwires because of targeted forces per tooth in the 3rd order.

A recent case study from Sarver and Roberts concluded8:

  • The 0.016″ SmartArch demonstrated 25% faster treatment than control CuNiTi’s with >56% more correction, mostly due to significant deep bite and Curve of Spee resolution that typical starting wires cannot achieve.
  • In a 6 month study, SmartArch series (round and rectangular) were found to be more efficient than a typical 4 to 6 wire progression in correcting malocclusions with a >3mm deep bite (75% of cases). The SmartArch series cases corrected to near ideal alignment (<29 cast discrepancy score), taking cases far closer to the finish line in less time.  
  • SmartArch demonstrated 50% greater tooth movement than standard CuNiTi controls.

A more wide-ranging study from Roberts et al demonstrated9: 

  • Bonding to fully erupted second molars with SmartArch has a significant positive effect on efficacy and minimizing treatment time.  
  • SmartArch 0.016″ round demonstrated +20% teeth correction in 20% less time versus standard CuNiTi sequence in 0.018″ slot Ti Orthos brackets.
  • SmartArch 0.016″ round demonstrated +33% teeth correction in 29% less time in Damon Q brackets versus standard CuNiTi sequence in Ti Orthos.
  • SmartArch 0.016″ round demonstrated +12% teeth correction in 10% less time in Damon Q brackets versus Ti Orthos. 
  • SmartArch 0.016″ round demonstrated optimum clinical performance in the first 90 days of treatment.
  • SmartArch significantly reduced deep bite and Curve of Spee, standard CuNiTi did not. SmartArch was thus demonstrably better at leveling arches.
  • Using Cast Alignment Evaluation (CAE), a 10-patient study found 30% of cases in the SmartArch series (round and rectangular) achieved a “board quality result” (<26 points) in 6 months. The mean value for the study came very close (28.7 points).
  • The SmartArch 2-step 3D alignment series demonstrated significant treatment time savings and compatibility with multiple bracket systems.

In the Journal of Clinical Orthodontics, Olsen concluded11:  

  • “In each case shown here, SmartArch treatment appeared to minimize the lag phase, making coordinated tooth movement more efficient and leading to an estimated 50% savings in leveling and alignment time.”

Testing SmartArch

Alongside the clinical evaluations performed by Sarver et al, which aimed at reducing the number of wires required for the leveling and aligning phase, we decided to test the ability for SmartArch to concurrently reduce the total time required of the leveling and aligning phase. The basic premise of the evaluation was this: If the two wire SmartArch sequence could effectively replace the 3-4 wire sequence employed in traditional Damon System protocols, would there be a resulting time savings in treatment for the patient and practitioner? Historically the Damon System wire sequence consisted of three wires, 0.014″ CuNiTi, 0.014″ x 0.025″ CuNiTi, and 0.018″ x 0.025″ CuNiTi, typically placed at 10-week intervals. Occasionally an intermediate 0.018″ CuNiTi wire would be placed after the 0.014″ if leveling and aligning were not sufficient to proceed to the 0.014″ x 0.025″ at 10 weeks. With the standard Damon System 3-4 wire sequence, the typical time for leveling and aligning phase was approximately 30 to 40 weeks. Our goal with the new two-wire SmartArch protocol was to see if we could shorten the leveling and aligning phase to approximately 20 weeks, which would result in a treatment time savings of 12 to 16 weeks.

  • Figure 2
  • Figure 3

Figure 2: Initial bonding: Upper arch; same day start. Class II, Division 2, narrow buccal corridors, moderate crowding. A .016″ SmartArch wire placed 7-7 and cinched distal to upper 7s. Figure 3: Initial bonding: Lower arch; same day start. A 016″ SmartArch wire placed lower 7-7 and cinched distal to 7’s. Turbos placed lower 6’s for disarticulation. Started shorty Class II elastics from lower 6’s to upper 4’s. Notice the discrepancy between the lower 6’s and 7’s. The .016″ SmartArch wire was designed to be placed 7-7. In the traditional Damon System protocol, the initial lower .014″ wire would have been clipped at the lower 6’s requiring a transitional .018″ wire to align these teeth prior to proceeding to the .014″ x .025″ CuNiTi.

The initial protocol for our SmartArch evaluation was to place upper and lower 0.016″ SmartArch at initial bonding and then proceed to upper and lower 0.018″ x 0.025″ SmartArch at the subsequent visit (Figures 2 and 3). Rather than having a standard appointment interval of 10 weeks for each wire, we decided to customize the appointment interval between visits based on the time we expected it to take for sufficient leveling and aligning to occur to proceed to the 0.018″ x 0.025″ SmartArch. For cases that were less crowded or had minor rotations, this interval may be planned as short as 6 to 8 weeks. While for more significant crowding and/or rotations, the interval may be as long as 10 to 12 weeks (Figures 4 and 5).

  • Upper 10 weeks SmartArch
    Figure 4
  • Figure 5

Figure 4: 10 weeks. Upper arch; a .018″ x .025″ SmartArch wire placed. Notice the leveling and aligning from the .016″ SmartArch and the relative ease of placement of the .018″ x .025″ SmartArch as only minor rotations and crowding remain. Figure 5: 10 weeks. Lower arch; a .018″ x .025″ SmartArch wire placed. Minor space developed in the anterior due to the arch development with minimal initial crowding therefore chain elastic was placed 6-6. Notice the beautiful alignment of the lower 6’s and 7’s allowing easy and comfortable placement of the .018″ x .025″ SmartArch.

Many practitioners follow the leveling and aligning phase with a repositioning appointment prior to progressing to the working or finishing wires. In our office our primary working/finishing wires are upper 0.019″ x 0.025″ stainless steel (SS) and lower 0.016″ x 0.025″ SS. In cases that are Class I and do not need AP mechanics, we schedule the repositioning appointment 8 to 10 weeks after the 0.018″ x 0.025″ SmartArch is placed (Figures 6 and 7). In cases that are Class II or Class III, we will proceed to the upper 0.019″ x 0.025″ SS and lower 0.016″ x 0.025″ SS and use mechanics (usually elastics) to address the AP correction. For the cases that require AP correction, we plan our repositioning visit once the patient is Class I as we believe this allows for more effective repositioning of brackets to account for the detailed occlusion we aim to achieve.

  • Figure 6
  • Figure 7

Figure 6: 20 weeks. Upper arch; a .019″ x .025″ SS placed. Upper 3-3 to consolidate and avoid anterior spacing with further arch development. Figure 7: 20 weeks. Lower arch; a .016″ x .025″ SS placed. Lower 3-3 to maintain anterior space closure during arch development. Note on case progress: As this patient is Class II, we proceed to the “working” wires of upper .019″ x .025″ SS and lower .016″ x .025″ and run Moose 5/16″ 6 oz Class II elastics from lower 6’s to posts placed between the upper 23’s. Turbos remain in place for disarticulation during Class II mechanics. We will perform our iCAT and repositioning appointment once the patient is Class I. It is clear that the LL5 needs to be repositioned for mesial root tip and we will address this at the repositioning appointment.

The two primary questions we had in the design of this new two-wire SmartArch protocol were:

  1. What percentage of patients could we effectively level and align with two wires?
  2. Would we be able to regularly progress to the upper 0.019″ x 0.025″ SS and lower 0.016″ x 0.025″ SS after only 20 weeks of SmartArch leveling and aligning?

During the evaluation we found that approximately two-thirds of our patients had effective leveling and aligning with the 20-week, two-wire sequence, and most of these patients progressed directly into the stainless steel working/finishing wires. Most of our patients require AP correction and therefore progress immediately from the 0.018″ x 0.025″ SmartArch into the upper 0.019″ x 0.025″ SS and lower 0.016″ x 0.025″ SS. Considering that this transition occurs at approximately 20 weeks into treatment, we believe this shows both the effective leveling and aligning of the two-wire SmartArch sequence and a resulting 3 to 4 month time savings in treatment. Along with the reduction in treatment time we are experiencing, there is a concurrent savings of one to two patient visits to the office. Our current goal for comprehensive treatment is to complete treatment in 13 visits or less on average across all patients. We believe that the new two-wire SmartArch protocol will enable us to decrease our total visits to complete treatment to 11 to 12 visits on average.

More recently we have modified the two-wire SmartArch from our initial protocols. Because our lower working/finishing wire is usually a 0.016″ x 0.025″ SS, we didn’t require the additional thickness of the 0.018″ x 0.025″ SmartArch to progress to this wire. Therefore, we are currently using a lower 0.016″ x 0.025″ CuNiTi as our second leveling wire. Given the lower arch has a smaller inter-bracket distance and no need for the larger 0.018″ x 0.025″ SmartArch to make the transition, the 0.016″ x 0.025″ CuNiTi allows more patients to effectively level and align in two wires. This change has helped us increase the number of patients we can treat with a two-wire sequence to approximately 75%. We are currently looking to develop a lower 0.016″ x 0.025″ SmartArch as we believe this wire will further increase the percentage of patients that can benefit from effective leveling and aligning with a two-wire sequence.

Conclusion

Our experience with the SmartArch supports prior clinical observations by other colleagues. This technology enables our practice to reconsider treatment planning and case duration for a majority of our fixed appliance patients. In my busy practice, there are significant clinical and business advantages to eliminating multiple wires, one to two  appointments and 3 to 4 months from routine cases. With our new SmartArch protocols, we believe that we can achieve effective leveling and aligning for more than 75% of all cases. The savings of both appointments and treatment time makes for a happy clinician and happier patients. OP

Jeff Kozlowski, DDS, is an internationally sought-after lecturer who has presented numerous times at the American Association of Orthodontists, at dozens of state orthodontic societies, and in numerous countries around the world. He graduated with a BS in economics from Syracuse University prior to receiving his DDS and orthodontic specialty certificate from the State University of New York at Buffalo. He has been practicing orthodontics for more than 20 years and owns thriving practices in New London, East Lyme, and Mystic, Conn. Kozlowski is a paid consultant for Ormco.

References

  1. “Variable-Modulus Orthodontics” AJODO Vol 80 Issue 1, Burstone, 1981.
  2. “Biology of Biomechanics: Finite Element Analysis of a Statistically Determinate System..” AJODO Vol 148 Issue 6 Centennial Special Article, Roberts, Viecilli, Chang et al. 2015
  3. “Three Dimensional Mechanical Environment of Orthodontic Tooth Movement and Root Resorption” AJODO Vol 133 Issue 6, Viecilli, Roberts, Katona et al. 2008
  4. “Orthodontic Mechanotransduction and the Role of P2X7 Receptor” AJODO Vol 135 Issue 6, Viecilli, Roberts, Chen et al. 2009
  5. “Ideal Orthodontic Alignment Load Relationship Based on PDL” Orthodontics and Craniofacial Research Vol 18, Viecilli, Burstone 2015
  6. “Effects of Initial Stresses and Time on Orthodontic EARR” Journal of Dental Research 92:346, Viecilli et al. 2013
  7. “Review of Superelastic Differential Force Archwires” Current Osteoporosis Reports: Craniofacial Skeleton Issue, Kuntz, Khan et al. 2018
  8. “Super Elastic Archwire Can Achieve Efficient Movement and Reduced Trauma,” Orthodontic Practice US Vol 10 Num 6, Sarver, DM, Roberts WE December 2019
  9. “SmartArch Multiforce, Super Elastic Archwires:  A New Paradigm in Orthodontics”,Journal of Digital Orthodontics Issue 55 Roberts WE, Sarver DM, Tracey S, Roberts J July 2019
  10. “No Tooth Left Behind, A Compelling Case for Orthodontic Archwire Technology” Orthodontic Products  Cosse, Chris June 2019
  11. “SmartArch Multiforce Super Elastic Archwire : A New Paradigm in Orthodontic Treatment Efficiency” Journal of Clinical Orthodontics Volume LIV Number 2  Olsen, Marc February 2020