IntroductionPractitioners using passive self-ligating brackets have reported many advantages in areas such as shorter treatment duration,1,2,3 quicker dental arch changes,3,4,5 more efficient space closure6, handling efficiency1,2,7,8 and a higher level of comfort.5 But now that treatment deficiencies of certain passive self-ligating brackets are being more thoroughly investigated,9,10 many orthodontists are becoming more aware and are even somewhat disenchanted with the apparent inefficiency of some brackets in finishing cases.

I have personally experienced finishing difficulties with the Damon System, and despite over seven years of teaching and recommending this system, I longed for a better way to treat and finish my cases with fewer bends. Reaching outside the Damon circle of influence, I learned that the initial wave of popularity of the Damon System (Ormco, Glendora, CA) had already yielded to improvements found in newer, more effective designs, like the third generation SmartClip™ SL3 Self-Ligating Bracket and its aesthetic counterpart, the Clarity™ SL Self-Ligating Bracket. This article highlights my clinical observations in my transition from the Damon System to the more efficient SmartClip™ SL3 Self-Ligating Appliance System.

BackgroundSelf-ligation and, more specifically, “passive” self-ligating bracket systems have been embraced by many practitioners like me because of the many clinical advantages seen in the efficient movement of teeth with light, comfortable forces. The early pioneers who were the first to leave traditional “ligated” systems started a manufacturing “Self-Ligation Evolution” aimed at creating the perfect appliance. The difficulties encountered with these first attempts probably slowed their acceptance but also provided the foundation for the eventual improvement of these systems. I have a tremendous respect for the individuals who invested in the revival of passive self-ligation concepts and treatment systems, because they openly welcomed a new generation of orthodontists to join them in advancing the art of self-ligation.

When I began teaching the Damon System for Ormco in 2005, I was tasked to create the first “In-Office” course sanctioned by inventor Dr. Dwight Damon; so, I became invested in the purest form of his technique. This undertaking became the foundation of my first experience in passive self-ligation and influenced my thinking, ultimately changing my treatment philosophy. Soon after, my education company, intelliDENT solutions, Inc., offered an online curriculum and even an educational continuum called the “Damon Journey” which further solidified my understanding of this system. I was also empowered with teaching it to the orthodontic residents at Georgia Health Sciences University. After teaching regularly at the annual user meetings and in Advanced Courses, and with some ideas of my own, the foundation was set for my transition to the next level in the advancement of self-ligation – SmartClip SL3 and Clarity SL Self-Ligating Brackets.

Dr. Robert

Waugh practices

orthodontics

full-time in Athens,

Georgia. He

graduated from

Georgia Health Sciences University

(formerly the Medical College of Georgia)

in 1987 with both a DMD and an MS in

Oral Biology, and was elected to OKU –

dentistry’s honor society. Dr. Waugh

earned his Masters in Orthodontics at Baylor

University in 1989 and became certified

by the American Board of Orthodontics in

2000. Dr. Waugh is an Assistant Professor

of Orthodontics at Georgia Health Sciences

University, a nationally-known lecturer on

current orthodontic topics, and a seminar

speaker for 3M Unitek.

Top Ten Finishing Advantages of SmartClip™ SL3 Self-Ligating Brackets A Comparative Analysis of Damon® Q and SmartClip™ SL3 Self-Ligating Bracketsby Dr. Robert Waugh

Leaving one passive system for another, I entered this transition with a considerable bias for the Damon System. I deliberately did not adjust my treatment planning regarding its ability to treat severe crowding in a non-extraction manner so I could fairly evaluate the SmartClip™ SL3 Self-Ligating Bracket’s performance. My comparative findings follow, along with a chart of my personal comparative analysis at the conclusion of the article (Table 2).

Finishing Advantage #1: Bracket PositioningNothing tops “bracket positioning” when it comes to reaching an excellent and timely orthodontic finish. Medium size brackets, like SmartClip SL3 and Clarity™ SL brackets, with exposed slots and rhomboidal design are easier to see and position on teeth than mini-brackets. With better consistency in positioning, orthodontists gain a huge advantage in finishing efficiency. Using the metal “clips” as a visual cue is helpful in directing the tooth-colored Clarity SL bracket along a tooth’s long axis. The same is not true for the metal-free Damon® Clear™ bracket. Additionally, most orthodontists don’t realize the sides of a ceramic Damon Clear bracket are not parallel and cannot be used as a visual cue for the long axis (Figure 1A-B).

In the comparative analysis, the SmartClip SL3 bracket has tighter labio-lingual limits (.0275") than Damon (.028"). Although this difference (.005") seems insignificant, it turns out to be huge in terms of fewer bends and better finishing efficiency. Now, combine these bracket depth tolerances with the ease of selective ligation and the SmartClip bracket becomes the better finisher.

Finishing Advantage #3: Variable Bracket WidthDamon Q brackets are designed with the same widths for all teeth (exception lower incisors). A variety of bracket widths for a variety of tooth widths are provided by 3M Unitek in the SmartClip SL3 and Clarity SL bracket series’ to give a distinct element of control to the orthodontist. For example, the upper central incisor in the SmartClip SL3 bracket is .130", compared to the narrower Damon bracket at .110" (Table 1). Consequently, the SmartClip SL3 bracket offers better control due to extended rotational and tip holding points for larger teeth.

Figure 1A-B: SmartClip™ SL3 and Clarity™ SL Self-Ligating Brackets feature parallel mesial and distal sides that aid in bracket positioning.

1A 1B

This design difference can be confusing for practitioners whose eyes are conditioned to the metal bracket’s parallel sides. Although, more miniature Damon brackets are provided with placement jigs, I always found the jigs cumbersome, interfering with the gingiva and often distorted from the packaging process. Now that I can actually see what I’m positioning with SmartClip and Clarity SL brackets, I seem to be a better bracket placer. Imagine that!

Finishing Advantage #2: Slot DepthSlot depth determines the degree of labio-lingual play between a self-ligating bracket and the wire. Many experienced Damon doctors know that when placing an up or down bend, they must also place an in or out bend. This exaggerated labio-lingual play complicates treatment, requiring compensating bends to avoid inadvertently throwing the wire to the front or back of the slot. In finishing and detailing, fewer bends translates into fewer visits to line up the contact points of teeth and establish both aesthetics and a functional occlusion. I have found that these first-order compensating bends are not necessary with SmartClip brackets.

Table 1: A comparison of mesial-distal widths of selected Upper Central Brackets.

Upper Central Brackets M-D Width

Damon® Q .110" 2.8 mm

In-Ovation® R .116" 2.9 mm

SmartClip™ SL3 .130" 3.3 mm

More specifically, there is a total of only 2° of rotational play with a SmartClip bracket on a .019×.025 finishing wire on a central incisor (Figure 2A), compared to 8° of play with the Damon bracket (Figure 2B). This difference results in better efficiencies in achieving complete rotational and tip correction and in space closure.

Figure 2A: SmartClip™ SL3 Self-Ligating Bracket – Tight rotational control with only 1° loss per side (2° total) with a .019×.025 archwire.

Figure 2B: Damon Self-Ligating Bracket – Difficulty with rotation control due to more than 4° loss per side (8° total) with a .019×.025 archwire.

Finishing Advantage #4: Tie-WingsAddressing the specific needs of patients from visit to visit can be difficult without the basic physical requirements of bracket design available. SmartClip SL3 and Clarity SL brackets are designed with deep tie-wing undercuts which allow single or multiple attachments to be added at will (Figure 3A-D). Stainless steel ligatures, elastic chain, elastic ligatures, and coil springs may all be employed in a

2A 2B

cleansable delivering finishing advantages to SmartClip bracket users over Damon bracket users. Plus, a cooperative patient with fixed hooks has fewer emergencies over bent or missing drop-in hooks.

Finishing Advantage #6: Pre-Coated BracketsHaving assurance that the adhesive is uniformly pre-applied to SmartClip brackets is a measurable advantage in bonding. Applying glue from a syringe system to a Damon bracket pad without remembering to “butter it” into the mesh can introduce qualitative and quantitative errors that could affect bond strength and bracket position. Most orthodontists generally agree that adding unnecessary procedures can introduce new variables that upset the bonding process. Moreover, the possibility of contamination increases with each new step. 3M Unitek’s bracket pre-coating (APC™ Adhesive Coated Appliance System) combines the best adhesive with the best bracket for direct and indirect bonding. Since I was already using 3M adhesives on my Damon brackets when I made my transition, it was a comfortable move for me to trust the performance of the pre-coated brackets from 3M. Now I have the best of both worlds!

Finishing Advantage #7: Ceramic Bracket RemovalFor a busy practice, the removal of ceramic brackets can be predictable or unpredictable. The Damon removal tool places an occlusogingival shearing force on the bonds, torqueing the teeth and adding undue strain on the enamel. These forces can leave the bracket bases intact while fracturing the weaker door mechanisms, forcing the practitioner into a difficult clean-up (Figure 5A). Alternately, the Clarity SL bracket is pre-scored to collapse in a mesio-distal direction without stress for the patient or practitioner, ending in a comfortable and predictable procedure (Figure 5B).

Figure 3A-D: Side profile comparisons of 3M™ Self-Ligating Brackets (L) and Damon® Self-Ligating Brackets (R). The deeper under tie-wing area of 3M Self-Ligating Brackets allows for easier ligation.

5A 5B

Figure 5A-B: A Damon® Clear™ Bracket after fracturing (L) and Clarity™ SL bracket (R).

variety of binding and non-binding configurations to complement treatment. Damon® Q brackets have reduced undercut areas that make it difficult to tie or chain, especially in its clear version. Without the flexibility to handle multiple ties and attachments, an efficient finish is compromised. The ease of being able to seat the wire into the base of the slot with SmartClip bracket tie-wings is the key to labio-lingual positioning and efficient finishing.

Finishing Advantage #5: Fixed HooksThe advent of a drop-in hook was an attractive option regarding hygiene, but in practical use they are too weak for elastic forces. Consequently, extended treatment due to compromised elastic wear even more adversely impacts hygiene. Simple attention to hygiene and returning to fixed hooks on upper and lower canines and first bicuspids in the SmartClip SL3 brackets have been a welcomed change (Figure 4A). Damon Q uses a convenient vertical slot for a drop-in hook, only it is located on the lingual side of the slot, which makes it difficult to place and access (Figure 4B). Fixed hooks on the labial side of the slots are more accessible, durable, and

Figure 4A-B: Images of hooks for the SmartClip™ SL3 Bracket and Damon® Self-Ligating Bracket.

4A 4B

3A 3B

3C 3D

Reprinted from Orthodontic Perspectives Vol. XIX No. 2. © 2012, 3M. All rights reserved.

Finishing Advantage #8: Selective LigationOnce the alignment of teeth is achieved, it is generally time to selectively ligate the wire to the base of the slot for control and finish. Damon practitioners later lose this alignment to the side effects of elastics forces. In SmartClip™ SL3 and Clarity™ SL Self-Ligating brackets, low-force, low-friction mechanics are used early without ligatures, and when it comes time to reduce the play between the wire and slot, they can easily be bound with elastomeric ligatures. Once bound to the base of the slot, play is removed and elastic forces may be distributed to the arch without individual teeth yielding. The efficiency of selective binding is available to SmartClip bracket users through the selective use of its clips and tie-wings. Ask yourself what your most common bend in your Damon practice is, and why? I suggest to you that it might be due to the inability to selectively bind.

Finishing Advantage #9: Space ClosureFudging bracket positions for me is a thing of the past now that I have moved to SmartClip brackets. Before SmartClip brackets, I found the trick to space closure in Damon was to exaggerate your bracket placement in the direction of the space to be closed. For example, a central diastema closure requires an exaggerated position in order to converge the roots appropriately due to excessive play between central incisors (Figure 6). This “see-saw” tipping play is also seen in extraction site closure and generally seen in closure of large amounts of space. With SmartClip brackets, I am now routinely positioning the brackets accurately for the individual teeth and having great success closing spaces predictably and efficiently.

6

Figure 6: Tip bends placed to counteract the lack of tipping control with Damon® brackets for diastema closure.

Finishing Advantage #10: Synergy of Additive AdvantagesWhen the list of Finishing Advantages is combined, there is a synergistic effect that takes place in patient care. The list is summarized in Table 2 and serves as an exclamation point on my experience with the SmartClip SL3 and Clarity SL bracket systems.

Table 2

Bracket Characteristics Damon® Q Damon®

Clear™SmartClip™ SL3 Clarity™ SL

Slot Depth .028" .028" .0275" .0275"

Debonding Acceptable Difficult! Acceptable Superior

Rotation Control Difficult! Difficult! Superior Superior

Tie-Wings Limited Limited Superior Superior

Tip Control Difficult! Difficult! Superior Superior

Bracket Width Narrow Narrow Wide Wide

Cues for Visual Positioning Rhomboid Trapezoidal Rhomboid Rhomboid

Early Alignment Comparable Comparable Comparable Comparable

Finishing Control Difficult! Difficult! Superior Superior

Selective Binding Difficult! Difficult! Superior Superior

ConclusionIn my experience, the design considerations employed by 3M Unitek for both SmartClip SL3 and Clarity SL Brackets provide all of the advantages of passive self-ligation with the added benefits of predictable finishing. I welcome your comments and opinions regarding my experiences and look forward to sharing more in the near future on related archwire principles and the application of lateral development mechanics.

References1 Eberting JJ, Straja SR, Tuncay OC. Treatment time, outcome, and patient

satisfaction comparisons of Damon and conventional brackets. Clin Orthod Res 2001; 4: 228-234.

2 Harradine NW. Self-ligating brackets and treatment efficiency. Clin Orthod Res 2001; 4: 220-227.

3 Pandis N, Polychronopoulou A, Eliades T. Self-ligating vs conventional brackets in the treatment of mandibular crowding: a prospective clinical trial of treatment duration and dental effects. Am J Orthod Dentofac Orthop 2007; 132: 208-215.

4 Franchi L, Baccetti T, Camporesi M, Lupoli M. Maxillary arch changes during leveling and aligning with fixed appliances and low-friction ligatures. Am J Orthod Dentofac Orthop 2006; 130: 88-91.

5 Scott P, T DiBiase A, Sherriff M, Cobourne M. Alignment efficiency of Damon3 self-ligating and conventional orthodontic bracket systems: a randomized clinical trial. Am J Orthod Dentofac Orthop 2008; 134: 470. e1-8.

6 Deguchi T, Imai M, Sugawara Y, Ando R, Kushima K, Takano-Yamamoto T. Clinical evaluation of a low-friction attachment device during canine retraction. Angle Orthod 2007; 77: 968-972.

7 Shivapuja PK, Berger J. A Comparative studyof conventional ligation and self-ligation bracket systems. Am J Orthod Dentofac Orthop 1994; 106: 473-480.

8 Berger JL, Byloff FK. The clinical efficiency of self-ligated brackets. J Clin Orthod 2001; 35: 304-308.

9 Turnbull NR, Birnie DJ. Treatment efficiency of conventional vs self-ligating brackets: effects of archwire size and material. Am J Orthod Dentofac Orthop 2007; 131: 395-399.

10 Miles PG, Weyant RJ, Rustveld L. A clinical trial of Damon 2 versus conventional twin brackets during initial alignment. Angle Orthod 2006; 6: 480-485.

11 Badawi H, Toogood RW, Carey JPR, Heo G, Major PW. Torque delivery of self-ligating brackets. Am J Orthod Dentofac Orthop 2008; 133: 721-728.

Case photos provided by Dr. Robert Waugh.