Virtual Treatment Planning

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2 feature \\ case presentation Virtual Treatment Planning Reduce Frustration with The Right Sequence Jamie Reynolds, DDS, MS Virtual treatment planning that directs the fabrication of customized orthodontic appliances has been the focus of pioneers in the profession for a number of years now. One such innovator was Dr. Craig Andreiko, the inventor of bondable mesh, among many other orthodontic advancements. He told me once that the difference between customized digital orthodontics and traditional orthodontics is that with digital orthodontics, we get to put braces on straight teeth. It seems like a simple concept, but actually it is quite profound. Customarily, we place braces on crooked teeth, level and align the arches, then react to errors in bracket position and variance in dental anatomy. Dr. Andreiko s concept of digital orthodontics was to move ever closer to the ultimate straight-wire appliance that Dr. Larry Andrews first envisioned nearly 50 years ago. Regardless of the software employed, unless you have guidance, treatment planning your first digital case can be intimidating. I had no idea where to start planning my first cases. Now having treatment planned more than 1,000 cases using Insignia, the system of virtual treatment planning and customized appliances that Andreiko developed, I have established an Approver interface sequence (outlined here). When combined with appropriate mechanics and treatment planning, this sequence helps me achieve consistently accurate setups and reliable clinical finishes (Fig. 1). Fig Establish the Vertical Position of the Upper Central Incisor 2. Address the Buccal Corridors 3. Ensure Proper Upper Central Incisor Inclination 4. Protect or Reshape the Smile Arc 5. Determine Lower Posterior Torques 6. Verify Anterior Torques 7. Validate the Occlusion Dr. Jamie Reynolds s Insignia Advanced Smile Design Approver Sequence As with all digital models, the quality and consistency of the digital setup is of critical importance to the clinical outcome and the efficiency with which the case is treated. Using this sequence should provide the novice and even experienced users of this platform with improved clinical finishes and more predictable results. Fig. 2 Steps 1-2: Comparing the setup (right) with the patient s smiling extraoral photograph offers a general sense of the overall setup, helps establish the vertical aspect of the upper central incisors and assess the planned transverse development. Steps 1 and 2: Establish the vertical position of the upper central incisor, and address the buccal corridors Every setup needs to start somewhere. In my residency, I was trained to begin planning with the angulation of the lower central incisor; however, starting virtual treatment planning with the position of the upper central incisor position helps to achieve improved aesthetic results, while also allowing me to plan excellent functional outcomes. The first step, then, is to evaluate the smiling position of the upper central incisor side by side with the digital setup (Fig. 2). This allows me to ensure the bracket positions and planned mechanics do not lead to an unesthetic position of the upper incisor. Toggling between T1 (initial position) and T2 (final position) allows me to get a feel for the patient s smile and see if the upper incisors move as desired. The entire plan is built around the vertical positions of the upper central incisors. For this case, the vertical aspect of the upper centrals in the setup is spot-on. The same images and T1/T2 toggle are used to address the buccal corridors. Playing the embedded video between T1 and T2 also helps ensure that the vertical positions of the upper central incisors and the planned transverse development are appropriate. For this patient, I felt it was necessary to widen the buccal corridor for the best esthetics. orthotown.com \\ OCTOBER

3 case presentation // feature Step 3: Ensure proper upper central incisor inclination The most esthetic position for the upper central incisor where light reflection upon smiling is at its best is for its facial surface to be set on a tangent, 90 degrees to Frankfort horizontal. 1 Expert tip: When setting up the case, use the control key to rotate the digital occlusal plane to match the patient s natural occlusal plane. Orientating the proper occlusal plane will allow the right side of the screen to simulate Frankfort perpendicular and ensure the torque of the upper central incisors in the setup are where desired (Figs. 3a and 3b). For this case, the upper incisors required significant facial crown torque to achieve the ideal angulations. The software-calculated, patient-specific torque values are essential to this most important esthetic aspect of treatment. Every case is different. Step 4: Protect or reshape the smile arc The concept of protecting or reshaping the patient s smile arc is a valuable one (Fig. 4), which owes a debt to Dr. David Sarver for its original development and inclusion in the Insignia software. Fig. 3a The software typically employs a flat (0 degree) occlusal plane, so the patient s natural occlusal plane must be taken into account. In most cases, we simply need to protect the smile arc, rather than enhance it. In my early cases, the temptation was to increase smile arc more than necessary, which then required bracket repositions during treatment. Expert tip: Take caution not to overuse the smile-arc feature. Step 5: Determine the lower posterior torques As with any treatment, desired arch form is selected. My choice is the Customized Damon Arch Form. However, any desired arch form can be customized in digital setups. In viewing the setup from the angle of the lower posterior pictured in Fig. 5, it is clear the plan for this case was primarily for up-righting teeth with little translation, if any. According to the Kraus Dental Anatomy and Occlusions, 2 the ideal first molar axial inclination should be 10 degrees, which creates a slight Curve of Wilson (Fig. 6). If you need to deviate from this criterion, it s important to err slightly toward five degrees, rather than 15 degrees. To finalize the lower posterior setup, the software offers templates and symmetry guides for comparing the setup with the Fig. 4 Fig. 3b Step 4: Accepting or adjusting the smile arc in the Approver offers a valuable esthetic enhancement to case finishes. Fig. 5 Figs. 3a and 3b. Step 3: Comparing the setup with the patient s pretreatment lateral images and ceph ensures proper incisor inclination. Note: Diagnostic pretreatment and goal tangents marked on the ceph are not part of the Insignia software. Step 5: The view of the lower occlusal torque setup for this patient shows mainly uprighting with minimal translation, if any. 26 OCTOBER 2015 // orthotown.com

4 feature \\ case presentation Fig. 6 Step 5: If deviating from the ideal molar inclination criteria of 10 degrees, it s important to err slightly toward five degrees rather than 15 degrees. Fig. 7 Step 5: To finalize the lower posterior setup, compare the setup with the arch form of your choice from the various templates offered. arch form of your choice, allowing modification. The lower arch is fitted to the template with the buccal surfaces of the upright molars touching the yellow ruler (Fig. 7). Step 6: Verify anterior torques The highly variable dental anatomy each patient exhibits requires individually customized torques to avoid round tripping/undesired movements often seen with stock prescriptions. Achieving ideal custom torque means the software delivers a near straight-wire approach, essential for efficient sliding mechanics and maximum efficiency (Fig. 8). (See next page.) These values must be verified to ensure they make sense clinically that the upper anterior torques won t flare the teeth inappropriately; that the lower anterior torques aren t too negative; that the symmetry makes sense; and that the torques reflect the planned mechanics, etc. Evaluate the torques to make sure they fit with planned mechanics and personal clinical preferences. If they do not, re-evaluate the digital setup to ensure each tooth position is appropriate. orthotown.com \\ OCTOBER

5 case presentation // feature Fig. 8 Fig. 9 Step 7: Using the digital occlusogram ensures no interferences exist. Fig. 10 Step 6: Verifying the patient-specific torque values ensures effective case management and superior results. Step 7: Validate the occlusion Using the digital occlusogram, validate that there are no interferences (Fig 9). In my early setups, I would begin treatment planning by positioning the teeth for optimum occlusion, realizing later that doing so often created unintentional interferences. When following my recommended sequence, the proper occlusion usually manifests or requires only minimal adjustment and is therefore best manipulated at the end of the setup sequence. Case review This patient was 12 years, 9 months old, and presented with a Class I dental and skeletal occlusion, deep bite with moderate crowding in each arch and severely retroclined upper incisors (Fig. 10). The treatment plan included bite turbos on the upper first molars to disocclude the arches so the early light elastics (3/16- inch 2 oz. L6-U4) would work simultaneously with leveling and aligning the arches. In my hands, early light elastics, especially with passive self-ligating appliances, maximize efficiency and shorten treatment. A button was bonded and chain employed to rotate the lower right second bicuspid, which was later bonded utilizing the bracket placement jig once the tooth had been de-rotated. At placement of.018 x.025 Copper Ni-Ti wires, elastics were changed to Parrot 5/16-inch 2 oz. Repositions included the lower lateral incisors and the lower right second bicuspid to correct rotations and the lower right first bicuspid, which was hyper-erupted (Figs. 11a and 11b). I didn t catch the extrusion because of prematurely manipulating the occlusogram feature. Pretreatment Fig. 11a Figs. 11a, 11b: Midtreatment progress Fig. 11b Conclusion This case treated to an excellent finish with transverse arch development that filled her buccal corridors, a well-maintained smile arc, and beautiful incisor inclination and posterior interdigitation (Fig. 12). The Insignia Advanced Smile Design platform used in this case offered me sophisticated virtual treatment planning and custom-fabricated appliances brackets, wires and positioning jigs that resulted in superior clinical outcomes and greater treatment predictability and profitability for my practice (Fig. 13). 28 OCTOBER 2015 // orthotown.com

6 feature \\ case presentation Fig. 12 Post-treatment Fig. 13 Appliance: Insignia Advanced Smile Design Treatment Time: 12 months Total Visits: Eight including bonding and debonding Treatment Analysis A standardized protocol for setup design one that works from the general to the specific can greatly improve planning and treatment efficiency. References 1. Eastham, R. Relationship of the maxillary incisor to the soft-tissue facial plane. Northwest Angle Society Kraus, BS, Jordan, RE, Abrams, L. Kraus Dental Anatomy and Occlusions Questions for the author? Comment on this article at Orthotown.com/magazine.aspx. Author Bio Dr. Jamie Reynolds earned his dental degree from the University of Michigan and his master s degree in orthodontics from the University of Detroit-Mercy. He is a diplomate of the American Board of Orthodontics and was the first orthodontist to include an Insignia case in his ABO recertification examination. Reynolds lectures nationally and internationally on advanced orthodontic technologies, treatment efficiency and practice management. He has vast experience with Insignia and the Damon System and is also the co-founder of OrthoFi, a software, service and consulting system that helps doctors and patients start more orthodontic treatment. orthotown.com \\ OCTOBER