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A Case for Extractions Skeletal and dental Class III treated nonsurgically with Damon™ System Mechanics ByJeffKozlowski,DDS As an orthodontist using Damon™ System (Ormco Corp) passive selfli- gatingbracketsandmechanics,Iam able to treat nearly all of my cases (including a myriad of case types) to exemplary results without extrac- tions. Having said that, extraction therapy is still an important treat- ment option. It is effective when the patient has excessive crowding and protrusion or asymmetrically missing teeth and extractions are preferred to implants. Extractions are especially valuable when orthog- nathic surgery with orthodontics is the preferred treatment plan, but the patient refuses surgery. The case presented here exemplifies such an occasion, employing extraction therapywithorthodonticsinsteadof surgerytogreatadvantage. CasePresentation A female patient age 48 was referred by her dentist to address her crowd- ing and underbite. She had been evaluated years previously for or- thodontics and was told that a com- bination of orthognathic surgery, extractions, and braces was her only treatment option. She presented in my practice with a full-step Class III skeletal and dental malocclusion with an anterior crossbite U2-2 (lat- eral incisors lingually displaced), lower posterior crossbite of the pre- molars, severe lower crowding, pro- clined lower canines, a retrognathic maxilla, and a prognathic mandible. She also presented with generalized mild to moderate gingival recession, but her periodontist cleared her for orthodontictreatment(Figure1).She was open to extractions if surgery couldbeavoided. Treatment Plan Since combined surgical/orthodon- tic treatment was not an option, the plan was to extract lower first pre- molars with the goal of retracting lower anterior teeth into the space provided by the extractions (and out ofcrossbite),usinglightCLIIIelastics to help guide them. Given the lower canine proclination, I believed that any attempt to align the lower ante- rior teeth without extractions would result in further proclination, wors- ening the Class III and negatively affecting the periodontal health of these teeth. After extractions, Da- mon™ Q brackets (Ormco Corp) wouldbeplacedandClassIIIelastics engaged to lower canines to retract them, thus minimizing the ante- rior movement of the lower incisors. Critical to her upper lip/midfacial support, low-torque U2-2 brackets would be used in conjunction with light CL III elastics to prevent crown flaring,helpuprighttheroots (facial- ly), and stabilize lip position. Upper anterior brackets would be placed slightly gingivally to create an ideal smilearc. Treatment Progress The patient was direct-bonded U/L 7-7 with .013” Damon™ Copper Ni- Ti™ wires engaged (Ormco Corp).1 Bite turbos were bonded on L5s to disarticulate the arches and foster maxillary arch development. Lin- gualbuttonswereplacedonU6sand 3.5 oz, 3/16” crossbite elastics (Rab- bit2/Ormco Corp) engaged to assist posteriorcrossbitecorrection. Thepatientreturned4weekslaterto start 2 oz, 5/16” Class III elastics (Par- rot) to begin retraction of the lower anteriors into the extraction sites. At 8 weeks, the crossbite elastics were discontinued and .018” Copper Ni-Ti wires were engaged for further lev- elingandalignment(Figure2).These wires would remain in place for 3 months. Disarticulation would be maintained until the lower anterior teeth were completely out of cross- bite. So problematic was the calculus bridge on the lower anterior teeth (scaled at this appointment), it was preventing lower anterior align- ment. Cleaning was recommended at 3-month intervals, but calculus continuedtoimpedespaceclosure. At 4.5 months, .014” x .025” Copper Ni-Ti archwires were engaged with the bite turbos moved to the lower 6s to add occlusal stability now that the crossbite had corrected. Power chain was added (6/5-3s) to help re- tract the lower 3s. It would be main- tained for 11.5 months, extending 7-7 after 4.5 months. The Class III elastics increased in weight to 3.5 oz (Rabbit). Bite opening in the anterior was due toswitchingturbostolower6s.Light triangle elastics at night might have resolvedthisissue. At 7 months, .018” x .025” Copper Ni- Ti wires were engaged and would be maintained for 13 months in the up- per arch and 11 months in the lower arch. See Figures 3, 4, and 5 (page 70) for treatment progression from 7 to 18months. Also at 7 months, the elastics were switched from Class III to triangle (Rabbit3.5oz,3/16”)foropenbiteclo- sure and would be maintained for 4 months at which time the triangle elastics would remain for an addi- tional2monthsontheleftsidewhen the right side switched to a shorty Class II attachment for 2 months. While the extraction space closure continued with .018” x .025” Cop- per Ni-Ti wires, the ongoing calculus buildup on the lower anteriors con- tinued to impede sliding mechanics and space closure. Light .012” wires were placed in figure 8 under the primaryarchwiresintheanteriorsof the upper arch to consolidate space and prevent its reopening. The .012” wireswouldremaininplaceuntilthe remaining space closed at which timeitwouldextendU/L6-6. Traditionally with Damon System protocols,apanoramicx-rayistaken after .018” x .025” wires are in place for 6 to 10 weeks in order to assess root position and reposition any ap- plicable brackets. In this case to bet- ter visualize the final bracket place- ment, the pano/repo was performed at 15 months (Figure 6, page 70) after most space was closed and all major mechanics complete. The LL5, UR1, and L3-3 were repositioned for ideal placement. At 15 months, a .018” stainless steel wire was placed to allow sliding mechanics for space closure. Using a round stainless steel wire is not typically recommended Damon me- chanics for extraction space closure, but with the ongoing calculus build up and tongue thrust, it was the best course of action. Actually, I would have preferred to use a .016” x .025” stainless steel wire with Ni-Ti retrac- tioncoilsandClassIIIelasticsforlow- erarchspaceclosure.Thiscouldhave saved two to three appointments and a few wire changes, but was sim- plynotfeasibleinthisuniquecase. At 18 months, 3.5 oz, 3/16” (Rabbit) triangleelasticswereengaged(night- time only) for 3 months. A .017” x .025” Damon™ Reverse Curve arch- wire was engaged in the lower arch that would also level curve of Spee. It remained in place for 2 months followed by a .019” x .025” Reverse Curve archwire with 20° of lingual root torque in the anterior segment for 2 additional months. For final Figure1:Pretreatment ofskeletal/dentalClassIIImalocclusion treatednonsurgically. Figure 2: At 8 weeks, the crossbite had sufficiently resolved so crossbite elastics begun at bonding were discontinued as .018” Copper Ni-Ti archwireswereengaged.Note:Acalculusbridgescaledat thisappoint- ment hasbeenpreventingloweranterioralignment. Figure 3: At 7 months, the .018” x .025” Copper Ni-Ti wires had just beenengagedafter2.5monthsin.014”x.025”CopperNi-Tiwires. Figure 4: At 13 months, the .018”x .025”Copper Ni-Ti wires had been engagedfor6months. ÿPage 3 Dental Tribune Middle East & Africa Edition | 4/2016 ORTHO tribune 2