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Dental Tribune Middle East & Africa Edition | 4/2016 ORTHO tribune C2 Class II left) were applied (Figs. 14-15). Vertical elastics were used to pro- duce the final occlusion (Fig. 16). The fixed appliances were removed and the corrected dentition was retained with fixed anterior retainers (Mx 3-3, Md 5-5) that were bonded to each toothinbotharches(Fig.5). Appliances andtreatment progress A 0.022” Damon Q® bracket sys- tem (Ormco) was used. The maxil- lary arch was bonded with standard torque brackets, and low torque brackets were selected for the lower anterior teeth to counter the force of ClassIIIelastics(Fig.12). After seven months of active treat- ment,therightmaxillarycaninewas alignedintothearch.Positiveoverjet was achieved and the canting of the lower occlusal-plane (Fig. 10) was im- proved (Fig. 13). Anterior root torque springs (ART) were placed on both the lower anterior teeth and right maxillary canine for early torque control (Figs. 13-14). After eleven months of active treatment, maxil- lary space was closed, but the exces- sive Curve of Spee of the lower arch and the midline deviation were still evident. Clockwise rotation of the mandible corrected the severe Class III relationship on the right side to Class I, but the slight Class III on the left evolved into a Class II molar re- lationship. A .016 x .025 pre-torqued NiTi wire with asymmetrical elastics were used to flatten the Curve of Spee and correct the molar relation- ship in this stage of treatment (Fig. 14). Fromthe12-20monthsoftreatment, a Class III Lshape elastic from the right mandibular canine, and cours- ing under the 2nd premolar bracket to the right maxillary 1st molar was usedforspaceclosureandsettlingof the posterior occlusion (Fig. 15). Sev- en months were required to correct theasymmetricmolarrelationships. In the last two months of treatment, elastics were applied to settle the occlusion: upside down U shape elastics in the anterior and a verti- cal elastics in the second molar area bilaterally were applied to settle the final occlusion (Fig. 16). After 29 months of active treatment, all ap- plianceswereremoved. Resultsachieved Maxilla(allthreeplanes): •A-P:Maintained •Vertical:Maintained • Transverse: Maintained Mandible (allthreeplanes): •A-P:Retracted • Vertical: Mild clockwise rotation to increasetheverticaldimension •Transverse:Maintained MaxillaryDentition: •A-P:flaringoftheincisors • Vertical: Molar extrusion and me- sialmovement • Inter-molar / Inter-canine Width: Maintained MandibularDentition: •A-P:flaringoftheincisors • Vertical: Molar extrusion and me- sialmovement • Inter-molar / Inter-canine Width: Maintained Facial Esthetics: Retraction of the lowerlipandchinpoint Retention Fixed retainers were bonded on all maxillary incisors and from second premolar to second premolar in the mandibular arch. An upper clear overlay retainer was delivered. The patient was instructed to wear it full time for the first 6 months and nights only thereafter. Instructions in home care and maintenance of retainerswereprovided Finalevaluationoftreatment The ABO Cast-Radiograph Evalua- tion score was 22 points. The major discrepancies were in the lingual occlusal contacts and alignment/ro- tation. Deviation of the lower dental midline was decreased to 1 mm to the left of the maxillary midline. The transposed canine was well aligned, and the gingiva texture was reason- ablyhealthy(Fig.5). Collectively, molar extrusion and mandible clockwise rotation im- proved the facial profile. The Class III molar relation was corrected. Over- all, this Class III asymmetric maloc- clusion was treated to an appropri- ate facial and dental result. The roots of the maxillary incisors were out of focus on the post-treatment pano- ramicradiograph,butitappearsthat there was significant root resorption of both maxillary central incisors and the left lateral incisor. The latter may have been due to the occlusal stress of the premature contact with theanteriorbiteturbosduringcross- bitecorrection. Discussion Surgical correction is routinely in- dicated for asymmetrical Class III malocclusions because of a ques- tionable prognosis for orthodontics only management of large skeletal discrepancies and unsatisfactory es- thetic outcomes.1 However, if there is a substantial functional shift, the asymmetrical profile and mandibu- lar shift are accentuated.2 Increasing lower facial height and correcting the functional shift are more read- ily achieved with nonsurgical treat- ment. Carefully considering the pros and cons of conventional and surgical treatment are important el- ements of diagnosis and treatment planning. Growth potential warrants addition- al consideration if a patient exhibits signs of mandibular overgrowth. In the present case, although the man- dibular prognathism was noted at the beginning of treatment, little or no further increase in mandibular length was noted during treatment. Baccetti3 provided an assessment method for determining skeletal maturation by evaluating the cer- vical vertebrae in routine lateral cephalograms. For the present case, skeletal maturation exceeded CS 5, indicating a mature skeletal pattern, suitable for treatment as an adult. There were additional indicators favoring non-surgical orthodontic options: 1) the chief complaint was mandibular prognathism without considerationoffacialasymmetry,2) reducedlowerfacialheight,3)obtuse nasolabial angle, 4) negative overjet less than 4mm,4 and 5) a moderate Class III molar relationship with a discrepancy that was less than a mo- lar’swidth.5 A conservative treatment approach was selected which consisted of a camouflage dental correction (Fig. 17) with counter-clockwise rotation of occlusal plane. Downward and backward rotation of the chin point, in conjunction with molar extrusion and increased lower facial height, produced a more harmonious lat- eral facial profile. Predictable dental Fig4.Post-treatment facialphotographs Fig. 10. Close-up views of the right maxil- lary canine-premolar transposition and cantingof thelowerocclusalplane. Fig 13. 7th month of treatment. leveling of right maxillary canine and the lower- occlusal plane canting were improved. Positiveoverjet wasalsoachieved. Fig. 14. Asymmetrical elastics and a pre- torque NiTi wire were introduced in the 11thmonthof treatment. (Arrow:lower3-3ART) Fig. 16. Elastics used at the end of treat- ment tosettleocclusion Fig. 11. Premolars were extracted in the initial treatment. Anterior bite turbos were boned on the lower arch for bite opening. Fig.12.ClassIIIelasticprovidedhorizontal and vertical forces to improve canting in the lower arch and to facilitate early cor- rectionofClassIIIrelation. Fig. 15. A L-shape Class III vector elastic wasutilizedforspaceclosure,settlingpos- teriorbiteandbetterinterdigitation. Fig. 17. Camouflage dental correction withcounter-clockwiserotationoftheoc- clusalplane. Table1:Cephalometricsummary Fig5.Post-treatment intraoralphotographs Fig6.Post-treatment studymodels(casts)revealmodest expansioninbotharches Fig7.Pre-treatment panoramic andcephalometricradiographs Fig 9. Superimposed tracings. Reasonable mesial drift of molars and retraction of incisorswerefoundinthisextractioncase. Overjet correction due to maxillary inci- sors uprighting. Well controlled torque of thelowerincisorswerenoticed. Fig8.Post-treatment panoramic andcephalometricradiographs ÿPageC3 ◊PageC1