Ciensias

premolars would be extracted and an edgewise 0.018 x 0.025 appliance placed to align the teeth and control root parallelism as spaces closed. Treatment procedures
Phase 1 treatment
Chin cup therapy was initiated at 9 years 5 months. An .016 auxiliary wire was soldered to the lingual arch to flare the upper incisors and effectively correct the anterior crossbite. The patient was instructed towear the chin cup appliance while sleeping until she was 12 years old. The orthopedic force was about 500 gm. The patient was cooperative only for the first year, but the anterior crossbite was corrected after 5 months. Because tongue thrust was noticed often during chairside observations from 11 years 6 months, tongue training was given to help the patient develop a normal swallowing pattern. At 12years 3 months, the first premolars were serially extracted, except that in the upper right quadrant the second premolar was erupting toward the palate so it was extracted instead of the first premolar. Phase 2 treatment
A second phase of active treatment with .018 preadjusted edgewise brackets was started to maintain the interincisal angle (126.5°) obtained during chin cup treatment. Treatmentcoincided with eruption of the second molars and was completed at 14 years 5 months (Figure 2A-E). Cephalometric analysis following active treatment indicated that both Ul-FH and FMA had increased (8° and 1.5°, respectively), but the sag-
Figure 1E
ittal jaw relationship maintained its initial ANB angle (0°, Table 1). Superimposition of initial and posttreatment headfilms (Figure 3) showedclosure of the N-S-Ar (cranial base) angle, which indicated a positional protrusion of the mandible. Retention
Retention records taken at 16 years 6 months revealed that the central incisors were in an edge- to-edge relationship and the lateral incisors were in crossbite. Cephalometric analysis showed that ANB and Ul-FH had decreased (-1° and 2.5°, respectively). The initial IMPA of 87° had beenmaintained (Table 1). Superimposition of tracings from 14 years 5 months and 16 years 6 months indicated that protrusion of the mandible was the primary reason for the occlusal changes that occurred during retention (Figure 4). Both maxillary third molars were extracted 2 years after retention records were taken. Phase 3 treatment (retreatment)
At 19 years 1 month (Figure 5A-D), the patient returnedto the clinic for a follow-up screening of chin cup patients.4 She was the only TMJ dysfunction patient who agreed to further treatment. Her symptoms included mild TMJ muscular pain that was commonly present for a few hours in the morning, difficulty with maximum mouth opening, and tongue thrust (possibly associated with muscle pain). There was no audible TMJ clicking.
The following records weregathered to aid in evaluating function: mandibular kinesiograph

Case Report KY: Chin cup patient with TMJ pain
Figure 2A-E Posttreatment facial and intraoral photos, 14 years 5 months
Figure 3
Superimposed cepha- lometric tracings (8 years 9 months and 14 years 5 months)
Figure 4
Superimposed cepha- lometric tracings (14 years 5 months and 16 years 6 months)
Figure 2A Figura 28
Figure 2CFigur« 2D
Figure 2E
After active treatment (14 y 5 m)
After retention {16 y 6m)
Figure 3
(MKG), computer-aided axiograph (CADIAX), and electromyograph (EMG). EMG records were obtained for the closing muscles, the anterior and posterior parts of the temporal and masseter muscles, and the anterior belly of the digastric muscle for the opening muscle.
Based on records taken at 19 years1 month (MKG, CADIAX and EMG), the patient was diagnosed as having myofascial pain associated with balancing occlusal interference of the second molars, TMJ muscular pain, and difficulty in achieving maximum mouth opening.
Treatment objectives were designed to relieve muscle pain and improve occlusal function through comprehensive orthodontic care using edgewise appliances. Splint therapy (flat...