# Nonsurgical Correction of Anterior Crossbite with Extra-Radicular Miniscrews--A Case Report
## 4 Discussion  
Dentoalveolar protrusion consequent to anterior crossbite correction is quite often in borderline Class III cases. The major tooth movements of anterior crossbite correction are advancement and proclination of maxillary incisors, while the retraction of the mandibular incisors is relatively limited. The choice between extraction and non-extraction may lead to a significant difference in the posttreatment profile [48]. An extraction treatment plan may avoid posttreatment protrusion, but risks with a dished-in posttreatment facial profile, especially in an adolescent patient with growth potential. Although the CVM (cervical vertebral maturation) of Case 1 was stage 5, indicated at least one year after the growth peak, late mandibular growth was possible in Case 1 to worsen the facial profile [49; 50; 51; 52]. If orthognathic surgery is considered later after growth completion, there would be a significant round trip for dental decompensions before surgery. Hence, the nonextraction approach, in the beginning, might be more conservative, such as in Case 1. After correcting the anterior crossbite, a reevaluation can be made to check the patient's perception of the facial profile change. Four-premolar extraction or whole arch distalization might be considered if protrusion is a concern. With four-premolar extraction, more retraction can be expected. It will take longer to close the extraction spaces. If the patient hesitates to extract premolars, extra-radicular miniscrews at IZC and buccal shelf for whole arch distalization might be another option, as in Case 2. The overall cephalometric superimposition is barely able to show the true value of this treatment modality; the serial cephalometric superimpositions and profile photographs need to be examined, too (Figures 17 and 18). In the camouflage treatment of a Class III malocclusion, the mandibular arch is usually the limiting factor in the treatment result. It is more difficult for mandibular dentition distalization than maxillary dentition advancement to correct a negative overjet, so it is common to see proclined maxillary incisors along with retroclined mandibular incisors after Class III camouflage treatment. Furthermore, the posttreatment profile usually looks protrusive. If the whole mandibular dentition can be distalized with miniscrews during treatment to avoid proclination of the maxillary incisors, the posttreatment profile might not look so protrusive. Figure 16: Case 2, Follow-up records after 8 years and 3 months. In Case 2, we can see that even with buccal shelf TSADs, the amount of maxillary incisors advancement is more than the amount of distalization of the mandibular incisors because of the nature of the tooth movement. Labial tipping of the maxillary anterior teeth is much easier than retracting the whole mandibular dentition. That is why the profile looked protrusive after anterior crossbite correction. In this case, we installed another two TSADs at the bilateral infrazygomatic crests to distalize the whole maxillary dentition. Together with the two TSADs at the buccal shelves to distalize the whole mandibular dentition, a more orthognathic posttreatment profile was obtained. We reduced the treatment time to 12 months in Case 2 with the nonextraction approach and TSADs. Nonextraction treatment of some Class III malocclusions with TSADs is conservative and efficient.