ISSN : 0376-4672
Approximately 30% of adult patients who want orthodontic treatment have transverse discrepancy with insufficient width of the maxilla. Particularly, in Class III patients requiring orthognathic surgery, the frequency of insufficient width of the maxillary arch related to respiratory problems is high. We report a case of non-surgical maxillary expansion using a Hyrax type expander with an orthognathic surgery, based on the reports that the ratio of non-fused midpalatal suture is not high in adults. A 30 years and 2 months old woman with a long face showed an Angle Class III with a vertical growth pattern. Class III molar and canine relation, anterior edge bite, and mandibular incisor compensatory lingual inclination were observed. The posterior buccal overjet seemed to be appropriate, but I diagnosed that there was a transverse discrepancy, for the following reasons. The inter-canine and inter-molar widths were sufficient but excessive lingual inclination of the mandibular molars was observed when assessing the bucco-lingual inclination based on the center of resistance of the maxillary and mandibular first molar. For this reason, it was expected that intercuspal interference would occur during orthodontic decompensation. Therefore, slow maxillary expansion using Hyrax type expander was performed and 2-jaw rotation surgery was performed to improve aesthetic and occlusion. Adults can also improve width discrepancy by non-surgical methods, which can avoid SARPE requiring additional surgery or segmental surgery lacking stability and predictability.
1. Proffit WR, Phillips C, Dann C, 4th. Who seeks surgical-orthodontic treatment? Int J Adult Orthodon Orthognath Surg. 1990;5(3):153-60.
2. Korn EL, Baumrind S. Transverse development of the human jaws between the ages of 8.5 and 15.5years, studied longitudinally with use of implants. J Dent Res. 1990;69(6):1298-306..
3. Knaup B, Wehrbein, H, Yildizhan F. Age-related changes in the midpalatal suture: A histomorphometric study. Journal of Orofacial Orthopedics. 2004;65(6):467-74.
4. Korbmacher H, Kahl-Nieke B, Schilling A, Amling M, P?schel, K. Age-dependent three-dimensional microcomputed tomography analysis of the human midpalatal suture. Journal of Orofacial Orthopedics. 2007;68(5):364-76.
5. Handelman CS, Wang L, BeGole EA, Haas AJ. Nonsurgical rapid maxillary expansion in adults:Report on 47 cases using the Haas expander. Angle Orthod 2000;70:129-44.
6. Bassarelli T, Dalstra M, Melsen B. Changes in clinical crown height as a result of transverse expansion of the maxilla in adults. Eur J Orthod 2005;27:121-8.
7. Janson G et al. Buccolingual inclinations of posterior teeth in subjects with different facial patterns. Am J Orthod Dentofacial Orthop 2004;125:316-22.
8. Fonseca RJ, Marciani R, Turvey T, Oral and maxillofacial surgery 2nd Ed. Chapter 10. Transverse maxillary distraction osteogenesis. Elsvier;2009.
9. Koudstaal MJ, Smeets JBJ, Kleinrensink GJ, Schulten AJM, van der Wal KG. Relapse and Stability of Surgically Assisted Rapid Maxillary Expansion: An Anatomic Biomechanical Study. Journal of Oral and Maxillofacial Surgery. 2009;67(1):10-4.
10. Hershey HG, Stewart BL, Warren DW. Changes in nasal airway resistance associated with rapid maxillary expansion. Am J Orthod. 1976;69(3):274-84.
11. Lehman Jr. JA, Haas AJ. Surgical-orthodontic correction of transverse maxillary deficiency. Dent Clin North Am. 1990;34(2):385-95.
12. Mehra P, Cottrell, DA, Caiazzo A, Lincoln R. Lifethreatening, delayed epistaxis after surgically assisted rapid palatal expansion: A case report. Journal of Oral and Maxillofacial Surgery. 1999;57(2):201-4.
13. Posnick JC. Craniofacial dysostosis: staging of reconstruction and management of the midface deformity. Neurosurg Clin N Am. 2000;2(3):683-702.
14. Phillips C, Medland WH, Fields HW Jr, Proffit WR, White RP Jr. Stability of surgical maxillary expansion. Int J Adult Orthod Orthognath Surg. 1992:7(3);139-46.
15. Stephens CR. An examination of the long-term stability of surgical-orthodontic maxillary expansion, Master’s thesis, Ohio State University, Columbus, 1986.