Cephalometric evaluation of patients treated by maxillary anterior segmental distraction

Abstract

Background: Maxillary hypoplasia secondary to repaired cleft lips and palates is common. The extent of hypoplasia is dependent on several factors. It is not possible to correct maxillary hypoplasia by conventional orthodontics and relapse is common after orthognathic advancement of the maxilla with or without grafts. Distraction osteogenesis (DO) offers a promising alternative for the management of congenital and acquired facial deformities that require bone lengthening. It is less invasive than traditional surgical techniques, requires less surgical time, and eliminates the need for a donor site operation. In addition, simultaneous soft-tissue expansion may improve long-term skeletal stability. DO allows the body's natural healing mechanisms to generate new bone for augmenting or lengthening bone. The purpose of this study was to enumerate and compare dental, skeletal, and soft-tissue changes, and postoperative stability using cephalometric analysis following anterior maxillary DO in cleft patients. Aims and Objectives: (i) The aims and objectives of this study were to enumerate and compare dental, skeletal, and soft-tissue changes, and postoperative stability using cephalometric analysis following premaxillary DO and (ii) to draw clinical inference from the above results. Methods: Seven female patients underwent anterior maxillary DO with a mean age of 19 years, and the anterior movement of premaxillary segment was generated by tooth-borne distractor with a rapid maxillary expansion screw. The distraction of the premaxilla was stopped after achieving a positive profile and sufficient space to align the maxillary dentition. After the consolidation period, the distractor was removed and orthodontic treatment was started with fixed appliances to level the teeth. Cephalometric data of patients were collected before treatment (T1), after distraction (T2), and 6 months after distraction. Comparison between time periods T1–T2, T1–T3, and T2–T3 were done to evaluate the dental, skeletal, and soft-tissue changes brought by DO. Results: In all the patients, the treatment objective was achieved with a positive overjet and improved profile without changing the position and intermaxillary relation of the posterior. There was a significant horizontal increase of the premaxilla with a definite gain in the maxillary dental arch length for alignment of the maxillary dentition with a downward and backward movement of the mandible. Conclusion: Maxillary DO offers an effective technique to transpose the maxilla forward and downward in moderate-to-severe maxillary retrusion. DO offers better stability due to the gradual expansion and lengthening of the soft tissue in response to the gradual traction. It avoids the complication of acute reconstructive surgical methods and minimal trauma when compared to other alternative surgical methods. It also shortens the overall treatment time due to reduced need for comprehensive treatment time.

Keywords

• anterior maxillary distraction osteogenesis
• distraction osteogenesis
• premaxilla