Comparison of Treatment Outcome and Stability Between Distraction Osteogenesis and LeFort I Osteotomy in Cleft Patients With Maxillary Hypoplasia

Abstract

The purpose of this study was to compare treatment outcome and relapse between maxillary advancement surgery with LeFort I osteotomy and maxillary distraction osteogenesis in patients with cleft lip and palate with maxillary hypoplasia. The sample consisted of a maxillary advancement surgery with LeFort I osteotomy group (group 1, N= 14, mean age, 21.7 years) and a maxillary distraction osteogenesis group (group 2, N = 11, mean age, 16.3 years). Lateral cephalograms were taken and traced at presurgery (T0), postsurgery (T1), and postretention (T2). Nine hard and four soft tissue cephalometric variables were measured. Differences in measurements at each stage, treatment outcome (T1-T0), and relapse (T2-T1) were compared between groups with independent t test. Because the amount of surgical movement could affect the amount of relapse, a difference in relapse between two groups was compared by analysis of covariance with the amount of surgical movement as a covariant. Although the amounts of forward movements of A point (P < 0.01), upper incisor (P < 0.001), and upper lip (P < 0.001) during T1-T0 were greater in group 2, there were no significant differences in the amounts of relapse (T2-T1) between the two groups. During T1-T0, counterclockwise rotation of the palatal plane was observed in group 2 as a result of downward movement of posterior nasal spine (PNS) at T1, whereas group 1 had clockwise rotation of palatal plane at T1 because of downward movement of anterior nasal spine (ANS). The amounts of relapse (T2-T1) in vertical movements of PNS and upper incisor were significantly different between the two groups (P < 0.05). The amount of required maxillary advancement, vector control of palatal plane, and vertical position of upper incisor would be important factors when planning a surgical treatment in patients with cleft lip and palate with midface hypoplasia.

Soft Tissue Changes in Cleft Lip and Palate Patients: Anterior Maxillary Distraction versus Conventional Le-Fort I Osteotomy

“…This could very well explain why AMD has greater change in pronasale. Even though studies conducted by Baek et al [11] and Chua and Cheung [13] reported that nasolabial angle increased more in distraction group than in conventional orthognathic surgery, no significant variation was observed in the present study. Nasolabial angle was better improved in AMD group when compared to ALO group.…”

“…Though Cheung et al [6,7,10,11,13] reported no major differences in clinical morbidities between distraction osteogenesis and conventional osteotomy, skeletal and soft tissue stability was better with distraction. The present study goes hand in hand with the results published by Cheung et al For larger movements AMD appears to offer greater stability than that seen with conventional osteotomies.…”

“…Hence AMD was preferred for severe deformity corrections [7]. Moreover alteration in speech and relapse tendency was greater in cases treated with ALO due to tension from palatal scar leading to compromised results [6,7,[10][11][12][13]. Distraction osteogenesis has opened a new perspective in treatment of CLP since 1995 [14].…”

New treatment modality for maxillary hypoplasia in cleft patients

“…38 If the amount of maxillary advancement is large and the patients and parents want a relatively short-term treatment, distraction osteogenesis during adolescence or orthognathic surgery in adulthood can be recommended.…”

Limitations of Internal Distraction Devices in Mature Patients with Cleft Lip and Palate and Severe Midface Hypoplasia

“…One physical reason for the clockwise rotation of the maxilla during distraction even though these distractors were designed to be rigid is that the distraction force was applied above the maxillary center of resistance and so the rotation was introduced by a simultaneous forward movement. In contrast, some external devices are fixed with the teeth and so are below the center of resistance, causing counter-clockwise rotation of the maxilla and additionally offer the advantage to alter the vector during distraction [4,16]. The extreme scarring in our patients after repair of cleft lip palate and after velopharyngoplasty should not be underestimated.…”