Faculty Bibliography

INTRODUCTION/BACKGROUND:Simultaneous Le Fort III/I (LF III/I) osteotomies are often performed when a differential advancement of the upper and lower midface is needed. This study aims to evaluate midface position preoperative and 1 week postoperative in patients with severe midface hypoplasia. In addition, this study aims to compare the planned surgical movements to the actual postoperative movements. MATERIALS AND METHODS/METHODS:A retrospective review was conducted using cephalometry for patients treated with a simultaneous LF III/I osteotomy at a single institution. Osteotomies were performed during 1980-2018 on skeletally mature patients with a craniofacial syndrome, with clinical and radiographic follow-up available. RESULTS:Twelve patients met the inclusion criteria with a mean age of 20.2±6.4 years. Treatment resulted in statistically significant anterior movements related to Orbitale, anterior nasal spine, A Point, and the upper incisor tip, and inferior movements related to anterior nasal spine, A Point, upper and lower incisor tips, B point, and pogonion. Stability after 1 year showed only statistically significant changes at ANB. The predictable error for planned movements versus actual movements was greater in the vertical plane than the horizontal plane. CONCLUSIONS:A simultaneous LF III/I osteotomy significantly improved the midface position and occlusal relationship in syndromic patients with midface hypoplasia in a predictable manner. Further multicenter studies with larger sample sizes are needed to validate the conclusions.

PURPOSE/OBJECTIVE:To examine the growth rate discrepancy of the affected and unaffected ramus heights in Pruzansky Type I and Type II mandibles. METHODS:This is a serial retrospective longitudinal growth study of 30 untreated patients (21 males and 9 females) with UCMF (age range from 5 years to 14 years). The mean age of patients was 8.5 years, and the mean follow-up records were 3.7 years. There were 13 patients in group I with a Pruzansky Type I mandible and 17 patients in group II with a Pruzansky Type II. The unaffected side of the mandible served as a control. Eighteen cephalometric parameters were examined at each of the two-time intervals. RESULTS:In patients with Pruzansky Type I mandible, the affected ramus grew on average 1.41 mm per year; the unaffected ramus grew 1.66 mm per year during the same period. In patients with Pruzansky Type II mandible, the affected ramus grew on average 0.84 mm per year; during the same period, unaffected ramus grew 1.79 per year. When the growth rate of the ramus height on the affected side was compared to the unaffected side, there was no statistically significant difference in Pruzansky Type I mandibles (p > .05); however, there was a statistically significant difference in the Pruzansky Type II mandibles (p < .05). CONCLUSION/CONCLUSIONS:The growth rate discrepancy of the affected and unaffected ramus heights was more severe in Pruzansky Type II mandibles than Pruzansky Type I mandibles explaining the progressive nature of facial asymmetry in Pruzansky II mandibles.

ABSTRACT/UNASSIGNED:This is a retrospective study to evaluate the postsurgical position of the maxilla and mandible in 5 matured craniofacial patients with unilateral craniofacial microsomia who underwent 2 jaw surgical procedures using computerized surgical planning. The craniofacial surgeon and orthodontist completed the virtual surgical treatment plan with a biomedical engineer's assistance via a web meeting. The treatment plan of each patient included 2 jaw surgery with genioplasty. At the maxillary dental midline, the planned mean advancement was 4 mm; yaw, a rotational correction towards the unaffected side was 4.96 mm; and impaction was 2.74 mm. The mean advancement measured at point B was 10.5 mm, and the rotational correction towards the unaffected side was 6.58 mm. The mean advancement following genioplasty was 8.43 mm, and the mean transverse correction was 6.33 mm towards the midsagittal plane. The intermediate surgical splint, final surgical splint, bone graft templates, and cutting guides were constructed utilizing computer-aided design/computer-aided manufacturing technology. The surgeon executed the treatment plan in the operating room using appropriate computer-generated guides and splints. A postsurgical cone-beam computed tomography scan was obtained and superimposed on the surgical treatment plan using Simplant OMS 10.1 software. The cranial base was used as a reference for superimposition. Three-dimensional color-coded displacement maps were generated to visually and quantitatively assess the surgical outcome. There was a mean error of 0.88 mm (+0.30) for the position of the maxillary anatomical structures from the planned position, and the anterior mandibular anatomical structures were on average 0.96 mm (+0.26) from the planned position.

Background/Purpose: Our study quantifies changes in skeletal, soft tissue profile, and globe position in patients with syndromic craniosynostosis after Le Fort I + III (LF I + III) surgery. Methods/Description: Patients with syndromic craniosynostosis who underwent LF I + III at the time of facial maturity were followed for at least 1 year. Each lateral cephalometric radiograph was traced using Dolphin Imaging software and superimposed at the sella. Changes in positions of the different landmarks at T0 (preoperatively), T1 (immediate postoperatively), and T2 (1 year postoperatively) were measured by the software. Sixty-seven soft tissue and skeletal landmarks were digitized and measured. LF III skeletal changes were measured by changes in lateral orbit and orbitale. LF I skeletal changes were measured at the A point and U1. Corresponding soft tissue profile and globe position were studied. All data were measured along the x-axis.
Result(s): Twelve patients included in our study have the following syndromes: Crouzon (n = 6), Pfeiffer (n = 2), Apert (n = 1), Antley-Bixler (n = 1), cleidocranial dysplasia (n = 1) and frontonaso dysplasia (n = 1). Nine patients had previous history of LF III distraction. Standard descriptive statistics was used. Data were analyzed using paired T test. Lateral orbit advanced 5.49 mm (T0-T1) on average, with a P value of 1.3-5, and 5.94 mm (T0-T2) on average; 0.45 mm (T1-T2) change with a P value of .96 suggests the lateral orbit is stable. Similar advancement at orbitale is observed at 5.68 mm (T0-T1) and 6.42 mm (T0-T2). The globe moved anteriorly by 1.98 mm (T0-T1) with a P value of .025 and anteriorly by 0.944mm(T0-T2). The change between T2 and T1 is 1.04 mm (P value: .26), which suggests the globe moved backward after postsurgical swelling subsided. The ratios of movement (globe to lateral orbit) between T0-T1 and T0-T2 are 31% and 16%, respectively. The decrease in ratio can be attributed to the reduction in soft tissue swelling at T2. Restoring position of the globe relative to the lateral orbit decreases the risk of exposure keratitis, keratoconjunctivitis sicca, and corneal ulceration. Anterior nasal spine and point A were advanced by 9.38 and 10.08 mm, respectively, between T0 and T1, and 9.01 mm and 8.51 mm, respectively, between T1 and T2. At the occlusal level, U1 advanced 10 mm and L1 moved back 1.45 mm between T0 and T1. Menton moved back 1.25 mm (T0-T1) but advanced by 2.48 mm (T0-T2). This change in direction is due to splint use at T1 as it rotates mandible clockwise.
Conclusion(s): In our cohort, LFI + III surgery improved both midface deficiency and proptosis in those with syndromic craniosynostosis.Combined Le Fort I + III surgery allows surgeons to perform differential corrections of the midface at the orbital and the dentition level. This is ideal for proptosis correction and establishing optimal jaw relationship

INTRODUCTION/BACKGROUND:LeFort III distraction osteogenesis may be indicated in the treatment of syndromic craniosynostosis with severe midface retrusion. This study investigates long-term changes in patients undergoing distraction as children, and compares outcomes to an unaffected, untreated control. METHODS:Fifteen patients (9 males, 6 females) with syndromic craniosynostosis treated by LeFort III distraction at an average age of 4.9 ± 1.5 years were identified. Lateral cephalograms at predistraction, immediate, 1-, 5-, and 10-year postdistraction were superimposed using the best-fit of cranial base details. An untreated, unaffected matched control was obtained from the American Association of Orthodontists Foundation Legacy Collection. Differences in landmark location and cephalometric relationships were assessed between time points and between treatment and control groups. RESULTS:LeFort III distraction produced an average advancement of 14.86 ± 5.14 mm at A-point and 10.54 ± 3.78 mm at orbitale. This advancement produced overcorrection of anteroposterior occlusal relationships and phenotypic correction of midface position. Surgical stability over a 10-year follow-up was excellent. Posttreatment growth was characterized by absent anteroposterior maxillary growth, preservation of dentoalveolar development and maxillary remodeling, and delayed mandibular growth. Subsequent growth resulted in a long-term phenotypic relapse of pretreatment Class III maxillomandibular relationship and negative overjet. CONCLUSIONS:LeFort III distraction osteogenesis produces stable advancement of the midface. Overcorrection is required for long-term phenotypic stability because of deficient postdistraction sagittal midface growth. Late mandibular growth contributes to underestimation of the amount of distraction required to produce long-term phenotypic correction.

BACKGROUND:Le Fort III advancement and/or distraction involve osteotomies and dysjunction in the region of the maxillary tuberosity in proximity to the maxillary posterior tooth buds. The purpose of this study was to determine the effect of early conventional Le Fort III advancement and/or distraction on development and eruption of the maxillary posterior permanent molars. METHODS:A retrospective review of patients diagnosed with syndromic craniosynostosis, who underwent early Le Fort III or early midface distraction and late surgical intervention, was analyzed. RESULTS:In the early conventional Le Fort III surgery group, 93 percent of maxillary second molars and 28 percent of maxillary first molars experienced a disturbance in eruption. In the early distraction group, 82 percent of maxillary second molars and 20 percent of maxillary first molars experienced a disturbance in eruption. In the control group, the late conventional Le Fort III and the late distraction groups, only 26 percent of maxillary second molars and none of maxillary first molars experienced a disturbance in eruption. CONCLUSIONS:A common disruption seen postoperatively in the early Le Fort III and distraction groups was displacement of the second molars. The majority of the displaced tooth buds were located in the maxillary sinus. Overall, the early Le Fort III surgery groups experienced more frequent disturbances for both first and second molars, with the common sequela of displacement in the maxillary sinus, leading to the question of whether presurgical planning in cases of early intervention to address midface retrusion should include extraction/enucleation of the second molar tooth buds. CLINICAL QUESTION/LEVEL OF EVIDENCE/METHODS:Therapeutic, III.

INTRODUCTION/BACKGROUND:Treacher Collins syndrome (TC) and Pierre Robin sequence (RS) are associated with hypoplastic mandible, glossoptosis, and consequent airway obstruction. Although TC and RS are often grouped together, airway outcomes of bilateral mandibular distraction osteogenesis (MDO) have not been specifically studied in TC. The purpose of this study is to report on the clinical outcomes of MDO in the TC patient population. MATERIALS AND METHODS/METHODS:A twenty-year single-institution retrospective review of all patients with TC who underwent bilateral MDO was performed. Twenty-four patients were identified after exclusion due to different diagnoses or insufficient medical records. Data on comorbidities, airway status, MDO operations, and complications were collected. Data were compared with published clinical outcomes in RS and data for 13 RS patients from our institution. RESULTS:Surgical success, defined as prevention of imminent tracheostomy or successful decannulation within 1 year after primary distraction, was observed in 21% of TC patients and 65% of RS patients (P = 0.01). Repeat distraction was necessary for 11 TC patients (46%) and 1 RS patient. Complications were divided into minor, moderate, and major based on need for invasive management. Overall, 67% of TC patients had complications, 20% of which were major. CONCLUSIONS:Clinical outcomes to airway function after MDO are significantly inferior in patients with TC compared with patients with RS. Repeat MDO and longer course to decannulation are more prevalent in patients affected by TC.

Le Fort III distraction osteogenesis may be indicated in the treatment of syndromic craniosynostosis with severe midface retrusion and proptosis. This study assesses the stability of proptosis correction over 10-years.A retrospective review identified 15 patients with syndromic craniosynostosis treated by Le Fort III distraction prior to age 10 (9 males, 6 females; age 4.9 ± 1.5 years). Untreated, non-craniosynostotic age- and gender-matched controls were obtained from historical growth records. Lateral cephalometric tracings at pre-surgery (T1), immediate (T2), 1 year (T3), 5 years (T4), and 10 years (T5) (n = 11) post-distraction were superimposed using the best-fit of cranial base. Proptosis severity was defined as the horizontal distance between the Ant. Globe cephalometric point and orbital rim landmarks Orbitale and Lat. Orbit.The orbital rim advanced 10.54 ± 3.78 mm (P < 0.001) at Orbitale and 9.73 ± 4.54 mm (P > 0.001) at Lat. Orbit from T1 to T2; Ant. Globe advanced 3.13 ± 3.02 mm (p 0.001). Proptosis decreased 7.41 ± 5.29 mm (P < .001) from Orbitale and 6.60 ± 6.50 mm (p 0.002) from Lat. Orbit. Comparison to controls demonstrated phenotypic correction. In craniosynostotic patients from T2 to T5, the bony orbital rim demonstrated non-significant remodeling posteriorly and inferiorly. Anterior Globe moved 3.79 ± 1.47 mm anteriorly (P < .001), which did not differ significantly from controls. Proptosis increased by 4.18 ± 2.94 mm in craniosynostotic patients from T2 to T5.Le Fort III distraction was stable, with no significant anteroposterior relapse of the maxilla or bony orbit. Phenotypic relapse of proptosis to pre-treatment levels occurred through deficient growth of the midface, surface resorption at the orbital rim, and preservation of normal forward movement of Ant. Globe.

A retrospective Institutional Review Board-approved review was performed at the Institute of Reconstructive Plastic Surgery, NYU Langone Medical Center, of patients undergoing craniofacial distraction osteogenesis procedures using the rigid external distractor device between 2000 and 2010. Three particularly challenging cases were identified and are presented here.

BACKGROUND: Maxillary position in patients with syndromic craniosynostosis after midface distraction has been shown to be stable 1 year postoperatively. The purpose of this study is to assess midfacial position in the growing child with craniosynostosis 5 years after Le Fort III advancement with a rigid external device (RED). METHODS: Seventeen consecutive patients were identified to have the diagnosis of syndromic craniosynostosis and who underwent midface advancement. There were 10 males and 7 females, 7 patients had Crouzon syndrome, 5 had Apert syndrome, and 5 had Pfeiffer syndrome. A standard subcranial Le Fort III osteotomy was performed. Cephalometric analysis was performed to assess the position of the maxilla. RESULTS: After device removal, orbitale advanced 13.67 mm along the x axis and downward 1.70 mm along the y axis. A Point advanced 15.97 mm along the x axis and downward 1.14 mm along the y axis. At 1 year post-distraction, both orbitale and A point had advanced an additional 0.47 mm and 0.24 mm along the x axis and downward 0.58 mm and 1.78 mm along the y axis respectively. At 5 years post-distraction, orbitale moved posterior 0.58 mm and A point advanced an additional 2.08 mm along the x axis. Orbitale and A point descended 3.23 mm and 5.2 mm along the y axis respectively. CONCLUSIONS: After Le Fort III advancement with distraction, the maxillary position remains stable and continues to advance minimally along the x axis and demonstrates more growth along the y axis over the long term.