Validity of three-dimensional computed tomography measurements for Le Fort I osteotomy

The purpose of this study was to test the precision and accuracy of three-dimensional (3D) linear measurements for Le Fort I osteotomy, obtained from multi-slice computed tomography (MSCT) and cone beam computed tomography (CBCT) scans. The study population consisted of 11 dried skulls submitted to 64-row MSCT and CBCT scans. Three-dimensional reconstructed images (3D-CT) were generated, and linear measurements (n = 11) based on anatomical structures and landmarks of interest for Le Fort I osteotomy were performed independently by two oral and maxillofacial radiologists, twice each, using Vitrea software; this allows true 3D measurement on 3D-CT images. The results demonstrated no statistically significant differences between the inter-examiner and intra-examiner analyses, and physical and true 3D linear measurements using MSCT and CBCT images. Regarding examiner accuracy, no statistically significant differences were found for the comparisons among the physical and the MSCT and the CBCT linear measurements by either examiner. For examiners 1 and 2, the analysis intra-examiner correlation coefficient ranged from 0.87 to 0.96 and 0.82 to 0.98, respectively, using MSCT, and from 0.84 to 0.98 and 0.80 to 0.98, respectively, using CBCT, indicating almost perfect agreement for all analyses performed. 3D linear measurements obtained from MSCT and CBCT images were considered precise and accurate for Le Fort I osteotomy and thus accurate and helpful for Le Fort I osteotomy planning.     

Multicentre study of operating time and inpatient stay for orthognathic surgery

Orthognathic surgery has advanced considerably since its development in the mid-twentieth century, and in most maxillofacial units mandibular and maxillary osteotomies are routine procedures. However, to enable accurate health planning and costing, and to obtain meaningful consent, it is important to have reliable data for duration of operation and inpatient stay. Virtually every aspect of orthognathic surgery has been researched, but we know of no recent studies that have looked specifically at how long the procedures take and how long patients stay in hospital. We retrospectively studied a sample of patients who had had orthognathic operations at six maxillofacial units in the United Kingdom (UK) to assess these measures. We looked at 411 operations which included 139 bilateral sagittal split osteotomies, 53 Le Fort I osteotomies, and 219 bimaxillary osteotomies. The study showed that the mean (SD) operating time for bilateral sagittal split osteotomy is 2 h 6 min (46 min), 1 h 54 min (45 minutes) for Le Fort I osteotomy, and 3 h 27 min (60 min) for bimaxillary osteotomy. The duration of postoperative hospital stay was also measured. Fifty percent of patients spent one night in hospital after bilateral sagittal split osteotomy, whereas 39% and 9% of patients spent two and three nights, respectively. Forty-five percent of patients spent one night in hospital after Le Fort I osteotomy, whereas 34%, 13%, and 2% spent two, three, and four nights, respectively. Forty-one percent of patients spent two nights in hospital after bimaxillary osteotomy, whereas 34%, 21%, and 3% spent one, three, and four nights, respectively. This data provides evidence for national benchmarks.     

Use of the alar base cinch suture in Le Fort I osteotomy: is it effective?

The alar base cinch suture is often used to mitigate the unfavourable increase in nasal width after Le Fort I impaction or advancement of the maxilla. Recently a number of studies have looked at the stability and clinical outcome of this intervention. We investigated the effect of an alar base cinch suture on the change in width of the alar base after Le Fort I osteotomy using a three-dimensional imaging system. Twenty-eight patients were prospectively randomised into an intervention group where a cinch suture was used, and a control group. The width of the alar base was measured before operation, and then at one, and six months. At six months it had increased from baseline by a median of 2 mm in all patients. The median increase was greater in the control group than in the cinch placement group, but the difference was small. The range in both groups was large, indicating great individual variability. There was an overall reduction in the width of the alar base between one and six months after operation, which indicated some resolution of soft tissue oedema associated with the operation, but the median reduction was small and unlikely to be clinically significant. The preliminary findings suggest that the suture confers little benefit in controlling the width of the alar base of the nose after Le Fort I osteotomy. More recently it has been suggested that procedures using a modified cinch suture may result in greater stability.     

Postoperative skeletal stability and accuracy of a new combined Le Fort I and horseshoe osteotomy for superior repositioning of the maxilla

Postoperative skeletal stability and accuracy were evaluated in a combination of Le Fort I and horseshoe osteotomies for superior repositioning of maxilla in bi-maxillary surgeries in 19 consecutive patients. 9 underwent Le Fort I osteotomy alone (preoperative planned superior movement <3.5 mm). 10 underwent Le Fort I and horseshoe osteotomy (combination group) (preoperative planned superior movement >3.5 mm). The maxilla was osteotomized and fixed with 4 titanium Le Fort plates followed by bilateral sagittal split ramus osteotomy of the mandible, fixed with 2 semi-rigid titanium miniplates. Maxillomandibular fixation was performed for 1 week. Lateral cephalograms were obtained preoperatively, 1 week postoperatively, 3, 6, 12 months later. The changes in point A, point of maxillary tuberosity, and upper molar mesial cusp tip were examined. Discrepancy between the planned and measured superior movement of the maxilla in the Le Fort I and combination groups was 0.30 and 0.23 mm, respectively. The maxillae in both groups were repositioned close to their planned positions during surgery. 1 year later, both groups showed skeletal stability with no significant postoperative changes. When high superior repositioning of the maxilla is indicated, horseshoe osteotomy combined with Le Fort I is reliable and useful for accuracy and postoperative stability.     

Le Fort I osteotomy and soft tissue response: A retrospective cohort study comparing three different techniques

The aim of this study was to evaluate the nasolabial soft tissues effects in three different Le Fort I osteotomy techniques using cone beam computed tomography (CBCT) evaluation of three-dimensional (3D) volume surfaces.A retrospective study was designed, and three groups were evaluated: group 1, patients who underwent conventional Le Fort I osteotomy; group 2, patients who underwent subspinal Le Fort I osteotomy; and group 3, patients who underwent conventional Le Fort I osteotomy with ANS recontouring or removal. CBCT evaluation was performed at two time points: T0, 1 week before surgery; T1, 6 months after surgery.A total of 90 patients were enrolled in this study (group 1: 30; group 2: 30; group 3: 30). Mean maxillary advancement was 4.26 mm. For group 1, mean change in inter-alar width was 2.29 ± 1.57 mm (minimum -2mm; maximum 6.1 mm; for group 2 it was 1.20 ± 1.56 mm (minimum ?1.7 mm; maximum 5.9 mm), and for group 3 was 1.84 ± 1.76 mm (minimum ?2.3 mm; maximum 5.9 mm). For group 1, mean change in alar base width was 1.69 ± 2.32 mm (minimum ?4.8 mm; maximum 6,1 mm); in group 2 it was 0.85 ± 2.08 mm (minimum -4mm; maximum 6 mm), and group 3 was 1.21 ± 1.83 mm (minimum -2mm; maximum 5 mm). Results showed statistically significant differences in nasolabial area (P < 0.001).Within the limitations of the study it seems that subspinal Le Fort I osteotomy should be preferred when the priority is to avoid changes to the nasolabial region.     

Postoperative stability following maxillary downward movement with Le Fort I inclined osteotomy at the lateral nasal cavity wall

Downward movement of the maxilla is regarded as one of the less stable long-term orthognathic surgical procedures. To increase postoperative stability with direct bone contact, the conventional Le Fort I osteotomy was modified with an inclined osteotomy at the lateral nasal cavity wall. The aim of this study was to evaluate the postoperative stability of the new method for Le Fort I inclined osteotomy for downward maxillary movement.The study included 27 patients with anterior vertical deficiency of the maxilla who underwent Le Fort I inclined osteotomy for downward maxillary movement. Patients were classified into two groups according to the amount of downward movement. The amounts of relapse (cephalometric changes) of the two groups were compared and statistically analyzed.The mean amount of relapse was about 1 mm. The tendency of relapse was not increased by a large initial downward movement with Le Fort I inclined osteotomy. Le Fort I inclined osteotomy was used safely for downward movement in order to increase bone height at the piriform aperture area and resulted in direct bone contact, suggesting it is a useful technique for maintaining postoperative stability. A further study with a larger number of patients is necessary.     

Simultaneous hybrid of maxillary Le Fort I halo distraction and mandibular set-back for patients with severe cleft jaw deformity

One of the surgical tactics and retrospective chart review of clinical cases are described for severe maxillo-mandibular discrepancy. The recently developed Le Fort I Halo distraction combined with mandibular sagittal splitting osteotomy is initially carried out simultaneously. Materials include six adult patients revealing severe jaw deformity with mandibular prognathism somehow ranging from 17-19 years of age. The required adjustment of the maxillo-mandibular discrepancy ranged from 14-23 mm to obtain the preferred occlusion. The simultaneous combination of over 10-mm maxillary Le Fort I Halo distraction with mandibular set-back secured rigidly by sagittal splitting was accomplished. The amount of mandibular set-back ranged from 4-6 mm. The amount of maxillary Le Fort I halo distraction ranged from 10-17 mm (Table I). The retention period of the halo brace was 21-22 days. In addition, the Delair type of face mask was used for 3-4 months as a night splint for consolidation after removal of the halo brace. Satisfactory maxillary distraction and mandibular set-back as planned preoperatively was obtained in all six cases. No particular postoperative complications were noticed. Compared with standard Le Fort I advancement for cleft patients, more advancement can be obtained easily with halo distration, particularly in cases where a large amount of advancement > 10 mm is required. This combination is worthwhile for a severe cleft jaw deformity, and is an alternative for standard double jaw osteotomy.     

The skeletal stability after maxillo-mandibular osteotomy with a “physiological positioning strategy”

The aim of this study was to estimate skeletal and dental stability after maxillomandibular osteotomy with physiological positioning. Ten patients (7 men and 3 women) with skeletal mandibular prognathism were treated by conventional Le Fort I osteotomy for the maxilla and unfixed short lingual osteotomy for the mandible together with physiological positioning. We used cephalometric analysis to evaluate the skeletal and dental stability preoperatively, immediately after maxillomandibular osteotomy, and more than 1 year later. The immediately postoperative measurements for the SNA and the SN-palatal planes were 0.15^o (p = 0.67) and 1.0 ^o (p = 0.17), respectively. The positions of the anterior nasal spine, posterior nasal spine, and A point showed minimal changes 1 year postoperatively. The postoperative difference for SNB was 0.76 ^o (p = 0.04). Dental stability was apparent postoperatively. We conclude that reliable stability of both the maxilla and the mandible was achieved after maxillomandibular osteotomy with physiological positioning in patients with mandibular prognathism.     

Assessment of lateral pterygoid muscle and temporomandibular joint disc after Le Fort I osteotomy with and without intentional pterygoid plate fracture and sagittal split ramus osteotomy in class II and class III patients

The aim of the study was to examine lateral pterygoid muscle (LPM) and temporomandibular joint (TMJ) disc before and after Le Fort I osteotomy with and without intentional pterygoid plate fracture and sagittal split ramus osteotomy (SSRO) in class II and class III patients.Le Fort I osteotomy and SSRO were performed in class II and class III patients. LPM measurements using oblique sagittal computed tomography (CT) images and TMJ disc position using magnetic resonance imaging (MRI) were examined. Statistical comparisons were performed for the LPM and TMJ between class II and class III patients and between those with and without intentional pterygoid plate fracture in Le Fort I osteotomy.The subjects comprised 60 female patients (120 sides), with 30 diagnosed as class II and 30 as class III. Preoperatively, the width of the condylar attachment, width at eminence, length of the LPM, angle of the LPM, and square of the LPM were significantly smaller in the class II group than in the class III group (p < 0.05). After 1 year, the width of the condylar attachment, width at eminence, and angle of the LPM remained significantly smaller in the class II group than in the class III group (p < 0.0001). TMJ disc position was significantly related to the width of the condylar attachment of the LPM, both pre- and postoperatively (p < 0.0001). However, postoperative disc position did not change in all patients. Next, the class II patients (60 sides) were divided into two groups who underwent Le Fort I osteotomy with or without intentional pterygoid plate fracture. Changes in all measurements of the LPM showed no significant differences between these two groups.Our study suggested that TMJ disc position classification could be associated with the width of condylar attachment of the LPM before and after surgery, while the surgical procedure, including Le Fort I osteotomy with intentional pterygoid plate fracture, might not affect postoperative LMP or disc position in class II patients.     

Maxillary stability following Le Fort I osteotomy in combination with sagittal split ramus osteotomy and intraoral vertical ramus osteotomy: a comparative study between titanium miniplate and poly-L-lactic acid plate.

PURPOSE: The purpose of this study was to compare changes in maxillary stability after Le Fort I osteotomy with titanium miniplate and poly-L-lactic acid (PLLA) plate (Fixsorb-MX; Takiron Co, Osaka, Japan). PATIENTS AND METHODS: The subjects were composed of 47 Japanese patients with diagnosed jaw deformity: 24 underwent Le Fort I osteotomy and sagittal split ramus osteotomy (SSRO); and 23 underwent Le Fort I osteotomy intraoral vertical ramus osteotomy without internal fixation. Each group was divided into titanium plate and PLLA plate groups. Time course changes between plate groups were compared using lateral and posteroanterior cephalography. RESULTS: Significant differences were identified between titanium plate and PLLA plate groups in A point after Le Fort I osteotomy and SSRO (P < .05). Significant differences existed between titanium plate and PLLA plate groups in vertical component of posterior nasal spine after Le Fort I osteotomy in both combinations with SSRO and intraoral vertical ramus osteotomy (P < .05). However, no significant differences were identified in measurements on posteroanterior cephalography. CONCLUSION: These results suggest a slight tendency for vertical impaction after Le Fort I osteotomy both in combination with SSRO and intraoral vertical ramus osteotomy with PLLA plates, although differences in time course changes were not clinically apparent, and normal occlusion was established in all patients.     

Linear and angular measurement using cone-beam computed tomography to enhance safety in Le Fort I osteotomy with tuberosity cut

Clinical Oral Investigations - The study aimed to evaluate surgical angles for tuberosity cut and linear and angular measurements for all horizontal cuts in Le Fort I osteotomy using cone-beam...     

牵引成骨术治疗青少年上颌骨严重发育不足的初步报告

目的 通过青少年上颌骨严重发育不足,特别是继发于唇腭裂术后严重畸形者行改良Ｌｅ Ｆｏｒｔ Ｉ型截骨,并通过颅骨外固定上颌骨牵引成骨前移术,对牵引成骨后硬组织改建及腭咽闭合功能进行初步探讨。方法 采用颅骨外固定牵引装置（ＫＬＳ－ＭＡＲＴＩＮ公司提供）对６例１１～１５岁唇腭裂术后继发上颌骨严重发育不足及发育性上颌骨严重后缩畸形的青少年实施牵引成骨术。运用正颌外科电脑分析软件对术前、术后头颅定位Ｘ线侧位     

Alterations of upper airway volume caused by Le Fort III osteodistraction in children

PurposeThe aim of the study was to assess changes in the upper respiratory tract and sleep quality in patients who were suffering from midfacial hypoplasia and treated with the movement of underdeveloped middle segment of the face with an Le Fort III osteotomy and distraction.MethodsIn this study patients aged 7–19, suffering from Crouzon syndrome, Apert syndrome, or other craniosynostosis were treated with Le Fort III osteotomy and midface distraction. Patients were subjected to radiological examination and polysomnography before and after the treatment. Typical anthropometric points were identified on lateral cephalograms, and were used to take linear and angular measurements. The surface and the volume of the upper respiratory tract were measured with the Dolphin Imaging software. Apnoea Hypopnea Index (AHI) was used to assess the sleep quality.ResultsIn all 18 patients the analysis showed statistically significant changes of the AHI and in the linear, angular and volumetric measurements. Mean change of the volume of the upper respiratory tract was 12,4 ± 11,3cm3(p = 0,0001) and of the surface was 615 ± 521 mm² (p = 0,0000000002). Mean improvement of AHI was 9 ± 6,2 (p = 0,00006). In three cases patients had tracheostomy prior to operation and none of them required tracheostomy after the operation.ConclusionsThe use of distraction osteogenesis of the middle segment of the face combined with Le Fort III osteotomy results in dilation of the upper respiratory tract at the nasopharyngeal level and at the soft palate level resulting in elimination of sleep and respiration disorders. Further studies with polysomnography are necessary, as well as observation of patients over time and monitoring of treatment stability.     

Orbital volume and surface after Le Fort III advancement in syndromic craniosynostosis

There are no quantitative standards for the volumetric measurements of the orbital cavity after Le Fort III advancement. Computed tomography (CT) scan images have given the opportunity to compare with accuracy the real anatomic changes and potentially the functional improvements that resulted after a surgical treatment.Three-dimensional CT scan images processed by DICOM files in Dolphin 3D Software were used to assess orbital volume and surface in 12 subjects affected by craniofacial syndromic malformations treated with Le Fort III advancement. The preoperative (T0) and postoperative (T1: 6 months after surgery) three-dimensional craniofacial CT scans of the subjects were collected and retrospectively analyzed. Image segmentation of the anatomic orbital cavity and the three-dimensional graphic rendering were done by using the Dolphin Imaging Plus 11.0 software.The orbital volume was increased after surgery, with statistical significance, from 22,267 to 22,706.3 mm(3) in the right eye and from 26,511 mm(3) to 26,256.4 mm(3) in the left eye. The surface of both bony orbits had an expansion, which is statistically significant. In conclusion, this study showed that the orbital advancement in white subjects after Le Fort III advancement was significant and produced a significant augmentation of the orbital volume and surface area with correction of the ocular bulb proptosis.     

Stability after Le Fort I osteotomy in cleft lip and palate patients

Le Fort I osteotomies were performed in 20 patients with cleft lip and palate as a one-segment movement, and the fragments were fixed with miniplates without bone grafting. Tracings of preoperative and serial postoperative lateral cephalograms were used to determine changes in maxillary position. The posterior nasal spine, not subjected to extensive changes during surgical procedures and remodeling, was found to be the most reliable landmark for measuring maxillary advancement and stability. The mean maxillary advancement was 5.96 mm. Analysis did not reveal significant changes in linear and angular measurements from immediately postoperative to 6 months postoperative. A modest maxillary advancement by Le Fort I osteotomy, along with alleviation of palatal scar tissue tension and miniplate fixation, is a stable surgical method in patients with cleft lip and palate.     

上颌骨Le Fort I型截骨进路切除巨大鼻咽纤维血管瘤

目的:探讨上颌骨LeFortI型截骨进路切除累及翼腭凹、颞下凹巨大鼻咽纤维血管肿瘤的可行性。方法:采用矫正上颌骨先天或后天畸形的LeFortI型截骨术式进路,切除位于鼻咽部、筛窦等深在部位的纤维血管瘤。结果:该进路术野显露充分,取得了理想的治疗效果。结论:上颌骨LeFortI型截骨进路是切除鼻咽、颅底部纤维血管瘤的理想进路。     

Dynamic analysis of maxillary perfusion during Le Fort I osteotomy using indocyanine green

The aim of this study was to evaluate the dynamic perfusion of the maxilla during various stages of a Le Fort I osteotomy using indocyanine green (ICG) dye angiography. This was a retrospective evaluation of patients who underwent a Le Fort I osteotomy. ICG was used to assess perfusion at specific time points during the procedure. Twenty-four patients underwent a Le Fort I osteotomy with dynamic perfusion ICG angiography. Statistically significant differences in perfusion were noted at all three locations assessed between preoperative (T0), post down-fracture (T1), and postoperative (T2) time points. When controlling for mean arterial pressure, statistically significant differences were noted at all three locations assessed between T0 and T1, and between T0 and T2. There were no statistically significant differences in patient age, heart rate, preservation or sacrifice of the descending palatine arteries, or conventional vs. segmental Le Fort I osteotomies across T0, T1, and T2. In conclusion, there was a statistically significant decrease in perfusion, as assessed by intraoperative dynamic angiography, to the anterior maxilla following maxillary down-fracture. Patient age, conventional vs. segmental Le Fort I osteotomy, changes in mean arterial pressure and/or heart rate, and preservation of the descending palatine vessels had no statistically significant effect on perfusion.     

Condylar and temporomandibular joint disc positions after mandibular osteotomy for prognathism

PURPOSE: The purpose of this study was to compare the changes in temporomandibular joint (TMJ) morphology and clinical symptoms after sagittal split ramus osteotomy (SSRO) and intraoral vertical ramus osteotomy (IVRO) with and without a Le Fort I osteotomy. PATIENTS AND METHODS: Of 43 patients with a diagnosed jaw deformity, 20 underwent IVRO without internal fixation and 23 underwent SSRO with rigid internal fixation. Some operations were performed in combination with a Le Fort I osteotomy. The TMJ symptoms and joint morphology, including the disc position, were assessed preoperatively and postoperatively using magnetic resonance imaging (MRI) and axial cephalography. RESULTS: A significant difference in the direction of condylar rotation was seen in horizontal axial cephalography images (P <.01). Fewer or no TMJ symptoms were reported postoperatively by 88% of the patients who underwent IVRO with or without a Le Fort I osteotomy and by 66.7% of patients who underwent SSRO with or without a Le Fort I osteotomy. In sagittal images, no change was seen in anterior disc displacement after SSRO; however, improvement was seen in 44.4% of patients with anterior disc displacement who underwent IVRO with or without a Le Fort I osteotomy. CONCLUSION: These results suggest that SSRO does not improve anterior disc displacement; IVRO improves anterior disc displacement in the initial postsurgical period, and both procedures may improve TMJ symptoms.     

Orbitofrontal monobloc advancement for Crouzon syndrome

IntroductionUsually, patients suffering from Crouzon syndrome have synostosis of coronal sutures, exophthalmia, hypertelorism, and hypoplasia of the middle third of face. Sometimes maxillary retrusion is absent, so these patients have class I or II relationship. In these cases, frontofacial monobloc advancement, which is the gold standard, increases the maxillo-mandibular dysmorphia. Therefore we propose orbitofrontal monobloc advancement minus dental arch, without splits of the pterygoid plates.Case reportA 12-year-old girl with Crouzon syndrome had intracranial hypertension, exophthalmia, a middle third retrusion and a class II occlusion. We achieved orbitofrontal monobloc advancement which is frontofacial monobloc advancement minus maxillary dental arch. Four distractors KLS Martin were used. After 20 days of distraction, the final advancement was 10.2 mm for cranial distractors and 10.5 mm at fronto-zygomatic. Distractors were removed after 8 months.DiscussionWe offer patients suffering from Crouzon syndrome with class I or II relationship a change from the classic frontofacial monobloc advancement leaving the maxillary dental arch in place, thus avoiding the worsening of the maxillo-mandibular dysmorphia related to surgery. The idea of associating Le Fort I osteotomy with a frontofacial monobloc advancement or Le Fort III osteotomy has already been described, mainly by Tessier and Obwegeser, however they probably achieved a complete Le Fort I osteotomy while we don't split the pterygoid plates.The patient's morphology and his surgical history determine the choice between Le Fort III and monobloc advancement. Dental occlusion needs to be taken into account for surgical indication.     

Effects of maxillary advancement and impaction on nasal airway function

The effects of Le Fort I osteotomy on the nasal airway are controversial. This study aimed to evaluate nasal airway changes after Le Fort I. 25 patients underwent conventional Le Fort I osteotomy and were separated into three groups depending on the type of surgery they underwent. 11 patients needed maxillary impaction, 9 underwent maxillary advancement, and 5 had both maxillary impaction and advancement. Rhinological examinations, anterior rhinomanometry and acoustic rhinometry were carried out 1 week before surgery and 3 months after that. Wilcoxon and χ² tests were used for data analysis. The samples included 19 females and 6 males with a mean age of 22.4 ± 3.32 years. Rhinomanometric assessment showed that total nasal airflow was increased from 406 ± 202 ml/s to 543 ± 268 ml/s in all three groups. Significant decrease in nasal airway resistance was seen in all three groups. Acoustic rhinometry revealed a significant decrease in total nasal volume but an increase in the cross-sectional areas of isthmus nasi (IN) and inferior concha. The rhinomanometric measurements showed improvements in the total nasal airflow after Le Fort I osteotomy with alar base cinch suture in cases where the impaction was not higher than 5.5 mm.