Splintless surgery using patient-specific osteosynthesis in Le Fort I osteotomies: a randomized controlled multi-centre trial

The accuracy of orthognathic surgery has improved with three-dimensional virtual planning. The translation of the planning to the surgical result is reported to vary by >2 mm. The aim of this randomized controlled multi-centre trial was to determine whether the use of splintless patient-specific osteosynthesis can improve the accuracy of maxillary translation. Patients requiring a Le Fort I osteotomy were included in the trial. The intervention group was treated using patient-specific osteosynthesis and the control group with conventional osteosynthesis and splint-based positioning. Fifty-eight patients completed the study protocol, 27 in the patient-specific osteosynthesis group and 31 in the control group. The per protocol median anteroposterior deviation was found to be 1.05 mm (interquartile range (IQR) 0.45–2.72 mm) in the patient-specific osteosynthesis group and 1.74 mm (IQR 1.02–3.02 mm) in the control group. The cranial–caudal deviation was 0.87 mm (IQR 0.49–1.44 mm) and 0.98 mm (IQR 0.28–2.10 mm), respectively, whereas the left–right translation deviation was 0.46 mm (IQR 0.19–0.96 mm) in the patient-specific osteosynthesis group and 1.07 mm (IQR 0.62–1.55 mm) in the control group. The splintless patient-specific osteosynthesis method improves the accuracy of maxillary translations in orthognathic surgery and is clinically relevant for planned anteroposterior translations of more than 3.70 mm.     

Nasolabial morphology after Le Fort I osteotomies. Effect of alar base suture

This paper describes the effect of an alar base suture in an attempt to gain control of the alar base flaring associated with maxillary advancement and/or maxillary impaction. The suture did reduce alar flaring but it also increased the nasolabial angle. The suture did not significantly influence nasal tip projection.     

Stability and morbidity of Le Fort I osteotomy with bioresorbable fixation: a randomized controlled trial

A randomized controlled clinical trial was conducted to compare the use of bioresorbable and titanium mini-plates and screws in Le Fort I maxillary osteotomies for evaluation of clinical morbidity and stability. Forty patients requiring Le Fort I osteotomies were randomly assigned to two groups. One group underwent bioresorbable mini-plate fixation and the other titanium mini-plate fixation. Stability of the maxilla was determined by serial cephalometric analysis at 2 and 6 weeks and at 3, 6 and 12 months postoperatively. Subjective and objective assessment of clinical morbidity was made prospectively. There were no differences in complications between the two fixation materials. Maxillae with bioresorbable fixation were significantly more mobile at the second postoperative week. Bioresorbable plates were initially more easily palpable, but their palpability decreased with time. Titanium plates became significantly more palpable at the 1-year follow-up. There was no difference in neurosensory disturbance between groups. Patients with bioresorbable plate fixation showed significantly more upward displacement in anterior maxilla following impaction and posterior maxilla following downgrafting from the 2nd to 6th postoperative week. The horizontal and angular relapses in the two groups were comparable. Le Fort I osteotomy with bioresorbable fixation results in no greater morbidity than with titanium fixation up to 1 postoperative year.     

Le Fort I型截骨术上抬上颌骨与下颌骨自动旋转中心的相关性研究

目的:探讨Le Fort I型截骨术上抬上颌骨后,下颌骨自动旋转中心位置变化与上颌骨上抬距离的关系.方法:选取10例患者,均为上颌骨垂直向发育过度导致开唇露齿和下颌骨后下旋转,而下颌骨发育正常,采用单纯Le FortI型截骨术上抬上颌骨,矫正其牙颌面畸形.拍摄术前、术后头颅定位侧位片,利用Reuleaux法测量实际的下颌骨旋转中心位置,应用SPSS10.0软件包对ANS、PNS上抬量与下颌骨自动旋转中心位置进行Spearman秩相关分析.结果:下颌骨平均自动旋转中心位于蝶鞍点下方49.350mm、后方17.100mm处.髁突中心位于蝶鞍点下方24.000mm、后方11.950mm处.下颌骨自动旋转中心垂直向位置与ANS点的上抬量高度相关(P=0.008).下颌骨自动旋转中心垂直向位置与PNS点的上抬量高度相关(P=0.045).结论:下颌骨旋转中心位于髁突外.下颌骨自动旋转中心与上颌骨上抬幅度高度相关.     

下颌骨自动旋转中心与上颌骨上抬量的相关性研究

目的： 探讨Le Fort I型截骨术上抬上颌骨时下颌骨自动旋转中心的位置,下颌骨自动旋转中心与上颌骨上抬量、下颌骨长度和下颌平面角的关系。方法：选取25例单纯采用Le Fort I型截骨术上抬上颌骨矫治垂直向发育过度的患者,测量其术前、术后头颅定位侧位片。利用Reuleaux法测量实际下颌骨旋转中心。采用SPSS13.0软件包对ANS、PNS上抬量、下颌骨长度、MP-SN角度与下颌骨自动旋转中心进行Pearson相关和线性回归分析。结果：下颌骨自动旋转中心平均位于髁突中点下方15.64 mm,后方0.82 mm处。ANS点和PNS点上抬量、下颌骨长度与下颌骨自动旋转中心位置相关,MP-SN角度与下颌骨旋转中心垂直向位置相关。结论：下颌骨自动旋转中心位于髁突外,其与上颌骨上抬量、下颌骨长度和下颌平面角相关。     

The influence of a Le Fort I impaction and advancement osteotomy on smile using a modified alar cinch suture and V-Y closure: a prospective study

A previous report from the authors' department showed that a modified alar cinch suture combined with a muco-musculo-periosteal V-Y closure (mACVY) improves nasolabial mobility. To test if the improvements were equal to the range of nasolabial mobility in non-dysgnathic persons, a prospective study was carried out in 56 patients: 31 with mACVY, 25 with simple closing sutures (SCS) and 18 non-operated, angle class I volunteers. Standardized full facial frontal photographs, taken immediately preoperatively and 18 months postoperatively were used. The landmarks, alare, crista philtri and cheilion were analysed. The test has a standard deviation of 0.9 mm. Intra-group changes, paired t-test, and inter-group differences, unpaired t-test (p<0.05) were statistically analysed. The results show significant preoperative differences in nasolabial mobility compared with the control group, for both groups. Postoperative mobility improved in both groups, but significantly with mACVY with horizontal movement of cheilion and alare, and the vertical movement of crista philtri and less so for the vertical movement of crista philtri with SCS. Postoperative inter-group differences in mobility were small and significant for SCS vs the control group. It can be concluded that using mACVY improves orofacial movement to the level of normal class I volunteers.     

Planning and control of vertical dimension in Le Fort I osteotomies

Depending on the different anatomy of the soft and hard tissues, concavity or convexity of the face, measurements of inferior or superior repositioning of the maxilla may be less predictable when using only the osteotomy site for this calculation. A more reliable method would be to measure the distance from a bone mark in the forehead to the incisor edges. This method has been practiced by our clinic during the past five years. The method is thought to offer a more accurate estimation of the position of the upper anterior teeth in relation to the lip, although one must anticipate a certain degree of postoperative relapse especially concerning inferior repositioning. In order to evaluate the accuracy of our method, a comparison has been made of the calculated vertical repositioning and the surgical results in two groups. In group I (12 individuals) conventional estimation of maxillary repositioning in the osteotomy line was made; in group II (12 individuals) measurements were made from a bone mark on the forehead to the incisor edges. A satisfying correlation was found between calculated and achieved results in both groups. In comparison between calculated and immediate postoperative measurements the results showed no statistically significant difference between the two methods.     

The stability of an alar cinch suture after Le Fort I and mandibular osteotomies in Japanese patients with Class III malocclusions

We previously reported a modified technique for the placement of symmetrical cinch sutures after switching from a nasal to an oral endotracheal tube. We undertook a study to assess the effectiveness of our technique and the stability of changes in the nasolabial morphology after bimaxillary surgery. The study group comprised 30 patients aged 17-36 years who had skeletal Class III malocclusion. All patients had bimaxillary surgery with an alar base cinch suture and V-Y closure. The nasal region was measured directly or on cephalograms before, and 1 week and 1 year after operation. The suture did not alter the width of the alar base, but the nasolabial angle and projection of the tip increased significantly. The length of the upper lip did not change significantly.     

Subnasal modified Le Fort I osteotomy: Indications and results

PurposeTo study the possible morphologic changes in the nose after subnasal modified Le Fort I maxillary osteotomy to correct class III dentofacial deformities in patients with considered normal nasal morphology.Material and methodsFifteen patients (7 males, 8 females) requiring maxillary advancement to treat class III dentofacial deformities were studied prospectively between January 2004 and January 2011. All the patients had an adequate projection of the nasal tip preoperatively preventing a conventional Le Fort I osteotomy. Patients received preoperatively (T1), 6 months after surgery (T2), and 12 months after the initial surgical procedure (T3) lateral cephalograms, CT-3D studies and clinical nose analysis to measure different morphologic variables including: the alar/nose base width, nasal tip protrusion and nasal bridge length using a digital sliding calliper directly on the soft-tissue surface of the face.ResultsMean age was 26.2 years, range 20–36 years. A significant advancement of the maxilla was noted postoperatively (mean 7.5 mm). After surgery the different anthropometric variables of the nasal region analysed had not suffered any significant variation. No significant differences were found when comparing T2 with T3 measures. No significant complications were found.ConclusionThe results indicated that maxillary advancement using a subnasal modified Le Fort I osteotomy can prevent undesirable soft tissue changes of the nose when anterior repositioning of the maxilla is indicated in patients with preoperatively normal nasal morphology.     

A prospective histomorphometric and cephalometric comparison of bovine bone substitute and autogenous bone grafting in Le Fort I osteotomies

Purpose

The aim of the present study was the histomorphometric and cephalometric comparison of autogenous bone grafting of the anterior iliac crest and the application of bovine bone substitute concerning new bone formation and postoperative stability in patients undergoing orthognathic Le Fort I osteotomy.

Incidence of nasolacrimal injury and turbinectomy--associated atrophic rhinitis with Le Fort I osteotomies

Injury to the lacrimal system can occur with trauma, craniofacial surgery, rhinoplasty and nasal antrostomy. Nasolacrimal duct injury may potentially occur with Le Fort I superior repositioning. Atrophic rhinitis is also a potential complication secondary to turbinectomy required during Le Fort I superior repositioning. A review of thirty-four cases over three years of Le Fort I osteotomies with superior repositioning found no postoperative lacrimal injury and no subsequent atrophic rhinitis associated with turbinectomy. An anatomical study relating the position of the nasolacrimal duct opening within the inferior meatus and the distance available for maxillary impaction is reviewed.     

Major vascular complications of orthognathic surgery: hemorrhage associated with Le Fort I osteotomies

Major intraoperative or postoperative bleeding associated with Le Fort I osteotomies can be venous and/or arterial in nature. Arterial hemorrhage generally involves the maxillary artery and its terminal branches. Arterial hemorrhage tends to be more persistent and can be recurrent, which makes it more difficult to manage. Postoperative bleeding following Le Fort I osteotomies generally presents as epistaxis and usually occurs initially within the first 2 weeks following surgery. Treatment modalities that have been used to successfully arrest postoperative hemorrhage include anterior and/or posterior nasal packing; packing of the maxillary antrum; reoperating with clipping or electrocoagulation of bleeding vessels, or the use of topical hemostatic agents in the pterygomaxillary region; external carotid artery ligation; and selective embolization of the maxillary artery and its terminal branches.     

Postoperative skeletal stability at the one-year follow-up after splintless Le Fort I osteotomy using patient-specific osteosynthesis versus conventional osteosynthesis: a randomized controlled trial

The purpose of this study was to assess the 1-year skeletal stability of the osteotomized maxilla after Le Fort I surgery, comparing conventional osteosynthesis with patient-specific osteosynthesis. Patients were assigned to a conventional or patient-specific osteosynthesis group using prospective randomization. The primary outcome was the three-dimensional change in postoperative skeletal position of the maxilla between the 2-week and 1-year follow-up cone beam computed tomography scans. Fifty-eight patients completed the protocol for the 2-week postoperative analysis, and 27 patients completed the 1-year follow-up study protocol. Of the 27 patients completing the entire protocol, 13 were in the conventional group and 14 in the patient-specific osteosynthesis group. The three-dimensional translation analysis showed that the use of the patient-specific osteosynthesis resulted in a skeletally stable result, comparable to that of conventional miniplate fixation. For both the patient-specific osteosynthesis and conventional miniplate fixation groups, median translations of less than 1 mm and median rotations of less than 1° were observed, indicating that both methods of fixation resulted in a stable result for the 27 patients examined. For the Le Fort I osteotomy, the choice between patient-specific osteosynthesis and conventional osteosynthesis did not affect the postoperative skeletal stability after 1 year of follow-up.     

Le Fort I miniplate osteosynthesis: a randomized, prospective study comparing resorbable PLLA/PGA with titanium

The aim of this study was to compare the use of resorbable osteosynthesis material (LactoSorb) with titanium osteosynthesis for the fixation of Le Fort I osteotomies with respect to long-term stability and morbidity. To achieve exact cephalometric measures, five tantalum micro implants were inserted in the maxilla during surgery. A total of 60 patients undergoing a non-segmented Le Fort I osteotomy were randomized to one of the treatments and were followed for 1 year postoperatively. For the osteotomies fixated with LactoSorb, the lateral cephalometric analysis demonstrated a statistically significant difference in the vertical position of the maxilla after 6 weeks as the position became more superior compared with the postoperative situation (mean change of 0.6 mm). In the titanium group no significant changes in position were observed. There were no statistically significant changes in the position of the maxilla from 6 weeks to 12 months in either of the treatment groups. The changes in maxillary postion were not clinically noticeable in either of the treatment groups, and all treatments were completed with satisfactory results. There were two cases of infection and wound dehiscence in the LactoSorb group, whereas titanium osteosynthesis was more often palpable after 6-12 months and required surgical removal in three cases.     

Treatment of maxillary deficiency by a Le Fort I downsliding technique

The treatment of patients with vertical maxillary deficiency by a Le Fort I downsliding technique where the maxilla is moved forward and downward on a planned angulated osteotomy cut, is discussed and the results in nine patients who were treated using this method are reported.