三维颌骨牵张治疗下颌骨畸形的临床分析

目的:探讨三维颌骨牵张治疗颌骨畸形的临床效果。方法:回顾性分析我院2005年1月-2011年6月收治的颌骨畸形患者42例,根据牵张方法不同分为观察组和对照组,观察组采用三维颌骨牵张,对照组采用平行于矢状轴方向进行牵张,比较两组的牵张效果。结果:术后随访6～24个月,两组牵张时间进行比较,t=7.824,P<0.05,两组牵张时间差异有统计学意义。观察组无牵引器松动而发生发生牵张失败的病例,观察组无失败病例,对照组为6例,占28.57%,x2=4.861,P<0.05,两组牵张失败率差异有统计学意义。观察组与对照组患者咬颌关系(x2=5.091,P<0.05)、颞颌关节(x2=6.431,P<0.05)、颜面外观(x2=4.434,P<0.05)比较,两组差异有统计学意义。结论:三维颌骨牵张法能达到成骨快,成骨质量高的要求,因此在下颌骨正畸过程中适宜采用三维颌骨牵张法。     

关节灌洗术联合透明质酸钠注射治疗颞下颌关节骨关节炎的疗效观察

目的:评价关节腔灌洗联合透明质酸钠注射治疗颞下颌关节骨关节炎(TMJOA)的疗效及安全性。方法:选取我院2014年5月-2015年5月收治颞下颌关节骨关节炎患者68例作为研究对象,根据入院时间先后顺序按照随机数字表法随机分为实验组和对照组各34例。所有患者在颞颌关节区域局麻下建立关节上腔的双通道灌洗系统,实验组用生理盐水反复冲洗关节腔后注射透明质酸钠,对照组只进行关节腔灌洗术,术后随访对比两组治疗前、治疗后4周、6个月时患者非辅助最大开口度、侧向运动幅度、咀嚼时疼痛感;同时采用酶联免疫吸附法(ELISA)测定两组治疗前、治疗后4周血清中白细胞介素6(IL-6)和肿瘤坏死因子α(TNF-α)水平并进行比较。结果:实验组患者治疗后4周、治疗后6个月时颞下颌关节最大张口度和侧向活动距离明显增大,而咀嚼时疼痛感明显减轻,且优于同期对照组,差异具有统计学意义(P0.05);实验组患者治疗后4周时血清IL-6、TNF-α水平较术前及同时期对照组均明显降低,差异具有统计学意义(P0.05)。结论:关节灌洗术联合透明质酸钠注射是治疗颞下颌关节骨关节炎的简单、安全有效治疗方法,治疗效果明显优于单纯关节腔灌洗,值得临床推广应用。     

安氏Ⅱ类2分类错颌治疗后牙及齿槽位置的变化

安氏Ⅱ类2分类错颌是以磨牙远中关系、前牙深覆颌、闭锁颌为特征的一类错颌畸形。安氏Ⅱ类2分类对颞下颌关节功能、牙周组织健康的影响,以及其临床治疗的独特点,对其进行研究具有重要的临床意义。     

钛镍记忆合金牵张器复合脱细胞真皮基质增高犬牙槽嵴的初步研究

目的用成年杂种犬建立钛镍记忆合金牵张器复合脱细胞真皮基质增高犬牙槽嵴动物模型,为下一步利用钛镍记忆合金牵张器行下颌后牙牙槽嵴增高术奠定基础。方法健康成年雄性杂种犬4只。全麻下拔除双侧下颌4个前磨牙和第一磨牙,1个月后拍摄双侧后牙区X线光片,观察拔牙窝愈合情况。采用4种类型的牵张器随机在4只犬的下颌两侧行牵张手术并观察牵张后1周和1月牙槽嵴增高的情况。结果拔牙后1个月,牙槽嵴黏膜愈合良好。X线片示下颌神经管清晰可见,其上方牙槽窝内有较低密度骨质存在。放置4种牵张器牵张术后1周、1月后牙槽嵴增高的高度分别为3.24 mm、3.76 mm、4.58 mm、5.09 mm;3.15 mm、3.67 mm、4.64 mm、5.01mm,术后一周X线可见后有明显的牵张间隙,1月时牵张区有新骨形成,骨密度增高。结论犬耐受力强,后牙区下颌骨体积大,手术易操作,是理想的牙槽嵴萎缩动物模型。拔牙后1个月,拔牙创愈合良好,可以进行牵张手术。D组＂S＂形牵张器牵张后的高度比较理想,能满足后期种植体的植入。     

安氏Ⅱ类2分类错颌治疗后牙及齿槽位置的变化

安氏Ⅱ类2分类错颌是以磨牙远中关系、前牙深覆颌、闭锁颌为特征的一类错颌畸形.安氏Ⅱ类2分类对颞下颌关节功能、牙周组织健康的影响,以及其临床治疗的独特点,对其进行研究具有重要的临床意义[1].     

一种牵张成骨大鼠实验模型的建立

目的建立一种新型SD大鼠胫骨牵张成骨模型的方法。方法 40只雄性SD大鼠右侧胫骨截骨并短缩4 mm,以自行研究设计的环状牵张外固定器固定,于骨折修复期予以牵张外固定器恢复胫骨高度,术后通过大体观察、影像学观察以及组织形态学方法观察截骨部位的愈合与恢复情况。结果术后外固定器稳定有效,对大鼠功能活动无明显影响。胫骨高度恢复,骨性愈合。结论实验所建立的大鼠胫骨牵张成骨模型可靠实用,具有可重复性。     

睡眠剥夺对大鼠行为学及咀嚼肌肌电图的影响

目的：颞下颌关节紊乱病是口腔科的一种常见病和多发病,精神心理因素是颞下颌关节紊乱病的一个主要病因。本文通过观察睡眠剥夺对大鼠行为学及咀嚼肌肌电图的影响,探讨睡眠剥夺在颞下颌关节紊乱病发病中的作用。方法：35只Wistar大鼠,随机分为5组：睡眠剥夺1d组、5d组、9d组、正常对照组和大平台对照组。采用改良多平台睡眠剥夺法（modified multiple plat—formmethod,MMPM）建立大鼠SD模型,观察大鼠行为学及咀嚼肌肌电图的变化。结果：睡眠剥夺1d组和5d组在旷场实验水平得分和垂直得分上均高于对照组,而睡眠剥夺9d组均低于对照组;睡眠剥夺1d、5d和9d组在松弛状态和紧咬状态时颞肌前后束及咬肌的电位均明显高于对照组,且两侧无明显差别,同时,睡眠剥夺组双侧颞肌和咬肌的肌电图静息期较对照组显著延长。结论：睡眠剥夺可使大鼠行为学发生改变并对咀嚼肌肌电图造成影响,这可能是颞下颌关节紊乱病的病因之一,为我们对颞下颌关节紊乱病的预防和治疗提供了一定的理论指导。     

盐酸氨基葡萄糖片联合玻璃酸钠治疗颞下颌关节骨关节炎的疗效观察

目的:研究盐酸氨基葡萄糖片联合玻璃酸钠治疗颞下颌关节骨关节炎(TMJOA)的临床疗效,为临床治疗提供依据。方法:选取2012年11月到2015年11月我院收治的TMJOA患者60例,按照随机数字表法将患者分为研究组和对照组,每组30例,两组均给予玻璃酸钠关节腔注射,研究组在此基础上给予盐酸氨基葡萄糖片治疗,应用视觉模拟评分法(VAS)评价关节疼痛情况,比较两组临床疗效和不良反应,比较治疗前后两组最大张口度、张口VAS评分和张口偏斜。结果:研究组总有效率为83.33%(25/30),显著高于对照组的56.67%(17/30),比较差异具有统计学意义(P0.05);治疗后两组张口VAS评分和张口偏斜显著降低,最大张口度显著增高,且研究组显著优于对照组,比较差异具有统计学意义(P0.05);两组不良反应发生率比较差异无统计学意义(P0.05)。结论:盐酸氨基葡萄糖片联合玻璃酸钠治疗TMJOA具有较好的临床疗效,能有效改善患者关节功能。     

间充质干细胞对颞下关节炎患者血清PRG4 及TGF-beta1 的软骨生成作用比较研究

目的：探讨间充质干细胞对颞下关节炎患者血清PRG4 及TGF-beta1 的软骨生成作用。方法：选取我院颞下颌关节炎患者72 例，随机分为实验组和对照组。对照组予盐酸氨基葡萄糖片口服1 个月，玻璃酸钠注射液颞下颌关节腔每周1 次，注射4 次治疗。 实验组予间充质干细胞培养、自体移植，生理盐水0.5 mL稀释细胞5× 105个关节腔内注射，3 天后再次相同剂量及方式注射。两 组患者分别测定血清TGF-beta1、IL-1alpha和PRG4 蛋白表达，最大张口度测试及疼痛程度评分，并通过影像学检查，评估两组患者关 节组织损伤修复时间。结果：①与对照组相比实验组TGF-beta1 和PRG4 蛋白表达上升更迅速且维持在较高水平，IL-1alpha下降更显 著，差异有统计学意义（P＜0.05）；②与对照组比较，实验组最大张口度增加、张口时疼痛评分下降，差异有统计学意义（P＜0.05）； ③与对照组比较，实验组受损关节组织均修复时间更短，差异有统计学意义（P＜0.05）。结论：间充质干细胞可通过调节血清 TGF-beta1、IL-1alpha水平和PRG4 蛋白表达，促进软骨的生成，对改善预后，提高患者生活质量有重要意义。     

一种新方法获取颞下颌关节骨关节病患者滑膜间充质干细胞及细胞培养鉴定

该研究探讨从颞下颌关节骨关节病患者的关节冲洗液中获取滑膜间充质干细胞(synovial mesenchymal stem cells,SMSCs)并进行体外培养,研究其间充质干细胞特性。采用离心、贴壁培养法从颞下颌关节骨关节病患者的关节冲洗液中提取并分离细胞,进行细胞形态学观察、细胞生长及周期的分析,细胞表面物标志物流式细胞术检测,间充质干细胞标志物免疫荧光检测,成骨、成脂、成软骨多向分化能力检测,促血管分泌因子检测。结果显示,通过离心、贴壁培养法可稳定地从患者颞下颌关节冲洗液中获取滑膜间充质干细胞,体外培养呈对数生长。SMSCs表达间质源性细胞的特异性标记物CD73、CD90、CD105、波形蛋白(Vimentin)以及α平滑肌肌动蛋白的特异性标记物α-SMA。经诱导培养基诱导,SMSCs可分化为骨、软骨和脂肪细胞,细胞分泌液中可检测到如成纤维细胞生长因子(fibroblast growth factor,FGF)、angiopoietin、转化生长因子-β(transforming growth factor-β,TGF-β)等10余种促血管生长因子。以上结果表明,该研究成功建立了以微创的方式获取颞下颌关节骨关节病患者的滑膜间充质干细胞,有望为组织工程应用于骨软骨修复提供良好种子细胞的来源。     

Mandibular distraction in temporomandibular joint ankylosis

Condylar damage during childhood can produce ankylosis and alteration of the mandibular growth. In case of unilateral ankylosis occurring in early childhood, a mandibular hypoplasia of the affected side may develop. The patients have limitation of mouth opening, facial asymmetry, and chin deviation toward the affected side. The aims of this study are to show the use of distraction osteogenesis in mandibular hypoplasia associated with ankylosis and to present our experience with a new therapeutic option for the treatment of mandibular hypoplasia with unilateral ankylosis in the childhood consisting of the association of arthroplasty to treat the ankylosis and mandibular distraction to correct the facial asymmetry, both accomplished in the same surgical procedure. From November of 1996 to November of 1997, three male patients aged 2, 7, and 13 years with mandibular hypoplasia and ankylosis were treated by distraction osteogenesis. An arthroplasty consisting of the resection of the ankylotic block and interposition of a temporalis muscle flap, plus coronoidectomy was done in two of them and mandibular distraction was done in all three patients. Articular functional rehabilitation began on the first postoperative day. Mandibular distraction began on the fifth postoperative day with a rate of 1 mm per day, ending when the facial symmetry was achieved. From the first postoperative day, an increase in the mouth opening was achieved; this increase continued until ending the distraction. The average duration of distraction was 22 days. Average duration of consolidation was 6 weeks. Oral opening increased from 10 mm to 35 mm in the 7-year-old patient, from 9 mm to 27 mm in the 2-year-old patient, and from 14 mm to 38 mm in the 13-year-old patient. To date, oral opening and facial symmetry persist. Osseous mandibular distraction together with arthroplasty offers an excellent new alternative for treatment of patients with mandibular hypoplasia and associated ankylosis, with minimal morbidity and complications.     

Distraction osteogenesis in correction of micrognathia accompanying obstructive sleep apnea syndrome

To evaluate the effect of distraction osteogenesis in correction of micrognathia accompanying obstructive sleep apnea syndrome, a total of 28 patients with different severities of obstructive sleep apnea syndrome underwent mandibular distraction osteogenesis. A total of 51 distraction devices were placed for bilateral distraction in 23 patients and for unilateral distraction in five patients. The mean age of patients was 21.2 years (range, 3 to 60 years). Eleven patients had micrognathia accompanying obstructive sleep apnea syndrome secondary to bilateral temporomandibular joint ankylosis, and 10 patients had micrognathia accompanying obstructive sleep apnea syndrome secondary to unilateral temporomandibular joint ankylosis. Three patients had developmental micrognathia accompanying obstructive sleep apnea syndrome. The other four patients had micrognathia and concomitant obstructive sleep apnea syndrome induced by trauma, infection, or tumor resection. Each patient had been evaluated preoperatively and postoperatively with cephalometry and polysomnography. Mandible advancement ranged from 9 to 30 mm (average, 20.4 mm) and was successfully achieved after distraction. Fine new bone formed in the distraction gap when the distraction devices were removed 3 to 4 months after distraction was completed. No infection or other complications occurred in any patients. Complete curative effects were achieved in nine severe, six moderate, and eight mild obstructive sleep apnea syndrome patients after distraction, and the other five patients had been improved to the mild level. After distraction was completed, the posterior airway space was increased on average from 4.6 mm to 12.5 mm and the sella-nasion-point B angle was increased on average from 66 degrees to 75 degrees on cephalometric studies. The polysomnographic examination showed that the apnea hypopnea index was lowered on average from 58.0 to 3.15, and the lowest oxygen saturation was increased on average from 77 percent to 90.3 percent after distraction was completed. The follow-up period was 3 to 61 months (average, 18.1 months). The curative effect was stable and no relapse occurred. Therefore, the authors conclude that mandibular distraction osteogenesis is an effective method for correcting micrognathia accompanying obstructive sleep apnea syndrome. Compared with other current routine surgical procedures, it has many advantages, such as low risk, simple manipulation, high curative rate, low relapse rate, and stable result. It is presently the most effective method for the treatment of this difficult and complicated disorder.     

Orthognathic surgery in cleft patients

LEARNING OBJECTIVES: After studying this article, the participant should be able to: 1. Identify the skeletal changes in the cleft patient that necessitate surgery. 2. Describe the orthodontic principles that precede surgical treatment. 3. Demonstrate the surgical principles involved in cleft orthognathic surgery and how to avoid common pitfalls particular to cleft orthognathic surgery. 4. Anticipate when dentoalveolar distraction can help in the treatment of problems not easily treated with conventional orthognathic techniques. SUMMARY: This CME article covers the basic multidisciplinary approach to the treatment of patients requiring a combined orthodontic orthognathic approach to their skeletally based malocclusion. The dentoskeletal abnormalities are described for these patients, as are the fundamental orthodontic principles in the presurgical treatment of these patients. The basic surgical principles are discussed in general, and the reader is provided with advice on avoiding common pitfalls. Specific attention is given to the more recent advances in dentoalveolar distraction in cases of large defects that would have been difficult to treat using conventional orthognathic surgery. Videos are provided to illustrate the general principles in treating the cleft orthognathic patient and to illustrate the treatment of large defects using dentoalveolar distraction.     

Distraction osteogenesis of costochondral bone grafts in the mandible

Costochondral grafting for reconstruction of the Pruzansky type III mandible has given variable results. Lengthening of the rib graft by means of distraction had been advocated when subsequent growth of the grafted mandible is inadequate. This retrospective study reviews a series of patients with mandibular costochondral grafts who underwent subsequent distraction osteogenesis of the graft. A retrospective review identified two patient groups: group 1 consisted of individuals (n = 9) who underwent costochondral rib grafting of the mandible followed by distraction osteogenesis several months later at a rate of 1 mm/day. Group 2 consisted of patients with Pruzansky type II mandibles who had distraction osteogenesis without prior rib grafting (n = 9). The biomechanical parameters, orthodontic treatment regimens, and complications were examined versus patient age and quality of the rib graft. Distraction osteogenesis was successfully performed in six of the rib graft patients (group 1) and in all of the group 2 individuals. On the basis of the Haminishi scale, the computed tomographic scan appearance of the regenerate was classified as "standard or external" in six of the group 1 patients and as either "agenetic" or "pillar" (fibrous union) in the remaining three patients. In group 1, the average device was expanded 23 mm (range, 20 to 30 mm). Group 2 mandibular distraction results were all classified as either standard or external, and there was an average device expansion of 22.4 mm (range, 16 to 30 mm). The length of consolidation averaged 12.6 weeks in group 1, compared with 8.5 weeks in the traditional mandibular distraction patients (group 2). The mean shift of the dental midline to the contralateral side was 2.5 mm in group 1 versus 4.0 mm in group 2. Complex multiplanar and transport distractions were successfully performed on grafts of adequate bony volume. All four patients in group 1 with tracheostomies were successfully decannulated after consolidation. Rib graft distraction complications included pin tract infections in two patients, hardware failure with premature pin pullout in one patient, and evidence of fibrous nonunions in three young patients with single, diminutive rib grafts. In group 2, there were no distraction failures. Distraction osteogenesis can be successfully performed on costochondral rib grafts of the mandible; however, the complication rate is higher than in non-rib-graft patients. Performing the technique on older, more cooperative individuals seems to reduce this risk. In addition, placement of a double rib graft or an iliac bone graft of sufficient volume to create a neomandible with greater bone stock is an absolute requirement to decrease the risk of fibrous nonunion and provide a bone base of sufficient size for retention of the distraction device and manipulation of the regenerate.     

Computer planning for distraction osteogenesis

Distraction osteogenesis of the mandible has found an application in the treatment of patients with a variety of different mandibular deformities. Compared with the relatively simple unidirectional distraction of long bones as described by Ilizarov, the three-dimensional distraction of the mandible is extremely complex. Whereas experience with orthognathic surgery clearly demonstrates that careful presurgical planning is necessary to achieve predictable outcomes, there are few reported methods for the planning of mandibular distraction. The authors have developed a method for planning distraction osteogenesis of the mandible that involves the use of three-dimensional modeling and animation to simulate distraction osteogenesis in virtual reality. The first step in the authors' treatment planning process is to obtain a three-dimensional computerized scan of the facial skeleton. From this scan, a three-dimensional wire-mesh model is built using animation software. With the same software, a virtual distractor is built and installed on the wire-mesh model. The osteotomies and the distraction process are then simulated. Finally, a recipe for sequencing the linear and angular changes of the distractor is calculated. The authors have used this planning process in seven patients (age range, 4 to 10 years): four with unilateral mandibular deformities and three with bilateral. The planning process has yielded predictable and reproducible results.     

新生儿唇腭裂术前矫治方法与技术的临床探讨

目的:评价新生儿唇腭裂术前进行鼻-牙槽突-腭畸形矫治方法的疗效。方法:对28例单双侧唇腭裂新生儿进行术前鼻-牙槽突-腭畸形矫治治疗,在面部确定基点,利用数码相机拍射照片,通过image-Pro Plus5.1软件测量相关距离及角度,测量治疗前后的鼻小柱倾斜度、鼻小柱长度、鼻孔宽度和鼻孔高度。治疗前后取上颌石膏模型进行牙槽骨裂隙宽度的测量,比较矫治治疗前后腭部裂隙最大处及牙槽突裂隙的变化。结果:鼻小柱倾斜度平均减小27.11°,鼻孔宽度平均减小4.39 mm(单)或5.29 mm(双),鼻孔高度平均增加2.56 mm(单)或3.57 mm(双),牙槽突裂隙平均减少3.18 mm,腭部裂隙最大处平均减少5.77 mm。治疗前后的各项差异均有统计学意义(P0.05),鼻塌陷畸形程度也得到显著改善。结论:术前进行鼻-牙槽突-腭畸形矫治治疗可为唇腭裂患者手术治疗创造有利条件,提高其整复效果。     

本体感觉训练对膝关节周围骨折术后所致关节僵硬患者康复的影响

目的:分析本体感觉训练对膝关节周围骨折术后所致关节僵硬患者康复的影响。方法:选取我院收治的膝关节周围骨折术后所致关节僵硬患者62例,随机分成两组,对照组(n=31)采取常规康复训练,观察组(n=31)强化常规康复训练,采取本体感觉训练,比较两组康复训练方式对患者和的影响。结果:两组患者治疗前AROM水平比较(P0.05)。两组患者治疗后AROM水平均优于治疗前,且观察组高于对照组(P0.05)。两组患者治疗前LKSS评分比较(P0.05)。两组患者治疗后LKSS评分均优于治疗前,且观察组高于对照组(P0.05)。两组患者治疗前BBS评分比较(P0.05)。两组患者治疗后BBS评分均优于治疗前,且观察组高于对照组(P0.05)。结论:本体感觉训练对膝关节周围骨折术后所致关节僵硬患者康复有利,具有较高的临床价值。     

Mandibular distraction in neonates: a strategy to avoid tracheostomy

Over the past 5 years, the authors developed an application of mandibular distraction osteogenesis to eliminate existing tracheostomy. That experience led the authors to attempt mandibular distraction osteogenesis in neonates as an alternative before tracheostomy. Success with this approach using supporting objective airway measurements has been reported previously. This report includes six neonates diagnosed with Pierre Robin sequence. Of the six, five neonates ranging in age from 6 to 26 days (mean, 14.5 days) were treated by the authors with mandibular distraction over a 22-month period. The sixth neonate was treated with tracheostomy, because of other airway abnormalities. Findings included retrognathia, glossoptosis, incomplete cleft palate, and airway obstruction in each patient. Birth weights ranged from 2.8 to 3.2 kg. All patients were unable to control their airway during feeding, as evidenced by repeated episodes of choking and obstruction. Resting oxygen saturations were in the 70 to 80 percent range in all patients, with further deterioration during attempted feeding. Bronchoscopy was performed in all patients under anesthesia before distraction. Recurrent near-complete and intermittent complete airway obstruction were present in all patients at the level of the tongue base. There was a consensus by a pediatric intensivist, a pediatric anesthesiologist, and a pediatric otolaryngologist in all cases. Each patient met all criteria requiring ventilation for life support. Tracheostomy would be required if mandibular distraction osteogenesis was not performed, or if it failed. Patients with other airway abnormalities were not considered for treatment. Maxillomandibular disharmony measured at the midline ranged from 8 to 15 mm (mean, 11.2 mm). Active distraction was performed at the rate of 1 to 2 mm a day, with a consolidation period of 4 weeks. Total time of treatment was less than 6 weeks in all cases. All patients were extubated by the completion of active distraction. Distraction distance ranged from 8 to 15 mm (mean, 12.4 mm). All patients were discharged to home on apnea monitors, the use of which was discontinued after 90 days with no further apneic events. Weight gains met or exceeded the average 500 g a month after distraction. Bronchoscopy at the time of distractor removal showed correction of airway obstruction at the tongue base. Radiographs showed bilateral ossification of the distraction sites. Tracheostomy was avoided in all cases selected for treatment by distraction. Patient follow-up range was 9 to 22 months. In selected Pierre Robin sequence patients with tongue base airway obstruction, mandibular distraction osteogenesis can successfully avoid the need for and the associated mortality and morbidity of indwelling tracheostomy.     

Distraction osteogenesis: a new surgical technique for use with the multiplanar mandibular distractor

If distraction osteogenesis is to reach its full potential and achieve the level of accuracy that is possible with orthognathic surgery, its outcomes need to be as predictable. To this end, the authors developed a planning process for distraction osteogenesis similar to that used in orthognathic surgery. However, the success of the planning process depends on the authors' ability to execute the plan at the time of surgery. As a result, the authors needed to develop a surgical technique that would enable them to precisely install the distractor as indicated in the presurgical plan. The surgical technique presented in this article was developed for this purpose. The authors used this technique in seven patients (four boys and three girls; age range, 4 to 10 years). Four patients presented with unilateral deformities, and three patients presented with bilateral deformities. The follow-up period in this group of patients ranged from 12 to 33 months. The purpose of the technique is to replicate the position of the distractor on the mandible as determined by the presurgical plan. To this purpose, a custom drill guide and a surgical template have been developed. Both of these are used following the principles of triangulation to establish the pin position and orientation of the distractor. In the authors' hands, the use of this surgical technique has resulted in outcomes close to those predicted by the planning process.