牵张成骨和正颌外科治疗火器伤性颌面部缺损和畸形

目的:探讨牵张成骨和正颌外科技术治疗火器伤性牙颌面畸形的临床应用。方法:1例患者因火器伤严重颌面部畸形,主要表现为右侧升支高度严重不足、咬合关系错乱和上颌牙弓缩窄。手术采用牵张成骨技术,分两次牵张,恢复右侧升支高度。继而采用正颌外科方法矫正咬合关系。结果:患者均顺利完成治疗,一期牵张成骨骨延长约10mm,二期延长约15mm,右侧下颌升支高度基本恢复,正颌外科术后,患者面型得到明显改善,咬合关系恢复,对治疗效果满意。结论:颌面部火器伤会导致严重的软组织瘢痕,骨再生能力降低,造成的畸形复杂,不规则。在应用牵张成骨和正颌外科治疗火器伤性牙颌面畸形必须要遵从其基本原理,同时要兼顾火器伤牙颌面畸形的临床特点,进行个性化设计,最终可以得到良好的治疗效果。     

Le Fort Ⅰ型截骨术在唇腭裂正颌外科中的应用与评价

目的:观察分析Le Fort Ⅰ型截骨术在唇腭裂正颌外科中的应用效果.方法:回顾2004年3月至2006年12月武汉大学口腔医学院口腔颌面外科收治的唇腭裂患者的临床资料,并进行总结与分析,所有患者均进行了以Le Fort Ⅰ型截骨术为主的正颌外科治疗.结果:共收集相关病例16例,其中男9例,女7例,平均年龄22.4岁.术前∠SNA平均73.2°,术后LSNA平均79.5°;上颌前移距离平均8.13mm.平均随访时间7.3个月.所有患者术后面容改善明显,经正畸治疗后咬合关系满意.结论:以Le Fort Ⅰ型截骨术为主的正颌外科治疗,可以显著改善唇腭裂患者的颌骨与面容畸形.     

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牙颌面畸形正颌外科治疗需要根据畸形的情况、治疗的要求以及术前患者的生理、心理状态评估综合制定治疗方案.在术前必须对治疗方案、(牙合)关系的调整、骨切开的部位、骨段移动的方向和距离经过精确的设计.正颌外科的术前设计包括头影描迹设计、预测,计算机辅助设计以及模型外科等.本文结合笔者的临床经验和国内外文献对牙颌面畸形正颌外科治疗的术前设计进行述评,强调了牙颌面畸形正颌外科手术方案的设计原则,提出了计算机辅助外科在正颌外科领域具有显著的优势和广阔的应用前景.     

正颌外科及其新进展

正颌外科是口腔颌面外科的一门新兴学科,是治疗骨性牙颌面畸形最根本、最有效的手段.随着正颌外科技术及理念的进一步推广,它的临床应用范围越来越广泛,特别是牵张成骨技术在口腔颌面外科的成功应用,为许多严重牙颌面畸形的治疗提供了新的方法和途径.     

下颌外科矫正牙颌面畸形300例总结

为总结正颌外科矫正牙颌面畸形的临床经验。方法对３００例牙颌面畸变形患者进行了正颌外科手术，其中１８０例上颌前突和上颌前部发育不足畸形，行上下颌前部根尖下戴骨术；４０例上下颌后牙正反锁ＨＥ，了段性根尖下戴骨术。     

天然型无机骨骨膜下植入的实验研究

目的 观察天然型无机骨骨缺损内与骨膜下植入后在成骨能力,愈合过程上的差异。方法 将块状天然型无机骨植入兔下颌骨缺损内与骨膜下（骨皮质表面）,进行光镜及扫描电镜观察。结果 骨缺损组植入４周即有新骨向无机骨孔内长入,１２周无机骨少部分被吸收,新骨与无机骨间界面清晰,骨缺损被新骨完全修复。骨膜下组８周出现少量新骨,１２周大部分无机骨被纤维结缔组织包裹,与原骨床间主要为纤维性间隔,仅少部分与新骨组织结合。     

牵张成骨联合正颌正畸治疗成人严重小下颌畸形

目的：探讨牵引成骨技术联合正颌正畸治疗重度小下颌伴偏颌畸形患者下颌骨严重发育不足及咬合关系紊乱的疗效。方法：对2例继发于儿童时期颞下颌关节损伤的小下颌伴偏颌畸形患者采用牵张成骨技术进行治疗。手术行双侧下颌角处截骨,安置牵引器,延长下颌升支及下颌体。第二期在拆除牵引器后进行正畸治疗,继而采用正颌外科方法进一步矫正颌面畸形及咬合关系,术后正畸治疗矫正咬合关系,排齐牙列。结果：2例患者均顺利完成治疗。下颌骨最小牵引距离25 mm,最大牵引距离30 mm,牵引区成骨良好,SNB角由术前平均67°增加到术后80°,小下颌及偏颌畸形得以矫治。联合正颌外科及正畸治疗后,面形及咬合功能均获得满意效果。术后经过2年6个月随访,未见复发。结论：联合应用牵张成骨和正颌外科技术并配合正畸治疗是矫治成人重度小下颌不对称性牙颌面畸形的有效治疗方案。     

98例唇腭裂患者牙颌面畸形的正畸-正颌外科联合治疗分析

目的 评价正畸-正颌外科联合治疗唇腭裂伴牙颌畸形的效果。方法 回顾分析1990年1月-2000年6月期间在上海第二医科大学和香港大学口腔颌面外科收治的98例唇腭裂伴牙颌面畸形患者，男性52例，女性46例，年龄16—40岁，平均年龄20．5岁。所有患者均在手术前完成正畸治疗，排齐牙列，关闭间隙等。上颌骨手术采用标准化截骨前移手术，伴牙槽裂的患者同期行髂骨取骨植骨术。手术方法包括：①牙槽裂已植骨修复者。采用标准Le fortⅠ型截骨前移术；②牙槽裂未植骨修复的单侧腭裂患者，采用改良上颌骨截骨手术，即非裂侧用Le Fort Ⅰ型截骨术,裂隙侧采用牙槽骨截骨手术(Schuchardt法)，同期行牙槽裂植骨术；③牙槽裂未植骨修复的双侧腭裂患者，采用前颌骨截骨手术(Wunderer法)和双侧上颌骨后份牙槽骨截骨手术(Schuchardt法)，同期行牙槽裂植骨修复术。骨间采用小钛板坚强内固定。随访时间1／2—5a。平均2．6a。结果 术后患者的面型均取得了明显的改善，面部比例协调，咬合关系相对稳定。结论 正畸-正颌外科联合治疗唇腭裂伴牙颌面畸形的效果稳定，应该作为这类畸形治疗的常规方法。     

双颌畸形的正颌外科矫治

复杂双颌畸形的治疗是正颌外科治疗的难点. 近年来正颌外科手术、正畸技术的成熟与发展,特别是数字化外科在正颌领域的成功应用,为复杂牙颌面畸形的诊断、治疗提供了更为精确的处理手段,使得患者的治疗效果日趋完善. 广东省口腔医院口腔颌面外科每年收治100多例复杂的双颌畸形患者,对双颌畸形的正颌外科矫治积累了较为丰富的经验. 本文就双颌畸形正颌外科矫治的有关问题进行阐述.     

人格评估法在正颌外科中的应用

牙颌面畸形患者的心理因素是其决定选择正颌手术治疗及术后效果的重要因素之一,甚至是首要因素。列举部分在正颌外科中常用的心理测量量表,尤其是人格评估量表。分析国内外心理测量在正颌外科中的研究现状．运用医学心理学知识对牙颌面畸形患者心理问题进行分析,研究患者在正颌手术治疗前后的心理变化,从而达到提高治疗效果和术后满意度的目的。     

Autogenous masticatory mucosal grafts in extraction socket seal procedures: a comparison between sockets grafted with demineralized freeze‐dried bone and deproteinized bovine bone mineral

Successful preservation of the edentulous ridge after extractions may eliminate or reduce the need for ridge augmentation procedures. It has been claimed that grafting fresh extraction sockets and sealing them with autogenous soft tissue grafts promote ridge preservation after tooth extraction. In this study, the survival of free autogenous connective tissue grafts sealing extraction sites was evaluated. In 24 healthy patients, 42 maxillary anterior teeth were extracted. After socket debridement, soft tissue margins of the socket orifice were carefully cut to remove epithelial debris, Sockets were filled with either demineralized freeze-dried bone allografts (DFDBA) or deproteinized natural bovine bone mineral xenograft (DBBMX) to the level of the alveolar bone crest. Circular connective tissue grafts, slightly larger in diameter than the soft tissue socket orifice, were obtained and placed on top of the filler graft material sealing the sockets. Grafts were stabilized and secured by sutures and inspected weekly for the first month. The grafts were classified into 3 groups according to clinical parameters: vital, partially vital and non-vital. After 1 week, 18 grafts were vital, 13 partially vital and 11 non-vital. When only 1 sample unit (1 site per patient) was compared between DFDBA and DBBMX grafted sockets, no significant difference in graft vitality was shown (P = 0.34 for vital; P = 0.67 for vital plus partially vital). After 1 month, all socket orifices were sealed with mucosa. Based on the present observations, it seems that connective tissue grafts sealing fresh extraction sites are mainly dependent on underlying tissue vascularization and that sealing grafted fresh extraction sockets filled with bone substitute allograft or xenograft materials may be beneficial but an unpredictable procedure.     

Coralline porous hydroxylapatite as a bone graft substitute in orthognathic surgery

This prospective study was undertaken to evaluate the use of coralline porous hydroxylapatite as a bone graft substitute in orthognathic surgery. Ninety-two consecutive patients received a total of 355 block implants to the maxilla (294), mandible (41), and midface (20). There were 202 implants positioned directly adjacent to the maxillary sinus. Complications were minimal, the most common being exposure of the implant to the oral or nasal cavity. Histologic evaluation of implants that were biopsied in nine patients, four to 16 months postsurgery, revealed connective tissue ingrowth throughout the implants with approximately one-third being bone of variable maturity and two-thirds being soft tissue.     

Alveolar ridge augmentation using nonresorbable hydroxylapatite with or without autogenous cancellous bone

A four-year prospective evaluation of the use of nonresorbable, particulate hydroxylapatite (HA) to augment deficient alveolar ridges was performed. The material was used alone and in combination with finely crushed autogenous cancellous bone. Implants were delivered subperiosteally by syringe injection, usually using local anesthesia for Class I to Class III ridges and general anesthesia for Class III and Class IV ridges. The improved ridge height and width were stable. Postoperative resorption with significant loss of ridge height, frequently seen with rib and iliac crest onlayed grafts, was not observed with HA augmentation. Permanent denture construction began as early as three weeks postoperatively and by four to six weeks if HA was combined with autogenous cancellous bone. It was possible to place mandibular staple implants simultaneously or following HA augmentation. Visor osteotomy techniques were improved by use of HA to produce a wider, more convex stable ridge. Although skin, mucosa, or dermal vestibuloplasties were performed as early as three months postoperatively in a small number of patients, there appeared to be a lesser need for vestibuloplasty after HA augmentation than after onlay bone grafting. In addition, prosthodontists performed fewer denture relines after HA augmentation than after onlay bone grafts. The authors believe the most significant factor accounting for these observations is the firm, nonmobile mucosal base resulting from augmentation with HA. The resultant stable, soft tissue base and improved ridge height and contour have contributed to a comfortable, retentive, stable denture for these patients. The prosthetic and surgical procedures are easier to perform and have produced superior, more permanent results than onlay bone grafts and alloplasts. Preliminary studies also point to exciting possibilities for use of HA as a bone substitute/marrow extender in maxillary and mandibular defects, cysts, and clefts and in osteotomies for orthognathic surgery.     

计算机辅助正颌外科模拟和预测系统的准确性评估

目的分析和评价计算机辅助正颌外科模拟和预测系统(CASSOS 2001)的准确性。方法将25例颌面畸形患者术前X线侧位定位片及彩色软组织侧面照输入CASSOS 2001系统进行头影测量分析,并通过骨段移动来模拟正颌手术,预测术后咬合关系及软组织侧貌;再将术后X线侧位定位片输入该系统进行头影测量分析,选取10项测量参数,将术后实际结果和术前预测结果进行配对t检验。结果硬组织相关的4个测量项目(SNA角、SNB角、ANB角、MP-SN角),其术前模拟结果和术后真实结果比较均无统计学意义(P>0.05)。软组织相关的6个测量项目中,仅上唇长一项有统计学意义(P<0.05),其余5项包括Sn(鼻下点)到零子午线的距离、Pog'(软组织颏前点)到零子午线的距离、面突度、鼻唇角及唇颏比均无统计学意义(P>0.05)。此外,软组织相关项目的均差及标准差普遍大于硬组织相关项目。结论 CASSOS 2001系统对于正颌术后硬组织变化的预测是准确的,对软组织变化的预测略有不足,尤其是唇部。标志点的定位误差,软硬组织移动比例的差异等均会对预测结果产生影响,因而CASSOS 2001系统尚有较大的改善空间。     

Porous block hydroxyapatite in orthognathic surgery.

Seventy-six nonconsecutive patients undergoing orthognathic surgery, in whom blocks of porous hydroxyapatite were implanted into osteotomy gaps in lieu of autogenous bone grafts, are the subjects of this report. Surgical procedures include inferior maxillary repositioning (10 patients), maxillary advancement (24 patients), transverse maxillary expansions (17 patients) and inferior repositioning of the chin (25 patients). A total of 140 anatomic sites were implanted. Eleven patients later consented to open biopsy of the implant material at a mean 10.2 months following implantation. At the time of follow-up, mean 16.3 months, excellent osseous stability was observed. Three patients developed complications relative to the presence of the implant. Twenty-one of 24 biopsy specimens demonstrated an osseous union of implant to bone with osseous deposition within the implant pores. Radiographic follow-up revealed implant blocks to maintain their volume with no change in density or discreteness. The biological behavior and biomechanical properties of porous block hydroxyapatite are discussed. These implant characteristics make it a feasible bone graft substitute in orthognathic surgery and justify its continued use in this context.     

Soft tissue response in orthognathic surgery patients treated by bimaxillary osteotomy: cephalometry compared with 2-D photogrammetry

Purpose

Since improvement of facial aesthetics after orthognathic surgery moves increasingly into the focus of patients, prediction of soft tissue response to hard tissue movement becomes essential for planning. The aim of this study was to assess the facial soft tissue response in skeletal class II and III patients undergoing orthognathic surgery and to compare the potentials of cephalometry and two-dimensional (2-D) photogrammetry for predicting soft tissue changes.

Material and methods

Twenty-eight patients with class II relationship and 33 with class III underwent bimaxillary surgery. All subjects had available both a traced lateral cephalogram and a traced lateral photogram taken pre- and postsurgery in natural head position (median follow-up, 9.4?±?0.6 months).

Results

Facial convexity and lower lip length were highly correlated with hard tissue movements cephalometrically in class III patients and 2-D photogrammetrically in both classes. In comparison, cephalometric correlations for class II patients were weak. Correlations of hard and soft tissue movements between pre- and postoperative corresponding landmarks in horizontal and vertical planes were significant for cephalometry and 2-D photogrammetry. No significant difference was found between cephalometry and 2-D photogrammetry with respect to soft to hard tissue movement ratios.

Conclusions

This study revealed that cephalometry is still a feasible standard for evaluating and predicting outcomes in routine orthognathic surgery cases. Accuracy could be enhanced with 2-D photogrammetry, especially in class II patients.     

Soft tissue response and facial symmetry after orthognathic surgery

ObjectiveIn orthognathic surgery aesthetic issues and facial symmetry are vital parameters in surgical planning. Aim of this investigation was to document and analyze the results of orthognathic surgery on the base of a three-dimensional photogrammetric assessment, to assess the soft tissue response related to the skeletal shift and the alterations in facial symmetry after orthognathic surgery.Patients and methodsIn this prospective clinical trial from January 2010 to June 2011, 104 patients were examined who underwent orthognathic surgery due to mono- or bimaxillary dysgnathia. The standardized measurements, based on optical 3D face scans, took place one day before orthognathic surgery (T1) and one day before removal of osteosynthesis material (T2).ResultsSoft tissue changes after procedures involving the mandible showed significant positive correlations and strong soft tissue response (p < 0.05). The midfacial soft tissue response after maxillary advancement was only of minor extent (p > 0.05). The facial surfaces became more symmetric and harmonic with the exception of surgical maxillary expansion, but improvement of facial symmetry revealed no statistical significance.ConclusionSoft tissue response after orthognathic surgery and symmetry are only partially predictable, especially in the maxillary and midfacial region. Computer programs predicting soft tissue changes are not currently safely reliable and should not be used or with caution to demonstrate a patient potential outcome of surgery.     

Frozen femoral head allogeneic bone grafts for orthognathic surgery

Bone grafts are occasionally required in orthognathic surgery procedures. Allogeneic grafts are desirable because they decrease patient morbidity. Fresh frozen bone obtained during total hip replacement has been used in 12 orthognathic operations. Observations for one to three years have showed very good results.     

Use of distraction osteogenesis in orthognathic surgery

Distraction osteogenesis (DO) is a surgical technique that takes advantage of natural wound healing mechanisms to augment bone and soft tissues. DO is extremely versatile and can be applied to nearly any bone. In the craniofacial skeleton, the cranial vault, midface, maxilla and mandible are the most common sites for DO. This technique allows larger skeletal movements than could be achieved with conventional techniques, decreases operative time and blood loss, eliminates the need for bone grafts and associated donor site morbidity, and may improve postoperative stability. DO can be used in preparation for, in lieu of, or in combination with orthognathic surgery to correct dentofacial deformities. DO requires meticulous planning to achieve optimal results.     

正颌外科手术的计算机辅助模拟以及预测的准确性评价

目的：计算机辅助模拟正颌外科手术术后软硬组织侧貌,分析术前预测值与术后实际值之间的差异。方法：选取预进行正颌外科手术的牙颌面畸形患者术前去代偿后的侧貌照片和头颅侧位定位片输入Winceph 8.0系统进行头影测量分析,并通过骨段移动来模拟正颌手术,预测术后软硬组织侧貌。将术后6个月以上的头颅侧位定位片输入Winceph 8.0系统进行头影测量分析,选取19项测量参数,将术前预测值和术后实际值进行配对t检验,并评价患者性别以及骨段移动距离对预测结果的影响,评价该预测系统的准确性。结果：硬组织相关的11个测量项目,其术前模拟值和术后实际值间比较均无统计学意义。软组织相关的8个测量项目术前模拟值和术后实际值间比较,仅上唇长有统计学意义（P〈0.05）,其余测量项目均无统计学意义。不同性别的测量结果比较,差异无统计学意义。下颌骨段水平向移动大于8mm组和4-6mm组、6-8mm组相比,上唇长有统计学意义（P〈0.05）。下颌骨段垂直向移动-2-0mm、0-2mm和2-4mm相比,差异无统计学意义。上颌骨段水平向移动2-4mm组与4-6mm组之间,以及垂直向移动-2-0mm与0-2mm之间相比,差异无统计学意义。结论：Winceph8.0系统对正颌手术术后硬组织侧貌的预测准确,对软组织的预测稍显不足,尤其是上唇长。预测结果不受性别影响。下颌骨段后退大于8mm的患者,上唇长的预测准确性较低。