颌骨畸形伴阻塞性睡眠呼吸暂停低通气综合征的牵引成骨治疗

目的　探讨牵引成骨技术在颌骨畸形继发阻塞性睡眠呼吸暂停低通气综合征(obstructivesleepapnea hypopneasyndrome,OSAHS)治疗中应用的效果。方法　收集自 1 997年 1 0月～2 0 0 2年 9月共 46例颌骨畸形伴OSAHS少年儿童 ,患者睡眠呼吸障碍经夜间多导睡眠监测证实。年龄从 4～ 1 8岁 ,平均年龄 1 1 4岁 ,其中颞下颌关节强直伴小下颌畸形 32例 ;小下颌畸形患者 9例 ;第一、二鳃弓综合征 2例 ;Crouzon综合征 3例。患者术前常规拍照、摄头颅定位侧位片 ,全景片。每位患者根据畸形情况 ,采取单侧或双侧牵引成骨治疗 ,根据侧位片预测 ,一般牵引到略微反覆盖为准。牵引幅度为 5～ 35mm ,平均牵引幅度 1 8 34mm。比较患者术前后颅颌面形态、呼吸道测量分析、多导睡眠监测结果评价治疗效果。结果　患者术后颌骨畸形明显改善 ,头影测量分析提示上呼吸道狭窄得以显著缓解 ,最小后气道径 ( x±s)由 (5 48± 2 76)mm增加到 (9 97± 2 0 5)mm ,睡眠呼吸暂停低通气指数 (apnea hypopneaindex,AHI, x±s)从术前 (66 31± 1 7 1 5)次 /s降低到 (3 1 6± 1 70 )次 /s,以上结果统计分析表明差异具有非常显著性 (P <0 0 0 1 )。结论　牵引成骨治疗颌骨畸形继发OSAHS患者具有很好的疗效     

骨保护素在兔下颌牵张后新骨组织中的表达

目的 研究骨保护素（osteoprotegerin,OPG）在不同时期下颌骨牵张成骨过程中表达水平的变化,探讨其可能发挥的作用.方法在30只成年大耳白兔的一侧下颌骨前部行骨切开术,用牵引器延长一侧下颌骨4mm,分别于牵张完成后的第1,3,7,14,28天处死一组动物,取牵引区新生骨痂行组织学及OPG免疫组化染色.结果下颌牵引延长后牵引间隙均有新骨形成,免疫组化染色OPG主要定位于成骨细胞的胞浆中.其中以牵引结束的第1,7天的表达最强,以后逐渐下降,第28天仅有微弱表达.结论OPG可能在牵引成骨过程中特别是调控组织细胞应力信号传递的早期发挥重要作用.     

采用骨内型牵张器建立垂直向牙槽骨牵张成骨动物模型

【目的】应用自行研制的骨内型牙槽骨牵张器,建立犬垂直向牙槽骨牵张成骨动物模型。【方法】实验动物为中山大学动物中心提供的健康成年杂种犬12只。实验材料为自行设计,纯钛制成的骨内型垂直向牙槽骨牵张器,体部直径3.75mm,长5mm。先拔除犬双侧下颌前磨牙,形成萎缩牙槽嵴的模型。3月后随机选取一侧行骨切开术,植入两枚牵张器。1周后开始牵张,每天1次,每次1mm,共5d;分别在牵张后1、2和3月将动物处死进行临床检查,X线检查和组织学检查。【结果】骨内型垂直牙槽骨牵张器愈合良好。牙槽骨高度平均增加(4.8±0.50)mm。组织学切片显示在牵张区有骨质形成,其骨小梁方向与牵引方向一致。【结论】采用该骨内型牙槽骨牵张器成功建立稳定的、重复性好的犬牙槽骨牵张成骨动物模型,为牙槽骨牵张器的国产化和临床上应用该项技术打下基础。     

兔下颌骨牵张成骨组织中c—los和OPG及OPGL的表达

目的：探讨在机械张力作用下骨细胞将生物力学信号转变为生物学效应的作用机理。方法：建立兔下颌骨牵张成骨模型，用免疫组化方法检测牵张中期（牵张第4天）、牵张末期（牵张第8天）与固定期2周、4周、6周的牵张区新生骨组织中c—los、骨保护素（OPG）、破骨细胞分化因子（OPGL）的分布和表达。结果：在牵张中期和末期c—los的表达为强阳性，明显强于固定期2周、4周、6周的组织。牵张中、末期和固定期2周组织OPG的表达为强阳性，在固定期4周、6周组织中逐渐减弱。OPGL仅在固定期6周组织中有较弱表达，其余各时间点均无明显阳性表达。结论：在下颌骨牵张新骨形成改建过程中，c—los与机械力刺激关系密切，OPG能促进新骨形成，而OPGL则与骨改建有关。     

Indirect decompression in spinal surgery

Indirect decompression in spinal surgery means decompression of spinal nerve tissues, such as spinal cord and nerve, without resecting the compressing tissue. Indirect spinal decompression procedures largely can be divided into segmental procedures and global spinal alignment procedures. Segmental procedures are mainly performed by the distraction between two vertebrae, which lead to the opening of the neural foramen and increases the epidural space. Such distraction can be performed through the disc space or using posterior instrumentation. Global spinal alignment procedures allow the spinal cord to migrate dorsally away from areas of anterior compression. Understanding the indirect spinal decompression procedures may broaden the options for surgical treatment and decrease the risk of spinal nerve tissue injury.     

Two-stage maxillary distraction osteogenesis using a modified external device: clinical outcome and complications

Rigid external distraction is currently used to correct severe maxillary hypoplasia. The purpose of this retrospective study was to present the clinical results and complications of a two-stage surgical approach using a modified external distraction system that consists of maxillary distraction and then maxillary fixation. We treated eight patients with cleft lip and palate in this way from 2016 to 2018. Lateral cephalograms taken before the first operation, after distraction, two weeks after the second operation, and one year after treatment were used to examine maxillofacial morphology. Velopharyngeal function was evaluated by a speech therapist. The mean movements of the maxilla forwards and downwards at Point A were 12.0 mm and 8.0 mm at the completion of distraction and those at Point B were 5.0 mm backwards and 9.7 mm downwards. Mouth opening was limited at this time, and was relieved after maxillary fixation. The mean relapse one year postoperatively was 24.3% horizontally and 52.5% vertically. Velopharyngeal function was unchanged by the operation. We conclude that the method has advantages that include the short duration of wearing distractors and increased acceptance by patients. The modified external device advanced the midface sufficiently.     

A comparison of airway interventions and gastrostomy tube placement in infants with Robin sequence

The purpose of this study was to evaluate feeding impairment following non-operative or operative management of airway obstruction in a large series of infants with Robin sequence (RS) by rate of G-tube placement. A retrospective study was conducted at Boston Children’s Hospital including 225 patients (47.1% female) with RS treated between 1976 and 2018. Subjects were grouped by intervention required for successful management of airway obstruction: non-operative only (n = 120), tongue–lip adhesion (TLA, n = 75), mandibular distraction osteogenesis (MDO, n = 21), or tracheostomy (n = 9). The operative group had a higher rate of G-tube placement (58.1%) than the non-operative group (28.3%, P < 0.0001). Subjects in the TLA and tracheostomy groups had higher odds of G-tube placement than subjects in the MDO group: odds ratio (OR) 5.5 (95% confidence interval (CI) 1.8–17.3, P = 0.004) and OR 27.0 (95% CI 3.2–293.4, P = 0.007), respectively. Syndromic patients and those with gastrointestinal anomalies also had higher odds of G-tube placement: OR 3.5 (95% CI 1.7–7.2, P = 0.001) and OR 5.9 (95% CI 1.6–21.0, P = 0.007), respectively. Infants with RS who require an airway operation and those with a syndromic diagnosis or gastrointestinal anomalies are more likely to require placement of a G-tube. Of the operative groups, MDO was associated with the lowest G-tube rate, compared to TLA and tracheostomy.     

The accuracy of virtual-surgical-planning-assisted treatment of hemifacial microsomia in adult patients: distraction osteogenesis vs. orthognathic surgery

Hemifacial microsomia (HFM) is a common congenital craniofacial deformity with a high prevalence. Orthognathic surgery and distraction osteogenesis are two conventionally used treatments of HFM. The main objective of this retrospective study was to evaluate the accuracy of two treatments with the help of virtual surgical planning in adult HFM patients. Sixty-eight adult patients with unilateral HFM were enrolled in this study. Preoperative surgical planning and simulation were performed on three-dimensional computed tomography models. Orthognathic surgery or distraction osteogenesis was performed under the guidance of three-dimensional surgical templates. Postoperative evaluation of the intervention was performed by comparison of the affected ramus height, chin deviation and the occlusal cant in surgical planning and actual result. Outcome and feedback information (an average of 14 months) showed that virtual surgical planning was accurately transferred to actual surgery in both surgical approaches. There were no statistical differences between the accuracy of affected ramus height and the occlusal cant in two surgical approaches. The orthognathic group showed significantly higher accuracy in chin deviation. In conclusion, virtual surgical planning and three-dimensional surgical templates were proved to facilitate treatment planning and offer an accurate surgical result in the treatment of adult HFM patients.