犬同种异体下颌区复合器官移植后排斥反应的组织学特征

目的本研究探讨了犬下颌区复合器官移植后排斥反应的组织学特征。方法通过光镜和电镜观察，同种异体下颌区复合器官移植后早期不同器官和组织的组织学变化。结果发现同种异体下颌复合器官移植后不同组织的排斥反应过程是不同的，皮肤、粘膜、肌肉和血管是抗原性较强的组织，皮肤排斥反应过程最为严重且难以控制，肌肉显示出严重的退行性改变和明显的血管炎。牙髓均呈纤维化改变、网状变性或坏死，牙周的反应不十分强烈。长期存活者各个组织如皮肤、肌肉和血管均表现出接近正常的组织学形态。结论如果组织配型和免疫抑制药物得到改善，在将来下颌复合器官的移植的临床应用是完全可能的。感染是移植后局部严重的并发症，其可加重排斥反应对组织的破坏。     

同种异体冻干下颌骨移植修复下颌骨缺损的临床应用

目的：探讨同种异体冻干下颌骨移植修复下颌骨缺损的可行性，并讨论其抗原性、生物力学特性、骨愈合机制及优缺点。方法：对进行同种异体冻干下颌骨移植修复下颌骨大节段肿瘤切除后缺损和颞下颌关节移植置换的7例患者进行随访研究，根据临床检查及X线片对手术效果进行评估。结果：手术切口均一期愈合，未发生排斥反应及骨折现象，移植骨愈合良好，外形及功能恢复满意。结论：同种异体冻干下颌骨移植是修复下颌骨大节段肿瘤性缺损和颞下颌关节移植置换的可行方法。     

下颌复合组织移植实验的显微外科解剖学基础研究

同种异体下颌区复合器官和组织移植的研究刚刚起步,为了了解下颌区复合器官和组织移植的显微外科解剖基础,在犬、兔和猴进行了下颌区及颈部血管解剖比较研究。结果发现,在下颌区域,颌外动脉、颌内动脉、颌外静脉和颌内静脉形成闭合的循环回路。在此基础上可以确定下颌复合器官移植的范围并使移植手术得以进行。     

肿瘤坏死因子α和白细胞介素2在大鼠皮肤移植中的作用

目的：探讨肿瘤坏死因子α(TNF-α)和白细胞介素2(IL-2)在同种异体大鼠皮肤移植后免疫排斥反应中的作用，研究组织工程皮肤的组织相容性。方法：取SD大鼠皮肤和实验室培养的组织工程SD大鼠皮肤移植于成年Wistar大鼠，移植成功后取不同时间点标本用免疫组织化学方法和Western blot方法检测TNF-α和IL-2在组织中的表达。结果同种异体皮肤移植组，TNF-α和IL-2有显著表达；组织工程皮肤移植后，局部组织中TNF-α和IL-2水平显著低于同种异体皮肤移植组。结论：TNF-α和IL-2水平的改变与同种异体皮肤移植后免疫排斥反应的发生密切相关，组织工程皮肤只具有很弱的免疫原性，不引起显著的排斥反应。     

大块同种异体骨移植重建下颌骨失败原因分析

目的探讨大块同种异体骨移植重建下颌骨缺损临床失败的原因。方法对深冻辐射灭菌大块同种异体下颌骨置换26例大块下颌骨缺损术中5例(19．23％)临床失败患者的追踪观察，就患者的全身情况、同种异体骨免疫原性、骨块内固定的稳定性、伤口的严密缝合程度和感染情况等影响同种异体骨移植愈合的相关因素以及骨愈合的X线片进行临床分析。结果术后追踪1～12个月，失败的5例同种异体大块下颌移植因术后排斥或感染5例，内固定松脱3例，X线平片见宿主骨与移植骨不愈合，需手术取出。结论内固定松脱、术后排斥或晚期感染是深冻辐照大块同种异体下颌骨移植重建下颌骨缺损临床失败的主要原因。     

口腔颌面部复合组织缺损与同种异体复合组织移植

口腔颌面部大型复合组织缺损及其整复历来是人们关注的问题，本文综述了大型复合组织缺损的特点及自体组织移植的应用和不足，以及同种异体复合组织移植的研究进展。     

同种异体舌移植的研究进展

先天或后天原因所致舌严重畸形、缺损或缺失是口腔颌面外科临床中常见问题。目前常规方法修复存在很多问题,效果尚不能令人满意。学者们逐渐将目光转向同种异体舌移植。本文就舌同种异体移植外科技术方面及抑制免疫排斥反应等方面的研究进展作一综述。     

犬下颌复合器官同种异体移植模型的建立

为建立同种异体下颌区复合器官移植的动物实验模型，分别选用家兔和杂种犬行下颌复合器官同种异体原位移植术５例和１４例，手术成功率分别为零和９３％。手术成功的关键在于选择耐受力强的动物、术中减少出血及缩短手术时间和采取有力的抗感染措施。     

犬半舌同种异体移植动物模型的建立

目的：建立犬半舌同种异体移植模型,探讨舌同种异体移植的可行性。方法：选用8只Beagle犬分别作为供/受体,随机配成4对。供/受体同时进行吻合血管神经的右侧半舌交换移植手术。配对犬随机分为2组,对照组不用免疫抑制剂（A组）,实验组使用免疫抑制剂（B组）。术后观察移植半舌的大体情况,对存活100d动物的舌下神经进行电生理检测。结果：A组动物均发生急性排斥反应。B组动物中,1只出现不可逆转的排斥反应,2只动物因颈部感染死亡,1只术后存活100d,移植物完全成活,电生理实验发现舌下神经传导功能部分恢复。结论：采用非同胞Beagle犬进行半舌同种异体移植是可行的。先使用环孢素大剂量冲击再小剂量维持,可以获得较好的抗排斥效果。     

同种异体肋软骨膜游离移植颞下颌关节重建的实验研究

目的 本研究首次提出了同种异体游离肋软骨膜（ＰＣ）移植再生关节软骨的新方法。方法 通过分阶段取材分析，动态观察、分析了同种异体ＰＣ再生软骨的情况。结果 同种异体移植的ＰＣ可以再生软骨，而且再生的软骨与异体移植的软骨一样可以长期存活，而未引起明显的急性、慢性及超急排斥反应。结论游离移植的ＰＣ形成的关节软骨比其它一些方法形成的假关节有较多的生理功能，属于关节的生物性修复。     

复合树脂充填不同角度楔形缺损效果的三维有限元分析

目的:研究复合树脂对下颌第一前磨牙4种角度楔形缺损的修复效果。方法:在前期建立的深1 mm,夹角分别为30°、60°、90°、120°的下颌第一前磨牙颊颈部楔形缺损有限元模型上,通过赋予牙本质参数和复合树脂参数,获得模拟复合树脂充填修复模型、模拟完整牙体实验模型和未修复的楔形缺损模型,分别经100 N轴向加载后,利用三维有限元分析法进行应力分析。结果:由牙本质充填模拟的完整牙体其应力分布状况与复合树脂充填体相似,均为近中侧高于远中侧,各种角度楔缺的Von Mises应力集中点均位于修复体外表面近中侧边缘;复合树脂修复体部分的Von Mises应力最大值低于模拟牙本质修复体。30°楔缺时树脂修复模型在平面O上承受较大应力的范围略大于完整牙体;在60°楔缺时树脂修复模型在平面O上承受较大应力的范围略小于完整牙体;在90°和120°楔缺时树脂修复模型在平面O上承受较大应力的范围明显小于完整牙体。30°、60°、90°、和120°4种楔形缺损角度情况下,树脂修复组和完整牙体组在直线L上的Von Mises应力分布接近(P>0.05),均明显小于未充填的楔缺模型(P<0.05)。结论:复合树脂充填对于4种夹角角度的楔形缺损均具有保护作用,可使患牙内部的应力分布情况恢复正常,更好的阻断了牙体内部的应力集中现象。     

游离腓骨肌-皮-筋膜复合瓣同期修复40例放射性下颌骨坏死术后缺损效果评价

目的： 探讨游离腓骨肌-皮-筋膜复合瓣在修复下颌骨放射性骨坏死（osteoradionecrosis of the jaws,ORNJ）术后软、硬组织缺损的应用价值。方法： 选择2014年3月—2017年7月间,中山大学孙逸仙纪念医院口腔颌面外科40例下颌骨 ORNJ患者,所有病例原发肿瘤均为鼻咽癌,排除鼻咽癌复发。以游离腓骨肌-皮-筋膜复合瓣重建放射性下颌骨坏死手术切除后的骨缺损,以皮岛修复皮肤软组织缺损,以筋膜修复口内黏膜缺损并充填软组织缺损的空腔,记录腓骨截骨、组织瓣存活情况,供区、受区并发症,术后开口度和余留牙咬合情况,对颌面部外形和功能进行评价。结果： 随访3～6个月,游离腓骨肌-皮-筋膜复合瓣重建下颌骨缺损均获成功。下颌骨截骨长度5.5～16.0 cm,切取腓骨长度7.5～17.0 cm。无1例发生严重供区或受区并发症,所有病例外形恢复良好,开口度1.0～3.5 cm,余留牙咬合正常。结论： 游离腓骨肌-皮-筋膜复合瓣能很好地即刻重建放射性下颌骨坏死术后颌面部软、硬组织缺损,降低手术并发症,值得临床推广应用。     

石家庄地区正畸患者恒牙先天缺失的调查分析

目的调查分析石家庄地区正畸患者恒牙先天缺失的发病率及特征。方法对河北医科大学口腔医院正畸科2010~2012年正畸患者中3274名有效病例的病历资料进行回顾分析。通过观察其全颌曲面断层片,分析恒牙先天缺失的发病率及分布差异。结果除第三磨牙外恒牙先天缺失的发病率为9.13,性别间差异无统计学意义（P〉0.05）。个别缺牙例数（缺牙数〈6）占总缺牙例数的95,其中缺失1~2颗牙的例数占总缺牙例数的88.6;多数缺牙例数（缺牙数≥6）占总缺牙例数的5。前、后牙区的缺牙发病情况在缺失1~2颗牙时,主要发生在前牙区,缺失2颗以上时,后牙区的缺失发病率高于前牙区（P〈0.05）;下颌缺牙发病率高于上颌（P〈0.05）。缺牙频率最高的是下颌侧切牙（25.3）,其次是下颌第二前磨牙（18.3）。结论石家庄地区正畸患者恒牙先天缺失（不包括第三磨牙）发病率为9.13,。其中以缺失1~2颗牙最常见,恒牙先天缺失更多的发生在前牙区及下颌,最常见的缺失牙位是下颌侧切牙和下颌第二前磨牙。     

第三磨牙伸长对下颌各牙根尖应力分布规律影响的光弹实验研究

目的 :探讨单侧上颌或下颌第三磨牙伸长对下颌各牙根尖应力传导规律的影响。方法 :采用透明环氧树脂复制以相同牙列而排成的正常牙合、单侧上颌或下颌第三磨牙伸长的咬合模型各 1副 ,2 .0kg垂直加载 ,切片后投影式光弹仪上观测各牙根尖主应力的大小与方向 ,及其与下颌牙根轴倾角间的关系。结果 :所建 3个 (种 )模型下颌牙根轴倾角无显著差异 ,上颌第三磨牙伸长对侧及下颌第三磨牙伸长侧磨牙的根尖主应力较正常牙合者更偏向远中颊侧 ,应力水平显著升高 (P <0 .0 5 )。而相应另一侧的磨牙根尖主应力方向更偏向近中舌侧。上颌第三磨牙伸长对侧及下颌第三磨牙伸长侧的应力水平均高于正常牙合 (P <0 .0 5 )。结论 :单侧第三磨牙伸长可致牙根尖应力发生改变。     

An orthopantomographic study of hypodontia in permanent teeth of Japanese pediatric patients

Hypodontia of permanent teeth was evaluated from orthopantomograms of 2072 apparently healthy pediatric patients at The Hospital of Nihon University School of Dentistry at Matsudo. The prevalence of congenitally missing teeth (CMT) was 8.7% in boys and 10.8% in girls, and 9.4% for both sexes combined. Most cases (67.8%) involved either one or two missing teeth. There were in total 574 CMT, and on average 2.8 teeth were missing per child. The most commonly absent tooth was the mandibular second premolar. On the other hand, no first molars were missing in any case. A high frequency of CMT mandibular incisors (18.82%) was observed, and this seems to be a characteristic peculiar to individuals of Asian ethnicity. Oligodontia (6 or more CMT excluding the third molar) ranged from 6 to 14 teeth, with a prevalence of 1.4% in general: 1.8% for girls and 0.9% for boys. Symmetry of CMT was predominant: 214 pairs for bilateral symmetry and 107 pairs for symmetry between two antagonistic quadrants. The distribution of CMT between maxillary and mandibular hypodontia in the right and left quadrants for boys and girls no had significant association (P < 0.05).     

Nervus lingualis: applied anatomical relevance to dental practice and oral surgery.

N. lingualis supplies general sensory branches to the mucosa of the anterior two-thirds of the tongue, sublingual mucosa and the mandibular lingual gingiva. From an oral surgery point of view, the course of the lingual nerve is critical due to the intimate medial relationship to the roots of the mandibular third molar. "Hitch-hiking" special sensory taste fibres from the chorda tympani (cranial nerve seven) are distributed to the mucosa of most of the anterior two-thirds of the tongue, together with the general sensory branches derived from the mandibular division of the trigeminal nerve. The circumvallate papilLae anterior to the sulcus terminalis are supplied by special sensory fibres (taste) of the glossopharyngeal nerve, latrogenic lingual nerve injury, subsequent to mandibular wisdom teeth removal, can result in irreversible gustatory deficits and somatosensory dysfunction. Patients undergoing oral surgery for impacted mandibular molars should be informed of the anatomical relationship of the lingual nerve to the roots, and the implications of denervation.     

Distribution of developmental defects of tooth enamel by tooth-type in 11–12-year-old children in South Wales

The distribution of enamel developmental defects in 759 11-12-yr-old children from South Wales is described. Overall, 8% of maxillary teeth were affected compared to 3.6% of mandibular teeth. Most teeth were affected equally on right and left sides of the mouth except for maxillary lateral incisors, which had significantly more defects on the right (P less than 0.05) and maxillary first molars, which had significantly more defects on the left (P less than 0.025). Maxillary central incisors (18.7%) were affected by enamel defects most often followed by maxillary first molars (8.1%) and maxillary lateral incisors (7.2%). The ranking order of the teeth varied when the prevalence of the different types of defects was assessed. White demarcated opacities were seen most often in maxillary central incisors (10.8%), yellow demarcated opacities in maxillary first molars (1.8%), diffuse opacities in maxillary central incisors (6.6%) and hypoplasias in mandibular first premolars (1.5%). Defects of all types occurred most frequently on the buccal surfaces of the teeth. In premolar and molar teeth more defects occurred on the occlusal surface than on the lingual.     

Tooth transplantation with the periodontium intact: a histometric analysis

A method was devised, from a pilot study, for transplanting a root-treated tooth with an intact periodontium into a newly prepared socket to assess whether the prognosis for transplantation procedures could be improved. Five male vervet monkeys were used for the definitive study. The mandibular central incisors were extracted from each monkey and the sockets were allowed to heal for 5 weeks. Thereafter a window of gingiva overlying each of these healed receptor sites was removed and the sockets were prepared with tapered burs. The distal root of the mandibular second molar was used as the transplant tooth and the distal root of the first molar as the control tooth. The transplant tooth was removed, together with surrounding alveolar bone which was then trimmed to a thickness of approximately 1 mm. The control tooth was extracted with root forceps. After transplantation, the teeth were splinted to the adjacent incisors for 3 weeks. After 8 weeks the healing process was examined histologically, both qualitatively and quantitatively. Replacement resorption (ankylosis) was not observed. Student's t test for paired samples revealed that the incidence of secondary cementum formation was significantly greater on the control teeth. The minimization of trauma may be the reason ankylosis did not occur.