Heterotopic ischemic pain attenuates somatosensory evoked potentials induced by electrical tooth stimulation: diffuse noxious inhibitory controls in the trigeminal nerve territory.

The purpose of this study was to determine whether the late component of somatosensory evoked potentials (SEP) induced by electrical tooth stimulation and pain intensity are inhibited by heterotopic ischemic stimulation. The tourniquet pressure with 50 mmHg greater than the individual's systolic pressure was applied to the left upper arm for 10 min as ischemic conditioning stimulation. The late component of SEP and visual analogue scale (VAS) were recorded at 4 times and both were significantly decreased when ischemic conditioning stimulation was applied. The maximum reductions in SEP amplitude and the VAS value were 26.1% and 21.2%, respectively, during ischemic conditioning stimulation. After-effect was observed 5 min after removal of the conditioning stimulation. The present study revealed that heterotopic ischemic stimulation attenuated the late component of SEP induced by electrical tooth stimulation, triggering diffuse noxious inhibitory controls (DNIC) and after-effects in the trigeminal nerve territory. It was also suggested that the DNIC effect differs, depending on the intensity, kind, and quality of the test and conditioning stimuli.     

改良式固定型马里兰桥修复老年前牙缺失的临床效果观察

目的 探讨运用改良式固定型马里兰桥修复老年患者前牙缺失的可行性,并对修复的方法设计、修复体制作过程及适应证进行总结.方法 选择个别前牙缺失,存在不同程度邻牙松动、牙龈萎缩、牙根暴露等体征的老年患者24例,运用改良式固定型马里兰桥修复缺失牙,并对完成修复的病例随访3～5年.结果 修复成功率为87.5%.24例患者有3例修复体脱落,需重新粘接;其余修复体未见明显松动.基牙无松动,桥体下方牙龈无明显红肿,患者对修复体的使用与外观效果均感满意.12例患者存在不同程度牙结石;2例患者存在舌侧轻度异物感,经过对症处理后效果满意.结论 改良式固定型马里兰桥修复老年前牙缺失具有磨牙少、效果美观,并能同时固定松动牙邻牙等优点,修复效果可靠.但其远期效果有待进一步观察.     

A midface swelling in a child – A possible diagnostic dilemma

A lump on the midface of a child can pose as a diagnostic dilemma. There is a wide variety of possible differential diagnoses, ranging from simple benign conditions such as a sebaceous cyst, dermoid cyst, lipoma, neuroma and neurofibroma, to potentially devastating conditions such as odontogenic myxoma.A case of a child in which the formulation of a definite diagnosis was clinically and histologically challenging is presented.     

发育性偏颌畸形的整形外科矫治

目的探讨发育性偏颌畸形的外科矫治方法。方法通过对21例发育性偏颌畸形患者的畸形部位与程度，分别采用LefortⅠ型截骨、下颌升支矢状劈开、颏部水平截骨、下颌骨外板截除、下颌骨外板移植等项整形手术治疗，并就该类患者颌面结构特征、手术方式的选择及疗效进行了回顾性分析。结果自1997年7月至2003年10月共治疗发育性下颌偏斜畸形21例，根据不同的类型采用相应的手术方法，获得了满意面部形态和殆功能。结论发育性偏颌畸形，根据不同类型运用相应的措施，通过恢复面部骨性轮廓支架和殆关系，配合术前术后的正畸治疗，可获得满意的临床效果。     

下颌角截骨术与下颌角外板矢状劈开术联合矫治低角型下颌角肥大

目的：下颌角肥大有多种式术可选,对于低角型下颌角肥大,往往一种式术很难达到满意的矫治效果,本文选择了一组低角型下颌角肥大患者,来研究下颌角截骨术与下颌角外板矢状劈开术联合应用治疗低角型下颌角肥大的治疗效果。方法：选择本科室2005年8月～2005年11月间治疗的24例低角型下颌角肥大患者,完善术前检查与分析。在全麻下应用下颌角截骨术与下颌角外板矢状劈开术进行联合矫治。术后观察治疗效果,并在8周后对所有患者进行随访,调查患者满意度。结果：所有24例患者矫治后Ⅰ期愈合,所有患者下颌角角度增大,两下颌角间宽度明显减小,达到了下颌角的正常美学标准。8周后随访,所有患者均对治疗效果表示满意。结论：下颌角截骨术与下颌角外板矢状劈开术联合应用,可有效地矫治低角型下颌角肥大,使患者下颌角达到一个理想的美学标准。     

局部注射VEGF对大鼠正畸牙齿移动的影响

目的：观察局部注射重组鼠的血管内皮生长因子(rrVEGF)对大鼠正畸牙齿移动的影响，探讨VEGF在正畸牙齿移动中的作用机制。方法：45只雄性SD大鼠，牵引其上颌第一磨牙近中移动，实验中分别将rrVEGF及生理盐水注射入实验组及对照组大鼠右侧上颌第一磨牙腭侧的骨粘膜下，于实验前3天开始注射，每3天一次。分别在加力l、3、7、14、2l天后记录上颌第一磨牙移动距离。然后将各组动物处死，用HE染色观察牙周组织变化情况并采用免疫组织化学方法对组织中表达的VEGF进行分析。结果：实验组大鼠压力侧破骨细胞教和成骨细胞数在实验全过程中均多于对照组，而且，实验组大鼠牙齿移动距离明显大于对照组。结论：进一步证实VEGF作为旁分泌因子，参与了牙齿移动过程中的牙周组织改建，内源性VEGF和注射VEGF都使牙齿移动量显著增加。因此，VEGF在正畸牙齿移动的机制中具有重要意义。     

A clinical and radiologic study of autotransplanted impacted canines

The aim of the present study was to evaluate the clinical and radiologic results of 20 autotransplantations of impacted canines performed in the Orthodontic and Pedodontic Department of the University of Geneva between 1979 and 1988. The sample, divided into two different age groups (group A: 13–20 years; group B: 20–48 years), demonstrated persistence of pulp vitality in 80% of the cases in group A, whereas routine endodontic treatment was instituted in all cases of group B. Periodontal healing was noted in 90% of the cases in group A, and in 70% of the cases in group B. The present clinical and radiologic data indicate that impacted canines can be transplanted at any age with good prognosis and are an alternative to orthodontic repositioning in selected cases of canine impaction.     

Relationship of clonogenic capacity to plating efficiency and vital dye staining of human periodontal ligament cells: implications for tooth replantation

The survival rate of avulsed permanent teeth following replantation is affected primarily by the duration of the extra-alveolar period and the nature of the storage conditions. These factors are believed to strongly affect the viability of periodontal ligament (PL) cells but in vitro assays of cell viability based on vital dye assays are only weakly correlated with the tooth survival rate after replantation. The aim of the present study was to examine the relative dependence of cell membrane integrity, attachment and clonogenic capacity of human PL cells on the temperature and duration of the extra-alveolar period and the type of storage medium. Twenty-four premolar teeth were extracted for orthodontic reasons from 9 patients 11–18 years of age. Teeth were maintained at 4°C or 23°C for 15, 30, 60 or 120 min in either milk or dry conditions. Cell membrane integrity was determined by BCECF/AM dye inclusion. Plating efficiency was determined by measurement of cell attachment at 3 and 6 h. The clonogenic capacity of progenitor cells was estimated by limiting dilution and colony counts. For all assays teeth stored in milk at 4°C showed the highest percentages of BCECF positive, attached cells with clonogenic capacity. Increased storage time (15–120 min) was associated with a 50% relative reduction of BCECF staining and a 5-fold relative reduction of cell attachment regardless of storage conditions. However, the clonogenic capacity of progenitor cells decreased 25-fold over the same duration of storage. These data demonstrate that in vitro assays of clonogenic capacity are much more sensitive to extra-oral storage time and storage conditions than dye inclusion or cell attachment. We suggest that in comparison with in vitro measures of cell membrane integrity, the clonogenic capacity of PL cells is more closely linked to tooth survival rate, probably reflecting the capacity of PL progenitor cells to recolonize the root surface after replantation.     

Stereotactic endoscopic treatment of colloid cysts of the third ventricle

Summary In order to avoid invasive procedures (transfrontal, transcallosal) in the surgical treatment of colloid cysts the stereotactic aspiration technique was introduced by Bosch, RÄhn and Backlund in 1978. The viscosity of the intracystic colloid and the displacement of the cyst away from the aspiration needle are possible reasons for unsuccessful aspiration. GT-guided stereotactic endoscopic technique gives the opportunity to fenestrate the cyst wall under direct visual control.After CT-guided stereotactic puncture of the right lateral ventricle with the foramen of Monro as target a steerable endoscope is introduced and the foramen of Monro is passed. The wall of the cyst is fenestrated and coagulated by means of monopolar (or laser) coagulation.Using this technique we have treated four patients with colloid cysts. Immediately postoperatively all of them were relieved of their complaints and have been symptomfree for a mean follow up period of twelve months. Studies of cerebrospinal fluid flow patterns, performed prior to and every six months after the endoscopic intervention, confirmed a remarkable reduction of foraminal obstruction.     

大鼠第三脑室一氧化氮合酶阳性触液神经元的观察

应用ＮＡＤＰＨ－ｄ组织化学方法研究脑室系统的一氧化氮合酶（ＮＯＳ）阳性触液神经元。结果发现，ＮＯＳ阳性触液神经元主要见于第三脑室。根据胞体所在位置，第三脑室ＮＯＳ阳性触液神经元可有３种形式：（１）室管膜内触液神经元；（２）室管膜下或远位触液神经元，其突起伸入第三脑室室管膜上皮之间，这些ＮＯＳ阳性触液神经元有的来自室旁核或室周核；（３）室管膜上触液神经元，其胞体位于室管膜表面。本文首次报道了第三脑室ＮＯＳ阳性触液神经元，这种触液神经元的分布类型基本和其他递质触液神经元相类同，并讨论了ＮＯＳ阳性触液神经元的功能。