拔除上颌切牙病例的正畸治疗

目的探讨拔除上颌切牙及下颌双尖牙进行正畸治疗病例的正畸治疗特点。方法采用回顾性研究的方法，对11名由于各种原因需要拔除上颌切牙并同时需要拔除下颌双侧第一双尖牙进行正畸治疗的患者进行研究。用电子游标卡尺进行模型测量，通过模型测量计算Bolton指数分析该类患者拔牙治疗后上下颌牙量的协调性。并通过患者的正畸治疗总结该类患者的治疗特点及矫治要点。结果：该类患者治疗后的Bolton指数分别为前牙比79．71％、后牙比91．75％，虽大于正常均数，但差异不大。11名患者上下颌牙量的不调量在0．5—2．82mm间。结论：拔除上颌切牙及下颌双尖牙治疗的患者，上下颌牙量基本协调，恰当的正畸矫治可以使患者获得良好的矫治效果。     

Measuring Beliefs about Orthodontic Treatment: A Questionnaire Approach

Objectives : Few studies have examined what parents and orthodontists expect from and value about orthodontic treatment. In this study, we designed and tested a questionnaire to outline what drives consumer demand for children's orthodontic care. Further, we present data from the questionnaire to illustrate how expectations and values pertaining to orthodontic treatment relate to sociodemographic variables. Methods : Subjects were 220 Pennsylvania orthodontists and 220 parents at a university orthodontic clinic who were administered a questionnaire designed to assess what parents and orthodontists value about and expect from orthodontic treatment. Items for the questionnaire were developed via a qualitative, telephone interview process. Data were analyzed using factor analysis and reliability analysis for scale development, and analysis of variance for preliminary validity assessment. Results : Through factor analysis, the questionnaire was reduced from 84 to 52 items, and eight scales were examined: expected treatment benefits, expected treatment risks (short- and long-term), expected treatment inconveniences, value of treatment benefits, value of risks (short- and long-term), and value of treatment inconveniences. For parents, the reliability for all scales was in the acceptable range. For orthodontists, only the “short-term risks” scale failed to attain an acceptable reliability. Preliminary validity was assessed through examining relationships between demographic variables and subscale scores. For parents, income, father's education level, and sex of respondent were related to treatment expectations and values. For orthodontists, age, sex, and patient volume were related to treatment values. Conclusions : The questionnaire developed in the present study was found to be practical and reliable for use with providers and consumers of orthodontic care and can be used to explore factors affecting the demand for orthodontic care. Implications of possible unrealistic treatment expectations on the part of orthodontists and parents also are discussed.     

周期性牵张力加载下人牙周膜细胞中血管内皮生长因子表达变化的研究

目的：观察周期性牵张力作用下，体外培养的人牙周膜成纤维细胞(human periodontal ligament fibroblasts，HPLFs)中血管内皮生长因子(Vascular endothelial growth factor，VEGF)表达的变化，以探讨机械力介导下牙周组织改建的机制。方法：通过体外细胞培养加载系统，采用周期性牵张力(每分钟6个循环，12％形变量)加载l、3、5、7d，用免疫组化和原位杂交技术，观察VEGF在HPLFs中的表达。结果：HPLFs在体外表达VEGF，其蛋白水平及mRNA水平的表达从加力ld开始升高，5d达到高峰，在加力7d开始下降。结论：在一定条件下，周期性牵张力可显著影响HPLFs VEGF的蛋白和mRNA水平的表达，进一步证实机械力作用下，VEGF参与了牙周组织改建，在正畸牙齿移动的机制中具有重要意义。     

3D功能模型在口腔正畸中的应用现状与研究进展

在正畸临床工作中,牙颌模型是患者初始信息和疗程记录的良好载体,也是诊断分析的重要资料。在治疗过程中,可通过研究模型来了解当前的治疗情况及矫治进展,并及时调整治疗方案,达到最佳疗效。石膏模型存在固化时间长、边缘不清楚、取模变性等缺点,难以快速准确地测量数据并对治疗结果的预测存在一定的局限性。伴随着科学技术的不断发展,石膏模型已很难满足正畸医师的需求。3D功能模型技术的发展为数字化时代下的正畸治疗带来了巨大变化。3D功能模型技术广泛应用于数字化建档、三维诊断及治疗方案的辅助设计、正畸矫治、正畸材料设备制造、科研教学等。3D功能模型技术应用带动了口腔正畸的发展,该文就3D功能模型在口腔正畸领域的应用进行综述。     

Removable splint with locking attachments for maxillary distraction osteogenesis with the RED system

The external traction hooks of the intraoral splint used to control traction forces applied to the maxilla with the rigid external distraction system represent a major barrier to surgical procedures. The purpose of this article is to introduce a removable intraoral splint with locking attachments that can be placed post-surgically immediately before distraction, facilitating surgery and consequently reducing the operative time. Fifteen cleft lip and palate patients underwent maxillary distraction osteogenesis using a rigid external distraction device in combination with the proposed removable splint that was fixed onto the maxillary teeth to provide anchorage. Initial records showed severe maxillary hypoplasia and negative overjet. The removable splint was fabricated using 1.5-mm diameter stainless-steel rigid orthodontic wires soldered to the locking attachments (Y&B Products LP, Chiang Mai, Thailand), making possible its placement post-surgically. Stable splint fixation was achieved prior to the distraction procedure and the desired treatment goals were reached. No complications inserting or removing the splint post-surgically, including pain or discomfort, were observed. The use of the removable splint with locking attachments has proved to be a highly effective fixation approach to manage the severely hypoplastic maxilla, eliminating lip constraints resulting from scarring, and allowing for easier, more deliberate and careful dissection.     

牙周病致前牙间隙患者的无托槽隐形矫治初探

目的 应用无托槽隐形矫治技术治疗因牙周病导致前牙间隙的患者,评价矫治过程中患者牙周状况的变化,以期为临床提供参考.方法 选取7例因轻、中度牙周炎导致前牙间隙的患者,矫治前患者前牙间隙为3.0～4.5 nnn,平均3.4 mm.应用无托槽隐形矫治技术进行正畸治疗,关闭前牙散在间隙.观察矫治前和矫治1、3、6个月患者牙龈探诊出血(bleeding on probing,BOP)阳性位点百分比和平均探诊深度;评价矫治前和矫治1、6个月上前牙釉质牙骨质界至牙槽嵴顶的距离(CEJ-ABC距)的变化.结果 疗程4～6个月,矫治后所有患者牙间隙完全关闭,矫治3、6个月BOP阳性位点百分比分别为1.2%,1.8%,与矫治前(0%)相比,差异均无统计学意义(P>0.05);矫治1、3、6个月患者平均探诊深度分别为(1.49±0.13)、(1.58±0.11)、(1.57±0.15)mm,与矫治前[(1.50±0.12)mm]相比,差异均无统计学意义(P>0.05).矫治1、6个月上前牙间CEJ-ABC距与矫治前相比,差异均无统计学意义(P>0.05).结论 无托槽隐形矫治技术可用于轻、中度牙周病致前牙间隙的患者,短期观察未见牙周组织损伤.     

狗牙周膜血管构筑及正畸力作用下的即时改变

将狗一侧下颌前磨牙施以200g近中水平向正畸力,作用时间为2h,另一侧作为对照组进行自身对照,分别将甲醛墨汁和树脂灌注液经双侧颈外动态插管和下牙槽动脉插管灌入牙周膜血管,用光镜和实时图像分析仪观察分析黑汁切片,用扫描电镜观察牙周膜微血管铸型,结果显示,牙周膜微血管中有形态特殊的血管吻合支和毛细血管襻;在牙周膜与牙龈、牙髓、牙槽骨和邻牙牙周膜之间存广泛的交通支,形成一个有机的牙周血运网络系统;一些微静脉在穿出Volkman‘s管前形成“储水池”样膨大结构,借助于扫描电镜,可以从微血管铸型上的血管内皮细胞核压迹的特征来判别微动脉和微静脉,定量分析结果显示实验组牵张区牙周膜微血管体密度大于对照组对应区;实验组受压区牙周膜微血管体密度小于对照组对应区。     

Vertical and Orovestibular Forces Generated by Beta-Titanium and Stainless-Steel Rectangular Wires in Labial and Fully Customized Lingual Bracket Systems

This study aimed to investigate the force values exerted from rectangular wires when combined with conventional labial and fully customized lingual appliances under predefined, idealized activation. Fully customized lingual brackets of two brands Incognito™ (3M Unitek, Monrovia, CA, USA) and WIN (DW Lingual Systems, Bad Essen, Germany) and labial brackets of another brand, discovery^® MIM and discovery^® smart systems (Dentaurum, Ispringen, Germany), were chosen. Stainless-steel and beta-titanium wires of 0.018” × 0.025” were examined. For Incognito^TM, 0.0182” × 0.025” beta-titanium wires were tested. Intrusion/extrusion and orovestibular movements were performed in a range of 0.2 mm, and the forces were recorded for each 0.1 mm of the movement. Mean values and standard deviations were calculated for all measurements, and ANOVA was performed for statistical analysis. Slight differences were observed between the forces generated from beta-titanium and stainless-steel wires. The same wire generated in some cases 5–53% higher forces with the lingual appliance due to the vertical orientation of the long walls during intrusion/extrusion and increased wire stiffness at the anterior region. Beta-titanium and stainless-steel 0.018” × 0.025” wires can generate similar force values during the final stages of the orthodontic therapy; thus, possibly only one of the two alloys could be used in each orthodontic wire sequence.     

Endodontic-orthodontic relationships: a review of integrated treatment planning challenges

Literature review There is a paucity of information on the concise relationship between endodontics and orthodontics during treatment planning decisions. This relationship ranges from effects on the pulp from orthodontic treatment and the potential for resorption during tooth movement, to the clinical management of teeth requiring integrated endodontic and orthodontic treatment. This paper reviews the literature based on the definition of endodontics and the scope of endodontic practice as they relate to common orthodontic-endodontic treatment planning challenges. Literature data bases were accessed with a focus on orthodontic tooth movement and its impact on the viability of the dental pulp; its impact on root resorption in teeth with vital pulps and teeth with previous root canal treatment; the ability to move orthodontically teeth that were endodontically treated versus nonendodontically treated; the role of previous tooth trauma; the ability to move teeth orthodontically that have been subjected to endodontic surgery; the role of orthodontic treatment in the provision for and prognosis of endodontic treatment; and, the integrated role of orthodontics and endodontics in treatment planning tooth retention. Orthodontic tooth movement can cause degenerative and/or inflammatory responses in the dental pulp of teeth with completed apical formation. The impact of the tooth movement on the pulp is focused primarily on the neurovascular system, in which the release of specific neurotransmitters (neuropeptides) can influence both blood flow and cellular metabolism. The responses induced in these pulps may impact on the initiation and perpetuation of apical root remodelling or resorption during tooth movement. The incidence and severity of these changes may be influenced by previous or ongoing insults to the dental pulp, such as trauma or caries. Pulps in teeth with incomplete apical foramen, whilst not immune to adverse sequelae during tooth movement, have a reduced risk for these responses. Teeth with previous root canal treatment exhibit less propensity for apical root resorption during orthodontic tooth movement. Minimal resorptive/remodelling changes occur apically in teeth that are being moved orthodontically and that are well cleaned, shaped, and three-dimensionally obturated. This outcome would depend on the absence of coronal leakage or other avenues for bacterial ingress. A traumatized tooth can be moved orthodontically with minimal risk of resorption, provided the pulp has not been severely compromised (infected or necrotic). If there is evidence of pulpal demise, appropriate endodontic management is necessary prior to orthodontic treatment. If a previously traumatized tooth exhibits resorption, there is a greater chance that orthodontic tooth movement will enhance the resorptive process. If a tooth has been severely traumatized (intrusive luxation/avulsion) there may be a greater incidence of resorption with tooth movement. This can occur with or without previous endodontic treatment. Very little is known about the ability to move successfully teeth that have undergone periradicular surgical procedures. Likewise, little is known about the potential risks or sequelae involved in moving teeth that have had previous surgical intervention. Especially absent is the long-term prognosis of this type of treatment. During orthodontic tooth movement, the provision of endodontic treatment may be influenced by a number of factors, including but not limited to radiographic interpretation, accuracy of pulp testing, patient signs and symptoms, tooth isolation, access to the root canal, working length determination, and apical position of the canal obturation. Adjunctive orthodontic root extrusion and root separation are essential clinical procedures that will enhance the integrated treatment planning process of tooth retention in endodontic-orthodontic related cases.     

正畸不同用氟方法预防釉质粘接面早期龋的超微结构观察

目的;测定应用氟化物的不同方法对釉质吸收氟离子的影响。方法：采用因固定正畸需要而拔除的双尖牙１２颗,随机分成对照组,酸蚀中用氟组和酸蚀后用氟组,每组牙釉质经酸蚀和不同用氟方法处理后,做扫描电镜检查。结果;酸蚀后用氟组釉质表面的反应产物最多,釉质吸收的氟离子最多。