BACKGROUND & AIMS: :Tooth agenesis constitutes the most common anomaly of dental development in humans. In the majority of familial cases of hypodontia alone or in association with other anomalies, the mode of inheritance is autosomal dominant. In the present study, we have identified two distantly related consanguineous Pakistani kindreds with an autosomal recessive form of oligodontia with associated dental anomalies. Locus in this case has been mapped on chromosome 4p16.1-p16.3. The maximum two-point LOD score of 2.85 (theta=0.0) was obtained at markers D4S2925 and D4S2285. A maximum multipoint LOD score exceeding 4 was obtained at the same markers. Recombination events observed in affected individuals localized the disease locus between markers D4S412 and D4S2935, spanning a 9.24-cM region on chromosome 4p16.1-p16.3. Sequence analysis of candidate gene MSX1 revealed a novel recessive missense mutation resulting in substitution of alanine to threonine amino acid (p. A219T), located in the MSX1 homeodomain, which is important for DNA binding and protein-protein interaction. The mutation, p. A219T, is the first recessive mutation identified in MSX1.

背景与目标： : 牙齿发育不全是人类最常见的牙齿发育异常。在大多数单独或与其他异常相关的家族性牙体减少病例中，遗传方式是常染色体显性遗传。在本研究中，我们已经确定了两个远近相关的近亲巴基斯坦亲缘动物，它们具有常染色体隐性遗传形式的少齿症，并伴有相关的牙齿异常。在这种情况下，基因座已定位在4p16.1-p16.3染色体上。在标记D4S2925和D4S2285处获得2.85的最大两点LOD得分 (theta = 0.0)。在相同标记下获得的最大多点LOD得分超过4。在受影响的个体中观察到的重组事件将疾病基因座定位在标记D4S412和D4S2935之间，跨越染色体4p16.1-p16.3上的9.24 cM区域。候选基因MSX1的序列分析揭示了一种新的隐性错义突变，导致丙氨酸取代为位于MSX1同源结构域中的苏氨酸氨基酸 (p. A219T)，这对于DNA结合和蛋白质-蛋白质相互作用很重要。突变p. A219T是在msx1中鉴定出的第一个隐性突变。

BACKGROUND & AIMS: OBJECTIVE:To determine the level of student drop-out from UK dental schools and to establish if drop-out is increasing, remaining steady or decreasing.

DESIGN:Retrospective analysis of data from the University Statistical Record.

SETTING:UK dental schools 1989-1994.

SUBJECTS AND METHODS:The data covered all dental students entering and leaving dental schools during the relevant time period.

RESULTS:The drop-out rate from UK dental schools between 1989 and 1994 ranged from 8.4% to 16.8% and is equivalent to the output of two to three medium-sized dental schools. Drop-out rate was higher in the three most recent years studied (1992-1994; 14.8%) than in the three earliest years studied (1989-1991; 10.6%).

CONCLUSIONS:Student drop-out is a significant and increasing problem for UK dental schools. Unless controlled, it will result in fewer dentists qualifying in the UK and exacerbate shortages in qualified dentists that may occur in future years.

背景与目标： 目标 : 确定英国牙科学校学生辍学的水平，并确定辍学是增加，保持稳定还是减少。
设计 : 大学统计记录数据的回顾性分析。
设置 : 英国牙科学校1989-1994。
主题和方法 : 数据涵盖了相关时间段内进入和离开牙科学校的所有牙科学生。
结果 : 英国牙科学校1989年和1994的辍学率从8.4% 到16.8% 不等，相当于两到三所中等牙科学校的产量。最近三年 (1992-1994; 14.8%) 的辍学率高于最早三年 (1989-1991; 10.6%)。
结论 : 对于英国牙科学校来说，学生辍学是一个重大且日益严重的问题。除非受到控制，否则将导致英国的牙医资格减少，并加剧未来几年可能出现的合格牙医短缺。

BACKGROUND & AIMS: :Debt among Canadian university graduates is increasing, while money apportioned to federal and provincial needs-based student assistance programs has been decreasing since the 1990s. Dental students have had to absorb increased tuition fees at both the undergraduate and post-baccalaureate levels. Existing debt and high tuition fees may adversely influence a potential candidate"s decision to enroll in dental school. Likewise, debt incurred during the minimum 2 years of pre-dental education adds to the future debt load of dental graduates. It seems that few dental students can remain debt-free during their dental education, although data are lacking about the extent of debt among dental students and its impact on their career decisions. Government statistics focus primarily on tuition costs for baccalaureate-degree students. Tuition and clinic-related fees constitute a significant proportion of costs for dental students; moreover, university administrations perceive dentistry as an expensive curriculum. This first article of a 4-part series examines debt among dental students, both nationally and internationally.

背景与目标： : 自20世纪90年代以来，加拿大大学毕业生的债务正在增加，而分配给联邦和省级基于需求的学生援助计划的资金却在减少。牙科学生不得不在本科和学士学位后水平上吸收增加的学费。现有的债务和高昂的学费可能会对潜在候选人就读牙科学校的决定产生不利影响。同样，在至少2年的牙科前教育期间产生的债务增加了牙科毕业生未来的债务负担。尽管缺乏有关牙科学生的债务程度及其对职业决定的影响的数据，但似乎很少有牙科学生在牙科教育期间能够保持无债务状态。政府统计数据主要集中在学士学位学生的学费上。学费和诊所相关费用占牙科学生费用的很大一部分; 此外，大学管理部门认为牙科是一项昂贵的课程。由4部分组成的系列文章的第一篇文章研究了国内外牙科学生的债务。

BACKGROUND & AIMS: BACKGROUND:Ebstein anomaly is a rare and heterogeneous congenital heart defect affecting the tricuspid valve and right ventricular (RV) myocardium. Few studies have analysed the electrocardiographic features of Ebstein anomaly and none has addressed correlations with disease severity. METHODS:Patients with Ebstein anomaly who had undergone electrocardiography and cardiac magnetic resonance (CMR) within 6 weeks between 2001 and 2009 were included. Exclusion criteria were: associated congenital cardiac defect, previous RV myoplasty and/or reduction surgery, class I anti-arrhythmic drug therapy, and paced/pre-excited QRS. Standard electrocardiogram (ECG) findings were correlated with CMR-based RV measures and clinical profile. RESULTS:The mean age of the 63 study patients was 22 ± 13 years. An RV conduction delay (rsR' pattern in right precordial leads) was present in 45 patients (71%). The QRS duration correlated with anatomic RV diastolic volume (r = +0.56, P < 0.0001) and inversely with RV ejection fraction (EF; r = -0.62, P < 0.0001). The presence of QRS fractionation predicted greater atrialized RV volume (80 ± 31 vs. 45 ± 37 mL/m(2), P < 0.001). Normal QRS duration was associated with smaller anatomic RV diastolic volume (150 ± 57 vs. 256 ± 100 mL/m(2); P < 0.0001), higher RV EF (48 ± 6 vs. 34 ± 14%; P < 0.0001), higher oxygen consumption (VO(2)) at cardiopulmonary exercise (25.8 vs. 21.8 mL/kg/min, P = 0.05) and lower incidence of oxygen desaturation with exercise (25 vs. 65%, P = 0.02). CONCLUSION:Delayed and prolonged depolarization of the RV is common in patients with Ebstein anomaly. The QRS duration is a marker of RV enlargement and dysfunction. QRS fractionation is associated with a greater atrialized RV volume. A preserved surface ECG identifies a subset of patients with Ebstein anomaly with mild morphological and functional abnormalities and better clinical profile.

背景与目标：

BACKGROUND & AIMS: :Our objective was to evaluate changes in curriculum and culture within a research non-intensive dental school after implementation of programs supported by the NIH-NIDCR R25 Oral Health Research Curriculum Grant. We designed new curricular elements to foster an appreciation of research/discovery, an interest in academic/research careers, and application of biomedical/clinical advances to patient care. Funding was utilized to develop, implement, and assess a dedicated curricular track of continuous student research/scholarly activity throughout the four years of dental education. This track represented mandatory hours of didactic time exposing students to topics not traditionally included in dental curricula. Additionally, students were provided with customized flexible schedules to participate in elective "hands-on" mentored research/scholarly experiences at local, national, and international sites, including linkages to certificate, MS, and PhD programs. Funding was also used to support a wide array of faculty development activities that provided skill sets required to deliver integrated biomedical/clinical content, research-oriented evidence-based approaches to dental education, and translational case-based teaching methods emphasizing the application of new science/technologies to patient care. We measured changes in student, faculty, and institutional profiles/attitudes using traditional benchmarks, surveys, and focus groups. Comparisons were made between baseline data prior to R25 program initiation and data collected after years 3-4 of program implementation. Significant increases were demonstrated in: (1) student participation in research/scholarship, attendance at national meetings, research awards, publication of manuscripts, pursuit of advanced training/degrees, and expressions of interest in academic/research careers; (2) faculty participation in development activities, publication of manuscripts, and mentoring of students; and (3) increased institutional credibility within the university, supportive infrastructure for research/scholarship, and cultural expectations for academic excellence. Thus, we believe that the R25 programming changed the culture of our dental school, creating a supportive environment for research/scholarship, increasing academic productivity, and altering the attitudes of faculty/students.

背景与目标： : 我们的目标是在实施nih-nidcr R25口腔健康研究课程补助金支持的计划后，评估非密集型牙科学校课程和文化的变化。我们设计了新的课程元素，以促进对研究/发现的欣赏，对学术/研究职业的兴趣以及将生物医学/临床进展应用于患者护理。在整个牙科教育的四年中，资金用于开发，实施和评估持续的学生研究/学术活动的专用课程。此曲目代表了强制性的教学时间，使学生接触传统上不包括在牙科课程中的主题。此外，还为学生提供了定制的灵活时间表，以参加在本地，国家和国际站点上进行的选修 “动手” 指导的研究/学术经验，包括与证书，MS和博士学位课程的联系。资金还用于支持广泛的教师发展活动，这些活动提供了提供综合生物医学/临床内容所需的技能，以研究为基础的基于证据的牙科教育方法以及强调应用新的案例的基于案例的教学方法。科学/技术用于患者护理。我们使用传统的基准，调查和焦点小组来衡量学生，教师和机构概况/态度的变化。比较了R25计划启动前的基线数据和计划实施3-4年后收集的数据。显着增加的表现是 :( 1) 学生参与研究/奖学金，参加国家会议，研究奖，手稿的出版，追求高级培训/学位以及对学术/研究职业的兴趣表达; (2) 教师参与发展活动，手稿的出版，和指导学生; (3) 提高大学内部的机构信誉，支持研究/奖学金的基础设施以及对学术卓越的文化期望。因此，我们认为，R25编程改变了我们牙科学校的文化，为研究/奖学金创造了支持环境，提高了学术生产力，并改变了教师/学生的态度。

BACKGROUND & AIMS: PURPOSE:A low-temperature low-energy capillary-tube-based argon micro-plasma system was applied to disinfect Streptococcus mutans-containing biofilm. MATERIALS AND METHODS:The micro-plasma system uses a hollow inner electrode that is ignited by a radio-frequency power supply with a matching network. The energy content was analyzed using optical emission spectroscopy. The micro-plasma-induced effect on a biofilm cultured for 24 or 48 h with a working distance of ≈3 mm at low temperature was evaluated. The morphologies of the treated live/dead bacteria and the produced polysaccharides after micro-plasma treatment were examined. RESULTS:Scanning electron microscopy images and staining results show that most of the S. mutans on the treated biofilm were acutely damaged within a micro-plasma treatment time of 300 s. CONCLUSIONS:The number of living bacteria underneath the treated biofilm greatly decreased with treatment time. The proposed micro-plasma system can thus disinfect S. mutans on/in biofilms.

背景与目标：

BACKGROUND & AIMS: PURPOSE:The purpose of this study was to determine the quantity and quality of DNA extracted from a dental bite impression wafer immediately after impression and after 12 months of home storage. The authors' hypothesis was that the wafer would retain sufficient DNA with appropriate genetic markers to make an identification match. METHODS:Two impression wafers (Toothprints(®) brand) were administered to 100 3- to 26-year-olds. A cotton swab was used as a control. DNA from wafers stored for 12 months at home were compared to DNA collected at time 0 and compared to swabs at specific sites to determine quality and accuracy. The amount of DNA captured and recovered was analyzed using MagAttract technology and a quantitative real-time polymerase chain reaction. Capillary gel electrophoresis was performed to determine the quality of the DNA profiles obtained from the wafers vs those generated from the swabs of each subject. RESULTS:Average DNA concentration was: 480 pg/μL (wafer at time 0); 392 pg/μL (wafer after 12 months kept by subjects); and 1,041 pg/μL (buccal swab). Sufficient DNA for human identification was recovered from all sets of wafers, producing clear DNA profiles and accurate matches to buccal swabs. No inhibitors were found that could interfere with DNA profiling. CONCLUSIONS:Toothprints® impression wafers can be useful for DNA collection and child identification. After 12 months, the wafer was still usable for DNA capture and identification match.

背景与目标：

BACKGROUND & AIMS: BACKGROUND:The degree of involvement of left ventricular inflow tract obstruction is the predominant factor determining outcome in Shone's anomaly. In this series of patients with Shone's anomaly, we evaluated the impact of mitral valve (MV) repair strategies performed to correct the components of this anomaly on growth of the valve and long-term functional outcome in children. METHODS:In the last 25 years, 45 children, mean age 5.16 ± 5.0 years (median, 3.9; range, 2 months-16.8 years), underwent surgical correction of Shone's anomaly. Coarctation of the aorta was found in 40%, subaortic stenosis due to fibromuscular hypertrophy was found in 55%, and subvalvar membrane was found in 66% of these patients. Left ventricular inflow tract obstruction was brought about by fused commissures with dysplastic and shortened chordae in 53.3%, valve hypoplasia in 11.1%, supravalvar mitral ring in 100%, and parachute valve in 17.8 of patients%. RESULTS:Various repair strategies were performed according to the presenting morphologic characteristics in patients with either previously corrected or concomitant correction of the left-sided obstructive lesions. Mean duration of follow-up was 17.5 ± 1.5 years. Freedom from reoperation was 52.8% ± 11.8%, wherein 23 patients underwent repeated MV repair and 1 patient underwent MV replacement after failed attempts at repair. The cumulative survival rate was 70.3% ± 8.9% at 15 years. Severity and type of mitral abnormalities, left ventricular outflow tract lesions, and pulmonary hypertension are risk factors for reoperation and mortality (p < 0.05). CONCLUSIONS:Repair allowed growth of the MV. Long-term outcome of MV repair in Shone's anomaly is related to the degree that the obstructive lesions can be relieved.

背景与目标：

BACKGROUND & AIMS: OBJECTIVES:To compare peri-implant bone and soft-tissue levels of immediately non-occlusally loaded vs. non-submerged early loaded implants in partially edentulous patients up to 14 months after placement. MATERIAL AND METHODS:Fifty-two patients were randomized in five Italian private practices: 25 in the immediately loaded group and 27 in the early loaded group. To be immediately loaded, single implants had to be inserted with a torque of > or = 30 N cm, and splinted implants with a torque of > or = 20 N cm. Immediately loaded implants were provided with non-occluding temporary restorations within 48 h. After 2 months, the provisional restorations were placed in full occlusion. Implants were early loaded after 2 months. Final restorations were provided 8 months after placement. Blinded assessors evaluated peri-implant bone and soft-tissue levels. RESULTS:Fifty-two implants were immediately loaded and 52 were early loaded. No drop-out occurred. One single immediately loaded implant failed 2 months after placement. Both groups gradually lost peri-implant bone in a highly statistically significant manner at 2, 8, and 14 months. After 14 months, patients of both groups lost an average of 1.1 mm of peri-implant bone. There were no statistically significant differences between the two loading strategies for peri-implant bone and soft-tissue level changes (P > 0.05). After 14 months, the position of the soft tissues did not change significantly from baseline (delivery of the final restorations 8 months after placement). CONCLUSIONS:There were no statistically or clinically significant differences between immediate and early loading of dental implants with regard to peri-implant bone and soft-tissue levels as evaluated in the present study.

背景与目标：

BACKGROUND & AIMS: OBJECTIVE:To determine the prevalence and distribution of dilaceration in all tooth groups by using radiographs. STUDY DESIGN:The sample included 953 periapical intraoral radiographs and 488 panoramic radiographs from different caucasian patients. The ages of the patients ranged from 18-65 years. Dilaceration of the root was detected by measuring the degree of deviation from the long axis (deviation ł 90 degrees), and evaluating the "bull's eye" appearance. The prevalence of root dilaceration for each tooth-type was expressed in percentages. RESULTS:The teeth showing the highest prevalence of root dilaceration were mandibular third molars (24.1%), maxillary first molars (15.3%), second molars (11.4%) and third molars (8.1%). In the mandible, dilacerations were less common than in the maxilla. CONCLUSIONS:In the adult population examined in Croatia, dilaceration was most frequently found to affect posterior teeth.

背景与目标：

BACKGROUND & AIMS: :The Athens University, School of Dentistry, accepted the challenge to organize the Dental Health Services in the Athens 2004 Olympic and Paralympic Games in order to provide the best quality of oral health services to the athletes, coaches, escort members and Olympic Village personnel. Data from the whole activity protocol of the Athens 2004 Games Dental Health Services - the reception, admission and treatment protocols, the facilities and the infrastructure, the number of cases treated per specialty and the experience gained - were recorded. During the Olympic Games, there were more than 1400 dental cases in more than 650 patients, elite athletes, escort members, coaches and staff of the Olympic Village. Among them 313 fillings, 100 root canal therapies, 57 mouthguards and 9 dental trauma cases were treated. During the Paralympic Games, there were more than 240 dental cases in more than 220 patients. Among them 73 fillings, 12 root canal therapies, 21 extractions and 3 dental trauma cases were treated. In such events, highly trained dentists are needed and if possible, specialized in operative dentistry or endodontics. The role of team dentist seems to be of great importance.

背景与目标： : 雅典大学牙科学院接受了在雅典2004奥运会和残奥会上组织牙科保健服务的挑战，以便为运动员，教练，护送成员和奥运村人员提供最优质的口腔保健服务。记录了来自雅典2004运动会牙科保健服务的整个活动协议的数据-接收，准入和治疗协议，设施和基础设施，每个专业治疗的病例数以及获得的经验。奥运会期间，奥运村650多名患者、优秀运动员、护卫队员、教练员和工作人员共发生了1400多例牙病病例。其中补牙313例，根管治疗100例，护齿57例，牙外伤9例。残奥会期间，220多名患者中有240多个牙科病例。其中73例补牙，12例根管治疗，21例拔牙和3例牙外伤。在这种情况下，需要训练有素的牙医，如果可能的话，需要专门从事牙科手术或牙髓学。团队牙医的角色似乎非常重要。

BACKGROUND & AIMS: :The aim of this study was to assess the prevalence of dental caries in the primary dentition and associated variables in low socioeconomic preschool children enrolled in public nursery schools in Juiz de Fora, Minas Gerais, Brazil. Four public institutions were selected by geographic criteria (two in the central region and two in the peripheral region). The study population comprised 338 children (181 boys; 157 girls) aged 2-6 years old. Dental caries was recorded using the decayed, missing, and filled teeth (dmf-t) index. Among the examined children, 50.6% were caries-free. The mean dmf-t index was 2.03. It was higher in the peripheral nursery schools (p<0.01). A trend towards a difference between sexes (p = 0.06) was observed. Logistic regression analysis selected a previous child's visit to dentist (p<0.001), geographic location of the public nursery school (p<0.01), and age (p<0.01) as predictive variables for the dmf-t index. The study showed the need for an oral health program for this population, including both curative and preventive measures in order to achieve the WHO/FDI goals for the year 2000, namely 50% of children free of caries at age 5-6 years.

背景与目标： : 这项研究的目的是评估在巴西米纳斯吉拉斯州Juiz de Fora的公立托儿所就读的低社会经济学龄前儿童的主要牙列中龋齿的患病率和相关变量。根据地理标准选择了四个公共机构 (两个在中部地区，两个在外围地区)。研究人群包括2-6岁的338名儿童 (181名男孩; 157名女孩)。使用腐烂，缺失和填充的牙齿 (dmf-t) 指数记录龋齿。在接受检查的儿童中，有50.6% 人没有龋齿。平均dmf-t指数为2.03。在外围托儿所中较高 (p<0.01)。观察到性别差异的趋势 (p = 0.06)。Logistic回归分析选择了以前的儿童去看牙医 (p<0.001)，公立托儿所的地理位置 (p<0.01) 和年龄 (p<0.01) 作为dmf-t指数的预测变量。该研究表明，需要为这一人群制定口腔保健方案，包括治疗和预防措施，以实现世卫组织/外国直接投资2000年的目标，即50% 5-6岁无龋齿儿童。

BACKGROUND & AIMS: :Müllerian duct anomalies include a wide spectrum of genital tract defects resulting from a development alteration of the genital tract. An 11-year-old girl with a hybrid septate variety uterus with left hemi-obstruction was identified. Beside preoperative imaging evaluation done with ultrasound, magnetic resonance, and hysterosalpingography, a combined laparoscopic and hysteroscopic procedure was fundamental for the diagnosis. The surgical procedure also allowed us to perform a successful and safe treatment. We propose that the American Fertility Society classification of these anomalies should be revised and that hybrid entities should be considered in the differential diagnosis of genital tract malformations.

背景与目标： : 苗勒管异常包括由生殖道发育改变引起的广泛的生殖道缺陷。确定了一名11岁的女孩，该女孩患有杂种子宫，伴有左半梗阻。除了通过超声，磁共振和子宫输卵管造影进行术前影像学评估外，腹腔镜和宫腔镜联合手术是诊断的基础。外科手术也使我们能够进行成功且安全的治疗。我们建议应修订美国生育协会对这些异常的分类，并应在生殖道畸形的鉴别诊断疾病中考虑混合实体。

BACKGROUND & AIMS: :The placement of dental implants in the pterygomaxillary region can be advantageous in maxillary complete arch fixed implant-supported prosthetic rehabilitations to avoid bone grafting and sinus elevation surgeries. Pterygomaxillary implants improve implant biomechanics by eliminating distal cantilevers and increasing the anteroposterior spread with reported mean implant survival rates comparable to traditional implant sites. Although only minor surgical complications have been reported in the literature with the placement of dental implants in the pterygomaxillary region this clinical report describes a major surgical complication involving the displacement of a dental implant into the pterygoid fossa.

背景与目标： : 在上颌完全弓固定植入物支持的假体康复中，在翼状翼状区域放置牙科植入物可能是有利的，以避免植骨和鼻窦抬高手术。翼状翼状植入物通过消除远端悬臂并增加前后扩散来改善植入物的生物力学，据报道，平均植入物存活率可与传统植入物部位相媲美。尽管在文献中仅报道了在翼状翼状区域放置牙科植入物的较小的手术并发症，但该临床报告描述了一种主要的手术并发症，涉及将牙科植入物移位到翼状窝中。

BACKGROUND & AIMS: Genome-mismatch scanning (GMS) is a new method of linkage analysis that rapidly isolates regions of identity between two genomes. DNA molecules from regions of identity by descent from two relatives are isolated based on their ability to form extended mismatch-free heteroduplexes. We have applied this rapid technology to identify the chromosomal region shared by two fifth-degree cousins with autosomal dominant iridogoniodysgenesis anomaly (IGDA), a rare ocular neurocristopathy. Markers on the short arm of human chromosome 6p were recovered, consistent with the results of conventional linkage analysis conducted in parallel, indicating linkage of IGDA to 6p25. Control markers tested on a second human chromosome were not recovered. A GMS error rate of approximately 11% was observed, well within an acceptable range for a rapid, first screening approach, especially since GMS results would be confirmed by family analysis with selected markers from the putative region of identity by descent. These results demonstrate not only the value of this technique in the rapid mapping of human genetic traits, but the first application of GMS to a multicellular organism.

背景与目标： 基因组错配扫描 (GMS) 是一种新的连锁分析方法，可快速分离两个基因组之间的同一性区域。根据两个亲戚的血统从同一性区域分离出DNA分子，这是基于它们形成扩展的无错配异双链体的能力。我们已应用这项快速技术来识别常染色体显性显性虹膜增生异常 (IGDA) (一种罕见的眼部神经病变) 的5分之2度近亲共有的染色体区域。恢复了人类6p染色体短臂上的标记，与并行进行的常规连锁分析的结果一致，表明IGDA与6p25连锁。未恢复在第二条人类染色体上测试的对照标记。观察到大约11% 的GMS错误率，在快速、第一筛选方法的可接受范围内，特别是因为GMS结果将通过家族分析来确认，该家族分析具有来自推定的同一性区域的选定标记通过下降。这些结果不仅证明了该技术在快速绘制人类遗传性状方面的价值，而且证明了GMS在多细胞生物中的首次应用。