"Fatigue on rest" and associated symptoms (headache, vertigo, blurred vision, nausea, tension and irritability) due to locally asymptomatic, unerupted, impacted teeth.

"Fatigue on Rest", headache, vertigo and the feeling of loss of balance, blurred vision, nausea, tension and irritability, were found to be prevalent amongst patients who had locally asymptomatic, unerupted impacted teeth. A comparative pressure sign was developed, which, when positive, confirmed the relationship between the impacted teeth and the medical symptoms. Removal of the impactions resulted in the alleviation of the symptoms. Stress and psychogenic factors are considered as trigger mechanisms, rather than as basic causes of the symptoms.     

片段弓技术矫治Angle Ⅱ~1类深覆合X线头影测量的研究

为研究采用片段弓技术,评价ＡｎｇｌｅⅡ１类深覆牙合矫治后对上颌牙、骨骼及面部软组织的影响,选择ＡｎｇｌｅⅡ１类高角深覆牙合病例２０例,治疗前１２～１４岁,对４个上切牙施加５０ｇ压低力,用腭杆及短口外弓加强支抗,每例患者于初诊时（Ｔ１）、初诊后半年戴矫治器时（Ｔ２）、上前牙压低前（Ｔ３）及压低半年后（Ｔ４）摄取侧位片。选择１７项参数,（Ｔ４－Ｔ３）－（Ｔ２－Ｔ１）表示参数半年机械矫治量。结果表明：单纯机械矫治半年后,上颌第一磨牙无前移,上颌中切牙水平后移量及垂直压低量分别为３．７、３．５ｍｍ,上齿槽座点水平后移及压低量分别为０．７、０．４ｍｍ,上下唇珠点平均后移分别为２．３、３．３ｍｍ。结论：（１）片段弓技术在整体压低上前牙的同时可有效控制后牙的支抗;（２）上中切牙后移量与上唇珠后移量约呈２：１的关系;（３）上齿槽座点骨改形不明显。     

Neuropsychological studies in children with elevated tooth-lead concentrations

Summary In contrast to blood-lead (PbB), tooth-lead concentrations (PbT) provide retrospective information about longterm, cumulative childhood lead-intake. From a basic sample of 458 school age children from the city of Duisburg (FRG), whose lead-concentrations in shed incisor teeth had been measured ( =4.6 ppm; range: 1.4–12.7 ppm), two extreme-groups of 26 children each (mean age: 8.5 years) with low ( =2.4 ppm) and elevated ( =9.2 ppm) PbT were selected. After pair-matching both groups for age, sex, and father's occupational status, these children were tested under double-blind precautions for intellectual performance (German WISC), for perceptual-motor integration (Göttinger Formreproduktionstest = GFT, Diagnostikum für Cerebralschädigung = DCS, Benton-Test), and for gross motor-coordination (Körper-Koordinationstest für Kinder = KTK). Significant (P<0.05) inferiority of the lead-children was found in two tests of perceptual-motor integration (increased GFT-errors; lower success rate for DCS). In addition a near significant (P<0.1) reduction of 5–7 IQ-points was determined in these children. Although this pilot study has provided some evidence for an association between childhood lead-exposure and neuropsychological impairment, this association cannot yet be considered proven, because the observed effects were discrete and statistically confirmed only in part, and because there was a slight prevalence of perinatal risk factors in the lead group. Further research to clarify the issue is necessary.Based on an MD-thesis (Hrdina 1978), as well as on papers presented at Arbeitstagung der Deutschen Gesellschaft für Hygiene und Mikrobiologie, October 2–3, 1978 in Mainz, and at the symposium on Toxic effects of Environmental Lead, May 10, 1979 in London (Hrdina and Winneke 1978; Winneke 1979)     

错畸形牙弓形态的模拟及比较

目的 :比较不同类型错牙合畸形的牙弓形态。方法 :采用三维测量仪精密测量正常牙合及 4组不同类型错牙合(ClassⅠ双颌前突、ClassⅡ1、ClassⅡ2 、ClassⅢ )的原始模型 ,圆锥曲线模拟其牙弓形态。结果 :不同类型错牙合牙弓形态的差异有显著性 ,甚至某些分组的上下颌之间牙弓形态的差异也有显著性。结论 :临床上弯制弓丝时采用单一的标准牙弓形态是不完全科学的 ,应考虑错牙合的不同类型及其矫治前不同的牙弓形态以防止畸形复发。     

抗生素糊剂充填乳牙根管疗效观察

目的 探索一种疗程短、疗效好、患儿及家长易接受的根管治疗方法.方法 选择需行根管治疗的患儿162例,常规根管清理,试验组用抗生素糊剂充填乳牙根管,对照组用氢氧化钙糊剂,比较两组疗效.结果 经1年随访观察,抗生素组和氢氧化钙组乳牙根管充填成功率差异无显著意义.结论 用抗生素糊剂一次充填乳牙根管疗程短、疗效好,值得临床推广使用.     

河南省青少年恒牙龋病流行状况调查

目的掌握河南省儿童青少年口腔疾病患病现状,为制订口腔保健规划与目标,合理配置口腔卫生保健资源提供科学依据。方法采用分层、不等比、多阶段、整群抽样方法,抽取河南省4个地市12,15,18岁年龄组儿童青少年6 959人(城乡、男女各半)进行口腔检查。结果河南省3个年龄组儿童青少年龋齿的患病率为28.2%,以窝沟龋和浅龋为主,恒牙龋均(DMFT)为0.54,龋患牙充填率为10.11%,需治龋牙86.71%为单面洞。结论河南省儿童青少年龋病患病率和充填率均较低,应加强龋病的早期检查和治疗,控制儿童青少年的龋患率。     

Temperospatial Expression of Matrix Metalloproteinases 1, 2, 3, and 9 During Early Tooth Development

Odontogenesis involves a complex series of processes including epithelial-mesenchymal interactions, morphogenesis, differentiation, fibrillogenesis, and mineralization. Extracellular (ECM) remodeling plays a critical role in the rapid morphological changes that accompany these events. It is proposed that matrix metalloproteinases (MMPs) participate in the remodeling of tooth-specific matrices that accompanies the developmental events. MMPs are zinc-requiring endopeptidases that are centrally involved in the controlled turnover of ECM components and are key to a varied range of developmental processes. Thus, the aim of this study was to examine the expression of MMPs 1, 2, 3, and 9 within the developing tooth germ of Wistar rats, using immunohistochemical localisation. During the bud stage, MMPs 1, 2, 3, and 9 were expressed within both epithelial and mesenchymal cells. Later on, during the cap stage, differential expression was observed; of note was the expression of MMP 3 within the enamel knot. This study reports the temperospatial expression of MMPs 1, 2, 3, and 9 during early tooth development, and points to them having a key role during this important developmental period.     

Caries Frequency and Nutrition Before,During and After World War II

This study was carried out in order to observe the changes in amino-peptidase activity which might occur in the palatal mucosa and gingiva of the rat in the initial phase of healing after tooth extractions. The material consisted of 115 male Sprague-Dawley rats. Amino-peptidase activity was studied at time intervals of 30 min., 1, 2, 4, 8, 16 hours and 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10 days after the extractions. The azocoupling principle was used for the histochemical demonstration of enzyme activity. However, the incubation solution was in gel form. A semipermeable membrane was placed between the tissue sections and the incubation medium in order to prevent enzyme diffusion and dissolving of enzymes into the incubation medium. The substrates used were N-aminoacyl 2-naphthylamines of L-leucine and L-arginine. Histological investigations were carried out simultaneously with the histochemical study. The principal increase in aminopeptidase activity occurred relatively late after the tooth extractions. The most intense staining was observed in 4- to 7-day wounds. During the same period the most active fibroblastic proliferation was observed histologically. The changes were demonstrable using both of the substrates. However, the staining was more intense when N-L-leucyl-2-naphthylamine was used as the substrate. By using N-L-arginyl-2-naphthylamine as the substrate, chloride ions caused a marked increase in staining intensity. It was thus assumed that aminopeptidase B would also be activated during the healing.     

Graded changes in enamel component volumes resulted from a short tooth bleaching procedure

AimTo test the hypothesis that changes in enamel component volumes (mineral, organic, and water volumes, and permeability) are graded from outer to inner enamel after a short bleaching procedure.Materials and methodsExtracted unerupted human third molars had half of their crowns bleached (single bleaching session, 3 × 15 min), and tooth shade changes in bleached parts were analyzed with a spectrophotometer. Ground sections were prepared, component volumes and permeability were quantified at histological points located at varying distances from the enamel surface (n = 10 points/location), representing conditions before and after bleaching.ResultsTooth shade changes were significant (p < 0.001; 95% CI = −1/−8; power = 99%), and most of the enamel layer was unaffected after bleaching, except at the outer layers. Multiple analysis of covariances revealed that most of the variance of the change in enamel composition after bleaching was explained by the combination of the set of types of component volume (in decreasing order of relevance: mineral loss, organic gain, water gain, and decrease in permeability) with the set of distances from the enamel surface (graded from the enamel surface inward) (canonical R² = 0.97; p < 0.0001; power > 99%).ConclusionsChanges in enamel composition after a short bleaching procedure followed a gradient within component volumes (mineral loss > organic gain > water gain > decrease in permeability) and decreased from the enamel surface inward.