Effects of cooling and heating of the tooth on pulpal blood flow in man

Abstract Laser Doppler flowmetry (LDF) was used to study the changes in pulpal blood flow (PBF) evoked by application of cold or heat to the palatinal surfaces of teeth 11 or 21 in nine young subjects. Switching from a thermode temperature of 33° to 5° G on average induced a slow decrease of PBF to about 80% of control, and also warming to 39°C evoked a small reduction in most subjects. Inter individual differences were large, however, and both cooling and warming sometimes triggered a rise in PBF. In contrast, skin blood flow, as recorded with LDF in the forearm, invariably rose during warming and fell during local cooling. The results suggested a more complex interaction between local and nervously mediated effects of moderate changes in temperature in the tooth pulp than skin, and that the previous held view of cold and heat decreasing and increasing PBF, respectively, is wrong.     

Eligible Veterans'' Choice Between VA-covered and Non-VA-covered Dental Care

Veterans who were eligible for dental care in Department of Veterans Affairs (VA) facilities at no monetary cost responded to a mailed questionnaire. Seventy-one percent were aware that they were actually eligible for VA dental care. However, only 48 percent reported the VA as their only or primary source of dental care. Eligibility status, perceived quality of VA dental care, use of VA medical care, perception that one's income meets expenses, and perceived need for dental care were significant correlates of using the VA as one's current source of dental care. Level of formal education, perception that one's income meets expenses, transportation pattern, geographic distance from a VA facility, and eligibility status were significant correlates of using the VA as one's current medical care source. Research on VA utilization offers the opportunity to study issues of access to, and use of, a large public health care system whose patients largely receive care at no monetary cost. Veterans' use of VA dental and medical care is apparently influenced by a wide variety of factors, ranging from barriers to access to non-VA systems, to characteristics of the VA delivery system itself, to need for treatment.     

刺梨汁对慢性氟中毒的影响及机理研究

用高氟饲料喂养大鼠６个月，复制出慢性氟中毒模型，再自由饮用刺梨汁３个月，探讨刺梨汁对慢性氟中毒的影响及机理。结果表明：刺梨汁可明显改善氟中毒的一般状况，对已形成的氟斑牙影响不大，但可促进尿氟排泄，降低血清和骨氟含量及尿羟脯氦酸含量，提高血清中维生素Ｃ、维生素Ｅ和血清、肝、肾ＧＳＨ含量，增强血、肝、肾ＧＳＨ－Ｐｘ和ＳＯＤ活性，降低血清、肝和肾ＬＰＯ含量，降低尿γ－ＧＴ和血清ＧＰＴ活性及肝ＴＧ含量，提示：刺梨汁具有明显桔抗慢性氟中毒作用，其机理可能是通过促进尿氟排泄和抗氧化作用。     

重度磨耗患者髁道运动学初步评价

评价重度磨耗患者后方髁道运动学特征 ,探讨髁状突运动与牙合重建的关系。方法 :运用Pantronic髁状突运动描记系统和D5ADenar全调节式咬合架 ,对 15例中老年重度磨耗患者后方髁道决定因素对牙合运动的影响 ,以及对 5例已完成咬合重建的重度磨耗患者髁道运动学特征进行初步评价。结果 :15例重度磨耗患者平均髁间距离为 ( 60 .72± 4.40 )mm ,迅即侧移量 (ISS) 1.3 5mm (右 )和 1.2 4mm (左 ) ,渐进侧移量 (PSS)为14 .65°(右 )与 17.11°(左 ) ,前伸髁导斜度 (PRO)为 2 3 .45°(右 )与 2 6.85°(左 ) ,非工作侧髁道值 (ORB)为 2 6.5 0° ,前伸髁导斜度与非工作侧髁道之间极相关 ,存在较小的Fisher角。结论 :咬合重建主要影响侧移量和Pantronic重复运动指数 (PRI)的大小 ,反映出下颌侧方边缘运动限制所恢复的程度。但牙合重建对非工作侧髁道没有明显的影响 ,运动道的变化并不能预测治疗的效果。     

Comparative study of oral conditions in schoolchildren of Strasbourg, France, 1974–85

A representative sample of 1650 children randomly selected in the 6-15-yr-old schoolchild population of Strasbourg was examined by well-calibrated examiners. The prevalence of caries was determined with the DMFT, DMFS and dft indices using bitewing radiographs. Plaque, calculus and gingival indices were also determined. The results obtained were compared with the initial study of 1974 performed in Strasbourg using the same epidemiologic methods. Whereas no important variations were observed in caries prevalence of primary teeth, a significant reduction of caries activity was observed in DMFT and DMFS indices in all age groups. There was a reduction of these two indices of respectively 32% and 33% in the 12-yr-old children. The reduction was the most significant on approximal surface lesions. A statistically significant decrease of the calculus and gingival indices was also observed between 1974 and 1984. A less significant decrease was observed for the plaque index.     

Treatment time analysis for extensive amalgam restorations

The treatment times for the fabrication of Extensive Amalgam Restorations (EAR) as recorded in a longitudinal clinical trial at the Dental School in Nijmegen were analyzed. 269 EAR's with different retention methods were made on molars by three operators. A mean total treatment time of 60 min was found. The factor operator had a significant influence on all treatment phases resulting in a 26% difference in total treatment time between operators. Also significant influences were found in some treatment phases for the factor retention, side location of the tooth and extension of the restoration. The results of this study with regard to treatment times must be considered from the perspective of the quality of the care provided.     

氟中毒和氟砷中毒对胃粘膜的影响

作者通过内窥镜对新疆奎屯地区氟中毒患者３５名，氟砷中毒患者３２名，对照组２５名的胃粘膜进行观察，旨在了解氟元素和砷元素对胃粘膜的影响，在３个组中慢性胃炎的炎症程度与炎症活动性有显著性差异。２个中毒组间无显著性差异。结果表明在高氟区和高氟砷区患者的胃粘膜层病理改变主要是任性氟中毒引起，单纯性砷中毒并无协同作用。     

地方性氟中毒家猪胫骨形态计量学的初步研究

本文应用 Mop-Videoplan 图象分析仪对氟中毒家猪胫骨进行了骨计量学的初步研究。四环素双标记后将家猪胫骨制备成骨磨片,在荧光及普通光学显微镜下测量了一系列骨计量学参数。结果表明,氟中毒导致家猪胫骨髓腔面皮质新骨体积明显增加,但其增加程度不与血氟呈正相关。新骨体积增加可能是造成临床 X 线氟骨症表现骨髓腔狭窄的原因。骨动力学研完表明,氟中毒造成四环素双标记明显减少,这可能与氟抑制骨组织的转换过程有关。