Predicting the experience of dentinal caries or restorative dental treatment in adolescents using D1 and D3 visual caries assessments

Standardised epidemiological caries assessments used in oral health surveys have been shown to be poor at predicting whether a tooth surface will be treated restoratively when a patient visits a dentist. However, it has been argued that oral health surveys may be more relevant in determining needs at the level of an individual or groups of individuals. The objective of this study was to determine the discriminatory power of visual caries assessments at two thresholds (D₁ & D₃) in adolescents of average age 12.1 years to predict experience of dentinal caries 3 years later or the experience of restorative treatment (not re‐treatment) during the 3‐year period. The data was derived from a prospective 3‐year longitudinal study in which the dental care provided by 41 dentists for 403 adolescents was monitored. Dental caries experience was monitored by annual standardised assessments of caries undertaken by a single trained examiner. ROC analysis showed that caries assessed visually at the D₁ threshold in 12‐year‐olds was a better predictor (P < 0.001) of experiencing some dentinal caries after 3 years (Az = 0.781) than was caries assessed visually at D₃ threshold in 12‐year‐olds (Az = 0.670). Assessing caries visually at either the D₁ or the D₃ threshold had no discriminatory power for predicting whether an individual would experience some restorative treatment during the ensuing 3‐year period (Az for D₁ = 0.507; Az for D₃ = 0.518).     

替牙(牙合)时期前牙反(牙合)矫治中弓丝弯制的探讨

目的　探讨在“2× 4”矫治技术中弓丝弯制的方法及原理。方法　替牙牙合时期前牙反牙合患者 2 4例 ,使用粗弓丝 ,在其弓丝上弯制各种曲形 ,并根据不同错牙合类型 ,处理各种曲与牙齿、带环关系 ,防止出现磨牙旋转移动等异常。结果　 2～ 6个月纠正反牙合 ,2 4例替牙牙合时期反牙合患者得以早期矫治。结论　本方法矫治时间短 ,效果明显 ,操作简单 ,能够达到较为理想的矫治效果     

Comparison of computer-assisted learning with tutorial teaching in a group of first-year dental students

Two identical groups of first-year dental students were instructed in the pathology of dental caries and periodontitis using computer-assisted learning (CAL) or tutorial teaching (TT). A cross-over arrangement, in which the first group was taught about dental caries by CAL and periodontitis by TT and the second group in the reverse order, allowed comparison of the two methods. The comparison included a knowledge test and completion of a questionnaire. CAL and TT were equally effective as far as acquisition of knowledge was concerned. Students felt pressurized with CAL and had problems with note-taking. They liked a teacher to be present. Nevertheless, CAL was an acceptable method of instruction and was more economical, in terms of staff involvement, than TT.     

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.