Microleakage in conservative cavities varying the preparation method and surface treatment

Objective

To assess microleakage in conservative class V cavities prepared with aluminum-oxide air abrasion or turbine and restored with self-etching or etch-and-rinse adhesive systems.

Material and Methods

Forty premolars were randomly assigned to 4 groups (I and II: air abrasion; III and IV: turbine) and class V cavities were prepared on the buccal surfaces. Conditioning approaches were: groups I/III - 37% phosphoric acid; groups II/IV -self-priming etchant (Tyrian-SPe). Cavities were restored with One Step Plus/Filtek Z250. After finishing, specimens were thermocycled, immersed in 50% silver nitrate, and serially sectioned. Microleakage at the occlusal and cervical interfaces was measured in mm and calculated by a software. Data were subjected to ANOVA and Tukey’s test (α=0.05).

Results

Forty premolars were randomly assigned to 4 groups (I and II: air abrasion; III and IV: turbine) and class V cavities were prepared on the buccal surfaces. Conditioning approaches were: groups I/III - 37% phosphoric acid; groups II/IV -self-priming etchant (Tyrian-SPe). Cavities were restored with One Step Plus/Filtek Z250. After finishing, specimens were thermocycled, immersed in 50% silver nitrate, and serially sectioned. Microleakage at the occlusal and cervical interfaces was measured in mm and calculated by a software. Data were subjected to ANOVA and Tukey’s test (α=0.05).

Conclusion

Marginal seal of cavities prepared with aluminum-oxide air abrasion was different from that of conventionally prepared cavities, and the etch-and-rinse system promoted higher marginal seal at both enamel and dentin margins.     

规范牙科高速手机消毒流程

目的旨在提高牙科高速手机使用寿命,降低医疗成本。方法规范各项操作流程,加强过程管理,做好保护措施。加强人员培训,提高工作人员的器械保护意识及成本控制观念。结果规范消毒流程后,牙科高速手机的维修率明显降低,延长了其使用寿命,降低了消耗成本。结论加强牙科高速手机的消毒过程管理,可延长器械使用寿命。     

150例骨科植入物可疑不良事件报告分析

目的对150例骨科植入物可疑不良事件报告进行分析,发现骨科植入物不良事件监测存在的问题,探讨解决问题的对策。方法采用回顾性研究方法,对近五年北京市药品不良反应监测中心收到的150例骨科植入物可疑不良事件报告进行综合分析。结果骨科植入物可疑不良事件报告数量占同期收到报告总数的10．6％,但远少于骨科植入物不良事件实际发生数量;不良事件关联性难以评价;报告质量有待提高。结论目前骨科植入物不良事件监测现状无法满足提取预警信号的要求。应在完善法律法规的基础上,不断提高报告的数量和质量,以加强信息利用度。     

Relationship between fluoride intake in Serbian children living in two areas with different natural levels of fluorides and occurrence of dental fluorosis

The amount of fluoride present naturally in drinking water is highly variable, being dependent upon the individual geological environment from which the water is obtained. Chronic exposure to exceeding fluoride doses induces set of toxic effects, i.e. fluorosis. The aim of this study was to examine fluoride content in water and in the most frequently used vegetables, potato and bean, grown in two different Serbian regions, i.e. control region (Valjevo) and high naturally occurring fluoride region (Vranjska Banja), and moreover, to correlate estimated daily intake with dental fluorosis occurrence as an adverse effect of fluoride exposure of schoolchildren in Serbia. Study confirmed significant difference in fluoride content in water, potato and bean, consumed by 12-year-old children in two investigated municipalities. Results of the study indicated positive and statistically significant correlation between daily intake of fluoride and dental fluorosis level in the fluorotic municipality of Vranjska Banja (r = 0.61; p = 0.000017). Obtained relationship could be evaluated by means of binary logistic regression analysis, whereas probability for fluorosis occurrence could be predicted using the following equation: fluorosis occurence (%) = (34.852 × C_water − 12.644 × C_potato − 9.362 × C_bean − 7.673) × 100 (Chi-Square (3) = 33.033; p < 0.001).     

Do childhood and adult socioeconomic circumstances influence health and physical function in middle-age?

This study examines the joint and separate contribution of social class in early and adult life to differences in health and physical function in middle-aged men. We use data from the Metropolit project which includes men born in 1953 in Copenhagen and a study of middle-aged Danish twins (MADT). In total 6292 Metropolit participants in a follow-up survey on health in 2004 were included in the study together with 2198 male twins of which 1294 were part of a male twin pair (N = 647 pairs). Logistic regression was used to investigate the association between social class in early and adult life, respectively and health in midlife, measured as limitations in running 100 m, poor dental status, poor self-rated health, and fatigue. In both datasets, men with low childhood or adult social class had a higher risk of being unable to run 100 m, having poor dental status, having poor self-rated health and fatigue than men from the highest social classes. When childhood and adult social class were mutually adjusted, the estimates for both measures were attenuated. Adjustment for living without a partner, body mass index (BMI) and smoking in midlife, which were also related to the four outcomes, had marginal effects on the estimates for childhood social class, but attenuated the effect of adult social class somewhat. Among male twin pairs discordant on adult social class, the twin in the lowest class seemed to be unable to run 100 m, rate own health poorer and being fatigued more often than the high class co-twin, while there seemed to be no twin pair difference in dental status. This suggests that the associations of adult social class with functional limitations, poor self-rated health and fatigue may partly be due to causal effects related to adult social class exposures, while social class differences in dental status might be consistent with an effect of factors mainly operating early in life.     

Relationships between daily total fluoride intake and dental fluorosis and dental caries

Objective:To explore the relationships between the daily total intake of fluoride,dental fluorosis and dental caries. Methods: An epidemiological method was used to investigate the daily total intake of fluoride,dental fluorosis,and dental caries among 236 and 290 children aged 8-13 years in a severe endemic area and in a non-fluorosis control area,respectively. The children were divided into eight subgroups according to each child’s estimated daily total intake of fluoride. The prevalence of dental fluoros...     

BEAUTIFUL FLOW流动型聚合瓷用于窝沟封闭术后3年临床效果观察

目的：观察BEAUTIFUL FLOW流动型聚合瓷用于第一恒磨牙窝沟封闭的临床效果。方法：7～8岁儿重120例480颗健康的第一恒磨牙分为2组：试验组用BEAUTIFUL FLOW流动型聚合瓷进行一侧窝沟封闭术,对照组用光固化窝沟封闭剂EstisealF作为自身对照。随访3年．结果：术后1、2、3年复查,试验组的封闭材料完全保留率分别为94．29％、87．50％、79．49％,对照组分别为86．19％、79．35％、69．25％,试验组术后1、2、3年的封闭材料完全保留率高于对照组,差异有统计学意义（P〈0．05）。术后1、2年龋病发生率差异无统计学意义（P〉0．05）,但术后3年试验组龋病发生率为1．92％,对照组为8．33％,差异有统计学意义（P〈0．05）.结论：BEAUTIFUL FLOW流动型聚合瓷是一种可靠的恒牙窝沟封闭材料．值得临床推广使用     

牙体解剖学实习教学改革初探

本文初步探讨了牙体解剖学实习教学的方法及其效果.通过引导思考、"强调目的"的教学方式,使学生由浅入深地积极思考各种操作目的、各种牙体解剖结构的作用,以及这些结构是如何与生理功能相互作用而实现其功能的,使学生养成"知其然更知其所以然"的习惯.这样,既有助于学生更加深入地理解牙体解剖结构的特点和作用,又能够将学生所掌握的解剖学理论知识引向口腔生理学等学科,初步建立口腔医学的学习思路.结果表明,上述教学方法的改革提高了教学质量,其效果得到了学生的肯定.     

Impact of Morbid Obesity on Chewing Ability

Background  This study compared the chewing parameters in a group of obese adult patients scheduled for gastric bypass surgery with those of a control group. Methods  Chewing parameters were measured in two groups of subjects, one of 44 obese patients scheduled for gastric bypass surgery (body mass index [BMI] = 49.1 ± 7.2) and the other of 30 non-obese control subjects (BMI = 20.9 ± 2.1). In both groups, the subjects’ dental status was characterized by the number of functional dental units. Kinematic parameters, namely chewing time (CT), number of chewing cycles (CC), and chewing frequency (CF), were video recorded during the mastication of five natural standardized foods (banana, apple, sweet jelly, peanut, and carrot). The particle size distribution of the expectorated bolus from carrot and peanuts was characterized by the 50th percentile (D ₅₀). Analysis was carried out to detect any effect of the fixed factors “dental status,” “type of food,” and “subject group” on the variations of the dependent factors CT, CC, CF, and D ₅₀. Results  In obese subjects, CT, CC, and D ₅₀ were variables depending on both dental status and food. For fully dentate subjects, the group of patients with obesity showed higher values for CT and CC and lower values for D ₅₀ for both carrot and peanuts than the control group. Conclusion  The chewing parameters were affected in fully dentate patients with morbid obesity compared with controls, emphasizing the need for a systematic evaluation of both dental status and chewing ability in patients scheduled for bariatric surgery.     

Tissue compatibility of biomaterials: benefits and problems of skin biointegration

The integration of biomaterials with skin is necessary to enable infection-free access to vasculature and body cavities. Also, integrating plastics and metals with skin increases options for the reconstruction of surgical and traumatic defects and enables the permanent implantation of robotic and electronic devices. Until now, attempts to integrate biomaterials with skin permanently have failed because of epidermal marsupialization and infection. This article reviews the general properties required of biomaterials to optimize integration with body tissues, the modifications that increase biocompatibility, focusing particularly on surface functionalization and the specific requirements for biomaterial integration into skin. Critical pathophysiological processes relating to biocompatibility are discussed with particular emphasis on the skin-biomaterial interface. Future directions are speculated on, in particular, the specific utility of subatmospheric pressure dressings in facilitating tissue integration into biomaterials.