Reduction of Dental Decay in Rampant Caries Individuals Following Short-Term Kanamycin Treatment

A week of kanamycin gel treatment before and after the placement of dental restorations, compared to a placebo gel treatment, significantly reduced the levels of cultivable bacteria, S mutans and S sanguis, in the plaque samples collected immediately after the completion of the gel treatments, and was associated with a 46% reduction in new carious surfaces in the 14- to 37-month period following the gel treatment.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68298/2/10.1177_00220345770560031101.pd

Relationship of Dental Caries and Fluorosis to Fluoride Supplement History in a Non-Fluoridated Sample of Schoolchildren

A random sample of 206 Michigan children, aged from 9 to 13, were examined for fluorosis from a larger group of 2038 children participating in a dental project. Clinical examinations included caries data (DMFS) and assessment of fluorosis by use of the Tooth Surface Index of Fluorosis (TSIF). Separate examiners were used for each index. The response rate of a questionnaire mailed to parents to gather information on residence histories, use of fluoride supplements, and antibiotics was 78%. The prevalence of fluorosis was about 20% among the respondents. Of the 4868 tooth surfaces examined, 9.2% were affected by fluorosis. In all cases, dental fluorosis was judged as mild, with most occurrences on the posterior teeth. No instances of moderate or severe fluorosis were found. The caries experience of respondents was 1.69 ± 2.73 DMFS. Caries experience does not appear to be significantly related to income, education, or fluoride supplement use. Approximately 52% of respondents were reported to have taken fluoride supplements with various degrees of consistency. Parents' education was positively related to both prevalence of fluorosis (odds ratio = 2.2) and use of fluoride supplements (odds ratio = 2.7). No significant relation was revealed with evidence of fluorosis and use of supplements. This study shows a relatively mild level of dental fluorosis in a sample of children from a non-fluoridated area. Dental fluorosis in this group does not appear to be related to use of fluoride supplements or differences in caries experience.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66503/2/10.1177_08959374890030021501.pd

An in Vitro Device for Evaluation of Cellular Response to Flows Found At the Apex of Arterial Bifurcations

Intracranial aneurysms (ICA) are abnormal dilations of the cerebral arteries, most commonly located at the apices of bifurcations. The ability of the arterial wall, particularly the endothelial cells forming the inner lining of the wall, to respond appropriately to hemodynamic stresses is critical to arterial health. ICA initiation is believed to be caused by a breakdown in this homeostatic mechanism leading to wall degradation. Due to the complex nature of this process, there is a need for both controlled in vitro and in vivo studies. Chung et al. developed an in vitro chamber for analyzing the response of biological cells to the hemodynamic wall shear stress fields generated by the impinging flows found at arterial bifurcations [6, 7]. Here, we build on this work and design an in vitro flow chamber that can be used to reproduce specific magnitudes of wall shear stress (WSS) and gradients of wall shear stress. Particular attention is given to reproducing spatial distributions of these functions that have been shown to induce pre-aneurysmal changes in vivo [38]. We introduce a measure of the gradient of the wall shear stress vector (WSSVG) which is appropriate for complex 3D flows and reduces to expected measures in simple 2D flows. The WSSVG is a scalar invariant and is therefore appropriate for use in constitutive equations for vessel remodeling in response to hemodynamic loads [34, 35]