Third molar development in a London population of White British and Black British or other Black ethnicity

Population differences in dental development between Black and White ethnic groups have been debated but not previously studied in the UK. Using inappropriate data for dental age estimation (DAE) could lead to erroneous results and injustice. Data were collected from dental panoramic radiographs of 5590 subjects aged 6–24 years in a teaching hospital archive. Demirjian stages were determined for left-sided teeth and third molars and data collected regarding hypodontia and third molar agenesis. Third molar development in self-assigned Black British, including other self-assigned Black ethnicity, was compared with that of self-assigned White British subjects. Data were compared for males and females in the two ethnic groups using T-tests for Demirjian Stages A–G of third molar development and Mann-Whitney tests for Stage H once a cut-off age at the maximum age for Stage G had been imposed. Third molar development occurred earlier in subjects of Black ancestry compared to those of White ancestry. While both ethnic groups showed large age ranges for every third molar stage, in female subjects these generally occurred at least 1.5 years earlier, and in males at least one year earlier. Hypodontia and third molar agenesis were more prevalent in White British, but the ethnic difference in third molar development persisted in subjects with complete dentitions. This is a large study that confirms ethnic differences in a London population, emphasises the difficulties of establishing the 18-year-old threshold using DAE, and confirms the risk of overestimating the age of individuals of Black ethnicity using White ethnic reference data.     

Social inequalities without class cleavages in Latin America’s neoliberal era

Social inequalities have deepened in Latin America over the past several decades, yet an erosion of class cleavages has occurred in the political arena. During the era of import-substitution industrialization (ISI), “stratified” cleavage structures based on class distinctions emerged in a subset of Latin American countries where party systems were reconfigured by the rise of a mass-based, labor-mobilizing party. These nations typically experienced more severe economic crises during the transition from ISI to neoliberalism than nations that retained elitist party systems with “segmented,” cross-class cleavage structures. They also experienced greater political upheaval, as neoliberal critical junctures produced an erosion of stratified cleavages along their structural, organizational, and cultural dimensions in the labor-mobilizing cases, while leaving the segmented cleavages of elitist systems relatively unscathed. The Latin American experience differs from that of Europe, where strong labor movements and labor-backed parties were associated with superior economic performance during periods of economic adjustment. It also challenges Duverger's notion of an organizational “contagion from the Left,” as the dramatic weakening of labor movements and the shift away from mass-based party organizations have caused party systems to converge on elitist organizational models during the neoliberal era.     

Improving the quality and quantity of whole blood supply: limits to voluntary arrangements

The inadvertent transmission of AIDS virus through contaminated whole blood has shaken the viability of the American voluntary blood supply system. For the first time since the voluntary donor system replaced the commercial blood system, there are widespread doubts about the ability of blood suppliers to meet the nation's increasing health care demands. This paper presents a framework for analyzing blood collection. First, we critique the existing literature on blood collection, arguing that its focus on donor motivation is difficult to integrate with policy analysis. We then present a specific model of the individual's decision to donate blood as a comparison of the costs and benefits of donating. The current system of collecting whole blood relies on donors receiving only altruistic benefits. We explore the limits of this approach to dealing with the quantity and quality problems presented by the AIDS virus. Alternative approaches....