A comparison of DAI scores and characteristics of occlusal traits in three ethnic groups of Asian origin

Abstract

The Dental Aesthetic Index (DAI) is an orthodontic index based on socially defined aesthetic standards. The primary aim of this study was to compare the prevalence of malocclusion using the DAI among three ethnic groups of Asian origin; Japanese, Chinese in Taiwan and Native Americans with white Americans. A secondary goal was to consider the possibility that genetic factors might be the cause of the characteristics of malocclusion in the ethnic groups of Asian origin. Malocclusion was evaluated in 1029 Japanese and 176 Chinese in Taiwan students utilising the DAI, and the findings were compared with those of Native Americans and white Americans. The DAI values of Japanese and Native Americans were significantly higher than those of Chinese in Taiwan and white Americans. The mean DAI values showed no common tendency among the three ethnic groups. The characteristics of malocclusion in each ethnic group were also evaluated by analysis of each of the 10 DAI component scores. The results revealed common characteristics of malocclusion in the three ethnic groups of Asian origin using white Americans as the standard. The findings in the present study suggest the possibility that genetic factors might have an influence on the characteristics of malocclusion.

Orthodontic treatment need in a representative adult cohort

“…The results of other studies are limited by age limits and by restrictions to subpopulations such as students or army recruits. Because of discrepant measurement methods and basic socioeconomics, there are highly disparate views on the need for orthodontic treatment [9,16,18,21,22]. Thus comparison is only possible using a single index [21].…”

“…Die wenigen veröffentlichten Studien mit Beteiligung adulter Probanden befassen sich größtenteils mit ausgesuchten Subpopulationen wie Studenten oder Rekruten [5,18,24,28,30]. Die Ergebnisse dieser Untersuchungen sind nur eingeschränkt vergleichbar.…”

“…There are few published studies with adult volunteers, and these are mostly limited to specific subpopulations such as students or army recruits [5,18,24,28,30]. Their results are difficult to compare: the percentage of volunteers needing treatment depends heavily on the index and limit used, average ages, and ethnic origin.…”

Prevalência e severidade das alterações oclusais em escolares de 12 a 15 anos de Salvador - BA, 2004

“…Para o cálculo da amostra, foram usados os dados populacionais mais recentes disponí-veis da proporção de oclusopatias aos 12 anos de idade, descritos nos estudos nacionais (NARVAI et al, 2003;PERIN, 2002), considerando-se a representatividade para uma prevalência estimada de 10% na categoria de maior severidade do IED. O nível de significância adotado foi de 1%, e o poder do teste foi de 90%.…”

“…Poucos ainda são os trabalhos publicados que utilizam o IED no mundo (JENNY et al, 1991;ANSAI et al, 1993;ESTIOKO;WRIGHT;MORGAN, 1994;KATOH et al, 1998;OTUYEMI et al, 1999;JOHNSON;HARKNESS, 2000;ONYEASO, 2003), pois os autores têm encontrado diferentes necessidades de intervenção ortodôntica em diferentes locais, atribuindo-as a características étnicas de cada região, cuja influência é decisiva nas alterações oclusais.…”