An examination of the differential susceptibility pattern of the dentition to linear enamel hypoplasia

Jennifer S Nelson

doi:10.29173/comp49

Abstract

Enamel hypoplasia is a dental pathology that forms when an individual is exposed to physiological stress in early life while tooth crowns are developing. Biological anthropologists utilize these enamel defects as indicators of growth interruption and interpret them as reflective of factors pertaining to health status and cultural practices that influence health. Over decades of research, numerous studies have noted a pattern in the distribution of linear enamel hypoplasia across the dentition. It is suggested that the anterior dentition presents the highest frequency of defects, followed by the premolars, with molars most rarely exhibiting hypoplasia. This apparent differential susceptibility pattern has resulted in the preferential study of the anterior dentition in anthropology, however little research has been conducted into the validity or cause of this developmental phenomenon. Through examination of the literature, the observed higher frequency of enam2el hypoplasia in the anterior dentition substantiates the existence of this differential distribution pattern. Further investigation reveals that the cause of this varying susceptibility has not been sufficiently explored, leading to a number of inconclusive explanations. Examination of these theories – ranging from the chronology of tooth development, specifics of crown morphology, and variations in genetic control – indicate that there is no single causal variable, but that a multitude of factors are responsible. From this research it is apparent that further study is necessary to fully understand why the anterior teeth appear to be more susceptible to hypoplastic defects than their posterior counterparts.

Highlights

Enamel hypoplasia is a highly studied type of dental pathology that forms when an individual is exposed to physiological stress in early life while tooth crowns are developing
While a review of the literature substantiates a differential distribution pattern of higher LEH frequencies in the anterior dentition, the explanations for these findings presented in the surveyed literature are inconclusive
It is apparent from research into the aetiology of hypoplastic defects that, to the rest of the skeletal system, a multitude of factors are involved in the formation of tooth enamel

Summary

Introduction

Examination of various populations, researchers have noticed a pattern in the distribution of linear enamel hypoplasia across the dentition. The research on general hypoplasia in deciduous teeth has found that, while they have a lower frequency of defects than their permanent counterparts, they are still affected by hypoplasia of all types (Infante and Gillespie 1974; Jelliffe and Jelliffe 1971; Sweeney et al 1969) This differential susceptibility could be due to the more favourable and sheltered nature of the fetal environment during initial formation of these teeth, or a potentially higher resistance to enamel hypoplasia (Goodman and Rose 1990). It could be a product of the different enamel that forms deciduous tooth crowns, which is thinner and less mineralized than that of the permanent dentition, in addition to having a thicker and more uniform layer of prismless enamel at the crown surface (Oliveira et al 2010). Is done on the frequency of LEH in deciduous dentition, little can be concluded about their aetiology or prevalence

Literature Review

Summary

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Conclusion