Aetiological Factors for Developmental Defects of Enamel

Review Article

Austin J Anat. 2014;1(1): 1003.

Aetiological Factors for Developmental Defects of Enamel

Hai Ming Wong*

Department of Dentistry, University of Hong Kong, Hong Kong

*Corresponding author: Hai Ming Wong, Department of Dentistry, University of Hong Kong, The Prince Philip Dental Hospital, 34 Hospital Road, Hong Kong SAR.

Received: May 19, 2014; Accepted: May 21, 2014; Published: May 22, 2014

Abstract

Developmental defects of enamel remain as a permanent record of a disturbance during amelogenesis. They may present in different forms, some of which may be perceived by an individual as being disfiguring and so requiring treatment to improve the appearance of the teeth. The aim of this review is to address the aetiological factors for DDE because the knowledge is essential for clinicians when explaining and discussing the presence of DDE with patients and their parents. The possible aetiological factors for enamel defects in permanent teeth can be broadly divided into two main categories: those with a localized distribution and those with a generalized distribution. Amongst the causative agents of localized defects of enamel are trauma, localized infection and irradiation. Amongst the causative agents of generalized defects of enamel are genetic disorders and systemic disturbances including intoxications, perinatal and postnatal problems, malnutrition, infectious diseases and a range of other medical conditions. Most of the available data on the aetiology of enamel defects have been gained from animal studies and case reports of children with systemic disorders. The lack of robust data makes the results of these studies inconclusive.

Keywords: Developmental defects of enamel; Aetiological factors

Abbreviations

DDE: Developmental Defects of Enamel

Introduction

Tooth enamel is formed during only a certain period of the tooth development and is irreplaceable. Ameloblasts, which are secretory cells that produce dental enamel, are particularly sensitive to changes in their environment during the long process of enamel production. Dysfunction of ameloblasts may occur resulting in changes in the appearance of the enamel in the permanent dentition. These Developmental Defects of Enamel (DDE) may range from slight abnormalities of the tooth’s colour to a complete absence of the enamel.

Impacts of DDE

Effects of DDE may include tooth sensitivity or an increased risk of caries. Treatment of DDE attempts to improve the function and appearance of the affected teeth [1]. There is evidence that teeth with DDE have 10 times greater treatment need than normal teeth [2]. Apart from financial considerations of dental treatment, there is also the social cost including children’s absence from school and parents’ absence from work to attend multiple appointments. An affected individual may also experience low self–esteem or stigma because they perceive DDE as being disfiguring [3,4]. The knowledge of aetiological factors for DDE is essential for clinicians when explaining and discussing the presence of DDE with patients and their parents. Targeting risk factors could also assist in implementation of community strategies to limit the occurrence of DDE.

Terminology of DDE

An early report of enamel defects, according to Sarnat and Schour [5], appeared over 200 years ago when rickets, measles and scurvy were said to be associated with ‘erosion’ of the teeth. The term ‘mottled enamel’ was adopted by Black and McKay [6] to describe the appearance of teeth which they considered to represent an endemic form of the defect; it was not until 1931 that fluoride was identified as the causative agent of this defect [7]. The examples of the terminology that have been used in published studies to describe developmental defects of enamel are shown in Table 1 [5,6,8–20]. Some are simple descriptive clinical terms, while others are linked with the causative agent, or the histopathology of the defect. However, the majority of these terms are non–specific and frequently ambiguous. The terminology needs to be uniform to suit the requirements of the various investigators. Owing to the efforts of a working group of the Commission on Oral Health, Research and Epidemiology of the International Dental Federation (FDI), a standardized terminology,which accompanies the FDI (DDE) Index, has been established [21,22]. Based on the quality and quantity of affected enamel, DDE can be classified into three main types: demarcated opacities diffuse opacities and hypoplasia [22].