Prevalence of enamel hypoplasia and isolated opacities in the primary dentition

PURPOSE: Enamel hypoplasia is of interest to both the clinician and the basic scientist because it may indicate an increased risk for caries and can contribute to the understanding of enamel development. The purpose of this paper is to report the prevalence of enamel hypoplasia and isolated enamel opacities in a cohort of healthy, well-nourished children in Iowa. METHODS: The study sample consisted of 698 children examined at 4-5 years of age. Individual tooth surfaces were scored for the presence of enamel hypoplasia (EH) and isolated enamel opacities. Prevalence of EH and isolated opacities were determined by tooth type and by gender. RESULTS: Six percent of the children examined had at least one tooth with EH; 27% had at least one tooth with isolated enamel opacities. There was no difference in the prevalence of EH between boys and girls, but significantly more boys than girls had enamel opacities. CONCLUSIONS: The prevalence of enamel defects in this study group is comparable to that seen in other studies of normally developed children except that in this study, the primary tooth types most commonly affected with enamel hypoplasia or isolated opacities were mandibular second molars and maxillary second molars, respectively.     

Longitudinal survey of enamel defects in a cohort of New Zealand children

Enamel defects are being used increasingly to monitor fluoride use. In New Zealand in 1982 a survey of the prevalence of enamel defects in 9-yr-old children was carried out. Children who had enamel defects on the labial surfaces of their maxillary incisors were re-examined after 3 yr together with an equal number of children without defects. The same examiner using the same examination methods and the DDE index carried out both examinations but at the second examination was unaware of the results for individual children at the first examination. There was little difference in the group prevalence of the main defect categories except for the tooth prevalence of hypoplasia. There was an increase in discolouration and hypoplasia occurring in combination with diffuse fluoride-related opacities. There was no evidence that defects had faded with time. This longitudinal survey showed that some increase in defect severity occurred over a relatively short time span in initially mild defects. In some children these changes were sufficient to cause a deterioration in tooth appearance. Age and tooth specific enamel defect data are necessary in surveys monitoring the public health use of fluoride since posteruptive changes can affect prevalence and severity.     

A detailed study of enamel hypoplasia in a post-medieval adolescent of known age and sex.

Developmental disturbances that affect the secretion of enamel matrix can cause defective enamel structure. Linear hypoplasia is one type of enamel defect and manifests itself as a furrow that runs around the circumference of the tooth. Such defects range in size from the microscopic to those that are several millimetres wide. Enamel defects have been widely used by anthropologists for the investigation of growth disruptions in past populations, as they provide a permanent record of disturbances during much of a child's developmental period. This is a detailed case study of enamel growth disruptions in a 15-year-old female from the 18th and 19th century crypt of Christ Church, Spitalfields. The method used relates linear enamel hypoplasia to the incremental structures in the enamel surface, the perikymata, in order to investigate the timing of growth disturbances. Linear enamel hypoplasia was defined here as a greater than expected spacing between neighbouring pairs of perikymata. In addition, this study used recently published histological data on the precise timing of tooth development to establish chronologies for growth disruptions. Defects were matched in at least two teeth with overlapping developmental schedules to ensure that systemic disturbances, as opposed to localised traumas, were identified. Thirteen enamel defects were matched between five different teeth from the same individual from Spitalfields. Most linear enamel hypoplasias were evident on the anterior dentition. Using an 8-day average perikymata periodicity, the age at first defect in this individual was calculated as 1.5 years and the last growth disruption occurred when she was 4.6 years of age. The distribution of the defects was examined to identify any seasonal pattern in the occurrence of the growth disturbances.     

Clinical and microstructural aberrations of enamel of deciduous and permanent teeth in patients with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy

Objective

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) causes multiple endocrine deficiencies, oral candidiasis and different forms of ectodermal dystrophy including enamel hypoplasia, documented in permanent teeth. Our purpose was to examine dental aberrations associated with APECED, including possible manifestations in primary teeth.

Design

We studied clinically, radiographically, and by scanning electron microscopy (SEM) teeth of children belonging to two APECED families with different mutations in the AIRE gene.

Results

In addition to enamel defects in the permanent teeth we observed hypoplastic pits and hypomaturated patches in the deciduous teeth with underlying changes in the prismatic ultrastructure. The enamel of the permanent molars exhibited a layered arrangement with included whirl-like formations.

Conclusions

Our findings confirm that APECED causes enamel defects that are individually but chronologically distributed, and can alter enamel development early enough to affect deciduous teeth.     

Clinical and microstructural aberrations of enamel of deciduous and permanent teeth in patients with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy

Objective

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) causes multiple endocrine deficiencies, oral candidiasis and different forms of ectodermal dystrophy including enamel hypoplasia, documented in permanent teeth. Our purpose was to examine dental aberrations associated with APECED, including possible manifestations in primary teeth.

Design

We studied clinically, radiographically, and by scanning electron microscopy (SEM) teeth of children belonging to two APECED families with different mutations in the AIRE gene.

Results

In addition to enamel defects in the permanent teeth we observed hypoplastic pits and hypomaturated patches in the deciduous teeth with underlying changes in the prismatic ultrastructure. The enamel of the permanent molars exhibited a layered arrangement with included whirl-like formations.

Conclusions

Our findings confirm that APECED causes enamel defects that are individually but chronologically distributed, and can alter enamel development early enough to affect deciduous teeth.     

Comparison of methods for measurement of hypoplastic lesions

Enamel hypoplasia is a quantitative defect of enamel thickness. Methods previously used for its measurement have limitations in clinical studies. The aim of this study was to investigate new methods of measurement using image analysis. Lesions on 8 teeth affected by enamel hypoplasia were quantified from study models and impression surfaces using an image-analysis system. The measurements made included lesion area and tooth surface area; from these the proportion of tooth surface area affected was calculated. For comparison, manual measurement was performed on impression surfaces and study models, using digital callipers. Images were also acquired of lesions on 12 exfoliated teeth, and the lesion area and total tooth area were calculated. For assessment of intra-operator reliability, the +/– repeatability coefficient was calculated. Measurement of the surface of lesions direct from the exfoliated teeth gave the best results overall, followed by direct image analysis of the silicone impression.     

Abrasion, erosion, and abfraction combined with linear enamel hypoplasia: a case report.

Linear enamel hypoplasia is a developmental disturbance of enamel resulting in clinically visible horizontal defects in enamel that are present on eruption of the tooth. Nondevelopmental lesions of the hard tissues of the tooth, including carious, abrasion, erosion, attrition, and abfraction lesions, require varying amounts of time after tooth eruption to develop. Because linear enamel hypoplasia lesions are present on eruption and are exposed to the factors responsible for abrasion, erosion, and abfraction, nondevelopmental lesions could occur within them in any combination. This report describes a patient with multiple teeth with linear enamel hypoplasia lesions containing nondevelopmental defects as well as nondevelopmental defects that occurred separately. Severe pain and a unique lesion morphology were associated with the linear enamel hypoplasia defects. Affected teeth were extracted because of advanced periodontitis and were sectioned to determine the nature of the enamel and dentin lesions.     

前牙超薄瓷贴面美学修复32例临床疗效观察

目的：评价超薄瓷贴面前牙美容修复的临床效果。方法：因四环素牙、氟斑牙、牙釉质发育不全、牙间隙过大、牙齿缺损、增龄性变黄等原因需行前牙美容修复的患者32例,108颗牙,用超薄热压铸瓷贴面进行修复。术后1、6、12、24、36个月,按照美国公共健康协会的修正标准（USPHS）进行评估。结果：经过3年的临床观察,108颗瓷贴面中有2颗折裂,修复体成功率98．1％。吸烟患者的边缘着色率明显高于不吸烟患者。结论：超薄热压铸造瓷贴面具有磨除牙体组织少、瓷贴面修复体强度高等特点,具有良好的临床修复效果。     

Developmental enamel defects in the primary dentition: aetiology and clinical management

Developmental enamel defects, presenting as enamel hypoplasia or opacities are caused by damage or disruption to the developing enamel organ as a result of inherited and acquired systemic conditions. The high prevalence of these defects in the primary dentition demonstrates the vulnerability of the teeth to changes in the pre‐ and postnatal environment. The presence of enamel hypoplasia increases the risk of primary teeth to early childhood caries and tooth wear as the defective enamel is thinner, more plaque retentive and less resistant to dissolution in acid compared to normal enamel. The purpose of this paper was to critically review the aetiology and clinical complications of developmental enamel defects in the primary dentition and propose recommendations for the clinical management of affected teeth.     

Association between developmental defects of enamel and dental caries in schoolchildren

Despite improvement, dental caries is still the main public oral health problem worldwide and the major cause of pain, tooth loss and chewing difficulties in children and adolescents; and it impacts negatively on oral health-related quality of life. A cross-sectional study of a multistage representative sample of 8–12-year-old Brazilian school children was carried out in order to investigate the association between enamel defects and dental caries. Children's mothers completed a questionnaire about socio-demographic and behavioural characteristics at home. Firth's bias reduced logistic regression models were undertaken to assess the association between the main exposure (enamel defects) and caries experience. The prevalence of any enamel defect was 64.0%; the prevalence of diffuse opacities, demarcated opacities and enamel hypoplasia was 35.0%, 29.5% and 3.7%, respectively. The prevalence of dental caries was 32.4%, with mean DMFT of 0.6 (SD, 1.2). Dental caries experience was more common among children who had enamel hypoplasia in their posterior teeth (OR = 2.79; 95% CI: 1.05, 6.51) than among those with none. In anterior teeth, there was no association. Enamel hypoplasia appears to be an important risk factor for dental caries.     

Traumatic injuries to the primary dentition and effects on the permanent successors – a clinical follow-up study

Abstract –  This study investigated problems in the permanent dentition that, according to history and records, were attributable to dental alveolar injuries of the primary dentition. 106 children have been involved in the study, who had experienced primary anterior tooth trauma affecting a total of 200 teeth. Thirty-nine patients (81 teeth) were available for follow-up examinations. In 25% of the cases followed up, damage was found on the successors in the secondary dentition (16 children/20 teeth). In half of the cases, a comparatively mild form of lesion like enamel discoloration was observed. This was the result of an injury during the tooth maturation process causing enamel hypoplasia. Clinically more relevant were the dental deformities: cessation of root formation or retention caused by ankylosis, which made up the remaining 50% of cases. This was confirmed by clinical long-term observation. The different effects on the permanent teeth can only be detected by radiography after an interval of several months or may even be clinically assessed only after the eruption of the clinical crown.     

Changes in the dental hard tissues and supporting structures in tetanic syndrome. I. Review of the literature]

The authors give a survey of the literature on the tetanic syndrome and its effects on the dental hard tissues and the tooth supporting structures. In cases of normocalcaemic tetany, no pathological alterations have been observed in the dental hard tissues, the pulp and the periodontium. On the contrary, enamel hypoplasia, broad pulp chambers, shortened tooth rootsdelayed dentition, hypodontia, inflammatory changes and bleedings from the periodontal ligament, bone densification and chronic gingivitis have been found in patients with hypocalcaemic tetany.     

乳牙釉质发育不全的组织学研究

本研究运用偏光显微镜和显微放射照相技术对发育不全乳牙的组织学特征进行分析,发现釉质发育不全乳牙的新生线表现为低矿化的窄带状,病损发生于生后釉质,病损底多与新生线相吻合,病损内可见不同程度的矿化不良区域。得出:釉质发育不全不仅有釉质量的减少,而且有质的改变。后者可能增加了釉质发育不全牙齿对龋的易感性。     

Predictors of variation in mandibular incisor enamel thickness

BACKGROUND: Interproximal reduction of mandibular incisor enamel often is performed as an adjunct to orthodontic alignment. The authors conducted a study to determine factors contributing to variations in incisor enamel thickness. METHODS: The authors compared enamel thickness between mandibular central and lateral incisors, between mesial and distal surfaces, between male and female subjects (N=40 each) and between African-American and white subjects (N=40 each). The authors also evaluated correlations between overall tooth width and enamel thickness. RESULTS: The authors found significantly greater enamel thickness in lateral incisors, on distal tooth surfaces and in black subjects (P<.0001 for each); they found no differences between male and female subjects. They found that wider teeth were associated with greater enamel thickness (P<.01) but that the amount of thickness varied greatly among subjects (range: 0.44-1.28 millimeters). CONCLUSIONS: Thicker enamel was found on the distal aspect of lateral incisors, in black subjects and in wider teeth. The authors observed, however, that the variations in thickness are not fully explained by these factors alone. CLINICAL IMPLICATIONS: If substantial enamel reduction is planned as part of dental treatment, the authors recommend that clinicians use calibrated radiographs to measure the thickness of their patients' enamel surfaces because of the extensive variation in enamel thickness among and within people.     

Tooth erosion caused by chewing aspirin

BACKGROUND: Although the effects of aspirin on the oral mucosa are well-documented, there is little documentation of the effects of aspirin-chewing on the enamel and dentin. CASE DESCRIPTION: The authors present two cases of patients with damage to their tooth enamel and dentin. Both patients had similiar symptoms, but had not been told that chewing aspirin could harm tooth structure. The authors identify clinical signs and symptoms and discuss ways to prevent erosion. CLINICAL IMPLICATIONS: The common factor in these cases is that aspirin was the only possible cause of the tooth erosion. Dentists should be aware of the effects of aspirin-chewing on tooth structure and advise their patients accordingly.     

Macroscopic and scanning electron microscopic appearance and hardness values of developmental defects in human permanent tooth enamel

Defects present in 12 human permanent teeth were classified on the basis of their macroscopic appearance as hypoplasia (three teeth), diffuse opacities (three teeth), white demarcated opacities (one tooth but two defects), or yellow demarcated opacities (five teeth but six defects). The hardness values and SEM appearance of the defective enamel were determined after the teeth were sectioned through the lesion(s) and were distinctive for each type of defect. The thin enamel of the hypoplastic lesions was either opaque (with reduced hardness values) or translucent (with near-normal hardness values and sometimes a change in prism orientation external to an incremental line). The enamel of the diffuse and demarcated opacities was of normal thickness. The changes in the macroscopic and SEM appearance, and the reduced hardness values of the diffuse patchy opacities, were restricted to the outer 150 microns of the enamel. The demarcated opacities varied in position and depth, and in places had a clearly marked boundary with the adjacent normal enamel. Hardness values were related to color change, with yellow lesions being softer than white. Although prism direction was normal within demarcated opacities, prism outlines were less distinct. The findings suggest that temporary and permanent dysfunction of ameloblasts can occur in both secretory and maturation phases, influencing the final appearance of the lesion.     

Developmental defects of enamel in Chinese girls and boys in Hong Kong

The FDI (DDE) Index--with some modifications and a re-designed recording sheet--was used to determine the prevalence of the different types of developmental defects of enamel. The public water supply contained 1.0 ppm when the children were bron and 0.7 ppm at the time of the examinations. All surfaces of the teeth of 460 female and 484 male, 12-year-old, Chinese children were examined after the teeth had been cleaned and dried. Mouth prevalences for all types of opacities, hypoplasia, and discoloration were 99.6%, 82.8%, and 16.6%, respectively. There was no apparent statistically significant difference between girls and boys. However, a statistically significant difference was seen between the sexes for white patches (p less than 0.05), missing enamel (p less than 0.05), and horizontal grooves (p less than 0.01). There were 811 (85.7%) children with more than 13 teeth affected by opacities, and 417 (44.2%) children had more than four teeth affected by hypoplasia. The most common defect was the diffuse white patch, and the least common was the vertical groove. There were 189 (39.0%) boys with between four and 12 teeth affected by more than two types of defect per tooth. White lines were the most difficult defect to diagnose reproducibly. Intra-examiner reproducibility for all other defects achieved levels of "almost perfect" and "substantial" by calculation of the Kappa coefficient.     

The chemical composition of tooth enamel in junctional epidermolysis bullosa

The junctionalis form of epidermolysis bullosa (EBJ) is associated with a number of clinical problems involving tooth enamel, including increased susceptibility to caries. The aim here was to carry out a chemical characterization of the enamel of teeth from EBJ patients compared with that of unaffected controls. The results showed that while protein concentration, amino acid composition and carbonate content were similar in both groups, EBJ enamel contained a significantly reduced mineral per volume content, resulting in enamel hypoplasia. In addition, Western blotting revealed the presence of serum albumin (a known inhibitor of enamel crystal growth) in EBJ enamel. This was not detected in control enamel or in enamel of teeth from patients with the dystrophic form of the disease. It is concluded that EBJ enamel is developmentally compromised and that the enamel defects are commensurate with the reported genetic lesions.     

Oral alterations in patients with cystinosis

Cystinosis is a rare autosomal recessive lysosomal storage disorder, which leads to abnormal accumulation of cysteine in various organs, including progressive dysfunction of kidneys. The most severe and frequent form, affecting ～95% of patients, is termed infantile nephropathic cystinosis (NC) (OMIM 219800). We have reported oral findings in two patients with NC and described esthetic and functional rehabilitation in one of them. The first case describes a 16‐year‐old male patient, who was diagnosed with NC when he was 1‐year‐old. The patient exhibited generalized enamel hypoplasia, grade 1 drug‐induced gingival overgrowth, caries lesion in molar tooth and supernumerary tooth (ie, distomolar). The second case describes a 14‐year‐old male patient diagnosed with NC at 3 years old. Clinical examination revealed generalized enamel hypoplasia and grade 1 drug‐induced gingival overgrowth. Radiographic examination showed supernumerary tooth (mesiodens). The treatment included gingivoplasty and restoration with direct composite resin. The severity of hypoplasia highlights the importance of a dental rehabilitation treatment, as proposed here. Direct restoration with composite resin allowed harmony, function, and esthetics to be restored, in addition to being a rapid and low‐cost technique.