Association between molar hypomineralization, genes involved in enamel development, and medication in early childhood: A preliminary study.

BACKGROUND: Molar hypomineralization (MH) is defined as a multifactorial condition, and thus, its presence may be defined by interactions between environmental and genetic factors. AIM: To evaluate the association between MH, genes involved in enamel development, and the use of medication during pregnancy in early childhood. DESIGN: One hundred and eighteen children, 54 with and 64 without MH, were studied. The data collected included demographics, socioeconomic data, and the medical history of mothers and children. Genomic DNA was collected from saliva. Genetic polymorphisms in ameloblastin (AMBN; rs4694075), enamelin (ENAM; rs3796704, rs7664896), and kallikrein (KLK4; rs2235091) were evaluated. These genes were analyzed by real-time polymerase chain reaction using TaqMan chemistry. The software PLINK was used to compare allele and genotype distributions of the groups and to assess the interaction between environmental variables and genotypes (p < .05). RESULTS: The variant allele KLK4 rs2235091 was associated with MH in some children (odds ratio [OR]: 3.75; 95% confidence interval [CI] = 1.65-7.81; p = .001). Taking medications in the first 4 years of life was also associated with MH (OR: 2.94; 95% CI = 1.02-6.04; p = .041) and specifically in association with polymorphisms in ENAM, AMBN, and KLK4 (p < .05). The use of medications during pregnancy was not associated with MH (OR: 1.37; 95% CI = 0.593-3.18; p = .458). CONCLUSION: The results of this study suggest that taking medication in the postnatal period appears to contribute to the etiology of MH in some evaluated children. There may be a possible genetic influence of polymorphisms in the KLK4 gene with this condition.

Prenatal, neonatal and postnatal factors and the developmental defects of dental enamel / Fatores pré-natais, neonatais e pós-natais e defeitos de desenvolvimento do esmalte dentário

ABSTRACT Objective: To estimate the prevalence of developmental defects in dental enamel and its possible association with prenatal, neonatal and postnatal conditions in six-year-old schoolchildren in a southern Brazilian municipality. Methods: A cross-sectional study was conducted involving 655 six-year-old schoolchildren. Sociodemographic and health data were collected through interviews with mothers and children's oral examinations at schools. Multivariate analyses were performed using Poisson regression with robust estimator. Results: The prevalence of developmental defects of enamel was 44.0%. Demarcated opacities were the most prevalent, followed by diffuse opacities. Late pregnancy, maternal schooling less than eight years, female gender and child's white skin color were independently associated with the prevalence of demarcated opacities. Conclusions: The prevalence of developmental defects in dental enamel was 44.0%. Late pregnancy, maternal schooling less than eight years, female gender and child's white skin color were associated with the prevalences.

RESUMO Objetivo: Estimar a prevalência de defeitos de desenvolvimento do esmalte dentário e sua possível associação com fatores pré-natais, neonatais e pós-natais em escolares de seis anos de idade em um município do sul do Brasil. Métodos: Foi conduzido um estudo transversal envolvendo 655 escolares de seis anos de idade. Os dados sociodemográficos e de saúde foram coletados por meio de entrevistas com as mães e exames bucais das crianças nas escolas. As análises multivariadas foram realizadas por meio de regressão de Poisson com estimador robusto. Resultados: A prevalência de defeitos de desenvolvimento do esmalte foi de 44,0%. As opacidades demarcadas foram as mais prevalentes, seguidas das difusas. Gravidez tardia, escolaridade materna inferior a oito anos, sexo feminino e cor da pele branca da criança foram independentemente associados à prevalência de opacidades demarcadas. Conclusões: A prevalência de defeitos de desenvolvimento do esmalte dentário foi de 44,0%. Gravidez tardia, escolaridade materna inferior a oito anos de estudo, sexo feminino e cor da pele branca da criança estiveram associados às prevalências.

Defeitos de desenvolvimento de esmalte, cárie dentária e impacto na qualidade de vida de crianças e adolescentes com doença renal crônica: um estudo transversal pareado / Developmental defects of enamel, dental caries and impact on the children and adolescents quality of life with chronic kidney disease: a paired cross-sectional study

A doença renal crônica (DRC) é uma alteração clínica resultante de lesão renal irreversível que persiste por um período igual ou superior a três meses. As implicações bucais clássicas da DRC incluem doença periodontal e xerostomia, enquanto a prevalência de cárie dentária e defeitos de desenvolvimento de esmalte (DDE) é controversa. A percepção de crianças e adolescentes com DRC sobre sua qualidade de vida relacionada a saúde geral (QVRS) e bucal (QVRSB) também é pouco explorada na literatura. Assim, o objetivo do presente estudo foi analisar a prevalência de DDE e da cárie dentária e comparar as variáveis sociodemográficas, relacionadas à saúde, gestacionais, clínicas bucais e o impacto na QVRS e QVRSB de crianças e adolescentes com e sem DRC. Para tal, foi realizado um estudo transversal pareado na proporção de 1:2 com uma amostra de 81 participantes de 5 a 18 anos pareados por idade e sexo. Foram excluídos participantes com tratamento ortodôntico, síndromes, alterações sistêmicas, neurológicas ou oncológicas. A coleta de dados incluiu aplicação de questionários sobre saúde dos participantes, aspectos sociodemográficos, histórico gestacional e mensuração da qualidade de vida utilizando o PedsQL™ e PedsQL™-OH. Os participantes foram submetidos a exame clínico bucal para detecção de cárie dentária (ICDAS) e suas consequências pulpares (pufa/PUFA), DDE (DDE modificado) e traumatismo dentário (índice de Andreasen) por um examinador previamente treinado e calibrado (Kappa >0,90). A análise dos dados foi conduzida pelo programa SPSS 23.0 e incluiu análise de frequência, teste de normalidade de Shapiro-Wilk, análises bivariadas com teste Qui-Quadrado, teste exato de Fisher e Teste de Mann-Whitney, além de regressão de Poisson ajustada e não ajustada (RP, IC=95%, p<0,05). Participaram do estudo 27 crianças/adolescentes com DRC e 54 sem DRC. Nas análises bivariadas, os resultados dos escores médios da QVRS obtidos pelo PedsQL™ indicaram que as crianças/adolescentes com DRC, bem como seus pais/responsáveis, apresentaram piores percepções da QVRS (p= 0,012). Os domínios mais afetados no grupo com DRC, em comparação ao controle, foram as "atividades escolares" e "aspectos psicossociais". O grupo com DRC também apresentou piores percepções da QVRSB, especialmente nos domínios de "sensibilidade dentária" e "dentes escuros". A DRC também esteve associada a prematuridade (p=0,006), uso de medicamento (p<0,001), hospitalização (p<0,001), maior média de dentes com DDE (5,22 vs. 2,89; p=0,002) e menor média de dentes cariados (0,40 vs. 5,07; p<0,001). Na análise multivariada final, observou-se que crianças/adolescentes com DRC apresentaram 78% maior prevalência de uso de medicamentos (RP: 1,78; IC 95%: 1,42-2,23), 22% maior prevalência de ocorrência de prematuridade (RP: 1,22; IC 95%: 1,03-1,44) e 2% menor prevalência de média de dentes cariados (RP: 0,98; IC 95%: 0,96-0,99). Conclui-se que crianças/adolescentes com DRC apresentam maior ocorrência de prematuridade, maior uso de medicamentos, menor média de dentes cariados e percebem sua QVRS e QVRSB com escores mais baixos em comparação aos indivíduos sem DRC, ressaltando a importância de abordagens multidisciplinares que considerem o bem-estar físico e psicossocial desses pacientes. Assim, compreender as necessidades e impacto na QVRS/QVRSB de crianças/adolescentes com DRC é essencial para políticas públicas e cuidados personalizados.

Chronic kidney disease (CKD) is a clinical condition resulting from irreversible kidney damage that persists for three months or longer. The classic oral implications of CKD include periodontal disease and xerostomia, while the prevalence of dental caries and developmental enamel defects (DDE) remains controversial. The perception of children and adolescents with CKD regarding their quality of life related to general health (HRQoL) and oral health (OHRQoL) is also underexplored in the literature. Therefore, the aim of this study was to analyze the prevalence of DDE and dental caries and to compare sociodemographic, health-related, gestational, and oral clinical variables, as well as the impact on HRQoL and OHRQoL between children and adolescents with and without CKD. A matched cross-sectional study was conducted with a sample of 81 participants aged 5 to 18 years, matched by age and sex in a 1:2 ratio. Participants undergoing orthodontic treatment or those with syndromes, systemic, neurological, or oncological conditions were excluded. Data collection included administering questionnaires on participants' health, sociodemographic aspects, gestational history, and measuring quality of life using PedsQL™ and PedsQL™-OH. Participants underwent an oral clinical examination to detect dental caries (ICDAS) and its pulp consequences (pufa/PUFA), DDE (modified DDE), and dental trauma (Andreasen index) by a trained and calibrated examiner (Kappa >0.90). Data analysis was conducted using SPSS 23.0 and included frequency analysis, Shapiro-Wilk normality test, bivariate analyses with Chi-Square test, Fisher's exact test, and Mann-Whitney test, in addition to adjusted and unadjusted Poisson regression (PR, 95% CI, p<0.05). The study included 27 children/adolescents with CKD and 54 without CKD. In the bivariate analyses, the mean HRQoL scores obtained by PedsQL™ indicated that children/adolescents with CKD, as well as their parents/guardians, had worse perceptions of HRQoL (p= 0.012). The domains most affected in the CKD group compared to the control group were "school activities" and "psychosocial aspects." The CKD group also had worse perceptions of OHRQoL, particularly in the domains of "dental sensitivity" and "dark teeth." CKD was also associated with prematurity (p=0.006), medication use (p<0.001), hospitalization (p<0.001), a higher mean number of teeth with DDE (5.22 vs. 2.89; p=0.002), and a lower mean number of decayed teeth (0.40 vs. 5.07; p<0.001). In the final multivariate analysis, it was observed that children/adolescents with CKD had a 78% higher prevalence of medication use (PR: 1.78; 95% CI: 1.42-2.23), a 22% higher prevalence of prematurity (PR: 1.22; 95% CI: 1.03-1.44), and a 2% lower prevalence of the mean number of decayed teeth (PR: 0.98; 95% CI: 0.96-0.99). It is concluded that children/adolescents with CKD have a higher occurrence of prematurity, higher medication use, a lower mean number of decayed teeth, and perceive their HRQoL and OHRQoL with lower scores, highlighting the importance of multidisciplinary approaches. Thus, understanding the needs and impact on HRQoL/OHRQoL of children/adolescents with CKD is essential for public policies and personalized care.

O impacto dos defeitos de esmalte no planejamento ortodôntico / The impact of enamel defects on orthodontic planning

Resumo A decisão pela extração de dentes permanentes para a solução de problemas ortodônticos considera, além da extração em si, outros fatores, dentre eles, as características clínicas do esmalte dos dentes a serem extraídos. O objetivo deste artigo foi apresentar como a presença de defeitos de esmalte dentário (DDE) influenciou na tomada de decisão e modificou o plano de tratamento ortodôntico proposto para o paciente. A severidade do defeito, o número de dentes afetados e a presença e complexidade de má oclusão são fatores que influenciaram na definição do plano de tratamento. Quanto mais grave os defeitos e mais complexa a má oclusão, maior a dificuldade no planejamento do tratamento e, em muitos casos, é indicado incorporar a contribuição de vários especialistas na tomada de decisões. Foi possível demonstrar que o tratamento da má oclusão associada a DDE com a exodontia dos dentes mais severamente afetados apresentou resultados estético e funcional adequados. Concluiu-se que um tratamento bem-sucedido da má oclusão com resultado estético dentofacial adequado, saudável e funcional, requer a compreensão da inter-relação entre os componentes estruturais bucais, oclusão dentária e estética facial.(AU)

Abstract The decision to extract permanent teeth to solve orthodontic problems considers, in addition to the extraction itself, other factors, and among them are the clinical characteristics of the enamel of the teeth to be extracted. The objective of this article was to present how the presence of dental enamel defects (DED) influenced decision-making and modified the proposed orthodontic treatment plan for the patient. The severity of the defect, the number of affected teeth and the presence and complexity of the malocclusion are factors that influenced the definition of the treatment plan. The more severe the defects and the more complex the malocclusion, the greater the difficulty in planning the treatment and, in many cases, it is indicated to incorporate the contribution of several specialists in the decision-making process. It was possible to demonstrate that the treatment of malocclusion associated with DED with the extraction of the most severely affected teeth, presented adequate aesthetic and functional results. It is concluded that a successful treatment of malocclusion with adequate, healthy, and functional dentofacial aesthetic results, requires understanding the interrelationship between oral structural components, dental occlusion and facial aesthetics. (AU)

Association between developmental defects of enamel and early childhood caries in children under 6 years old: A systematic review and meta-analysis.

Early childhood caries (ECC) are an oral health problem worldwide in children under 6 years of age. This disease of rapid development has a multifactorial etiology, and one of the possible risk factors is developmental defects of enamel (DDE), such as hypoplasia and opacities. The aim of this systematic review was to evaluate the association between DDE and ECC in children under 6 years of age. An electronic search was conducted until March 2022 using Medline (PubMed), Scopus, Science-Direct, LILACS, Web of Science, Cochrane Library, EBSCO-Host, EMBASE, and Google Scholar and complemented with a manual search, with no restrictions on language or date of publication. Longitudinal studies of children under 6 years of age with primary dentition were included. A total of 1158 studies were found, of which 651 records were reviewed by title and abstract, and 24 articles were selected for full-text evaluation. Finally, nine studies that met the selection criteria were included in the qualitative synthesis. Study quality and certainty were assessed using the Newcastle-Ottawa scale and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool. Three cohort studies of good quality were included in the meta-analysis. A risk associated with DDE (RR = 1.94; 95% CI: 1.52-2.49) and a risk associated with enamel hypoplasia (RR = 5.45; 95% CI: 1.84-16.14) were found. The results for diffuse opacity (RR = 1.21; 95% CI: 0.18-8.15) and demarcated opacity (RR = 1.26; 95% CI: 0.43-3.65) were not significant. GRADE analysis presented low and very low certainty of evidence. It was concluded that there is an association between DDE and ECC. However, the results should be interpreted with caution because of the limitations of the study. The protocol for this study has been registered in PROSPERO under identification number CRD42021238919.

A Recurrent FAM83H Mutation in an Extended Colombian Family and Variable Craniofacial Phenotypes.

Amelogenesis imperfecta (AI) is a collection of rare genetic disorders affecting the quantity and/or quality of the tooth enamel. AI can be classified into three major types according to the clinical phenotype: hypoplastic, hypocalcified, and hypomatured. Among them, the hypocalcified type shows the weakest physical properties, leaving rough and discolored enamel surfaces after tooth eruption. To date, mutations in the FAM83H gene are responsible for the autosomal-dominant hypocalcified AI. In this study, we recruited a four-generation Colombian family with hypocalcified AI and identified a recurrent nonsense mutation in the FAM83H gene (NM_198488.5:c.1289C>A, p.(Ser430 *)) by candidate gene sequencing. Cephalometric analyses revealed the anterior open bite that occurred in the proband is not correlated with the AI in this family.

Association between asthma and enamel defects in primary and young permanent teeth - A systematic review.

Childhood respiratory diseases, such as asthma, are important public health problems worldwide and could be associated with tooth enamel defects. This study aimed to verify the relationship between asthma and enamel defects in teeth, to answer the following question: "Could asthma in children be significantly associated with enamel defects in deciduous dentition and young permanent teeth?." PUBMED-MEDLINE, EMBASE, LILACS, and COCHRANE databases were systematically searched and assessed articles (2000-2021) were cautiously scored according to a predetermined criterion. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses were considered. Twenty-two articles were critically appraised and used as a basis for conclusions. The relationship between asthma and enamel defects was confirmed in the majority of appraised papers, one with a high level of evidence, nine with a moderate level, and four with a low level. Out of the eight manuscripts investigating the influence of asthma medication on enamel defects, only three (one with high, one moderate, and another with a low level of evidence) suggested an association. It can be concluded that asthma is closely connected with enamel defects in young permanent teeth. However, as most of the papers appraised were of cross-sectional or case-control design, further well-designed clinical investigations with a prospective design are welcome to reinforce our findings.

Molar incisor hypomineralization (MIH): prevalence and degree of severity in a Mexican pediatric population living in an endemic fluorosis area.

OBJECTIVE: To estimate the prevalence and severity of molar incisor hypomineralization (MIH) in 8 years old children living in an endemic fluorosis area. METHODS: MIH prevalence rate was determined from a study sample comprising 613 participants. They were recruited from 11 urban public schools with similar socio-economic status. Oral evaluations were performed and diagnosed MIH teeth were classified under Ghanim et al.'s criteria. Statistical descriptive and comparative analyzes were carried out. RESULTS: First permanent molars were the tooth group most affected, followed by the upper central incisors, lower central incisors, lower lateral incisors, and upper lateral incisors. There was no significant statistical difference by gender and by maxillary/mandible arches (P = 0.82 and 0.26, respectively). The frequency of MIH was more in molars compared to incisors (P < 0.02). CONCLUSIONS: The MIH prevalence in this study was 12.4 percent. According to the MIH severity, degree 2 was the most frequently detected (76.4 percent).

Congenital and acquired defects in enamel of primary teeth: prevalence, severity and risk factors in Brazilian children.

OBJECTIVE: This cross-sectional study evaluated the prevalence of tooth enamel defects and risk factors associated in primary dentition. METHODS: A sample of 656 schoolchildren (population based), aged 4 years old, from Araraquara-SP (Brazil) was evaluated by two trained examiners according to the following indexes: Dental fluorosis (DF), deciduous molar hypomineralization (DMH), non-fluoride related developmental defects of enamel (DDE), tooth erosion and tooth attrition. Structured questionnaires identified socioeconomic condition, medical/dental history, behavior and dietary habits. Data were analyzed using Chi-square tests (p < 0.05). RESULTS: Of the enamel congenital defects, DF was the most prevalent (6.1%, n = 40), followed by DMH (5.6%, n = 37). Of the acquired defects, attrition was the most prevalent (36.9%, n = 242), followed by erosion (2.4%, n = 16). The caries experience was similar between the affected children (29,5%; n = 94) and total sample (30.6%; n = 201). The etiological factors related to congenital defects were: not exclusively fed breast milk (p = 0.003) and jaundice at birth (p < 0.001); the association with acquired defects was found with vomiting frequent episodes (p = 0.037). CONCLUSION: The general prevalence of enamel defects in primary dentition in Araraquara was 48.6%. Enamel defects may be associated with health-related factors and current lifestyle.

The effect of pulp inflammation and premature extraction of primary molars on the successor permanent teeth. A retrospective study.

BACKGROUND: Untreated caries on primary molars often leads to pulp inflammation and extraction. AIM: To retrospectively investigate the effect of pulp inflammation and extraction of primary molars on their successors regarding alignment in the dental arch and developmental enamel defects (DED). DESIGN: The participants in this study were children at public schools in Petropolis (Brazil), who participated in a 3-year longitudinal clinical trial. Children (N = 44) were selected for the present study if they had at least one erupted premolar of which the predecessor primary molar presented pulp inflammation at baseline or during any of the 6-month follow-up assessments. All premolars were examined for DED and misalignment. Distinction was made between extraction performed before (E <8) or after the age of 8 years (E ≥8). Distinction was also made between pulp inflammation occurred before (P < 7) or after the age of 7 years (P ≥ 7). A logistic regression analysis was performed, and the odds ratio was calculated. RESULTS AND CONCLUSIONS: Misalignment occurred more frequently in E <8 as compared to E ≥8 (OR = 2.85; P = .03). There was no significant difference in DED between P < 7 and P ≥ 7. CONCLUSION: Misalignment of premolars occurs more frequently when the predecessor primary molars are extracted before the age of 8 years.

Fatores ambientais e variações genéticas nos genes AMBN, ENAM, KLK4, IRF6, TFGα em pacientes com hipomineralização molar incisivo / Environmental factors and genetic variations in the AMBN, ENAM, KLK4, IRF6, TFGα in patients with incisor molar hypomineralization

Trata-se de uma tese composta por quatro estudos, com o objetivo de avaliar possíveis fatores etiológicos (ambientais e genéticos) associados a presença de Hipomineralização Molar Incisivo (HMI) através de (a) : um estudo observacional transversal para verificar a prevalência de HMI na amostra estudada, junto com uma revisão bibliográfica da prevalência desta condição na população brasileira (objetivo-I); associação de fatores ambientais (durante o período gestacional e nos primeiros anos de vida) relacionados à presença de HMI e a influência destes fatores com a gravidade dessa condição (objetivo-II); associação dos polimorfismos de único nucletídeo (SNPs) localizados nos genes ameloblastina (AMBN), enamelina (ENAM) e calecreína com HMI, além da possível susceptibilidade dos SNPS com à cárie dentária (objetivo-III) e a interação entre fatores ambientais e as variações genéticas nos SNPs localizados nos genes fator 6 regulator de interferon (IRF6) e fator de crescimento transformador alfa (TGFα) estudados em amostras no Rio de Janeiro, Curitiba e turca (Istambul) (objetivo-IV). As coletas de dados do presente estudo foram realizadas em duas etapas: clínica e laboratorial. Os resultados encontrados foram: (I) uma alta heterogeneidade entre os estudos (Q = 52,81, p < 0.01, I2 = 98) com a prevalência final de HMI de 13.48% na população barasileira; (II) as intercorrências na gestação e o uso de medicamentos na primeira infância tiveram uma associação significativa com a presença de HMI (OR = 3,01; 95% CI = 1,74- 8,42; p= 0,014; OR = 3,55; 95% CI = 1,35-10,57; p = 0,019 ), entretanto esses fatores não influenciaram a gravidade dessa condição (p>0,05); (III) houve um resultado significativo no SNP rs2235091 localizado no gene KLK4 com a HMI (p<0,001), e os polimorfismos rs4694075 (AMBN) e rs3796704 (ENAM) mostraram associação com a cárie dentária (p<0.05); (IV) a amostra do Rio de Janeiro apresentou uma interação entre os SNPs rs1523305 (TGFα) e rs642961 (IRF6) (p = 0,03) e entre rs2073487 (IRF6) e rs2902345 (TGFα) (p = 0,04). Além disso, no estudo de Istambul houve uma associação entre o SNP rs930655 (TGFα) com todos os marcadores do gene IRF6 (p<0,05). Em relação ao uso de medicamentos nos primeiros anos de vida houve uma associação com os genes TGFα e IRF6 nas amostras de Curitiba e do Rio de Janeiro (p<0,05). Conclui-se que; (I) a prevalência de HMI é de 13.48% na população brasileira; (II) existe uma relação entre a presença de HMI com complicações que ocorrem durante a gestação (uso de medicamentos) e nos primeiros anos de vida da criança, entretanto esse fatores não influenciaram na gravidade dessa condição; (III) os genes que atuam na formação do esmalte são capazes de influenciar tanto no desenvolvimento da HMI como podem estar associados à cárie dentária e (IV) os polimorfismos localizados nos genes IRF6 e TGFα estão relacionados com o desenvolvimento da HMI. Além disso, o uso de medicamentos nos primeiros anos de vida podem potencializar o desenvolvimento da HMI. (AU)

It is a thesis composed of four studies, with the main to evaluate possible etiological factors (environmental and genetic variation) associated with the presence of MIH in the Brazilian population through (e); (objective-I); a cross-sectional observational study, with a bibliographic review of the prevalence of MIH in Brazil (objective-I); to determine of environmental factors (during in the pregany period and childhood) associated with the presence of MIH, and to evaluate the influence of these factors with the MIH severity (objective-II); associations of single nucleotide polymorphism (SNPs) presentin the genes ameloblastin (AMBN), enamelin (ENAM) and kalekrein (KLK-4) with MIH, in addition to the possible susceptibility of this genes to dental caries (objective-III); and interaction of environmetal factors and to determine the influence of genes interferon regulatory factor 6 (IRF6) and transforming growth factor alpha (TGFα) with MIH in a Brazilian (Rio de Janeiro e Curitiba) and Turkish (Istanbul) population (objective-IV). Data collections of the present study were carried out in two stages: clinical and laboratory.The results found were: (I) a high heterogeneity among the studies (Q = 52.81, p<0.01, I2 = 98) with a final prevalence of 13.48% na Brazilian population; (II) an association between intercurrences during pregnancy and child taking medications with the presence of MIH (OR = 3.55; 95% C.I = 1.35-10.57, p= 0.014; OR = 3.01; 95% C.I = 1.74- 8.42, p= 0.019, respectively), however these factors did not influence the severity of MIH (p>0.05); (III) there was an association between the variant alleles of polymorphisms rs2235091 in the KLK4 gene (p≤0.01) with the presence of MIH and the SNPs rs4694075 in AMBN and rs3796704 in ENAM presents association with dental caries (p<0.05); (IV) that the study from Rio de Janeiro showed a statistical evidence of interaction between TGFA rs1523305 and IRF6 rs642961 (p=0.03) and between genes IRF6 rs2073487 and TGFA rs2902345 (p=0.04). Significant results were found for the study from Istanbul between TGFα rs930655 and all IRF6 markers (p<0.05). Also, there was found statistical evidence for interaction of the SNPs in IRF6 and TGFα genes and medication taking from Curitiba and Rio de Janeiro studies (p<0.05). In summary; (I) the prevalence of MIH is 13.48% in the Brazilian population; (II) there is a relationship between complication that occur during pregnancy and in the child's first years of life with the presence of MIH, however these factors do not influence the severity of this condition; (III) the genes that acting in the enamel formation may influence the development of MIH and them, may be associated with dental caries; (IV) the polymorphisms located in the IRF6 and TGFα genes play a role in the development of MIH in different populations and that these genes may interacting with the medication taken in the first years of life, pontecialising the presence of MIH. (AU)

Risk of Dental Caries in Primary Teeth with Developmental Defects of Enamel: A Longitudinal Study with a Multilevel Approach.

The risk of dental caries seems to be greater in the presence of developmental defects of enamel (DDE). The aim was to determine whether the presence of DDE in the primary teeth of preschool children increases the risk of dental caries in the primary dentition after a period of approximately 2 years. This study was conducted in two stages: baseline (T0) and follow-up (T1). At T0, examinations were conducted for the diagnosis of enamel defects using the DDE index (FDI, 1992), dental caries, and oral hygiene. The participants were allocated to two groups according to the presence (affected) or absence (unaffected) of DDE. At the second evaluation (T1), examinations were performed for the diagnosis of dental caries. Poisson regression analysis with a multilevel approach was used to determine the association between DDE and dental caries. The two levels of the analysis were tooth and child. Among the 339 children (113 affected and 226 unaffected) examined at baseline (T0), 325 were re-examined at follow-up (T1). According to the multilevel analysis, teeth with enamel hypoplasia had a greater risk of having dental caries (RR: 1.99; 95% CI: 1.19-3.33). The risk of caries was greater on posterior teeth (RR: 2.59; 95% CI: 2.18-3.07) and maxillary teeth (RR: 1.48; 95% CI: 1.26-1.75) that had DDE at T0. On the child level, dental caries at T1 was associated with having dental caries at T0 (RR: 1.38; 95% CI: 1.32-1.46). In conclusion, enamel hypoplasia and previous dental caries are risk factors for carious lesions in the primary dentition.

Impact of Developmental enamel defects on quality of life in 5-year-old children.

BACKGROUND: Developmental enamel defects (DDE) represent one of the prevalent oral problems in childhood; however, few studies have evaluated its impact on quality of life in the children's own perception. AIM: To evaluate the DDE impact on quality of life of 5-year-old children. METHODS: This cross-sectional observational study assessed 566 children aged 5 years old, in Teresina, Piauí, Brazil, according to their self-perceptions. Children answered the Pediatric Quality of Life Inventory™ Version 4.0 and Oral Health Scale. The dmft index, modified DDE index and Foster and Hamilton criteria were used to diagnose dental caries, DDE and malocclusion, respectively. A single examiner performed the clinical examination. Descriptive analyses and Poisson regression with robust variance were performed. RESULTS: The prevalence of DDE was 33.7%. For children's self-reports, the presence of DDE had a negative association with oral health-related quality of life (OHRQoL; PR 1.09, 95% CI 1.02-1.15). Enamel hypoplasia had a negative impact on the physical function (PR 1.05; 95% CI 1.01-1.10) and oral health (PR 1.06, 95% CI 1.01-1.11) domains. Diffuse opacity had a negative impact on the social aspect (PR 1.09, 95% CI 1.02-1.18). CONCLUSIONS: Enamel defects had a negative impact on OHRQoL according to the self-reports of the children.

Crypt fenestration enamel defects and early life stress: Contextual explorations of growth and mortality in Colonial Peru.

OBJECTIVES: This study provides a comprehensive analysis of crypt fenestration enamel defects (CFEDs) from the Eten and Mórrope communities, Colonial period (A.D. 1,530-1,750), Lambayeque Valley, Peru. The goal is to help clarify the role of these lesions as reflections of early life environments as well as relationships growth and survival at future ages. MATERIALS AND METHODS: CFED absence/presence was recorded in the mandibular canines of 105 individuals and 202 teeth. Defect prevalence was compared between the Eten and Mórrope sites using a proportions test. Femoral growth residuals were compared between CFED present and absent samples. Mortality risk was evaluated using Kaplan-Meier survival analysis. RESULTS: CFED frequencies at Eten and Mórrope were similar to previous studies. Greater frequencies of CFEDs were found at Eten compared to Mórrope. There was no association between skeletal growth and CFEDs. No differences in mortality were found between CFED present and absent individuals within each site. General survivorship at Eten was significantly greater than Mórrope. However, individuals without CFEDs at Eten had greater survivorship than those with and without CFEDs at Mórrope. Individuals with CFEDs at Eten had greater survivorship than those with CFEDs at Mórrope. These differences begin around 1.7 years. CONCLUSIONS: CFEDs may be associated with stress experience, but associations with growth and survivorship at later ages is context dependent. CFED prevalence is an ambiguous indicator of stress when used in the absence of mortality data, and even under those circumstances, appears limited by differences in local demography.

Análisis de la relación entre la hipomineralización incisivo molar y los factores asociados a su etiología / Analysis of the relationship between molar incisor hypomineralization and the factors associated with its etiology

RESUMEN El objetivo de este artículo es analizar la relación entre la hipomineralización incisivo molar (HIM) y los factores asociados a su etiología publicados en la literatura. Material y métodos: El estudio se basó en una búsqueda de estudios epidemiológicos de casos y controles de HIM que describieron un factor etiológico asociado para obtener las odds ratio (OR) necesarias para analizar la prevalencia del factor afectado y su posible papel en la etiología de la condición. Resultados: Ocho artículos cumplieron los criterios para el análisis. La población total analizada consistió en una muestra de 7,901 sujetos, de los cuales 992 tenían HIM. En estos sujetos fueron reportados como factor asociado (FA) para HIM: asma (OR = 4.4954), uso de antibióticos (OR = 5.5348), fiebre (OR = 4.0545) y neumonía. Conclusión: Los resultados del presente estudio sugieren que un FA común a todos los casos de HIM estudiados es un proceso inflamatorio que conduce a una mayor concentración de agentes en el microambiente en el que se desarrollan las células formadoras del esmalte, lo que aumenta la presencia de proteínas en la matriz del esmalte o interfieren con su hidrólisis y eliminación y produce como resultado una deficiente mineralización.

ABSTRACT Hypomineralization enamel of the first permanent molars is the most common developmental abnormalities observed in the teeth. The aetiology of MIH remains unclear and may have a multifactor aetiology. The aim of this paper is to analyze the relationship between MIH and associated factors published in the literature. Material and methods: The study was based on a search for epidemiological case-control studies of MIH that described an associated etiological factor, in order to obtain the odds ratios needed to analyze the prevalence of the factor concerned and its possible role in the etiology of the condition. Results: The initial search produced 50 articles, eight of which met the criteria for the analysis. The total population analyzed consisted of a sample of 7,901 subjects, 992 of whom had MIH (i.e., a prevalence of 12.55%). Asthma was reported as an etiological factor in five papers, which included 474 subjects with MIH with an OR of 4.4954 (p < 0.0001). Antibiotic use was reported as an etiological factor in three papers, which reported on a population of 231 subjects with MIH and OR of 5.5348 (p < 0.0001). Fever was reported as an etiological factor in two papers, involving a population of 176 subjects with MIH and an OR of 4.0545 (p < 0.0001). Pneumonia was reported as an etiological factor in two papers, which dealt with a population of 454 cases of MIH and produced an OR of 2.285 (p < 0.0001). Conclusion: The results of the present study suggest that one etiological factor common to all of the MIH cases studied is an infl ammatory process, in which the presence of agents that cause alterations in ameloblasts can lead to higher concentrations of these agents in the microenvironment in which enamel forming cells develop, thus increasing the presence of proteins in the enamel matrix or interfering with their hydrolysis and removal, producing defects in enamel mineralization.

Direct evidence that KLK4 is a hydroxyapatite-binding protein.

The protease kallikrein 4 (KLK4) plays a pivotal role during dental enamel formation by degrading the major enamel protein, amelogenin, prior to the final steps of enamel hardening. KLK4 dysfunction is known to cause some types of developmental defect in enamel but the mechanisms responsible for transient retention of KLK4 in semi-hardened enamel matrix remain unclear. To address contradictory reports about the affinity of KLK4 for enamel hydroxyapatite-like mineral, we used pure components in quasi-physiological conditions and found that KLK4 binds hydroxyapatite directly. Hypothesising KLK4 self-destructs once amelogenin is degraded, biochemical analyses revealed that KLK4 progressively lost activity, became aggregated, and autofragmented when incubated without substrate in both the presence and absence of reducer. However, with non-ionic detergent present as proxy substrate, KLK4 remained active and intact throughout. These findings prompt a new mechanistic model and line of enquiry into the role of KLK4 in enamel hardening and malformation.

Signos dentales de la sífilis congénita / Dental signs of congenital syphilis

La sífilis congénita es causada por una bacteria en forma de espiroqueta denominada Treponema pallidum; se transmite de la madre infectadaaal feto. Esta enfermedad causa distintas alteraciones sistémicas, dependiendoen qué fase de la sífilis se infecta el producto. El incremento de casos a nivel mundial hace necesario el estudio de su epidemiología y que se implementen programas de salud que atiendan a la población embarazada, con seguimiento por medio del control prenatal. Se estima que 1.5 por ciento de las mujeres embarazadas a nivel mundial la padecen. Las alteraciones dentales tienen su etiología en la infl amación provocada por la espiroqueta al momento de la amelogénesis; los signos dentales característicos de la sífi lis congénita son los incisivos de Hutchinson, molares de mora y, en menor medida, los caninos de Fournier. El propósito de este trabajo es hacer una revisión de la literatura, enfatizando en las características clínicas de la enfermedad que nos permitan realizar el diagnóstico de la sífilis congénita.

Congenital syphilis is caused by a spirochete bacterium called Treponema pallidum; it is transmitted from the infected mother to the fetus. This disease causes diff erent systemic alterations, dependingon which phase of syphilis the product is infected. The increase incases worldwide makes it necessary to study its epidemiology andto implement health programs that serve the pregnant population, with follow-up through prenatal control. It is estimated that 1.5% of pregnant women world wide suff er from it. Dental alterations have theiretiology in the infl ammation caused by the spirochete at the momentof amelogenesis; the characteristic dental signs of congenital syphilisare Hutchinson incisors, blackberry molars, and, to a lesser extent, Fournier’s canines. The purpose of this paper is to review the literature, emphasizing the clinical characteristics of the disease that may allowus to diagnose congenital syphilis.

Malnutrition-related early childhood exposures and enamel defects in the permanent dentition: A longitudinal study from the Bolivian Amazon.

OBJECTIVES: We investigated the relationship between early childhood malnutrition-related measures and subsequent enamel defects in the permanent dentition. MATERIALS AND METHODS: This cohort study included 349 Amerindian adolescents (10-17 years, 52% male) from the Bolivian Amazon. Exposures included: stunted growth (height-for-age z-scores), underweight (weight-for-age z-scores), anemia (hemoglobin), acute inflammation (C-reactive protein) and parasitic infection (hookworm). We measured the occurrence (no/yes) and extent (<1/3, 1/3-2/3, >2/3) of enamel defects. We estimated associations between childhood exposures and enamel defect measures using log-binomial and multinomial logistic regression. RESULTS: The prevalence of an enamel defect characterized by an orange peel texture on a large central depression on the labial surface of the central maxillary incisors was 92.3%. During childhood (1-4 years), participants had a high prevalence of stunted growth (75.2%), anemia (56.9%), acute inflammation (39.1%), and hookworm infection (49.6%). We observed associations between childhood height-for-age (OR = 0.65; P = 0.028 for >2/3 extent vs. no EH) and gastrointestinal hookworm infection (OR = 3.43; P = 0.035 for >2/3 extent vs. no defects or <1/3 extent) with enamel defects. DISCUSSION: The study describes a possibly novel form of enamel hypoplasia and provides evidence for associations of malnutrition-related measures in early childhood, including stunted growth and parasitic helminth infection, with the observed enamel defects.

Dental enamel as biomarker for environmental contaminants in relevant industrialized estuary areas in São Paulo, Brazil.

Heavy metal contamination is a long-standing and very well-known public health problem, and its exposure can cause damage to several organs of human body, especially on the central nervous system of young children and teenagers. The aim of this article is to evaluate lead, cadmium, and manganese contamination in 125 children from 6 to 13 years old living in contaminated areas during the period from 2006 to 2009 (São Vicente, Cubatão Downtown, Bertioga and Cubatão Pilões/Água Fria). This estuary area is the most important example of environmental degradation by chemicals from industrial sources. This is a cross-sectional study through clinical examinations and dental enamel tests. All mothers from these children lived in the area since before the pregnancy. Lead, cadmium, and manganese levels (µg/g) were measured on dental enamel samples through graphite furnace atomic absorption spectrometry, searching for the occurrence of heavy metals. The mean lead concentrations were 139.48 µg/g in Cubatão Pilões/Água Fria, 170.45 µg/g in Cubatão Downtown, 213.52 µg/g in São Vicente, and 151.89 µg/g in Bertioga. The mean cadmium concentrations were 10.83 µg/g in Cubatão Pilões/Água Fria, 12.58 µg/g in Cubatão Downtown, 10.92 µg/g in São Vicente, and 14.57 µg/g in Bertioga. The mean manganese concentrations were 23.49 µg/g in Cubatão Pilões/Água Fria, 30.90 µg/g in Cubatão Downtown, 41.46 µg/g in São Vicente, and 42.00 µg/g in Bertioga. Dental surface enamel may be used as an efficient biomarker of past environmental exposure to lead, manganese, and cadmium which are associated to well-known sources of heavy metal contamination. The results suggest that the evaluated children were exposed to sources of lead, cadmium, and manganese since before their conceptions. Although Bertioga initially was chosen as a control area of this study, it was also was verified to have heavy metal contamination on examined children.