Developmental Defects Of Enamel Research Articles

Dental caries and developmental defects of enamel in cerebral palsy: A meta-analysis.

This systematic review and meta-analysis aimed to compare the occurrence of dental caries and developmental defects of enamel (DDE) in individuals with and without cerebral palsy (CP). We conducted searches across five databases and the grey literature. Data were organized using EndNote 20. Reporting followed the MOOSE checklist. A random-effects model meta-analyses were conducted using RStudio, presenting results as mean difference (MD), odds ratio (OR), and 95% confidence interval (CI). The risk of bias of studies was analyzed using the Newcastle-Ottawa Scale, and the certainty of evidence was assessed using GRADE. Among 1336 identified records, 25 studies involving 59,997 participants (mean age: 11.1 years) were included. Data of 12 were pooled into meta-analyses. No significant differences were found between CP and non-CP individuals across indices: DMFT (k = 7) (MD = 0.31; 95% CI [-0.42-1.05]), dmft (k = 4) (MD = 0.31; 95% CI [-0.50-1.14]), DMFS (k = 2) (MD = -0.61; 95% CI [-20.56-19.33]), dmfs (k = 3) (MD = 0.54; 95% CI [-1.09-2.17]), and DDE (k = 3) (OR = 0.80, 95% CI [0.09-7.31]). The certainty of evidence was very low. Individuals with CP do not appear to differ significantly from those without CP in terms of dental caries experience and DDE.

Bayesian modeling of spatially differentiated multivariate enamel defects of the children’s primary maxillary central incisor teeth

BackgroundThe analysis of dental caries has been a major focus of recent work on modeling dental defect data. While a dental caries focus is of major importance in dental research, the examination of developmental defects which could also contribute at an early stage of dental caries formation, is also of potential interest. This paper proposes a set of methods which address the appearance of different combinations of defects across different tooth regions. In our modeling we assess the linkages between tooth region development and both the type of defect and associations with etiological predictors of the defects which could be influential at different times during the tooth crown development.MethodsWe develop different hierarchical model formulations under the Bayesian paradigm to assess exposures during primary central incisor (PMCI) tooth development and PMCI defects. We evaluate the Bayesian hierarchical models under various simulation scenarios to compare their performance with both simulated dental defect data and real data from a motivating application.ResultsThe proposed model provides inference on identifying a subset of etiological predictors of an individual defect accounting for the correlation between tooth regions and on identifying a subset of etiological predictors for the joint effect of defects. Furthermore, the model provides inference on the correlation between the regions of the teeth as well as between the joint effect of the developmental enamel defects and dental caries. Simulation results show that the proposed model consistently yields steady inferences in identifying etiological biomarkers associated with the outcome of localized developmental enamel defects and dental caries under varying simulation scenarios as deemed by small mean square error (MSE) when comparing the simulation results to real application results.ConclusionWe evaluate the proposed model under varying simulation scenarios to develop a model for multivariate dental defects and dental caries assuming a flexible covariance structure that can handle regional and joint effects. The proposed model shed new light on methods for capturing inclusive predictors in different multivariate joint models under the same covariance structure and provides a natural extension to a nested hierarchical model.

The prevalence of developmental defects of enamel in people with cystic fibrosis: a systematic review

BackgroundOral health impacts systemic health, individual well-being, and quality of life. It is important to identify conditions that may exacerbate oral disease to aid public health and policy development and promote targeted patient treatment strategies. Developmental defects can increase an individual’s risk of dental caries, hypersensitivity, premature tooth wear, erosion, and poor aesthetics. As part of an ongoing study assessing oral health in adults with cystic fibrosis at Cork University Dental School and Hospital, a systematic review of available literature was conducted to assess the prevalence of enamel defects in people with cystic fibrosis.AimsTo critically evaluate the literature to determine if the prevalence of developmental defects of enamel is higher in people with cystic fibrosis (PwCF).MethodsData Sources: Three online databases were searched Embase, Scopus, and Web of Science Core Collection. Studies that examined an association between cystic fibrosis and developmental defects of enamel were included in this systematic review.ResultsThe initial search identified 116 publications from the following databases Embase, Web of Science Core Collection, and Scopus. Eleven studies were included for qualitative analysis. Nine studies concluded that PwCF had a higher prevalence of enamel defects than control people and one study found no difference in cystic fibrosis (CF) status. All studies had a risk of bias that may influence study results and their interpretation.ConclusionsThe results of the systematic review show a consistent pattern that PwCF have a higher prevalence of DDE than people without CF. Genetic dysfunction, chronic systemic infections, and long-term antibiotic use are possible aetiological causes. This review highlights the need for future studies to investigate if DDEs are caused by the underlying CFTR mutation or as a consequence of disease manifestations and/or management.

Is Italian Dentists’ Knowledge of Enamel Development Defects Adequate? A Nationwide Survey

ObjectivesCorrect identification and management of Developmental Defects of Enamel (DDEs) are essential to provide the best possible treatment. The present survey aims to investigate Italian dentists’ knowledge of DDEs, their ability to recognise the different clinical pictures, and to choose the most appropriate clinical approach. MethodsA cross-sectional survey was planned based on a questionnaire including 27 closed-ended questions, and that proposed 4 clinical pictures, molar incisor hypomineralisation (MIH), amelogenesis imperfecta (AI), dental fluorosis (DF), and an initial caries lesion (ICL). It was distributed by e-mail to all Italian dentists (N = 63,883) through the Italian Federation of Doctors and Dentists. Discrete variables were expressed as absolute and relative frequencies (%). A multivariate analysis assessed whether socio-demographic variables correlated with the answers’ truthfulness. ResultsAbout 5017 questionnaires were included and analysed. Although 90.19% of the sample stated that they had received information on DDEs, a significant percentage did not recognise MIH (36.36%), AI (48.34%), DF (71.50%), and ICL (46.62%). Only 57.07% correctly classified enamel hypomineralisation as a qualitative defect, and even fewer, 54.45%, classified enamel hypoplasia as a quantitative defect. According to the logistic regressions, female dentists, dentists who treat mainly children and received information about DDEs, were more likely to recognise the 4 clinical pictures (P < .01). ConclusionsItalian dentists showed many knowledge gaps on DDEs that need to be filled; those who received formal training were more capable of correctly identifying the defects and were more likely to prescribe an appropriate management approach for the defects. Clinical significanceIncreasing university courses and continuing education on diagnosing and managing DDEs seems reasonable to fill the knowledge gap on DDEs.

The association between Dental Fluorosis and COL1A2 gene polymorphism among a Tunisian Population

Dental fluorosis (DF) is a prevalent developmental defect of tooth enamel caused by exposure to excessive fluoride, with the severity dependent on various factors. This study aimed to investigate the association between DF and a specific genetic polymorphism (rs412777) in the COL1A2 gene among a Tunisian population. A case-control study was conducted from July to November 2022, involving a total of 95 participants including 51 cases and 44 controls. Dental examinations and genetic analysis were performed to assess the relationship between the COL1A2 gene polymorphism and DF.The results of allelic distribution revealed that A allele carriers were significantly protected against (DF) when compared to those with the C allele (C vs. A, p = 0.001; OR = 0.375 (0.207–0.672)). This suggests a strong correlation between the presence of the C allele and the risk of developing DF. Additionally, significant association between the CC genotype of rs412777 and an increased risk of DF was found under both codominant and dominant genetic models (P = 0.002 and P < 0.001 respectively).The findings suggest that genetic predisposition plays a relevant role in the development of DF. Further research is needed to explore the potential use of genetic markers for DF and their implications for public health. This study provides the first insights into the genetic factors associated with DF in the Tunisian population, contributing to our understanding of this prevalent dental condition.

Prenatal exposure to environmental toxins and comprehensive dental findings in a population cohort of children.

Environmental toxins are known to have many impacts on growth and development in humans, starting in utero. Alterations in amelogenesis, caused by chemical and physical trauma that occur during the antenatal, perinatal and postnatal time periods, may result in developmental defects in deciduous and permanent tooth enamel, as demonstrated in animal studies. These defects can be clinically visible and result in a variety of morphological and functional problems in the dentition. Since enamel does not remodel after formation, it may serve as a permanent record of insults during organ development.Our primary purpose was to investigate any possible relationship between intrauterine exposure to endocrine disrupting chemicals (phenols and phthalates) and developmental defects in enamel in children, while also accounting for fluoride exposure. Our secondary purpose was to report descriptively on findings from comprehensive dental examinations performed on 356 children that were drawn from the general paediatric population. A cohort of children from the Utah Children's Project (N = 356) that had full medical exams, comprehensive medical and family histories and available biospecimens were given extraoral and intraoral examinations. They also completed an oral health questionnaire. Standardized intraoral photographs were taken of the teeth and viewed by standardised examiners and the dental observations were recorded for a full inventory of findings, including: tooth morphology, caries, restorations, colorations, attrition, erosion, fractures and hypomineralization. Perinatal maternal urine samples were assessed for the concentration of fluoride, phenols and phthalates, including bisphenol A (BPA).Pairwise statistical analyses were done to correlate the dental findings with one another and with the presence of environment chemicals found in the urine samples. Hypomineralization was the most common finding (96% of children; 37% of deciduous teeth, 42% of permanent teeth), consistent with molar incisor hypomineralization (MIH) described in other human populations. No consistent correlations were seen between dental findings and the presence of phenols and phthalates in prenatal urine, but the number of samples available for the assessment was limited (n = 35).In conclusion, we found a high proportion of dental hypomineralization in a population based paediatric cohort, but did not find an association with prenatal exposure to phenols and phthalates.

Linear enamel hypoplasia in Homo naledi reappraised in light of new Retzius periodicities.

Among low-latitude apes, developmental defects of enamel often recur twice yearly, linkable to environmental cycles. Surprisingly, teeth of Homo naledi from Rising Star in South Africa (241-335 kya), a higher latitude site with today a single rainy season, also exhibit bimodally distributed hypoplastic enamel defects, but with uncertain timing and etiology. Newly determined Retzius periodicities for enamel formation in this taxon enable a reconstruction of the temporal patterning of childhood stress. Using high resolution casts of 31 isolated anterior teeth from H. naledi, 82 enamel defects (linear enamel hypoplasia [LEH]) were identified. Seventeen teeth are assigned to three individuals. Perikymata in the occlusal wall of enamel furrows and between the onsets of successive LEH were visualized with scanning electron microscopy and counted. Defects were measured with an optical scanner. Conversion of perikymata counts to estimates of LEH duration and inter-LEH interval draws upon Retzius periodicities of 9 and 11 days. Anterior teeth record more than a year of developmental distress, expressed as two asymmetric intervals centered on 4.5 and 7.5 months bounded by three LEH. Durations, also, show bimodal distributions, lasting 3 or 12 weeks. Short duration LEH are more severe than long duration. Relative incisor/canine rates of formation are indistinguishable from modern humans. We invoke a disease and dearth model, with short episodes of distress reflecting onset of disease in young infants, lasting about 3 weeks, followed by a season of undernutrition, possibly intensified by secondary plant compounds, spanning about 12 weeks, inferably coincident with austral winter.

Possible Etiological Factors for the Development of Molar Incisor Hypomineralization (MIH) in Austrian Children.

Molar incisor hypomineralization (MIH) is a developmental enamel defect that primarily affects the first permanent molars and sometimes the incisors. Its increasing prevalence worldwide has raised clinical concerns, yet its exact cause remains unknown. This study aimed to assess potential factors influencing MIH development by analyzing the medical history of children aged 6 to 12 years using a questionnaire. This study included 100 children aged 6-12 years diagnosed with MIH during dental examination, and 100 age-matched children in the non-MIH (healthy) group from the Department of Pediatric Dentistry, University Clinic of Dentistry, Medical University of Vienna. The parents of the participants completed a two-page questionnaire regarding possible etiological factors of MIH. The data analysis involved 100 children with MIH (mean age 8.5; ±1.3; 52% female) and 100 children in the healthy group (mean age 9.2; ±1.3; 42% female). The optimized binary logistic regression analysis revealed a significant association between MIH development and cesarean-section delivery (OR = 3; CI = [1.5-6.2]) and sixth disease (roseola) (OR = 3.5; CI = [1.5-8.0]). This study suggests that cesarean-section delivery and sixth disease (roseola) might increase the likelihood of MIH development in children.

The prevalence of developmental defects of enamel in a cohort of adults with cystic fibrosis – A cross sectional study

ObjectivesCystic Fibrosis is an autosomal recessive condition. It is a multisystem disease treated with a broad range of pharmacological therapies, diet and nutrition, and physiotherapy. Previous studies suggest that people with cystic fibrosis have a higher prevalence of developmental defects of enamel which may place this population at a greater risk of developing oral diseases such as caries. The aim of this study was to assess a cohort of people with cystic fibrosis (PwCF) for the presence of developmental defects of enamel and compare the results with a control group of people without cystic fibrosis. MethodsA cross sectional study involving 92 participants with cystic fibrosis and 92 controls was conducted in Cork University Dental School & Hospital. All participants completed a detailed questionnaire prior to undergoing a full clinical examination. The Developmental Defect of Enamel Index was used as a measurement index. All data was statistically analysed with the help of statisticians from Cystic Fibrosis Registry of Ireland. Results64 % (n = 59) of PwCF had enamel defects compared to just 30 % (n = 28) of people without cystic fibrosis. The median number of teeth affected by enamel defects in the study group was 1.5, compared to 0 in the control group. ConclusionIn this study the cohort of PwCF had more enamel defects than people without CF. Further research is required to investigate the aetiology of these findings. Clinical significanceClinicians should be vigilant after teeth have erupted in PwCF as they may have an increased susceptibility to developmental defects of enamel.

Melatonin ameliorates inflammation-induced developmental defects of enamel by upregulating regulator of G protein signaling 2

Background/purposeDevelopmental defects of enamel (DDE) is a dental disease with a high prevalence and no effective means of prevention. One of the major causes of DDE is infection, but the pathogenesis is still unclear. Melatonin is known for its anti-inflammatory and mineralization-promoting activities. However, the effects of melatonin on inflammation-induced DDE remain unknown. Here, we investigated the pathogenesis and potential therapeutic targets of inflammation-induced DDE. Materials and methodsFirst, the effect of lipopolysaccharide-induced inflammation in pregnant mice on the enamel mineralization of the offspring was detected by 3D X-ray microscope analysis, immunohistochemical assays, and quantitative real-time polymerase chain reaction (qRT-PCR). Then, the ameloblastic differentiation ability of ameloblast lineage cells (ALCs) in macrophage conditioned medium (CM) was detected. Subsequently, ameloblastic mineralization after melatonin administration was studied both in vivo and in vitro. The underlying mechanism of melatonin was investigated by RNA sequencing and small interfering RNA transfection. ResultsEnamel mineralization was decreased in the inflammatory environment both in vivo and in vitro. Furthermore, melatonin treatment ameliorated these defects. RNA sequencing analysis revealed that regulator of G protein signaling 2 (Rgs2) was downregulated in the inflammation group, whereas it was upregulated after the addition of melatonin. Further studies showed that Rgs2 knockdown resulted in decreased ameloblastic mineralization in ALCs. After Rgs2 knockdown of ALCs in M1-CM with melatonin, the effect of melatonin-mediated attenuation of DDE was greatly reduced. ConclusionOur results demonstrate that melatonin ameliorates inflammation-induced DDE by upregulating RGS2, suggesting that RGS2 is a potential therapeutic target for inflammation-induced DDE.

The Impact of Molar Incisor Hypomineralisation on Children and Adolescents: A Narrative Review

Molar incisor hypomineralisation (MIH) is a qualitative developmental enamel defect with a prevalence of 13% worldwide. This review aims to outline the current evidence regarding the impact of MIH on children’s oral health and, more broadly, their day-to-day activities. MIH is associated with negative sequelae, including hypersensitivity, post-eruptive breakdown, the rapid development of carious lesions and poor aesthetics. Other concerns pertain to the clinical management of MIH and include difficulty in achieving local anaesthesia, increased dental fear and anxiety (DFA) and increased behaviour management problems. Oral health-related quality of life (OHRQoL) is the most standardised measure of patient impact; however, no instruments have been validated for use in MIH populations. The few existing observational studies investigating the impact of MIH on OHRQoL in children have produced conflicting results. Interventions to alleviate hypersensitivity and improve aesthetics had a positive impact on the OHRQoL of MIH-affected children. Multiple methodological issues make it difficult to measure the impact of MIH, including heterogeneity in the MIH severity classification, an overlap in the indices used to diagnose dental caries and MIH as well as the subjectivity of outcome measures for hypersensitivity and DFA.

Treatment Strategies for Incisors of Children Affected by Molar Incisor Hypomineralization: A Narrative Review

Today, molar incisor hypomineralization (MIH), which affects approximately one in seven children, is defined as a hypomineralized developmental enamel defect that often impacts at least one permanent first molar and frequently affects permanent incisors as well. Symptoms and signs include demarcated opacities of various colors, post-eruptive enamel deterioration, atypical caries and restorations, hypersensitivity, tooth loss due to MIH, and difficulty in achieving anesthesia. A detailed review of the scientific literature shows that there are many studies evaluating different treatment approaches for permanent first molars affected by MIH. On the other hand, there are very few scientific studies evaluating treatment approaches for affected incisors in patients with MIH. Most of these studies consist of case reports or series. White/creamy and/or yellow/brown demarcated opacities are commonly observed in affected incisors in patients with MIH. While these opacities increase the susceptibility of enamel to deterioration and dental caries, they also cause aesthetic problems and related psychosocial consequences. Treatment methods, such as resin infiltration, microabrasion, and/or dental bleaching, have been proposed for aesthetic and restorative purposes in affected incisors in patients with MIH. Additionally, various approaches to increase mineral content and relieve hypersensitivity have been recommended. The number of randomized controlled and prospective studies is quite low, but many case reports and case series have been encountered. The purpose of this review was to provide a comprehensive overview of the different treatment management modalities for permanent incisors affected by MIH. As a result, while resin infiltration, dental bleaching, microabrasion, and/or etch–bleach–seal techniques are preferred for aesthetic and restorative purposes in these teeth, it has been observed that agents containing casein phosphopeptide amorphous calcium phosphate, casein phosphopeptide amorphous calcium fluoride phosphate, fluoride, and calcium glycerophosphate increase the mineral content. Additionally, studies have reported that ozone and low-level laser therapy, in addition to these remineralizing agents, reduce hypersensitivity in these teeth. Although the findings of this review indicate that the level of evidence for current approaches is not high, clinicians may prefer one or more of the treatment approaches mentioned in this article based on experience and patient expectations.

Natal factors affecting developmental defects of enamel in preterm infants: a prospective cohort study

This study investigated natal factors influencing developmental defects of enamel (DDE) in premature infants using a newly refined preterm developmental defects of enamel (PDDE) index. Dental examinations were conducted on a cohort of 118 preterm infants (average age 3.5 ± 1.4 years) to record PDDE scores, while reviewing their medical records to examine natal factors. According to the logistic regression analysis, factors related to DDE prevalence were advanced maternal age, gestational age < 28 weeks, birth weight < 1000 g, 1 min APGAR score < 7, and hospitalization period > 2 months, which were significantly higher by 2.91, 5.53, 7.63, 10.02, and 4.0 times, respectively. According to regression analysis with generalized linear models, the PDDE scores were approximately 7.65, 4.96, and 15.0 points higher in premature children diagnosed with bronchopulmonary dysplasia, intraventricular hemorrhage, and necrotizing enterocolitis, respectively. When endotracheal intubation was performed, the PDDE score was 5.06 points higher. The prevalence of PDDE was primarily observed bilaterally in the maxillary anterior teeth. Extremely preterm infants showed significantly delayed tooth eruption, suggesting that the influence of gestational age on dental development rates. Identifying the factors related to DDE in premature children can inform early dental interventions to support the oral health of high-risk children.

Are low serum levels of Vitamin D associated with dental developmental defects in primary teeth? A systematic review.

To identify, qualify and synthesize all studies that assessed if low serum level of 25(OH)D (<50 nmol/L) is associated with dental developmental defects (DDD) in primary teeth. Observational studies or clinical trials were included if measured 25(OH)D serum levels in pregnant women and/or in their children (up to 3 years old) and evaluated the occurrence of DDD in the primary dentition of offspring associated with the low 25(OH)D levels. Literature reviews, case reports, laboratory and/or animals' studies, conference abstracts, letters to the editor, book chapters and clinical protocols were excluded. Searches were carried out in 6 electronic databases and in the gray literature until March 2023, without restrictions. The study quality was assessed by the Newcastle-Ottawa Scale and the certainty of the evidence by GRADE. Data were descriptively synthesized considering the association between DDD and 25(OH)D levels. Seven studies were included. Only developmental enamel defects (DED) were observed after examination of 6651 children. The incidence of DED ranged from 8.9% to 66%. Six studies found no association between low levels of 25(OH)D and DED. However, one reported correlation between hypomineralization of the primary second molar (HSMD) and low levels of 25(OH)D at birth. Methodological flaws were observed in all studies and the certainty of the evidence was very low. Although HSMD was the only DDD associated with low levels of 25(OH)D in children, the available evidence is still not conclusive. More robust studies are needed to endorse the biological plausibility of DDD in primary teeth due to low serum levels of 25(OH)D in pregnant women or in their children. FAPERJ financed this study, which was registered in PROSPERO (CRD42022357511).

Prenatal, neonatal and postnatal factors and the developmental defects of dental enamel.

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. 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. 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. 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.

Oral conditions of children with microcephaly associated with congenital Zika syndrome: a cross-sectional study.

The aim of the present study was to compare the oral conditions of children with congenital Zika syndrome (CZS)-associated microcephaly, non-CZS-associated microcephaly, and normotypical children, as well as to characterize their sociodemographic aspects and medical history. A paired cross-sectional study was carried out on 14 children with CZS-associated microcephaly and 24 age-matched controls, in Belo Horizonte, in southeastern Brazil. Children's oral conditions were assessed: dental caries experience (dmft/DMFT indices); developmental defects of enamel (DDE) index; dental anomalies; mucosal changes; lip sealing, and malocclusion (overjet, overbite, and/or posterior crossbite alterations). The quality of oral hygiene was analyzed by the simplified oral hygiene index. The children's mothers also answered a questionnaire about sociodemographic and medical history data. The variables were analyzed descriptively. Female participants were more prevalent (60.5%), and the mean age of the participants was 4.9 years (±1.4) (range: 2-8 years) and 92.1% of their exhibited some oral condition. All participants with CZS-associated microcephaly showed absence of lip sealing and had malocclusion (100.0%). When compared to the other groups, children with CZS had a higher percentage of dental anomalies (35.7%), mucosal changes (71.4%), and unsatisfactory oral hygiene (64.3%). In a sample composed mainly of female participants aged less than 5 years, the prevalence of oral conditions and unsatisfactory oral hygiene was higher in the group with CZS-associated microcephaly, followed by the group with non-CZS-associated microcephaly. Normotypical children had the highest percentage of dental caries experience.

Different approaches for aesthetic management of molar-incisor hypo-mineralization: two case reports

Background: Molar-incisor hypo-mineralization (MIH) is a developmental enamel defect that affect one or more permanent first molars, with or without incisor teeth involvement. When incisors are affected, that might lead to aesthetic concerns and consequently, negative impact on the child&amp;apos;s quality of life. Hence, this study presented and discussed the conservative treatment modalities for maxillary incisors with discolored enamel defects. Case Presentation: Two 12-year-old female patients was referred from pediatric clinics to treat anterior teeth discolorations after management of affected first molars. In the first case, the defect was more heterogenous with yellow-brownish discoloration. To remove yellow-brownish discoloration, in-office bleaching with 37% hydrogen peroxide was performed, followed by home bleaching with 10% carbamide peroxide for one week. Then, resin infiltration (RI) was performed to seal the porous enamel and to mask the white enamel defects. In the second case, the white opacities were more homogenous, therefore, only RI treatment was applied. Conclusion: Aesthetic management of MIH patients should follow more conservative approaches like dental bleach systems and resin infiltration.

A minimal interventive protocol using antimicrobial photodynamic therapy on teeth with molar incisor hypomineralization: A case report.

Molar incisor hypomineralization (MIH) is a qualitative developmental defect of enamel that occurs during the mineralization phase. Patients with MIH have increased risk of caries, hypersensitivity, and restoration failures. The present case report describes the treatment of a 10-year-old patient exhibiting two teeth with atypical carious lesions. A minimal interventive protocol was instituted combining antimicrobial photodynamic therapy and the selective chemical-mechanical removal of the carious tissue using the product Papacárie Duo®. This protocol is promising for the decontamination and control of hypersensitivity in teeth with MIH.

Could sleep quality in pregnant women be related to developmental defects of enamel in children?

Anatomical, physiological and hormonal changes occur in women during pregnancy. These phenomena can affect sleep quality, exerting a negative impact on health. Studies suggest that sleep disorders in this period can also affect the health of the fetus. Sleep disorders may interfere with the expression of genes associated with amelogenesis in the fetus. Clock genes are the basis of internal time keeping (circadian rhythm) and are involved in the formation of mineralized dental tissues. Fetal tooth formation is a complex physiological process that begins during intrauterine life, extending to around eight years of age, and can be affected by numerous internal, external, natal and postnatal events. Abnormalities in any stage of development of the dental enamel may have repercussions in the form of permanent defects and marks clinically represented by the presence of grooves, depressions and diffuse or demarcated opacities, which can compromise function and esthetics. Thus, changes in the awake/sleep pattern can affect the tooth formation process. The hypothesis proposed in this paper is that changes in sleep and the circadian rhythm can affect the molecular bases involved in enamel formation either during the intrauterine period or in the first years of life, causing enamel anomalies. This is because the maternal circadian rhythm has a relationship with the circadian clock of their offspring, demonstrating numerous consequences of the imbalance in this relationship on the child's systemic and oral health. New perspectives with regards to oral outcomes may arise from this discussion, such as a greater importance placed on sleep quality in pregnant women and infants.

Cdc42 deletion yielded enamel defects by disrupting mitochondria and producing reactive oxygen species in dental epithelium

Developmental defects of enamel are common due to genetic and environmental factors before and after birth. Cdc42, a Rho family small GTPase, regulates prenatal tooth development in mice. However, its role in postnatal tooth development, especially enamel formation, remains elusive. Here, we investigated Cdc42 functions in mouse enamel development and tooth repair after birth. Cdc42 showed highly dynamic temporospatial patterns in the developing incisors, with robust expression in ameloblast and odontoblast layers. Strikingly, epithelium-specific Cdc42 deletion resulted in enamel defects in incisors. Ameloblast differentiation was inhibited, and hypomineralization of enamel was observed upon epithelial Cdc42 deletion. Proteomic analysis showed that abnormal mitochondrial components, phosphotransferase activity, and ion channel regulator activity occurred in the Cdc42 mutant dental epithelium. Reactive oxygen species accumulation was detected in the mutant mice, suggesting that abnormal oxidative stress occurred after Cdc42 depletion. Moreover, Cdc42 mutant mice showed delayed tooth repair and generated less calcified enamel. Mitochondrial dysfunction and abnormal oxygen consumption were evidenced by reduced Apool and Timm8a1 expression, increased Atp5j2 levels, and reactive oxygen species overproduction in the mutant repair epithelium. Epithelium-specific Cdc42 deletion attenuated ERK1/2 signaling in the labial cervical loop. Aberrant Sox2 expression in the mutant labial cervical loop after clipping might lead to delayed tooth repair. These findings suggested that mitochondrial dysfunction, up-regulated oxidative stress, and abnormal ion channel activity may be among multiple factors responsible for the observed enamel defects in Cdc42 mutant incisors. Overall, Cdc42 exerts multidimensional and pivotal roles in enamel development and is particularly required for ameloblast differentiation and enamel matrix formation.