Drugs related to the etiology of molar incisor hypomineralization: A systematic review

Molar Incisor Hypomineralization: Optimizing Treatment Protocols for Hypersensitivity: A Randomized Clinical Trial

Dentin hypersensitivity (DH) is a common challenge in pediatric patients with molar incisor hypomineralization (MIH), stemming from enamel porosity or exposed dentin after enamel breakdown. This three-arm randomized controlled clinical trial aims to evaluate the effectiveness of three different desensitizing treatment protocols. The study was conducted on 39 children, aged 6-14 years old, with MIH and DH. Group A received casein phosphopeptide plus amorphous calcium phosphate fluoride (CPP-ACPF) mousse and sham light therapy, Group B received placebo mousse and photo-bio-modulation therapy (PMBT), and Group C received both CPP-ACPF mousse and PMBT. DH evaluation using a visual analogue scale was performed at multiple time points. Both CPP-ACPF mousse and PMBT individually demonstrated desensitizing effects on dental elements affected by MIH. While PMBT had a greater immediate effect, the combination of the two therapies proved most effective in reducing DH. The VAS scores were statistically lower in group C compared to groups A and B, both after the first session (p = 0.0001) and after 28 days (p = 0.0005). This study suggests promising avenues for managing DH in MIH patients, highlighting the potential of combined therapies, specifically CPP-ACPF mousse and PMBT, for enhanced clinical outcomes.

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

BACKGROUND

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.

METHODS

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.

RESULTS

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]).

CONCLUSIONS

This study suggests that cesarean-section delivery and sixth disease (roseola) might increase the likelihood of MIH development in children.

Prevalence and severity of molar-incisor hypomineralization, is there an association with socioeconomic status? A cross-sectional study in Chilean schoolchildren

PURPOSE

Data about molar-incisor hypomineralization (MIH) prevalence and its severity remains limited for some Latin American countries. Furthermore, its association with socioeconomic status (SES) is still unclear. Thus, this study aims to determine the prevalence and severity of MIH in Santiago, Chile and explore its association with SES.

METHODS

A cross-sectional study with schoolchildren between 6 and 12 years was conducted. Children were evaluated using the European Academy of Paediatric Dentistry to diagnose MIH, and the Mathu-Muju and Wright criteria to determine its severity.

RESULTS

A total of 1,270 children were included. The MIH prevalence was 12.8% without association with gender (p = 0.609). Prevalence was higher among schoolchildren ages 8 and 9 (p = 0.002), and in lower SES (p = 0.007). MIH mild cases were the most prevalent (63%), and severity was not related to gender (p = 0.656), age (p = 0.060), or SES (p = 0.174).

CONCLUSIONS

The prevalence of MIH in the province of Santiago, Chile is 12.8% and was found to have a higher incidence in 8-9-year-old students and among those categorized by low SES. Furthermore, MIH prevalence was associated with low SES.

IMPLICATIONS

Public health policies to address MIH in Chile should start with schoolchildren aged 8 to 9, and with low SES.

Insights into molar-incisor hypomineralisation in past populations: A call to anthropologists

OBJECTIVE

Molar incisor hypomineralisation (MIH) is a developmental defect of enamel affecting the first permanent molars and often the incisors and affecting approximately 13% of the current population worldwide. Here, we aim to highlight potential differential diagnoses of MIH in archaeological collections (taphonomic discoloration, amelogenesis imperfecta, fluorosis, rachitic teeth, etc.).

METHODS

Causative factors of dental discolourations are identified through a literature review.

RESULTS

In an archaeological context, the sediments contained in the burial soil can lead to tooth discoloration. Taphonomic staining of the dentition may have a similar appearance to enamel hypomineralisation, and thus is a confounding factor that has the potential to cause miscalculation of the true prevalence of MIH within archaeological collections. Some rare medieval cases are reported in the modern literature but without microanalysis, misdiagnosis is possible. The aetiological factors of MIH are unknown but probably follow the multifactorial model involving systemic medical and genetic factors.

CONCLUSIONS

Systematic detection and diagnosis of MIH during anthropological studies is therefore of great interest.

SIGNIFICANCE

The hypotheses that only contemporary agents are causative factors of MIH could be refuted by the discovery of individuals living before medication or pollutants. The identification of MIH in a group of individuals also provides information regarding the health status of a population and reflects stress occurring during the period of mineralisation of the first permanent molars after secretion of the enamel matrix.

LIMITATIONS

Taphonomic alterations of archaeological remains prevent MIH diagnosis.

SUGGESTIONS FOR FUTURE RESEARCH

MIH diagnosis can be difficult in archaeological series and further non-destructive methods (microtomography, elemental analyses, etc.) are required.

Molar-incisor hypomineralisation prevalence in a cohort of Australian children with type 1 diabetes

PURPOSE

Systemic diseases or drugs administered early in life may cause a disruption in amelogenesis and contribute to the qualitative defect of enamel described as molar-incisor hypomineralisation (MIH). Therefore, an increase in prevalence of MIH in children with type 1 diabetes (T1D) may be expected as this systemic disorder is commonly diagnosed in early childhood. The aim of this study was to determine the prevalence of MIH in a cohort of children with T1D and investigate diagnosis of MIH with T1D factors.

METHODS

Cross-sectional study of children with T1D recruited from paediatric diabetes clinics at the Women's and Children's Hospital (South Australia). A detailed medical history, comprehensive dental and MIH examination according to the European Academy of Paediatric Dentistry (EAPD) long form classification was collected for each child. All upper and lower first permanent molars and central incisors were scored.

RESULTS

A total number of 73 participants; 35 (47.95%) males were examined including 584 teeth. The mean age of the participants was 13.25 ± 2.58 years, with a mean age of diagnosis 7.75 ± 3.58 years, and a mean HbA1c of 8.5 ± 1.6%. 42 out of 73 children (54.8%) had enamel defects on at least one of the teeth examined. However, 19.2% met the criteria for MIH. Univariate and bivariate analyses were conducted but no significant associations were noted between MIH and risk factors including diabetes control (p > 0.1).

CONCLUSION

There was a high prevalence of enamel defects and MIH amongst children with T1D. More research is required to establish association between T1D and MIH.

Association between respiratory diseases and molar-incisor hypomineralization: A systematic review and meta-analysis

The molar-incisor permineralização (MIH) is a qualitative enamel developing abnormality involving the occlusal and/or incisal third of one or more molars or permanent incisors, caused by systemic factors. Several systemic disorders and environmental factors, such as respiratory diseases, have been reported as probable causes of MIH. Thus, this work aimed to evaluate whether respiratory diseases and MIH are associated. The searches were carried out in electronic databases, including PubMed, Scopus, Web of Science, the Cochrane Library, LILACS, OpenGrey, and Google Scholar. The acronym PECO was used, in which the P (population) was humans in permanent dentition stage; (E-exposure) molar-incisor hypomineralization; (C-comparison) reference population and (O - outcome) respiratory diseases. After the search retrieval, the duplicates were removed, and the articles were evaluated by title and abstract; then, the papers were read and thoroughly assessed. After selection, the risk of bias assessment was performed using the Newcastle-Ottawa Scale (NOS) for observational studies. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) tool was used to assess the level of evidence. Three thousand six hundred and sixty six were found through the searches. After exclusion by duplicates, title, abstract, and full-reading, 13 articles remained. The articles included in this review evaluated the association of MIH with asthma, tonsilitis, pneumonia, and bronchitis. Most reports showed a low risk of bias. When exploring through GRADE, a very low level of evidence was found. We observed that the included studies showed that children with MIH had more respiratory diseases than the group that did not have MIH.

Systematic review registration

https://osf.io/un76d.

Etiology Study of Acquired Developmental Defects of Enamel and Their Association with Dental Caries in Children between 3 and 19 Years Old from Dolj County, Romania

Background: Developmental defects of enamel (DDE) are frequently encountered in primary and permanent teeth, yet their etiology is not completely known. Enamel hypoplasia is considered a predisposing factor for early caries. The objective of this study was the evaluation of several risk factors potentially causing DDE and the possible association between DDE and dental caries. Methods: This study was performed on a group of 213 rural children from Romania. It combined a thorough dental examination for all children, and a questionnaire filled in by their mothers, regarding the evolution of their pregnancy and the child’s health status in the first years of life. Results: There was no statistically significant association between DDE presence and data regarding the evolution of pregnancy, mothers’ health status or children’s conditions during early childhood. There was a significant association between the use of amoxicillin, ibuprofen, and cephalosporin during the period of formation of permanent teeth, and one environmental factor (water source), and the presence of DDE (Chi Square, p < 0.05). Also, DDEs were associated with the presence of caries (Fisher, p = 0.001). Conclusions: Children who consumed water from private wells and children who received medication during early childhood developed more enamel defects, presenting a higher risk of caries development.

Prevalence and Possible Etiological Factors of Molar-Incisor Hypomineralization (MIH) in Population of Silesian Children in Poland: A Pilot Retrospective Cohort Study

(1) Background: This pilot retrospective cohort research study regarded the frequency of the prevalence of molar-incisor hypomineralization (MIH) in a population of Silesian children in Poland. The evaluation of the potential environmental etiological factors was performed and the correlation between the environmental factors and MIH was analyzed. (2) Methods: A total of 613 children were randomly enrolled in the pilot study (9.0 years ± 1.9). A survey was carried out with mothers regarding the potential exposure to environmental etiological factors of MIH in their children. The patients’ clinical assessments were carried out in the dental unit. (3) Results: The frequency of prevalence of MIH in the population of Silesian children was established at the level of 6.2% (p < 0.05). MIH symptoms were significantly associated with otitis in early childhood (OR = 2.50), atopic dermatitis (OR = 5.69), and premature delivery before 38 weeks of pregnancy (OR = 2.88). (4) Conclusions: MIH was observed in 6.2% of the population of Silesian children, and there was a relationship between environmental risk factors such as otitis, atopic dermatitis, premature birth, and MIH expression. Therefore, further research is needed to determine the influence of pre-, peri-, postnatal, and prophylactic factors on the frequency and severity of MIH symptoms in children.

Are yellow-brownish opacities in hypomineralized teeth more prone to breakage than white-creamy ones? A systematic review

OBJETIVE

To evaluate all the available evidence assessing if in hypomineralized teeth, yellow-brownish opacities are more prone to post-eruptive breakdown (PEB) compared to white-creamy opacities.

MATERIALS AND METHODS

Observational studies that evaluated the occurrence of PEB in hypomineralized teeth were considered for inclusion. Electronic searches were performed up to January 2022 in MedLine, LILACS, BBO, Cochrane Library, Web of Science, Scopus, and EMBASE. Neither publication date nor language restrictions were imposed to the searches. Two researchers independently performed the study selection, data extraction, and quality assessment of the included studies according to the Newcastle-Ottawa Scale (NOS). Datasets from studies were grouped for narrative synthesis based on the severity of the PEB (enamel or dentin), type of tooth (molar or incisor), unit of analysis (subject or tooth or tooth surface), and follow-up period (in months). The certainty of evidence was evaluated using the GRADE approach.

RESULTS

Nine studies were included, five cohort and three cross-sectional. All studies assessed the opacities and PEB by visual examination and diagnosed MIH according to EAPD criteria. In the cohort studies, considering all follow-up periods (ranging from 6 to 36 months), dark opacities fractured more than light opacities, at both enamel and enamel/dentin levels, and molars fractured more than incisors. In two out of three cross-sectional studies, dark opacities also fractured more than light opacities, but the deep of the PEB (enamel or dentin breakdown) or the type of tooth (molar or incisor) was not considered in the analysis.

CONCLUSION

Although it seems plausible to state that darker demarcated opacities in MIH patients broke more often than light ones, based on this systematic review of the literature, the certainty of the available evidence about this association is still very low.

CLINICAL RELEVANCE

More reliable and valid research is still necessary to support any future recommendation that MIH children who present yellow-brownish opacities should be monitored at shorter intervals compared to those who present only white-creamy opacities.

An update of the aetiological factors involved in molar incisor hypomineralisation (MIH): a systematic review and meta-analysis

PURPOSE

To systematically review the aetiological factors associated with molar incisor hypomineralisation (MIH). To this day, the aetiology remains unknown. Determining risk factors would allow risk assessment and enhance early diagnosis of MIH in young patients. The aim was to assess, evaluate and summarise the relationship between MIH and reported aetiological hypotheses.

METHODS

Electronic database searches of MEDLINE, EMBASE, EBSCO, LILACS and Cochrane Library were conducted. Authors conformed to PRISMA guidelines. Studies were screened, data extracted, assessment of risk of bias and calibration was completed by two independent reviewers. Meta-analyses with heterogeneity calculations were performed.

RESULTS

Of the potential 8949 studies, 64 studies were included in the qualitative analysis whilst 45 were included in the quantitative analysis. Prenatal factors: results are inconclusive as only unspecified maternal illnesses appear to be linked to MIH. Perinatal factors: prematurity (OR 1.45; 95% CI 1.24-1.70; p = 0.0002) and caesarean delivery (OR 1.45; 95% CI 1.09, 1.93; p < 0.00001) are associated with an increased risk of developing MIH. Birth complications are also highlighted. These three factors can lead to hypoxia, and children with perinatal hypoxia are more likely to develop MIH (OR 2.76; 95% CI 2.09-3.64; p < 0.0001). Postnatal factors: measles, urinary tract infection, otitis media, gastric disorders, bronchitis, kidney diseases, pneumonia and asthma are associated with MIH. Fever and antibiotic use, which may be considered as consequences of childhood illnesses, are also associated with MIH. Genetic factors: an increasing number of studies highlight the genetic and epigenetic influences in the development of MIH.

CONCLUSION

Several systemic and genetic and/or epigenetic factors acting synergistically or additively are associated with MIH, revealing a multifactorial aetiology model. Peri- and postnatal aetiological factors are more likely to increase the odds of causing MIH than prenatal factors.

A case-controlled investigation of risk factors associated with molar incisor hypomineralization (MIH) in 8-12 year-old children living in Chandigarh, India

PURPOSE

Despite mounting evidence in favour of various perinatal risk factors for occurrence of MIH, verification of these remains doubtful because of lack of documented proof. The present study was aimed at examining the putative risk factors for MIH based on hospital-maintained records assessment.

METHODS

A total of 3176, 8-12 year-old children were screened for MIH using EAPD criteria (2003). Of these, risk factor analysis was carried out for 104 MIH affected and 211 non-MIH affected children with complete peri-natal medical records maintained up to 3 year post-birth. Chi-square test was used for risk factor comparison, while significance was assessed using logistic regression.

RESULTS

Prevalence of MIH in study population was 11.72% (372/3176). Various pre-natal, natal and post-natal risk factors including intra-uterine growth retardation (6.7 vs. 1.4%); maternal anaemia (10.6 vs. 3.8%) and neonatal jaundice (29.8 vs. 14.2%) were significantly higher in the MIH group. Furthermore, pre-term birth (OR 3.01), low birth weight (OR 2.37), more than three pyrogenic episodes (OR 7.61) and consumption of Amoxicillin Clavulanate (OR 3.01) were significantly associated with higher risk of developing MIH.

CONCLUSIONS

Pre and post-natal risk factors showed a moderate to high association for occurrence of MIH although social and nutritional factors had a lesser association.

Effects of antibiotics on the developing enamel in neonatal mice

PURPOSE

Identifying factors causing Molar-Incisor Hypomineralization (MIH) is an ongoing challenge. Preterm infants, routinely treated with antibiotics in cases of suspected sepsis, are more commonly affected by dental developmental defects. This study aimed to investigate the effects of gentamycin and ampicillin on the developing enamel in neonatal CD-1 mice in vivo.

METHODS

Neonatal mice were randomized into a study (n = 36) and a control (n = 35) group. Antibiotics were injected intravenously for 4 days. All mice were sacrificed after 15-18 days. Micro-CT was used to analyse the mineral density (MD) of the enamel and the proportion of the enamel object volume (vol%) in first molars and incisors.

RESULTS

We demonstrated a significantly lower vol% enamel in the maxillary (30.9% vs. 32.7%; p = 0.004) and mandibular (32.5% vs. 34.6%; p = 0.015) molars in the study group than in the controls. The incisors were divided into segments upon analysis. We demonstrated both lower vol% and lower MD of the enamel in most segments in treated individuals compared to controls (p < 0.05).

CONCLUSION

The reduced MD and vol% in the molars and incisors are likely to have been caused by the antibiotics given during tooth development. The presented analysis of teeth in neonatal mice with micro-CT could be a valid model for further research on dental developmental defects.

Factors and Mechanisms Involved in Acquired Developmental Defects of Enamel: A Scoping Review

BACKGROUND

Developmental Defects of Enamel (DDE) is a pathology of the teeth that can greatly alter the quality of life of patients (hypersensitivity, esthetic issues, loss of function, etc.). The acquired DDE may occur as a result of a wide range of acquired etiological factors and his prevalence of this pathology may reach up to 89.9%. The main objective of this research was to identify and analyze, in current literature, the factors related to acquired DDE, in order to propose a general theory about the mechanisms involved.

METHODS

The search of the primary literature was conducted until [December 31, 2021]. Our search strategy uses the Pubmed/MEDLINE database and was structured around 3 terms ["Development," "Defect," and "Enamel"]. To be included, references had to be primary studies, written in English. Exclusion criteria were reviews, in vitro, animal, genetic or archeology studies, and studies focused on clinical management of DDE. One hundred and twenty three articles were included in this scoping review: 4 Randomized clinical trials, 1 letter, 5 cases reports, 2 fundamentals studies, and 111 observational studies (33 Cross-sectional studies, 68 Cohort study and 10 Case-control study). The quality of evidence was assessed using the PEDro scale for clinical trials, the Newcastle-Ottawa scale for observational studies, and a published tool to assess the quality of case reports and case series.

RESULTS

A scoping review of the literature identified 114 factors potentially involved in acquired DDE. The most frequently encountered pathologies are those causing a disorder of calcium homeostasis or a perturbation of the ARNT pathway in mother or child. The link between the ARNT pathway and metabolism deficiency in uncertain and needs to be defined. Also, the implication of this mechanism in tissue impairment is still unclear and needs to be explored.

CONCLUSIONS

By identifying and grouping the risk factors cited in the literature, this taxonomy and the hypotheses related to the mechanism allow health practitioners to adopt behaviors that limit the risk of developing aDDE and to set up a prevention of dental pathology. In addition, by reviewing the current literature, this work provides guidance for basic research, clinical studies, and literature searches.

Molar-incisor hypomineralization: an umbrella review

OBJECTIVE

In recent years, Molar Incisor Hypomineralization (MIH) has become a subject that concerns the Paediatric Dentistry Community. The aim of the present umbrella review was to analyse previously published systematic reviews (SRs) on MIH in children and adolescents.

METHODS

Electronic database search was conducted (including PubMed, Embase, Scopus, Cochrane, Web of Science, and LILACS) until July 2020. Studies were included, if they were SR on MIH in children and adolescents. The methodological quality of SRs was judged by use of the MeaSurement Tool to Assess systematic Reviews 2. The primary outcomes included prevalence, aetiology, and clinical management of MIH. Data extraction and methodological quality assessment were performed.

RESULTS

Eighteen systematic reviews were included for data extraction. Among these, two were focussing on prevalence, five addressed aetiology, one highlighted the mechanical and chemical characteristics of enamel in MIH, one underlined the association between MIH and dental caries, six addressed the treatment, and one focussed on hypomineralization of primary teeth as a predictor of MIH. The results showed a high worldwide prevalence of MIH and an unknown aetiology of MIH, but reporting that the aetiology is most likely multifactorial. Different treatment approaches used were desensitizing and remineralizing products, resin infiltration, fissure sealant, atraumatic restorative treatment, resin composite restoration, and stainless steel crown (SSC), but also extraction associated with orthodontic treatment of the permanent first molars (PFMs) was reported on. The AMSTAR criteria 2 was applied, where six studies were assessed as having critically low quality, two studies as having low quality, and nine studies as having moderate quality.

CONCLUSIONS

MIH is highly prevalent worldwide and has most likely a multifactorial aetiology. Different treatment approaches according to the degree of severity of lesion(s) are reported on. The quality of evidence produced by the available SRs was not favourable. More well-designed clinical trials and high standard systematic reviews are necessary to elucidate better MIH characteristics and treatment outcomes.

Etiology of Molar-Incisor Hypomineralization (MIH): A Cross-Sectional Study of Saudi Children

(1) Background: Molar-incisor hypomineralization (MIH) is a common clinical condition with critical negative consequences for dental health. The etiology of MIH is still not completely understood, although several theories have been suggested. (2) Aim: To investigate the etiology of MIH defects in a sample of Saudi school children. (3) Method: A total of 893 school children in the age range of 8–10 years participated in the study. The sample was taken from Riyadh City, Saudi Arabia. The participating children were examined for MIH using the European Academy of Pediatric Dentistry Criteria. The children’s parents were asked about the child’s pre, peri-, and postnatal condition utilizing a structured and validated questionnaire. (4) Results: A total of 362 children (168 males and 194 females) were affected with MIH, for a prevalence of 40.5%. Among all analyzed etiological factors, only jaundice was found to be significantly associated with MIH in children (OR = 1.35, p = 0.047). Multivariate logistic regression analysis confirmed that the only significant etiological factor for MIH was newborn jaundice (p = 0.04). (5) Conclusion: Newborn jaundice was the only etiological factor that showed a significant association with MIH in the studied Saudi school children.

Molar Incisor Hypomineralization (MIH) in a Child with Congenital Chronic Intestinal Pseudoobstruction (CIPO)

Molar incisor hypomineralization (MIH) is a qualitative enamel defect of systemic origin affecting 1-4 permanent first molars (PFMs) frequently in association with affected permanent incisors (PIs). The exact etiology of MIH is still unclear but considered to be multifactorial. This present case report to the best of our knowledge is the first case reported which acknowledges MIH in a patient with chronic intestinal pseudoobstruction (CIPO) with underlying neurological disease due to somatic mitochondrial disorder. It also elicits the availability of various contemporary treatment options and their proper selection and early intervention to manage the functional and aesthetic problems caused by enamel defects and to improve the quality of life in the patients.

Molar-incisor hypomineralization in quilombola children and adolescents: A study of prevalence and associated factors

OBJECTIVES

This cross-sectional observational study determined the prevalence and factors associated with molar-incisive hypomineralization (MIH) in quilombola children and adolescents in north-eastern Brazil.

METHODS

The sample consisted of 251 children and adolescents (8 to 14 years old) living in the rural quilombola community Lagoas in São Raimundo Nonato, Piauí (census population). Sociodemographic and health-related data were collected from pre-, peri- and post-natal health records and a clinical examination for MIH diagnosis was performed by four previously trained and calibrated examiners. Descriptive data analysis and Poisson regression were performed. The magnitude of the association was determined by adjusted prevalence ratio (PR) and confidence intervals (95% CI).

RESULTS

The prevalence of MIH was 46.6%. The presence of MIH was associated with gestational diabetes (PR = 2.49, 95% CI 2.08-2.99; p <0.001) and acute foetal distress (PR = 1.39; 95% CI 1.04-1.86; p = 0.025).

CONCLUSION

It was concluded that the prevalence of MIH in the quilombola community was high and associated with gestational diabetes and acute foetal distress.

Perception, knowledge, and attitudes towards molar incisor hypomineralization among Spanish dentists: a cross-sectional study

BACKGROUND

Molar incisor hypomineralization (MIH) is a growing health problem, and its treatment is a challenge. The purpose of the present study was to evaluate and compare the perceptions, knowledge, and clinical experiences of MIH in general dental practitioners (GDPs) and paediatric dentists (PDs) in Spain.

METHODS

All dentists belonging to the College of Dentists of the Region of Murcia, in the South-East of Spain, were invited to participate in a cross-sectional survey. They were asked to complete a two-part questionnaire including sociodemographic profiles and knowledge, experience, and perceptions of MIH. Data were analysed using Pearson's chi-square test, Fisher's exact test and Cramer's V test.

RESULTS

The overall response rate was 18.6% (214/1147). Most respondents were aged 31-40 years (44.86%), with more than 15 years of professional experience (39.72%). They worked mainly in the private sector (84.58%) and were licensed in dentistry (74.30%): 95.45% of PDs had detected an increase in the incidence of MIH in recent years (p <  0.001). Only 23.80% of GDPs claimed to have made a training course on MIH. With respect to the aetiology, chronic medical conditions (p = 0.029) and environmental pollutants (p = 0.008) were the only factors that showed significant between-group differences. Durability (p = 0.009) and remineralization potential (p = 0.018) were the factors where there was a between-group difference in the choice of the restoration material. In the case of post-eruptive fractures and opacities, the preferred material for both groups was resin-modified glass ionomer (RMGIC). However, in incisor lesions, composite was the material of choice for both groups, with significant differences (p = 0.032) in the use of glass ionomer. Most respondents expressed a need for continuing education on MIH.

CONCLUSION

Spanish dentists perceived an increase in the incidence of MIH. The material of choice was RMGIC for non-aesthetic sectors and composite for incisors. Dentists believe it is difficult or very difficult to manage MIH, since the long-term success of restorations of MIH lesions is compromised because resin adhesion is not good. Both GDPs and PDs believe they need more training on the aetiology, diagnosis, and treatment of MIH.

MOLAR INCISOR HYPOMINERALIZATION AND CELIAC DISEASE

BACKGROUND

Molar incisor hypomineralization (MIH) is a developmental enamel defect with multifactorial etiology. Although the relationship between celiac disease (CD) and developmental enamel defect was demonstrated, the association between CD and MIH is uncertain.

OBJECTIVE

The objective of this study was to analyze the occurrence of MIH in CD patients.

METHODS

Forty CD patients and a control group with 40 healthy individuals were selected. A calibrated examiner (k≥0.889) according to the European Academy of Pediatric Dentistry criteria performed the diagnosis of MIH. Data were analyzed by descriptive statistics and Fischer's exact test (α=0.05).

RESULTS

Of the 80 participants, ten presented MIH with eight individuals with CD. Celiac patients presented 4.75 times the chance of occurrence of MIH than the control group (95% CI: 2.22-10.18; P=0.044). In all the evaluated teeth (n=978), 22 had MIH: 20 teeth in individuals with CD and two in those without the disease. All CD participants with MIH presented the classic form of the disease. CD participants showed 17 teeth (85.0%) with demarcated opacities, two (10.0%) post-eruptive collapses and one (5.0%) atypical restoration. The control group presented only demarcated opacities.

CONCLUSION

CD increased the chance of MIH and associated with its clinical manifestations can assist in the diagnosis of CD.

The possible influence of genetic aetiological factors on molar-incisor hypomineralisation

OBJECTIVE

The present study searched for evidence of possible associations between some genetic factors that could affect the development of molar-incisor hypomineralisation (MIH).

METHODS

In 113 patients who were surgically treated at an Otorhinolaryngology and Cervicofacial Surgery Clinic (ORL) during early childhood, human leukocyte antigen (HLA) DQ2 and DQ8 haplotypes and single nucleotide polymorphisms (SNP) of eight amelogenesis-related genes were searched in genomic DNA. Genotypes were determined by high resolution melting (HRM), TaqMan genotyping assays, and Sanger sequencing. Association between MIH and the HLA DQ2 and DQ8 alleles was tested using a univariate logistic regression. The significance of genetic variants was analysed using the Cochran-Armitage tests for trend and the Fisher exact tests.

RESULTS

We identified MIH in 22 (19.5 %) of the 113 children. Among the evaluated genetic variants, SNP rs2245803 in the MMP20 gene in a homozygous form in a recessive model was associated with MIH development (OR, 2.796; 95 %CI, 1.075 - 4.783; p = 0.0496) with the genotype distribution of TT(3), TG(6) or GG(13) in children with MIH and distribution of TT(18), TG(42) or GG(31) in children without MIH.

CONCLUSIONS

While the aetiology of MIH remains unclear, our findings suggest that variants of genes associated with amelogenesis may play important roles in susceptibility to MIH.

Molar Incisor Hypomineralization: Etiology, Clinical Aspects, and a Restorative Treatment Case Report

CLINICAL RELEVANCE

Total-etch adhesive systems and resin composite are clinically viable dental materials for esthetic restorations in teeth presenting white/yellow/brown hypomineralization stains.

SUMMARY

Molar-incisor hypomineralization (MIH) is a condition that negatively affects enamel and dentin, especially the first molars and permanent incisors, causing esthetic and functional problems. The present clinical case report presents and discusses the etiology and clinical characteristics of MIH and describes a restorative protocol for MIH-affected teeth.

Aesthetic perception in children with molar incisor hypomineralization

PURPOSE

To investigate the relationship between aesthetic perception and molar incisor hypomineralization (MIH) in schoolchildren aged 8-12 years.

METHODS

The study included 467 pupils enrolled in elementary schools. Once authorization was received, the students were examined for DMFT and dmft indexes (WHO criteria), and for MIH (EAPD criteria). The aesthetic perceptions were verified by the Child Perceptions Questionnaire About Tooth Appearance (CQATA), a questionnaire divided into several items, including physical, psychological and social domains; perception about tooth pleasantness, tooth alignment, tooth discoloration and tooth health; and reported pleasant colour. Data analysis was carried out using descriptive statistics, the Chi-square, the Mann-Whitney and the Kruskal-Wallis tests, and linear regression at a significance level of 0.05.

RESULTS

The tooth health perception was worse when the child had MIH, and the tooth alignment and tooth discoloration perceptions, when MIH affected the incisors. The number of teeth affected by MIH was associated with higher averages in the tooth discoloration perception.

CONCLUSIONS

Children with MIH showed more negative perceptions toward tooth health, tooth alignment and tooth discoloration. However, none of the clinically investigated variables negatively impacted the reported pleasant colour question.

[Oral cavity as a target and a marker of environmental exposures: developmental dental defects]

The oral cavity is one of the main route for environmental contaminations associated to many chronic diseases (cancers, fertility and behavior disorders for example) via alimentation, medications and respiration. These environmental factors including, among others, endocrine disruptors and excessive fluoride can disrupt dental development and thus generate irreversible enamel defects. These defects are then treated with materials that may release molecules capable of generating these defects, leading to a vicious circle, particularly in pregnant women and young children. The present paper aims to review the state of knowledge, questions and controversies on common environmental factors in contact with the oral cavity. It also reviews their mechanisms of action and the mediators involved in enamel pathologies associated with environmental conditions. Dental tissues can not only be targeted by environmental factors but can also serve as early and easily accessible markers of exposure to these agents. Understanding and characterizing the environmental impact in the oral cavity will help to prevent multiple diseases, oral and distant, whose link with oral homeostasis is just being explored.

Are the Internet users concerned about molar incisor hypomineralization? An infoveillance study

BACKGROUND

Molar incisor hypomineralization (MIH) is a developmental enamel defect characterized by well-demarcated discolorations frequently detected in molars, causing pain and esthetic alterations.

AIM

To assess the interests of Google users on MIH-related information.

DESIGN

Digital data were collected in Google Trends through two search strategies, 'molar incisor hypomineralization' (topic) and 'MIH' (search term), between January 2004 and November 2018. ARIMA models were applied to analyze trends of curves and to predict the activity of Google users during 12 months. Autocorrelation and partial autocorrelation (ACF/PACF) plots were used to detect trends in the variation of relative search volume (RSV) related to search strategies over time. The most popular queries were analyzed qualitatively, whereas geographical heat maps were retrieved to determine search volumes according to countries (P < .05).

RESULTS

Gradual increasing trends were detected, with forecasts indicating similar levels of RSVs to the period between December 2017 and November 2018. Most popular queries and topics were associated with MIH diagnosis, being retrieved predominantly in European countries.

CONCLUSIONS

The activity of Google users related to this condition is maintained low, with a reduced intensification over time, suggesting that the awareness on MIH is probably confined to dentists and affected people worldwide.

Infantile hemangioma of the upper lip and enamel hypoplasia: Two case reports

Segmental infantile hemangiomas related to PHACE syndrome have recently been associated with enamel hypoplasia. We present two cases of solitary, localized upper lip infantile hemangioma with enamel hypoplasia of deciduous teeth.

A systematic review and meta-analysis of systemic exposure associated with molar incisor hypomineralization

OBJECTIVE

To evaluate systemic exposures associated with molar incisor hypomineralization (MIH).

METHODS

This systematic review was performed using published observational studies that evaluated the systemic exposures associated with MIH. The sources of articles searched were PubMed, Scopus, Web of Science, LILACS, BBO, Cochrane Library and Grey literature. The risk of bias was analysed according to the Newcastle-Ottawa Scale for quality assessment. The meta-analysis was performed considering the exposures during the prenatal, perinatal and postnatal periods using the CMA software.

RESULTS

A total of 4207 articles were identified. Twenty-nine studies were eligible for inclusion and 27 were included in the meta-analysis. The studies presented low and moderate risks of bias, except for one that was classified as having a high risk of bias. Maternal illness during pregnancy (OR 1.40; 95% CI 1.18-1.65, P < 0.0001) and psychological stress (OR = 2.65; 95% CI 1.52-4.63; P = 0.001) was observed to be significantly associated with higher odds of MIH. During the perinatal period, caesarean delivery (OR = 1.32, 95% CI 1.11-1.57, P = 0.001) and delivery complications (OR = 2.06; 95% CI 1.47-2.88, P < 0.0001) were also associated with MIH. In the postnatal period, only respiratory diseases (OR = 1.98; 95% CI 1.45-2.70, P < 0.0001) and fever (OR = 1.50; 95% CI 1.22-1.84; P < 0.0001) were associated with higher prevalence of MIH. The evidence was graded as very low quality.

CONCLUSIONS

Maternal illness, psychological stress, caesarean delivery, delivery complications, respiratory diseases and fever during the first years of a child's life were significantly associated with a higher odds of MIH. However, this should be interpreted with caution, once the primary studies were observational, with serious limitations according to the risk of bias, imprecision, and inconsistency. Further, well-designed cohort studies are still required.

Effect of antibiotics and NSAIDs on cyclooxygenase-2 in the enamel mineralization

The objective of this study was to determine whether the use of the most commonly prescribed antibiotics and non-steroidal anti-inflammatory drugs in childhood could disturb enamel mineralization. Forty-two Swiss mice were divided into seven groups: controls; amoxicillin; amoxicillin/clavulanate; erythromycin; acetaminophen; ibuprofen and celecoxib, to inhibit cyclooxygenase 2 (COX2). SEM-EDX analysis was conducted on all cusps of the third molars. Calcium (Ca), phosphorus (P), aluminum, potassium, sodium, magnesium and chlorine were quantified. The stoichiometric Ca/P molar ratios were calculated. Immunohistochemical quantification of COX2 in incisors was carried out by image analysis using COX2-specific immunostaining. Groups treated with antibiotics showed no significant differences in the content of the chemical elements. Only acetaminophen and celecoxib showed a significant decrease in Ca and P compared with the control samples. Ca/P ratios showed no difference. Groups treated with amoxicillin, amoxicillin/clavulanate, erythromycin and acetaminophen showed significantly lower amounts of immunoreactive COX2 at the enamel organ maturation stage of the mouse incisors. Our results suggest that COX2 is involved in the maturation stage of the enamel organ and that its inhibition would appear to alter amelogenesis, producing hypomineralization.

Exploring the association between genetic and environmental factors and molar incisor hypomineralization: evidence from a twin study

BACKGROUND

The etiology of molar-incisor hypomineralization (MIH) remains unknown. Studies indicate that it is multifactorial, and that genetic and environmental factors are involved. Research with twins provides important subsidy to investigate the Influence of genetics and environmental factors that act during pregnancy on the etiology of alterations.

AIM

This cross-sectional study evaluated the agreement of molar incisor hypomineralization (MIH) between monozygotic and dizygotic twin pairs and the association with environmental factors.

DESIGN

The sample consisted of 167 pairs of twins (8-15 years old), 94 monozygotic and 73 dizygotic. The parents answered a questionnaire on sociodemographic data and pre-, peri-, and postnatal health. A dental examination was performed by two calibrated examiners (Kappa ≥0.88) for MIH diagnosis, following the criteria proposed by the European Academy of Pediatric Dentistry in 2003.

RESULTS

The prevalence of MIH was 29.3%. There was greater concordance of MIH between monozygotic twins for affected first molars and permanent incisors (P = 0.0012) and pairs of twins assessed (P = 0.0211). The presence of MIH was associated with family income between one and two wages (P = 0.009, prevalence ratio [PR] = 3.82, confidence interval [CI 95%] 1.40-10.44), above two wages (P = 0.007, PR = 4.60, 95% CI: 1.51-14.05), and gestational hemorrhage (P = 0.032, PR = 5.70, 95% CI: 1.16-28.14).

CONCLUSIONS

The greater concordance in the diagnosis of MIH among monozygotic twins indicates a genetic influence, although environmental factors, such as family income and hemorrhage during pregnancy, are also associated with the occurrence of MIH.

Molar Incisor Hypomineralization and Its Prevalence

Background:

Molar incisor hypomineralization (MIH) is the hypomineralization of systemic origin of one to four permanent first molars, frequently associated with affected incisors. It is presented as demarcated enamel opacities of different colors, occasionally undergoing posteruptive breakdown. The characteristic feature of MIH is the clear demarcation between the affected and sound enamel. There is asymmetry of defects present in the molars and incisors where one molar or incisor can be severely affected, while the contralateral tooth may be clinically sound or have only minor defects.

Aim and Objective:

The aim of this study is to evaluate schoolchildren of 7–12 years of age with at least one of the first permanent molars fully or partially erupted from randomly selected government and private schools in Chennai using the European Academy of Pediatric Dentistry (EAPD) criteria for MIH, to determine the prevalence and characteristics of MIH.

Materials and Methods:

The dental examinations were performed in the classroom using a mouth mirror and explorer under a headlight. Teeth were wiped with gauze when necessary to remove plaque or the food accumulations. Surfaces that were examined were the buccal, lingual, palatal, and occlusal surfaces of permanent first molars and labial surfaces of upper and lower incisors. A single examiner was involved to avoid interexaminer bias. All the data were collected and scored using the EAPD criteria for MIH.

Results:

A total of 22 (12.9%) children out of the examined 170 had MIH.

Conclusion:

Distribution of MIH was more in males, more in 9 years of age. A total of 13 children had first molars affected and 9 children had both incisors and molars affected. Molars were affected more than the incisors. Mandible was affected more in comparison with the maxilla. Right side was affected more than the left side. The distribution of MIH was more in government schools compared to private schools.

Analytical evidence of enamel hypomineralisation on permanent and primary molars amongst past populations

Molar Incisor Hypomineralisation (MIH) and Hypomineralised Second Primary Molars (HSPM) involve prevalent qualitative structural developmental anomalies of tooth enamel affecting the first permanent molars (and often incisors) and the second primary molars, respectively. These demarcated hypomineralised lesions of enamel manifest as white-cream or yellow-brown opacities, with possible post-eruptive localised loss of enamel. Aetiological hypotheses have involved contemporary life factors (i.e. environmental pollutant exposure or early childhood medications) in contrast to factors not limited to a specific time period (i.e. hypoxia at birth or genetic predisposition). Evidence of MIH in ancient populations would reinforce aetiological factors present for many centuries. By means of microtomographic and X-ray fluorescence analyses the present study provides evidence that (i) two archaeological specimens: “S407” (Sains-en-Gohelle, France, 12^th–16^th centuries) and “B335” (Beauvais, France, 15^th–18^th centuries) were MIH-affected, and (ii) one individual “S323” was affected by HSPM and MIH (Sains-en-Gohelle, France, 7^th–11^th centuries).

Eighteen-month clinical performance of composite resin restorations with two different adhesive systems for molars affected by molar incisor hypomineralization

INTRODUCTION

The restorative management of molars with molar incisor hypomineralization (MIH) represents a challenge in the clinical practice with high failure rate.

OBJECTIVE

The aim of this study is to evaluate the clinical survival of direct composite resin restorations in first permanent molars (FPMs) that are affected by MIH, comparing two adhesive systems.

MATERIAL AND METHODS

We selected 41 FPMs with MIH from children aged 6-8 years. FPM fully erupted and with restorative treatment needed were the inclusion criteria. We excluded FPMs with destroyed crowns. The FPMs were randomly assigned to two groups: self-etching adhesive (SEA) and total-etch adhesive (TEA). Clinical evaluation was performed by a blinded examiner during 18 months according to the modified US Public Health Service (USPHS) criteria. The actuarial method was used to evaluate survival of the restorations, and Chi-square and Fisher's exact tests were used to compare differences between the groups (α = 5 %).

RESULTS

The cumulative survival rates were 100 % at 1 month, 89 % at 6 months, 73 % at 12 months, and 68 % at 18 months in SEA, and 95 % at 1 month, 72 % at 6 months, 59 % at 12 months, and 54 % at 18 months in TEA; there was no significant difference between groups.

CONCLUSIONS

There was no difference in clinical survival of restorations in FPMs affected by MIH using TEA or SEA adhesives in the end of 18 months.

CLINICAL RELEVANCE

It was suggested that SEAs as well as TEAs can be applied to restore molars affected by MIH, when it is performed a conservative cavity preparation. Once, cavosurface margins (cavity design) in hypomineralized enamel have less bonding capability.

On the Etiology of Molar-Incisor Hypomineralization

Molar-incisor hypomineralization (MIH) is a condition that is defined based on its peculiar clinical presentation. Reports on the etiology of the condition and possible risk factors are inconclusive and the original suggestion that MIH is an idiopathic condition is often cited. Our group was the first to suggest MIH has a genetic component that involves genetic variation in genes expressed during dental enamel formation. In this report, we provide a rationale to explain the preferential affection of molars and incisors. We suggest that MIH is a genetic condition based on its prevalence, which varies depending on the geographic location, and the evidence that on occasion second primary molars, permanent canines, and premolars can show signs of hypomineralization of enamel when molars and incisors are affected.