Do We Really Know the Prevalence of MIH?

Influence of maternal health status during pregnancy and the child´s medical history on molar-incisor hypomineralization in a group of Spanish children (aged 6-14 years): a retrospective case-control study

BACKGROUND

Molar-incisor hypomineralization (MIH) is a qualitative enamel defect that is highly prevalent in children. It has been reported that patients with MIH have higher caries occurrence with an increased need and frequency of dental treatment compared to patients without MIH. The objective of this study was to analyze the association between MIH and a series of factors related to maternal health status during pregnancy and children´s medical history in early childhood.

METHODS

A retrospective study of cases (patients with MIH) and controls (patients without MIH) was designed between 2023 and 2024. A total of 280 children (cases = 140; controls = 140) aged 6 to 14 years (138 boys and 142 girls) were examined according to the European Academy of Pediatric Dentistry (EAPD) criteria for MIH. A survey was carried out with mothers regarding the potential exposure of their children to etiological factors of MIH. Possible prenatal and postnatal etiological factors were obtained through a personal interview with the patients' mothers. The statistical analysis was carried out with the contrast test and the chi-square test.

RESULTS

During pregnancy, folic acid consumption, alcohol intake, systemic viral and/or bacterial infections, and gestational diabetes were statistically significantly related to MIH, as were breastfeeding, asthma, and corticosteroid consumption during childhood.

CONCLUSIONS

Although there are different factors that may have statistically significant relationships with MIH, they cannot be predicted. Therefore, longitudinal studies, with a large sample size, are needed to determine the influence of prenatal and postnatal factors on the prevalence and severity of MIH in children.

Evaluation of hard tissue characteristics and calcifications in pulp tissue of hypomineralized permanent molars using micro-computed tomography

OBJECTIVES

To determine and compare pulp volume, dentin mineral density, presence of microcracks, pulp stones, and accessory canals, as well as their localizations in root regions for hypomineralized and healthy teeth.

DESIGN

This study included 60 extracted permanent molar teeth, categorized into hypomineralized and healthy groups (n = 30 each). The hypomineralized group comprised molar teeth with limited white, yellow, or brown opacities, post-eruptive breakdown, or extensive restoration or crown damage. The healthy group included caries-free molar teeth without these characteristics. Using 3D micro-computed tomography images pulp volume, dentin mineral density, and the presence and locations of microcracks, pulp stones, and accessory canals were determined for each group. Statistical analyses were conducted using Independent T-test and Chi-square test, with significance set at p < 0.05.

RESULTS

There was no statistically significant difference between the groups regarding pulp volume and microcracks (p ≥ 0.05). The number of accessory canals was significantly greater in the cervical (p = 0.011; p < 0.05) and middle (p = 0.010; p < 0.05) regions of the hypomineralized teeth than healthy teeth. Dentin mineral density was statistically higher in the apical, middle, and cervical root regions (p < 0.001; p < 0.05); however, the number of pulp stones was found to be greater in the cervical regions of healthy teeth compared with those with hypomineralization (p = 0.026; p < 0.05).

CONCLUSION

There were lower dentin mineral density measurements, a decreased number of pulp stones in the cervical region, and a greater number of accessory canals in the middle and cervical regions of hypomineralized teeth compared with healthy teeth.

Which are the clinical consequences of Molar Incisor hypomineralization (MIH) in children and adolescents? Systematic review and meta-analysis

OBJECTIVE

This systematic review was conducted to address the following research question: "What are the clinical consequences (outcome) of Molar Incisor Hypomineralization (MIH) (exposure) in children and adolescents (population/patient)?".

MATERIAL AND METHODS

After defining the strategy, a search was performed in different databases (MEDLINE via Pubmed, Cochrane Library, BBO, LILACS, Scopus, Web of Science, Embase) and Grey literature in August 2023. Cross-sectional observational studies that identified clinical consequences of MIH (dental caries, post-eruptive structural loss, atypical restorations, hypersensitivity and tooth extraction) were included. The risk of bias was assessed following the Joanna Briggs Institute protocol for cross-sectional studies. Meta-analyses were conducted for each outcome, taking into account the number of patients and teeth. The effect measure considered was the prevalence; random-effects model was adopted. Heterogeneity was assessed using I2 statistics and prediction intervals (PI).

RESULTS

A total of 903 studies were identified; 41 were selected for qualitative analysis and 38 for quantitative analysis. Twenty eight studies were classified as presenting uncertain risk of bias, 11 as low risk and 3 as high risk of bias. The prevalence levels, ranked from highest to lowest and considering the tooth and patient units, respectively, were: caries lesions (0.252 - 95% CI 0.158-0.375; 0.512 - 95% CI 0.385-0.639); hypersensitivity (0.286 - 95% CI 0.190-0.407; 0.417 - 95% CI 0.197-0.674), post-eruptive fracture (0.125 - 95% CI 0.099-0.158; 0.257 - 95% CI 0.145-0.412); atypical restorations (0.048 - 95% CI 0.030-0.077; 0.167 - 95% CI 0.096 - 0.274); tooth extraction (0.012 - 95% CI 0.007-0.019; 0.090 - 95% CI 0.019 - 0.331). All meta-analyses resulted in heterogeneity greater than 85%, with the exception of the outcome "tooth extraction" according to the tooth unit (I2 = 57.83). This heterogeneity may be attributed to factors such as differences in the location where the study was realized, the socioeconomic conditions of the studied population, the asymmetric nature of MIH, and patient age.

CONCLUSION

The most common consequences of MIH are caries lesions, hypersensitivity, and post-eruptive breakdown. (PROSPERO:CRD42020201410).

Assessment of diagnostic accuracy and reliability of reveal fluorescence dental loupes in detecting molar incisor hypomineralization in children

BACKGROUND

Molar-Incisor Hypomineralization (MIH) poses challenges to accurate diagnosis, impacting children's oral health. Traditional methods exhibit limitations, necessitating innovative approaches. This study aimed to evaluate the reliability and diagnostic accuracy Reveal Fluorescence Dental Loupes (RFDLs) for the detection of MIH METHODS: This cross-sectional study, adhering to STRAD guidelines, involved 38 healthy children (age 7-9) with MIH. Ethical approval and informed consent were obtained. Microscope images and Reveal loupes were employed for examinations. Validity was assessed against microscope results, and inter- and intra-examiner reliability were measured using ICC and Kappa coefficients. Sensitivity, specificity, and overall accuracy were calculated, with an AUC-ROC analysis for discriminatory ability.

RESULTS

Intra-examiner reliability scores were excellent (Examiner 1: ICC 0.92, Examiner 2: ICC 0.94). Inter-examiner reliability (Kappa 0.92) indicated almost perfect agreement. Reveal demonstrated high sensitivity (82.61 %) and specificity (92.59 %), with an overall accuracy of 88.70 %. AUC-ROC analysis supported its robust discriminatory ability (AUC: 0.871).

CONCLUSIONS

Reveal Fluorescence Dental Loupes emerged as a promising diagnostic tool for accurate MIH detection, particularly in outreach settings. The study highlights the transformative impact of accessible and reliable diagnostic tools on pediatric oral health outcomes. While acknowledging limitations and the absence of a gold standard, the findings contribute to advancing MIH diagnostic capabilities. Further research in diverse populations is warranted for comprehensive validation.

Prevalence and clinical presentation of molar incisor hypomineralisation among a population of children in the community of Madrid

OBJECTIVE

The main objective of this study was to estimate the prevalence of molar incisor hypomineralisation (MIH), an alteration of tooth enamel with an estimated worldwide prevalence rate of 14%, among children using primary care services in the Community of Madrid, Spain.

MATERIALS AND METHODS

This was a descriptive, cross-sectional and multicentre study. After calibrating all researchers and following the diagnostic criteria of the European Academy of Paediatric Dentistry (EAPD), children aged between 8 and 16 years who were users of the dental services at 8 primary oral health units of the Madrid Health Service (SERMAS) were included. The children underwent a dental examination, and the parents were asked to complete a questionnaire.

RESULTS

The prevalence of MIH was 28.63% (CI: 24.61-32.65%). The age cohorts most affected by MIH were 8 years (21.4%) and 11 years (20.7%). The presence of MIH was greater among girls (85; 60.71%) than among boys (55; 39.28%). The mean number of affected teeth per patient was 4.46 ± 2.8. The most frequently affected molar was the upper right first molar (74.3%), and the upper left central incisor was the most affected incisor (37.85%). Opacities were the defects most frequently recorded (63.57%).

CONCLUSIONS

The prevalence of MIH in this study is the highest of all relevant studies conducted in Spain.

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.

Molar Incisor Hypomineralization in adolescents and adults and its association with facial profile and occlusion

OBJECTIVES

To date, there are no data available in the scientific literature about the diagnosis of Molar Incisor Hypomineralization (MIH) in adults. We aimed to assess the MIH prevalence and clinical characteristics in adolescents and adults and its association with facial profile and occlusion.

MATERIALS AND METHODS

In this cross-sectional study, permanent teeth were evaluated in 275 patients between the ages of 12 and 49 at a dental clinic, using intraoral photographs. A calibrated examiner classified enamel hypomineralization using the MIH index. Statistical analyses were performed using chi-square, Fisher's tests, and ordinal logistic regression.

RESULTS

MIH was observed in 12.73% of all patients. The most commonly affected teeth were permanent molars, while incisors, premolars, and canines were less affected. MIH usually appears as demarcated opacities, with less than one-third of the tooth affected. There was no association between severe defects and facial profile and occlusion, but rather with the higher age of the participants.

CONCLUSION

Enamel hypomineralization mainly affects the first and second permanent molars, but it could also be observed in the third molars, although it is not associated with the orthodontic characteristics investigated.

CLINICAL RELEVANCE

This is the first study to highlight the prevalence of MIH in adults. This result showed the importance of other specialists beyond Pediatric Dentistry in the diagnosis of this defect. In addition, hypomineralization of other permanent teeth (canines, premolars, and second molars) has been described previously in other studies, but this is the first to identify MIH in third molars.

Clinical evaluation of giomer- and resin-based fissure sealants on permanent molars affected by molar-incisor hypomineralization: a randomized clinical trial

BACKGROUND

Molar-incisor hypomineralization (MIH) is a common condition among children that significantly increases the risk of caries. The objective of this research was to evaluate the clinical success of giomer- and conventional resin-based sealants applied on first permanent molars (FPMs) affected by MIH.

METHODS

One-hundred FPMs with MIH which were indicated for non-invasive fissure sealant were selected in 39 children, aged 6-12 years. Using a split mouth design, the FPMs were randomized into two groups; Group 1. Resin sealant (etch-and-rinse + Conceal F) and Group 2. Giomer sealant (self-etch primer + BeautiSealant). Clinical evaluation was performed using the modified United States Public Health Service (USPHS) criteria at 1, 3, 6 and 12 months. The Log-rank, Fisher's exact test and Kaplan-Meier analysis were used for statistical analysis.

RESULTS

At 12 months, the retention rates in Group 1 and Group 2 were 68% and %8, respectively (p = 0.000). The cumulative survival rates of conventional resin sealants were significantly higher than giomer sealants for all follow-up visits (p < 0.05). In Groups 1 and 2, the distribution of unsuccessful sealants on mandibular vs maxillary FPMs were 32.1% vs 31.8% (p = 0.612) and 91.7% vs 92.3% (p = 0.664), respectively. Although the success rate was higher for teeth with white opacities or lesions with less extension in Group 1, no significant difference was found. The average survival time was found as 10.46 ± 3.21 months in Group 1 and 4.02 ± 4.43 months in Group 2.

CONCLUSIONS

The conventional resin-based sealants yielded a better clinical performance over the 12-month evaluation period than the giomer sealants which were applied with self-etch primer. The high failure rate observed in giomer sealants could be explained by the possible deficiency in the etching capacity of self-etch primer on MIH-affected teeth. Trial registration ClinicalTrials.gov, NCT04929782. Registered 10 June 2021-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT04929782 .

Virtual learning object for developing knowledge about the diagnosis and management of molar incisor hypomineralization

AIM

To develop, apply, and evaluate a virtual learning object (VLO) for teaching undergraduate dental students and paediatric dentists to diagnose and manage molar incisor hypomineralization (MIH).

DESIGN

This controlled educational intervention included 170 undergraduate dental students and 50 paediatric dentists. The student intervention group (VLOG) was trained by the VLO, the control group of students (CG) received a synchronous virtual class, and the group of paediatric dentists (PDG) was trained by the VLO. Pre-test and post-test data were analyzed with a mixed one-way and Tukey's post hoc ANOVA test (α = 0.05). The answers to the questionnaire were analyzed with the one-way ANOVA test and Tukey's post hoc test (α = 0.05).

RESULTS

The values obtained in the pre-test were significantly lower than those obtained in the post-test for all groups. The specialists showed a higher level of knowledge before and after the MIH training compared with the students (p < .001). Similarly, statistical differences were found in the level of knowledge, which increased after MIH training (p < .001). There were no differences between the CG and VLOG.

CONCLUSIONS

The level of knowledge increased in all groups after training regardless of the method used. VLOG works similar to traditional teaching approaches.

Molar incisor hypomineralization: A review and prevalence in Japan

Molar incisor hypomineralization (MIH) is defined as hypomineralization of systemic origin of one to four first permanent molars, and incisors are also frequently affected. This disorder is a serious concern in pediatric dentistry. Teeth affected by MIH have many dental problems, such as hypersensitivity, poor aesthetics, and rapid progression of dental caries. The prevalence of MIH ranges from 2.8% to 21% among studies with more than 1000 subjects in different countries and age groups. The etiology of MIH is unclear, but genetic and environmental factors have been proposed. This review describes the prevalence, etiology, and clinical management of MIH. A detailed description of MIH prevalence in Japan is also provided.

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.

Orthodontic treatment of children with class II division 1 with severe MIH involving first permanent molars extractions: A case report

BACKGROUND

Class II division 1 is the most common malocclusion in Europe. When the overjet is severe, the risk of trauma on anterior maxillary teeth as well as the risk of being bullied at school is increased. From this point of view, early treatment reduces the risk of dental fracture and increases patient self-esteem. In another hand, MIH is frequent with a prevalence of around 15% in children with country specificity, and molars in particular are difficult to treat endodontically with good long-term results when the MIH is severe. In many cases when the third molars are present, the extraction of the affected teeth followed by an orthodontic treatment remains the best solution but requires adequate orthodontic mechanics.

OBJECTIVE

The purpose of this article is to display one case of class II division1 with MIH treated by orthopaedic therapy and followed by molar extractions and fixed appliance.

Estimating molar-incisor-hypomineralization among 8-year-olds based on 15-year public oral health practice-based data

Background: A wide range in the prevalence of molar-incisor-hypomineralization (MIH) has been reported. Population-based studies are recommended. However, such studies are expensive and time-consuming.Objectives: To estimate the magnitude of MIH condition among 8-year-olds based on routine oral health examinations and to associate first permanent molar (FPM) affection with that of other permanent teeth over time.Materials and methods: This retrospective study, with cross-sectional and longitudinal components, was based on electronic oral health records; all 8-year-olds examined between 2002 and 2016 were included.Results: The average estimated prevalence of MIH was 8.3%; yearly range was 4.8-15.9%. The mean number of affected teeth was 1.4; 62% had one affected tooth. One-surface defects were the most frequent (66%). Asymmetric distribution of affected teeth was observed. In follow-up, 10.7%, 8.4%, and 11.2% had at least one affected permanent canine, premolar, or second permanent molar, respectively. The proportion of children with other MIH-affected permanent teeth was higher in the group with ≥2 MIH-affected teeth than in group with one affected FPM at the age of 8.Conclusions: The average prevalence of MIH was comparable to that reported elsewhere. The number of MIH-affected teeth at early mixed dentition predicts the affection of other permanent teeth over time, mainly that of permanent canines. Further screening of children with MIH is recommended to improve individually tailored early preventive and restorative dental care.

Molar-Incisor Hypomineralisation and Allergic March

Background

Molar-incisor hypomineralisation is a disturbance in dental development that involves first permanent molars as well as permanent incisors with a prevalence that ranges from 2.5% to 40%.

Aim

The objective of this study was to investigate the effect of atopic diseases on the development of molar-incisor hypomineralisation.

Material and methods

The study was based on the review of the medical records of a group of 102 children whose age was between eight and 12 years and 11 months and who had previously been diagnosed with MIH.

Results

An association (χ², p≤0.05) has been found between molar-incisor hypomineralisation in children's mouths and the existence of: atopic dermatitis (OR=2.504; 1.54-4.05 CI 95%), food allergies (OR=2.171; 1.03-4.56 CI 95%), allergic rhinitis (OR=0.17; 0.02-1.27 CI 95%), and asthmatic bronchitis/asthma (OR=1.707; 1.05-2.76 CI 95%). When analyzing the pathologies by location, we found that atopic dermatitis, food allergies, allergic rhinitis and asthma were more frequent in children who had (p≤0.05) #12, #11, #21, #22, #36, #31, #41 and #42 affected.

Conclusions

The association between molar-incisor hypomineralisation and the presence of atopic diseases in the first 36 months of life underlines the convenience of approaching this problem from a multidisciplinary perspective.

Microbiology of molar-incisor hypomineralization lesions. A pilot study

Objective: An insufficient mineralization (hypomineralization) in the teeth during the maturation stage of amelogenesis cause defects in 3–44% of children. Here, we describe for the first time the microbiota associated with these defects and compared it to healthy teeth within the same subjects.

Methods: Supragingival dental plaque was sampled from healthy and affected teeth from 25 children with molar–incisor hypomineralization (MIH). Total DNA was extracted and the 16S rRNA gene was sequenced by Illumina sequencing in order to describe the bacterial composition.

Results: We detected a higher bacterial diversity in MIH samples, suggesting better bacterial adhesion or higher number of niches in those surfaces. We found the genera Catonella, Fusobacterium, Campylobacter, Tannerella, Centipeda, Streptobacillus, Alloprevotella and Selenomonas associated with hypomineralized teeth, whereas Rothia and Lautropia were associated with healthy sites.

Conclusion: The higher protein content of MIH-affected teeth could favour colonization by proteolytic microorganisms. The over-representation of bacteria associated with endodontic infections and periodontal pathologies suggests that, in addition to promote caries development, MIH could increase the risk of other oral diseases.

Molar incisor hypomineralisation in Lebanon: prevalence and clinical characteristics

BACKGROUND

Molar incisor hypomineralisation (MIH) is a qualitative enamel developmental defect affecting 1-4 first permanent molars and sometimes the permanent incisors. MIH is extremely widespread around the world and presents a considerable clinical problem in paediatric dentistry. Although, little prevalence data exist for Middle East populations including the Lebanese one.

AIM

The objectives of this study were to investigate the prevalence of MIH in 7-9-year-old Lebanese children, with relevance to gender, jaw and side distribution, and to assess the clinical status, extent and severity of MIH lesions of the affected teeth.

DESIGN

Representative sample (n = 659) of 7-9-year-old Lebanese children attending private and public schools distributed throughout Lebanon was examined for MIH. Clinical status, extent and severity of MIH lesions on FPMs and permanent incisors were scored using the short-form grading method (MIH index) of Ghanim et al. (Eur Arch Paediatr Dent 16:235-246, 2015).

RESULTS

An overall MIH prevalence of 26.7% was reported with no significant predilection for girls over boys. 52.8% of the cases present with only molars and. 47.2% with both molars and incisors and did not present any significant difference between upper and lower jaws (P = 0.325). Left-side FPMs were more affected than the right ones (P = 0.0218). Central incisors were significantly more affected than the laterals in both jaws (P < 0.0001). Maxillary central incisors were significantly more affected than their mandibular counterparts (P < 0.0001). Most of the clinical status was demarcated opacities extended on less than the third of the tooth surface. The extent of lesions correlated significantly with the number of affected molars. Most of the affected teeth presented with mild defects and the degree of severity was not correlated with gender but significantly increased with age.

CONCLUSIONS

MIH is prevalent in Lebanon. Further studies are required to analyse the possible systemic and environmental etiologies among Lebanese children.

Molar Incisor Hypomineralization in Colombia: Prevalence, Severity and Associated Risk Factors

Aim: To determine prevalence, severity, and risk factors associated with Molar Incisor Hypomineralization (MIH) in schoolchildren between 6 and 15 years of age in Medellin, Colombia. Study design: We conducted a retrospective observational study including 1.075 children born and residing in Medellin, Colombia. A structured questionnaire addressing gestational period and first three years of child's life was administered to biological mothers. Two calibrated examiners established MIH diagnosis following the European Academy of Paediatric Dentistry criteria. Data were analyzed using descriptive statistics, bivariate analysis, and linear regression with a 5% significance. Results: Study population was predominantly male (70.7%), average age was 9.3±1.9 years. Prevalence of MIH was 11,2%. The majority of defects (85%) were mild. MIH was associated with alterations during last gestational trimester, type of childbirth and respiratory problems. Conclusion. MIH prevalence in schoolchildren between 6 and 15 years of age was 11.2%, being mild defects more frequently found. MIH was associated with different factors during pregnancy and the first three years of life.

Molar-Incisor Hypomineralization: Positive Correlation with Atopic Dermatitis and Food Allergies

AIM

Molar-incisor hypomineralization is a disturbance in dental development that involves first permanent molars as well as permanent incisors with a prevalence that ranges from 2.5% to 40%. The objective of this study was to investigate the etiology of molar-incisor hypomineralization among school children from two randomly selected towns in the province of Barcelona, Spain.

STUDY DESIGN

A cross-sectional study was conducted with 705 children ranging in age from six years-old to 14 years and 11 months-old. Full mouth examinations were carried out in accordance with the European Academy of Paediatric Dentistry criteria for the diagnosis of molar-incisor hypomineralization, from April to July 2016.

RESULTS

A total of 56 cases of molar-incisor hypomineralization were found in 22 (39.3%) boys and 34 (60.7%) girls. MIH was significantly more prevalent among those who had atopic dermatitis (OR=90.9; 33.4-247.1 CI 95%), food allergies (OR=104.2; 12.2-887.5 CI 95%), bronchitis/asthma (OR=5.3; 2.7-10.1 CI 95%), varicella (OR=96.3; 41.9-221.1 CI 95%), otitis media (OR=12.2; 6.3-23.5 CI 95%), pneumonia (OR=276.7; 35.1-2183.7 CI 95%), and febrile syndrome (OR=7.8; 4.1-14.8 CI 95%).

CONCLUSIONS

The present research reveals for the first time a statistically significant relationship between atopic dermatitis and food allergies with the presence of molar-incisor hypomineralization.

Investigation of Clinical Characteristics and Etiological Factors in Children with Molar Incisor Hypomineralization

Aim

The purpose of the present study was to evaluate the clinical defects and etiological factors potentially involved in the onset of MIH in a pediatric sample.

Methods

120 children, selected from the university dental clinic, were included: 60 children (25 boys and 35 girls; average age: 9.8 ± 1.8 years) with MIH formed the test group and 60 children (27 boys and 33 girls; average age: 10.1 ± 2 years) without MIH constituted the control group. Distribution and severity of MIH defects were evaluated, and a questionnaire was used to investigate the etiological variables; chi-square, univariate, and multivariate statistical tests were performed (significance level set at p < 0.05).

Results

A total of 186 molars and 98 incisors exhibited MIH defects: 55 molars and 75 incisors showed mild defects, 91 molars and 20 incisors had moderate lesions, and 40 molars and 3 incisors showed severe lesions. Univariate and multivariate statistical analysis showed a significant association (p < 0.05) between MIH and ear, nose, and throat (ENT) disorders and the antibiotics used during pregnancy (0.019).

Conclusions

Moderate defects were more frequent in the molars, while mild lesions were more frequent in the incisors. Antibiotics used during pregnancy and ENT may be directly involved in the etiology of MIH in children.

Glass hybrid restorations as an alternative for restoring hypomineralized molars in the ART model

Background

This study aimed to evaluate the survival rate of glass hybrid restorations placed under the atraumatic restorative treatment (ART) technique in first permanent molars affected by molar incisor hypomineralization (MIH).

Methods

Sixty teeth with severe MIH associated to carious dentin lesions without pulp involvement were included. Treatments were performed by one trained dentist using the ART approach and restored with a glass hybrid restorative system (Equia Forte, GC®) on school premises. Treatments were evaluated after 6 and 12 months by an independent examiner using the modified ART criterion. Data analysis involved descriptive statistics and actuarial success analysis.

Results

The sample comprised 24 (54.54%) girls and 20 (45.45%) boys with a mean age of 10.55 (±1.25) years. In regard to the number of surfaces involved in the restorations, 29 (48.3%) comprised one surface and 31 (51.7%) two or more surfaces. Considering cavity extent, 25 (41%) presented dentin cavitation without cusp weakness, 23 (37.7%) with large dentin cavitation with cusp weakness and 13 (21.3%) with large dentin cavitation with the breakdown of one or more cusps. Only 4 teeth required local anesthesia. A success rate of 98.3% after 6 and 12 months was observed, as only one restoration failed. The only failure occurred in a restoration involving three or more sur-faces presenting the breakdown of all cusps.

Conclusion

Restorations using a glass hybrid restorative system and performed in the field with the ART technique proved, after 12 months of evaluation, to be an effective approach to preserving first permanent molars affected by MIH.

Trial registration

REBEC-RBR-8drccq (17/06/15).

Electronic supplementary material

The online version of this article (10.1186/s12903-018-0528-0) contains supplementary material, which is available to authorized users.

First Permanent Molars and Permanent Incisors Teeth by Tooth Prevalence of Molar-Incisor-Hypomineralisation in a Group of Spanish Schoolchildren

Background

Molar-incisor-hypomineralisation (MIH) is a disturbance in dental development that commonly involves first permanent molars but permanent incisors may also be compromised. The prevalence of MIH in the literature varies between 2.5% and 40% of the world child population. Little information is gained on the prevalence of MIH among children in Spain.

Aim

The aim of this study was to investigate the prevalence of MIH among school children from Barcelona, Spain.

Material and methods

A cross-sectional study which included 705 children, aged 6 -14 years and 11 months was carried out. Full mouth examinations were performed using the European Academy of Paediatric Dentistry (EAPD) criteria for the diagnosis of MIH.

Results

A total of 56 cases of MIH were found, 22 (39.3%) boys and 34 (60.7%) girls. The prevalence was 7.94% (6.39% for boys and 9.41% for girls). MIH lesions were seen more often in girls than boys (χ² = 4.9, p= 0.023) the male/female ratio being 1:1.54. Upper teeth were more prevalent than lower teeth in both genders with an upper/lower ratio of 1.86/1 for boys and 1.68/1 for girls.

Conclusion

Considered either by gender or by teeth, upper teeth and girls were ahead in our sample.

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.