Molar incisor hypomineralization: prevalence, severity and clinical consequences in Brazilian children

United Arab Emirates dentists' perceptions about the management of broken down first permanent molars and their enforced extraction in children: a questionnaire survey

PURPOSE

The broken down first permanent molar (BDFPM) is common in children. Enforced extractions of first permanent molars (EExFPMs) guidelines were published in the United Kingdom (UK) in 2014. We aimed to assess the knowledge and practice of dentists in the United Arab Emirates (UAE) of BDFPMs in children in light of the guidelines.

METHODS

A cross-sectional sample of UAE-based dentists treating children completed a self-administered questionnaire covering; knowledge and practice of the principle of EExFPMs; to whom dentists would refer in case of BDFPMs; knowledge of the ideal age for EExFPMs (8-10 years) and finally actual awareness of the EExFPMs guidelines. Chi-square tests (p < 0.05).

RESULTS

A total of 199 questionnaires were completed (total return rate was 66.33%). There was no agreement on how to deal with a scenario of BDFPMs. Over 85% majority believed in saving BDFPMs rather than extracting them but 89% would consult/refer to other specialists. Whilst 51% of the participants had never carried out EExFPMs in children, 69% were aware of the EExFPMs concept and 61% knew the ideal timing of a lower FPM extraction. More than 82% were unaware of the actual UK EExFPMs guidelines. Paediatric dentists would consider EExFPMs more than other groups (p = 0.007).

CONCLUSION

In the UAE dentist sample surveyed, there was a preference for preserving BDFPMs rather than extracting them in children, despite knowing when the ideal time for extraction was. Training background and specialty were influencing factors. There was a lack of awareness of the actual UK 2014 EExFPMs guidelines.

Factors associated with molar-incisor hypomineralisation in schoolchildren aged 8-10 years: a case-control study

BACKGROUND

The aetiology of molar-incisor hypomineralisation (MIH) is multifactorial and may involve genetic and environmental factors.

AIM

To verify the factors associated with MIH in schoolchildren from 8 to 10 years of age.

DESIGN

This is a case-control study with a sample consisting of children aged 8 to 10 years, paired by gender and school type, in a ratio of 1:3. The case group included 186 children with MIH and the control included 558 children without MIH. Data were collected through a semi-structured questionnaire and clinical examination. Chi-square, linear-by-linear, Mann-Whitney, and logistic regression tests were conducted. A value of P < 0.05 was considered significant.

RESULTS

The prevalence of mild MIH was 19.5%, moderate MIH 2.2% and severe MIH 3.2%. An association was observed between MIH with treatment need and a higher mean DMF-T and decayed and missing teeth (P < 0.05). According to the aetiological factors studied, mothers who presented a fever during pregnancy had a 2.54 times greater chance of having children with severe MIH than mothers who did not present a fever (P = 0.045).

CONCLUSION

The presence of fever during pregnancy and the need for treatment were associated with MIH.

Prevalence of molar incisor hypomineralization and regional differences throughout Japan

Background

Molar incisor hypomineralization (MIH) frequently occurs in children worldwide. However, MIH prevalence throughout Japan has not yet been investigated. The purpose of this study was to clarify MIH prevalence rates and to consider potential regional differences throughout Japan.

Methods

A total of 4496 children aged 7–9 years throughout Japan were evaluated in this study. MIH prevalence rates among children were evaluated in eight regions throughout Japan. A child’s residence was defined as the mother’s residence during pregnancy. The localization of demarcated opacities and enamel breakdown was recorded on a standard code form using a guided record chart. Logistic regression analysis was used to evaluate whether MIH prevalence rates differed among age groups, sex, and regions.

Results

The overall prevalence of MIH in Japan was 19.8%. The prevalence of MIH was 14.0% in the Hokkaido region, 11.7% in the Tohoku region, 18.5% in the Kanto Shin-Etsu region, 19.3% in the Tokai Hokuriku region, 22.3% in the Kinki region, 19.8% in the Chugoku region, 28.1% in the Shikoku region, and 25.3% in the Kyushu region. These regional differences were statistically significant. Moreover, MIH prevalence rates decreased with age. No significant sex differences in MIH prevalence rates were demonstrated.

Conclusions

To our knowledge, this is the first MIH study carried out in several regions throughout Japan. Regional differences existed in MIH prevalence rates; particularly, MIH occurred more frequently in children residing in southwestern areas than those in northeastern areas of Japan.

The Association between Molar-Incisor Hypomineralization and Dental Caries with Socioeconomic Status as an Explanatory Variable in a Group of Finnish Children

The aim of this study was to investigate if a developmental enamel defect known as Molar-Incisor Hypomineralization (MIH) is associated with dental caries. Socioeconomic status (SES) was examined as a confounding factor between caries and MIH. In this cross-sectional study, 636 children, aged 8 to 13 years, from three towns (two rural areas and one urban area) in Finland were examined for MIH in line with the criteria of the European Academy of Paediatric Dentistry. Caries status for permanent teeth was recorded as decayed, missing and filled teeth (DMFT). Caries experience (DMFT > 0) in the first permanent molars (FPMs) was set as an outcome. SES was determined using a questionnaire completed by parents. The prevalence of MIH was 18.1%. The mean DMFT in FPMs for children with MIH was higher than for their peers, 1.03 ± 1.25 vs. 0.32 ± 0.80 (p = 0.000, Mann-Whitney U test). In a multivariate analysis using the generalized linear mixed model where locality, SES, age and MIH were taken into account as caries risk indicators, MIH was the strongest risk indicator of caries in FPMs (Odds Ratio: 6.60, 95% Confidence Interval: 3.83–11.39, p = 0.000). According to the study results, children with MIH have a higher risk for dental caries than children without MIH.

Adhesion to Enamel of Teeth Affected by Molar Incisor Hypomineralization: Literature Review

Background/Aim: Molar incisor hypomineralization (MIH) is a qualitative defect of systemic origin, affecting permanent first molars and often permanent incisors. The treatment modalities can include, amongst others, fissure sealants for prevention of dental caries and composite restorations. Both require adhesion to tooth structure. The aim of this study was to review the literature on the adhesion to enamel affected by MIH.

Material and Methods: A search of PupMed/Medline, ResearchGate and Google Scholar was performed and limited between 2003, when the judgement criteria for MIH were set, and 2016. Thirty-three papers were considered relevant to the subject including five in vivo and six in vitro studies. Studies involving less than ten teeth were excluded.

Results: A four-year clinical trial showed that the application of a total-etch 2-step adhesive system prior to sealant placement is superior to the etch-seal technique. Despite the high success rate of composite restorations shown in three clinical longitudinal studies, there are conflicting results over self-etch being superior to total etch adhesive systems. Pretreating the enamel surface, prior to the adhesive system, with fluoride preventive solutions could reduce the mikroleakage under orthodontic brackets. Three in vitro studies provide inconsistent data about NaOCl pretreating potentials to improve adhesion of composite restorations. Resin infiltration, prior to resin restorations, could improve the microhardness of defected enamel, which may lead to increased bond strength, especially in combination with NaOCl pretreatment.

Conclusions: Adhesion to enamel affected by molar incisor hypomeralization is inferior compared to normal enamel. Sealants applied with the etch-bond-seal technique have greater retention than with the etch-seal technique. Further research is required to provide evidence of the effectiveness of the adhesive system and pretreatment to achieve optimal bonding to MIH.

Prevalence and etiology of molar-incisor hypomineralization (MIH) in the city of Istanbul

Background/purpose

Molar-Incisor-Hypomineralisation (MIH) is the term used to depict a condition in which one or more of the permanent molar teeth and usually no less than one incisor tooth is hypomineralised and the prevalence rates vary from 2.4 to 40.2%. The aim of this study was to assess the prevalence and the risk factors of MIH in children in Istanbul, Turkey.

Materials and methods

A total of 1511 (760 M, 751 F), 8- to 11-year-old children were examined who had their first permanent molar and incisors evaluated using the EAPD criteria for MIH. Hypomineralized molars and incisors were recorded based on developmental defects of enamel index. The potential aetiological factors were retrieved through personal interview and etiological questions were asked to the parents. Statistical analysis was performed with a chi-Square test.

Results

MIH was observed in 215 (14.2%; 102 male, 113 female) children. The sample (1511 children) comprised 71 (9.9%) 8 year-olds with MIH and 144 (18.2%) 11 year-olds with MIH. A significant difference was found between 8 (9.9%) and 11-year-old (18.2%) children with MIH (p ≤ 0.001). Complications during the mother's pregnancy, birth prematurity, average breast feeding period, diarrhea frequency, digestive system diseases, asthma, frequent high fever, ear infection, renal failure, rubeola, chickenpox and parotitis were found to be significantly associated with MIH (p < 0.001).

Conclusion

There are many events that can cause MIH which we cannot control or predict. Therefore, longitudinal studies with large sample size are needed so as to determine how various likely etiological factors described affect the etiological role.

Breakdown of demarcated opacities related to molar-incisor hypomineralization: a longitudinal study

OBJECTIVES

This prospective longitudinal study aimed to evaluate if the occurrence of post-eruptive breakdown of demarcated opacities in hypomineralized teeth is influenced by the color or location of the opacity.

MATERIALS AND METHODS

Patients diagnosed with molar-incisor hypomineralization (MIH) between 2012 and 2014 were eligible. Two calibrated examiners performed the initial and follow-up evaluations according to European Academy of Paediatric Dentistry (EAPD) criteria. Sixty-five patients were included. Fifty-eight (89.2%), with a mean age of 8.8 years (SD: 1.4), were reassessed after 1 year. Two hundred and nine of 1155 tooth surfaces were considered for the study: 86 with white opacity (OP-W), 91 with yellow opacity (OP-Y), and 32 with enamel breakdown (EB).

RESULTS

From the OP-W, OP-Y, and EB, 14, 27.5, and 46.9% worsened to breakdown exposing dentin, atypical restoration, or extraction (DB + RA or EXT), respectively. Yellow opacities tended to be more prone to breakdown than white opacities. The occurrence of EB, DB + AR, or EXT was not influenced by the location (p = 0.25).

CONCLUSIONS

The color of the opacity seems to play an important role on the occurrence of fracture and should be considered as a potential predictor.

CLINICAL RELEVANCE

Dentists should be aware that demarcated opacities related to MIH tend to fracture over time. Moreover, children with MIH should be seen at shorter intervals.

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.

Are hypomineralised lesions on second primary molars (HSPM) a predictive sign of molar incisor hypomineralisation (MIH)? A systematic review and a meta-analysis

OBJECTIVES

Molar Incisor Hypomineralisation (MIH) and Hypomineralised Second Primary Molars (HSPM) involve qualitative structural developmental anomalies of tooth enamel affecting the first permanent molars (and often incisors) and the second primary molars, respectively. A putative relationship between HSPM and MIH has been reported in the scientific literature. The aim was to determine whether children with HSPM are more likely to develop MIH.

SOURCE

A systematic search using PubMed/Medline, Embase and Cochrane Library electronic databases for publications from 2001 to August 2017 investigating the link between MIH and HSPM was undertaken.

STUDY SELECTION

Four reviewers selected the studies independently, extracted the data according to PRISMA statement, and assessed the bias risk with the Newcastle-Ottawa Scale (NOS) criteria.

RESULTS

From 645 potentially eligible studies, 14 were selected for full text analysis and 5 were included in the meta-analysis. Cross-sectional and cohort studies were reported and 4662 participants were included. The meta-analyses were performed with a random model calculated an OR total of 4.66 (95% CI 2.11-10.26; P < 0.001). The weighted mean of the co-occurrence of HSPM and MIH prevalence was 19.94%.

DISCUSSION

The high heterogeneity (I² = 88%) can be explained by the great variation present in number of participants and variable caries risk. Despite the limitations of the study, the presence of HSPM is predictive for MIH, with greater MIH prevalence in the presence of mild HSPM.

CLINICAL SIGNIFICANCE

Early detection and preventive intervention could reduce MIH complications.

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.

The prevalence of molar incisor hypomineralization: evidence from 70 studies

OBJECTIVE

A growing number of studies have investigated the prevalence of Molar Incisor Hypomineralization (MIH) around the world. The aim of this study was to systematically estimate the pooled prevalence of MIH.

METHODS

A comprehensive literature research was completed in English and Chinese databases. Random effect models were used to calculate the pooled prevalence. To address the heterogeneity, meta-regression, and sensitivity analyzes were conducted. Publication bias was estimated by trim and fill method.

RESULTS

Seventy eligible studies were included. The pooled prevalence of MIH was 14.2% globally. In subgroup analysis, South America (18.0%, 95% CI: 13.8-22.2) and Spain (21.1%, 95% CI: 17.7-24.6) had the highest prevalence. There was no significant difference between males (14.3%, 95% CI: 12.0-16.6) and females (14.4%, 95% CI: 12.8-15.9). The prevalence of MIH among children 10 years of age or younger (15.1%, 95% CI: 12.1-18.2) was much higher than the prevalence of MIH among older children (12.1%, 95% CI: 8.0-16.3). Sample size explained 15.7% heterogeneity.

CONCLUSION

MIH has a high incidence globally, especially among children <10 years old. It is, therefore, imperative to develop more appropriate dental healthcare strategies to care for these children and to identify the etiology of MIH to prevent it occurring.

Degree of severity of molar incisor hypomineralization and its relation to dental caries

Molar incisor hypomineralization is a developmental defect of dental enamel associated with rapid caries progression. In order to discover whether molar incisor hypomineralization predisposes to dental caries, a cross-sectional cohort study was conducted in a sample of 414 children aged between eight and nine years. It was found that 24.2% of the children presented molar incisor hypomineralization. Of these, 72% had a mild form and 28% a severe form. Caries prevalence was greater among the children with severe form (60.7%) than in those with mild form (43.1%) or no molar incisor hypomineralization (45.5%). The caries indices were higher in out molar incisor hypomineralization (1.18) or with mild form (1.08). The tooth-surface caries ratio was significantly higher in surfaces with severe hypomineralization than in those with no hypomineralization or mild hypomineralization. A linear regression model showed that cariogenic food intake and the presence of severe molar incisor hypomineralization were significantly associated with DMFS. Consequently, an association was found to exist between dental caries and the presence of surfaces affected by severe molar incisor hypomineralization, which should be considered a risk factor within the multifactorial etiology of caries.

Risk factors associated with new caries lesions in permanent first molars in children: a 5-year historical cohort follow-up study

OBJECTIVE

The objective of this study is to analyze the factors associated with the occurrence of caries in the permanent teeth (PT) and in the permanent first molar (PFM) 5 years after their eruption.

MATERIAL AND METHODS

Children born in 2005 and enrolled in a community dental program were included. The inclusion criteria were: age 10 years in 2015; the availability of clinical dental history (CDH) data from before eruption of the PT and a follow-up period of 5 years after eruption of the PT. A total of 206 children were enrolled. Risk factors evaluated were: caries experience in the mother, educational level of the mother, frequent drug use, systemic diseases, eating habits, brushing frequency, presence of molar incisor hypomineralization (MIH) in PT, and caries in deciduous teeth (DT). Associations between explanatory factors and the DMF-T (decayed, missing, filled teeth in PT) and DMFT-M (DMF in PFM) indexes, independently considering cavitated or cavitated and non-cavitated caries as outcomes, were evaluated by poisson regression with robust variance analysis.

RESULTS

In the multivariate analysis, a cariogenic diet, especially soft drinks, was associated to high DMF-T and DMFT-M scores when both cavitated and non-cavitated caries were considered. A brushing frequency < 1 a day was significantly associated to high DMF-T scores. The presence of df-t (decayed and filled temporary teeth) score > 0 and MIH conditioned high DMF-T or DMFT-M values, considering cavitated or cavitated and non-cavitated caries.

CONCLUSIONS

The intake of sweets and soft drinks, brushing frequency, caries in DT, and MIH in PT were the best predictors of caries in PT.

CLINICAL RELEVANCE

Control of risk factors in early childhood is important for preventing caries in PT.

Caries Experience in Children with and without Molar-Incisor Hypomineralisation: A Case-Control Study

Aim: The aim of this study was to compare the caries experience of children with and without molar-incisor hypomineralisation (MIH). Methods: A case-control study was designed in which 130 children aged between 7 and 13 years with MIH (cases) were matched with 130 children without the condition (controls) according to age, sex, and school. Dental caries and MIH were assessed using the Caries Assessment Spectrum and Treatment (CAST) and European Academy of Paediatric Dentistry (EAPD) criteria, respectively, by three examiners. CAST was converted into DMFT/dmft; the Kruskal-Wallis test was performed to analyse whether dmft/DMFT was influenced by the severity of MIH. Associations between MIH and dental caries were analysed at child and tooth levels: between and within subjects, respectively. To correlate MIH severity and the occurrence of dental caries, the Cochran-Armitage test was used. Results: The mean age of the children was 9.63 ± 1.29 years. The mean dmft for cases was 1.23 ± 1.99 and for controls 1.71 ± 2.22 (p > 0.05). For the DMFT, the mean scores for cases and controls were 0.45 ± 0.90 and 0.07 ± 0.25, respectively (p < 0.001). The between-subject analysis showed no difference in relation to enamel carious lesions; however, the prevalence of dentine carious lesions was significantly higher in children with MIH than in those without the condition. The same pattern was seen for the within-subject analysis. It was observed that the increase in MIH severity resulted in more teeth being affected by dentine carious lesions (p = 0.0003). Conclusion: Children with MIH presented a higher experience of caries in the permanent dentition than those without the condition. MIH was considered a risk factor for caries development.

A systematic review on the association between molar incisor hypomineralization and dental caries

BACKGROUND

Molar incisor hypomineralization (MIH) is a defect of enamel. The lower strength of the enamel can lead to fractures that predispose for plaque accumulation and caries.

AIM

This systematic review aimed to assess the association between MIH and caries.

DESIGN

Studies involving children of all ages, which reported results on MIH and caries in the permanent dentition, were considered eligible. A search was performed in PubMed and was limited to the period from January 2003 to November 2015, and to studies written in English. Reviews, meta-analyses, and case reports were excluded. The studies were evaluated by use of the Newcastle-Ottawa Quality Assessment Scale (NOS).

RESULTS

Seventeen publications were compiled in the review. Most publications reported that children with MIH have higher caries experience. One study did not observe a difference in DMF values among children affected or not by MIH. Three studies reported that children with MIH were 2.1 to 4.6 times more likely to have caries in the permanent dentition than children without MIH.

CONCLUSIONS

A significant association between MIH and caries was found. The results should, however, be interpreted cautiously due to the lack of high-quality studies. The present systematic review confirms the need for further well-designed studies.

Do We Really Know the Prevalence of MIH?

AIM

To analyze the existing variability on molar incisor hypomineralization prevalence in the literature; to distinguish the various molar incisor hypomineralization prevalence rates in different countries, areas, and regions of the world; and to know the valid diagnostic criteria used for the correct identification of molar incisor hypomineralization prevalence.

STUDY DESIGN

A literature review from Medline and Cochrane Library online databases was performed using five terms individually or in combination. Articles not reporting diagnostic criteria employed and articles not written English were excluded. The results were analyzed by country, region, year of study, sample size, range of age, and prevalence rate.

RESULTS

A total of 37 articles in English were selected from 1987 to 2014 and from those only 14 employed the EAPD's 2003 diagnostic criteria. The reported age range varied from 5.5 to 17 years; the most frequently range used was 7 to 9 years. A wide prevalence range from 2.8% to 44% was found and 82.61% of the articles reported calibrated examiners.

CONCLUSIONS

Comparison among the results of the studies is difficult due to the use of different indexes and diagnostic criteria, the analysis variability, selection methods, and different age groups. In reality, we are probably far from knowing the real MIH prevalence.

Molar incisor hypomineralization in HIV-infected children and adolescents

The objective was to determine the prevalence of molar incisor hypomineralization (MIH) among individuals between 7 and 15 years old infected or noninfected with human immunodeficiency virus (HIV). The study was conducted with 33 HIV-infected individuals (study group; SG) and 66 non-HIV-infected schoolchildren (control group; CG), paired by gender and age. Data collection was based on medical records (SG), a questionnaire for caregivers and oral examination for diagnosis of MIH (European Academy of Pediatric Dentistry criteria) and caries (DMFT index and ICDAS). Data were analyzed with Mann-Whitney, chi-square, and Fisher's exact tests and logistic regression. In SG, MIH (45.5%) and caries (87.9%) had higher prevalence. MIH was associated with use of protease inhibitors in SG (OR: 2.14; 95% CI: 1.21 to 3.77) and incubator need in CG (OR: 2.80; 95% CI: 1.71 to 9.10). HIV-infected patients had a higher prevalence of MIH and dental caries in the permanent dentition.

Impact of molar-incisor hypomineralization on oral health-related quality of life in schoolchildren

This study evaluated the impact of molar-incisor hypomineralization (MIH) on oral health-related quality of life (OHRQoL) according to the perceptions of schoolchildren and their parents/caregivers. This cross-sectional study consisted of a sample of 594 schoolchildren between 11 and 14 years of age and their parents/caregivers who answered the questionnaires CPQ11-14ISF:16 and P-CPQ, respectively. The main independent variable of this study was MIH of the schoolchildren. Experience of dental caries, malocclusion, and socioeconomic status were treated as confounding variables. Statistical analysis used descriptive analysis and Poisson regression with robust variance. The prevalence of MIH was 18.9%. The overall P-CPQ score ranged from 0 to 35 (average = 7.26 ± 6.84), and the overall CPQ11-14ISF:16 score ranged from 0 to 47 (average = 11.92 ± 7.98). Severe MIH was associated with a greater negative impact of the "functional limitation" domain (RR = 1.41; 95%CI = 1.01-1.97), according to parents'/caregivers' perceptions. Severe MIH was associated with a greater negative impact of the "oral symptom" domain (RR = 1.30; 95%CI = 1.06-1.60) and functional limitation domain (RR = 1.42; 95%CI = 1.08-1.86), according to the schoolchildren's perceptions. Schoolchildren with severe MIH had a greater negative impact on the oral symptom and functional limitation domains than those without MIH. According to parents'/caregivers' perceptions, schoolchildren with severe MIH had a greater negative impact on the functional limitation domain than those without MIH.

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.

Hypomineralized Second Primary Molars as Predictor of Molar Incisor Hypomineralization

Molar incisor hypomineralization (MIH) is a developmental defect of dental enamel that shares features with hypomineralized second primary molars (HSPM). Prior to permanent tooth eruption, second primary molars could have predictive value for permanent molar and incisor hypomineralization. To assess this possible relationship, a cross-sectional study was conducted in a sample of 414 children aged 8 and 9 years from the INMA cohort in Valencia (Spain). A calibrated examiner (linear-weighted Kappa 0.83) performed the intraoral examinations at the University of Valencia between November 2013 and 2014, applying the diagnostic criteria for MIH and HSPM adopted by the European Academy of Paediatric Dentistry. 100 children (24.2%) presented MIH and 60 (14.5%) presented HSPM. Co-occurrence of the two defects was observed in 11.1% of the children examined. The positive predictive value was 76.7% (63.9–86.6) and the negative predictive value 84.7% (80.6–88.3). The positive likelihood ratio (S/1-E) was 10.3 (5.9–17.9) and the negative likelihood ratio (1-S/E) 0.57 (0.47–0.68). The odds ratio was 18.2 (9.39–35.48). It was concluded that while the presence of HSPM can be considered a predictor of MIH, indicating the need for monitoring and control, the absence of this defect in primary dentition does not rule out the appearance of MIH.

Five-minute Apgar score ≤ 5 and Molar Incisor Hypomineralisation (MIH) - a case control study

BACKGROUND

The aetiology of molar incisor hypomineralisation (MIH) is unclear. The asymmetric distribution of MIH in the dentition may indicate that an insult of short duration that affects ameloblasts at a vulnerable stage could be a causative factor. Apgar ≤ 5 at 5 min may indicate asphyxia (hypoxic-ischemic insult) during birth. It was hypnotised that low Apgar score during birth may cause MIH. The present study aimed to examine a possible association between Apgar ≤ 5 at 5 min and the occurrence of MIH.

METHOD

Two study groups were selected for examination. The cases comprised 67 children aged 8-10 years born with Apgar score equal to or below 5 after 5 min. The control group comprised 157 age-matched healthy children. First permanent molars, second primary molars and all permanent incisors were examined in all children. Clinical examination was undertaken by two calibrated examiners and intraoral close-up photographs of the teeth were later evaluated by three calibrated and blinded clinicians. Demarcated opacities, post-eruptive breakdown, atypical restorations and extractions due to MIH, according to the criteria of the European Association of Paediatric Dentistry, were assessed.

RESULTS

The prevalence of MIH did not differ between the two groups. A chi-square test failed to confirm any statistically significant relationship between 5-min Apgar scores and MIH occurrence. In addition, there was no statistically significant relationship between the number of affected first permanent molars in cases and controls.

CONCLUSION

There was no association between Apgar ≤ 5 at 5 min and the occurrence of MIH.

Peripartum events and molar-incisor hypomineralisation (MIH) amongst young patients in southwest France

AIM

This was to investigate the association of peripartum events with the occurrence of MIH.

METHODS

This study, carried out between 2010 and 2011, was based on objective information noted in child health booklets on putative risk factors for MIH during the Peripartum period, aged between 6 to 28 years. The target population consisted of patients with MIH and a control group. Among the 849 patients examined by two calibrated paediatric dentists, 75 patients with MIH were recorded. These patients attended for consultation either at the teaching dental hospital of Bordeaux (France) or at a private dental practice (Bordeaux, France). Pearson's Chi-squared test was used and Odds ratios (OR) with 95 % test-based confidence intervals (CI) were calculated.

RESULTS

Correlations were observed between hypoxia during delivery and occurrence of MIH (OR = 6.1; CI = 1.7-21.85), and also between birth by caesarean section and MIH (OR = 2.9; CI = 1.2-6.9). There was no association between prematurity and MIH.

CONCLUSIONS

Peripartum events such as hypoxia during birth or delivery by caesarean section are suggested to be risk factors for the occurrence of MIH in this population.

Association between Molar Incisor Hypomineralization in Schoolchildren and Both Prenatal and Postnatal Factors: A Population-Based Study

BACKGROUND

Although studies throughout the world have investigated potential factors involved in the occurrence of molar incisor hypomineralization (MIH), the findings are varied and inconclusive.

OBJECTIVE

The aim of the present study was to evaluate the prevalence of MIH and identify associated prenatal, perinatal and postnatal factors among Brazilian schoolchildren aged 8 and 9 years.

METHODS

A cross-sectional study was conducted with a randomly selected population-based sample of 1181 schoolchildren. Information on demographic and socioeconomic characteristics as well as prenatal, perinatal and postnatal aspects was obtained through questionnaires. The clinical examination included the investigation of MIH based on the criteria of the European Academy of Paediatric Dentistry. Dental caries in the permanent dentition and developmental defects of enamel (DDE) on the primary second molars were also recorded. Data analysis involved descriptive statistics, bivariate tests and Poisson regression with robust variance.

RESULTS

The prevalence of MIH was 20.4%. MIH was more frequent among children with dental caries in the permanent dentition (PR: 2.67; 95% CI: 1.98-3.61), those with DDE on the primary second molars (PR: 2.54; 95% CI: 1.87-3.45) and those who experienced asthma/bronchitis in the first four years of life (PR: 1.93; 95% CI: 1.45-2.56).

CONCLUSIONS

The prevalence of MIH was high and was associated with dental caries, the presence of DDE on primary second molars and the experience of asthma/bronchitis in early life. These findings could be useful in the identification of children in need of shorter recall intervals to prevent the consequences of MIH, such as enamel breakdown dental caries.

Family-Based Genetic Association for Molar-Incisor Hypomineralization

Despite some evidence of genetic and environmental factors on molar-incisor hypomineralization (MIH), its aetiology remains unclear. This family-based genetic association study aimed more comprehensively to investigate the genetic carriage potentially involved in MIH development. DNA was obtained from buccal cells of 391 individuals who were birth family members of 101 Brazilian nuclear families. Sixty-three single nucleotide polymorphisms (SNPs) were investigated in 21 candidate genes related to amelogenesis using the TaqMan™ OpenArray™ Genotyping platform. All SNPs were genotyped in 165 birth family members unaffected by MIH, 96 with unknown MIH status and 130 affected individuals (50.7% with severe MIH). Association analysis was performed by the transmission/disequilibrium test (TDT), and statistical results were corrected using the false discovery rate. Significant results were obtained for SNPs rs7821494 (FAM83H gene, OR = 3.7; 95% CI = 1.75-7.78), rs34367704 (AMBN gene, OR = 2.7; 95% CI = 1.16-6.58), rs3789334 (BMP2 gene, OR = 2.9; 95% CI = 1.34-6.35), rs6099486 (BMP7 gene, OR = 2.2; 95% CI = 1.14-4.38), rs762642 (BMP4 gene, OR = 2.3; 95% CI = 1.38-3.65), rs7664896 (ENAM gene, OR = 2.1; 95% CI = 1.19-3.51), rs1711399 (MMP20 gene, OR = 0.4; 95% CI = 0.20-0.72), rs1711423 (MMP20 gene, OR = 2.1; 95% CI = 1.18-3.61), rs2278163 (DLX3 gene, OR = 2.8; 95% CI = 1.26-6.41), rs6996321 (FGFR1 gene, OR = 2.7; 95% CI = 1.20-5.88), and rs5979395 (AMELX gene, OR = 11.7; 95% CI = 1.63-84.74). Through this family-based association study, we concluded that variations in genes related to amelogenesis were associated with the susceptibility to develop MIH. This result is in agreement with the multifactorial idea of the MIH aetiology, but further studies are necessary to investigate more thoroughly the factors that could influence MIH.

Amoxicillin diminishes the thickness of the enamel matrix that is deposited during the secretory stage in rats

BACKGROUND

The use of amoxicillin during early childhood has been associated with molar incisor hypomineralization.

AIM

The objective of this study was to determine whether the use of amoxicillin interferes with enamel development, during secretion and early mineralization stages.

DESIGN

Fifteen pregnant rats were randomly assigned to three groups that received physiological solution (sham group), 100 mg/kg/day amoxicillin (A100G), and 500 mg/kg/day amoxicillin (A500G). After birth, the pups in each group received the same treatment until post-natal day 7 or 12. The upper first molars were analyzed histomorphometrical and immunostaining with amelogenin on day 7, and MMP-20 on day 12 was performed using a semiquantitative method (H-score).

RESULTS

At 7 days, several vacuolar structures were observed in the ameloblasts in the A100G and A500G groups. A significant reduction of the enamel thickness (P < 0.001) was found in amoxicillin-treated rats compared with the sham group. Significant differences were not observed in enamel thickness (P > 0.05) between the groups of 12-day-old rats. Moreover, significant differences were not observed in the number of amelogenin- and MMP-20-immunolabeled ameloblasts (P > 0.05) between groups.

CONCLUSION

The present results suggest that amoxicillin interferes with the initial stages of amelogenesis by causing structural changes in the ameloblasts and a reduction of the enamel matrix.

Prevalence of molar incisor hypomineralization in 7-9-year-old children of Bengaluru City, India

Background:

Molar incisor hypomineralization (MIH) is a developmental defect. The prevalence of MIH ranges widely from 2.4% to 40.2%.

Aim:

This study was under taken to determine the prevalence of MIH in 7–9-year-old children of Bengaluru City, India.

Materials and Methods:

A cross-sectional epidemiological study was conducted in a representative sample of 2500 school children aged 7–9 years of Bengaluru, India. Oral examination was carried out by a single trained calibrated examiner under natural daylight.

Results:

Twelve children (0.48%) were diagnosed with MIH. A total of 68 teeth were observed with MIH. All four first permanent molars were affected in 50% of children. In the molar group, mandibular molars (29.41%) were more frequently affected than maxillary molars (27.94%).

Conclusion:

The prevalence of MIH in 7–9-year-old children of Bengaluru was 0.48%, with no gender predilection.

The prevalence and pattern of deciduous molar hypomineralization and molar-incisor hypomineralization in children from a suburban population in Nigeria

Background

Molar Incisor Hypoplasia (MIH) and Deciduous Molar Hypoplasia (DMH) have significant impact on the quality of life of affected individuals. The objective of the study was to determine the prevalence, pattern and clinical presentation of MIH and DMH in children resident in Ile-Ife, Nigeria, and their association with sex and socioeconomic status of the children.

Methods

Information on age, sex and socioeconomic status was collected from 563 children aged 3 to 5 years and 8 to 10 years using a structured questionnaire through a household survey. Clinical examination was conducted to assess for the presence of DMH and MIH. The prevalence of DMH and MIH were determined. Tests of association between sex, socioeconomic status, prevalence, and pattern of presentation of both DMH and MIH were conducted using Pearson’s Chi-squared test Fisher’s exact test.

Result

Fifteen (4.6 %) of the 327 children aged 3 to 5 years and 23 (9.7 %) of the 237 children aged 8 to 10 years had DMH and MIH respectively. There were no significant association between DMH, sex (p = 0.49) and socioeconomic status (p = 0.32). There were also no significant association between MIH, sex (p = 0.31) and socioeconomic status (p = 0.41). MIH/DMH co-morbidity was observed in eight (34.8 %) of the 23 children with MIH. The mandible and maxilla were affected equally. Antimere was not observed.

Conclusion

The prevalence of DMH and the prevalence of MIH in the study population were high. DMH and MIH were not associated with sex and socioeconomic status. There was no specific pattern identified in the presentation of DMH and MIH. The prevalence of DMH/MIH co-morbidity is also high. Patients with DMH should be screened for MIH.

Longitudinal Evaluation of the Structural Integrity of Teeth Affected by Molar Incisor Hypomineralisation

The aim of this prospective cohort study was to evaluate the risk of posteruptive breakdown and the development of caries lesions in teeth with molar incisor hypomineralisation (MIH). A total of 367 permanent incisors and first molars, affected and not affected by MIH lesions, of 45 children with MIH from Araraquara, São Paulo, Brazil, were evaluated at intervals from 6 to 12 months by assessing the severity of MIH, the presence of tooth caries lesions and the treatment needed. During the study period, all patients received preventive care. The data were analysed using Fisher's exact test and actuarial method survival analysis. Significant associations were also found in teeth between the presence of MIH and a DMFT index >0 in all periods and also between the need for treatment and the presence of MIH. The teeth affected by MIH opacities were healthy in 99% of incisors and 93% of molars at the end of the 12-month period. Due to the high likelihood of maintaining the tooth structure in opacities, the complete or premature removal of the affected area is not justified.

A comparison of the presentation of molar incisor hypomineralisation in two communities with different fluoride exposure

AIM

To compare the clinical presentation of two cohorts of children diagnosed with molar incisor hypomineralisation (MIH) and living in areas of low and high background fluoridation.

METHODS

The study population comprised 12-year-old children participating in the 2008-2009 National Dental Epidemiological Programme in five regions in Northern England. Participating dentists were trained and calibrated in the use of the modified Developmental Defects of Enamel Index. Children were examined at school under direct vision with the aid of a dental mirror. First permanent molars and incisors were recorded for the presence and type of enamel defects greater than 2 mm. A diagnosis of MIH was ascribed to any child with a demarcated defect in any first permanent molar. Risk ratios for the occurrence of demarcated, diffuse and hypoplastic defects were generated for MIH children in the fluoridated and non-fluoridated area.

RESULTS

3,233 children were examined. The prevalence of MIH in the fluoridated community was 11 % and in the non-fluoridated community was 17.5 %. Incisors in children with MIH were at greater risk of having demarcated defects (risk ratio 4.0, 3.6-4.5) and diffuse defects (risk ratio 2.2, 2.0-2.5). Molars in children with MIH were at greater risk of diffuse defects (risk ratio 4.4, 3.8-5.0). The teeth of children with MIH living in the fluoridated area were at greater risk of demarcated defects for both incisors (risk ratio 1.6, 1.3-2.0) and molars (risk ratio 1.3, 1.2-1.5) relative to the teeth of MIH children living in the non-fluoridated area.

CONCLUSIONS

Children with MIH were at increased risk of both diffuse and demarcated defects in their incisors. Children with MIH living in the fluoridated area were at increased risk of diffuse and demarcated defects relative to MIH children living in the non-fluoridated area.

Standardised studies on Molar Incisor Hypomineralisation (MIH) and Hypomineralised Second Primary Molars (HSPM): a need

In November 2014, a review of literature concerning prevalence data of Molar Incisor Hypomineralisation (MIH) and Hypomineralised Second Primary Molars (HSPM) was performed. A search of PubMed online databases was conducted for relevant articles published until November 2014. The reference lists of all retrieved articles were hand-searched. Studies were included after assessing the eligibility of the full-text article. Out of 1078 manuscripts, a total of 157 English written publications were selected based on title and abstract. Of these 157, 60 were included in the study and allocated as 52 MIH and 5 HSPM, and 3 for both MIH and HSPM. These studies utilised the European Academy of Paediatric Dentistry judgment criteria, the modified index of developmental defects of enamel (mDDE) and self-devised criteria, and demonstrated a wide variation in the reported prevalence (MIH 2.9-44 %; HSPM 0-21.8 %). Most values mentioned were representative for specific areas. More studies were performed in cities compared with rural areas. A great variation was found in calibration methods, number of participants, number of examiners and research protocols between the studies. The majority of the prevalence studies also investigated possible aetiological factors. To compare MIH and HSPM prevalence and or aetiological data around the world, standardisation of such studies seems essential. Standardisation of the research protocol should include a clearly described sample of children (minimum number of 300 for prevalence and 1000 for aetiology studies) and use of the same calibration sets and methods whereas aetiological studies need to be prospective in nature. A standardised protocol for future MIH and HSPM prevalence and aetiology studies is recommended.

Severity of MIH findings at tooth surface level among German school children

AIM

This study was to investigate the distribution and clinical characteristics of teeth diagnosed with MIH at surface and defect type level in a cohort of German children.

METHODS

The study cohort included 242 children diagnosed with MIH which had been recorded during the compulsory dental school examinations of 20 German primary schools. The subjects had been enrolled by cluster sampling. All children attended the second to fourth grade (age 7-10 years, mean 8.1 ± 0.8). The children were examined by five calibrated examiners (kappa = 0.9) after tooth brushing. The recording comprised teeth, surfaces, type and severity of MIH defects and was conducted using a portable light, mirrors and cotton rolls. MIH was registered according to the EAPD criteria. Defects <1 mm were not recorded. Statistical analysis included descriptive statistics and Spearman's correlation.

RESULTS

Most affected teeth were first permanent molars (71.4 %) followed by the maxillary central incisors (15.6 %). The most common defects were demarcated opacities (82.2 %), while the remaining 17.8 % of the affected teeth exhibited severe enamel defects. The most frequently affected surface in molars was the occlusal surface (72.4 %); in incisors, it was the buccal surface (73.5 %). There were no atypical restorations in the affected incisors. Different types of MIH defects at various surfaces of the same tooth were common. The number of affected tooth surfaces was positively correlated with the severity of MIH at child (p < 0.001).

CONCLUSIONS

The study demonstrates severe enamel defects involving in almost one-fifth of all MIH teeth. The knowledge of the intra-oral distribution and severity of MIH findings at the enamel surface level is important for assessing the treatment needs.

Prevalence, pattern and severity of molar incisor hypomineralisation in 8- to 10-year-old school children in Ile-Ife, Nigeria

AIM

This study aimed to determine the prevalence, pattern and severity of MIH in school children resident in a suburban population in Nigeria.

METHODS

This was a cross-sectional study involving pupils aged 8-10 years resident in suburban Nigeria. Details of each pupil's socio-demographic variables were collected. Intra-oral examination was conducted to determine the presence of MIH, the affected tooth and the severity of the lesion. The association between the prevalence of MIH and socio-demographic variables of each child was determined. The predictors of MIH were also determined using a binomial regression analysis.

RESULT

Eighty-three of the 469 children examined (17.7 %) had MIH. There was no significant association between sex (p = 0.58), socio-economic status (p = 0.09), age (p = 0.26) and MIH. There was also no significant difference in the number of teeth affected by MIH in the maxilla and mandible, and on the right and left side of the face. The most commonly affected teeth were the left mandibular molars. The occlusal surfaces of the first molars were mostly affected by MIH and the severity of MIH on the teeth examined varied from mild (80.8 %), moderate (14.0 %) to severe (5.2 %).

CONCLUSION

The prevalence of MIH in this study population is consistent with previous reports. The non-association between sex and MIH prevalence, the varied severity of the lesion and association between MIH affectation of the first permanent molars and central incisors give more weight to the possible role of environmental factors in the aetiology of the lesion. The non-association between MIH and socio-economic status may serve as a distinctive feature of MIH and chronological enamel hypoplasia.

Background factors of molar-incisor hypomineralization in a group of Finnish children

OBJECTIVE

Molar-Incisor Hypomineralization (MIH) is a common developmental enamel defect characterized by demarcated opacities in permanent molars and incisors. Its etiology still remains unclear. The aim of this retrospective cohort study was to assess if the socioeconomic environment of the child is associated with MIH.

MATERIALS AND METHODS

The study was located in two rural towns and three urban cities in Finland. A total of 818 children, between 7-13 years old, were examined for MIH using the evaluation criteria in line with those of the European Academy of Paediatric Dentistry, but excluding opacities smaller than 2 mm in diameter. The mothers filled in a questionnaire which included questions related to the family's way of living (e.g. area of residency, farming, day care attendance) and socioeconomic status (family income, number of mother's school years, level of maternal education).

RESULTS

The prevalence of MIH in the study population was 17.1%. Family income, urban residency and day care attendance were associated with MIH in the univariate analysis. In the multivariate analysis using binary logistic regression, only urban residency during a child's first 2 years of life remained associated with MIH. The prevalence of MIH in urban areas was 21.3% and in rural areas 11.5% (OR = 2.18, CI = 1.35-3.53, p = 0.001).

CONCLUSIONS

The prevalence of MIH was related to urban residency and could not be explained by any other factor included in the study.

Esthetic dental anomalies as motive for bullying in schoolchildren

Facial esthetics, including oral esthetics, can severely affect children's quality-of-life, causing physical, social and psychological impairment. Children and adolescents with esthetic-related dental malformations are potential targets for bullies. This study was aimed to present and discuss patients who suffered from bullying at school and family environment due to esthetic-related teeth anomalies. Providing an adequate esthetic dental treatment is an important step in their rehabilitation when the lack of esthetic is the main source of bullying. After dental treatment, we noted significant improvement in self-esteem, self-confidence, socialization and academic performance of all patients and improvement in parental satisfaction regarding the appearance of their children. It is imperative that both family and school care providers be constantly alert about bullying in order to prevent or interrupt aggressive and discriminatory practices against children and adolescents. Clearly, dental anomalies may be a motive for bullying.

Molar incisor hypomineralization, prevalence, and etiology

Aim. To evaluate the prevalence and possible etiological factors associated with molar incisor hypomineralization (MIH) among a group of children in Jeddah, Saudi Arabia. Methods. A group of 8-12-year-old children were recruited (n = 267) from the Pediatric Dental Clinics at the Faculty of Dentistry, King Abdulaziz University. Children had at least one first permanent molar (FPM), erupted or partially erupted. Demographic information, children's medical history, and pregnancy-related data were obtained. The crowns of the FPM and permanent incisors were examined for demarcated opacities, posteruptive breakdown (PEB), atypical restorations, and extracted FPMs. Children were considered to have MIH if one or more FPM with or without involvement of incisors met the diagnostic criteria. Results. MIH showed a prevalence of 8.6%. Demarcated opacities were the most common form. Maxillary central incisors were more affected than mandibular (P = 0.01). The condition was more prevalent in children with history of illnesses during the first four years of life including tonsillitis (P = 0.001), adenoiditis (P = 0.001), asthma (P = 0.001), fever (P = 0.014), and antibiotics intake (P = 0.001). Conclusions. The prevalence of MIH is significantly associated with childhood illnesses during the first four years of life including asthma, adenoid infections, tonsillitis, fever, and antibiotics intake.

Related factors of dental caries and molar incisor hypomineralisation in a group of children with cystic fibrosis

AIM

To investigate dental caries and molar incisor hypomineralisation (MIH)-related factors such as treatment, diet, brushing and salivary factors in children with cystic fibrosis (CF) compared with healthy peers.

STUDY DESIGN

A cohort study was performed.

METHODS

This study was performed on 30 CF children comprising patients at the Faculty of Medicine and 30 control children recruited from the Dental School. Salivary factors, dental caries, MIH, daily diet, brushing habits were analysed. Statistical analysis was calculated by SPSS for Windows.

RESULTS

Decay missing filled teeth (DMF-T) score was 4.6 ± 4.0 in CF and 7.7 ± 2.7 in control (p = 0.001). 43% of CF children with MIH were found to use antibiotics, but no significant difference in the caries experience was found with antibiotic usage (p > 0.05). DMF-T of CF adolescents (23%) who use Tobramycin was 7 ± 3.5. DMF-T of CF children (20%) who take other antibiotics was 2.5 ± 3.5, but no statistical difference was found (p = 0.054). Saliva pH, salivary flow rate, and buffering capacity were not found statistically significant (p > 0.05).

STATISTICS

Percentage arithmetic mean value, standard deviation, independent sample t test, Fisher's exact test, Chi-square test and Mann-Whitney U test were used, while a p value of <0.05 was considered statistically significant.

CONCLUSIONS

Medication and diet could be considered as a risk factor for dental caries and factors such as salivary pH, good oral hygiene could play a protective role for oral health CF children. MIH frequency and lower caries experience seen in CF children could be due to salivary factors or pharmacological treatment they take. The multidisciplinary approach team would be advantageous in the management of children with CF and oral health should be under control during early years of life by paediatric dentists.

Epidemiologic study of molar-incisor hypomineralization in 8-year-old Spanish children

AIM

To find the prevalence of molar-incisor hypomineralization (MIH) in a random sample of Spanish children, and to investigate the gender influence, distribution of defects, the treatment need associated and the relation between this disorder and dental caries.

DESIGN

A cross-sectional study was carried out to determine MIH and caries prevalence in a randomly selected sample of 840 children from the 8-year-old population of the Valencia region of Spain. The examinations were carried out in the children's schools by one examiner who had previously been calibrated with the MIH diagnostic criteria of the European Academy of Paediatric Dentistry (EAPD).

RESULTS

The percentage of children with MIH was 21.8% (95% CI 19.1-24.7), with a mean 3.5 teeth affected (2.4 molars and 1.1 incisors) been the maxillary molars the most affected. No gender differences were found. Of those with MIH, 56.8% presented lesions in both molars and incisors Children with MIH needed significantly more urgent and non-urgent treatment than those without MIH (chi-squared test P-value < 0.005). Both caries indices were significantly higher (Student's t-test P-value < 0.05) in the children with MIH than in the healthy children: the DMFT scores were 0.513 and 0.237 and the DMFS scores 1.20 and 0.79, respectively.

CONCLUSIONS

Molar-incisor hypomineralization prevalence is high in the child population of this region and equally affects boys and girls. The condition increases significantly the need of treatment of affected children. A significant association with dental caries was observed.

Molar-incisor hypomineralisation: a prevalence study amongst primary schoolchildren of Shiraz, Iran

AIM

To investigate the prevalence of molar-incisor hypomineralisation (MIH) amongst primary schoolchildren of Shiraz, Iran, taking into account the possible influence of biographic and socio-demographic parameters.

STUDY DESIGN AND METHODS

A randomised cluster sample of 9- to 11-year-old children (N = 810) had their first permanent molars and incisors (index teeth) evaluated using the European Academy of Paediatric Dentistry criteria for MIH. The examinations were conducted at schools by a calibrated examiner. Prevalence of MIH was assessed based on biographic and socio-demographic parameters including area of residency, school type, father's level of education, weight-for-age and height-for-age.

RESULTS AND STATISTICS

Of the children examined, 164/810 (20.2%) had MIH and 53.7% of them presented with MIH lesions in all first molars. Mild defects represented by demarcated yellow brown opacities comprised 35.5% of the total MIH lesions. The prevalence of MIH was significantly greater in girls, children with healthy body weight and height, those whose fathers did not have a tertiary education and from families of low socio-economic status. Regression analyses indicated that none of the biographic and socio-demographic variables represented a significant risk factor in the occurrence of MIH except for body weight. Obesity was negatively correlated to MIH (OR = 0.45; 95% CI 0.25-0.82).

CONCLUSIONS

The prevalence of MIH in a group of Iranian children was 20.2%. Biographic and socio-demographic parameters appeared to have no significant correlation with MIH except body weight, which warrants further research.

Aetiology of molar-incisor hypomineralisation (MIH) in Brazilian children

AIM

To determine the potential aetiological factors related to molar-incisor hypomineralisation (MIH) in Brazilian children.

METHODS

A total of 1,151 children aged 7-12 years (mean 8.86 ± 1.28), born and living in the urban area of Araraquara, Brazil, were examined by two examiners evaluating the presence of MIH according to criteria suggested by the European Academy of Paediatric Dentistry (2003). Their mothers completed a structured questionnaire about medical history, from pregnancy to the first 3 years of the children's life. Descriptive analyses of data and odds ratios (OR) with 95 % test-based confidence intervals (CI) were estimated. Chi-square test was used to evaluate the differences between groups.

RESULTS

The prevalence of MIH in the children was 12.3 %. The interviewing response rate was 90.4 %. The prevalence of miscarriage history (25 vs. 15.4 %; OR = 1.21; 95 % CI 0.30-4.92) and occurrence of anaemia (23 vs. 12.4 %; OR = 2.07; 95 % CI 0.50-8.63) were higher in mothers from MIH group than those from non-MIH group. However, these associations were not statically significant. In the children's medical history, rhinitis, bronchitis (56.5 vs. 52.5 %; OR = 1.17; 95 % CI 0.82-1.68), and high fever (20.4 vs. 18.2 %; OR = 1.14; 0.73-1.76) were more prevalent in MIH group, but there were no significant differences between the groups (p > 0.05).

CONCLUSIONS

No possible aetiological factor investigated was associated with MIH. Prospective studies are needed to define the aetiological factors involved with MIH.

Dental caries experience and Molar-Incisor Hypomineralization

OBJECTIVE

This cross-sectional study assessed the prevalence and severity of the enamel defects, known as Molar-Incisor Hypomineralization (MIH) and its relationship to dental caries.

MATERIALS AND METHODS

A sample of 1157 schoolchildren (population based), aged 6-12 years, of the Araraquara city-Brazil, was evaluated according to the European Academy of Paediatric Dentistry (EAPD) criteria by two trained examiners. The dental impact caused by MIH was evaluated with the Decayed, Missing and Filled Teeth (DMFT) index (WHO). Data were analyzed using ANOVA and Chi-square tests (p < 0.05). The socioeconomic status was collected using a questionnaire answered by parents.

RESULTS

The prevalence of MIH was 12.3%. Mild impairment was the most frequent diagnosis. DMFT of children with MIH was 0.89 (± 1.18), which are higher than those of the unaffected group (0.43 ± 1.01). An association was found between dental caries only in the permanent dentition of children with MIH (p = 0.0001). Family income was considered low in 85% of the families of children with MIH in the public system, while in private school it was 18% (p < 0.05).

CONCLUSION

The prevalence of MIH in Araraquara was associated with greater caries experience in the permanent dentition.

Is there a positive relationship between molar incisor hypomineralisations and the presence of dental caries?

OBJECTIVE

This epidemiological study aimed to compare the caries experience in 10-year-olds with and without molar incisor hypomineralisation (MIH).

METHODS

About 693 children from an ongoing birth cohort study (GINIplus10) were examined for caries lesions to determine the DMF index. Furthermore, enamel hypomineralisation (EH) was scored on all permanent teeth/surfaces, according to the criteria of the European Academy of Paediatric Dentistry. Children with EH were categorised into those with a minimum of one EH in the permanent dentition (MIH/1), with EH on at least one-first permanent molar (MIH/1A), on at least one-first permanent molar and permanent incisor (MIH/1B), and on other permanent teeth (MIH/1C).

RESULTS

The mean caries experience was 0.4 (SD 0.9) DMFT. Existence of MIH/1, MIH/1A, MIH/1B, and MIH/1C was determined in 36.5%, 14.7%, 9.4%, and 21.8% of all children. The corresponding DMFT values were the following: no MIH: 0.3 (SD 0.8); MIH/1: 0.5 (SD 0.9); MIH/1A: 0.5 (SD 0.9); MIH/1B: 0.4 (SD 0.9); and MIH/1C: 0.4 (SD 0.9) DMFT. No significant differences were found between all groups.

CONCLUSIONS

There was no relationship between the presence of EH/MIH and caries in 10-year-olds. A ratio of one EH-associated defect to two caries lesions indicates that both conditions are prevalent and influence the oral health status of 10-year-old children from Munich, Germany.

An in vivo investigation of salivary properties, enamel hypomineralisation, and carious lesion severity in a group of Iraqi schoolchildren

BACKGROUND

Hypomineralised enamel is a prevalent, congenital defect vulnerable to deteriorate post-eruptively particularly in the presence of an unfavourable oral environment.

AIMS

To assess the influence of salivary characteristics on the clinical presentation of hypomineralisation lesions diagnosed in first permanent and second primary molars and to evaluate caries severity in relation to the defect's clinical presentation.

DESIGN

Recruitment consisted of 445 seven- to nine-year-old participants, of whom 152 were diagnosed as having molar hypomineralisation (MH); the remaining unaffected subjects (N = 293) were considered their controls for saliva analysis. Dental caries status was assessed in 300 subjects of saliva sub-sample, equally divided as MH-affected and non-affected children. The International Caries Detection and Assessment System was used for caries detection. Salivary flow rates, viscosity, pH, and buffering capacity were determined.

RESULTS

Molar hypomineralisation-affected children have significantly higher mean caries scores compared to the non-affected group. Dentinal carious lesions were ten times more frequent in teeth with post-eruptive breakdown (PEB) than with teeth with opacities only. Low salivary flow rates (LSFR), moderately viscous saliva, and low pH were significantly more common in the affected group. LSFR and moderate and highly acidic saliva were more likely associated with PEB.

CONCLUSION

Demarcated hypomineralised enamel is a dynamic defect highly influenced by individual characteristics of the oral environment.

Trends of oral health care and dental treatment needs in relation to molar incisor hypomineralisation defects: a study amongst a group of Iraqi schoolchildren

BACKGROUND

The dynamic properties of molar-incisor-hypomineralisation lesions (MIH) may impact negatively on personal daily oral care resulting in increased treatment needs.

AIMS

To describe and compare individual oral health care practices between MIH-affected and non-affected children, to evaluate and compare dental treatment needs between hypomineralised and non-hypomineralised first permanent molars, and to explore the role of reported fluoride exposure in the development of MIH.

STUDY DESIGN

A cluster sample of 7-9 year-old Iraqi schoolchildren (823 of 1000 eligible, response rate 82.3%) had their first permanent molars and incisors evaluated using the European Academy of Paediatric Dentistry evaluation criteria for MIH. Of these 153 were diagnosed with the defect and were referred to as MIH-affected children.

METHODS

Mothers of the participating children were asked to complete an oral health-questionnaire administered at schools. This included questions regarding child's history of dental visits, fluoride intake and the pattern of oral hygiene practices. Assessment of the dental treatment requirements for the first permanent molars was performed in a sample subset drawn from a larger data set of affected children (n=100) having their teeth assessed previously for dental caries status following the International Caries Detection and Assessment System. The sample subset consisted of 130 hypomineralised molars and 270 non-hypomineralised molars.

RESULTS

Of the total sample, approximately 71% of parents had taken their children to the dentist at some stage. For the total sample, tooth restoration or extraction was the most likely causes for seeking dental care at the first dental appointment (57.9%). Tap water was the main source of water consumed at home by the majority of children (77.8%). The prevalence of dental caries and tooth restorations was higher in hypomineralised affected molars (78.5%) than in the defect-free molars (33.7%).

STATISTICS

MIH-affected children reported significantly higher frequency of seeking dental care than their non-affected counterparts (82.4%, 68.2%; respectively). They were over three times (OR = 3.18) more likely to visit the dentist complaining of pain and were over six times (OR = 6.37) more likely to seek dental care due to tooth sensitivity than their non-affected peers. No significant differences were found between the study groups in terms of tooth brushing and toothpaste history with brushing frequency "once-a-day" was commonly reported in both groups (75.5%). Early exposure to fluoridated water appeared to have a protective effect for MIH (OR=0.38). Affected molars required more than twice the amount of restorative care than unaffected molars.

CONCLUSIONS

MIH did not seem to have an impact on the personal daily oral hygiene practices; however, MIH patients were commonly seeking dental consultation and needed care more often to improve their oral health.