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

Is there a rise of prevalence for Molar Incisor Hypomineralization? A meta-analysis of published data

Since Molar Incisor Hypomineralization was first described as a pathologic entity, public perception often suggests a considerable rise in prevalence of the respective disease. Since there are still considerable doubts regarding the etiology and-accordingly-prevention of MIH and respective therapeutic approaches are difficult this question is of considerable clinical and public interest. Accordingly, a systematic literature search in accordance with the PRISMA guidelines for systematic reviews on Medline, Cochrane Database, EMBASE, LILACS, Web of Science, Google scholar, Scopus was performed to retrieve original articles reporting the prevalence of MIH as defined by the European Academy of Pediatric Dentistry (EAPD). From initially 2360 retrieved titles, 344 full texts were assessed for possible inclusion and finally 167 articles of mainly moderate to high quality and based on data of 46'613 individuals were included in the meta-analysis. All studies published before 2001 had to be excluded since it was not possible to align the findings with the EAPD classification. Studies varied considerably regarding cohort size (25 to 23'320, mean 1'235)) and age (5.6-19 y, mean 9.8 y). Over all studies, the weighted mean for the prevalence for MIH was 12.8% (95% CI 11.5%-14.1%) and no significant changes with respect to either publication year or birthyear were found. A sub-analysis of eleven studies reporting on the prevalence in different age groups, however, revealed strong evidence for an increasing prevalence between the years 1992 (3%) and 2013 (13%).Therefore, based on data from cross-sectional studies a possible rise in prevalence of MIH remains unclear. Future prospective large-scale studies under standardized examination conditions with an emphasis on examiner calibration are needed to gain better understanding in the evolution of the prevalence of MIH.

MIH and Dental Caries in Children: A Systematic Review and Meta-Analysis

(1) Background: Molar-incisor hypomineralization (MIH) is a clinical condition affecting permanent teeth in children, with a documented rising trend in the last two decades. The aim of the present study was to analyze and synthesize the available evidence on caries experience (dmft/DMFT) and MIH in children. (2) Methods: A systematic review and meta-analysis were conducted according to the PRISMA statement. (3) Results: 59 papers published between 2007 and 2022 were included in the qualitative synthesis and 18 in the meta-analysis. The total sample of subjects was 17,717 (mean: 896), of which 2378 (13.4%) had MIH (mean: 119), with a girl/boy ratio of 1:1. The mean age of the enrolled participants was 8.6 (age range 7-10 years). Meta-analysis showed that MIH has a positive correlation with both dmft (effect size of 0.67, 95% CI [0.15, 1.19]) and DMFT (effect size of 0.56, 95% CI [0.41, 0.72]); (4) Conclusions: Children with MIH should be diagnosed correctly and on time. Treatment and management options for moderate and severe forms of MIH should consider prognosis based on known risk factors, and secondary and tertiary prevention policies should also consider the multifactorial nature of caries etiology.

Effects of different remineralization agents on MIH defects: a randomized clinical study

OBJECTIVES

The aim of this study was to present a comparative evaluation of the long-term efficacy of fluoride varnish and pastes containing CPP-ACP and CPP-ACP with fluoride (CPP-ACFP) in the remineralization of creamy-white and yellow-brown defects in permanent first molars with MIH.

MATERIALS AND METHODS

The study included 120 teeth with yellow-brown or creamy-white defects in 67 children (37 girls, 30 boys) aged 6-9 years (mean, 7.2) who were newly diagnosed with MIH with no substance loss or caries or prior restorative treatment. The patients were randomly divided into the experiment groups; control (oral hygiene motivation only), fluoride varnish, and pastes containing CPP-ACP and CPP-ACPF, and followed up for 24 months. The evaluations were made based on the ICDAS criteria and the measurements which were performed using the laser fluorescence method (DIAGNOdent, KaVo, Biberach, Germany) in the follow-ups.

RESULTS

The research was completed with 49 patients (23 females, 26 males; mean age, 7.7) and 90 teeth. All remineralization agents increased remineralization rates in both creamy-white and yellow-brown colored defects without presenting any statistically significant difference at the end of the follow-up period (p > 0.05). However, the effects of fluoride varnishes were late to observe when compared to pastes containing CPP-ACP and CPP-ACPF.

CONCLUSIONS

Pastes containing calcium and phosphate may be recommended for the longer-term preservation of teeth with yellow-brown defects which showed a post-eruptive breakdown in a shorter time.

CLINICAL RELEVANCE

There is a lack of studies investigating MIH treatments in which lesion appearance was recorded. This study evaluated creamy-white and yellow-brown MIH defects separately and reported long-term results of different remineralization agents.

The prevalence of molar-incisor hypomineralization: a systematic review and meta-analysis

Molar-Incisor Hypomineralization (MIH) is a qualitative defect of enamel of unknown etiology, affecting one or more permanent molars and may include incisors. This condition is a clinical challenge and its prevalence is still uncertain given the recent increase in research. Thus, we aimed to comprehensively estimate the overall prevalence of MIH and associated characteristics. This systematic review is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). We searched articles using PubMed, MEDLINE, CENTRAL, Web of Science, SciELO, LILACS and TRIP databases, until July 2021. Heterogeneity and publication bias were computed via I2 test statistics and Egger's significance test, respectively. Random-effects meta-analysis of prevalence were processed. We used the Strength of Recommendation Taxonomy [SORT] to grading the strength of evidence. Overall, 116 observational studies were included, with one study with moderate methodological quality and the remaining of high methodological quality. Subgroup analysis confirmed an influence of not using the 2003 MIH case definition (p = 0.0066). The pooled prevalence of MIH was 13.5% (95% CI 12.0-15.1, I2 = 98.0%). Affected incisors were seen in 36.6% (95% CI 30.0-43.7, I2 = 92.5%) of the cases. Lastly, the prevalence of hypomineralization of the second primary molars was observed in 3.6% of the MIH cases (95% CI 1.9-6.8, I2 = 96.3%). America was the continent with highest prevalence (15.3, 95% CI 12.8-18.3, p < 0.001, I2 = 96.3%) and Asia had the lowest prevalence (10.7, 95% CI 8.5-13.5, p < 0.001, I2 = 98.7%), however no continental differences were found. Sample size and year of publication were slight contributing factors to the heterogeneity in the analysis. Overall, these results were classified with a SORT A recommendation.

Inheritance pattern of molar-incisor hypomineralization

The aim of this study was to investigate the segregation patterns of molar incisor hypomineralization (MIH) in families, given the evidence that its etiology is influenced by genetics. Clinically, MIH may be detected in parents and/or siblings of MIH-affected children. Our study included children with at least one first permanent molar affected by MIH (proband) and their first-degree relatives (parents and siblings). The participants were examined clinically to detect MIH, according to the European Academy of Paediatric Dentistry criteria (2003). A total of 101 nuclear families (391 individuals) were studied. Proband diagnosis was followed by MIH classification of the subject, his parents and siblings, as affected, unaffected, or unknown. Segregation analysis was performed using the multivariate logistic regression model of the Statistical Analysis for Genetic Epidemiology package, and segregation models (general transmission, environmental, major gene, dominant, codominant and recessive models). The Akaike information criterion (AIC) was used to evaluate the most parsimonious model. In all, 130 affected individuals, 165 unaffected individuals, and 96 unknown individuals were studied. Severe MIH was found in 50.7% of the cases. A segregation analysis performed for MIH revealed the following different models: environmental and dominance (p = 0.05), major gene (p = 0.04), codominant (p = 0.15) and recessive models (p = 0.03). According to the AIC values, the codominant model was the most parsimonious (AIC = 308.36). Our results suggest that the codominant model could be the most likely for inheriting MIH. This result strengthens the evidence that genetic factors, such as multifactorial complex defect, influence MIH.

Molar incisor hypomineralization, prevalence, pattern and distribution in Sudanese children

BACKGROUND

Molar incisor hypomineralization (MIH) has serious impact on oral health-related quality of life for a child, due to its effects on tooth structure, aesthetics and behavior of the child. The current study was designed to determine the prevalence, pattern and distribution of MIH in school children in Sudan.

METHODS

This was a descriptive cross-sectional study involving 568 children, aged 8-11 years from schools in Khartoum State. Following the collection of their socio-demographic data, the children were examined for hypomineralization on the 12 MIH-index teeth, the pattern and distribution of the MIH. The data collected was analyzed to obtain descriptive statistics. The results related to the socio-demography and other dental-related factors were tested using chi-square test and Spearman Rank Correlation, with the significant level set at p < 0.05.

RESULTS

The prevalence of MIH in the study population was 20.1%. The majority of the participants had both permanent first molars (PFMs) and permanent incisors affected (12.5%). However, in 7.6% of the cases only molars were affected. Even though more maxillary teeth were affected when compared to the mandibular teeth, there was no statistical significant difference between the occurrence of hypomineralization on mandibular and maxillary molars (p = 0.22). Maxillary incisors were significantly more affected by MIH when related to the mandibular ones (p = 0.00). Demarcated opacities were the commonest pattern of MIH defects (69.9%) in the experimental group.

CONCLUSION

The prevalence of MIH in Sudanese children was 20.1%. In both dental arches, the permanent molars and incisors were frequently affected, with the demarcated opacity type of MIH being the most common form of defect.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSION

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

Demarcated opacity in primary teeth increases the prevalence of molar incisor hypomineralization

This cross-sectional study aimed to assess the prevalence of molar incisor hypomineralization (MIH) and its relationship with the number of primary teeth with developmental defects of enamel (DDE). A representative population-based sample of 731 schoolchildren was randomly selected from the public school system in Curitiba, Brazil. Schoolchildren aged 8 years with fully erupted permanent first molars and incisors were eligible for the study. MIH and DDE were classified by four calibrated examiners (kappa > 0.75) according to EAPD criteria and to the FDI-modified DDE index. Clinical data were collected in a school environment. Socioeconomic information was collected through a self-administered semistructured questionnaire applied to the children's caregivers. Statistical analyses were carried out using Poisson multiple regression with robust variance (α = 0.05). MIH prevalence was 12.1% (95%CI: 10-15), and opacities were the most prevalent defect. Socioeconomic factors were not associated with MIH. Children with demarcated opacity in primary teeth presented a higher prevalence of MIH than those without DDE in primary teeth. In the multiple analysis, the increase of one primary tooth affected by demarcated opacity increased the prevalence of MIH by 33% (PR = 1.33, 95%CI: 1.15-1.53, p < 0.001). Asian children had a higher prevalence of MIH (PR = 2.91, 95%CI: 1.08-8.09 p = 0.035) than did Caucasian children.Conclusion: Based on these findings, the prevalence of MIH in Curitiba was 12.1%. Demarcated opacity in primary teeth could be considered a predictor of MIH.

Prevalence of molar-incisor hypomineralization in Milwaukee, Wisconsin, USA: a pilot study

Purpose: This pilot study investigated the prevalence of Molar-Incisor Hypomineralization (MIH) in third-grade school children in Milwaukee Wisconsin, USA. Methods: A convenience sample of third-grade school children in the Milwaukee Public School System (MPS) participated in the study. Calibrated examiners trained on the European Academy of Paediatric Dentistry (EAPD) MIH recommendations examined the children between December 1, 2014 and June 30, 2015. Children were examined at their schools using a flashlight and mirror after receiving consent from parents/caregivers and assent from each child. Findings were recorded onto a standardized form by one of five trained examiners. Summary statistics were calculated, and bivariate analysis were done to identify factors associated with MIH. Results: A total of 375 children (average age =8.66 years, range 7-12) were examined, 60% females and 41% Hispanics. Overall, 36 (9.6%) of the children demonstrated findings consistent with the diagnosis of MIH. Among the teeth with MIH defects, severe defects were higher in lower molars. There were no statistically significant differences between those with and without MIH by sex, race/ethnicity, and socioeconomic status in this study. Conclusion: The study revealed that 9.6% of the children examined were affected by MIH. Future studies should focus on statewide and/or nationwide surveys in the United States to ascertain the extent and severity of the condition.

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.

Developmental defects of the enamel and its impact on the oral health quality of life of children resident in Southwest Nigeria

BACKGROUND

Developmental defects of the enamel (DDE) increase the risk for diseases that impact negatively on the quality of life. The objective of this study was to compare the oral health quality of life of children with molar-incisor-hypomineralisation (MIH) and enamel hypoplasia; and assess if caries worsened the impact of these lesions on the quality of life.

METHODS

This study recruited 853 6 to 16-years-old school children. They filled the Child-OIDP questionnaire. The MIH, enamel hypoplasia, caries and oral hygiene status was assessed. Poisson regression was used to determine the impact of MIH and enamel hypoplasia on the oral health quality of life, after adjusting for the effect of sex, age, socioeconomic class, oral hygiene and caries status.

RESULTS

The prevalence of MIH and enamel hypoplasia was 2.9% and 7.6% respectively. There was no significant difference in the mean child-OIDP scores of children with or without MIH (p = 0.57), children with or without enamel hypoplasia (p = 0.48), and children with enamel hypoplasia with and without caries (p = 0.30). Children with enamel hypoplasia and caries had worse outcomes for speaking (p = 0.01). Children with middle (AOR: 2.74; 95% CI: 1.60-4.67; P < 0.01) and low (AOR: 1.75; 95% CI: 1.04-2.95; p = 0.03) socioeconomic status, and those with caries (AOR: 2.02; 95% CI: 1.26-3.22; p = 0.03) had their oral health quality of life negatively impacted.

CONCLUSION

MIH and enamel hypoplasia had no significant impact on the overall oral health quality of life of children resident in southwestern Nigeria. However, children with caries and those from middle and low socioeconomic classes had poorer oral health quality of life.

Time expended on managing molar incisor hypomineralization in a pediatric dental clinic in Nigeria

This study assessed the difference in the number of visits made to a dental care clinic and the time spent providing specific dental treatment for children with and without molar incisor hypomineralization (MIH). Children aged 8 to 16 years who presented at the Pediatric Dental Unit of the Obafemi Awolowo University Teaching Hospital Complex, in Ile-Ife, Nigeria, were eligible for the study. A comprehensive medical and dental history was taken, and each child was clinically examined, diagnosed, and treated according to a drawn-up plan. The time taken to establish a diagnosis and to provide specific treatments (scaling and polishing, restoration, pulpectomy, extraction, and placement of stainless steel crowns) and the number of visits made to complete the treatment plan were recorded for each child. Differences in the number of visits, time expended to make a diagnosis and to treat children with and without MIH were analyzed. The average time for diagnosis (p = 0.001) and the average time for placing amalgam restorations (p = 0.008) were significantly longer in children with MIH than in those without it. Children with MIH made more visits to the clinic (p < 0.001).There was no significant difference in the average time for scaling and polishing (p = 0.08), glass ionomer cement restorations (p = 0.99), composite restorations (p = 0.26), pulpectomy (p = 0.42), tooth extraction (p = 0.06), and placement of a stainless steel crown (p = 0.83) in children with and without MIH. In conclusion, children with MIH required more time for oral health care. Placing amalgam restorations took significantly longer than placing tooth bonding restorative materials in children with MIH than in those without it.

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.

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.

Screening Children for Caries: An Ethical Dilemma in Nigeria

Dental caries is the main oral health challenge for children in Nigeria. Concern about its negative impact makes screening for caries in children an attractive public health strategy. The ability to detect the preclinical phase of caries, the availability of screening tools with high accuracy, and the possibility of treatment before onset of clinical symptoms with significant cost and health benefits, makes it appropriate for screening. However in Nigeria, the poor availability of highly specific and sensitive screening tools, poor access to oral health care and concerns with pre-screening consent, raise the question of the appropriateness of conducting screening programmes for children. We argue that a number of structural challenges associated with poor uptake of oral health care services need to be addressed before screening for caries can be considered ethically appropriate. These include facilitating access of children to quality oral health care and a systematic national approach to oral health implementation. Failure to address challenges associated with dental service utilization by children in Nigeria increases the risk of screening programmes promoting inequitable access to oral health care services.

Prevalence and family structures related factors associated with crown trauma in school children resident in suburban Nigeria

BACKGROUND

Multiple risk factors have been identified for traumatic dental injuries, including crown fractures, in various age groups and various populations. The objective of this study was to determine the prevalence, risk factors and family related factors for crown trauma among 8 to 16 year-old children in a suburban population, Nigeria.

METHODS

This is a secondary analysis of a data of 2107 children collected through a school-based survey. Study participants were 8 to 16 year-old resident in suburban Nigeria. The independent variables for the study were age, sex, socioeconomic status, and birth rank, family size and parenting status (one parent, step parent, both parents, and guardians). Details were collected using an interviewer administered questionnaire. Intraoral examination was conducted to identify presence of crown fracture. The independent variables associated with and predictors of crown trauma were determinedusing chi-square and logistic regression analysis respectively.

RESULTS

Only 167 (7.9 %) of the 2107 study participants had crown trauma. The teeth level prevalence of crown trauma was 0.33 %. Children with middle socioeconomic status had reduced odds of having crown trauma when compared with children with low socioeconomic status (AOR 0.50; CI 0.32-0.80). The odds of having crown traumawas more than doubled in males when compared with females (AOR 2.41; CI 1.72-3.39) and almost doubled in children living with single parents when compared with children living with both parents (AOR 1.94; CI 1.29-3.05).

CONCLUSIONS

The prevalence of crown traumawas low in this study population. Being a female and having lowsocioeconomic status significantly reduced the risk factors for crown traumawhile living with single parents increased risk for crown trauma.

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.

Hypomineralised second primary molars: prevalence, pattern and associated co morbidities in 8- to 10-year-old children in Ile-Ife, Nigeria

Background

This study tries to determine the prevalence and co-morbidities associated with hypomineralised second primary molars (HSPM) in 8- to 10- year-old children in Ile-Ife, Nigeria; and the co-existence of HSPM and Molar Incisor Hypomineralisation (MIH) in the study population.

Methods

This was a cross sectional study involving 8- to 10- year-old children in schooling in suburban Nigeria. Information was collected on the child's age, sex and socioeconomic status. Intraoral examination was conducted to determine the presence of HSPM, MIH, caries and the oral hygiene status of study participants. The severity of HSPM was also determined. The prevalence of HSPM, the association between HSPM, sex and socioeconomic status of study participants, the difference in the prevalence of caries and poor oral hygiene in children with and without HSPM, and the prevalence of HSPM and MIH co-morbidity were determined.

Results

Twenty seven of the 469 children examined (5.8 %) had HSPM. The tooth prevalence of HSPM was 3.9 %. There was no significant sex (p = 0.06), age (p = 0.41), and socioeconomic status (p = 0.67) differences between children with HSPM and without HSPM. More children with HSPM had caries (p ≤ 0.001) and poor oral hygiene (p = 0.01). Children with HSPM have increased odds having dental caries (AOR: 6.34; CI: 2.78–14.46; p = <0.001) and reduced odds of having good oral hygiene (AOR: 0.32; CI: 0.13–0.78; p = 0.01) when compare with children without HSPM. Also 77.8 % of children with HSPM also had MIH.

Conclusion

The prevalence of HSPM in the study population is significantly high. The large number of children with HSPM and MIH also suggests that HSPM is a predisposing factor for MIH. The significantly higher proportion of children with HSPM who had caries and poor oral hygiene makes it imperative to institute screening programmes for HSPM/MIH in the study population.

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.

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.