Molar-incisor-hypomineralisation: a literature review

Association between genetic factors and molar-incisor hypomineralisation or hypomineralised second primary molar: A systematic review

OBJECTIVE

To determine the association between genetic factors and molar-incisor hypomineralisation (MIH) and/or hypomineralised second primary molars by means of a systematic review.

DESIGN

A search was performed in Medline-PubMed, Scopus, Embase and Web of Science databases; manual search and search in gray literature were also performed. Selection of articles was performed independently by two researchers. A third examiner was involved in cases of disagreement. Data extraction was performed using an Excel® spreadsheet and independent analysis was performed for each outcome.

RESULTS

Sixteen studies were included. There was an association between MIH and genetic variants related to amelogenesis, immune response, xenobiotic detoxification and other genes. Moreover, interactions between amelogenesis and immune response genes, and SNPs in the aquaporin gene and vitamin D receptors were associated with MIH. Greater agreement of MIH was found in pairs of monozygotic twins than dizygotic twins. The heritability of MIH was 20 %. Hypomineralised second primary molars was associated with SNPs in the hypoxia-related HIF-1 gene and methylation in genes related to amelogenesis.

CONCLUSION

With very low or low certainty of evidence, an association was observed between MIH and SNPs in genes associated with amelogenesis, immune response, xenobiotic detox and ion transport. Interactions between genes related to amelogenesis and immune response as well as aquaporin genes were associated to MIH. With very low certainty of evidence, hypomineralised second primary molars was associated to a hypoxia-related gene and to methylation in genes related to amelogenesis. Moreover, higher agreement of MIH in pairs of monozygotic twins than dizygotic twins was observed.

Electromyographic analysis of the stomatognathic system of children with Molar-incisor hypomineralization

INTRODUCTION

Molar-incisor hypomineralization (MIH) is a qualitative defect of dental enamel that affects one or more permanent first molars, with or without involvement of the incisor teeth. This condition leads to challenges to dental care and treatment planning.

AIM

Based on the hypothesis that children who have MIH possibly present alterations in postural and masticatory activities and considering the absence of studies investigating these parameters, the present study evaluated the functionality of the stomatognathic system considering the mentioned aspects.

MATERIALS

The comparison of individuals with (MIHG; n = 32) and without MIH (CG; n = 32) was evaluated by electromyographic activity of the masseter and temporal muscles (right and left), as well as evaluation of the masticatory cycles during habitual mastication.

RESULTS

MIHG showed muscle hyperactivity in postural and dynamic conditions compared to the CG; higher electromyographic values for MIHG when compared to CG in the following postural conditions: at rest for the right temporal (p = 0.00) and left temporal muscles (p = 0.03); in the protrusion to the right temporal muscle (p = 0.02); in the right laterality for the right masseter (p = 0.00) and left temporal muscles (p = 0.01); in the left laterality for the right masseter (p = 0.03) and left temporal (p = 0.04) muscles. In dynamic conditions with consistent food, significance was observed for the left temporal (p = 0.01); and with soft food for the right (p = 0.01) and left temporal muscles (p = 0.04).

CONCLUSIONS

Children with MIH seem to have impaired functionality of the stomatognathic system. Children with MIH have alterations in the stomatognathic system.

Knowledge and Perceptions of Molar Incisor Hypomineralisation among General Dental Practitioners, Paediatric Dentists, and Other Dental Specialists in Indonesia

Molar incisor hypomineralisation (MIH) is a qualitative, dental enamel hypomineralisation defect affecting one to four first permanent molars, characterised by the present of asymmetries demarcated opacities, and is prevalent worldwide. An early diagnosis of MIH is crucial, to prevent further complications including the development of dental caries, hypersensitivity, pulp inflammation, and pain. Therefore, a thorough understanding of MIH is of clinical importance. This cross-sectional study aimed to evaluate the knowledge and perception of MIH among general dental practitioners (GD), paediatric dentists (PD), and other dental specialists (DS) in Indonesia using a self-administered questionnaire. Chi-square tests and Kruskal−Wallis tests were employed to analyse the data. A total of 266 dental practitioners—112 GD, 84 PD, and 60 DS—were included in this study and completed the online questionnaire. There were significant differences in the overall knowledge scores between GD, PD, and DS (p < 0.001). Specifically, the different between the tested groups were observed in the knowledge of caries pattern related to MIH and the aetiology of MIH. The majority of PD (83.3%) can differentiate the MIH-related caries pattern from the classic caries pattern. Moreover, the confident level in diagnosing and treating MIH teeth were higher in PD compared to GD and DS (p = 0.000). The majority of dental practitioners in all groups agreed on the necessity to obtain continuing education on MIH including the aetiology, diagnosis, and its treatment to improve their knowledge and confidence in MIH clinical management.

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

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

Prevalence, Caries, Dental Anxiety and Quality of Life in Children with MIH in Brussels, Belgium

Molar incisor hypomineralisation (MIH) is a dental enamel pathology responsible for unfavorable functional and aesthetic implications. The objective of this study is to assess the prevalence, dental anxiety, and quality of life related to oral health in children with MIH. In 14 schools in Brussels, Belgium, 290 children aged 8 to 9.5 answered Children’s Fear Survey Schedule-Dental Subscale (CFSS-DS) and Child-Oral Impact on Daily Performance (C-OIDP) questionnaires to assess dental anxiety and quality of life related to oral health (OHRQoL). Oral examinations allowed us to detect MIH according to standardized criteria. The MIH prevalence was 18.6%. The Decayed, Missing and Filled Teeth index (DMFT index) of MIH patients was significantly higher than non-MIH patients (p < 0.001), mainly due to more restored teeth. There was no significant association between MIH and dental anxiety or OHRQoL. Caries in the deciduous dentition was significantly associated with impaired quality of life. The MIH prevalence in Brussels is comparable to other European countries. MIH had no significant impact on dental anxiety and OHRQoL in this sample. The dynamic nature of MIH lesions requires early diagnosis and management to limit the evolution of the severity of the lesions and their implications. It is possible that older age groups may present more symptoms, however, this would require a longitudinal study.

Prevalence, Pattern, and Severity of Molar Incisor Hypomineralization in 8-12-year-old Schoolchildren of Moradabad City

Aim and objective

Recently, molar incisor hypomineralization (MIH) has become more evident and one of the most common reasons for loss of teeth in children after dental caries. Being a country with a diverse ethnic population, the prevalence of MIH in different regions of India may differ. Hence, the present study was undertaken to determine the prevalence, pattern, and severity of MIH in 8-12-year-old Schoolchildren in Moradabad city.

Materials and methods

This study was conducted in various schools of Moradabad city to target a sample of 2,300 children aged between 8 and 12 years. The examination was done in their respective schools by a calibrated examiner in natural daylight using European Academy of Pediatric Dentistry diagnostic criteria for MIH 2015. The results, thus obtained, were statistically analyzed using Pearson's Chi-square test.

Results

A prevalence of 3.96% (91/2300) for MIH was reported without any gender predilection. Molar hypomineralization showed a prevalence of 1.3% (29/2300) whereas the prevalence for hypomineralization of second primary molars was 1.4% (22/1620). The most common type of defect was type 2 and most of the affected teeth were of grade I. Mandibular molars were more commonly affected compared to the maxillary molars.

Conclusions

A prevalence of 3.96% (91/2300) was observed for MIH. Frequent dental screening camps should be organized in schools at the community level for the enhancement of early diagnosis of MIH and designing appropriate management strategies.

How to cite this article

Khan A, Garg N, Mayall SS, et al. Prevalence, Pattern, and Severity of Molar Incisor Hypomineralization in 8-12-year-old Schoolchildren of Moradabad City. Int J Clin Pediatr Dent 2022;15(2):168-174.

An evaluation of remineralised MIH using CPP-ACP and fluoride varnish: An in-situ and in-vitro study

BACKGROUND

Molar incisor hypomineralization (MIH) affected teeth have enamel with altered mineral content like decreased calcium and phosphorus and increased carbon content leading to porous enamel and subsequent post-eruptive breakdown.

AIM

An in situ study was conducted to evaluate and compare the effects of a Casein Phosphopeptide-Amorphous Calcium Phosphate (CPP-ACP)-based cream and fluoride varnish on the remineralization of MIH affected teeth.

METHODS

Enamel slabs were prepared from MIH affected teeth that had been extracted for various reasons and inserted in appliances of 30 participants who were undergoing interceptive orthodontic therapy. They were randomly divided into two groups using block randomization technique: Group A-daily single application of CPP-ACP cream (n = 15); Group B-professional application of fluoride varnishes every 3 months (n = 15). After 6 months of regular wear of the appliance, the enamel slabs were placed under Field Emission Scanning Microscope (FESEM) and Energy-Dispersive Spectroscopy (EDS) for evaluation of ultra structure and mineral content, respectively.

RESULTS

A significant increase in calcium and phosphorus content, and a decrease in carbon content was observed within the 6 months period, suggesting remineralization in both the groups. On comparing the Ca:P and Ca:C ratios, a significant increase in the Ca:C ratio was evident in the two groups. No significant difference was seen in the Ca:P ratio in the CPP-ACP group at six months. The inter-group comparison did not reveal any significant difference between the two groups either at baseline or at 6 months post-intervention.

CONCLUSION

Remineralization can be achieved in MIH affected teeth with the use of remineralizing agents.

Sensitivity Treatments for Teeth with Molar Incisor Hypomineralization: Protocol for a Randomized Controlled Trial

Background

The sensitivity of teeth with molar incisor hypomineralization (MIH) can affect children’s quality of life and is a challenging problem for dentists. Remineralizing agents such as sodium fluoride varnish seem to reduce the sensitivity of teeth with MIH, but long-term clinical trials with large samples are still needed for more evidence about its effectiveness as a desensitizing agent before its clinical recommendation.

Objective

This randomized clinical trial aims to compare three treatment interventions for teeth with MIH and hypersensitivity.

Methods

A total of 60 children aged 6-10 years presenting with at least one first permanent molar with sensitivity and no loss of enamel will be randomly assigned to three groups: the control group (sodium fluoride varnish; Duraphat, Colgate); experimental group I (4% titanium tetrafluoride varnish); and experimental group II (a coating resin containing surface prereacted glass-ionomer filler; PRG Barrier Coat, Shofu). The sodium fluoride varnish and 4% titanium tetrafluoride varnish will be applied once per week for 4 consecutive weeks and the PRG Barrier Coat resin will be applied in the first session and the application will be simulated the following 3 weeks to guarantee the blinding of the study. The primary outcome will be sensitivity level measured at different moments (before each material application, immediately after application or simulation, and 1, 2, 4, and 6 months after the last application/simulation) by one examiner using the Wong-Baker FACES Pain Rating Scale, the Schiff Cold Air Sensitivity Scale, and the FLACC (Face, Legs, Activity, Cry, Consolability) scale. As secondary outcomes, parental satisfaction and child self-reported discomfort after the treatment will be measured with a questionnaire prepared by the researcher. The data will undergo statistical analysis and the significance level will be set at 5%.

Results

The project was funded in 2018, and enrollment was completed in November 2019. The recruitment of participants is currently underway and the first results are expected to be submitted for publication in 2022.

Conclusions

If found effective in reducing the patient’s sensitivity long term, these agents can be considered as a treatment choice, and the findings will contribute to the development of a treatment protocol for teeth with sensitivity due to MIH.

Trial Registration

Brazilian Registry of Clinical Trials Universal Trial Number U1111-1237-6720; https://tinyurl.com/mr4x82k9

International Registered Report Identifier (IRRID)

DERR1-10.2196/27843

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

Shear bond strength of resin modified glass ionomer cement following photodynamic therapy, Er,Cr:YSGG and chlorhexidine in hypoplastic primary teeth

PURPOSE

This study investigates the micro shear bond strength of resin-modified glass ionomer cement (RMGIC) bonded to hypoplastic teeth after the application of chlorhexidine (CHX), sodium hypochlorite (NaOCl), Er;Cr:YSGG and methylene blue mediated antimicrobial photodynamic therapy (APDT).

METHODS

A total sample of 60 erupted and extracted hypoplastic teeth collected from < 16 years children were subjected to different conditioning protocols including control group that involved bonding of hypoplastic teeth with RMGIC; CHX and NaOCl groups that included hypoplastic enamel being treated with 0.2% CHX and 2% NaOCl solution for 30 s followed by rinsing and drying for 5 s, MB-PDT group involved methylene blue photosensitizer and Er,Cr:YSGG group. All specimens were processed for microshear bond strength in a universal tester. The fractured surface was examined using a stereomicroscope at 40 × magnification and categorized under adhesive, cohesive and mixed.

RESULTS

The highest microshear bond strength was noted for the control group (∼29 MPa). Whereas the specimens conditioned by NaOCl showed the lowest microshear bond strength (∼17 MPa). Among the treatment groups, APDT showed the highest bond strength values (∼22 MPa) as compared to chemical disinfection protocols. However, Er, Cr:YSGG showed slightly lower microshear bond strength as compared to APDT. No significant difference was noted between CHX and NaOCl groups (p > 0.05). There was a statistically significant difference when all the groups were compared together (p < 0.05). Microscopic analysis revealed that specimens bonded after APDT showed the highest adhesive failures (70%). The highest cohesive failures were seen in NaOCl group (40%). The mixed type of failures was seen in the control groups with none appearing for chemical disinfection protocols.

CONCLUSIONS

This study concludes that APDT could be a potential therapeutic strategy for increasing the microshear bond strength of RMGIC to hypoplastic enamel.

Knowledge, experience and perception regarding molar incisor hypomineralisation (MIH) among dentists and dental hygienists in Oslo, Norway

Aim

The aim of this study is to gather baseline information on knowledge, perceptions, clinical experience and treatment options regarding MIH among dental care providers in Oslo, Norway, before a larger epidemiological study.

Methods

An electronic questionnaire was distributed to dentists (n = 88) and dental hygienists (n = 47) working in the Public Dental Service (PDS) in Oslo. The questionnaire consisted of five sections related to sociodemographic, clinical experience, perceptions, clinical management and preferences for further training. Descriptive statistics with chi-squared test was used, and level of statistical significance was set to 5%.

Results

Replies were obtained from 74.1% (n = 100) after two reminders. All respondents encountered MIH in their practice. The respondents’ perception of the prevalence of MIH in Oslo varied. The majority felt confident when diagnosing MIH (86%). The clinicians qualified in the last 10 years felt more confident than those who had qualified earlier (p = 0.016). Most were self-confident when treating these patients (68.3%), however, nearly all (88%) agreed that MIH was a clinical problem. The clinician’s treatment of MIH varied. Difficulties achieving adequate local anaesthetic (71.4%) and the child’s behavioural problems (84.1%) were treatment barriers for the dentists. Approximately two thirds (69%) would like further training, in particular on the aetiology (70%), diagnosis (57%) and treatment (77%) of the developmental disorder.

Conclusion

All clinicians were familiar with the diagnosis of MIH and experienced the condition to be a clinical problem. Continuing education on aetiology, diagnosis and treatment of MIH is requested by dental health personnel.

Molar incisor hypomineralization: A review and prevalence in Japan

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

Management of molar-incisor hypomineralisation by general dental practitioners - part two: treatment

Introduction Molar-incisor hypomineralisation (MIH) is a common occurrence in primary and secondary care settings. While severe cases may need specialist care, mild cases should be managed in primary care.Aims To assess how UK-based general dental practitioners (GDPs) plan treatment for children with MIH using two clinical vignettesDesign An electronic vignette survey was designed using clinical photographs and radiographs. Vignette one presented a child with mild MIH who was unhappy about the appearance of his teeth. Vignette two presented an anxious child with severe MIH, caries and sensitivity. Further questions relating to confidence in management of MIH and referral were included. Participants were UK-based GDPs who regularly treat children. The survey was distributed by email and across social media platforms. Data collection occurred between February and May 2019.Results Fifty-eight GDPs completed the survey. Around half of participants addressed the aesthetic concerns of the child in vignette one. The majority of participants demonstrated sound treatment planning in terms of preventive care and management of molars. More GDPs identified increased caries risk in vignette two.Conclusion These findings demonstrate most GDPs in this study were working as effective tier one and two providers when faced with management of children with MIH.

Management of molar-incisor hypomineralisation by general dental practitioners - part one: diagnosis

Introduction Molar-incisor hypomineralisation (MIH) affects one in six children in the UK. For the majority of patients who have mild MIH, this should be managed in primary care.Aims To assess UK-based general dental practitioners' (GDPs) ability to diagnose MIH when presented with multiple clinical vignettes.Design An electronic vignette survey was designed with use of clinical photographs - six cases had MIH and/or hypomineralised second primary molars (HSPMs) (seven possible diagnoses). Four control cases showing caries, fluorosis, amelogenesis imperfecta and dentinogenesis imperfecta were also included. Participants were UK-based GDPs. The survey was distributed by email and across social media platforms. Data collection occurred between February and May 2019.Results Seventy-six GDPs completed the survey; 68.4% (n = 52) of participants were female and 83% (n = 63) of participants graduated after the year 2000. The number of accurate diagnoses for each case were as follows - mild MIH (molars/incisors) 65.79%; mild MIH (molars only) 3.95%; HSPM and MIH (HSPM result) 0%; HSPM and MIH (MIH result) 50%; severe MIH (post-eruptive breakdown) 63.16%; severe MIH (caries) 31.58%; HSPM 3.95%.Conclusion GDPs are able to accurately diagnose MIH best when both incisors and molars are affected and caries is not present.

Demarcated Opacities as Predictors of Progression of the Molar Incisor Hypomineralisation: a Pilot Study

Objectives

Demarcated opacities (DO) on teeth affected by Molar Incisor Hypomineralisation (MIH) were observed to investigate if parameters of DO existence and the number of teeth affected could be used to predict the progression of disease.

Material and methods

In 2009, the MIH prevalence was 11.5% (n=51) among 446 subjects in Sarajevo, aged from 6 to 9 years. In subjects with MIH who gave consent for further participation (n=25), the teeth with DO were observed after a 12-month period.

Results

our sample included 29 permanent incisors and 14 first permanent molars with DO. The number of teeth with light opacities was significantly higher than the number of teeth with dark opacities. Opacities were more numerous on surfaces which were not exposed to masticatory pressure. The size of tooth surface affected by DO occurrence ranged from 1.33% to 56.56%. The number of affected teeth ranged from two to six. A strong positive correlation between MIH progression and dark colored opacities located on the occlusal/incisal surface of teeth was noted. Larger part of tooth surface was affected by hypomineralisation in the case of dark-colored opacities. The DO presence on incisors was more likely to be located on vestibular surfaces and on the first permanent molars on their occlusal surfaces.

Conclusions

The color of DO occurrence was the best predictor for MIH progression both independently and in combination with the number of affected teeth. Location of DO occurrence was a good independent predictor for MIH progression. It is important to collect information about color and location of DO presence.

Management of Molar Incisor Hypomineralisation (MIH): A 1-Year Retrospective Study in a Specialist Secondary Care Centre in the UK

(1) Background: Molar incisor hypomineralisation (MIH) is an enamel defect that affects an estimated 14.2% of children worldwide. Care takes place in primary and secondary care facilities. (2) Aim: To investigate how children with MIH are managed within a specialist centre in the north of England. (3) Method: A retrospective service evaluation within the paediatric dentistry department was registered with the clinical governance unit. Children who attended consultant-led new-patient clinics between 1 January and 31 December 2015 with a diagnosis of MIH were included. The data collected concerned the pre-referral treatment, the history and diagnoses and the treatments completed. (4) Results: Out of 397 records reviewed, 48 (12.1%) had MIH, where 81.3% and 18.8% of patients had severe and mild MIH, respectively. The majority of patients (n = 44 (91.7%)) were referred appropriately. Treatment was completed at the specialist centre for 44 (91.7%) patients. Twenty-five (52.1%) patients had an extraction of one or more first permanent molar teeth. Sixteen patients had the extractions at between 8 and 10 years old and 2 had the extractions later as part of an orthodontic plan. (5) Conclusion: Most children had severe MIH and were referred at an appropriate time to facilitate the consideration of loss of poor prognosis of first permanent molars (FPMs). Most children required specialist management of their MIH.

Use of asthma drugs and prevalence of molar incisor hypomineralization

BACKGROUND

Asthma and molar incisor hypomineralization (MIH) are common diseases among children and have been suspected to be associated with each other.

AIM

To examine the association between asthma or the use of asthma drugs and the prevalence of MIH.

DESIGN

In a population-based cross-sectional study, we recorded MIH in 9-year-old children in Aalborg Municipality, Denmark, born in the year 2000. We used a unique 10-digit civil personal number to link data on MIH to population-based medical register data. The exposure was inhaled asthma medication from birth date until date of dental examination. The outcome was the overall prevalence of MIH according to use of asthma medication. Odds ratios (OR) of having MIH were adjusted for gender, use of antibiotics and amoxicillin, maternal smoking, pre- and perinatal complication, and hospital admissions.

RESULTS

We examined 1837 children, of which 542 (29.5%) had one or more molar(s) with MIH. The adjusted odds ratio of having MIH was 0.95 (95% CI: 0.60-1.51) among children with prescriptions of inhaled asthma medication.

CONCLUSION

In this study, where the results have been adjusted for confounding, we found no association between use of inhaled asthma medication and the prevalence of MIH.

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

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

Prevalence of MIH in children aged 12 to 15 years in Beijing, China

OBJECTIVES

To investigate the prevalence of molar-incisor hypomineralization (MIH) in children aged 12 to 15 years in Beijing, China.

MATERIALS AND METHODS

A cross-sectional study was performed to recruit children aged 12 to 15 years old based on the method of multi-stage cluster random sampling during the Fourth National Oral Health Survey in Beijing, China, from September 2015 to March 2016. The first permanent molars (FPMs) and permanent incisors were examined for the presence of MIH by a single-calibrated examiner according to the European Academy of Paediatric Dentistry (EAPD) criteria.

RESULTS

Of the 6523 children recruited, 655 (10.0%) had MIH. The average number of affected MIH teeth in children was 2.68 ± 1.51. There was no gender-specific difference. With respect to the distribution of MIH in the mandible and maxilla, the most common condition was the simultaneous involvement of both the upper and lower FPMs. The severity of MIH was positively correlated with the number of affected teeth. The prevalence of MIH was lower in children who resided in the central districts and whose mothers had received higher education.

CONCLUSION

MIH was relatively prevalent among children aged 12 to 15 years old in Beijing, China.

CLINICAL RELEVANCE

This study is the first epidemiological survey on the prevalence of MIH in the pediatric population in North China. Some demographic and sociological factors were associated with the presence of MIH.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Success of endodontic management of compromised first permanent molars in children: A systematic review

BACKGROUND

Endodontic therapies may be required in the management of compromised first permanent molar teeth; their success in children, however, is unknown.

AIM

To determine the success of endodontic therapies used on first permanent molar teeth in children aged sixteen and under.

DESIGN

MEDLINE, Embase, Cochrane library, CENTRAL, Clinicaltrials.gov, and the ISRCTN registry as well as relevant paediatric, endodontic, and traumatology journal were searched using a detailed search strategy. References of included studies were hand-searched. A PICOS question was formulated: (P): children aged sixteen and under; (I): endodontic therapies (not pulp capping) on a first permanent molar tooth; (C): no treatment; (O): clinical success of endodontic therapy; and (S): all study types included. Bias was assessed using the Cochrane and Robins-I risk tools. Quality of evidence was assessed using the GRADE approach. Significant heterogeneity precluded meta-analysis.

RESULTS

4172 studies were retrieved and eleven were included in the narrative review. Partial and coronal pulpotomies have high success rates in the short term and long term. Limited evidence is available for conventional pulpectomy or regenerative techniques.

CONCLUSIONS

Partial and coronal pulpotomies are successful endodontic therapies for use in a compromised child's first permanent molar.

Second primary molar hypomineralisation and drugs used during pregnancy and infancy. A systematic review

OBJECTIVES

Hypomineralised second primary molars (HSPM) are due to idiopathic hypomineralisation that affects from 1- to 4-s primary molars, and its aetiology remains unclear. Our objective was to systematically review studies in which the investigators had studied the association between HSPM and drug use during pregnancy and the first year of life.

MATERIALS AND METHODS

A systematic search for publications until July 2018 was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. No restrictions were placed on year of publication. The PECO Question was as follows: P, children exposed to drugs during pregnancy and the first year of life; E, drugs to which mothers, during pregnancy and their offspring were exposed; C, control groups from studies with the same characteristics not exposed to drugs during pregnancy and the first year of life; and O, relationship between drug exposure during pregnancy and the first year of life and HSPM. Two reviewers extracted the data and assessed the risk of bias using the Newcastle-Ottawa Scale criteria.

RESULTS

We initially identified 986 articles, or which seven were selected for review: two case-control studies, one cross-sectional studies and four cohort studies. Four studies reported data on drug consumption during pregnancy and four investigated drug use during the first year of life and the occurrence of enamel defects in primary dentition.

CONCLUSIONS

There is no clear evidence that the use of drugs during pregnancy and during the first year of life is associated with HSPM. Further well-designed prospective studies are needed.

CLINICAL RELEVANCE

Determining the etiological factors related to the development of HSPM would help to establish preventive protocols in patients at potential risk. As HSPM is predictive of molar incisor hypomineralisation (MIH), the application of preventive protocols would avoid complications in both the primary and permanent dentition.

Management of compromised first permanent molars in children: Cross-Sectional analysis of attitudes of UK general dental practitioners and specialists in paediatric dentistry

BACKGROUND

It is unclear on how children with compromised first permanent molars (cFPMs) are currently managed in the UK by either general dental practitioners (GDP) or specialists in paediatric dentistry (SPD).

AIM

Explore the current attitudes to the management of compromised first permanent molars amongst UK general dental practitioners and specialists in paediatric dentistry.

DESIGN

Self-completed online questionnaire including three clinical vignettes of 7, 9, and 15 years old with cFPM. All registered SPDs (n = 236), as of May 2017, 500 randomly selected GDPs from England, selected from a national performers list, and 52 Scottish GDPs, part of Scottish dental practice research network, were invited to complete the questionnaire.

RESULTS

About 71.6% (n = 53) of SPDs agreed that children with cFPM should be referred to a paediatric specialist for treatment planning, whereas the reverse for GDPs is true, as 86.8% (n = 138) believe they have a responsibility to treat these teeth. Responses to clinical vignettes suggest a slight preference amongst GDPs to restore cFPM, including root canal treatment, whereas SPDs have a slight preference towards extraction.

CONCLUSION

Current pathways for cFPM, amongst UK general dental practitioners and specialists in paediatric dentistry, vary greatly between and within each professional group.

Microshear bond strength of different restorative materials to teeth with molar-incisor-hypomineralisation (MIH): a pilot study

AIM

To compare the microshear bond strength of resin based composite (RBC) and resin modified glass ionomer cement (RMGIC) restorations when bonded to teeth with molar incisor hypomineralisation (MIH).

METHODS

Eleven first permanent molars with MIH were included in this study. Teeth were sectioned mesio-distally producing a total of 22 surfaces for testing. Each specimen was placed inside a plastic ring with the flattened surface in contact with a glass slab. The plastic ring was filled with autopolymerising acrylic resin to imbed the specimen leaving the enamel surface exposed. Each surface was then bonded to 0.96 mm diameter RBC and light cured RMGIC following the manufacturers' instructions. Microshear bond testing was performed after 24 h storage in distilled water at 37 °C. A Bisco shear tester was used to apply shear stress of 1 mm/min until failure. Wilcoxon signed-rank paired-test was used for comparison of bond strength values.

RESULTS

Microshear bond strength of RBC (30.80 ± 8.19 MPa) was significantly higher than that of RMGIC (11.13 ± 6.91 MPa) when bonded to hypomineralised permanent first molars (p < 0.001).

CONCLUSION

The microshear bond strength of RBC is significantly higher than that of RMGIC when bonded to MIH affected teeth. Therefore, RBC can be recommended as the restoration of choice for teeth with MIH whenever the clinical scenario allows.

Prevalence of Hypersensitivity in Teeth Affected by Molar-Incisor Hypomineralization (MIH)

AIM

This study aimed to investigate the prevalence of hypersensitivity in molar-incisor hypomineralization (MIH)-affected molars through a census carried out in 8-year-old schoolchildren.

METHODS

Examinations were conducted by a calibrated examiner, using the Nyvad criteria for caries diagnosis and a new criterion for MIH assessment. For hypersensitivity assessment, all MIH-affected molars were included. Nonaffected molars from the same child were used as controls. Air blast reaction was measured using the Visual Analogue Scale (VAS) and the Schiff Cold Air Sensitivity Scale (SCASS) scale, while tactile hypersensitivity was scored using VAS only. Statistical analysis was performed using the Kruskal-Wallis test followed by Dunn's multiple comparisons test for quantitative data. χ2 was used for the comparison of categorical data.

RESULTS

In total, 631 children were assessed, of whom 102 had MIH-affected molars (16.1%). Of these, 51.7 and 8.7% presented enamel and dentin carious lesions, respectively. Regarding the number of teeth, 239 molars were MIH affected (59.8%), with 188 (78.7%) being classified as mild (opacities only), 20 (8.4%) as moderate (posteruptive enamel breakdown), and 31 (13%) as severe (posteruptive breakdown involving dentin/atypical restorations). Hypersensitivity was recorded in only one control molar, while the prevalence of hypersensitivity in MIH-affected molars was 34.7%, being of low intensity and more prevalent in moderate (55%) and severe cases (51.6 %) than in mild cases (29.8%, p = 0.008). An association between hypersensitivity and the presence of mild and moderate cases was observed. Although the same association was observed for severe cases, it was not considered a reliable information as 90% of the MIH-affected molars with posteruptive breakdown involving dentin were affected by carious lesions. It is known that dental caries is a confounding factor for the presence of hypersensitivity.

CONCLUSIONS

Hypersensitivity was significantly higher in MIH-affected molars than in nonaffected molars, being associated with MIH teeth presenting opacities and posteruptive enamel breakdown.

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.

Dentists' perception, knowledge, and clinical management of molar-incisor-hypomineralisation in Kuwait: a cross-sectional study

Background

Molar-incisor Hypomineralisation (MIH) is considered as a global dental problem. There is little knowledge of general dental practitioners (GDPs) and dental specialists (DSs) about this condition in different parts of the world, particularly in Gulf Cooperation Council (GCC) countries. Hence, this study has been carried out to assess the knowledge of GDPS and DSs in Kuwait about MIH condition, its clinical presentation and management. Findings would help national school oral health program (SOHP) to promote good oral healthcare.

Methods

A structured questionnaire was distributed to 310 attendees of the 18th Kuwait Dental Association Scientific Conference, Kuwait. Data concerning demographic variables, prevalence, diagnosis, severity, training demands and clinical management of MIH were collected.

Results

A response rate of 71.3% (221/310) was reported. 94% of respondents noticed MIH in their practice. Yellow/brown demarcation has been observed as a common clinical presentation (> 50%). Almost 10–20% of MIH prevalence has been reported by the participants. Resin composite was the dental material often used in treating MIH teeth (~ 65%), and fewer than half would use it for treating moderately affected molars. Most respondents would use preformed metal crowns for severe MIH (63%). Dental journals were the information source for DSs; whereas, the internet was the information source for GDPs. Child’s behaviour was the main reported barrier for treatment of MIH affected children. Many GDPs felt unconfident when diagnosing MIH compared to dental specialists. Respondents supported the need to investigate MIH prevalence and to receive a clinical training.

Conclusions

Molar incisor hypomineralisation is a recognised dental condition by practitioners in Kuwait. Yellow/brown demarcated opacities were the most reported clinical presentation, and the composite resin was the most preferred dental material for restoring MIH teeth. Most GDPs and dental specialists would use preformed metal crowns for severely affected molars. GDPs reported low levels of confidence in MIH diagnosis which necessitates conducting continuing education courses to provide high- quality dental care for children with MIH.

Molar incisor hypomineralisation

Data sourcesThe Medline and Embase databases and hand searches in the journals International Journal of Paediatric Dentistry and European Archives of Paediatric Dentistry.Study selectionEnglish language cohort and case-control studies.Data extraction and synthesisStudy selection was carried out independently by two reviewers with data abstraction being conducted by a single reviewer and checked by a second reviewer. Risk of bias was assessed using a modified version of the Newcastle-Ottawa Scale (NOS). Adjusted (aOR) and unadjusted odds ratios (uOR), P-values and 95% confidence intervals (CI) were obtained from the studies. Meta-analysis was not conducted.ResultsTwenty-eight studies were included; 25 reported on MIH, three on hypomineralised second primary molars (HSPM). Nineteen of the studies were of cohort design (six prospective,13 retrospective) and nine were case controls. There was little evidence of an association between the most frequently investigated prenatal factors (smoking, maternal illness, maternal medication, maternal stress) and MIH. Similarly there was little evidence of an association between MIH and perinatal factors such as prematurity, low birth weight, caesarean delivery and birth complications. Early childhood illness, up to three or four years of age, was widely investigated, with six studies reporting a crude association. Associations between antibiotics, anti-asthma medication and breastfeeding were also evaluated. Only three studies looked at HSPM; one study suggested that maternal antibiotic use during pregnancy is unlikely to be associated with HSPM but maternal alcohol intake may be. Another study reported possible associations with a large number of factors, with perinatal factors and neonatal illness being most common, followed by prenatal factors.ConclusionsPrenatal and perinatal factors are infrequently associated with MIH. However, despite a lack of prospective studies, early childhood illness (in particular fever) appears to be associated with MIH. Further prospective studies that adjust for confounding based on biological principles, as well as genetic and epigenetic studies, are needed because the aetiology is likely to be multifactorial.

Bonding strategies for MIH-affected enamel and dentin

OBJECTIVES

Aim of the present study was to evaluate resin composite adhesion to dental hard tissues affected by molar incisor hypomineralisation (MIH).

METHODS

94 freshly extracted human molars and incisors (53 suffering MIH) were used. 68 teeth (35 with MIH) were used for μ-TBS tests in enamel and dentin, 26 (18 with MIH) for qualitative evaluation. Specimens were bonded with Clearfil SE Bond, Scotchbond Universal, and OptiBond FL. For MIH affected enamel, additional OptiBond FL groups with NaOCl and NaOCl+Icon were investigated. Beside fractographic analysis, also qualitative evaluations were performed using SEM at different magnifications as well as histological sectioning.

RESULTS

Highest μ-TBS values were recorded with dentin specimens (ANOVA, mod. LSD, p<0.05). Results were independent of adhesive and dentin substrate (p>0.05). Pre-test failures did not occur in dentin specimens. Sound enamel specimens exhibited significantly higher μ-TBS values than MIH enamel (p<0.05). The two-step self-etch adhesive (Clearfil SE Bond) and the two-step etch-and-rinse adhesive (Scotchbond Universal) showed the lowest values in affected enamel specimens (p<0.05) with most pre-test failures (p<0.05). OptiBond FL on affected enamel showed better results than Clearfil SE Bond (p<0.05). An additional pre-treatment of affected enamel with NaOCl or NaOCl and Icon did not enhance enamel bonding (p>0.05), however, it caused less pre-test failures (p<0.05). Micromorphological analyses revealed that conventional phosphoric acid etching produces a much less pronounced etching pattern in affected enamel and a porous structure as weak link for the resin-enamel bond was identified.

SIGNIFICANCE

Bonding to porous hypomineralized MIH enamel is the limiting factor in adhesion to MIH teeth. MIH-affected dentin may be bonded conventionally.

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.

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.

Efficacy of desensitizing products containing 8% arginine and calcium carbonate for hypersensitivity relief in MIH-affected molars: an 8-week clinical study

Objectives

The objective of this study was to compare the efficacy in reducing hypersensitivity in molar incisor hypomineralization (MIH)-affected molars immediately and over 8 weeks combining a single in-office application and a homed-based program with desensitizing products containing 8% arginine and calcium carbonate.

Materials and methods

Nineteen children with at least one MIH-affected molar with hypersensitivity were included. Hypersensitivity was assessed with an evaporative (air) stimulus and a tactile stimulus. Each child received a single in-office treatment with a desensitizing paste containing 8% arginine and calcium carbonate (elmex Sensitive Professional desensitizing paste), followed by 8 weeks of brushing twice daily with a desensitizing toothpaste containing 8% arginine, calcium carbonate with 1450 ppm fluoride (elmex Sensitive Professional toothpaste), using the elmex Sensitive Professional toothbrush. Additionally, the corresponding mouthwash (elmex Sensitive Professional mouthwash) was used. Clinical assessments were made at baseline, immediately after the in-office treatment and after 1, 2, 4 and 8 weeks of brushing twice daily.

Results

Fifty-six molars with an air blast hypersensitivity score of 2 or 3 (Schiff Cold Air Sensitivity Scale) were included. Application of the desensitizing paste decreased hypersensitivity significantly immediately and throughout the 8 weeks recalls (p < 0.001).

Conclusions

In conclusion, 8% arginine and calcium carbonate were able to reduce hypersensitivity successfully during this 8-week trial.

Clinical relevance

Hypersensitivity is a major complaint in patients with MIH. This is the first study evaluating the desensitizing effect of a desensitizing paste containing 8% arginine and calcium carbonate in patients with 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.

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.

DENTAL STATUS OF CHILDREN WITH THE TEETH FORMATION DISORDERS

Aim of research: to analyze the dental status of children with the teeth formation disorders on the background of the digestive diseases (DD). Object of research – the change of the teeth hard tissues and periodontal tissues, subject of research – clinical characteristics of the status of teeth hard tissues and periodontal ones. Results of research: in children with chronological enamel hypoplasia (CEH) and molar-incisor hypomineralization (MIH) on the background of digestive diseases (Class ICD-10, К00-К93: “Gastritis and duodenitis” (К29), “Cholecystitis” (К81), “Other bile-excreting diseases” (К83)) was fixed the high and very high intensity of the dental caries, respectively. Caries as CEH and MIH complication was diagnosed in 55,81 % and 42,85 % of examined, respectively. In children with CEH and MIH on the background of digestive organ diseases was diagnosed the middle severity of gingivitis РМА, Papillary, Marginal, Alveolar Indices): 29,13±8,87 % and 25,24±8,97 %, respectively. The rate of persons with the healthy periodontal tissues according to CPI (Community Periodontal Index) was 21,42±21,91 % in children with CEH and 7,14±13,11 % in examined with MIH. In examined with CEH and MIH was fixed the satisfactory hygiene of the oral cavity according to Green-Vermillion index (OHI – Oral Hygiene Index). Conclusion: children with teeth hard tissues formation disorders on the background of digestive diseases need the dispensary observation and course of the therapeutic and prophylactic arrangements for preventing the possible complications (caries, gingivitis, periodontitis).

Optical coherence tomography use in the diagnosis of enamel defects

Molar incisor hypomineralization (MIH) affects the permanent incisors and molars, whose undermineralized matrix is evidenced by lesions ranging from white to yellow/brown opacities to crumbling enamel lesions incapable of withstanding normal occlusal forces and function. Diagnosing the condition involves clinical and radiographic examination of these teeth, with known limitations in determining the depth extent of the enamel defects in particular. Optical coherence tomography (OCT) is an emerging hard and soft tissue imaging technique, which was investigated as a new potential diagnostic method in dentistry. A comparison between the diagnostic potential of the conventional methods and OCT was conducted. Compared to conventional imaging methods, OCT gave more information on the structure of the enamel defects as well as the depth extent of the defects into the enamel structure. Different types of enamel defects were compared, each type presenting a unique identifiable pattern when imaged using OCT. Additionally, advanced methods of OCT image analysis including backscattered light intensity profile analysis and enface reconstruction were performed. Both methods confirmed the potential of OCT in enamel defects diagnosis. In conclusion, OCT imaging enabled the identification of the type of enamel defect and the determination of the extent of the enamel defects in MIH with the advantage of being a radiation free diagnostic technique.

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

BACKGROUND

Molar incisor hypomineralization (MIH) is an idiopathic syndrome that has been associated with several etiologic factors. The authors' objective was to systematically review studies in which the investigators had studied how the etiology of MIH was related to medication intake.

TYPES OF STUDIES REVIEWED

The search covered a period from January 1, 1965, to September 29, 2014. The search revealed 1,042 articles, to which the authors applied eligibility criteria and selected 20 studies for review. The authors considered 9 of the 20 studies to be high quality. The drugs used in these studies were chemotherapeutic drugs, antibiotics, asthma drugs, antiepileptic drugs, antiviral drugs, antifungal drugs, and antiparasitic drugs.

RESULTS

Two reviewers independently performed risk-of-bias assessment and data extraction. The investigators of all of the studies had reported enamel defects, but only 2 sets of investigators had used the term "molar incisor hypomineralization." Owing to the different methodologies used by the investigators of the selected studies, the authors could not perform a meta-analysis of the study results.

CONCLUSIONS

More well-designed prospective studies are needed to clarify the relationship between MIH and medication.

PRACTICAL IMPLICATIONS

It would be convenient to establish a preventive protocol in patients with a potential risk of developing MIH to avoid the complications that are characteristic of this disease.

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.

The prevalence of incisor hypomineralisation and its relationship with the prevalence of molar incisor hypomineralisation

AIM

To establish the prevalence of incisor hypomineralisation (IH) in a cohort of 12-year-old children in Northern England and to relate the prevalence to gender, socioeconomic status, and the prevalence of molar incisor hypomineralisation (MIH).

METHOD

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. A diagnosis of IH was ascribed to any child with a demarcated defect in an incisor but with molar sparing.

RESULTS

3,233 children were examined. The prevalence of IH was 11.0 % (95 % CI 11.0-12.2 %). There was a strong positive correlation between the prevalence of MIH and IH in different regions which reached significance (r = 0.9, p = 0.037) according to Spearman's rho test of correlation. There was a similar pattern of prevalence in the different socioeconomic quintiles although this correlation did not reach significance. The most common teeth affected in IH were the maxillary central incisors, followed by the maxillary lateral incisors and followed by the mandibular incisors. There was no difference in the prevalence of IH by gender.

CONCLUSIONS

The prevalence of IH was 11.0 %. The variation of prevalence between regions and socioeconomic groups and the distribution of lesions in the teeth were very similar to observations seen in MIH children from the same cohort.

XRMA and ToF-SIMS Analysis of Normal and Hypomineralized Enamel

Molar incisor hypomineralization (MIH) is a developmental disturbance of the enamel. This study presents analyses of hypomineralized and normal enamel in first molar teeth diagnosed with MIH, utilizing time-of-flight secondary ion mass spectrometry area analyses and X-ray microanalysis of area and spot profiles in uncoated samples between gold lines which provide electrical conductivity. Statistical analysis of mean values allows discrimination of normal from MIH enamel, which has higher Mg and lower Na and P. Inductive analysis using complete data sets for profiles from the enamel surface to the enamel-dentin junction found that Mg, Cl and position in the profile provide useful discrimination criteria. Element profiles provide a visual complement to the inductive analysis and several elements also provide insight into the development of both normal and MIH enamel. The higher Mg content and different Cl profiles of hypomineralized enamel compared with normal enamel are probably related to a relatively short period during the development of ameloblasts between birth and the 1st year of life.

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.

Prevalence of Molar-Incisor-Hypomineralisation among school children in four German cities

BACKGROUND

A wide range for the prevalence of Molar-Incisor-Hypomineralisation (MIH) has been found in regional studies.

AIM

The aim of this study was to determine the prevalence of MIH in Germany and to compare the findings with other studies.

DESIGN

In the compulsory dental school examination, the first permanent molars, permanent incisors, and second primary molars were examined according to EAPD criteria in 2395 children (8.1 ± 0.8 years) in four regions in Germany for the presence of MIH. Examinations were performed by five calibrated examiners (κ = 0.9) on clean teeth after toothbrushing.

RESULTS

The prevalence of MIH at the four regions differed considerably (4.3-14.6%) with a mean prevalence of 10.1%. The DMFT/dmft was generally low, but children with MIH exhibited statistically significant higher caries values. A total of 12.0% of the children with MIH also had at least one affected primary molar, which resulted in a statistically significant correlation between primary and permanent teeth. Most of the affected teeth had demarcated opacities, but more than half of the affected children showed at least one tooth with severe MIH.

CONCLUSIONS

Molar-Incisor-Hypomineralisation is a prevalent finding in German school children. The prevalence varies highly in different regions, and the high rate of severe forms has clinically relevant implications.

The effect of resin infiltration and oxidative pre-treatment on microshear bond strength of resin composite to hypomineralised enamel

BACKGROUND

Reduced bond strengths of resin composites to hypomineralised enamel increase restorative failure.

AIM

To investigate if the adhesion of resin composite to hypomineralised enamel can be improved by pre-treatments: resin infiltration, oxidative pre-treatment followed by a resin infiltration, or oxidative pre-treatment.

DESIGN

Twenty-one enamel specimens in each of five Groups: 1) Normal enamel; 2) Hypomineralised enamel; 3) Hypomineralised enamel pre-treated with a resin infiltrant, (Icon(®)); 4) Hypomineralised enamel pre-treated with 5.25% sodium hypochlorite then treatment with resin infiltrant; 5) Hypomineralised enamel pre-treated with 5.25% sodium hypochlorite. A resin composite rod was bonded to each specimen using Clearfil™ SE bond as the adhesive (hereafter termed 'routine bonding'), then subjected to microshear bond strength (MSBS) testing.

RESULTS

Overall, the mean MSBS between the five groups differed significantly (P = 0.001). Pre-treatment of hypomineralised enamel with 5.25% sodium hypochlorite with or without subsequent resin infiltration in Groups 4 and 5 prior to routine bonding resulted in increased mean MSBS compared to Groups 2 and 3, with mean MSBS values not differing significantly when compared to routine bonding to normal enamel.

CONCLUSION

Increased bond strength of resin composite to hypomineralised enamel was obtained by pre-treatment of hypomineralised enamel specimens with 5.25% sodium hypochlorite with or without subsequent resin infiltration.