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

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

OBJECTIVE

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

MATERIAL AND METHODS

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

RESULTS

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

CONCLUSION

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

Knowledge and perception regarding molar incisor hypomineralisation among dental students and dental hygienist students in Spain: a cross-sectional study

BACKGROUND

Molar incisor hypomineralisation (MIH) has a high prevalence in the Spanish pediatric population and is a precursor of carious lesions in teeth in which it is present. Although this pathology is included in the curricula of the Degree in Dentistry and the Training Cycle in Oral Hygiene in our country, the contents currently taught seem to be insufficient in relation to the level of knowledge that we have today about this condition.

METHODS

A digital questionnaire of 18 questions was sent to a sample of 448 students attending the 4th and 5th year of the Degree in Dentistry and 2nd year of the Training Cycle in Oral Hygiene from different universities and vocational training centers in the Valencian Community. Descriptive and multivariate statistical analysis of the data was subsequently performed.

RESULTS

Of the 290 questionnaires that were obtained, 53.8% were from students attending the 2nd year of a training course in oral hygiene and 46.2% were from students pursuing a degree in dentistry. Most of the respondents had heard about MIH (75.2%), mainly through master classes. However, most students had difficulties distinguishing MIH lesions from other lesions (58.3%). The degree of knowledge about MIH was greater among dental students in all the aspects evaluated: prevalence, diagnosis, prevention, and treatment. Of all the students, 83.8% were interested in increasing their training on MIH, especially in the areas of diagnosis and treatment.

CONCLUSION

The results of the present study justify the need to expand the content on MIH, both theoretical and practical, in the educational curricula of the Degree in Dentistry and Integrated Vocational Training Centers in Spain.

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

OBJECTIVE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

Evaluation of antimicrobial photodynamic therapy and minimal intervention associated with deproteinisation in permanent teeth with molar incisor hypomineralisation: study protocol for a clinical, controlled, blinded trial

INTRODUCTION

Molar incisor hypomineralisation (MIH) is a qualitative defect of enamel development that occurs in the mineralisation phase. MIH affects one or more permanent molars and, occasionally, permanent incisors. The aim of the proposed study is to evaluate the clinical effect of antimicrobial photodynamic therapy (aPDT) on permanent teeth with MIH through decontamination and sensitivity control.

METHODS AND ANALYSIS

Patients from 8 to 12 years of age with permanent molars will be randomly allocated to three groups. Group 1: selective chemical-mechanical removal of carious dentinal tissue around the walls of the cavity with Papacárie Duo and a curette followed by the application of aPDT and deproteinisation with Papacárie Duo; group 2: selective removal of carious dentinal tissue around the walls of the cavity with a curette, followed by the application of aPDT and deproteinisation with a 5% sodium hypochlorite solution; group 3: selective removal of carious dentinal tissue using a curette. The selected teeth must have a carious lesion in the dentin and posteruptive enamel breakdown on one or more surfaces with an indication for clinical restorative treatment. The teeth will subsequently be restored using a mixed technique with resin-modified glass ionomer cement and bulk-fill composite resin. The data will be submitted to descriptive statistical analysis. Associations with age and sex will be tested using either the χ2 test or Fisher's exact test. Pearson's correlation coefficients will be calculated to determine the strength of correlations between variables. Comparisons of the microbiological results (colony-forming units) will be performed using analysis of variance and the Kruskal-Wallis test. Kaplan-Meier survival analysis will be performed to assess the performance of the restorations.

ETHICS AND DISSEMINATION

This protocol has been approved by the Human Research Ethics Committee of Nove de Julho University (certificate number: 61027522.0.0000.5511/approval date: 23 August 2022). The findings will be published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT05443035.

Developmental enamel defects and their relationship with caries in adolescents aged 18 years

Randomly selected 1,611 individuals aged 18 years formed a nationally representative sample from all provinces of Poland. Developmental defects of the enamel (DDE) and caries were assessed using the modified DDE index, molar incisor hypomineralisation (MIH) Treatment Need Index (MIH-TNI), FDI and WHO criteria by 22 trained and calibrated dentists. T-test was used for comparing group means. A simple and multiple logistic regression tests were used to assess the relationship between DDE and caries severity expressed as DMFT (p < 0.05). The prevalence of DDE was 13.7%. Demarcated opacities (DEO) were the most frequent (9.65%); 4% had diffuse opacities (DIO) and 1.5% had hypoplasia. MIH was diagnosed in 0.6% patients. The prevalence of caries was 93.2%, with mean DMFT of 6.50 ± 4.22. The DMFT value was 7.52 ± 4.77 in the group of patients with demarcated opacities (DEO); 7.85 ± 4.74 with diffuse opacities (DIO) and 7.56 ± 4.57 with enamel hypoplasia, respectively. There was a significant relationship between caries severity and DDE (p < 0.001), DEO (p = 0.001) and DIO (p = 0.038), and between DDE and DMFT index (p < 0.001). The results obtained in the study proved the significant relationship between DDE and DMFT in 18-year-olds, the assessment of which was the aim of the study.

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

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

Systematic review registration

https://osf.io/un76d.

Dental and Dental Hygiene Students' Knowledge and Capacity to Discriminate the Developmental Defects of Enamel: A Self-Submitted Questionnaire Survey

Background: A prompt and accurate diagnosis of developmental defects of enamel (DDE) is mandatory for proper treatment management. This cross-sectional survey, designed and carried out using anonymous self-administered questionnaires, aimed to assess dental and dental hygiene students’ knowledge and their capability to identify different enamel development defects. Methods: The questionnaire consisted of twenty-eight closed-ended questions. Two different samples of undergraduate students were selected and enrolled: a group of dental hygiene (GDH) students and a group of dental (GD) students. A multivariate logistic regression was performed by adopting the correct answers as explanatory variables to assess the difference between the two groups. Results: Overall, 301 completed questionnaires were analyzed: 157 from the GDH and 144 from the GD. The dental student group showed better knowledge than the GDH of enamel hypomineralization and hypoplasia (p = 0.03 for both). A quarter (25.25%) of the total sample correctly identified the period of development of dental fluorosis with a statistically significant difference between the groups (p < 0.01). Amelogenesis imperfecta (AI) was identified as a genetic disease by 64.45% of the sample, with a better performance from the GD (p = 0.01), while no statistical differences were found between the groups regarding molar incisor hypomineralization. Multivariate analysis showed that AI (OR = 0.40, [0.23;0.69], p < 0.01) and caries lesion (OR = 0.58, [0.34;0.94], p = 0.03) were better recognized by the GD. Conclusions: Disparities exist in the knowledge and management of DDE among dental and dental hygiene students in Italy; however, significant knowledge gaps were found in both groups. Education on the diagnosis and treatment of DDE during the training for dental and dental hygiene students needs to be strongly implemented.

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.

The effect of melatonin on the mouse ameloblast-lineage cell line ALCs

Melatonin plays a critical role in promoting the proliferation of osteoblasts and the growth and development of dental papilla cells. However, the effect and mechanism of melatonin on the growth and development of ALCs still need to be explored. CCK8 assay was used for the evaluation of cell numbers. qRT-PCR was used to identify the differentially expressed genes in ALCs after melatonin treatment. The number and morphology of ALCs were investigated by confocal microscopy. Alkaline phosphatase assay and Alizarin red S staining were used for measuring mineralization. Then, we focused on observing the crucial factors of the signaling pathway by RNA-seq and qRT-PCR. Melatonin limited the cell number of ALCs in a dose-dependent manner and promoted the production of actin fibers. A high concentration of melatonin significantly promoted the mRNA levels of enamel matrix proteins and the formation of mineralized nodules. RNA-seq data showed that Wnt signaling pathway may be involved in the differentiation of ALCs under the influence of melatonin. This study suggests that melatonin plays a regulatory role in the cell number, differentiation, and mineralization of the ALCs, and then shows the relationship between the Wnt signaling pathway with the ALCs under melatonin.

Molar Incisor Hypomineralization—Influence on Dental Caries Experience Indexes: A Cross-sectional Study

Aim and and objective

To evaluate the influence of the clinical characteristics inherent to Molar Incisor Hypomineralization on the values ​​and scores of the DMF-T and ICDAS indexes.

Materials and methods

Eight hundred and eight seven teeth were examined, from 39 individuals aged 3-14 years (8.95 ± 3.26), who had at least one first permanent molar (FPM) or second primary molar with signs of hypomineralization, according to the criteria of the European Academy of Paediatric Dentistry. Hypomineralized teeth were evaluated for the presence of restorations, post-eruptive breakdowns (PEB), and dental caries, being considered sound for the DMF-T when there was the presence of PEB without caries lesion. Chi-square and Kruskal Wallis tests (p ≤ 0.05) were used to detect differences.

Results

Two hundred and five teeth showed signs of hypomineralization. The average number of opacities was influenced by the period of dentition, with more opacities when the primary dentition and the eruption of FPM and permanent incisors were complete (p ≥ 0.05). Hypomineralized teeth showed a higher DMF-T value, mainly of the decayed component (12%), in contrast to 2.5% of nonhypomineralized teeth. It was not possible to associate ICDAS scores 1 and 2 to hypomineralized surfaces, due to the overlap with the diagnosis of early enamel caries. The values ​​of this index changed in the presence of cavitation by caries (scores 3,4,5,6), but not in the presence of PEB.

Conclusion

Due to the impossibility of differential diagnosis with caries lesion, PEB, and opacities present in hypomineralized teeth tend to overestimate the values ​​and scores of the DMF-T and ICDAS, respectively.

Clinical significance

Make future suggestions for epidemiological studies in the area.

How to cite this article

Vieira FG, Pintor AV, Silva FD, et al. Molar Incisor Hypomineralization—Influence on Dental Caries Experience Indexes: A Cross-sectional Study. Int J Clin Pediatr Dent 2022;15(1):65-68.

Relationship between molar incisor hypomineralization, intrapartium medication and illnesses in the first year of life

Molar incisor hypomineralization (MIH) affects the first permanent molars and permanent incisors whose formative embryological process develops around birth and the first year of life. This study’s main objective is to assess the relationship between MIH, on the one hand, with the administration during childbirth of epidural bupivacaine, intramuscular meperidine with haloperidol, synthetic intravenous oxytocin, and prostaglandins such as dinoprostone vaginally, and on the other hand, with suffered pathologies during the first year of life. Cross-sectional retrospective study was carried out on 111 children who attended dental check-ups. Oral examination was carried out to determine MIH involvement. Data on the administration of medications during delivery and the illnesses suffered by the children in the first year of life were taken from the hospital records. Significant relationship with Pearson's chi-square was found between the presence of MIH and the administration of meperidine with haloperidol intramuscularly and the vaginal administration of dinoprostone during labour. Also in children who have suffered serious infections and those who have received antibiotics in early childhood. In recent years there has been a growing trend in many countries to medicalize childbirth even above what the World Health Organization recommends. Some of the drugs used in these protocols could be involved in the appearance of dental mineralization alterations of the MIH type and this would help to explain the increase in its prevalence.

Melatonin-Medicated Neural JNK3 Up-Regulation Promotes Ameloblastic Mineralization

Introduction: Melatonin, an endogenous neurohormone, modulates the biological circadian rhythms of vertebrates. It functions have been reported in previous stomatological studies as anti-inflammation, antioxidant, osseointegration of dental implants and stimulation to dental pulp stem cells differentiation, but its role in ameloblastic differentiation and mineralization has been rarely studied. Objective: To reveal the effects of melatonin on the mineralization of ameloblast lineage cells (ALCs), and to identify the change in gene expression and the potential mechanism based on ribonucleic acid sequencing (RNA-seq) analysis. Method: ALCs were induced in melatonin-conditioned medium. After 7-days culture, Western blot, real-time PCR, alkaline phosphatase (ALP) activity test, RNA-seq were accordingly used to detect the change in molecular level. After 1-month odontogenic induction in melatonin medium, Alizarin Red-S (ARS) staining showed the changes of mineral nodules. Differentially expressed genes (DEGs), enrichment of functions and signaling pathways analysis based on Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) database were performed. The JNK3 antagonist (JNK3 inhibitor IX, SR3576) and β-arrestin1 (Arrb1) overexpression were applied to confirm the fluctuation of melatonin-medicated JNK3 and Arrb1 expression. Results: In this study, we found out melatonin contributed to the ameloblastic mineralization, from which we can observed the elevated expression of enamel matrix protein, and increased ALP activity and mineralized nodules formation. RNA-seq analysis showed the up-regulation of neural JNK3 and down-regulation of Arrb1 in ALCs. Meanwhile, phosphorylated JNK3 deficiency (phosphorylated JNK3 inhibitor---SR3576 added to culture medium) led to mineralization delay, and Arrb1 overexpression proved Arrb1 takes bridge between melatonin receptors (MTNR) and JNK3 in MAPK signaling pathway.

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.

Is there an association between dental caries, fluorosis, and molar-incisor hypomineralization?

Objective:

This cross-sectional study aimed to determine the prevalence of dental caries, dental fluorosis, and molar-incisor hypomineralization, and their associations in a group of Brazilian schoolchildren.

Methodology:

Adolescents (n=411) were evaluated by two calibrated examiners for dental caries (DC), dental fluorosis (DF), and molar-incisor hypomineralization (MIH) using the CAST (Caries Assessment Spectrum and Treatment) instrument, Thylstrup and Fejerskov (TF) index, and MIH Severity Scoring System (MIH-SSS), respectively. Descriptive statistics, chi-square tests, and logistic regression were used for statistical analysis.

Results:

The sample comprised 42.75% boys and 57.25% girls. The prevalence of DC in permanent dentition was 94.75%, of which 29% were represented by dentin lesions. For DF, a prevalence of 40.75% was observed, with 69.32% mild, 12.88% moderate, and 17.79% severe. A positive association between the source of water and fluorosis was detected (p=0.01). The prevalence of MIH was 18%. Thirty adolescents (41.7%) presented with severe MIH. No association was found between DF or MIH and dentin DC or between MIH and DF at the individual level. However, a significant negative relationship was detected between DF and dentin carious lesions ( p <0.005) and DF and MIH ( p <0.00001) at the tooth level, whereas a positive association was observed between MIH and dentin carious lesions ( p <0.00001). A positive association was also observed between the severity of both conditions ( p <0.00001). Mild DF was the most prevalent problem observed. Cases of teeth with mild MIH were the most predominant in MIH-affected teeth.

Conclusions:

No association was observed among the dentin carious lesions, MIH, and DF at the participant level. However, a positive association between MIH and dentin carious lesions was found at the tooth level, whereas MIH, DF, and DF and dentin carious lesions showed a negative relationship.

Molar Incisor Hypomineralization: Clinical Characteristics with Special Emphasis on Etiological Criteria

Molar incisor hypomineralization (MIH) is an entity to describe the enamel defects of the first permanent molars with the involvement of one or more incisors due to an underlying systemic cause. It is a frequently encountered challenge by dentists in a dental clinic and dental complications affecting patient's quality of life. Early diagnosis is the key to protect and prevent the deterioration of the condition. This article aims to highlight different aspects of etiology to treatment options in young patients related to MIH.

Efficacy of low-level laser therapy associated with fluoride therapy for the desensitisation of molar-incisor hypomineralisation: Randomised clinical trial

BACKGROUND

Molar-incisor hypomineralisation (MIH) is a qualitative enamel defect.

AIM

To investigate the low-level laser therapy (LLLT) associated with fluoride varnish for the desensitisation of teeth with MIH.

DESIGN

A randomised clinical trial was conducted with 66 children, randomly allocated to the treatments: laser (L); fluoride varnish (FV); and laser + fluoride varnish (L + FV). The participants in the L group underwent two sessions of LLLT (48-hour interval). The FV group received four applications of varnish at one-week intervals. The L + FV underwent two sessions of LLLT and four applications of varnish. Prior to each session and one month after the onset of treatment, tooth sensitivity and its magnitude were evaluated. Intra- and inter-group comparisons were performed (α = 5%).

RESULTS

A significant reduction in the mean sensitivity score was found over time in all groups. After the final treatment, a significant difference was found between the L and L + FV groups (P = .011), with a lower score in the L + FV group (0.09), whereas no difference was found between the FV and L + FV groups (P = .095).

CONCLUSIONS

Fluoride varnish and the combination of treatments (L + FV) had greater desensitising action on teeth with MIH. Laser therapy demonstrated an immediate desensitising effect, whereas fluoride varnish had a late-onset effect.

ENAM Gene Variation in Students Exposed to Different Fluoride Concentrations

The ENAM gene is important in the formation of tooth enamel; an alteration can affect the lengthening of the crystals, and the thickness in enamel. The objective was to determine the presence of the single nucleotide variant (SNV) rs12640848 of the ENAM gene in students exposed to different concentrations of fluoride.

METHODS

A cross-sectional study was conducted on students exposed to high concentrations of fluoride in the city of Durango which were divided according to the severity of fluorosis and dental caries. Genotype determination was performed by DNA sequencing. The relationship between the severity of dental fluorosis and the allele distribution was determined by the Fisher's exact and Kruskal-Wallis tests.

RESULTS

Seventy-one students were included for the sequencing. In the different allelic variations, for the normal genotype AA/TT, the control group presented 75%, for the AG/TC variation, 70.8% in the TF ≤ 4 group, 65% in TF ≥ 5, and 16.7% in TF = 0; with respect to GG/CC variation, 12.5% in TF ≤ 4, 22% in TF ≥ 5, and 8.3% in TF = 0 group (p = 0.000).

CONCLUSION

The ENAM gene showed an association in the population exposed to different concentrations of fluoride.

Prevalence and Severity of Molar-Incisor Hypomineralization, Maternal Education, and Dental Caries: A Cross-Sectional Study of Mexican Schoolchildren with Low Socioeconomic Status

Objectives

The aims of this study were to identify the prevalence of molar-incisor hypomineralization (MIH) in a group of low-income schoolchildren and to evaluate the role of maternal education on MIH and dental caries in these children.

Materials and Methods

This cross-sectional study enrolled 686 schoolchildren. To evaluate dental caries, the International Caries Dental Assessment System II (ICDAS) criteria were utilized. MIH was assessed by using the European Academy of Paediatric Dentistry criteria. Mixed-effects models were applied for the data analysis.

Results

The prevalence of MIH was 35.4% (244). Most children exhibited moderate MIH (163, 67.1%), followed by mild MIH (45, 18.5%) and severe MIH (35, 14.4%). Caries presence in the first permanent molars, evaluated using ICDAS score, indicated that the mean number of noncavitated and cavitated lesions (ICDAS ≥2) was 0.90 (±0.30); the mean number of lesions with ICDAS ≥3 was 0.36 (±0.48). Odds ratio (OR) analysis of MIH severity revealed that the children of mothers with low education were more likely to exhibit MIH (OR 2.13; 95% confidence interval [CI]: 1.25-3.85). Modeling of dental caries (ICDAS ≥3) revealed that low maternal education (OR 2.27; 95% CI: 1.25-4.16) and the presence of MIH (OR 4.37; 95% CI: 3.05-6.25) were associated with dental caries.

Conclusions

There were associations between low maternal education and both MIH and dental caries. The presence of both initial and cavitated caries lesions was associated with MIH. Dentists should offer adequate advice to mothers with children with MIH, based on their educational background.

Dental anxiety in schoolchildren with molar incisor hypomineralization-A population-based cross-sectional study

BACKGROUND

Identifying patients with high levels of DA helps to define the most adequate oral healthcare strategy, especially for pediatric patients.

AIM

To investigate the association between parental reports of dental anxiety (DA) and molar incisor hypomineralization (MIH) in schoolchildren.

DESIGN

A cross-sectional study was conducted in a representative sample of 731 8-year-old schoolchildren from the city of Curitiba, Brazil, who were clinically examined (k ≥ 0.75) for the diagnosis of MIH and dental caries using the EAPD criteria and dmft/DMFT index, respectively. Parents/guardians reported children's DA using the Dental Anxiety Question (DAQ) and answered a self-administered structured questionnaire addressing socioeconomic and demographic characteristics. Associations were evaluated using Poisson regression analysis with robust variance (P < 0.05).

RESULTS

A significant association was found between DA and MIH (PR = 1.20; 95%CI: 1.01-1.42; P = 0.038), but this association lost its significance when adjusted for the other characteristics (PR = 1.13; 95%CI: 0.93-1.38; P = 0.215). Caries experience in primary teeth was associated with lower levels of DA (PR = 0.83; 95%CI: 0.71-0.96; P = 0.0013). The most recent visit to the dentist due to pain increased the levels of DA (PR = 1.18; 95%CI: 1.07-1.30; P = 0.001).

CONCLUSIONS

The presence of MIH in schoolchildren was not associated with parental reports of DA.