What can impact on the presence of carious lesions in first permanent molars? Revisiting the association between MIH and caries

OBJECTIVE

Assess whether the independent variables (IV) such as number of MIH-affected molars, MIH severity, past caries experience, visible plaque index (VPI), gingival bleeding index (GBI), age, and gender affect the presence of caries lesion (DMF_s) in first permanent molars, considering or not atypical restoration in MIH-affected molars as a previous caries lesion.

METHODS

A sample of 476 schoolchildren, aged 6-10 years, were evaluated for MIH and caries diagnosis, using the Severity Scoring System (MIH-SSS) and the International Caries Detection and Assessment System (ICDAS), respectively. From the ICDAS, the DF-s/ D-s and df-s were calculated. The Zero-inflated Negative Binomial Regression was used to evaluate the impact of the IV on the dependent variable, considering or not the restorative component in MIH-affected molars.

RESULTS

When the presence of caries was evaluated with the restorative component, age, MIH severity and past caries experience had a significant impact on the dependent variable (R2 = 0.176). Without the restorative component in MIH-affected molars, only age and past caries experience were statistically significant (R2 = 0.167).

CONCLUSION

Since in the case of MIH teeth restoration may be attributed to post-eruptive breakdown rather than previous caries lesions, in the present study MIH did not influence the presence of caries lesions in the MIH-affected molars showing that restoration is not an adequate parameter for measuring the historical occurrence of caries.

CLINICAL RELEVANCE

The first permanent molars may not necessarily be at an increased risk of caries due to MIH if the etiological factors for caries development are effectively managed.

Influence of different pre-treatments on the resin infiltration depth into enamel of teeth affected by molar-incisor hypomineralization (MIH)

OBJECTIVES

This in vitro pilot study aimed to evaluate whether different pre-treatments (demineralization, deproteinization, (chemo-)mechanical reduction of the surface layer) influence the penetration depth of a resin infiltrant into MIH-affected enamel compared to initial carious lesions.

METHODS

Thirty extracted human permanent molars with non-cavitated initial carious lesions (n = 5) or MIH (n = 25) were chosen and randomly assigned to six experimental groups: IC: initial caries; M: MIH; MN: MIH, 5.25% sodium hypochlorite; MM: MIH, microabrasion; MA: MIH, air abrasion; MAN: MIH, air abrasion and 5.25% sodium hypochlorite. A modified indirect dual fluorescence staining method was adopted to assess the penetration depth (PD) of the resin infiltrant and the lesion depth (LD) by confocal laser scanning microscopy (CLSM). Exemplarily, scanning electron microscopic (SEM) images were captured. The relationship between group assignment and penetration/lesion depth was estimated using a linear mixed model incorporating the tooth as random effect (two observations/tooth). The significance level was set at p < 0.05.

RESULTS

For MIH-affected molars, the mean PD (in µm; median, [minimum-maximum]) were M (178.2 [32.5-748.9]), MN (275.6 [105.3-1131.0]), MM (48.7 [0.0-334.4]), MA (287.7 [239.4-491.7]), and MAN (245.4 [76.1-313.5]). Despite the observed differences in PD between the groups, these could not be statistically verified (Bonferroni, p = 0.322). The percentage penetration was significantly higher for IC than for MIH groups (Bonferroni, p < 0.05).

SIGNIFICANCE

Compared to IC, resin infiltration into MIH-affected enamel ist more variable. Different pre-treatments influence the resin penetration into developmentally hypomineralized enamel to a fluctuating level.

Knowledge, experience, and perception of molar incisor hypomineralisation among dentists in the metropolitan area of Mexico City: a cross-sectional study

BACKGROUND

Molar-incisor hypomineralisation (MIH) is the most common developmental abnormality observed in teeth. Being a relatively new condition, its treatment can present a challenge for the dentist. There is currently no study available that has evaluated the knowledge of Mexican dental personnel. This study aimed to evaluate the knowledge, experience, and perceptions of dental surgeons regarding the detection, assessment, and treatment of MIH in the metropolitan area of Mexico City.

METHODS

A cross-sectional study was designed. Dentists from Mexico City and its metropolitan area were invited through social networks to answer a questionnaire of 30 questions related to MIH. Participants were classified into general practice dentists, paediatric dentists, and other speciality dentists. Pearson's chi-square test was used for data analysis.

RESULTS

The questionnaire was answered by 391 dentists. A total of 86% (338 out of 391) of them identified MIH lesions, while 84% of them reported having observed MIH lesions in their practice. The most frequently observed lesions were yellow-brown opacities which accounted for 47% of the lesions, 46% were white opacities, while only 7% were observed as post-eruptive fractures in the enamel as part of the manifestations of MIH. The most frequently reported problem in the management of teeth with MIH was insufficient training for treating children with MIH. A total of 84% of dentists stated that they would like more information on the treatment of MIH lesions.

CONCLUSIONS

Most of the surveyed dentists recognised MIH and reported having observed MIH lesions in their practice. Most of the dentists indicated that the main problem for the management of the MIH is the lack of training.

Comparison between two molar incisor hypomineralization detection criteria in epidemiological surveys

BACKGROUND

There is no consensus on which molar incisor hypomineralization (MIH) indices are more suitable for epidemiological surveys.

AIM

To compare the operational aspects and diagnostic ability of the MIH index (simplified/MIH_s and extended/MIH_e) with the MIH-Severity Scoring System (MIH-SSS) in classifying and diagnosing MIH.

DESIGN

This cross-sectional study assessed the indices in a homogeneous group of 680 6- to 10-year-old schoolchildren in Bauru, Brazil, who had at least one first permanent molar, ensuring consistent conditions. Followed by toothbrushing, the children seated on school chairs were examined by the two calibrated researchers under artificial lighting, using mouth mirror and WHO probe, and chronometer recording the duration of examinations.

RESULTS

The prevalence of MIH was 24.7%. The most common characteristic of MIH was demarcated opacity, with a prevalence of 81.7% and 85.45% according to the MIH_s and the MIH-SSS, respectively. A positive association was observed among the MIH_s, the MIH_e, and the MIH-SSS (chi-squared test; p < .01). The MIH-SSS demonstrated a shorter average application time than both versions of the MIH index (ANOVA/Tukey; p < .05). Additionally, fluorosis was found to be the most prevalent among other developmental defects of enamel, with a prevalence of 38.38%.

CONCLUSION

All systems effectively diagnosed MIH and its characteristics.

Molar-Incisor Hypomineralization: Prevalence Comparative Study in 6 Years of Interval

The aim of this study was to evaluate the prevalence evolution rate of MIH (molar-incisor hypomineralization) after a 6-year period in Araraquara/SP, Brazil. This population-based study evaluated MIH in 545 schoolchildren (6-12 years of age) and other associated alterations, dental caries and dental fluorosis (DF). A semistructured questionnaire was sent to the schoolchildren's parents/guardians with the purpose of identifying the socioeconomic profile. Associations between MIH and the clinical characteristics were analyzed by the Poisson analysis of regression with robust variance, estimating the RPc (crude prevalence ratio) with CI 95%. The level of significance of 5% was adopted. The MIH prevalence in Araraquara/SP in 2016 was 14.3% (n = 78), and at this time, an increase of 2% was observed, in comparison with the data of the first prevalence study conducted in 2010 (12.3%). The mild degree compromise was the most prevalent diagnosis in the affected teeth (82.0%). Among children with MIH, the mean number of affected teeth was 2.78. Of the total number of children with MIH, 32.0% presented alterations in both first permanent molars and permanent incisors. There is no significant association between MIH and dental caries experience on permanent dentition (PRc = 1.141; CI 95% 0.709-1.835) or on primary dentition (PR c  = 1.132; CI 95% 0.749-1.709). Children with MIH presented significantly less prevalence of dental fluorosis (PR c  = 0.505; CI 95% 0.268-0.950). There is no association between MIH and monthly Brazilian minimal wage income (PR c  = 1.130; CI 95% 0.655-1.949). It was concluded that the number of MIH cases had increased, revealing a greater need for defining the etiological factors and establishing a correct diagnosis to make it possible to institute early intervention.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Are yellow-brownish opacities in hypomineralized teeth more prone to breakage than white-creamy ones? A systematic review

OBJETIVE

To evaluate all the available evidence assessing if in hypomineralized teeth, yellow-brownish opacities are more prone to post-eruptive breakdown (PEB) compared to white-creamy opacities.

MATERIALS AND METHODS

Observational studies that evaluated the occurrence of PEB in hypomineralized teeth were considered for inclusion. Electronic searches were performed up to January 2022 in MedLine, LILACS, BBO, Cochrane Library, Web of Science, Scopus, and EMBASE. Neither publication date nor language restrictions were imposed to the searches. Two researchers independently performed the study selection, data extraction, and quality assessment of the included studies according to the Newcastle-Ottawa Scale (NOS). Datasets from studies were grouped for narrative synthesis based on the severity of the PEB (enamel or dentin), type of tooth (molar or incisor), unit of analysis (subject or tooth or tooth surface), and follow-up period (in months). The certainty of evidence was evaluated using the GRADE approach.

RESULTS

Nine studies were included, five cohort and three cross-sectional. All studies assessed the opacities and PEB by visual examination and diagnosed MIH according to EAPD criteria. In the cohort studies, considering all follow-up periods (ranging from 6 to 36 months), dark opacities fractured more than light opacities, at both enamel and enamel/dentin levels, and molars fractured more than incisors. In two out of three cross-sectional studies, dark opacities also fractured more than light opacities, but the deep of the PEB (enamel or dentin breakdown) or the type of tooth (molar or incisor) was not considered in the analysis.

CONCLUSION

Although it seems plausible to state that darker demarcated opacities in MIH patients broke more often than light ones, based on this systematic review of the literature, the certainty of the available evidence about this association is still very low.

CLINICAL RELEVANCE

More reliable and valid research is still necessary to support any future recommendation that MIH children who present yellow-brownish opacities should be monitored at shorter intervals compared to those who present only white-creamy opacities.

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.

Survival of stainless-steel crowns and composite resin restorations in molars affected by molar-incisor hypomineralization (MIH)

BACKGROUND

Currently, there is no consensus on the superiority of any material for the restorative treatment of molars affected by molar-incisor hypomineralization (MIH).

AIM

To evaluate the survival of restorations with stainless-steel crown (SSC) or composite resin (CR) in first permanent molars affected by MIH for 24 months.

DESIGN

In this retrospective cohort study, 61 CR and 54 SSC restorations placed on molars affected by MIH of patients, aged between 7 and 10, that were treated and overseen at a university dental clinic in the period of 2017-2020 were evaluated. The primary outcome was the failure-free survival time. Parametric survival models were used for data censored by interval, and the comparison between SSC and CR was performed using the hazard ratio function with a 95% confidence interval.

RESULTS

The survival of SSC and CR restorations after 24 months was 94.4% and 49.2%, respectively. This difference was influenced by the presence of previous restoration (aHR = 3.4; 95% CI: 1.2-9.4) and cusp involvement (aHR = 4.0; 95% CI: 1.5-11.2).

CONCLUSION

In molars with MIH and the need for restorative treatment, SSC had a significantly higher survival rate than CR over 24 months.

Diagnosis training and calibration for epidemiological studies on primary and permanent teeth with hypomineralization

PURPOSE

The objective of this study was to assess the impact on diagnostic accuracy and Kappa values improvement during the three-phase training and calibration process for MIH/HSPM.

METHODS

Thirty dentists were calibrated as examiners for diagnosis of Molar Incisor Hypomineralization (MIH) using Ghanim's index. The whole process was divided into three phases. Phase 1: three meetings with the dentists for the first diagnosis training and calibration (sessions 1a and 1b); phase 2: for a period of 1 month, the dentists started practicing MIH/HSPM diagnosis in the Basic Health Units and an online follow-up group was created to discuss cases and resolve doubts; phase 3: two meetings with the dentists for the second calibration (sessions 2a and 2b). A webpage with educational material was prepared as support during the whole process to improve the dentists' skills in diagnosing MIH/HSPM. The examiners' responses were compared to a gold standard and the Kappa value was obtained.

RESULTS

The average clinical criteria kappa value of the examiners was 0.76 ± 0.19 for the first calibration and 0.93 ± 0.07 (p < 0.05) for the second calibration. For the eruption criteria, the average kappa value was 0.89 ± 0.14 for the first calibration and 0.98 ± 0.08 for the second calibration. Extension criteria had an average kappa value of 0.59 ± 0.15 during the first calibration and 0.75 ± 0.14 during the second calibration.

CONCLUSION

This study demonstrated that the methodology used was an effective tool for improving the diagnostic accuracy of MIH/HSPM.

An update of treatment modalities in children and adolescents with teeth affected by molar incisor hypomineralisation (MIH): a systematic review

PURPOSE

To systematically review the treatment modalities for molar-incisor hypomineralisation for children under the age of 18 years. The research question was, 'What are the treatment options for teeth in children affected by molar incisor hypomineralisation?'

METHODS

An electronic search of the following electronic databases was completed MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, LILACS, Google Scholar and Open Grey identifying studies from 1980 to 2020. The PRISMA guidelines were followed. The studies were screened, data extracted and calibration was completed by two independent reviewers.

RESULTS

Of 6220 potential articles, 34 studies were included. Twenty studies investigated management of molars with fissure sealants, glass ionomer cement, polyacid modified resin composite, composite resin, amalgam, preformed metal crowns, laboratory-manufactured crowns and extractions. In four articles management of incisors with microabrasion, resin-infiltration and a combination of approaches was reported. Eight studies looked at strategies to mineralise MIH-affected teeth and/or reduce hypersensitivity. Two studies investigated patient-centred outcomes following treatment. Due to the heterogeneity between the studies, meta-analysis was not performed.

CONCLUSION

The use of resin-based fissure sealants, preformed metal crowns, direct composite resin restorations and laboratory-made restorations can be recommended for MIH-affected molars. There is insufficient evidence to support specific approaches for the management of affected incisors. Products containing CPP-ACP may be beneficial for MIH-affected teeth.

Best clinical practice guidance for clinicians dealing with children presenting with molar-incisor-hypomineralisation (MIH): an updated European Academy of Paediatric Dentistry policy document

AIM

To update the existing European Academy of Paediatric Dentistry (EAPD) 2010 policy document on the 'Best Clinical Practice guidance for clinicians dealing with children presenting with Molar-Incisor-Hypomineralisation (MIH).'

METHODS

Experts, assigned the EAPD, worked on two different topics: (A) Aetiological factors involved in MIH, and (B) Treatment options for the clinical management of MIH. The group prepared two detailed systematic reviews of the existing literature relevant to the topics and following a consensus process produced the updated EAPD policy document on the 'Best Clinical Practice guidance for clinicians dealing with children presenting with molar-incisor-hypomineralisation (MIH).' The GRADE system was used to assess the quality of evidence regarding aetiology and treatment which was judged as HIGH, MODERATE, LOW or VERY LOW, while the GRADE criteria were used to indicate the strength of recommendation regarding treatment options as STRONG or WEAK/CONDITIONAL.

RESULTS

(A) Regarding aetiology, it is confirmed that MIH has a multifactorial aetiology with the duration, strength and timing of occurrence of the aetiological factors being responsible for the variable clinical characteristics of the defect. Perinatal hypoxia, prematurity and other hypoxia related perinatal problems, including caesarean section, appear to increase the risk of having MIH, while certain infant and childhood illnesses are also linked with MIH. In addition, genetic predisposition and the role of epigenetic influences are becoming clearer following twin studies and genome and single-nucleotide polymorphisms analyses in patients and families. Missing genetic information might be the final key to truly understand MIH aetiology. (B) Regarding treatment options, composite restorations, preformed metal crowns and laboratory indirect restorations provide high success rates for the posterior teeth in appropriate cases, while scheduled extractions provide an established alternative option in severe cases. There is great need for further clinical and laboratory studies evaluating new materials and non-invasive/micro-invasive techniques for anterior teeth, especially when aesthetic and oral health related quality of life (OHRQoL) issues are concerned.

CONCLUSIONS

MIH has been studied more extensively in the last decade. Its aetiology follows the multifactorial model, involving systemic medical and genetic factors. Further focused laboratory research and prospective clinical studies are needed to elucidate any additional factors and refine the model. Successful preventive and treatment options have been studied and established. The appropriate choice depends on the severity of the defects and the age of the patient. EAPD encourages the use of all available treatment options, whilst in severe cases, scheduled extractions should be considered.

Case report of a novel interim approach to prevent early posteruptive enamel breakdown of molar-incisor hypomineralization-affected molars

BACKGROUND AND OVERVIEW

Severely molar-incisor hypomineralization (MIH)-affected teeth are prone to develop early posteruptive enamel breakdown (PEB) and caries. A novel conservative interim approach for the prevention of this complication is presented.

CASE DESCRIPTION

A 6-year-old boy with strong hypersensitivity and extensive brown opacities in the partially erupted mandibular permanent first molars (PFMs) was diagnosed with MIH. Constant hygiene and dietary counseling were followed by the application of luted orthodontic bands and glass ionomer sealants to protect PFMs from caries and PEB until the complete eruption of the teeth. After 36 months, the PFMs were completely erupted, with no caries and PEB, and the cooperation of the child increased.

CONCLUSIONS AND PRACTICAL IMPLICATIONS

Temporary strategies are useful to preserve MIH-affected PFMs. With the methodology described, the hypersensitivity decreased and the patient reached a good degree of cooperation, making possible definitive rehabilitative considerations.

Hypersensitivity in Molar Incisor Hypomineralization: Superficial Infiltration Treatment

To date, there are no standardized protocols available in the literature for hypersensitivity treatment in molar incisor hypomineralization (MIH) patients. The aim of this study was to evaluate the efficacy of erosion–infiltration treatments with resin in children with a strong hypersensitivity and also to develop a minimally invasive diagnostic–therapeutic pathway for young MIH patients. Patients with clinical signs of MIH were enrolled according to international guidelines. A total of 42 patients (8–14 years old) with sensitivity of at least one molar and patients with post eruptive enamel fractures, but without dentin involvement or cavitated carious lesions were selected. A single superficial infiltration treatment with ICON (DMG, Germany) was performed with a modified etching technique. Sensitivity was tested with the Schiff Scale and Wong Baker Face Scale and was repeated at 12 months follow-up. All patients reported lower sensitivity values at the end of the treatment. Significant differences of sensitivity according to the Schiff scale were reported between T0 and all subsequent follow-ups, p < 0.05. The treatment of erosion infiltration with ICON resin is a minimally invasive preventive treatment that significantly improves the problem of hypersensitivity in permanent molars with MIH.

Efficacy of photodynamic therapy, photobiomodulation and antimicrobial agent on the shear bond strength of composite restorations to hypomineralized teeth

PURPOSE

The aim of this study was to investigate the adhesive bond strength and fracture analysis of resin based restorations to carious dentin of hypomineralized molars (HMs) after disinfecting with photodynamic therapy (PDT), Nd:YAG and chlorhexidine (CHX).

MATERIALS AND METHODS

Sixty carious HM molars were investigated. After removal of all carious infected tissue, the cavities were condition with methylene blue initiated PDT, a 1064 nm wavelength Nd:YAG laser or 2.0% CHX gel. Non-carious dentin from HM was used as a control without performing any disinfection or conditioning technique. All samples were bonded using a one-step one-coat adhesive bond over the dentin surface, packed with composite and light cured. All specimens were subjected to thermocycling at 5°C and 60°C with a dwell time of 30 s for 10,000 cycles. Bonded specimens were placed on a universal testing machine with a flat loading head. The debonded surface were viewed under light optical microscope to estimate the type of failure including adhesive, cohesive, and admixed.

RESULTS

The highest mean SBS was seen in the non-carious HM (control group). The mean score for control group was 17.64 ± 2.96 MPa. The lowest bond strength value was displayed for Group-PDT (11.37 ± 3.66 MPa) and Group-Nd:YAG (12.69 ± 2.45 MPa). Affected dentin disinfected with the Group-CHX (15.71 ± 3.04 MPa) bonded with composite showed statistically significantly higher SBS values compared to the laser groups (p < 0.05). No statistically significant difference was noted with specimens disinfected with PDT and Nd:YAG laser showed comparable SBS scores (p > 0.05). Fracture analysis showed equal incidence of adhesive and cohesive failures in control group and Group-CHX. Moreover, a significant number of failures in group-PDT were related to adhesive. Whereas in group 4, admixed type failures were common.

CONCLUSION

Caries infected hypomineralized teeth demonstrated lower bond strength values compared to non-carious hypomineralized teeth. Adhesive bond strength of hypomineralized teeth was highest with chlorhexidine compared to other laser treatment strategies.

Structural integrity of MIH-affected teeth after treatment with fluoride varnish or resin infiltration: An 18-Month randomized clinical trial

OBJECTIVE

To evaluate the influence of fluoride varnish (FV) therapies or resin infiltration (RI) to maintain the structural integrity of Molar Incisor Hypomineralization (MIH) -affected teeth.

METHODS

Fifty-one children aged 6-12 years with at least one incisor and one first permanent molar with yellow/brown MIH opacities were included. Patients were randomly allocated into three groups: FV - Fluoride Varnish (Duraphat); FV+etch - Fluoride Varnish (Duraphat) after enamel etching with 37% phosphoric acid; or RI - Resin Infiltration system (Icon). Opacities were monitored for 18 months. The primary outcome was the loss of integrity due to post-eruptive enamel breakdown (PEB). Covariables included sex, age, DMFT index, opacity colour, plaque index, number of MIH-affected teeth, and number of MIH-affected surfaces. Fisher's Exact was used to test the association of treatments with PEB, the Kaplan-Meyer method analysed the survival rates and Cox-regression determined which covariables would predict failure (α=0.05).

RESULTS

From a total of 235 teeth, the PEB rate for RI (6.1%) was significantly lower (p<0.05) than FV (17.9%; OR 3.0, 95%CI 1.07, 8.48) and FV+etch (17.3%; OR 3.1, 95%CI 1.13, 8.73). DMFT index >3, brown opacities, cusp involvement, and age between 6-8 years predicted PEB (p<0.05).

CONCLUSIONS

Resin infiltration positively influenced the structural integrity maintenance of MIH-affected teeth by decreasing the risk of enamel breakdown over18 months follow-up. Registry of Clinical Trials (RBR-8wwk3n).

CLINICAL RELEVANCE

Resin infiltration proved to be a more efficacious intervention to maintain the structural integrity of MIH-affected teeth than fluoride varnish therapies.

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.

Adhesive restoration of molars affected by molar incisor hypomineralization: a randomized clinical trial

OBJECTIVE

This randomized clinical trial evaluated the survival of direct restorations on first permanent molars (FPMs) with molar incisor hypomineralization (MIH) and its impact on self-reported dental pain and dental anxiety.

MATERIAL AND METHOD

FPMs with MIH of 35 patients aged 7 to 16 years were included. The FPMs were randomized into the following two groups: total-etch (TE-37% phosphoric acid etching) and self-etch (SE-no prior etching). The FPMs were restored with universal adhesive and bulk-fill resin composites. The restoration survival was evaluated according to USPHS criteria modified by a blinded examiner. Dental anxiety (Venham picture test) and dental pain (Faces pain scale-revised) were evaluated before treatment and at 1, 6, and 12 months post-treatment. Survival rates were analyzed by the Kaplan-Meier method and the log-rank test. Nonparametric tests compared pain and anxiety in the follow-up periods.

RESULTS

A total of 64 FPMs were restored (TE = 33; SE = 31). Survival rates were 96.9% (TE) and 96.7% (SE) after 1 month, 90.5% (TE) and 80.6% (SE) after 6 months, and 80.8% (TE) and 62.3% (SE) after 12 months (p > 0.05). Self-reported dental pain and anxiety level decreased after treatment in both groups (p < 0.05). Self-reported pain decreased after 1 month in SE, but it occurred at 6 months in TE.

CONCLUSION

Both restorative protocols presented similar longevity, decreasing self-reported pain and anxiety levels.

CLINICAL RELEVANCE

A universal adhesive could be appropriate for restoration of MIH-affected teeth, and the survival of restorations could be higher in the total-etch technique, reducing dental pain and anxiety.

Prevalence of molar-incisor hypomineralization and other enamel defects and associated sociodemographic determinants in Indiana

BACKGROUND

The aim of this study was to determine the prevalence and severity of molar-incisor hypomineralization (MIH) in a cohort of school-aged children in Indiana.

METHODS

A calibrated examiner screened eligible school-aged children for MIH and other enamel defects. The authors used the integrated Modified Developmental Defects of Enamel Index and the European Academy of Pediatric Dentistry criteria to examine the permanent first molars, permanent incisors, and primary second molars. The authors used descriptive statistics, exact 95% confidence intervals, and χ² tests for analysis (α = 5%).

RESULTS

A total of 337 participants (mean [standard deviation] age, 9.1 (1.7) years; 52% 6 through 8 years; 66% non-Hispanic white) were examined. The prevalence estimate for MIH was 13% as opposed to a 52% prevalence estimate for any enamel defect (AED) of any of the index teeth. Living in an area with water fluoridation levels greater than 0.7 parts per million or being non-Hispanic black was significantly associated with higher prevalence of AED (P < .05) but not with the prevalence of MIH. Demarcated opacities were the most prevalent defects (43%), followed by atypical restorations (32%). Higher age and higher number of MIH-affected surfaces were associated with larger MIH defect extension (P < .05).

CONCLUSIONS

Nearly 1 in 6 children in Indiana had at least 1 permanent first molar with MIH. Water fluoridation levels and race or ethnicity were associated with the prevalence of AED but not with MIH prevalence.

PRACTICAL IMPLICATIONS

US dental practitioners should be cognizant that MIH is a common finding. Children with a high number of MIH-affected surfaces would benefit the most from early identification and management as the extension of the defects tends to worsen with age.

Molar Incisor Hypomineralization: Etiology, Clinical Aspects, and a Restorative Treatment Case Report

CLINICAL RELEVANCE

Total-etch adhesive systems and resin composite are clinically viable dental materials for esthetic restorations in teeth presenting white/yellow/brown hypomineralization stains.

SUMMARY

Molar-incisor hypomineralization (MIH) is a condition that negatively affects enamel and dentin, especially the first molars and permanent incisors, causing esthetic and functional problems. The present clinical case report presents and discusses the etiology and clinical characteristics of MIH and describes a restorative protocol for MIH-affected teeth.

Are the Internet users concerned about molar incisor hypomineralization? An infoveillance study

BACKGROUND

Molar incisor hypomineralization (MIH) is a developmental enamel defect characterized by well-demarcated discolorations frequently detected in molars, causing pain and esthetic alterations.

AIM

To assess the interests of Google users on MIH-related information.

DESIGN

Digital data were collected in Google Trends through two search strategies, 'molar incisor hypomineralization' (topic) and 'MIH' (search term), between January 2004 and November 2018. ARIMA models were applied to analyze trends of curves and to predict the activity of Google users during 12 months. Autocorrelation and partial autocorrelation (ACF/PACF) plots were used to detect trends in the variation of relative search volume (RSV) related to search strategies over time. The most popular queries were analyzed qualitatively, whereas geographical heat maps were retrieved to determine search volumes according to countries (P < .05).

RESULTS

Gradual increasing trends were detected, with forecasts indicating similar levels of RSVs to the period between December 2017 and November 2018. Most popular queries and topics were associated with MIH diagnosis, being retrieved predominantly in European countries.

CONCLUSIONS

The activity of Google users related to this condition is maintained low, with a reduced intensification over time, suggesting that the awareness on MIH is probably confined to dentists and affected people worldwide.

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

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

Hipomineralização molar incisivo em odontopediatria: considerações gerais

Hipomineralização molar incisivo (MIH) engloba a hipomineralização do esmalte que aflige um ou mais primeiros molares permanentes e que pode acometer também incisivos permanentes. Segundos pré-molares e caninos permanentes também podem mostrar-se envolvidos, assim como alguns decíduos, entre os quais cita-se os segundos molares. O objetivo do presente artigo foi averiguar as manifestações clínicas ocasionadas pela hipomineralização molar incisivo sob o enfoque da odontopediatria. Realizou-se estudo de revisão bibliográfica com busca nas bases de dados LILACS e Google Acadêmico. Na base LILACS empregou-se a expressão de busca: hipomineralização molar incisivo and odontopediatria. Na base de dados Google Acadêmico utilizou-se a expressão de busca: hipomineralização molar incisivo and odontopediatria. É importante que se proceda ao diagnóstico precoce e correto da MIH, baseando-se na realização de anamnese detalhada, que seja capaz de investigar a existência de possíveis doenças no período da infância e que se proceda concomitantemente ao feitio de exame clínico para que se estabeleça um prognóstico adequado. Concluiu-se que uma abordagem com cunho preventivo é capaz de minimizar eventuais danos, evitando tratamentos com maior complexidade.

Prevalence of Molar Incisor Hypomineralization among School Children Aged 9 to 12 Years in Virajpet, Karnataka, India

BACKGROUND:

The molar incisor hypomineralization (MIH) is defined as a qualitative defect of the enamel characterised by the progressive and simultaneous hypomineralization of the enamel structure of the first permanent molars which is of systemic origin, which may be associated frequently with incisors. Although the reported prevalence of MIH ranges from 2.4% to 40.2% worldwide, very little data is available from India.

AIM:

To determine the prevalence of molar incisor hypomineralization among school children aged 9 to 12 years in virajpet, Karnataka.

METHODS:

This cross-sectional descriptive study consisted of 1600 school children aged 9-12 years selected by stratified cluster sampling procedure. The European Academy of Pediatric Dentistry criteria were followed for MIH diagnosis. Chi-square test was used to analyse the categorical data. P ≤ 0.05 was considered for statistical significance.

RESULTS:

The prevalence of MIH is 13.12% with no gender predilection. Ten-year-old children showed the highest prevalence (15%) among all the age group. Majority of children with MIH (70.2%) have lesions in both molars and incisors with demarcated opacities and atypical restorations being the most frequent defect type.

CONCLUSION:

Prevalence of MIH was 13.12% in the 9-12-year child population in Virajpet. There is a need for a proper planned preventive and restorative program about the increasing prevalence of MIH.

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

OBJECTIVES

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

CLINICAL RELEVANCE

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

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

OBJECTIVE

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

MATERIAL AND METHODS

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

RESULTS

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

CONCLUSIONS

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

CLINICAL RELEVANCE

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

Survival of sealants in molars affected by molar-incisor hypomineralization: 18-month follow-up

The objective of this study was to evaluate the clinical survival of sealants applied in first permanent molars (FPMs) affected by molar-incisor hypomineralization (MIH), at 18 months of follow-up. Forty-one first permanent molars were selected from 21 children, 6-8 years of age. MIH was classified by one calibrated examiner (kappa = 0.80) according to EAPD criteria. The inclusion criteria were fully erupted FPMs with MIH or sound FPMs (without MIH) for which sealant treatment was indicated. The FPMs were assigned to two groups: CG (control group) and HG (MIH group). Both groups were treated with sealant (FluroShield). Clinical follow-up was performed from baseline to 18 months to assess anatomical form, marginal adaptation, retention and presence of caries, according to criteria set by the United States Public Health Service-Modified, and was conducted by a blinded examiner (kappa = 0.80). The actuarial method was used to evaluate the survival of the sealants. The survival rates for the groups were compared using Fisher's exact test (α = 5%). The cumulative survival rates were 81% at 1 month, 68.8% at 6 months, 68.8% at 12 months, and 62.6% at 18 months for CG, and 88% at 1 month, 84% at 6 months, 76% at 12 months, and 72% at 18 months for HG. No significant difference was found between the groups. The sealants in molars affected by MIH presented a survival rate similar to the sealants in the control, suggesting that sealants may be an adequate approach for preventing carious lesions in MIH-affected molars.

Molar incisor hypomineralization in HIV-infected children and adolescents

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

Eighteen-month clinical performance of composite resin restorations with two different adhesive systems for molars affected by molar incisor hypomineralization

INTRODUCTION

The restorative management of molars with molar incisor hypomineralization (MIH) represents a challenge in the clinical practice with high failure rate.

OBJECTIVE

The aim of this study is to evaluate the clinical survival of direct composite resin restorations in first permanent molars (FPMs) that are affected by MIH, comparing two adhesive systems.

MATERIAL AND METHODS

We selected 41 FPMs with MIH from children aged 6-8 years. FPM fully erupted and with restorative treatment needed were the inclusion criteria. We excluded FPMs with destroyed crowns. The FPMs were randomly assigned to two groups: self-etching adhesive (SEA) and total-etch adhesive (TEA). Clinical evaluation was performed by a blinded examiner during 18 months according to the modified US Public Health Service (USPHS) criteria. The actuarial method was used to evaluate survival of the restorations, and Chi-square and Fisher's exact tests were used to compare differences between the groups (α = 5 %).

RESULTS

The cumulative survival rates were 100 % at 1 month, 89 % at 6 months, 73 % at 12 months, and 68 % at 18 months in SEA, and 95 % at 1 month, 72 % at 6 months, 59 % at 12 months, and 54 % at 18 months in TEA; there was no significant difference between groups.

CONCLUSIONS

There was no difference in clinical survival of restorations in FPMs affected by MIH using TEA or SEA adhesives in the end of 18 months.

CLINICAL RELEVANCE

It was suggested that SEAs as well as TEAs can be applied to restore molars affected by MIH, when it is performed a conservative cavity preparation. Once, cavosurface margins (cavity design) in hypomineralized enamel have less bonding capability.