Etiological Factors of Molar Incisor Hypomineralization: A Systematic Review and Meta-Analysis

Dentin hypersensitivity and toothache among patients diagnosed with Molar-Incisor Hypomineralization: A systematic review and meta-analysis

OBJECTIVES

To determine the prevalence of dentin hypersensitivity (DH) and toothache in patients with Molar-Incisor Hypomineralization (MIH); and evaluate whether patients with MIH have greater likelihood of presenting DH/toothache than controls.

DATA

Studies evaluating DH/toothache in patients with MIH were included. Studies focusing on other enamel defects were excluded.

SOURCES

Eight databases, including grey literature, were searched in January 2024.

STUDY SELECTION

The methodological quality of studies was assessed using the Joanna Briggs Institute checklist for Cross-sectional studies. Proportion and association meta-analyses, subgrouped by diagnostic methods, were conducted. The certainty of evidence was assessed using GRADE approach.

RESULTS

Fifteen studies were included in the qualitative analysis and fourteen in the meta-analyses. Two studies fulfilled all items of the methodological quality checklist. The overall prevalence of DH/toothache among patients with MIH was 45 %. Prevalence rates of 30 %, 47 %, and 55 % were estimated based on proxy reports, self-reports, and air stimulation, respectively. The overall prevalence of DH/toothache per tooth was 22 %, ranging from 16 % to 29 % according to the diagnostic method. Patients with MIH demonstrated higher likelihood of presenting proxy reports of DH/toothache compared to those without MIH (OR: 1.51, 95 % CI [1.23-1.85], P < 0.01, I2: 0 %). The certainty of evidence was very low, mainly due to the low methodological quality of included studies and high inconsistency.

CONCLUSIONS

The global prevalence of DH/toothache was 22 %, per tooth, and 45 % per patient. Estimates vary according to diagnostic methods. Patients with MIH showed higher likelihood of presenting proxy reports of DH/toothache than controls.

CLINICAL SIGNIFICANCE

This systematic review contributes valuable information to the dental literature by assessing the prevalence and associated factors of DH/toothache in patients with MIH. The findings can guide future research, inform clinical practices and public policy makers, and ultimately improve the management of oral health of patients with MIH.

REGISTRATION

PROSPERO CRD42023432805.

Preventive efficacy of 38% silver diamine fluoride and CPP-ACP fluoride varnish on molars affected by molar incisor hypomineralization in children: A randomized controlled trial

Background

This randomized controlled trial aimed to compare the efficacy of silver diamine fluoride (SDF) and Casein Phosphopeptide-Amorphous Calcium Phosphate fluoride Varnish (CPP-ACPFV) in preventing caries development, enamel breakdown, and sensitivity on molars affected by molar incisor hypomineralization (MIH) in children.

Methods

A total of 100 children aged 6 to 9 years were enrolled in the study with two contralateral permanent molars mildly affected by MIH. Affected molars were randomly and equally assigned to receive either SDF or CPP-ACPFV treatment. The interventions were applied at four different time points (baseline, 3, 6, 9 months), and the incidence of caries, caries progression, enamel breakdown, and sensitivity were assessed.

Results

The findings of this study revealed significant differences in the incidence of caries between the groups treated with SDF and CPP-ACPFV ( P-value < 0.05). Similarly, there was a significant difference in caries progression between the two groups ( P-value < 0.05). However, no significant differences were observed in enamel breakdown scores between the treatment groups, as the majority of teeth in both groups exhibited a score of 0. Furthermore, there were no significant differences in sensitivity between the treatment groups throughout the study period.

Conclusions

In conclusion, the results of this study provide evidence that molars treated with SDF demonstrated a lower incidence of caries and a higher rate of caries arrest compared to those treated with CPP-ACPFV. Both interventions showed promise in preventing enamel breakdown and improving sensitivity. These findings highlight the potential of SDF and CPP-ACPFV as effective treatments for caries prevention and management, emphasizing the importance of early intervention and appropriate dental care strategies in maintaining oral health.

Trial registration

ISRCTN54243749 (13/01/2022).

Association of Three Genetic Loci with Molar Incisor Hypomineralization in Polish Children

BACKGROUND

Molar incisor hypomineralization (MIH) is a qualitative, demarcated enamel defect of hypomineralization affecting one to four first permanent molars, often with incisor involvement. Its etiology is complex. However, evidence suggests the influence of genetic factors, potentially including the single nucleotide polymorphisms (SNPs) rs2889956, rs4811117 and rs13058467, which were previously linked to MIH in a genome-wide association study of German children. The aim was to replicate analyses of possible associations between the SNPs and molar incisor hypomineralization in Polish children.

METHODS

The final study group consisted of 778 children aged 126-168 months old. Saliva samples were taken, and genomic DNA was extracted and genotyped using beadchip microarrays.

RESULTS

Among the 778 subjects, there were 68 (8.7%) subjects with MIH and 710 (91.3%) subjects without MIH. There were no significant differences in distributions in age, sex, or the frequency of caries in permanent dentition between the MIH and non-MIH groups. The rs2889956, rs4811117, and rs13058467 genotype distributions in the studied group conformed to the expected Hardy-Weinberg equilibria, and there were no significant differences in the distributions of their alleles or genotypes between the MIH and non-MIH groups.

CONCLUSION

Our replication study did not confirm highly significant associations between the single nucleotide polymorphisms rs2889956, rs4811117, and rs13058467 with molar incisor hypomineralization in Polish children.

Relationship between cariogenic bacteria and molar incisor hypomineralization in Brazilian schoolchildren

Background

Teeth with defects in their structure, such as the ones affected by molar-incisor hypomineralization (MIH), are more susceptible to carious lesions. Caries is a complex and multifactorial disease highly prevalent in childhood. The present research evaluated the relationship between the stages of MIH and cariogenic bacteria in children.

Methods

After examining 566 schoolchildren, four groups of 10 children each were formed: healthy (G1), mild MIH (G2 and G3), and severe MIH + caries (G4). Dental biofilm was assessed to quantify Streptococcus mutans (SM) and Lactobacillus spp. (LB) using real-time polymerase chain reaction (RT-PCR).

Results

LB counting in biofilm samples of healthy children (G1) and those with mild MIH characterized by white opacities (G2) were not significantly different. The same happened when the ones with yellow opacities (G3) were compared with severe MIH + caries (G4) (P>0.05). The post hoc Tukey test proved that G4 had greater levels of SM and LB when compared with G2 (P<0.05); however, the control group did not diverge from the others considering SM (P>0.05). Increased LB enhanced the severity of MIH [rate ratio (RR): 7.706; P=0.035].

Conclusions

LB was influenced by different degrees of MIH and the presence of caries and could guide clinical decisions and patients' recommendations to prevent carious lesions in MIH children.

Contemporary Understanding of the Etiology and Management of Molar Incisor Hypomineralization: A Literature Review

Molar incisor hypomineralization (MIH) is a significant health problem that can affect the child's quality of life by negatively affecting their esthetics and function. This review aimed to summarize the etiology and pathogenesis of MIH. It also aimed to summarize the recent studies on MIH in children and adolescents, focusing on diagnosis, prevention, and clinical management. An electronic search on the PubMed, Cochrane Database of Systematic Reviews, MEDLINE, MedlinePlus, WHO reports, and Google Scholar databases was performed. The volume of research on the etiology, presentation, and clinical management of MIH is still expanding. The creation and validation of indices for the diagnosis and management of MIH, as well as any potential genetic aspects appear to be the main areas of current research. Notably, MIH was linked to childhood illnesses, the use of antibiotics, and early childhood fever. Although many studies discuss the different options for managing MIH lesions, evidence-based studies that address the long-term outcomes of MIH are still lacking. Indeed, future clinical studies should be directed to evaluate the impact of each systemic etiological factor and its different types of management on normal amelogenesis. Regarding the diagnosis, future research should focus on the pre-eruption diagnosis and early approaches to prevent the post-eruption breakdown and caries. Regarding the treatment of MIH, future investigations should emphasize further improvements in adhesion and the use of new materials and techniques, such as digital dentistry.