The effect of iron deficiency anemia on experimental dental caries in mice

Iron Status and Risk of Periodontitis and Dental Caries: A Mendelian Randomization Study

BACKGROUND

Previous studies have indicated a potential relationship between iron status and oral health outcomes, specifically periodontitis and dental caries. This study employed Mendelian randomization (MR) to investigate the causal effects of iron status on these oral health conditions. The focus of this study was on key iron biomarkers, namely serum iron, ferritin, transferrin saturation (TSAT), and total iron-binding capacity (TIBC).

METHODS

This two-sample MR analysis employed genome-wide association study (GWAS) data. The instrumental variables (IVs) were selected based on their genome-wide significance and independence from confounders. The statistical analyses employed the inverse variance weighted (IVW) method, MR-Egger regression, weighted median, and weighted mode. Additionally, sensitivity analyses were conducted to verify the reliability of the causal association results.

RESULTS

The MR analysis indicated a suggestive negative causal relationship between TIBC and periodontitis, with an odds ratios of 0.875 and a 95% CI of 0.766-0.998, with a P-value of .047. No significant other associations were found. The results of sensitivity analyses demonstrated the robustness of these findings.

CONCLUSION

This MR study suggested a potential negative association between TIBC and periodontitis, highlighting the importance of considering iron status in the clinical management of chronic periodontitis. However, more standardized, multi-population studies are needed to confirm this causality.

Iron Level in Pregnant Rats is Associated with Caries Susceptibility in Offsprings

Iron deficiency anemia (IDA) is a prevalent issue in pregnant women and children. However, the causal relationship between IDA in pregnancy and caries susceptivity in offspring remains unclear. This study aimed to explore the role of iron level during pregnancy on caries susceptivity of offsprings. Here, low-iron (LI) and high-iron (HI) models were established in maternal rats, and iron-related characteristics were examined in maternal rats and their offsprings. After induction of caries in rat offsprings, the carious lesions were evaluated by the Keyes scores, and microstructural damages in molars were observed by scanning electron microscopy. The results showed that LI in maternal rats induced IDA in rat offsprings, and HI only increased serum ferritin in offsprings. LI and HI in maternal rats had no effect on the morphological structure of salivary glands in rat offsprings. After inducing caries, rat offsprings in the LI group exhibited significant increase in enamel lesions at the smooth surface, and on enamel, slight dentinal, and moderate dentinal lesions at the sulcal surface. Only enamel lesions at the sulcal surface were significantly weakened in the HI group. Additionally, visible enamel damages were observed in the LI group. To sum up, iron deficiency during pregnancy enhances caries susceptibility in rat offsprings.

Iron Deficiency Anemia and Its Impact on Oral Health-A Literature Review

Oral disease interventions primarily focus on behavioral changes like dietary improvements and ensuring better oral hygiene. However, recognizing the influence of biological factors, including genetics and early-life nutrition, is crucial. Iron deficiency (ID) and its advanced form, iron deficiency anemia (IDA), affect nearly two billion people globally, especially children and pregnant women. We conducted a comprehensive search using Medline via EndNote and Web of Science, employing keywords related to iron deficiency anemia (IDA), and we identified 36 studies deemed relevant for inclusion in this literature review. IDA prevalence is notably high among pregnant women and young children. Both IDA and early-childhood caries (ECC) disproportionately affect impoverished populations, highlighting the socioeconomic dimension of this issue. IDA presents with various oral mucosal changes and is closely linked to candidiasis. Additionally, IDA can hinder tooth development and weaken the immune response. Multiple population surveys have revealed a significant association between ECC and IDA. While some studies have explored the IDA-periodontal disease link, the current evidence is relatively limited in its robustness. In conclusion, more comprehensive longitudinal studies are essential to deepen our understanding of the IDA-oral disease connection. Investigating the underlying biological mechanisms is critical to developing effective interventions, particularly for vulnerable populations affected by IDA.

An Update on Drug-Nutrient Interactions and Dental Decay in Older Adults

In recent decades, the global demographic landscape has undergone a discernible shift that has been characterised by a progressive increase in the proportion of elderly individuals, indicative of an enduring global inclination toward extended lifespans. The aging process, accompanied by physiological changes and dietary patterns, contributes to detrimental deviations in micronutrient consumption. This vulnerable aging population faces heightened risks, including dental caries, due to structural and functional modifications resulting from insufficient nutritional sustenance. Factors such as physiological changes, inadequate nutrition, and the prevalence of multiple chronic pathologies leading to polypharmacy contribute to the challenge of maintaining an optimal nutritional status. This scenario increases the likelihood of drug interactions, both between medications and with nutrients and the microbiome, triggering complications such as dental decay and other pathologies. Since the drug industry is evolving and new types of food, supplements, and nutrients are being designed, there is a need for further research on the mechanisms by which drugs interfere with certain nutrients that affect homeostasis, exemplified by the prevalence of caries in the mouths of older adults. Infectious diseases, among them dental caries, exert serious impacts on the health and overall quality of life of the elderly demographic. This comprehensive review endeavours to elucidate the intricate interplay among drugs, nutrients, the microbiome, and the oral cavity environment, with the overarching objective of mitigating the potential hazards posed to both the general health and dental well-being of older adults. By scrutinising and optimising these multifaceted interactions, this examination aims to proactively minimise the susceptibility of the elderly population to a spectrum of health-related issues and the consequences associated with dental decay.

Association between serum biomarkers and oral health status in children with chronic kidney disease: A cross-sectional study

OBJECTIVES

The aim of this study was to investigate the association between serum biomarkers and oral health parameters in children with chronic kidney disease (CKD).

MATERIALS AND METHODS

Serum hemoglobin, blood urea nitrogen, serum creatinine, calcium, parathormone, magnesium, and phosphorus levels were measured in 62 children with CKD aged between 4 and 17 years. Intraoral examinations of the patients were performed by two different pediatric dentists. Dental caries was assessed using the decayed-missing-filled-teeth (DMFT/dmft) indexes, and oral hygiene was assessed using the debris (DI), calculus (CI), and simplified oral hygiene (OHI-S) indexes. Spearman's rho coefficient and generalized linear modeling were used to examine the association between serum biomarkers and oral health parameters.

RESULTS

The results of the study showed that there were negative and statistically significant correlations between serum hemoglobin and creatinine levels and dmft scores in pediatric patients with CKD (p = 0.021 and p = 0.019, respectively). Furthermore, blood urea nitrogen levels and DI and OHI-S scores (p = 0.047 and p = 0.050, respectively); serum creatinine levels and DI, CI, and OHI-S scores (p = 0.005, p = 0.047, p = 0.043, respectively); and parathormone levels and CI and OHI-S scores (p = 0.001 and p = 0.017, respectively) were found to be positively and statistically significantly related.

CONCLUSIONS

There are associations between various serum biomarker levels and dental caries and oral hygiene parameters in pediatric patients with CKD.

CLINICAL RELEVANCE

The impact of changes in serum biomarkers on oral and dental health is important for dentists' and medical professionals' approaches to patients' oral and systemic health.

Elemental Compositions of Enamel or Dentin in Human and Bovine Teeth Differ from Murine Teeth

Teeth with different chemical compositions can show vastly different physical properties, so knowledge of elemental composition is required to use animal teeth as substitutes for human teeth in research. In vitro, energy dispersive X-ray spectroscopy (EDX), improved by calibration standards and Si₃N₄-window material, enables determining local elemental compositions of inorganic and organic compounds without sample destruction. Six human molars, bovine incisors, murine incisors, and murine molars were analyzed. EDX-field scans and line scans were analyzed for elements Ca, P, O, C, N, F, Na, Mg, Fe, Cl, and S. Furthermore, Ca/P- and Ca/N-Ratios were calculated. The presence of iron in murine incisor enamel was investigated using additional wavelength dispersive X-ray spectroscopy measurements (WDX) near the enamel surface. Bovine and human enamel and dentin revealed close similarities regarding elemental composition. The median (25-75% percentiles) of At%Ca was 21.1 (20.8-21.3) in human enamel, 21.0 (20.7-21.2) in bovine enamel, and in murine enamel, 18.3 (17.85-18.88) for molars and 18.35 (18.00-18.75) for incisors. In dentin, murine teeth revealed a higher At%Ca compared to human and bovine teeth. Significant differences between human and bovine teeth were found for nitrogen in dentin, with a median of 4.5 (3.3-5) At%N for human dentin and 2.7 (2.3-3.2) At%N for bovine dentin. The Ca/P-Ratio was the highest in human and bovine enamel, which did not differ significantly. Enamel from murine molars had a higher Ca/P-Ratio than murine incisors and the highest Ca/P-Ratio in dentin was observed for human teeth and murine molars (1.49). WDX revealed iron in the outer 10 µm of pre- and post-eruptive enamel of murine incisors. Pre- and post-eruptive enamel on murine incisors only differed significantly in At%Ca (p = 0.041) and At%P (p = 0.026) with both At% higher in the pre-eruptive enamel. Murine teeth differ significantly from human and bovine teeth in terms of the elemental composition of enamel and dentin.

Early Childhood Caries and Iron Deficiency Anaemia: A Systematic Review and Meta-Analysis

Identification of the association between Early Childhood Caries (ECC) and Iron Deficiency Anaemia (IDA) will aid paediatricians and paediatric dentists to enhance health promotion measures to reduce the related morbidity in children. This systematic review aims to determine an evidence-based association between ECC and IDA. A systematic search was carried out from MEDLINE via PubMed, EMBASE, LILACS, Cochrane Oral Health Group's Specialized Register, CINAHL via EBSCO, Web of Science, and Scopus up to May 2020. Hand searching and grey literature screening were also conducted. Cross-sectional, case-control, and cohort studies in English language which assessed the association was included. Two reviewers independently assessed the study quality and extracted the outcome data. A total of 1,434 studies were identified. Fourteen studies qualified for qualitative review and 7 of them for a meta-analysis. In comparison with children not affected by ECC, those affected had an increased likelihood of IDA (OR = 6.07 [3.61, 10.21]). The meta-analysis showed no statistical difference when comparing blood parameters (Hb, MCV, and serum ferritin) in children with and without ECC. This systematic review demonstrates an association between ECC and increased odds of IDA rather than it being the cause for IDA. Further longitudinal studies with robust methodology are required to determine an evidence-based association.

Associations of early childhood caries with salivary beta defensin-3 and childhood anemia: a case-control study

Background

Human beta defensin-3 (HβD-3) is an antimicrobial peptide present in saliva that protects tooth surfaces from microbial attack. These peptides are part of innate immunity so levels may be affected by different systemic diseases like anemia. Therefore, anemia may predispose an affected child to an increased risk of dental caries. The objectives of this study were to determine the association of early childhood caries (ECC) with HβD-3 levels and observe the association of HβD-3 levels with childhood anemia.

Methods

A total of 80 children admitted in a pediatric medical ward, age 48–71 months, of either sex were included in the study. The included children were categorized as cases (children with ECC n = 40) and controls (children without ECC n = 40). Children were further segregated into the anemic and non-anemic sub-groups based on the hospital record of hemoglobin level. The salivary concentration of HβD-3 was measured by Enzyme-Linked Immuno-sorbent assay (ELISA). IBM SPSS version 20 software was used for statistical analysis. Two sample t-test and one-way ANOVA were used to compare mean values while spearman was used for correlations at p < 0.05.

Results

The mean Salivary HβD-3 level in cases (8.87 ± 4.30) was significantly higher (p = 0.042) as compared to controls (7.23 ± 2.57). Salivary HβD-3 level in patients with caries and without anemia was highest (10.80 ± 4.50) whereas salivary HβD-3 level in the presence of caries and anemia was lowest (6.94 ± 3.13) amongst all groups. This difference was statistically significant (p = 0.001). Salivary HβD-3 level was found to be moderately correlated with cases (p = 0.002). An inverse correlation was found between salivary HβD-3 level and anemia (r = -0.479, p = 0.002).

Conclusion

Anemia may affect the innate immunity of children, and may result in a decreased level of salivary HβD3, thus increasing vulnerability to decay.

Iron deficiency anaemia and early childhood caries: a cross-sectional study

BACKGROUND

This study aimed to assess the association between iron deficiency anaemia (IDA) and dental caries in early childhood.

METHODS

A total of 40 children with proven IDA and another 40 healthy age and sex-matched children were enrolled in this cross-sectional study. Legal guardians were interviewed to collect data on oral hygiene measures and dietary habits. Anthropometric measurements were performed for all participants, and blood samples were collected to assess complete blood count and body iron status. Patients were confirmed to have IDA based on haemoglobin level (Hb), red blood cells indices and body iron status. Caries experience was determined based on the number of decayed, missing and filled primary teeth using dmft index.

RESULTS

A statistically significant negative correlation between dmft index scores and haemoglobin level (r = -0.454, P < 0.001) and mean corpuscular haemoglobin (MCH) level (r = -0.380, P = 0.001) was detected, and in accordance there was a positive statistically significant correlation between caries experience and the presence of anaemia (r = -0.60, P < 0.001).

CONCLUSION

In early childhood, dental caries might coexist with IDA even in its mildest form. All children exhibiting severe early childhood caries should be investigated for IDA and anaemia should be managed if present.

Role of Iron on Physical and Mechanical Properties of Brushite Cements, and Interaction with Human Dental Pulp Stem Cells

Improving the physical, mechanical and biological properties of brushite cements (BrC) is of a great interest for using them in bone and dental tissue engineering applications. The objective of this study was to incorporate iron (Fe) at different concentrations (0.25, 0.50, and 1.00 wt.%) to BrC and study the role of Fe on phase composition, setting time, compressive strength, and interaction with human dental pulp stem cells (hDPSCs). Results showed that increase in Fe concentration increases the β-tricalcium phosphate (β-TCP)/ dicalcium phosphate dihydrate (DCPD) ratio and prolongs the initial and final setting time due to effective role of Fe on stabilizing the β-TCP crystal structure and retarding its dissolution kinetic, in a dose dependent manner where the highest setting time was recorded for 1.00 wt.% Fe-BrC sample. Addition of low concentrations of Fe (0.25 and 0.50 wt.%) did not have adverse effect on compressive strength and strength was in the range of 5.7-7.05 (±~1.4) MPa; however, presence of 1.00 wt.% Fe decreases the strength of BrC from 7.05 ± 1.57 MPa to 3.12 ± 1.06 MPa. Interaction between the BrCs and hDPSCs was evaluated by cell proliferation assay, scanning electron microscopy, and live/dead staining. Low concentrations of 0.25, and 0.50 wt.% of Fe did not have any adverse effect on cell attachment and proliferation; while significant decrease in cellular activity was evident in BrC samples doped with 1.00 wt. %. Together, these data show that low concentrations of Fe (equal or less than 0.50 wt. %) can be safely added to BrC without any adverse effect on physical, mechanical and biological properties in presence of hDPSCs.

All You Can Feed: Some Comments on Production of Mouse Diets Used in Biomedical Research with Special Emphasis on Non-Alcoholic Fatty Liver Disease Research

The laboratory mouse is the most common used mammalian research model in biomedical research. Usually these animals are maintained in germ-free, gnotobiotic, or specific-pathogen-free facilities. In these facilities, skilled staff takes care of the animals and scientists usually don’t pay much attention about the formulation and quality of diets the animals receive during normal breeding and keeping. However, mice have specific nutritional requirements that must be met to guarantee their potential to grow, reproduce and to respond to pathogens or diverse environmental stress situations evoked by handling and experimental interventions. Nowadays, mouse diets for research purposes are commercially manufactured in an industrial process, in which the safety of food products is addressed through the analysis and control of all biological and chemical materials used for the different diet formulations. Similar to human food, mouse diets must be prepared under good sanitary conditions and truthfully labeled to provide information of all ingredients. This is mandatory to guarantee reproducibility of animal studies. In this review, we summarize some information on mice research diets and general aspects of mouse nutrition including nutrient requirements of mice, leading manufacturers of diets, origin of nutrient compounds, and processing of feedstuffs for mice including dietary coloring, autoclaving and irradiation. Furthermore, we provide some critical views on the potential pitfalls that might result from faulty comparisons of grain-based diets with purified diets in the research data production resulting from confounding nutritional factors.