Periodontal diseases and adverse pregnancy outcomes: Is there a role for vitamin D?

The association between periodontal disease and adverse pregnancy outcomes: a bibliometric analysis from 2000 to 2023

Background

Periodontal disease (PD) refers to a chronic inflammatory disorder affecting the supporting tissues of the teeth triggered by bacterial infection and is recognized to promote systemic inflammation, leading to dysfunction in specific organs. Adverse pregnancy outcomes (APOs), including preterm birth, small for gestational age infants, gestational diabetes and preeclampsia, are linked to pregnancy complications. Recently, the correlation between periodontal disease and adverse pregnancy outcomes has garnered global attention. However, bibliometric studies in this area remain limited. This study aimed to visualize knowledge framework and research trends concerning the relationship between periodontal disease and adverse pregnancy outcomes from 2000 to 2023 through bibliometric approaches.

Methods

On September 22, 2024, articles and reviews on the connection between periodontal disease and adverse pregnancy outcomes were retrieved from the Web of Science Core Collection (WOSCC). CiteSpace [6.3.R1 (64-bit) Advanced] was used to perform knowledge mapping and bibliometric studies.

Results

Over the past 23 years, 932 articles from 73 countries were collected, with the U.S. contributing over one-third (355), followed by Brazil (85) and India (59). The literature in this field has experienced multiple growth phases since 2000, with particularly rapid growth observed after 2019. The University of North Carolina (n = 34, 3.65%) is the leading institution in terms of publication output, primarily representing the U.S. Notably, the Journal of Periodontology and the American Journal of Obstetrics and Gynecology are the most frequently cited journals in the fields of periodontology and obstetrics, respectively. These publications are authored by 94 researchers, with Steven Offenbacher being both the most productive and most highly cited author, making significant contributions to the field. A visual analysis of keywords identifies "oral microbiota," "oral health," "adverse pregnancy outcomes," and "global burden" as emerging research hotspots in exploring the correlation between periodontal disease and adverse pregnancy outcomes.

Conclusions

This first bibliometric and visual analysis of periodontal disease and adverse pregnancy outcomes offers a concise overview of the field and suggests future research should focus on risk factors, high-risk populations, oral microbiota, mechanisms, interventions, and international collaboration.

Exploring the composition of placental microbiome and its potential origin in preterm birth

Introduction

For years, the placenta was believed to be sterile, but recent studies reveal it hosts a unique microbiome. Despite these findings, significant questions remain about the origins of the placental microbiome and its effects on pregnancy and fetal health. Some studies suggest it may originate from the vaginal tract, while others indicate that oral bacteria can enter the maternal bloodstream and seed the placenta. However, research analyzing the vaginal, oral, and placental microbiomes within the same cohort is lacking. Additionally, it's unclear whether the placental microbiome differs between healthy pregnancies and those with complications like preterm birth (PTB), which remains a leading cause of neonatal morbidity and mortality worldwide.

Methods

In this study, we performed 16S rRNA gene sequencing to investigate the composition of the oral and placental microbiome in samples collected from 18 women who experienced PTB and 36 matched controls who delivered at term (TB), all of whom were part of the Molecular Signature in Pregnancy (MSP) study. We leveraged on the multisite microbiome sampling from the MSP participants and on our previously published vaginal microbiome data to investigate the potential origins of the placental microbiome and assess whether its composition varies between healthy and complicated pregnancies.

Results and Discussion

Our analysis revealed distinct profiles in the oral microbiome of PTB subjects compared to those who delivered at term. Specifically, we observed an increased abundance of Treponema maltophilum, Bacteroides sp, Mollicutes, Prevotella buccae, Leptotrichia, Prevotella_sp_Alloprevotella, in the PTB group. Importantly, Treponema maltophilum species showed higher abundance in the PTB group during the second trimester, suggesting its potential use as biomarkers. When we assessed the placenta microbiome composition, we found that Firmicutes, Bacteroidetes, Actinobacteria, and Proteobacteria were the most dominant phyla. Interestingly, microorganisms such as Ureaplasma urealyticum were more abundant in PTB placenta samples. Our findings suggest that the placenta microbiome could originate from the oral or vaginal cavities, with a notable increase in the crosstalk between the vaginal and placental sites in cases of PTB. Specifically, our data revealed that in PTB cases, the placental microbiome exhibited a closer resemblance to the vaginal microbiome, whereas in term pregnancies, the placental microbiome was similar to the oral microbiome.

Organoids from human tooth showing epithelial stemness phenotype and differentiation potential

Insight into human tooth epithelial stem cells and their biology is sparse. Tissue-derived organoid models typically replicate the tissue’s epithelial stem cell compartment. Here, we developed a first-in-time epithelial organoid model starting from human tooth. Dental follicle (DF) tissue, isolated from unerupted wisdom teeth, efficiently generated epithelial organoids that were long-term expandable. The organoids displayed a tooth epithelial stemness phenotype similar to the DF’s epithelial cell rests of Malassez (ERM), a compartment containing dental epithelial stem cells. Single-cell transcriptomics reinforced this organoid-ERM congruence, and uncovered novel, mouse-mirroring stem cell features. Exposure of the organoids to epidermal growth factor induced transient proliferation and eventual epithelial-mesenchymal transition, highly mimicking events taking place in the ERM in vivo. Moreover, the ERM stemness organoids were able to unfold an ameloblast differentiation process, further enhanced by transforming growth factor-β (TGFβ) and abrogated by TGFβ receptor inhibition, thereby reproducing TGFβ's known key position in amelogenesis. Interestingly, by creating a mesenchymal-epithelial composite organoid (assembloid) model, we demonstrated that the presence of dental mesenchymal cells (i.e. pulp stem cells) triggered ameloblast differentiation in the epithelial stem cells, thus replicating the known importance of mesenchyme-epithelium interaction in tooth development and amelogenesis. Also here, differentiation was abrogated by TGFβ receptor inhibition. Together, we developed novel organoid models empowering the exploration of human tooth epithelial stem cell biology and function as well as their interplay with dental mesenchyme, all at present only poorly defined in humans. Moreover, the new models may pave the way to future tooth-regenerative perspectives.

Association between Maternal Periodontitis and Development of Systematic Diseases in Offspring

Periodontal disease (PD) is one of the most common oral conditions affecting both youths and adults. There are some research works suggesting a high incidence of PD in pregnant women. As an inflammatory disease of bacterial origin, PD may result in the activation of the pathways affecting the course and the pregnancy outcome. The authors, based on the literature review, try to answer the PICO question: Does maternal periodontitis (exposure) influence the incidence of complications rates in pregnancy and the development of systemic diseases in childhood and adult offspring (outcome) in the humans of any race (population) compared to the offspring of mothers with healthy periodontium (comparison)? The authors try to describe the molecular pathways and mechanisms of these interdependencies. There is some evidence that maternal periodontitis may affect the pregnancy course and outcome, resulting in preeclampsia, preterm delivery, vulvovaginitis and low birth weight. It can be suggested that maternal periodontitis may affect offspring epigenome and result in some health consequences in their adult life.

Vitamin D deficiency is a risk factor for delayed tooth eruption associated with persistent primary tooth

OBJECTIVE

To verify the association between 25(OH)D level and polymorphisms in the vitamin D receptor gene (VDR) with the disturbance in the dental development and eruption.

DESIGN

A total of 183 children from two datasets were evaluated. The first dataset was a case-control (15:15) designed to assess if persistent primary tooth (PPT) is associate with serum 25(OH)D level and with genetic polymorphisms in VDR. The second dataset of genomic DNA samples from 54 children with delayed tooth eruption (DTE) and 99 controls were analysed to verify if genetic polymorphisms in VDR (rs2228570 and rs739837) are associated with DTE. The 25(OH)D and the genotyping/allele distribution were analysed using the T-test and chi-square test, respectively.

RESULTS

The level of 25(OH)D in the PPT group (24.9 ± 6.4 mg/mL) was significantly lower than the control (30.0 ± 7.0 mg/mL) (p=.047). Our data show that children with 25(OH)D deficiency are more likely to present PPT (OR = 2.36; 95%CI: 1.51, 3.70). The rs739837 and rs2228570 polymorphisms were not associated with DTE (OR = 1.44; 95%CI: 0.87, 2.39 and OR = 0.80; 95%CI: 0.45, 1.44, respectively).

CONCLUSIONS

Vitamin D deficiency is a risk factor for PPT.

Inflammatory factors, genetic variants, and predisposition for preterm birth

Preterm birth is a major clinical and public health challenge, with a prevalence of 11% worldwide. It is the leading cause of death in children younger than 5 years old and represents 70% of neonatal deaths and 75% of neonatal morbidity. Despite the clinical and public health significance, this condition's etiology is still unclear, and most of the cases are spontaneous. There are several known preterm birth risk factors, including inflammatory diseases and the genetic background, although the underlying molecular mechanisms are far from understood. The present review highlights the research advances on the association between inflammatory-related genes and the increased risk for preterm delivery. The most associated genetic variants are the TNFα rs1800629, the IL1α rs17561, and the IL1RN rs2234663. Moreover, many of the genes discussed in this review are also implicated in pathologies involving inflammatory or autoimmune systems, such as periodontal disease, bowel inflammatory disease, and autoimmune rheumatic diseases. This review presents evidence suggesting a common genetic background to preterm birth, autoimmune and inflammatory diseases susceptibility.

Use of an online medical database for clinical decision-making processes: assessment of knowledge, attitude, and practice of oral health care providers

Purpose: This study was conducted to determine the level of knowledge, attitude, and practice of oral health care providers toward the use of online medical databases for clinical decision-making processes. Subjects and methods: The study population included all the licensed oral health care providers living in Rwanda, registered either with the Rwanda Allied Health Professional Council (RAHPC) or Rwanda Medical and Dental Council (RMDC). A self-administered questionnaire was used to collect demographic data as well as data regarding knowledge, attitude, and practice of oral health care providers regarding the use of online medical databases for making clinical decisions. A pilot study with 12 oral health care providers was done before the main study to pretest the questionnaire. Results: The study results show that among the 201 respondents, 80% (N=160) reported using internet-based resources to support their clinical decisions, while 20% (N=41) of oral health care providers do not use online resources when making their clinical decisions. In general, there was a positive attitude towards internet-based resources among the participants, as 92% (N=184) respondents believe that internet-based resources are helpful in clinical decision-making processes. Of clinical importance, 68% respondents (N=136) believe that by using current internet-based information, better clinical care can be offered to their patients. Conclusion: Educating oral health care providers on the useful and appropriate online resources available for supporting clinical decision-making processes might increase the efficiency of patient care.

Dietary phosphorus enhances inflammatory response: A study of human gingivitis

Phosphates are associated with numerous disorders, ranging from vascular calcification to premature aging, possibly because of an increased inflammatory response. We therefore investigated the association of dietary phosphorus with gingivitis. We analyzed consumption of both phosphorus and sugar and related it to the concentrations of inflammatory biomarkers in saliva samples collected from 8314 children (mean age, 9.99 ± 0.68 years). About 64% of the children consumed more than 1250 mg phosphorus daily, and 34% consumed more than 82 g of sugar daily. Gingivitis was prevalent, with an average of 74% of possible gingival sites considered red. Quantile regression analysis revealed a statistically significant correlation between the occurrence of gingivitis and calorie-adjusted phosphorus intake and between gingivitis and calorie-adjusted sugar intake (both significant either as a linear trend or a categorical variable). In a subset (n = 744) investigation of nutrient consumption related to salivary biomarkers, we found that elevated calorie-adjusted phosphorus intake was directly associated with salivary IL-1β concentration (OR1.40, 95% CI 1.04-1.89), and inversely associated with salivary IL-4 concentration (OR0.62, 95% CI 0.46-0.84). Sugar intake was not significantly associated with either biomarker. Thus, elevated dietary phosphorus consumption may influence inflammatory disease by altering cytokine levels.

Dietary phosphate toxicity: an emerging global health concern

Phosphate is a common ingredient in many healthy foods but, it is also present in foods containing additives and preservatives. When found in foods, phosphate is absorbed in the intestines and filtered from the blood by the kidneys. Generally, any excess is excreted in the urine. In renal pathologies, however, such as chronic kidney disease, a reduced renal ability to excrete phosphate can result in excess accumulation in the body. This accumulation can be a catalyst for widespread damage to the cellular components, bones, and cardiovascular structures. This in turn can reduce mortality. Because of an incomplete understanding of the mechanism for phosphate homeostasis, and the multiple organ systems that can modulate it, treatment strategies designed to minimize phosphate burden are limited. The Recommended Dietary Allowance (RDA) for phosphorous is around 700 mg/day for adults, but the majority of healthy adult individuals consume far more phosphate (almost double) than the RDA. Studies suggest that low-income populations are particularly at risk for dietary phosphate overload because of the higher amounts of phosphate found in inexpensive, processed foods. Education in nutrition, as well as access to inexpensive healthy food options may reduce risks for excess consumption as well as a wide-range of disorders, ranging from cardiovascular diseases to kidney diseases to tumor formation. Pre-clinical and clinical studies suggest that dietary phosphate overload has toxic and prolonged adverse health effects. Improved regulations for reporting of phosphate concentrations on food labels are necessary so that people can make more informed choices about their diets and phosphate consumption. This is especially the case given the lack of treatments available to mitigate the short and long-term effects of dietary phosphate overload-related toxicity. Phosphate toxicity is quickly becoming a global health concern. Without measures in place to reduce dietary phosphate intake, the conditions associated with phosphate toxicity will likely to cause untold damage to the wellbeing of individuals around the world.