Does Pregnancy Have an Impact on the Subgingival Microbiota?

Consideration of hormonal changes for orthodontic treatment during pregnancy and lactation - a review

Hormonal changes in pregnant and lactating women significantly affect bone metabolism and overall stress levels, positioning them as a unique group within the orthodontic population. Fluctuations in estrogen, progesterone, prolactin, and other hormones are closely linked to bone remodeling and the periodontal tissue's response to inflammation caused by dental plaque. Hormones such as thyrotropin, leptin, and melatonin also play crucial roles in pregnancy and bone remodeling, with potential implications for orthodontic tooth movement. Additionally, adverse personal behaviors and changes in dietary habits worsen periodontal conditions and complicate periodontal maintenance during orthodontic treatment. Notably, applying orthodontic force during pregnancy and lactation may trigger stress responses in the endocrine system, altering hormone levels. However, these changes do not appear to adversely affect the mother or fetus. This review comprehensively examines the interaction between hormone levels and orthodontic tooth movement in pregnant and lactating women, offering insights to guide clinical practice.

Subgingival microbial profiles in pre- and postmenopausal women: Associations with serum estradiol levels

BACKGROUND

Subgingival dental plaque is an ecosystem playing a key role in supporting both oral health and systemic health. Menopause-related changes have the potential to disrupt its balance, which is crucial to postmenopausal well-being. Our study explored how circulating estradiol levels correlate with subgingival microbial composition using checkerboard DNA-DNA hybridization in premenopausal and postmenopausal women. We also demonstrated that combining this method with 16S ribosomal RNA (rRNA) sequencing insights remains valuable for examining subgingival ecology.

METHODS

We assessed 40 bacterial species in 77 premenopausal and 81 postmenopausal women using checkerboard DNA-DNA hybridization and measured serum estradiol with enzyme-linked immunosorbent assay (ELISA). Women were categorized by subgingival dysbiosis severity using a modified Subgingival Microbial Dysbiosis Index (mSMDI). Six women from each normobiotic and dysbiotic subgroup across premenopausal and postmenopausal women underwent 16S rRNA sequencing analysis.

RESULTS

DNA checkerboard analysis revealed that most observed variability in individual bacterial proportions is associated with periodontitis. Two species, Leptotrichia buccalis and Streptococcus constellatus, exhibited differences related to estradiol levels within the premenopausal group (p = 0.055 and p = 0.009, respectively). 16S rRNA sequencing confirmed the mSMDI's validity in categorizing normobiotic and dysbiotic states. Menopausal status was not associated with a dysbiotic shift in the subgingival microbiome despite significantly more attachment loss in postmenopausal compared to premenopausal women.

CONCLUSIONS

Our results indicate that decreased estradiol levels or increased attachment loss during menopause are not associated with changes in species abundance or dysbiotic shifts in women. The mSMDI may be a useful tool for classifying subgingival ecology based on its normobiotic or dysbiotic inclination.

Can oral microbiome predict low birth weight infant delivery?

OBJECTIVES

This study aimed to identify the oral microbiota factors contributing to low birth weight (LBW) in Chinese pregnant women and develop a prediction model using machine learning.

METHODS

A nested case-control study was conducted in a prospective cohort of 580 Chinese pregnant women, with 23 LBW cases and 23 healthy delivery controls matched for age and smoking habit. Saliva samples were collected at early and late pregnancy, and microbiome profiles were analyzed through 16S rRNA gene sequencing.

RESULTS

The relative abundance of Streptococcus was over-represented (median 0.259 vs. 0.116) and Saccharibacteria_TM7 was under-represented (median 0.033 vs. 0.068) in the LBW case group than in controls (p < 0.001, p = 0.015 respectively). Ten species were identified as microbiome biomarkers of LBW by LEfSe analysis, which included 7 species within the genus of Streptococcus or as part of 'nutritionally variant streptococci' (NVS), 2 species of opportunistic pathogen Leptotrichia buccalis and Gemella sanguinis (all LDA score>3.5) as risk biomarkers, and one species of Saccharibacteria TM7 as a beneficial biomarker (LDA= -4.5). The machine-learning model based on these 10 distinguished oral microbiota species could predict LBW, with an accuracy of 82 %, sensitivity of 91 %, and specificity of 73 % (AUC-ROC score 0.89, 95 % CI: 0.75-1.0). Results of α-diversity showed that mothers who delivered LBW infants had less stable salivary microbiota construction throughout pregnancy than the control group (measured by Shannon, p = 0.048; and Pielou's, p = 0.021), however the microbiome diversity did not improve the prediction accuracy of LBW.

CONCLUSIONS

A machine-learning oral microbiome model shows promise in predicting low-birth-weight delivery. Even in cases where oral health is not significantly compromised, opportunistic pathogens or rarer taxa associated with adverse pregnancy outcomes can still be identified in the oral cavity.

CLINICAL SIGNIFICANCE

This study highlights the potential complexity of the relationship between oral microbiome and pregnancy outcomes, indicating that mechanisms underlying the association between oral microbiota and adverse pregnancy outcomes may involve complex interactions between host factors, microbiota, and systemic conditions. Using machine learning to develop a predictive model based on specific oral microbiota biomarkers provides a potential for personalized medicine approaches. Future prediction models should incorporate clinical metadata to be clinically useful for improving maternal and child health.

Shaping Microbiota During the First 1000 Days of Life

Given that the host-microbe interaction is shaped by the immune system response, it is important to understand the key immune system-microbiota relationship during the period from conception to the first years of life. The present work summarizes the available evidence concerning human reproductive microbiota, and also, the microbial colonization during early life, focusing on the potential impact on infant development and health outcomes. Furthermore, we conclude that some dietary strategies including specific probiotics and other-biotics could become potentially valuable tools to modulate the maternal-neonatal microbiota during this early critical window of opportunity for targeted health outcomes throughout the entire lifespan.

Clinical, oral immunological and microbiological shifts during and after pregnancy

OBJECTIVES

Physiological changes and shifts in the oral microbiota composition during pregnancy may affect the maternal immune system. Uncomplicated pregnancy is associated with a T-helper (Th) 2 predominant cytokine regulation (anti-inflammatory), while oral health deterioration during pregnancy is reflected by severe gingival inflammation, a primarily Th1 cytokine phenotype (pro-inflammatory), and oral microbiome alterations. This prospective observational study aimed to evaluate Th cytokine shifts and changes in the oral microbiota composition in saliva of women before and after birth.

MATERIAL AND METHODS

Saliva (n = 96) was collected before and 6 months after birth, and medical, oral health, and periodontal status were assessed. In a multiplex immunoassay, 10 cytokines were simultaneously analyzed and cumulative Th1 and Th2 cytokine levels and Th1/Th2 ratio were calculated for all groups. Putative periodontal pathogens (n = 6) were evaluated by quantitative real-time polymerase chain reaction.

RESULTS

Th2 cytokine levels were significantly lower (p = 0.014) while pro-inflammatory cytokine levels were significantly higher (p < 0.01) during pregnancy than postpartum. Similar Th1 levels were found between the groups (p = 0.143). Th1 and Th2 cytokines positively correlated with periodontal parameters (p < 0.001) and levels of studied bacteria during pregnancy (p < 0.05).

CONCLUSIONS

This study identified a significantly increased Th1/Th2 cytokine ratio during pregnancy and a positive association with putative periodontal pathogens. This immunological and microbiological deregulation in the oral milieu during pregnancy is suggestive of a destructive inflammatory periodontal profile.

STUDY REGISTRATION

Clinical Trials.gov (Record BAP-2015).

CLINICAL RELEVANCE

Understanding altered oral immunological and microbiological regulation patterns during pregnancy may help improve the inflammatory periodontal profile in pregnant women.

A Randomized Controlled Clinical Trial of Prenatal Oral Hygiene Education in Pregnancy-Associated Gingivitis

INTRODUCTION

Research shows there is a significant increase in gingival inflammation during pregnancy. This study was conducted to determine if an oral health intervention (OHI), including oral hygiene education delivered by nurse-led staff and an advanced over-the-counter (OTC) oral home care regimen, improved gingival inflammation in pregnant women with moderate-to-severe gingivitis compared with a standard oral hygiene control group.

METHODS

This was a multicenter, randomized, controlled, single-masked, parallel group clinical trial conducted in obstetrics clinics of 2 medical centers. A total of 750 pregnant women between 8 and 24 weeks of pregnancy with at least 20 natural teeth and moderate-to-severe gingivitis (>30 intraoral bleeding sites) were enrolled. Participants were randomized to either the OHI group, which included oral hygiene instructions supplemented with an educational video and advanced OTC antibacterial/mechanical oral hygiene products, or the control group receiving oral hygiene instructions and standard products. Both groups received oral hygiene instructions from nurse-led staff. Experienced, masked examiners measured whole mouth gingival index (GI) and periodontal probing depths (PDs) at baseline and months 1, 2, and 3.

RESULTS

Participants enrolled in this study presented with moderate-to-severe gingivitis at baseline. Both the OHI and control groups exhibited significant reductions in GI (P < .001) and PD (P < .03) from baseline that persisted throughout the study period. The OHI group exhibited modest, yet statistically greater, reductions in GI (P ≤ .044) compared with the control at all time points. The reduction in PD directionally favored the OHI group, but between-group differences were small (<0.03 mm) and not statistically significant (P > .18).

DISCUSSION

Significant gingivitis was prevalent among participants in this study and identifies an opportunity to improve gingival health during pregnancy by providing oral health education during the course of prenatal care when coupled with an advanced OTC oral hygiene regimen.

Smoking-induced subgingival dysbiosis precedes clinical signs of periodontal disease

Smoking accelerates periodontal disease and alters the subgingival microbiome. However, the relationship between smoking-associated subgingival dysbiosis and progression of periodontal disease is not well understood. Here, we sampled 233 subgingival sites longitudinally from 8 smokers and 9 non-smokers over 6-12 months, analyzing 804 subgingival plaque samples using 16 rRNA sequencing. At equal probing depths, the microbial richness and diversity of the subgingival microbiome was higher in smokers compared to non-smokers, but these differences decreased as probing depths increased. The overall subgingival microbiome of smokers differed significantly from non-smokers at equal probing depths, which was characterized by colonization of novel minority microbes and a shift in abundant members of the microbiome to resemble periodontally diseased communities enriched with pathogenic bacteria. Temporal analysis showed that microbiome in shallow sites were less stable than deeper sites, but temporal stability of the microbiome was not significantly affected by smoking status or scaling and root planing. We identified 7 taxa-Olsenella sp., Streptococcus cristatus, Streptococcus pneumoniae, Streptococcus parasanguinis, Prevotella sp., Alloprevotella sp., and a Bacteroidales sp. that were significantly associated with progression of periodontal disease. Taken together, these results suggest that subgingival dysbiosis in smokers precedes clinical signs of periodontal disease, and support the hypothesis that smoking accelerates subgingival dysbiosis to facilitate periodontal disease progression.

The Nasal Bacteria Microbiome Comparison Among Fungal Ball Sinusitis, Chronic Sinusitis with Polyps

To evaluate the composition of the microbial community of the middle nasal in paranasal sinus fungus ball (FB), chronic sinusitis with nasal polyps (CRSwNP) and healthy controls, providing new insights into the pathogenesis of FB and CRSwNP. Through 16 s rRNA gene high-throughput sequencing to determine the microbial characterization from patients with FB (n = 29) and CRSwNP (n = 10), and healthy controls (n = 4). The FB group had significantly lower αdiversity and significantly different β diversity compared to the other groups. All three groups mainly consisted of four bacterial phyla (Firmicutes, Proteobacteria, Bacteroidetes, Actinobacteria). In the FB group, the highest relative abundance was found in Proteobacteria (47.04%). However, pairwise comparisons resulted in statistically significant differences only for Firmicutes (CRSwNP, p = 0.003, Control, p = 0.008). The CRSwNP group was statistically different from the control group in TM7(p = 0.010), Chloroflexi(p = 0.018) and Bacteroidete(p = 0.027). At the genus level, the FB group had the highest relative abundance of Haemophilus (11.53%), followed by Neisseria (7.39%), and Neisseria abundance (p < 0.001) was significantly different from the remaining two groups. Ruminococcacea abundance (p < 0.001) and Comamonadaceae abundance (p < 0.001) were increased in the CRSwNP group. The relative abundance of Lactobacillus (p < 0.001), Bacteroides S24_7 (p < 0.001), and Desulfovibrio (p < 0.001) was significantly decreased in the FB and CRSwNP groups compared to the control group. The imbalance of the microbial community is related to the pathogenesis of sinusitis.

Subgingival Microbiome in Pregnancy and a Potential Relationship to Early Term Birth

Background

Periodontal disease in pregnancy is considered a risk factor for adverse birth outcomes. Periodontal disease has a microbial etiology, however, the current state of knowledge about the subgingival microbiome in pregnancy is not well understood.

Objective

To characterize the structure and diversity of the subgingival microbiome in early and late pregnancy and explore relationships between the subgingival microbiome and preterm birth among pregnant Black women.

Methods

This longitudinal descriptive study used 16S rRNA sequencing to profile the subgingival microbiome of 59 Black women and describe microbial ecology using alpha and beta diversity metrics. We also compared microbiome features across early (8-14 weeks) and late (24-30 weeks) gestation overall and according to gestational age at birth outcomes (spontaneous preterm, spontaneous early term, full term).

Results

In this sample of Black pregnant women, the top twenty bacterial taxa represented in the subgingival microbiome included a spectrum representative of various stages of biofilm progression leading to periodontal disease, including known periopathogens Porphyromonas gingivalis and Tannerella forsythia. Other organisms associated with periodontal disease reflected in the subgingival microbiome included several Prevotella spp., and Campylobacter spp. Measures of alpha or beta diversity did not distinguish the subgingival microbiome of women according to early/late gestation or full term/spontaneous preterm birth; however, alpha diversity differences in late pregnancy between women who spontaneously delivered early term and women who delivered full term were identified. Several taxa were also identified as being differentially abundant according to early/late gestation, and full term/spontaneous early term births.

Conclusions

Although the composition of the subgingival microbiome is shifted toward complexes associated with periodontal disease, the diversity of the microbiome remains stable throughout pregnancy. Several taxa were identified as being associated with spontaneous early term birth. Two, in particular, are promising targets of further investigation. Depletion of the oral commensal Lautropia mirabilis in early pregnancy and elevated levels of Prevotella melaninogenica in late pregnancy were both associated with spontaneous early term birth.

Identification of the specific microbial community compositions in saliva associated with periodontitis during pregnancy

OBJECTIVE

To identify the specific microbial community compositions in saliva associated with periodontitis during pregnancy.

MATERIALS AND METHODS

Unstimulated saliva samples were collected from 53 pregnant women during weeks 24-28 of gestation, and the V3-V4 regions of the 16S rRNA gene were amplified from isolated saliva DNA and sequenced. Phylum-, genus-, and species-level taxonomic compositions were separately compared between subjects with (n = 12) and without (n = 41) periodontitis.

RESULTS

Taxa were selected using the random forest algorithm to distinguish subjects with periodontitis at each taxonomic level, and principal component biplots were constructed to visualize the composition of selected taxa in each subject. The genus-level biplot indicated that 44 subjects clustered around the origin. The prevalence of periodontitis was significantly higher among subjects outside the cluster compared with subjects inside the cluster (6/9 [67%] vs. 6/44 [14%], respectively; p = 0.002). Subjects outside the cluster also had significantly decreased abundance of Neisseria and increased abundances of several putative periodontopathic genera. Phylum- and species-level biplots failed to discriminate subjects with periodontitis more efficiently than the genus-level biplot.

CONCLUSIONS

The specific taxonomic composition of the saliva microbiota in pregnant women with periodontitis could be clearly identified at the genus level.

CLINICAL RELEVANCE

The formula developed based on the present findings, (%Treponema + %Tannerella + %Filifactor + %Anaeroglobus)/%Neisseria, can be used to predict periodontitis during pregnancy with sensitivity and specificity values of 0.67 (8/12) and 0.95 (39/41), respectively.

Periodontology and pregnancy: An overview of biomedical and epidemiological evidence

Women are particularly susceptible to developing gingival problems during pregnancy. In addition, periodontal disease in pregnant women may lead to adverse outcomes for both mother and infant, which have serious clinical and public health implications. Both scenarios have been extensively researched, helping to bring attention to pregnant women as an important and vulnerable population as it concerns periodontal health. The increase in gingival inflammation caused by hormonal changes in pregnant women is undisputed and has been studied and documented since the 1960s, although the exact etiology is not fully understood. The relationship between periodontal disease during pregnancy and adverse pregnancy outcomes is less substantiated, because of conflicting evidence. This review of the biomedical and epidemiologic literature provides an overview of both sides of this relationship and examines the potential mechanisms for developing periodontal disease during pregnancy and the proposed mechanisms by which periodontal disease leads to adverse pregnancy outcomes.

Oral microflora and pregnancy: a systematic review and meta-analysis

Understanding changes in oral flora during pregnancy, its association to maternal health, and its implications to birth outcomes is essential. We searched PubMed, Embase, Web of Science, and Cochrane Library in May 2020 (updated search in April and June 2021), and conducted a systematic review and meta-analyses to assess the followings: (1) oral microflora changes throughout pregnancy, (2) association between oral microorganisms during pregnancy and maternal oral/systemic conditions, and (3) implications of oral microorganisms during pregnancy on birth outcomes. From 3983 records, 78 studies were included for qualitative assessment, and 13 studies were included in meta-analysis. The oral microflora remains relatively stable during pregnancy; however, pregnancy was associated with distinct composition/abundance of oral microorganisms when compared to postpartum/non-pregnant status. Oral microflora during pregnancy appears to be influenced by oral and systemic conditions (e.g. gestational diabetes mellitus, pre-eclampsia, etc.). Prenatal dental care reduced the carriage of oral pathogens (e.g. Streptococcus mutans). The Porphyromonas gingivalis in subgingival plaque was more abundant in women with preterm birth. Given the results from meta-analyses were inconclusive since limited studies reported outcomes on the same measuring scale, more future studies are needed to elucidate the association between pregnancy oral microbiota and maternal oral/systemic health and birth outcomes.

Pregnancy and Dentistry: A Literature Review on Risk Management during Dental Surgical Procedures

Background: Pregnancy is a unique moment in a woman’s life, accompanied with several physiologic changes that have an impact on oral health. Aim of the study: The purpose of the present study was to conduct a critical review of published literature regarding pregnancy and dentistry, the most frequent oral diseases that are encountered during pregnancy, their correlation to adverse pregnancy events, and safe dental treatments that can be performed during pregnancy. Methods: A Medline/COCHRANE search was carried using specific keywords and MeSH terms, combined with the boolean operators “OR” and “AND”. Results: The search led to 146 publications including guidelines, meta-analyses, systematic and non-systematic reviews, published between 2000 and 2021. Discussion and conclusions: Due to the increased inflammatory and immune body response that characterizes pregnancy, periodontal conditions are often aggravated during pregnancy and periodontal disease encountered frequently in pregnant patients. There are conflicting study results in the literature regarding the association between periodontitis and adverse pregnancy outcomes. Periodontal treatment did not show a significant reduction in the adverse outcomes. Many dentists, often due to lack of information, are reluctant to provide dental treatment to pregnant women. However, preventive and restorative dental treatment is safe during pregnancy. Diagnostic radiographs may be performed after the first trimester if absolutely necessary. Analgesics (such as paracetamol) and anesthetics (such as lidocaine) are also considered safe. In case of infection, antibacterial drugs such as amoxicillin, ampicillin, and some cephalosporines and macrolides can also be prescribed. Organogenesis takes place in the first trimester, the time during which the fetus is susceptible to severe malformations (teratogenesis). The ideal time to perform dental treatment is the second trimester (week 17 to 28). However, acute pain or infections make the intervention of the dentist absolutely necessary and emergency treatment can be performed during the whole pregnancy period.

Unculturable and culturable periodontal-related bacteria are associated with periodontal inflammation during pregnancy and with preterm low birth weight delivery

Recent studies revealed culturable periodontal keystone pathogens are associated with preterm low birth weight (PLBW). However, the oral microbiome is also comprised of hundreds of 'culture-difficult' or 'not-yet-culturable' bacterial species. To explore the potential role of unculturable and culturable periodontitis-related bacteria in preterm low birth weight (PLBW) delivery, we recruited 90 pregnant women in this prospective study. Periodontal parameters, including pocket probing depth, bleeding on probing, and clinical attachment level were recorded during the second trimester and following interviews on oral hygiene and lifestyle habits. Saliva and serum samples were also collected. After delivery, birth results were recorded. Real-time PCR analyses were performed to quantify the levels of periodontitis-related unculturable bacteria (Eubacterium saphenum, Fretibacterium sp. human oral taxon(HOT) 360, TM7 sp. HOT 356, and Rothia dentocariosa), and cultivable bacteria (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Fusobacterium nucleatum and Prevotella intermedia) in saliva samples. In addition, ELISA analyses were used to determine the IgG titres against periodontal pathogens in serum samples. Subjects were categorized into a Healthy group (H, n = 20) and periodontitis/gingivitis group (PG, n = 70) according to their periodontal status. The brushing duration was significantly lower in the PG group compared to the H group. Twenty-two of 90 subjects delivered PLBW infants. There was no significant difference in periodontal parameters and serum IgG levels for periodontal pathogens between PLBW and healthy delivery (HD) groups. However, ordinal logistic regression analysis revealed that a higher abundance of Treponema denticola, Prevotella intermedia, Fretibacterium sp. HOT360 and lower levels of Rothia dentocariosa were significantly associated with the presence of periodontal disease during pregnancy. Moreover, the amount of Eubacterium saphenum in saliva and serum IgG against Aggregatibacter actinomycetemcomitans were negatively correlated with PLBW. Taken together, unculturable periodontitis-associated bacteria may play an important role both in the presence of periodontal inflammation during pregnancy and subsequent PLBW.

Periodontopathogenic microbiota, infectious mechanisms and preterm birth: analysis with structural equations (cohort-BRISA)

PURPOSE

The association between periodontopathogenic microbiota and preterm birth (PTB) has been overly studied. However, the biological mechanisms involved are little known. The objective is to evaluate the effect of periodontopathogenic bacteria burden (PBB), periodontal disease and other infections during pregnancy on preterm birth (PTB), through Structural Equation Modeling.

METHODS

This was a case-control study nested in a prospective cohort called BRISA, including 330 pregnant women, 110 cases and 220 controls. This study included the following variables: cytokines interleukin-10 (IL-10) and transforming growth factor beta (TGF-β), periodontal disease, PBB, age, socioeconomic status (SES), systemic infections and PTB. The correlations between variables were analyzed using Standardized Coefficient (SC).

RESULTS

Greater PBB interfered positively with the occurrence of periodontal disease (SC: 0.027; p: 0.011), but these were not associated with the cytokines studied, nor with PTB. The lower serum levels of IL-10 (SC - 0.330; p 0.022) and TGF-β (SC - 0.612; p  < 0.001), and the presence of other systemic infections during pregnancy (SC 0.159; 0.049) explained the higher occurrence of PTB.

CONCLUSION

It is possible that only the more severe periodontal disease and other systemic infections are capable of altering the cascade of cytokines regulating the inflammatory process and have an effect on the occurrence of PTB.

Correlation of periodontal and microbiological evaluations, with serum levels of estradiol and progesterone, during different trimesters of gestation

Our purpouse was to identify quantitatively and qualitatively the subgingival flora in different gestational trimesters, compared to non-pregnant women; evaluating the correlations between epidemiological characteristics, clinical diagnosis, microbiological findings and levels of estradiol and progesterone. 52 pregnant women divided into 3 groups, according to the gestational trimester and 15 non-pregnant patients, without hormonal contraceptives, were evaluated. Plaque index (PI), gingival index (GI), probing depth (PD) and clinical attachment level (CAL) were evaluated. Subgingival biofilm samples were processed by the qPCR technique and the serum levels of estradiol and progesterone quantified by chemiluminescence. Clinical diagnosis during gestation was correlated with the total bacterial count. A higher prevalence of Tannerella forsythia (Tf) was identified in first trimester of pregnancy and this periodontopathogen was correlated with the diagnosis of gingivitis among pregnant women. Porphyromonas gingivalis (Pg) showed a positive correlation with progesterone levels in the first trimester. High prevalence of periodontopathogens was noticed in this population. Clinical diagnosis in gestation was positively correlated with the total amount of bacteria, without influence of the hormonal levels or the epidemiological factors evaluated. The presence of Tf favored occurrence of gingivitis during pregnancy and the progesterone levels in the first trimester enhanced the growth of Pg.

The oral microbiota - a mechanistic role for systemic diseases

Human oral microbiota is the ecological community of commensal, symbiotic, and pathogenic microorganisms found in the oral cavity. Oral microbiota generally exists in the form of a biofilm and plays a crucial role in maintaining oral homeostasis, protecting the oral cavity and preventing disease development. Human oral microbiota has recently become a new focus research for promoting the progress of disease diagnosis, assisting disease treatment, and developing personalised medicines. In this review, the scientific evidence supporting the association that endogenous and exogenous factors (diet, smoking, drinking, socioeconomic status, antibiotics use and pregnancy) modulate oral microbiota. It provides insights into the mechanistic role in which oral microbiota may influence systemic diseases, and summarises the challenges of clinical diagnosis and treatment based on the microbial community information. It provides information for noninvasive diagnosis and helps develop a new paradigm of personalised medicine. All these benefit human health in the post-metagenomics era.

Shaping Microbiota During the First 1000 Days of Life

The data obtained in prior studies suggest that early microbial exposition begins prior to conception and gestation. Given that the host-microbe interaction is shaped by the immune system response, it is important to understand the key immune system-microbiota relationship during the period from conception to the first years of life. The present work summarizes the available evidence concerning early microbiota exposure within the male and the female reproductive tracts at the point of conception and during gestation, focusing on the potential impact on infant development during the first 1000 days of life. Furthermore, we conclude that some dietary strategies including specific probiotics could become potentially valuable tools to modulate the gut microbiota during this early critical window of opportunity for targeted health outcomes throughout the entire lifespan.

Characterizing the Subgingival Microbiome of Pregnant African American Women

OBJECTIVE

To generate preliminary data about the subgingival microbiome of pregnant African American women to calculate power for a future larger study and to explore associations among the microbiome, periodontal inflammation, and preterm birth.

DESIGN

Comparative descriptive pilot study design.

SETTING

Urban area in the southeastern United States.

PARTICIPANTS

Thirty-four African American women in the third trimester of pregnancy.

METHODS

Based on visual assessment, participants were placed in two groups: healthy gingiva and gingivitis. Saliva samples were analyzed for interleukin-1β (IL-1β), matrix metalloproteinase-8 (MMP-8), and C-reactive protein (CRP). DNA was extracted from subgingival plaque samples, and amplicons of the fourth hypervariable region were sequenced.

RESULTS

We found no differences in overall microbiome diversity between the healthy gingiva (n = 22) and the gingivitis (n = 12) groups although significant differences were found among the bacterial taxa present. The gingivitis group had greater levels of salivary IL-1β and MMP-8, whereas CRP was not different between groups. Overall microbiome diversity was positively associated with the CRP level. We found no significant relationships among the subgingival microbiome, periodontal inflammation, and preterm birth.

CONCLUSION

Gingivitis in pregnancy did not appear to shift the overall composition or diversity of the subgingival microbiome although differences in several bacterial taxa suggest that inflamed gingiva in pregnant women are associated with a disruption in the stability of the subgingival microbiome. A correlation between the abundance of bacteria and CRP also suggests an association between the microbiome and systemic inflammation. These findings provide support for future research about how the oral microbiome and progression of periodontal disease in pregnant women link with adverse pregnancy outcomes.

Association between periodontitis and spontaneous abortion: A case-control study

BACKGROUND

Spontaneous abortion, or miscarriage, is a complication of pregnancy which can severely affect women both physically and psychologically. We investigated the associations of periodontitis and periodontopathic bacteria with spontaneous abortion.

METHODS

We conducted a matched case-control study in two tertiary hospitals in Khon Kaen, Thailand. Cases were 85 women with spontaneous abortion at <20 weeks of gestation matched to 85 controls on age, gestational age, and hospital. Full-mouth periodontal examinations were performed. Periodontitis was defined as at least one site with probing depth ≥5 mm and clinical attachment level ≥2 mm at the same site. Subgingival plaque samples were collected to determine the levels of Porphyromonas gingivalis, Tannerella forsythia, and Fusobacterium nucleatum using real time polymerase chain reaction.

RESULTS

The cases were significantly more likely to have periodontitis (50.6%) than the controls (21.2%; P = 0.007). Conditional logistic regression revealed a crude odds ratio (OR) of 4.1 for the association between periodontitis and spontaneous abortion (95% confidence interval [CI] = 1.9-8.9, P = 0.001). The OR decreased, but was still significant, after controlling for previous miscarriage (OR = 3.3, 95% CI = 1.4-7.8, P = 0.006). There was no significant association between the levels of periodontopathic bacteria and spontaneous abortion. Increased levels of P. gingivalis and F. nucleatum were associated with periodontitis in both case and control groups. Association between increased T. forsythia levels and periodontitis was observed only in the case women.

CONCLUSIONS

Periodontitis was more common in women with spontaneous abortions as compared with matched controls. Levels of periodontopathic bacteria was not associated with spontaneous abortion in this population.

Keystone Species in Pregnancy Gingivitis: A Snapshot of Oral Microbiome During Pregnancy and Postpartum Period

It is well known that pregnancy is under the constant influence of hormonal, metabolic and immunological factors and this may impact the oral microbiota toward pregnancy gingivitis. However, it is still not clear how the oral microbial dysbiosis can modulate oral diseases as oral microbiome during pregnancy is very poorly characterized. In addition, the recent revelation that placental microbiome is akin to oral microbiome further potentiates the importance of oral dysbiosis in adverse pregnancy outcomes. Hence, leveraging on the 16S rRNA gene sequencing technology, we present a snapshot of the variations in the oral microbial composition with the progression of pregnancy and in the postpartum period and its association with pregnancy gingivitis. Despite the stability of oral microbial diversity during pregnancy and postpartum period, we observed that the microbiome makes a pathogenic shift during pregnancy and reverts back to a healthy microbiome during the postpartum period. Co-occurrence network analysis provided a mechanistic explanation of the pathogenicity of the microbiome during pregnancy and predicted taxa at hubs of interaction. Targeting the taxa which form the ecological guilds in the underlying microbiome would help to modulate the microbial pathogenicity during pregnancy, thereby alleviating risk for oral diseases and adverse pregnancy outcomes. Our study has also uncovered the possibility of novel species in subgingival plaque and saliva as the key players in the causation of pregnancy gingivitis. The keystone species hold the potential to open up avenues for designing microbiome modulation strategies to improve host health during pregnancy.

Porphyromonas gingivalis induces exacerbated periodontal disease during pregnancy

Although pregnant women are prone to gingival inflammation, its mechanism remains unclear. Animal models are ideal for investigating immunological mechanisms in the periodontal disease. A murine model for ligature-induced periodontal disease has been modified and utilized to determine the susceptibility to periodontal inflammation and tissue damage in pregnant mice. Expression of different inflammatory mediators in the gingivae was determined by quantitative real-time PCR (qPCR). Inflammatory bone loss was determined by measuring the distance from the cementoenamel junction to the alveolar bone crest (CEJ-ABC). Oral bacterial number was determined by the CFU (Colony Forming Units) count from anaerobic culture of oral swabs. In our experiments, ligation itself did not cause higher gingival inflammation and bone loss in pregnant mice than non-pregnant mice, while ligation combined with P. gingivalis infection led to increased gingival inflammation and periodontal bone loss, accompanied by lower gingival expression of anti-inflammatory cytokines in pregnant mice. Our results indicated that P. gingivalis infection was important in inducing more severe periodontal diseases during pregnancy, which might be attributed to the down-regulated anti-inflammatory mechanisms, but not be associated with higher oral bacterial burden.

Pregnancy-induced periodontal inflammation: Influence of salivary cytokines and antimicrobial proteins

The aim of this study was to evaluate the association between pregnancy-induced periodontal inflammation and levels of some salivary cytokines and antimicrobial proteins (AMPs). The study was a cohort longitudinal study that included pregnant women attending a secondary health facility. Consented participants had oral examination and saliva sampling during pregnancy and post-partum (three months after pregnancy). Saliva samples were used for the analysis of cytokines (TNF-α, IFN-gamma and IL-1β) and AMPs (Lactoferin, Lysozyme, and β defensin-1) using ELISA. Data are presented as median with interquartile range and compared using related sample Wilcoxon signed rank test. Correlations between levels of the salivary factors and indices of periodontal inflammation were determined using Spearman’s correlation test. Salivary flow rate, pH, levels of salivary IL-1β and IFN-gamma were significantly lower; while gingival index, periodontal index and level of salivary TNF-α were significantly higher during pregnancy compared with postpartum period. However, salivary lactoferin, lysozyme and β defensin-1 did not show significant difference comparing during pregnancy and postpartum period. Level of salivary IFN-gamma showed negative correlation with gingival index while level of salivary TNF-α showed positive correlation with gingival and periodontal indices. Lower levels of salivary IL-1β and IFN-gamma along with higher TNF-α concentration during pregnancy suggest their contributions to the pathophysiology of pregnancy-induced periodontal inflammation.

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

Studies have shown a relationship between maternal periodontal diseases (PDs) and premature delivery. PDs are commonly encountered oral diseases which cause progressive damage to the periodontal ligament and alveolar bones, leading to loss of teeth and oral disabilities. PDs also adversely affect general health by worsening of cardiovascular and metabolic diseases. Moreover, maternal PDs are thought to be related to increasing the frequency of preterm-birth with low birth weight (PBLBW) in new-borns. Prematurity and immaturity are the leading causes of prenatal and infant mortality and is a major public health problem around the world. Inflamed periodontal tissues generate significantly high levels of proinflammatory cytokines that may have systemic effects on the host mother and the fetus. In addition, the bacteria that cause PDs produce endotoxins which can harm the fetus. Furthermore, studies have shown that microorganisms causing PDs can get access to the bloodstream, invading uterine tissues, to induce PBLBW. Another likely mechanism that connects PDs with adverse pregnancy outcome is maternal vitamin D status. A role of inadequate vitamin D status in the genesis of PDs has been reported. Administration of vitamin D supplementation during pregnancy could reduce the risk of maternal infections and adverse pregnancy outcomes. As maternal PDs are significant risk factors for adverse pregnancy outcome, preventive antenatal care for pregnant women in collaboration with the obstetric and dental professions are required.

[The Microbiome - The Unscheduled Parameter for Future Therapies]

The microbiome is defined as the total of cellular microorganisms of baczerial, viral or e. g., parasite origin living on the surface of a body. Within the anatomical areas of otorhinolaryngology, a significant divergence and variance can be demonstrated. For ear, nose, throat, larynx and cutis different interactions of microbiome and common factors like age, diet and live style factors (e. g., smoking) have been detected in recent years. Besides, new insights hint at a passible pathognomic role of the microbiome towards diseases in the ENT area. This review article resumes the present findings of this rapidly devloping scientific area.

Pregnancy and periodontal disease: does exist a two-way relationship?

Periodontal disease (PD) is an inflammatory disease of the tissues supporting the teeth. PD affects 65 million adults over the age of 30 years in the USA, and worldwide 5 to 70% of adults. Women who develop PD during pregnancy, it's estimated 1 woman in 5, may have a higher risk of adverse pregnancy outcomes. PD during pregnancy starts by dental plaque and is increased by the action of pregnancy hormones. In order to study the effect of PD on adverse pregnancy outcomes, we have performed this narrative review summarising the current studies about the influence of PD on pregnancy. Periodontal pockets are a reservoir of oral microbiota. Modifications in oral microbiota may be considered as a potential mechanism for developing PD during pregnancy. PD is surely caused by bacteria, but the progression and worsening are due to a host immune response. The inflammation caused by PD is not limited to the oral cavity. It is hypothesized that episodes of bacteraemia and dissemination of endotoxins from periodontal pockets can induce the activation of the systemic immune response. In conclusion our narrative review shows that there's no relationship between PD and adverse pregnancy outcomes, and PD treatment during pregnancy does not confer a general protection against adverse pregnancy outcomes.

Leptotrichia species in human infections II

Leptotrichia species are non-motile facultative anaerobic/anaerobic bacteria that are found mostly in the oral cavity and some other parts of the human body, in animals, and even in ocean sediments. Valid species include L. buccalis, L. goodfellowii, L. hofstadii, L. honkongensis, L. shahii, L. trevisanii, and L. wadei. Some species require serum or blood for growth. All species ferment carbohydrates and produce lactic acid that may be involved with tooth decay. Acting as opportunistic pathogens, they are involved in a variety of diseases, and have been isolated from immunocompromised but also immunocompetent individuals. Mucositis, oral lesions, wounds, and abscesses may predispose to Leptotrichia septicemia. Because identification of Leptotrichia species by phenotypic features occasionally lead to misidentification, genetic techniques such as 16S rRNA gene sequencing is recommended. Early diagnosis and treatment of leptotrichia infections is important for positive outcomes. Over the last years, Leptotrichia species have been associated with several changes in taxonomy and new associations with clinical diseases. Such changes are reported in this updated review.

Porphyromonas gingivalis and adverse pregnancy outcome

Porphyromonas gingivalis is a Gram-negative, anaerobic bacterium considered to be an important pathogen of periodontal disease that is also implicated in adverse pregnancy outcome (APO). Until recently, our understanding of the role of P. gingivalis in APO has been limited and sometimes contradictory. The purpose of this review is to provide an overview of past and current research on P. gingivalis that addresses some of the controversies concerning the role of this organism in the pathogenesis of APO.

The effect of dental health education on pregnant women's adherence with toothbrushing and flossing - A randomized control trial

OBJECTIVES

In a three-arm randomized control trial, this study compared the efficacy of dental health education (DHE) with or without a planning intervention on adherence to oral health-related behaviours.

METHODS

Women (N=154) in their second trimester of pregnancy attending three maternal healthcare clinics in Kuwait completed an assessment of social cognitions and oral health behaviours before a debris and gingival assessment (Plaque Index [PI], Gingival Index [GI]) was undertaken; this was repeated at 1 month. In addition to treatment as usual (TAU), which was a demonstration of OH practices, intervention participants received one of two interventions: (i) DHE, which targeted social cognitions; or (ii) DHE and planning (DHE&P), which targeted social cognitions and intentions to undertake oral health behaviours. The TAU group was given a standard oral hygiene leaflet.

RESULTS

At Time one (T1) 154 women were eligible and randomly allocated to the three groups, respectively: treatment as usual (TAU)=53; DHE=53; DHE and planning=48. At Time two (T2), the number of women in each group completing the intervention (N=90) was, respectively, as follows TAU=28; DHE=30; DHE&P=32. There were no demographic differences between the groups at baseline. The mean age of women was 27.80±SD 5.40; 43% (n=38) had a high school level education. A mixed factor ANOVA analysis demonstrated that all women improved their PI (F=94.343 df=1 P=.001) and GI (F=73.138 df=1 P=.001) scores. There were no differences in self-reported oral hygiene and PI and GI by intervention group. The social cognition models (SCM) constructs changed over time in all women (N=90) except barriers to attendance (F=1.067 df=1 P=.305). There were no statistically significant differences in SCM constructs by intervention group at T2. All women reported increasing the frequency of toothbrushing and flossing.

CONCLUSIONS

The provision of information using a simple leaflet improved the adherence of Kuwaiti pregnant with toothbrushing and flossing advice, while the addition of DHE targeting social cognitions and planning conferred no additional benefits.

Perinatal Mortality Associated with Positive Postmortem Cultures for Common Oral Flora

Introduction. To investigate whether maternal oral flora might be involved in intrauterine infection and subsequent stillbirth or neonatal death and could therefore be detected in fetal and neonatal postmortem bacterial cultures. Methods. This retrospective study of postmortem examinations from 1/1/2000 to 12/31/2010 was searched for bacterial cultures positive for common oral flora from heart blood or lung tissue. Maternal age, gestational age, age at neonatal death, and placental and fetal/neonatal histopathological findings were collected. Results. During the study period 1197 postmortem examinations (861 stillbirths and 336 neonatal deaths) were performed in our hospital with gestational ages ranging from 13 to 40+ weeks. Cultures positive for oral flora were identified in 24 autopsies including 20 pure and 8 mixed growths (26/227, 11.5%), found in 16 stillbirths and 8 neonates. Microscopic examinations of these 16 stillbirths revealed 8 with features of infection and inflammation in fetus and placenta. The 7 neonatal deaths within 72 hours after birth grew 6 pure isolates and 1 mixed, and 6 correlated with fetal and placental inflammation. Conclusions. Pure isolates of oral flora with histological evidence of inflammation/infection in the placenta and fetus or infant suggest a strong association between maternal periodontal conditions and perinatal death.

Distinguishing the Signals of Gingivitis and Periodontitis in Supragingival Plaque: a Cross-Sectional Cohort Study in Malawi

Periodontal disease ranges from gingival inflammation (gingivitis) to the inflammation and loss of tooth-supporting tissues (periodontitis). Previous research has focused mainly on subgingival plaque, but supragingival plaque composition is also known to be associated with disease. Quantitative modeling of bacterial abundances across the natural range of periodontal severities can distinguish which features of disease are associated with particular changes in composition. We assessed a cross-sectional cohort of 962 Malawian women for periodontal disease and used 16S rRNA gene amplicon sequencing (V5 to V7 region) to characterize the bacterial compositions of supragingival plaque samples. Associations between bacterial relative abundances and gingivitis/periodontitis were investigated by using negative binomial models, adjusting for epidemiological factors. We also examined bacterial cooccurrence networks to assess community structure. The main differences in supragingival plaque compositions were associated more with gingivitis than periodontitis, including higher bacterial diversity and a greater abundance of particular species. However, even after controlling for gingivitis, the presence of subgingival periodontitis was associated with an altered supragingival plaque. A small number of species were associated with periodontitis but not gingivitis, including members of Prevotella, Treponema, and Selenomonas, supporting a more complex disease model than a linear progression following gingivitis. Cooccurrence networks of periodontitis-associated taxa clustered according to periodontitis across all gingivitis severities. Species including Filifactor alocis and Fusobacterium nucleatum were central to this network, which supports their role in the coaggregation of periodontal biofilms during disease progression. Our findings confirm that periodontitis cannot be considered simply an advanced stage of gingivitis even when only considering supragingival plaque.

IMPORTANCE

Periodontal disease is a major public health problem associated with oral bacteria. While earlier studies focused on a small number of periodontal pathogens, it is now accepted that the whole bacterial community may be important. However, previous high-throughput marker gene sequencing studies of supragingival plaque have largely focused on high-income populations with good oral hygiene without including a range of periodontal disease severities. Our study includes a large number of low-income participants with poor oral hygiene and a wide range of severities, and we were therefore able to quantitatively model bacterial abundances as functions of both gingivitis and periodontitis. A signal associated with periodontitis remains after controlling for gingivitis severity, which supports the concept that, even when only considering supragingival plaque, periodontitis is not simply an advanced stage of gingivitis. This suggests the future possibility of diagnosing periodontitis based on bacterial occurrences in supragingival plaque.

Oral Health Knowledge, Attitudes, and Perceptions of Pregnant Kuwaiti Women

Good oral hygiene is known to prevent maternal gingivitis, but little is known about Kuwaiti pregnant women’s understanding and beliefs about maintaining and improving oral health during pregnancy. This qualitative study investigated perceptions, beliefs, and attitudes about oral health among Kuwaiti pregnant women and explored beliefs about maintaining and improving oral health during pregnancy. In-depth one-to-one interviews were conducted with a purposive sample of 19 Kuwaiti pregnant women across 7 government primary health care centers in Kuwait. A topic guide framed the questions, which explored pregnancy, oral health, oral health and pregnancy, oral health knowledge, and oral health behaviors. All interviews were digitally recorded, transcribed verbatim, and analyzed by thematic analysis. The key themes emerging from the data related to low oral health knowledge, unhelpful cultural beliefs concerning oral health during pregnancy, and lack of awareness about the effect of pregnancy on oral health. Pregnant women lacked motivation to seek dental care even when they considered dental treatment safe during pregnancy. Dentists’ purported incorrect beliefs about providing dental treatment to pregnant women and the women’s lack of motivation were identified as barriers to accessing oral health care and seeking oral health knowledge. Pregnant women in this study had not received the necessary oral health information to undertake appropriate oral health behaviors. Cultural beliefs and practices about oral health were identified that need to be tackled to improve and maintain positive oral health behaviors during pregnancy. Behavioral interventions must acknowledge the cultural sensitivity around beliefs during pregnancy and, as a first step, focus on correcting oral health knowledge among Kuwaiti pregnant women.

Knowledge Transfer Statement: The results of this qualitative study can be used by oral health care workers and researchers to plan and design more targeted dental health education interventions with pregnant women. The information in this study might be helpful to public health decision makers to make more appropriate decisions about implementing dental health education with pregnant women.

Longitudinal study on clinical and microbial analysis of periodontal status in pregnancy

This study was aimed to provide a longitudinal overview of the subgingival bacterial microbiome using fluorescence in situ hybridization (FISH) technique, in women in the second trimester of pregnancy (between 14 and 24 weeks), and 48 h and 8 weeks postpartum. Of 31 women evaluated during pregnancy, 24 returned for the 48-h and 18 for their 8-week exams postpartum. Probing depth (PD), bleeding on probing, clinical attachment level, and presence of calculus were recorded. Subgingival plaque samples were collected, and FISH was used to identify the numbers of eight periodontal pathogens. Friedman test was used to compare differences between follow-up examinations, followed by a multiple comparison test for a post hoc pairwise comparison. Clinically, a significantly greater number of teeth with PD = 4-5 mm were found during pregnancy than on postpartum examinations. Microbial analysis showed a statistically significant decrease in cell count over the study period for Prevotella nigrescens. P. intermedia, Campylobacter rectus, and Porphyromonas gingivalis also decrease, although not significantly, and Aggregatibacter actinomycetemcomitans increased. No significant changes were found for Fusobacterium nucleatum, Treponema denticola, or Tannerella forsythia. Our data demonstrate a change in the subgingival microbiota during pregnancy, at least for P. nigrescens.

Smoking, pregnancy and the subgingival microbiome

The periodontal microbiome is known to be altered during pregnancy as well as by smoking. However, despite the fact that 2.1 million women in the United States smoke during their pregnancy, the potentially synergistic effects of smoking and pregnancy on the subgingival microbiome have never been studied. Subgingival plaque was collected from 44 systemically and periodontally healthy non-pregnant nonsmokers (control), non-pregnant smokers, pregnant nonsmokers and pregnant smokers and sequenced using 16S-pyrotag sequencing. 331601 classifiable sequences were compared against HOMD. Community ordination methods and co-occurrence networks were used along with non-parametric tests to identify differences between groups. Linear Discriminant Analysis revealed significant clustering based on pregnancy and smoking status. Alpha diversity was similar between groups, however, pregnant women (smokers and nonsmokers) demonstrated higher levels of gram-positive and gram-negative facultatives, and lower levels of gram-negative anaerobes when compared to smokers. Each environmental perturbation induced distinctive co-occurrence patterns between species, with unique network anchors in each group. Our study thus suggests that the impact of each environmental perturbation on the periodontal microbiome is unique, and that when they are superimposed, the sum is greater than its parts. The persistence of these effects following cessation of the environmental disruption warrants further investigation.

Obesity and overweight: Impact on maternal and milk microbiome and their role for infant health and nutrition

Obesity, particularly in infants, is becoming a significant public health problem that has reached "epidemic" status worldwide. Obese children have an increased risk of developing obesity-related diseases, such as metabolic syndromes and diabetes, as well as increased risk of mortality and adverse health outcomes later in life. Experimental data show that maternal obesity has negative effects on the offspring's health in the short and long term. Increasing evidence suggests a key role for microbiota in host metabolism and energy harvest, providing novel tools for obesity prevention and management. The maternal environment, including nutrition and microbes, influences the likelihood of developing childhood diseases, which may persist and be exacerbated in adulthood. Maternal obesity and weight gain also influence microbiota composition and activity during pregnancy and lactation. They affect microbial diversity in the gut and breast milk. Such microbial changes may be transferred to the offspring during delivery and also during lactation, affecting infant microbial colonisation and immune system maturation. Thus, an adequate nutritional and microbial environment during the peri-natal period may provide a window of opportunity to reduce the risk of obesity and overweight in our infants using targeted strategies aimed at modulating the microbiota during early life.

16S rRNA gene-based metagenomic analysis reveals differences in bacteria-derived extracellular vesicles in the urine of pregnant and non-pregnant women

Recent evidence has indicated that bacteria-derived extracellular vesicles (EVs) are important for host–microbe communication. The aims of the present study were to evaluate whether bacteria-derived EVs are excreted via the urinary tract and to compare the composition of bacteria-derived EVs in the urine of pregnant and non-pregnant women. Seventy-three non-pregnant and seventy-four pregnant women were enrolled from Dankook University and Ewha Womans University hospitals. DNA was extracted from urine EVs after EV isolation using the differential centrifugation method. 16S ribosomal RNA (16S rRNA) gene sequencing was performed using high-throughput 454 pyrosequencing after amplification of the V1–V3 region of the 16S rDNA. The composition of 13 taxa differed significantly between the pregnant and non-pregnant women. At the genus level, Bacillus spp. EVs were more significantly enriched in the urine of the pregnant women than in that of the non-pregnant women (45.61% vs 0.12%, respectively). However, Pseudomonas spp. EVs were more dominant in non-pregnant women than in pregnant women (13.2% vs 4.09%, respectively). Regarding the compositional difference between pregnant women with normal and preterm delivery, EVs derived from Ureaplasma spp. and the family Veillonellaceae (including Megasphaera spp.) were more abundant in the urine of preterm-delivered women than in that of women with normal deliveries. Taken together, these data showed that Bacillus spp. EVs predominate in the urine of pregnant women, whereas Pseudomonas spp. EVs predominate in the urine of non-pregnant women; this suggests that Bacillus spp. EVs might have an important role in the maintenance of pregnancy.

Association between periodontal condition and subgingival microbiota in women during pregnancy: a longitudinal study

OBJECTIVE

In this study, the gingival conditions and the quantitative detection for Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis and Prevotella intermedia in pregnant women were determined.

MATERIAL AND METHODS

Quantitative determinations of periodontal bacteria by using a SyBr green system in women during pregnancy were performed. Women at the 2nd and 3rd trimesters of pregnancy and non-pregnant women were included in this study. A. actinomycetemcomitans was observed in high numbers in women at the 2nd and 3rd trimesters of pregnancy with a significant difference (p<0.05). F. nucleatum and P. intermedia were also observed in high levels.

RESULTS AND CONCLUSION

Our results show that pregnant women are more susceptible to gingivitis, and the presence of A. actinomycetemcomitans in subgingival biofilm might be taken into account for the treatment of periodontal disease.

Temporal and spatial variation of the human microbiota during pregnancy

Despite the critical role of the human microbiota in health, our understanding of microbiota compositional dynamics during and after pregnancy is incomplete. We conducted a case-control study of 49 pregnant women, 15 of whom delivered preterm. From 40 of these women, we analyzed bacterial taxonomic composition of 3,767 specimens collected prospectively and weekly during gestation and monthly after delivery from the vagina, distal gut, saliva, and tooth/gum. Linear mixed-effects modeling, medoid-based clustering, and Markov chain modeling were used to analyze community temporal trends, community structure, and vaginal community state transitions. Microbiota community taxonomic composition and diversity remained remarkably stable at all four body sites during pregnancy (P > 0.05 for trends over time). Prevalence of a Lactobacillus-poor vaginal community state type (CST 4) was inversely correlated with gestational age at delivery (P = 0.0039). Risk for preterm birth was more pronounced for subjects with CST 4 accompanied by elevated Gardnerella or Ureaplasma abundances. This finding was validated with a set of 246 vaginal specimens from nine women (four of whom delivered preterm). Most women experienced a postdelivery disturbance in the vaginal community characterized by a decrease in Lactobacillus species and an increase in diverse anaerobes such as Peptoniphilus, Prevotella, and Anaerococcus species. This disturbance was unrelated to gestational age at delivery and persisted for up to 1 y. These findings have important implications for predicting premature labor, a major global health problem, and for understanding the potential impact of a persistent, altered postpartum microbiota on maternal health, including outcomes of pregnancies following short interpregnancy intervals.

Interactions among urogenital, intestinal, skin, and oral infections in pregnant and lactating Panamanian Ngäbe women: a neglected public health challenge

Interrelationships among bacteria, protozoa, helminths, and ectoparasites were explored in a cross-sectional survey of 213 pregnant and 99 lactating indigenous women. Prevalences in pregnancy and lactation, respectively, were: vaginitis (89.2%; 46.8%), vaginal trichomoniasis (75.3%; 91.1%), bacterial vaginosis (BV; 60.6%; 63.3%), hookworm (56.6%; 47.8%), asymptomatic bacteriuria/urinary tract infection (AB/UTI; 56.2%; 36.2%), cervicitis (33.3%; 6.3%), vaginal yeast (24.9%; 11.4%), Ascaris (32.5%; 17.4%), vaginal diplococci (20.4%; 31.6%), caries (19.7%; 18.2%), scabies (17.4%; 8.1%), and Trichuris (12.5%; 8.7%). Multiple regressions revealed positive associations during pregnancy (trichomoniasis and AB/UTI; diplococci and Ascaris) and lactation (yeast and scabies). Negative associations were detected in pregnancy (BV and trichomoniasis; hookworm and diplococci) and lactation (BV and yeast). Vaginal Lactobacillus reduced odds of diplococci in pregnancy and lactation, but increased Ascaris eggs per gram (epg) and odds of trichomoniasis in pregnancy and yeast in lactation. These associations raised a concern that treatment of one condition may increase the risk of another.

Relationship between gingival inflammation and pregnancy

An increase in the prevalence and severity of gingival inflammation during pregnancy has been reported since the 1960s. Though the etiology is not fully known, it is believed that increasing plasma sex steroid hormone levels during pregnancy have a dramatic effect on the periodontium. Current works of research have shown that estrogen and progesterone increasing during pregnancy are supposed to be responsible for gingivitis progression. This review is focused not only on epidemiological studies, but also on the effects of progesterone and estrogen on the change of subgingival microbiota and immunologic physiological mediators in periodontal tissue (gingiva and periodontal ligament), which provides current information about the effects of pregnancy on gingival inflammation.

Mechanisms Involved in the Association between Periodontitis and Complications in Pregnancy

The association between periodontitis and some of the problems with pregnancy such as premature delivery, low weight at birth, and preeclampsia (PE) has been suggested. Nevertheless, epidemiological data have shown contradictory data, mainly due to differences in clinical parameters of periodontitis assessment. Furthermore, differences in microbial composition and immune response between aggressive and chronic periodontitis are not addressed by these epidemiological studies. We aimed to review the current data on the association between some of these problems with pregnancy and periodontitis, and the mechanisms underlying this association. Shifts in the microbial composition of the subgingival biofilm may occur during pregnancy, leading to a potentially more hazardous microbial community. Pregnancy is characterized by physiological immune tolerance. However, the infection leads to a shift in maternal immune response to a pathogenic pro-inflammatory response, with production of inflammatory cytokines and toxic products. In women with periodontitis, the infected periodontal tissues may act as reservoirs of bacteria and their products that can disseminate to the fetus-placenta unit. In severe periodontitis patients, the infection agents and their products are able to activate inflammatory signaling pathways locally and in extra-oral sites, including the placenta-fetal unit, which may not only induce preterm labor but also lead to PE and restrict intrauterine growth. Despite these evidences, the effectiveness of periodontal treatment in preventing gestational complications was still not established since it may be influenced by several factors such as severity of disease, composition of microbial community, treatment strategy, and period of treatment throughout pregnancy. This lack of scientific evidence does not exclude the need to control infection and inflammation in periodontitis patients during pregnancy, and treatment protocols should be validated.

Periodontal treatment outcomes during pregnancy and postpartum

OBJECTIVE

This study was conducted to compare periodontal therapy outcomes during pregnancy and after delivery.

MATERIALS AND METHODS

One hundred nine pregnant women up to the 20th gestational week (GW) were randomized into two groups: the test group (comprehensive periodontal therapy during pregnancy) and the control group (comprehensive periodontal therapy after delivery). Periodontal examinations comprised plaque index (PI), gingival index (GI), periodontal probing depth (PPD), clinical attachment level (CAL), bleeding on probing (BOP), and gingival crevicular fluid (GCF) volume. After baseline examination, women in the test group received periodontal treatment up to the 24th GW. The final examination was performed at the 26th to the 28th GW. Women in the control group were treated 30 days after delivery and reexamined 30 days after treatment.

RESULTS

Periodontal therapy significantly reduced periodontal inflammation in both groups. The mean percentage of sites with BOP was reduced from 49.14 % (±22.49) to 11.10 % (±7.84) and from 45.71 % (±17.86) to 8.07 % (±5.21) in the test and control groups, respectively (p = 0.95). No statistically significant differences were observed between groups concerning PI, GI, PPD, CAL, and GCF. The reduction in mean percentage of sites with BOP stratified for initial PPD ≥4 mm was higher in the control group (p < 0.01), but no differences were seen regarding GCF in these sites.

CONCLUSIONS

Hormonal changes during pregnancy do not interfere in treatment outcomes in women with widespread gingival inflammation and limited periodontal destruction. The role of these hormonal changes in pregnant women with different disease patterns remains uncertain.

CLINICAL RELEVANCE

Periodontal health can be reestablished irrespective of the hormonal challenge that takes place during pregnancy.

Association between maternal periodontitis and preterm and/or low birth weight infants in normal pregnancies

OBJECTIVE

To relate the periodontal condition with the presence of periodontal bacteria in pregnant that had babies with preterm delivery or/and low weight at birth (PTLBW).

METHODS

We recruited 134 pregnant women without systemic diseases attending at the Gynaecology and Obstetrics Room, from Maternal Provincial Hospital, Córdoba, Argentine. Pregnant were grouped according to the International Classification for a System of Periodontal Disease. A sample from periodontal pocket was extracted to identify Porphyromonas gingivalis (Pg), Treponema denticola (Td), Tannerella forsythia (Tf) Prevotella intermedia (Pi) and Agreggatibacter actinomycemcomitans (Aa).

RESULTS

We identified 7 (5%) cases of children born underweight or preterm of mothers diagnosed with Gingivitis, 6 (4%) in Mild Periodontitis and 4 (3%) in Moderate Periodontitis. We estimated that when Pi and/or Aa were not detected in the periodontal pockets of mothers, the infants had more than 129% chance of having normal birth weights (OR 3.47 for Pi and OR and 2.29 for Aa). The average age of the mothers who has PTLBW was 21 ± 3.5. The age showed an association with PTLBW (p < 0.0008).

CONCLUSIONS

The presences of periodontal pathogens in periodontal pockets from pregnant with different periodontal status would associate with PTLBW infants when the mothers are young, and the normal term and normal birth weight infant are associated with the absence of periodonto bacteria like Pi and Aa.

Effect of intensive oral hygiene regimen during pregnancy on periodontal health, cytokine levels, and pregnancy outcomes: a pilot study

BACKGROUND

Data are limited on the potential effect of intensive oral hygiene regimens and periodontal therapy during pregnancy on periodontal health, gingival crevicular fluid (GCF) and serum cytokines, and pregnancy outcomes.

METHODS

A clinical trial was conducted on 120 community-dwelling, 16- to 35-year-old pregnant women at 16 to 24 weeks of gestation. Each participant presented with clinical evidence of generalized, moderate-to-severe gingivitis. Oral hygiene products were provided, together with instructions for an intensive daily regimen of hygiene practices. Non-surgical therapy was provided at baseline. Oral examinations were completed at baseline and again at 4 and 8 weeks. In addition, samples of blood and GCF were collected at baseline and week 8. Mean changes in clinical variables and GCF and serum cytokine levels (interleukin [IL]-1β, IL-6, tumor necrosis factor [TNF]-α) between baseline and week 8 were calculated using paired t test. Pregnancy outcomes were recorded at parturition.

RESULTS

RESULTS indicated a statistically significant reduction in all clinical variables (P <0.0001) and decreased levels of TNF-α (P = 0.0076) and IL-1β (P = 0.0098) in GCF during the study period. The rate of preterm births (<37 weeks of gestation) was 6.7% (P = 0.113) and low birth weight (<2,500 g) was 10.2% (P = 1.00).

CONCLUSIONS

Among the population studied, intensive instructions and non-surgical periodontal therapy provided during 8 weeks at early pregnancy resulted in decreased gingival inflammation and a generalized improvement in periodontal health. Large-scale, randomized, controlled studies are needed to substantiate these findings.

Increased periodontal inflammation in women with preterm premature rupture of membranes

OBJECTIVES

To evaluate possible differences in periodontal inflammatory, microbiological and clinical parameters between women with preterm premature rupture of membranes (PPROM) and controls with uncomplicated pregnancies.

MATERIALS AND METHODS

Fifty-six women (32 test (PPROM) and 24 controls (uncomplicated pregnancies)) were examined at three time-points (T1: gestational weeks 20-35, T2: within 48 h after parturition, T3: 4-6 weeks after parturition). The examinations included assessment of the Periodontal Screening Index, collection of gingival crevicular fluid (GCF) and subgingival as well as vaginal bacterial sampling.

RESULTS

Periodontal inflammation was found to be higher in the test compared with the control group (p < 0.05) and decreased over time in both groups (p < 0.05). Microbiological outcomes showed no intergroup differences (p > 0.05) in prevalence of bacteria, but a decrease in subgingival periodontopathogens from T1 to T2 in the test group (p < 0.05) was observed. Interleukin (IL)-1β levels in GCF at T2 were not different between groups (p > 0.05). In women with PPROM, GCF levels of IL-8 (p < 0.05) and C-reactive protein (p < 0.05) were lower and IL-10 levels higher (p < 0.05) compared with controls.

CONCLUSIONS

Periodontal inflammation is elevated during pregnancy and seems to be more pronounced in women with PPROM.

CLINICAL RELEVANCE

The findings of the present study revealed an association between periodontal inflammation and PPROM, thus emphasizing the importance of optimizing self-performed oral hygiene in pregnant women.

Association between polycystic ovary syndrome, oral microbiota and systemic antibody responses

Polycystic ovary syndrome (PCOS) is a hormonal disorder of women that not only is the leading cause of infertility but also shows a reciprocal link with oral health. This study aimed to investigate the hypothesis that the levels of putative periodontal pathogens in saliva and their antibody response in serum are elevated in PCOS, compared to systemic health. A total of 125 women were included in four groups; 45 women with PCOS and healthy periodontium, 35 women with PCOS and gingivitis, 25 systemically and periodontally healthy women, 20 systemically healthy women with gingivitis. Salivary levels of seven putative periodontal pathogens were analyzed by quantitative real-time polymerase chain reaction and serum antibody levels were analyzed by ELISA. In women with PCOS, salivary Porphyromonas gingivalis, Fusobacterium nucleatum, Streptococcus oralis and Tannerella forsythia levels were higher than matched systemically healthy women, particularly in the case of gingivitis. Aggregatibacter actinomycetemcomitans and Treponema denticola levels were similar among study groups. The presence of PCOS also enhanced P. gingivalis, Prevotella intermedia and S. oralis serum antibody levels, when gingivitis was also present. Gingival inflammation correlated positively with levels of the studied taxa in saliva, particularly in PCOS. The presence of P. gingivalis and F. nucleatum in saliva also exhibited a strong positive correlation with the corresponding serum antibody levels. In conclusion, as an underlying systemic endocrine condition, PCOS may quantitatively affect the composition of oral microbiota and the raised systemic response to selective members of this microbial community, exerting a confounding role in resultant gingival inflammation and periodontal health. The most consistent effect appeared to be exerted on P. gingivalis.

Prevalence of Clinical Periodontitis and Putative Periodontal Pathogens among South Indian Pregnant Women

In view of recent understanding of the association of periodontal infections and adverse pregnancy outcomes, the present investigation was undertaken to study the periodontal infections among 390 asymptomatic pregnant women and to find an association of bacterial etiologies with the disease. Prevalence of gingivitis was 38% and clinical periodontitis was 10% among the study population. Subgingival plaque specimens were subjected to multiplex PCR targeting ten putative periodontopathogenic bacteria. Among the periodontitis group, high detection rates of Porphyromonas gingivalis (56%), Prevotella nigrescens (44%), Treponema denticola (32%), and Prevotella intermedius (24%) were noted along with significant association with the disease (P < 0.05).