Effects of periodontal therapy during pregnancy on periodontal status, biologic parameters, and pregnancy outcomes: a pilot study

Role of periodontal treatment in pregnancy gingivitis and adverse outcomes: a systematic review and meta-analysis

BACKGROUND

Pregnancy gingivitis is a common oral health issue that affects both maternal and fetal health. This study aims to evaluate the effectiveness of periodontal treatment in preventing pregnancy gingivitis, preterm birth, and low birth weight through a systematic review and meta-analysis of randomized controlled trials (RCTs).

METHODS

A systematic review and meta-analysis were conducted following PRISMA guidelines. A comprehensive literature search was performed across CINAHL, Scopus, Cochrane, and PubMed/Medline databases from 2000 to the present. Study selection and data extraction were independently carried out by two reviewers. Statistical analyses, including heterogeneity tests, sensitivity analysis, and publication bias assessment, were conducted using RevMan 5.4 and R software.

RESULTS

A total of 13 studies were included. The meta-analysis indicated that periodontal treatment might have a potential effect on preventing pregnancy gingivitis, but this was not statistically significant (OR = 0.85, 95% CI [0.68, 1.06], I2 = 51%). Subgroup analysis revealed that periodontal treatment significantly reduced the rates of preterm birth and low birth weight in lower-quality studies, but no significant effects were observed in higher-quality studies. Sensitivity analysis and publication bias tests confirmed the stability and reliability of the results.

CONCLUSION

While lower-quality studies suggest that periodontal treatment may positively impact pregnancy gingivitis, preterm birth, and low birth weight, these effects were not supported by higher-quality evidence. Further well-designed RCTs are needed to confirm these findings and ensure their reliability. Periodontal treatment could potentially be considered as part of prenatal care to improve maternal oral health and pregnancy outcomes.

Oral Pathogens' Substantial Burden on Cancer, Cardiovascular Diseases, Alzheimer's, Diabetes, and Other Systemic Diseases: A Public Health Crisis-A Comprehensive Review

This review synthesizes the findings from 252 studies to explore the relationship between the oral pathogens associated with periodontitis, dental caries, and systemic diseases. Individuals with oral diseases, such as periodontitis, are between 1.7 and 7.5 times (average 3.3 times) more likely to develop systemic diseases or suffer adverse pregnancy outcomes, underscoring the critical connection between dental and overall health. Oral conditions such as periodontitis and dental caries represent a significant health burden, affecting 26-47% of Americans. The most important oral pathogens, ranked by publication frequency, include the herpes virus, C. albicans, S. mutans, P. gingivalis, F. nucleatum, A. actinomycetemcomitans, P. intermedia, T. denticola, and T. forsythia. The systemic diseases and disorders linked to oral infections, ranked similarly, include cancer, respiratory, liver, bowel, fever, kidney, complications in pregnancy, cardiovascular bacteremia, diabetes, arthritis, autoimmune, bladder, dementia, lupus, and Alzheimer's diseases. Evidence supports the efficacy of dental and periodontal treatments in eliminating oral infections and reducing the severity of systemic diseases. The substantial burden that oral pathogens have on cancer, cardiovascular diseases, Alzheimer's, diabetes, and other systemic diseases poses a significant public health crisis.

The impact of scaling and root planning combined with mouthwash during pregnancy on preterm birth and low birth weight: a systematic review and meta-analysis

BACKGROUND

The effect of treating periodontal disease (PD) during pregnancy on adverse birth outcomes, such as preterm birth (PTB) and/or low birth weight (LBW), remains unclear. This is partially due to the fact that Randomized Controlled Trials (RCTs) have used different combinations of treatment approaches to test this hypothesis. In this meta-analysis of RCTs, we assessed the impact of treating PD during pregnancy with scaling and root planning (SRP) and mouthwash use on PTB and LBW.

METHODS

A systematic review with meta-analysis was conducted following PRISMA guidelines. A comprehensive search strategy was employed across electronic databases, including PubMed/Medline, Embase, and Google Scholar. Quality assessment was performed using the Cochrane Risk of Bias 2 Tool. Pooled risk ratios (RRs) with 95% confidence intervals (CIs) were calculated using random-effect models.

RESULTS

Out of 133 initially identified reports, 9 RCTs involving 3,985 pregnant women met the inclusion criteria. Periodontal treatment with SRP and mouthwash use in pregnancy was associated with a lower risk of PTB and LBW in meta-analysis with random effects models (pooled RR for PTB = 0.44, 95% CI: 0.22-0.88) and (pooled RR for LBW = 0.33, 95% CI: 0.13-0.84). Substantial heterogeneity was observed among studies (I2 = 91% and 90% for PTB and LBW, respectively), with sensitivity analysis suggesting potential sources of heterogeneity. Funnel plot assessment for publication bias showed evidence of asymmetry.

CONCLUSION

SRP with mouthwash use during pregnancy were associated with significantly lower risks of PTB and LBW. Larger, well-conducted RCTs are warranted to address this issue, as existing trials are small and exhibit methodological and statistical heterogeneity.

Effects of different periodontal interventions on the risk of adverse pregnancy outcomes in pregnant women: a systematic review and network meta-analysis of randomized controlled trials

Background

Periodontal disease is widespread among pregnant women, and it is possible that taking action to improve oral health conditions can make improvements in adverse pregnancy outcomes. Herein, we summarize the recent evidence using a network meta-analysis to assess the effects of different periodontal treatment intervention strategies on the risk of adverse pregnancy outcomes in pregnant women.

Materials and methods

Randomized controlled trials were retrieved from PubMed, Web of Science, Embase, and Cochrane Library databases. After literature screening, data extraction, and quality evaluation of the included literature were performed, the R studio 4.2.2 "netmeta" package was used for the network meta-analysis.

Results

A total of 20 studies were included, and 5 adverse pregnancy outcomes (preterm birth, low birth weight, preterm birth and/or low birth weight infants, small for gestational age, and pre-eclampsia) were considered to examine the effects of different periodontal treatment interventions strategies on the risk of the abovementioned outcome indicators. The results of the network meta-analysis demonstrated that the three periodontal treatment intervention strategies of sub- and/or supra-gingival scaling and root planing + chlorhexidine rinsing (SRP + CR), sub- and/or supra-gingival scaling and root planing+chlorhexidine rinsing + tooth polishing and plaque control (SRP + CR + TP), and sub- and/or supra-gingival scaling and root planing +sonic toothbrush + tooth polishing and plaque control (SRP + ST + TP) reduced the risk of preterm birth [odds ratio (OR) = 0.29, 95% confidence interval (CI) (0.10-0.88), OR = 0.25, 95CI% (0.10-0.63), OR = 0.28, 95CI% (0.11-0.69), respectively]. In addition, two periodontal treatment intervention strategies, SRP + CR and SRP + CR + TP, were effective methods in terms of the risk of preterm birth and/or low birth weight [OR = 0.18, 95CI% (0.06-0.52), OR = 0.31, 95CI% (0.12-0.79)].

Conclusion

The available evidence suggests that the risk of preterm birth and preterm birth and/or low birth weight can be reduced with certain periodontal treatment intervention strategies. Future studies should focus on optimizing intervention strategies and the optimal timing for different periods of pregnancy, in order to provide a reference for pregnant women's healthcare.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=407901, CRD42023407901.

Effect of Treating Periodontal Disease in Pregnant Women to Reduce the Risk of Preterm Birth and Low Birth Weight: An Umbrella Review

Background: The aim of this review was to evaluate the effects of periodontal disease (PD) treatment in pregnant women to reduce the risk of preterm birth (PB) and low birth weight (LBW) by conducting an umbrella review. Methods: A comprehensive search for the literature up to April 2024 was conducted across multiple databases including PubMed, Cochrane Library, Scopus, EMBASE, Scielo, Web of Science, Google Scholar, Proquest Dissertations and Theses, and OpenGrey. We specifically targeted systematic reviews (SRs) with or without meta-analyses, irrespective of language or time constraints, focusing on primary studies examining the effect of PD treatment in pregnant women to reduce the risk of PB and LBW. Various types of non-systematic reviews, intervention studies, observational studies, preclinical and basic research, summaries, comments, case reports, protocols, personal opinions, letters, and posters were excluded from consideration. The quality and overall confidence of the included studies were assessed using the AMSTAR-2 tool. Results: After the initial search, 232 articles were identified, of which only 24 met the selection criteria after exclusion. The majority of these studies indicated that periodontal treatment reduces the risk of PB and LBW. Conclusions: According to the findings and conclusions drawn from the SRs with a high overall confidence level, PD treatment in pregnant women reduces the risk of PB and LBW.

Awareness of Periodontal Health among Pregnant Females in Government Setting in United Arab Emirates

OBJECTIVE

 Periodontal disease is one of the most common infectious diseases. Several factors are associated with increased susceptibility of periodontal disease such as hormonal changes during pregnancy. Although pregnancy does not directly cause gingivitis, it can aggravate preexisting periodontal disease. This study aimed to evaluate knowledge of the association between periodontal disease and pregnancy in pregnant females.

MATERIALS AND METHODS

 A convenience sample of pregnant females attending two United Arab Emirates government hospitals was recruited for this study. A 23-item questionnaire was developed with four sections, covering sociodemographic details, oral hygiene, oral symptoms during pregnancy, and knowledge of periodontal health during pregnancy. The study was conducted between April and October 2017. All participants consented to the survey.

RESULTS

 A total of 100 participants with a mean age of 31 years (± 5.9) completed the survey. Most respondents brushed their teeth 2 to 3 times a day (65%), used a manual toothbrush (93%) but only visited the dentist when in pain (62%). Few respondents self-reported any gingival signs and symptoms during pregnancy; 38% had bleeding gums, 27% had no gum swelling, and 34% had bad odor/taste/smell. Only 21% of pregnant females lost a tooth/teeth during pregnancy, 15% believed that pregnancy increased the likelihood of gum disease, and 66% of gynecologists did not advise a visit to the dentist.Housewives were significantly less knowledgeable about periodontal health than students/employed respondents (p = 0.01). Quality of knowledge was not associated with educational attainment (< 0.06). Respondents > 30 years of age were more likely to believe in "a tooth for a baby" than younger participants aged < 30 years (p < 0.05). A logistic regression model showed that educational attainment was not a predictor for the belief in "a tooth for a baby" but age was a significant predictor (odds ratio = 2.0).

CONCLUSION

 Protocols should be developed in antenatal clinics in order to improve periodontal health in pregnant females and to prevent complications that can result in adverse pregnancy outcomes.

Systematic review and meta-analysis of randomized controlled trials evaluating the efficacy of non-surgical periodontal treatment in patients with concurrent systemic conditions

OBJECTIVE

To conduct a systematic review of the published scientific evidence to evaluate the efficacy of nonsurgical periodontal therapy (NSPT) in treating periodontitis in patients with concurrent systemic conditions (diabetes, CVD, erectile dysfunction, chronic kidney disease, rheumatoid arthritis, polycystic ovarian syndrome, obesity, pregnancy). We hypothesised that NSPT results in better periodontal outcomes when compared to untreated controls after follow-up.

MATERIALS AND METHODS

A systematic search (PUBMED/EMBASE) was conducted from 1995 to 2023 to identify randomised controlled trials (RCTs) with a minimum follow-up of 3 months. The primary outcome was the difference in mean probing depth (PD), and the secondary outcomes were mean clinical attachment loss (CAL), percentage of sites with PD ≤ 3 mm (%PD ≤ 3 mm) and percentage of sites with bleeding on probing (%BOP) between the treated and untreated control group in patients with comorbidities.

RESULTS

The electronic search resulted in 2,403 hits. After removing duplicates, 1,565 titles and abstracts were screened according to the eligibility criteria, resulting in 126 articles for full-text screening. Following this, 44 studies were analysed. Restricting to studies with low bias or some concerns, NSPT group demonstrated a 0.55 mm lower mean PD (95%CI: -0.69; -0.41) after 3 months compared to the control group.

CONCLUSION

Compared to the untreated controls, NSPT notably reduced mean PD, mean CAL, and %BOP while increasing %PD ≤ 3 mm in patients with concurrent systemic conditions. These findings suggest that NSPT is also an effective procedure in managing periodontitis in patients with concurrent systemic conditions.

TRIAL REGISTRATION

This systematic review was registered under the protocol registration number CRD42021241517/PROSPERO.

Endogenous and microbial biomarkers for periodontitis and type 2 diabetes mellitus

It has been well documented that there is a two-way relationship between diabetes mellitus and periodontitis. Diabetes mellitus represents an established risk factor for chronic periodontitis. Conversely, chronic periodontitis adversely modulates serum glucose levels in diabetic patients. Activated immune and inflammatory responses are noted during diabetes and periodontitis, under the modulation of similar biological mediators. These activated responses result in increased activity of certain immune-inflammatory mediators including adipokines and microRNAs in diabetic patients with periodontal disease. Notably, certain microbes in the oral cavity were identified to be involved in the occurrence of diabetes and periodontitis. In other words, these immune-inflammatory mediators and microbes may potentially serve as biomarkers for risk assessment and therapy selection in diabetes and periodontitis. In this review, we briefly provide an updated overview on different potential biomarkers, providing novel diagnostic and therapeutic insights on periodontal complications and diabetes mellitus.

Allocation concealment appraisal of clinical therapy trials using the extended Composite Quality Score (CQS-2)-An empirically based update

Objectives

The objective of this study was to revise CQS-2/Criterion II concerning allocation concealment appraisal for prospective, controlled clinical therapy trials.

Methods

Meta-analyses of trials with inadequate allocation concealment were tested for in-between trial heterogeneity (I2 > 0) due to imbalances in baseline variables. Meta-analyses with positive test results were used as a basis to deduce criteria for adequate allocation concealment. The CQS-2/Criterion II was reformulated in line with the findings.

Result

One suitable meta-analysis was identified. Two forest plots with data from five and four trials with inadequate/unclear allocation concealment were selected for testing. In addition, a total of five trials with adequate allocation concealment were identified. The meta-analysis test results were positive, and keywords for the judgment of adequate allocation concealment were extracted verbatim from the text of the meta-analysis. The extracted keywords indicated "central allocation" as the main criterion for adequate allocation concealment. Criterion II of the CQS-2 was revised accordingly.

Conclusion

Criterion II of the CQS-2 trial appraisal tool was revised. The revised appraisal tool was specified as version CQS-2B.

The potential role of the gingival crevicular fluid biomarkers in the prediction of pregnancy complications

Early and minimally invasive methods are required to predict the risk of multiple adverse pregnancy outcomes. A potential technique with growing interest utilizes the gingival crevicular fluid (GCF), a physiological serum exudate found in the healthy gingival sulcus and in the periodontal pocket in inflammatory conditions. Analysis of biomarkers in the GCF is a minimally invasive method that can be feasible and cost-effective. The potential use of GCF biomarkers along with other clinical indicators in early pregnancy may provide reliable predictors of several adverse pregnancy outcomes, therefore, reducing both maternal and fetal morbidities. Various studies have reported that increased or decreased concentrations of different biomarkers in GCF are associated with a high risk of developing pregnancy complications. In particular, such associations have been commonly demonstrated with gestational diabetes, pre-eclampsia, and pre-term birth. However, limited evidence is available regarding other pregnancy complications such as preterm premature rupture of membranes, recurrent miscarriage, small for gestational age, and hyperemesis gravidarum. In this review, we discuss the reported association between individual GCF biomarkers and common pregnancy complications. Future research is required to provide more solid evidence of the predictive value of those biomarkers in estimating women's risk for each disorder.

Maternal Periodontal Status as a Factor Influencing Obstetrical Outcomes

Background and Objectives: Preterm birth as a complex phenomenon is influenced by numerous endogenic and exogenic factors, although its exact cause often remains obscure. According to epidemiological studies, maternal periodontal diseases, in addition to affecting general health, can also cause adverse pregnancy outcomes. Nonetheless, the existing results in the literature regarding this topic remain controversial. Consequently, our study aimed to determine the connection between poor maternal periodontal status and neonatal birth weight. Materials and Methods: A total of 111 primigravida-primiparous pregnant, healthy women underwent a periodontal examination in the second trimester of their pregnancies. Probing depth (PD) and bleeding on probing (BOP) were determined, and based on these diagnostic measurements, the patients were divided into three subgroups according to their dental status: healthy (H, n = 17), gingivitis (G, n = 67), and periodontitis (P, n = 27). Results: Considering that poor maternal oral status is an influencing factor for obstetrical outcomes, the presence of PD and BOP (characterized by the sulcus bleeding index, SBI) was evaluated. In the case of P, defined as PD ≥ 4 mm in at least one site and BOP ≥ 50% of the teeth, a significant correlation between BOP and a low neonatal birth weight at delivery (p = 0.001) was found. An analysis of the relationship between SBI and gestational age (GA) at the time of the periodontal examination in the different dental status groups showed a significant correlation between these parameters in the G group (p = 0.04). Conclusions: Our results suggest that a worse periodontal status during pregnancy may negatively affect obstetrical outcomes, especially the prematurity rate and newborn weight. Therefore, the importance of periodontal screening to prevent these complications is undeniable.

Inflammatory Response in Oral Biofilm during Pregnancy: A Systematic Review

Understanding the inflammatory response in oral biofilm during pregnancy and its association with oral and maternal health is essential for identifying biomarker patterns that may serve as markers of pregnancy-related complications. We aimed to conduct a systematic review of the available literature to assess: (1) inflammatory responses in oral biofilm during pregnancy, (2) the association between inflammatory responses in oral biofilm during pregnancy and maternal, oral or systemic conditions, (3) changes in the response of inflammatory biomarkers found in the oral biofilm during different pregnancy stages, and (4) the value of other risk factors such as nutrition and lifestyle. PubMed, Web of Science and Cochrane Library were systematically searched from inception until April 2022. From 5441 records, 39 studies were included for qualitative assessment. The oral biofilm in pregnant women was associated with increased inflammatory biomarkers when compared to non-pregnant women. Levels of inflammatory biomarkers in the oral biofilm were found to be highest in pregnant women with systemic conditions. Increased inflammatory biomarkers in the oral biofilm were also associated with worse oral health outcomes. Given the importance of nutrition and lifestyle for pregnancy and oral health outcomes and the fact that these factors were largely excluded in the included studies, future research should consider a holistic view of the mother during pregnancy to capture physiological, hormonal, immunologic, and metabolic changes in the context of inflammatory responses.

Periodontal therapy for primary or secondary prevention of cardiovascular disease in people with periodontitis

BACKGROUND

There may be an association between periodontitis and cardiovascular disease (CVD); however, the evidence so far has been uncertain about whether periodontal therapy can help prevent CVD in people diagnosed with chronic periodontitis. This is the third update of a review originally published in 2014, and most recently updated in 2019. Although there is a new multidimensional staging and grading system for periodontitis, we have retained the label 'chronic periodontitis' in this version of the review since available studies are based on the previous classification system.

OBJECTIVES

To investigate the effects of periodontal therapy for primary or secondary prevention of CVD in people with chronic periodontitis.

SEARCH METHODS

An information specialist searched five bibliographic databases up to 17 November 2021 and additional search methods were used to identify published, unpublished, and ongoing studies. We also searched the Chinese BioMedical Literature Database, the China National Knowledge Infrastructure, the VIP database, and Sciencepaper Online to March 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared active periodontal therapy to no periodontal treatment or a different periodontal treatment. We included studies of participants with a diagnosis of chronic periodontitis, either with CVD (secondary prevention studies) or without CVD (primary prevention studies).

DATA COLLECTION AND ANALYSIS

Two review authors carried out the study identification, data extraction, and 'Risk of bias' assessment independently and in duplicate. They resolved any discrepancies by discussion, or with a third review author. We adopted a formal pilot-tested data extraction form, and used the Cochrane tool to assess the risk of bias in the studies. We used GRADE criteria to assess the certainty of the evidence.

MAIN RESULTS

There are no new completed RCTs on this topic since we published our last update in 2019. We included two RCTs in the review. One study focused on the primary prevention of CVD, and the other addressed secondary prevention. We evaluated both as being at high risk of bias. Our primary outcomes of interest were death (all-cause and CVD-related) and all cardiovascular events, measured at one-year follow-up or longer. For primary prevention of CVD in participants with periodontitis and metabolic syndrome, one study (165 participants) provided very low-certainty evidence. There was only one death in the study; we were unable to determine whether scaling and root planning plus amoxicillin and metronidazole could reduce incidence of all-cause death (Peto odds ratio (OR) 7.48, 95% confidence interval (CI) 0.15 to 376.98), or all CVD-related death (Peto OR 7.48, 95% CI 0.15 to 376.98). We could not exclude the possibility that scaling and root planning plus amoxicillin and metronidazole could increase cardiovascular events (Peto OR 7.77, 95% CI 1.07 to 56.1) compared with supragingival scaling measured at 12-month follow-up. For secondary prevention of CVD, one pilot study randomised 303 participants to receive scaling and root planning plus oral hygiene instruction (periodontal treatment) or oral hygiene instruction plus a copy of radiographs and recommendation to follow-up with a dentist (community care). As cardiovascular events had been measured for different time periods of between 6 and 25 months, and only 37 participants were available with at least one-year follow-up, we did not consider the data to be sufficiently robust for inclusion in this review. The study did not evaluate all-cause death and all CVD-related death. We are unable to draw any conclusions about the effects of periodontal therapy on secondary prevention of CVD.

AUTHORS' CONCLUSIONS

For primary prevention of cardiovascular disease (CVD) in people diagnosed with periodontitis and metabolic syndrome, very low-certainty evidence was inconclusive about the effects of scaling and root planning plus antibiotics compared to supragingival scaling. There is no reliable evidence available regarding secondary prevention of CVD in people diagnosed with chronic periodontitis and CVD. Further trials are needed to reach conclusions about whether treatment for periodontal disease can help prevent occurrence or recurrence of CVD.

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.

A Successful Dental Care Referral Program for Low-Income Pregnant Women in New York

Despite evidence-based guidelines that advocate for dental care during pregnancy, dental utilization among pregnant women remains low, especially among low-income and racial-ethnic minority women. We investigated self-reported dental care referral and self-reported dental care attendance among a group of 298 low-income, largely racial-ethnic minority pregnant women attending two suburban prenatal care clinics that had integrated dental care referrals into their prenatal care according to these guidelines. We administered a questionnaire that asked women: (1) whether they had been referred for care by their prenatal care provider; (2) whether they had been seen by a dentist during pregnancy. Among those women who were eligible for a dental care referral (those who reported having dental symptoms, and those not having a recent dental visit), we found that 73.0% reported that they had indeed been referred for dental care by their prenatal provider, while the remaining women reported either no referral (23.5%, n = 67) or were not sure whether they had been referred (3.5%, n = 10). Among those who reported a dental care referral, 67.3% (n = 140) reported that they saw a dentist during their pregnancy, while of those who reported no dental care referral only 35.1% (n = 27) reported a dental visit (Chi-Sq. = 24.1, df = 1, p < 0.001). Having received a dental referral was a significant predictor of reporting a dental visit during pregnancy, with women who received a referral being 4.6 times more likely to report a dental visit during pregnancy compared to those women who did not report a referral. These results demonstrate that vulnerable pregnant women referred for dental care by their prenatal provider will indeed seek and utilize dental care when offered. This dental referral program may serve as a model for improving the utilization of dental care among this population.

Impact of the treatment of periodontitis on systemic health and quality of life: A systematic review

AIM

To investigate the effect of treatment of periodontitis on systemic health outcomes, pregnancy complications, and associated quality of life.

MATERIALS AND METHODS

Systematic electronic searches were conducted to identify randomized controlled trials with minimum 6-month follow-up and reporting on the outcomes of interest. Qualitative and quantitative analyses were performed as deemed suitable.

RESULTS

Meta-analyses confirmed reductions of high-sensitivity C-reactive protein (hs-CRP) [0.56 mg/L, 95% confidence interval (CI) (-0.88, -0.25), p < .001]; interleukin (IL)-6 [0.48 pg/ml, 95% CI (-0.88, -0.08), p = .020], and plasma glucose [1.33 mmol/l, 95% CI (-2.41, -0.24), p = .016], and increase of flow-mediated dilation (FMD) [0.31%, 95% CI (0.07, 0.55), p = .012] and diastolic blood pressure [0.29 mmHg, 95% CI (0.10, 0.49), p = .003] 6 months after the treatment of periodontitis. A significant effect on preterm deliveries (<37 weeks) was observed [0.77 risk ratio, 95% CI (0.60, 0.98), p = .036]. Limited evidence was reported on quality-of-life (QoL) outcomes in the included studies.

CONCLUSIONS

Treatment of periodontitis results in systemic health improvements including improvement in cardiometabolic risk, reduction in systemic inflammation and the occurrence of preterm deliveries. Further research is however warranted to confirm whether these changes are sustained over time. Further, appropriate QoL outcomes should be included in the study designs of future clinical trials.

Changes in Candida albicans, Streptococcus mutans and oral health conditions following Prenatal Total Oral Rehabilitation among underserved pregnant women

Objectives

To assess the oral health condition and oral microbial outcomes from receiving an innovative treatment regimen - Prenatal Total Oral Rehabilitation (PTOR).

Methods

This prospective cohort study included 15 pregnant women in the PTOR group who had a baseline visit before PTOR and three follow-up visits (immediate after, 2 weeks and 2 months) after receiving PTOR. A historical control group of additional 15 pregnant women was matched from a separate study based on a propensity score. Along with demographic and medical background, oral health conditions and perinatal oral health literacy were assessed. Oral samples (saliva and plaque) were analyzed to identify and quantify Streptococcus mutans and Candida species by culturing-dependent and -independent methods.

Results

Significant reductions of salivary S. mutans were observed following PTOR, the effect remained until 2-month follow-up (p < 0.05). The carriage of salivary and plaque S. mutans at the 2-month visit of the PTOR group was significantly lower than that of the control group (p < 0.05). Oral health conditions reflected by BOP and PI were significantly improved upon receiving PTOR (p < 0.05). Receiving PTOR significantly improved the perinatal oral health literacy score, and the knowledge retained until 2-month follow-up (p < 0.05).

Conclusions

PTOR is associated with an improvement in oral health conditions and perinatal oral health literacy, and a reduction in S. mutans carriage, within a 2-month follow-up period. Future clinical trials are warranted to comprehensively assess the impact of PTOR on the maternal oral flora other than S. mutans and Candida, birth outcomes, and their offspring's oral health.

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.

Oral Microbiota of Children Is Conserved across Han, Tibetan and Hui Groups and Is Correlated with Diet and Gut Microbiota

The oral microbiota can be affected by several factors; however, little is known about the relationship between diet, ethnicity and commensal oral microbiota among school children living in close geographic proximity. In addition, the relationship between the oral and gut microbiota remains unclear. We collected saliva from 60 school children from the Tibetan, Han and Hui ethnicities for a 16S rRNA gene sequencing analysis and comparison with previously collected fecal samples. The study revealed that Bacteroidetes and Proteobacteria were the dominant phyla in the oral microbiota. The Shannon diversity was lowest in the Tibetan group. A PCA showed a substantial overlap in the distribution of the taxa, indicating a high degree of conservation among the oral microbiota across ethnic groups while the enrichment of a few specific taxa was observed across different ethnic groups. The consumption of seafood, poultry, sweets and vegetables was significantly correlated with multiple oral microbiotas. Furthermore, 123 oral genera were significantly associated with 191 gut genera. A principal coordinate analysis revealed that the oral microbiota clustered separately from the gut microbiota. This work extends the findings of previous studies comparing microbiota from human populations and provides a basis for the exploration of the interactions governing the tri-partite relationship between diet, oral microbiota and gut microbiota.

Regulation of matrix metalloproteinases-8, -9 and endogenous tissue inhibitor-1 in oral biofluids during pregnancy and postpartum

OBJECTIVE

During pregnancy, mothers undergoe considerable physiological changes affecting the whole body including periodontal tissues. Susceptibility to gingival inflammation during pregnancy could be mediated by modulation of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs). Therefore, the aim of this study was to investigate salivary and gingival crevicular fluid (GCF) levels of MMPs and TIMPs during the second and third trimester of pregnancy and postpartum.

DESIGN

Saliva and GCF samples were collected from 96 pregnant women (PW) before and after giving birth. The sixty matched non-pregnant women (N-PW) were recruited as a control group and full-mouth periodontal examination was performed. The levels of MMP-8, MMP-9 and TIMP-1 were determined by immunofluorometric and enzyme-linked immunosorbent assays.

RESULTS

The PW group exhibited significantly higher levels of MMP-8 and MMP-9 in their saliva than the N-PW group while corresponding salivary TIMP-1 levels were significantly lower in NPW compared to the postpartum stage. This resulted in significantly higher MMP-8/TIMP-1 and MMP-9/TIMP-1ratio in the saliva from PW before and after birth than in that from N-PW. MMP-8, MMP-9 and TIMP-1 levels were higher in GCF from PW and postpartum than in that from N-PW.

CONCLUSIONS

MMP-8 and MMP-9 levels in saliva and GCF reflect inflammatory burden during pregnancy. They could be used for monitoring the inflammatory state of gingival tissues during pregnancy.

Are diabetes and dental care providers in the Republic of Mauritius advising patients about the importance of oral health in diabetes management?

Diabetes and dental care providers may greatly contribute in the early detection of oral diseases and diabetes, respectively, and in the prevention of complications of diabetes. However, there is limited collaboration and referrals between these two groups of health professionals.

OBJECTIVE

To investigate whether diabetic providers are addressing the importance of oral care in the management of diabetes and whether dental care providers are advising their patients with diabetes about the importance of glycaemic control.

METHOD

Descriptive statistics was used to report data collected from 720 patients with diabetes using a closed-end questionnaire. Logistic regression analysis revealed the factors significantly impacting whether participants received advice from healthcare providers.

RESULTS

The majority of participants did not receive advice from either diabetes (84%) or dental (75%) care providers regarding the reciprocal nature of diabetes and periodontitis. The factors significantly affecting receiving advice from diabetes care providers were place of residence (p = 0.003), self-reported type of diabetes (p = 0.000) receiving advice from dental care providers (p = 0.000); from dental care providers - education (p = 0.020), place of residence (p = 0.004), the number of years since diagnosis of diabetes (p = 0.002), frequency of dental visits (p = 0.000) and receiving advice from diabetes care providers (p = 0.000).

CONCLUSION

Diabetes and dental care providers in Mauritius are not addressing oral health care as an essential component of diabetes care. Patients with diabetes are neither being advised about the importance of regular dental visits by their treating doctor, nor about the importance of glycaemic control in the prevention of oral complications by their dentist.

Maternal periodontal status, oral inflammatory load, and systemic inflammation are associated with low infant birth weight

BACKGROUND

Periodontal disease and pregnancy outcomes have been claimed to be associated with conflicting reports. The purpose of this study was to prospectively examine the association between maternal periodontal status, oral inflammatory load and serum C- reactive protein (CRP) level, and infant birth weight.

METHODS

A total of 156 pregnant women (age 26.62 ± 3.93 years) within the gestational age group of 13 to 32 weeks participated in this cross-sectional study. Oral inflammatory load (OIL) was assessed in a salivary rinse sample using fluorescence microscopy. Clinical periodontal parameters were recorded and serum C-reactive protein level (CRP) was assessed. Participants were followed till delivery, details of parturition and infant birth weight (IBW) was recorded.

RESULTS

OIL was significantly more in participants with mild and moderate periodontitis as compared to those with gingivitis in mid and late stages of pregnancy. Periodontal and systemic inflammatory parameters were positively correlated. A significant negative correlation was found between IBW and OIL (P = 0.006) and serum CRP (P < 0.001). The GI score (P = 0.039), BOP% (P = 0.023), serum CRP level (P < 0.001) and oral polymorphonuclear neutrophil (oPMN) count (P < 0.001) was significantly more in mothers delivering babies with low IBW. A multiple linear regression analysis showed that only oPMN (β = - 0.244, P = 0.021) and serum CRP (β = - 0.226, P = 0.019) were included in the best model (R²  = 0.12, F(3,152) = 7.15, P < 0.001) for significantly predicting the infant birth weight.

CONCLUSIONS

Poor maternal periodontal status, increased oral inflammatory load and increased systemic inflammation have an adverse effect on infant birth weight.

A review of T helper 17 cell-related cytokines in serum and saliva in periodontitis

Periodontitis is a chronic inflammatory disease with a complex underlying immunopathology. Cytokines, as molecular mediators of inflammation, play a role in all stages of disease progression. T helper 17 (Th17) cells are thought to play a role in periodontitis. Th17 cell development and maintenance requires a pro-inflammatory cytokine milieu, with many of the cytokines implicated in the pathogenesis of periodontitis. Serum and saliva are easily accessible biofluids which can represent the systemic and local environment to promote the development of Th17 cells. Here we review human clinical studies that investigate IL-1β, IL-4, IL-6, IL-10, IL-17A, IL-17F, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, IFN-γ, sCD40L and TNF-α in serum and saliva in periodontitis. We highlight their putative role in the pathogenesis of periodontitis and place them within a wider context of animal and other clinical studies.

Risk of preterm birth associated with maternal gingival inflammation and oral hygiene behaviours in rural Nepal: a community-based, prospective cohort study

OBJECTIVES

Observational studies have identified associations between periodontitis and adverse pregnancy outcomes, but randomised controlled trials evaluating the efficacy of periodontal therapy have yielded inconsistent results. Few studies have explored relationships between gingival inflammation and these outcomes or been conducted in rural, low-income communities, where confounding risk factors differ from other settings.

METHODS

We conducted a community-based, prospective cohort study with the aim of estimating associations between the extent of gingival inflammation in pregnant women and incidence of preterm birth in rural Nepal. Our primary exposure was gingival inflammation, defined as bleeding on probing (BOP) ≥10%, stratified by BOP <30% and BOP ≥30%. A secondary exposure, mild periodontitis, was defined as ≥2 interproximal sites with probing depth (PD) ≥4 mm (different teeth) or one site with PD ≥5 mm. Our primary outcome was preterm birth (<37 weeks gestation). We used Poisson regression to model this relationship, adjusting for potential confounders.

RESULTS

Of 1394 participants, 554 (39.7%) had gingival inflammation, 54 (3.9%) mild periodontitis and 197 (14.1%) delivered preterm. In the adjusted regression model, increasing extent of gingival inflammation was associated with a non-significant increase in risk of preterm birth (BOP ≥30% vs no BOP: adjusted relative risk (aRR) 1.37, 95% CI: 0.81 to 2.32). A secondary analysis, stratifying participants by when in pregnancy their oral health status was assessed, showed an association between gingival inflammation and preterm birth among women examined in their first trimester (BOP ≥30% vs no BOP: aRR 2.57, 95% CI: 1.11 to 5.95), but not later in pregnancy (BOP ≥30% vs no BOP: aRR 1.05, 95% CI: 0.52 to 2.11).

CONCLUSIONS

Gingival inflammation in women examined early in pregnancy and poor oral hygiene behaviours were risk factors for preterm birth. Future studies should evaluate community-based oral health interventions that specifically target gingival inflammation, delivered early in or before pregnancy, on preterm birth.

TRIAL REGISTRATION NUMBER

Nepal Oil Massage Study, NCT01177111.

Periodontal disease and adverse pregnancy outcomes

Periodontal diseases are considered not only to affect tooth-supporting tissues but also to have a cause-and-effect relationship with various systemic diseases and conditions, such as adverse pregnancy outcomes. Mechanistic studies provide strong evidence that periodontal pathogens can translocate from infected periodontium to the feto-placental unit and initiate a metastatic infection. However, the extent and mechanisms by which metastatic inflammation and injury contribute to adverse pregnancy outcomes still remain unclear. The presence of oral bacteria in the placenta of women with term gestation further complicates our understanding of the biology behind the role of periodontal pathogens in pregnancy outcomes. Epidemiological studies demonstrate many methodological inconsistencies and flaws that render comparisons difficult and conclusions insecure. Therefore, despite the fact that a number of prospective studies show a positive association between periodontal diseases and various adverse pregnancy outcomes, the evidence behind it is still weak. Future well-designed explanatory studies are necessary to verify this relationship and, if present, determine its magnitude. The majority of high-quality randomized controlled trials reveal that nonsurgical periodontal therapy during the second trimester of gestation does not improve pregnancy outcomes. From a biological standpoint, this can be partially explained by the fact that therapy rendered at the fourth to sixth months of pregnancy is too late to prevent placental colonization by periodontal pathogens and consequently incapable of affecting pathogen-induced injury at the feto-placental unit. Thus, interventions during the preconception period may be more meaningful. With the increase in our understanding on the potential association between periodontal disease and adverse pregnancy outcomes, it is clear that dental practitioners should provide periodontal treatment to pregnant women that is safe for both the mother and the unborn child. Although there is not enough evidence that the anti-infective therapy alters pregnancy outcomes, it improves health-promoting behavior and periodontal condition, which in turn advance general health and risk factor control.

The influence of nonsurgical periodontal therapy on the occurrence of adverse pregnancy outcomes: A systematic review of the current evidence

BACKGROUND AND OBJECTIVES

The poor maternal oral health in the pregnancy has an impact on the fetus through the oral-systemic link. Various studies have proven the relationship between poor maternal oral health and the occurrence of adverse pregnancy outcomes. Hence, periodontal therapy becomes indispensable during pregnancy. Previous systematic reviews and meta-analysis conducted to assess the influence of periodontal therapy on the occurrence of adverse pregnancy outcomes have shown inconsistent results. Hence, we conducted the present review to assess the influence of periodontal therapy on the occurrence of adverse pregnancy outcomes including the studies published till date.

MATERIALS AND METHODS

We searched for the relevant studies using the databases PUBMED, MEDLINE, CINAHL, and EMBASE on the randomized controlled trials evaluating the influence of periodontal treatment on adverse pregnancy outcomes from 2000 to 2018. Nineteen studies were considered for the present review based on the predetermined criteria. The risk of bias tool by Cochrane was used to evaluate the risk of bias among the studies.

RESULTS

Among the studies included for the present review, the occurrence of preterm birth among the pregnant mothers who received periodontal therapy ranged from 0% to 53.5%, while in the control group, the range was 6.38%-72%. The rate of LBW among the mothers treated for periodontal disease ranged from 0% to 36%, and in the control group, it varied from 1.15% to 53.9%.

CONCLUSION

With best possible evidence, it can be inferred that nonsurgical periodontal therapy is safe during pregnancy. Even though it does not completely avert the occurrence of adverse pregnancy outcomes, it can be recommended as a part of antenatal care.

Periodontal therapy for primary or secondary prevention of cardiovascular disease in people with periodontitis

BACKGROUND

There may be an association between periodontitis and cardiovascular disease (CVD); however, the evidence so far has been uncertain about whether periodontal therapy can help prevent CVD in people diagnosed with chronic periodontitis. This is the second update of a review originally published in 2014, and first updated in 2017. Although there is a new multidimensional staging and grading system for periodontitis, we have retained the label 'chronic periodontitis' in this version of the review since available studies are based on the previous classification system.

OBJECTIVES

To investigate the effects of periodontal therapy for primary or secondary prevention of CVD in people with chronic periodontitis.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the Cochrane Oral Health's Trials Register, CENTRAL, MEDLINE, Embase, and CINAHL, two trials registries, and the grey literature to September 2019. We placed no restrictions on the language or date of publication. We also searched the Chinese BioMedical Literature Database, the China National Knowledge Infrastructure, the VIP database, and Sciencepaper Online to August 2019.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared active periodontal therapy to no periodontal treatment or a different periodontal treatment. We included studies of participants with a diagnosis of chronic periodontitis, either with CVD (secondary prevention studies) or without CVD (primary prevention studies).

DATA COLLECTION AND ANALYSIS

Two review authors carried out the study identification, data extraction, and 'Risk of bias' assessment independently and in duplicate. They resolved any discrepancies by discussion, or with a third review author. We adopted a formal pilot-tested data extraction form, and used the Cochrane tool to assess the risk of bias in the studies. We used GRADE criteria to assess the certainty of the evidence.

MAIN RESULTS

We included two RCTs in the review. One study focused on the primary prevention of CVD, and the other addressed secondary prevention. We evaluated both as being at high risk of bias. Our primary outcomes of interest were death (all-cause and CVD-related) and all cardiovascular events, measured at one-year follow-up or longer. For primary prevention of CVD in participants with periodontitis and metabolic syndrome, one study (165 participants) provided very low-certainty evidence. There was only one death in the study; we were unable to determine whether scaling and root planning plus amoxicillin and metronidazole could reduce incidence of all-cause death (Peto odds ratio (OR) 7.48, 95% confidence interval (CI) 0.15 to 376.98), or all CVD-related death (Peto OR 7.48, 95% CI 0.15 to 376.98). We could not exclude the possibility that scaling and root planning plus amoxicillin and metronidazole could increase cardiovascular events (Peto OR 7.77, 95% CI 1.07 to 56.1) compared with supragingival scaling measured at 12-month follow-up. For secondary prevention of CVD, one pilot study randomised 303 participants to receive scaling and root planning plus oral hygiene instruction (periodontal treatment) or oral hygiene instruction plus a copy of radiographs and recommendation to follow-up with a dentist (community care). As cardiovascular events had been measured for different time periods of between 6 and 25 months, and only 37 participants were available with at least one-year follow-up, we did not consider the data to be sufficiently robust for inclusion in this review. The study did not evaluate all-cause death and all CVD-related death. We are unable to draw any conclusions about the effects of periodontal therapy on secondary prevention of CVD.

AUTHORS' CONCLUSIONS

For primary prevention of cardiovascular disease (CVD) in people diagnosed with periodontitis and metabolic syndrome, very low-certainty evidence was inconclusive about the effects of scaling and root planning plus antibiotics compared to supragingival scaling. There is no reliable evidence available regarding secondary prevention of CVD in people diagnosed with chronic periodontitis and CVD. Further trials are needed to reach conclusions about whether treatment for periodontal disease can help prevent occurrence or recurrence of CVD.

The connection between microbiome and schizophrenia

There has been an accumulation of knowledge about the human microbiome, some detailed investigations of the gastrointestinal microbiota and its functions, and the highlighting of complex interactions between the gut, the gut microbiota, and the central nervous system. That assumes the involvement of the microbiome in the pathogenesis of various CNS diseases, including schizophrenia. Given this information and the fact, that the gut microbiota is sensitive to internal and environmental influences, we have speculated that among the factors that influence the formation and composition of gut microbiota during life, possible key elements in the schizophrenia development chain are hidden where gut microbiota is a linking component. This article aims to describe and understand the developmental relationships between intestinal microbiota and the risk of developing schizophrenia.

Effect of periodontal treatment in pregnancy on perinatal outcomes: a systematic review and meta-analysis

OBJECTIVE

To assess the effect of periodontal treatment during pregnancy on maternal, fetal and neonatal outcomes.

METHODS

This is a systematic review and meta-analysis of randomized controlled trials that evaluated the effect of treatment of periodontal diseases on pregnancy outcomes. Primary outcome was perinatal mortality. Secondary outcomes were maternal and neonatal morbidity. Outcomes were pooled using fix-effect or random effects models and presented as risk ratio (RR), or mean difference (MD), and 95% confidence interval (CI).

RESULTS

Twenty randomized controlled trials involving 8171 participants were included in this study. Periodontal treatment during pregnancy was associated with significantly decreased risk of perinatal mortality [N = 5942; RR = 0.53 (0.30-0.93); p = .03; heterogeneity (I²) = 0%, Number needed to treat (NNT): 162]. Periodontal treatment during pregnancy reduced risks of preterm birth [N = 7335; RR = 0.78 (0.62-0.98); p = .03; I² = 72%, NNT = 37]. Periodontal treatment during pregnancy significantly increased birthweight (gram) [N = 4708; MD = 200.79 (63.34-337.24); p = .004; I² = 93%]. Periodontal treatment during pregnancy was not associated with preeclampsia, gestational diabetes, cesarean section, small for gestational age, or congenital malformations.

CONCLUSION

Periodontal treatment during pregnancy reduces the risks of perinatal mortality and preterm birth, and improves birth weight.

Non-Surgical Treatment of Periodontal Disease in a Pregnant Caucasian Women Population: Adverse Pregnancy Outcomes of a Randomized Clinical Trial

AIM

To analyze if non-surgical treatment of periodontitis in a pregnant Caucasian women population can reduce adverse pregnancy outcomes.

METHODS AND RESULTS

A parallel randomized clinical trial was designed and approved by the Ethical Committee of Sanitary Area Santiago-Lugo, Spain (registration number: 2016/451). Forty patients with periodontitis stage II grade B were randomly allocated to receive either comprehensive non-surgical periodontal therapy (test group; n = 20) or professional tooth cleaning (control group; n = 20) before 24 gestational weeks. Randomization was computer-generated by the statistic program Epidat v.4.1 and allocation was performed using sealed opaque envelopes. Clinical measurements and peripheral blood samples for biochemical variables were collected at baseline, in the middle of second trimester before non-surgical treatment, and in the third trimester. Microbiological samples were collected in the second and third trimester. A statistically significant reduction was verified in all clinical and microbiological parameters after periodontal treatment in the test group. No significant differences were observed for the rest of the variables, including preterm birth and/or low birth weight. No adverse events related to periodontal treatment were reported.

CONCLUSIONS

Non-surgical periodontal treatment in Caucasian patients with periodontitis stage II grade B did not significantly reduce the risk of adverse pregnancy outcomes.

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.

Population-Based Estimation of Dental Caries and Periodontal Disease Rates of Gravid and Recently Postpartum Women in Lilongwe, Malawi

Objectives  The objective of this study was to determine the rate of dental caries and periodontal disease among gravid and recently postpartum women at five delivery centers within and surrounding Lilongwe, Malawi. Study Design  We partnered with obstetric specialists, community health workers, and dentists to perform dental history interviews and dental examinations during the study period from December 2012 to May 2014. Dental examinations were performed according to World Health Organization standards to assess periodontal and oral health status. Results  Among the 387 gravid and recently postpartum women, the rate of dental caries was 69.3% and the rate of composite dental disease (caries and periodontal disease) was 76.7%. The majority (69.5%) of women examined had a decayed-missing-filled (DMF) index greater than or equal to one; the average DMF Index was 2.48. The majority of women had never seen a dentist (62.8%). However, most did perform oral hygiene, two or more times per day (90.2%); most women reported brushing with toothpaste (88.1%). Conclusion  When assessing this population for dental caries and periodontal disease, the rate of dental disease was high. Therefore, this may be an ideal setting to test for impactful interventions aimed at reducing caries and periodontal disease.

Down-regulated Treg cells in exacerbated periodontal disease during pregnancy

Pregnancy is a special period marked with complicated changes in various immune responses. Although pregnant women are prone to developing gingival inflammation, its immunological mechanism remains to be clarified. In a modified ligature-induced periodontal disease murine model, pregnant mice developed more severe alveolar bone loss. Using this model, we investigated the Treg responses during exacerbated periodontal disease in pregnant mice. We tested Treg-associated molecules in gingival tissues by quantitative real-time PCR and found decreased gingival expression of Foxp3, TGFβ, CTLA-4, and CD28 in pregnant mice after periodontal disease induction. We further confirmed that lower number of Treg cells were present in the cervical lymph nodes of pregnant periodontitis mice. Treg cells from the cervical lymph nodes of ligated pregnant mice and non-pregnant mice were tested for their suppressive function in vitro. We manifested that Treg suppressive function was also down-regulated in the pregnant mice. Additionally, we demonstrated that more inflammatory Th17 cells were present in the cervical lymph nodes of ligated pregnant mice. Therefore, impaired Treg development and function, together with upregulated Th17 response, may contribute to the exacerbated periodontal disease during pregnancy.

Dental caries experience and associated risk indicators among Palestinian pregnant women in the Jerusalem area: a cross-sectional study

BACKGROUND

This study described the dental caries experience of Palestinian pregnant women and examined its relationships to their oral health knowledge, beliefs, behavior, and access to dental care.

METHODS

Pregnant women receiving prenatal care at the Ministry of Health (MOH) centers in the Jerusalem Governorate were invited to participate in this study. Structured interviews were conducted to assess pregnant mothers' beliefs about oral health care and their oral hygiene practices. Screening for mothers' dental caries experience was carried out using the Decayed, Missing and Filled Teeth/Surfaces (DMFT/S) index. Univariate, bi-variate and multi-variable analysis were conducted to explain the high level of disease in this population.

RESULTS

A total of 152 pregnant women participated in this study. Mean DMFT in this sample was 15.5 ± 4.5 and an average DMFS of 31.8 ± 21. According the World Health Organization (WHO) criteria, 89% of our sample were categorized in the "Extremely High" dental caries experience. Fifty-eight percent of the DMFT scores among this sample were due to untreated dental decay, while 22% of the same DMFT scores demonstrated restorative care received by this sample. Bivariate analysis showed that mothers who completed a degree after high school had lower DMFT scores than mothers who did not (F = 4, n = 152, p = .024). In addition, mothers who believed they could lose a tooth just because they are pregnant had higher DMFT scores (t = - 4, n = 152, p = .037). The final model found that age, level of education, providers' advice on utilizing dental care during pregnancy, and the belief that a woman can lose a tooth just because she is pregnant explained 22% of the variation in DMFT scores.

CONCLUSIONS

Women in this study had a high prevalence of dental diseases and knew little about dental care during pregnancy. Faulty beliefs about dental care during pregnancy among women and health care providers were major factors in the high levels of disease.

GWAS for Interleukin-1β levels in gingival crevicular fluid identifies IL37 variants in periodontal inflammation

There is no agnostic GWAS evidence for the genetic control of IL-1β expression in periodontal disease. Here we report a GWAS for "high" gingival crevicular fluid IL-1β expression among 4910 European-American adults and identify association signals in the IL37 locus. rs3811046 at this locus (p = 3.3 × 10-22) is associated with severe chronic periodontitis (OR = 1.50; 95% CI = 1.12-2.00), 10-year incident tooth loss (≥3 teeth: RR = 1.33; 95% CI = 1.09-1.62) and aggressive periodontitis (OR = 1.12; 95% CI = 1.01-1.26) in an independent sample of 4927 German/Dutch adults. The minor allele at rs3811046 is associated with increased expression of IL-1β in periodontal tissue. In RAW macrophages, PBMCs and transgenic mice, the IL37 variant increases expression of IL-1β and IL-6, inducing more severe periodontal disease, while IL-37 protein production is impaired and shows reduced cleavage by caspase-1. A second variant in the IL37 locus (rs2708943, p = 4.2 × 10-7) associates with attenuated IL37 mRNA expression. Overall, we demonstrate that IL37 variants modulate the inflammatory cascade in periodontal disease.

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.

Personal Oral Infection Control, Low Birthweight, and Preterm Births in Appalachia West Virginia: A Cross-Sectional Study

INTRODUCTION

Appalachia West Virginia has a higher prevalence of preterm and low birthweight babies than the US national prevalence. Many factors have been studied which are known to influence preterm births and low birthweight babies. There are limited interventions that are available to decrease the likelihood of preterm and low birthweight babies; however oral health and personal oral infection control may be helpful. The purpose of this study was to evaluate the association of limited personal oral infection control among pregnant West Virginia Appalachian women and poor birth outcomes (preterm and low birthweight babies).

METHODS

A secondary data analysis of data from the West Virginia Healthy Start Helping Appalachian Parents and Infants (HAPI) Project from 2005 to 2016 was conducted. The researchers determined the odds ratio of personal oral infection control with a powered toothbrush (use of the brush fewer than 13 times per week versus use of the brush 13 or more times per week) on poor birth outcomes.

RESULTS

There were 845 women who completed the oral health program within the HAPI project. In unadjusted logistic regression, women who used the powered toothbrush and brushed less frequently had greater odds of poor birth outcomes than women who brushed more frequently (odds ratio of 2.07 [1.18, 3.62] P = 0.011 for low birthweight babies; and an odds ratio of 1.78 [1.04, 3.02] P = 0.034 for preterm birth). The results remained positive but were no longer significant in adjusted analysis.

CONCLUSION

There is a need to identify interventions that will benefit pregnant women so that their pregnancies result in healthy pregnancy outcomes.

Interaction between stress, cytokines, and salivary cortisol in pregnant and non-pregnant women with gingivitis

OBJECTIVES

The aim of this study was to compare the effects of periodontal treatment on the inflammatory markers in gingival crevicular fluid and the concentration of salivary cortisol between non-pregnant and pregnant women with gingivitis.

MATERIALS AND METHODS

This study included 30 non-pregnant women (mean age 27.93 ± 6.61 years) and 30 pregnant women (mean age 28.93 ± 4.04 years). Each participant presented with the clinical symptoms of generalized, moderate-to-severe gingivitis. Saliva samples were collected by using the spitting method, and gingival crevicular fluid (GCF) samples were collected by using the intrasulcular method at baseline and after 3 weeks. Non-surgical periodontal treatment (NPT) comprising scaling and oral hygiene instruction was administered after sample collection. The interleukin-6 and interleukin-10 levels in GCF and salivary cortisol concentrations were determined with using enzyme-linked immunosorbent assay.

RESULTS

The pregnant women exhibited significantly deeper pockets (p < 0.05) and greater gingival inflammation (p < 0.05) than the non-pregnant women after periodontal therapy. Moreover, the levels of interleukin-6 in the GCF were significantly higher in the pregnant women compared to the non-pregnant women after periodontal therapy: 17.73 ± 9.82 pg per site and 8.08 ± 4.51 pg per site, respectively, p < 0.05. No differences in the levels of interleukin-10 were observed. The pregnant women also exhibited higher cortisol concentration in the saliva after periodontal therapy, compared to the non-pregnant women, while the levels of stress (as seen on the perceived stress scale-10) were similar in both groups.

CONCLUSIONS

Although non-surgical periodontal therapy may reduce the clinical parameters of gingivitis, increasing levels of stress in pregnancy may reduce the individual's response to it. However, further studies are necessary to substantiate these early findings.

CLINICAL RELEVANCE

Psychosocial stress may increase the risk of periodontal disease by altering the behavioral and immune responses of the individual. Therefore, the levels of stress should be taken into consideration in order to increase the efficacy of periodontal therapy in pregnant patients.

Periodontal therapy for the management of cardiovascular disease in patients with chronic periodontitis

BACKGROUND

There is an association between chronic periodontitis and cardiovascular disease (CVD). However, it is not known whether periodontal therapy could prevent or manage CVD in patients with chronic periodontitis.

OBJECTIVES

The objective of this systematic review was to investigate the effects of periodontal therapy in preventing the occurrence of, and management or recurrence of, CVD in patients with chronic periodontitis.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 31 August 2017), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2017, Issue 7), MEDLINE Ovid (1946 to 31 August 2017), Embase Ovid (1980 to 31 August 2017) and the Cumulative Index to Nursing and Allied Health Literature (CINAHL EBSCO) (1937 to 31 August 2017) . The US National Institutes of Health Trials Registry (ClinicalTrials.gov), the World Health Organization International Clinical Trials Registry Platform and Open Grey were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.We also searched the Chinese BioMedical Literature Database (1978 to 27 August 2017), the China National Knowledge Infrastructure (1994 to 27 August 2017), the VIP database (1989 to 27 August 2017) and Sciencepaper Online (2003 to 27 August 2017).

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs were considered eligible. Studies were selected if they included patients with a diagnosis of chronic periodontitis and previous CVD (secondary prevention studies) or no CVD (primary prevention studies); patients in the intervention group received active periodontal therapy compared to maintenance therapy, no periodontal treatment or another kind of periodontal treatment in the control group.

DATA COLLECTION AND ANALYSIS

Two review authors carried out the study identification, data extraction and risk of bias assessment independently and in duplicate. Any discrepancies between the two authors were resolved by discussion or with a third review author. A formal pilot-tested data extraction form was adopted for the data extraction, and the Cochrane tool for risk of bias assessment was used for the critical appraisal of the literature.

MAIN RESULTS

No studies were identified that assessed primary prevention of CVD in people with periodontitis. One study involving 303 participants with ≥ 50% blockage of one coronary artery or a coronary event within three years, but not the three months prior, was included. The study was at high risk of bias due to deviation from the protocol treatment allocation and lack of follow-up data. The trial compared scaling and root planing (SRP) with community care for a follow-up period of six to 25 months. No data on deaths (all-cause or CVD-related) were reported. There was insufficient evidence to determine the effect of SRP and community care in reducing the risk of CVD recurrence in patients with chronic periodontitis (risk ratio (RR) 0.72; 95% confidence interval (CI) 0.23 to 2.22; very low quality evidence). The effects of SRP compared with community care on high-sensitivity C-reactive protein (hs-CRP) (mean difference (MD) 0.62; -1.45 to 2.69), the number of patients with high hs-CRP (RR 0.77; 95% CI 0.32 to 1.85) and adverse events (RR 9.06; 95% CI 0.49 to 166.82) were also not statistically significant. The study did not assess modifiable cardiovascular risk factors, other blood test results, heart function parameters or revascularisation procedures.

AUTHORS' CONCLUSIONS

We found very low quality evidence that was insufficient to support or refute whether periodontal therapy can prevent the recurrence of CVD in the long term in patients with chronic periodontitis. No evidence on primary prevention was found.

An Umbrella Review Exploring the Effect of Periodontal Treatment in Pregnant Women on the Frequency of Adverse Obstetric Outcomes

OBJECTIVE

In the recent years, efforts have been made to reduce epidemiologic indicators of periodontal disease in pregnant women. This umbrella review aims to analyze the systematic reviews/meta-analyses investigating the effect of periodontal therapy in pregnant women on the frequency of obstetric complications (low birth weight, preterm delivery, and preeclampsia) and to identify the gaps in the scientific literature.

METHODS

A systematic review of systematic reviews with and without meta-analysis of intervention studies was conducted. Quality evaluation and qualitative analysis of the reviews were performed.

RESULTS

A total of 223 articles were obtained, and 18 of them were included in the analysis, 13 articles included meta-analysis, where 11 were of high quality and 7 of medium quality according to the Assessing the Methodological Quality of Systematic Reviews (AMSTAR) guide. These systematic reviews/meta-analyses included a total of 19 studies (17 randomized clinical trials). Descriptive systematic reviews showed that periodontal therapy has positive effects on reducing the frequency of adverse pregnancy outcomes. In systematic reviews with meta-analysis, overall effect estimators were not significant, although a reduction in the incidence of obstetric complications was observed. Subgroup analysis resulted in significant effects, depending on sociodemographic conditions.

CONCLUSIONS

Differential findings are not enough to demonstrate that there is a significant reduction in the frequency of adverse pregnancy outcomes in pregnant women receiving periodontal therapy. Possible explanations are related to factors such as the type of studies analyzed, indicator of obstetric complication considered, and specific variables included in the analysis. Many systematic reviews did not address publication bias and did identify gaps in knowledge that require further clarification.

Effect of intra-pregnancy nonsurgical periodontal therapy on inflammatory biomarkers and adverse pregnancy outcomes: a systematic review with meta-analysis

BACKGROUND

The aim of this systematic review with meta-analysis was to analyze the effects of intra-pregnancy nonsurgical periodontal therapy on periodontal inflammatory biomarkers and adverse pregnancy outcomes.

METHODS

On June 5, 2017, we searched PubMed, Cochrane, SCOPUS, Web of Science, LILACS, ProQuest, Open Grey, and Google Scholar databases. Randomized clinical trials in which pregnant women with chronic periodontitis underwent nonsurgical periodontal therapy, compared with an untreated group, tested for inflammatory biomarkers, and followed till delivery were included. Primary outcomes were preterm birth, low birth weight, and preeclampsia. Meta-analysis was performed with 5.3.5 version of Review Manager software.

RESULTS

We found 565 references in the databases, 326 after duplicates removal, 28 met criteria for full text reading, and 4 met eligibility criteria for quantitative and qualitative synthesis. Intra-pregnancy nonsurgical periodontal therapy improved periodontal clinical parameters (periodontal pocket depth, clinical attachment level, and bleeding on probing) and reduced biomarker level from gingival crevicular fluid (GCF), and some from blood serum; however, it did not influence biomarker level from umbilical cord blood. Meta-analysis showed tendency for reduction of the risk of preterm birth before 37 weeks for treated group (risk ratio (RR) = 0.54, 95% CI 0.38-0.77; p = 0.0007; inconsistency indexes (I2) 32%) but did not show any difference for low birth weight occurrence (RR = 0.78, 95%CI 0.50-1.21; p = 0.27; I2 41%). No included study considered preeclampsia as a gestational outcome.

CONCLUSIONS

These results demonstrated that the intra-pregnancy nonsurgical periodontal therapy decreased periodontal inflammatory biomarker levels from gingival crevicular fluid and some from serum blood, with no influence on inflammatory biomarker level from cord blood, and it did not consistently reduce adverse gestational adverse outcome occurrence.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42015027750.

Treating periodontal disease for preventing adverse birth outcomes in pregnant women

BACKGROUND

Periodontal disease has been linked with a number of conditions, such as cardiovascular disease, stroke, diabetes and adverse pregnancy outcomes, all likely through systemic inflammatory pathways. It is common in women of reproductive age and gum conditions tend to worsen during pregnancy. Some evidence from observational studies suggests that periodontal intervention may reduce adverse pregnancy outcomes. There is need for a comprehensive Cochrane review of randomised trials to assess the effect of periodontal treatment on perinatal and maternal health.

OBJECTIVES

To assess the effects of treating periodontal disease in pregnant women in order to prevent or reduce perinatal and maternal morbidity and mortality.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 6 October 2016), Cochrane Pregnancy and Childbirth's Trials Register (to 7 October 2016), the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 9) in the Cochrane Library, MEDLINE Ovid (1946 to 6 October 2016), Embase Ovid (1980 to 6 October 2016), and LILACS BIREME Virtual Health Library (Latin American and Caribbean Health Science Information database; 1982 to 6 October 2016). ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials on 6 October 2016. We placed no restrictions on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) investigating the effects of periodontal treatment in preventing or reducing perinatal and maternal morbidity and mortality. We excluded studies where obstetric outcomes were not reported.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles and abstracts and extracted data using a prepiloted data extraction form. Missing data were obtained by contacting authors and risk of bias was assessed using Cochrane's 'Risk of bias' tool. Where appropriate, results of comparable trials were pooled and expressed as risk ratios (RR) or mean differences (MD) with 95% confidence intervals (CI) . The random-effects model was used for pooling except where there was an insufficient number of studies. We assessed the quality of the evidence using GRADE.

MAIN RESULTS

There were 15 RCTs (n = 7161 participants) meeting our inclusion criteria. All the included studies were at high risk of bias mostly due to lack of blinding and imbalance in baseline characteristics of participants. The studies recruited pregnant women from prenatal care facilities who had periodontitis (14 studies) or gingivitis (1 study).The two main comparisons were: periodontal treatment versus no treatment during pregnancy and periodontal treatment versus alternative periodontal treatment. The head-to-head comparison between periodontal treatments assessed a more intensive treatment versus a less intensive one.Eleven studies compared periodontal treatment with no treatment during pregnancy. The meta-analysis shows no clear difference in preterm birth < 37 weeks (RR 0.87, 95% CI 0.70 to 1.10; 5671 participants; 11 studies; low-quality evidence) between periodontal treatment and no treatment. There is low-quality evidence that periodontal treatment may reduce low birth weight < 2500 g (9.70% with periodontal treatment versus 12.60% without treatment; RR 0.67, 95% CI 0.48 to 0.95; 3470 participants; 7 studies).It is unclear whether periodontal treatment leads to a difference in preterm birth < 35 weeks (RR 1.19, 95% CI 0.81 to 1.76; 2557 participants; 2 studies; ) and < 32 weeks (RR 1.35, 95% CI 0.78 to 2.32; 2755 participants; 3 studies), low birth weight < 1500 g (RR 0.80, 95% CI 0.38 to 1.70; 2550 participants; 2 studies), perinatal mortality (including fetal and neonatal deaths up to the first 28 days after birth) (RR 0.85, 95% CI 0.51 to 1.43; 5320 participants; 7 studies; very low-quality evidence), and pre-eclampsia (RR 1.10, 95% CI 0.74 to 1.62; 2946 participants; 3 studies; very low-quality evidence). There is no evidence of a difference in small for gestational age (RR 0.97, 95% CI 0.81 to 1.16; 3610 participants; 3 studies; low-quality evidence) when periodontal treatment is compared with no treatment.Four studies compared periodontal treatment with alternative periodontal treatment. Data pooling was not possible due to clinical heterogeneity. The outcomes reported were preterm birth < 37 weeks, preterm birth < 35 weeks, birth weight < 2500 g, birth weight < 1500 g and perinatal mortality (very low-quality evidence). It is unclear whether there is a difference in < 37 weeks, preterm birth < 35 weeks, birth weight < 2500 g, birth weight < 1500 g and perinatal mortality when different periodontal treatments are compared because the quality of evidence is very low.Maternal mortality and adverse effects of the intervention did not occur in any of the studies that reported on either of the outcomes.

AUTHORS' CONCLUSIONS

It is not clear if periodontal treatment during pregnancy has an impact on preterm birth (low-quality evidence). There is low-quality evidence that periodontal treatment may reduce low birth weight (< 2500 g), however, our confidence in the effect estimate is limited. There is insufficient evidence to determine which periodontal treatment is better in preventing adverse obstetric outcomes. Future research should aim to report periodontal outcomes alongside obstetric outcomes.

Common Polymorphisms in IFI16 and AIM2 Genes Are Associated With Periodontal Disease

BACKGROUND

The single nucleotide polymorphism (SNP) context of a previously identified periodontitis-associated locus is investigated, and its association with microbial, biologic, and periodontal disease clinical parameters is examined.

METHODS

A 200-kb spanning region of 1q12 previously highlighted in a genome-wide association scan among 4,766 European American individuals (SNP rs1633266) was annotated. Two haplotype blocks were selected. Association of these polymorphisms with data on microbial plaque composition, gingival crevicular fluid (GCF)-interleukin (IL)-1β levels, and clinical parameters of periodontal disease were examined. Descriptive analysis of IFI16 and AIM2 protein expression in gingival tissues from healthy individuals (n = 2) and individuals with chronic periodontitis (n = 2) was done via immunohistochemistry.

RESULTS

The highlighted locus is a 100-kb region containing the interferon γ-inducible protein 16 (IFI16) and absent in melanoma 2 (AIM2) genes. Two haplotype blocks, rs6940 and rs1057028, were significantly associated with increased extent bleeding on probing and levels of microorganisms Porphyromonas gingivalis, Tannerella forsythia, and Campylobacter rectus (P ≤0.05). Haplotype block rs1057028 was also significantly associated with pathogens Fusobacterium nucleatum and Aggregatibacter actinomycetemcomitans, increased GCF-IL-1β levels, and extent of probing depth ≥4 mm (P ≤0.05). Prevalence of severe periodontitis (biofilm-gingival interface P3 classification) was positively associated with haplotype block rs1057028. Similar trends were observed for haplotype block rs1057028. IFI16 and AIM2 protein expression was observed in multiple cell types of gingival tissues, including inflammatory cells.

CONCLUSION

This study found IFI16 and AIM2 SNPs associated with higher levels of periodontal microorganisms and an increased percentage of periodontal disease clinical parameters, suggesting the need for functional studies and additional fine-mapping of variants in the 1q12-locus.

From focal sepsis to periodontal medicine: a century of exploring the role of the oral microbiome in systemic disease

The oral microbiome is established within a few minutes after birth and consists of stable multi-species communities that engage in a dynamic equilibrium with the host immune system. Dental caries, endodontic infections and periodontal diseases are bacterially driven diseases that are caused by dysbiotic microbiomes. Over a century ago, the focal infection theory implicated these infections in the aetiology of several systemic diseases, ranging from arthritis to neurodegenerative diseases. However, a lack of concrete evidence, combined with the urgency with which clinicians embraced this approach without regard for appropriate case selection, led to its demise within 30 years. In the last decade of the 20th century, the concept of periodontal medicine was introduced to explain the correlations that were being observed between periodontitis and cardiovascular disease, rheumatoid arthritis, Alzheimer's disease, pulmonary disease, pre-term delivery of low birth weight infants and metabolic disease. It was proposed that periodontal pathobionts played a causal role in the initiating or exacerbating certain diseases either by direct invasion or by stimulating a florid immune-inflammatory response that extended into the systemic circulation. This review will examine the strength of current evidence in establishing a causal link between oral pathobionts and systemic disease.