Periodontal disease treatment and risk of preterm birth: a systematic review and meta-analysis

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.

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.

Adverse Pregnancy Outcomes and Maternal Periodontal Disease: An Overview on Meta-Analytic and Methodological Quality

This umbrella review aims to appraise the methodological quality and strength of evidence on the association between maternal periodontitis and adverse pregnancy outcomes (APOs). PubMed, CENTRAL, Web-of-Science, LILACS, and Clinical Trials were searched until February 2023, without date or language restrictions. Two authors independently screened studies, extracted data, performed the risk-of-bias analysis, and estimated the meta-analytic strengths and validity and the fail-safe number (FSN). A total of 43 SRs were identified, of which 34 conducted meta-analyses. Of the 28 APOs, periodontitis had a strong association with preterm birth (PTB), low birth weight (LBW), and gestational diabetes mellitus (GDM), PTB and LBW showed all levels of strength, and pre-eclampsia showed only suggestive and weak strength. Regarding the consistency of the significant estimates, only 8.7% were likely to change in the future. The impact of periodontal treatment on APOs was examined in 15 SRs, 11 of which conducted meta-analyses. Forty-one meta-analyses were included and showed that periodontal treatment did not have a strong association with APOs, although PTB revealed all levels of strength and LBW showed only suggestive and weak evidence. Strong and highly suggestive evidence from observational studies supports an association of periodontitis with a higher risk of PTB, LBW, GDM, and pre-eclampsia. The effect of periodontal treatment on the prevention of APOs is still uncertain and requires future studies to draw definitive and robust conclusions.

The Potential Association Between Periodontal Diseases and Adverse Pregnancy Outcomes in Pregnant Women: A Systematic Review of Randomized Clinical Trials

Preceding studies have demonstrated that periodontitis might increase the liability of adverse pregnancy outcomes such as preterm birth, preeclampsia, low birth weight, and perinatal fatality in pregnant women. Nonetheless, there is no convincing testimony that periodontitis is related directly to adverse pregnancy outcomes in pregnant women. This systematic review intended to assess and review all the available randomized clinical trials that concentrated on the association between periodontal diseases and adverse pregnancy outcomes, and the impact of periodontal disease therapy on adverse pregnancy outcomes. The databases like Scopus, PubMed, Google Scholar, and Web of Science were consumed to explore relevant and suitable studies after adopting the inclusion and exclusion criteria. The search included articles with no time restrictions and certain keywords were utilized in the databases. The investigation was done through four independent reviewers employing the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Twenty-three studies fulfilled the exclusion and inclusion criteria and were used and included in this systematic review. The above-mentioned studies assessed the association between periodontal diseases and adverse pregnancy outcomes and the effect of periodontal disease treatment in reducing the influence of adverse pregnancy outcomes. This systematic review revealed that there is a relationship between periodontitis and adverse pregnancy outcomes, and periodontal treatment has a reducing impact on adverse pregnancy outcomes in pregnant women with periodontitis. Prospect studies are warranted to investigate the relationship between periodontitis and different adverse pregnancy outcomes and to decide the best type and the most effective therapy to treat periodontitis in pregnant women.

Interventions for the prevention of spontaneous preterm birth: a scoping review of systematic reviews

BACKGROUND

Globally, 11% of babies are born preterm each year. Preterm birth (PTB) is a leading cause of neonatal death and under-five mortality and morbidity, with lifelong sequelae in those who survive. PTB disproportionately impacts low/middle-income countries (LMICs) where the burden is highest.

OBJECTIVES

This scoping review sought to the evidence for interventions that reduce the risk of PTB, focusing on the evidence from LMICs and describing how context is considered in evidence synthesis.

DESIGN

We conducted a scoping review, to describe this wide topic area. We searched five electronic databases (2009-2020) and contacted experts to identify relevant systematic reviews of interventions to reduce the risk of PTB. We included published systematic reviews that examined the effectiveness of interventions and their effect on reducing the risk of PTB. Data were extracted and is described narratively.

RESULTS

139 published systematic reviews were included in the review. Interventions were categorised as primary or secondary. The interventions where the results showed a greater effect size and consistency across review findings included treatment of syphilis and vaginal candidiasis, vitamin D supplementation and cervical cerclage. Included in the 139 reviews were 1372 unique primary source studies. 28% primary studies were undertaken in LMIC contexts and only 4.5% undertaken in a low-income country (LIC) Only 10.8% of the reviews sought to explore the impact of context on findings, and 19.4% reviews did not report the settings or the primary studies.

CONCLUSION

This scoping review highlights the lack of research evidence derived from contexts where the burden of PTB globally is greatest. The lack of rigour in addressing contextual applicability within systematic review methods is also highlighted. This presents a risk of inappropriate and unsafe recommendations for practice within these contexts. It also highlights a need for primary research, developing and testing interventions in LIC settings.

Maternal risk factors for low birth weight infants: A nested case-control study of rural areas in Kurdistan (western of Iran)

Infant mortality is among the most important indicators of health and development in global communities. One of the causes of neonatal mortality is low birth weight. This study aims at evaluating the risk factors for LBW in infants. This study was carried out using a nested case-control study in rural areas of Kurdistan province in Western Iran in 2015. The selection of case and control groups was based on the nesting using the risk set sampling approach. In total, 182 and 364 subjects were selected for the case group and the control group respectively. Data analysis was performed using the Stata-12 software with the point and spatial estimation of OR using the conditional logistic regression method. The multivariate logistic regression analysis performed shows that the maternal gestational age, the mother’s health history during pregnancy, any medication abuses by the mother, any mental stress during pregnancy, are LBW risk factors (P < 0.05). Prevention of LBW is possible by identifying effective factors and performing appropriate interventions in infants with low birth weight.

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.

Effect of per Capita Income on the Relationship between Periodontal Disease during Pregnancy and the Risk of Preterm Birth and Low Birth Weight Newborn. Systematic Review and Meta-Analysis

This work analyzed the available evidence in the scientific literature about the risk of preterm birth and/or giving birth to low birth weight newborns in pregnant women with periodontal disease. A systematic search was carried out in three databases for observational cohort studies that related periodontal disease in pregnant women with the risk of preterm delivery and/or low birth weight, and that gave their results in relative risk (RR) values. Eleven articles were found, meeting the inclusion criteria. Statistically significant values were obtained regarding the risk of preterm birth in pregnant women with periodontitis (RR = 1.67 (1.17-2.38), 95% confidence interval (CI)), and low birth weight (RR = 2.53 (1.61-3.98) 95% CI). When a meta-regression was carried out to relate these results to the income level of each country, statistically significant results were also obtained; on the one hand, for preterm birth, a RR = 1.8 (1.43-2.27) 95% CI was obtained and, on the other hand, for low birth weight, RR = 2.9 (1.98-4.26) 95% CI. A statistically significant association of periodontitis, and the two childbirth complications studied was found, when studying the association between these results and the country's per capita income level. However, more studies and clinical trials are needed in this regard to confirm the conclusions obtained.

Porphyromonas gingivalis and adverse pregnancy outcomes: a review on its intricate pathogenic mechanisms

Porphyromonas gingivalis (P. gingivalis), a Gram-negative facultative anaerobe of the oral cavity, is associated with the onset of various adverse pregnancy outcomes. P. gingivalis is linked with the development of preeclampsia, preterm labour, spontaneous abortion, gestational diabetes, foetal growth restriction, and misconception. The unique virulence factors, surface adhesions, enzymes of P. gingivalis can directly injure and alter the morphology, microbiome the foetal and maternal tissues. P. gingivalis can even exaggerate the production of cytokines, free radicals and acute-phase proteins in the uterine compartment that increases the risk of myometrial contraction and onset of preterm labour. Although evidence confirms the presence of P. gingivalis in the amniotic fluid and placenta of women with poor pregnancy outcomes, the intricate molecular mechanisms by which P. gingivalis initiates various antenatal and postnatal maternal and foetal complications are not well explained in the literature. Therefore, the present review aims to comprehensively summarise and highlight the recent and unique molecular pathogenic mechanisms of P. gingivalis associated with adverse pregnancy outcomes.

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.

Periodontal diseases and adverse pregnancy outcomes

From last decade of the 20th century, numerous epidemiological studies and intervention trials have attempted to prove the relationships between maternal periodontal diseases and adverse pregnancy outcomes (APO). Periodontal diseases are considered a risk factor for APO, including preterm birth, fetal growth restriction, low birthweight, pre-eclampsia and gestational diabetes. However, the efficacy of periodontal treatment during pregnancy is controversial. Two pathogenic mechanisms might explain the potential effect of periodontal diseases on pregnancy outcomes. First, periodontal bacteria originating in the gingival biofilm directly affect the feto-placental unit subsequent to bacteremia. Second, inflammatory mediators secreted by the subgingival inflammatory site are carried to the feto-placental unit, where they then cause an inflammatory response. To elucidate these mechanisms, many researchers have been investigating the use of experimental animal models and in vitro models. In the present review, we summarize the current literature on the relationship between periodontal diseases and APO from epidemiological studies, animal models studies and in vitro studies, and speculate on the possible mechanism of periodontal diseases affecting pregnancy outcomes.

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.

Role of Maternal Periodontitis in Preterm Birth

In the last two decades, many studies have focused on whether periodontitis is a risk factor for preterm birth (PTB). However, both epidemiological investigation and intervention trials have reached contradictory results from different studies. What explains the different findings, and how should future studies be conducted to better assess this risk factor? This article reviews recent epidemiological, animal, and in vitro studies as well as intervention trials that evaluate the link between periodontitis and PTB. Periodontitis may act as a distant reservoir of microbes and inflammatory mediators and contribute to the induction of PTB. Animal studies revealed that maternal infections with periodontal pathogens increase levels of circulating IL-1β, IL-6, IL-8, IL-17, and TNF-α and induce PTB. In vitro models showed that periodontal pathogens/byproducts induce COX-2, IL-8, IFN-γ, and TNF-α secretion and/or apoptosis in placental tissues/cells. The effectiveness of periodontal treatment to prevent PTB is influenced by the diagnostic criteria of periodontitis, microbial community composition, severity of periodontitis, treatment strategy, treatment efficiency, and the period of treatment during pregnancy. Although intervention trials reported contradictory results, oral health maintenance is an important part of preventive care that is both effective and safe throughout pregnancy and should be supported before and during pregnancy. As contradictory epidemiological and intervention studies continue to be published, two new ideas are proposed here: (1) severe and/or generalized periodontitis promotes PTB and (2) periodontitis only promotes PTB for pregnant women who are young or HIV-infected or have preeclampsia, pre-pregnancy obesity, or susceptible genotypes.

Planting the seed: Origins, composition, and postnatal health significance of the fetal gastrointestinal microbiota

It has long been assumed that establishment of the fetal microbiome commences with the birthing process. However, recent studies have found bacterial DNA in umbilical cord blood, placenta, amniotic fluid, meconium, and fetal membranes in healthy normal pregnancies, leading to suggestions that the seeding of the fetal microbiome may commence in utero long before delivery. The origins of the microbiota of the fetal gastrointestinal (GI) tract have not yet been conclusively determined, although bacterial translocation from the maternal circulation, or ascension from the vagina, are both likely to be contributing pathways. Mother-to-child efflux of bacteria during pregnancy has the potential to markedly influence postnatal health, as the composition of gut microbiota determines production of important metabolites which are absorbed systemically and which modify immune function and development. Hence, the importance of understanding the colonization of the fetal GI microbiome is becoming clear, although few studies have investigated the origins, dynamics, and timing of the fetal microbiome. This is the topic of this review. By gaining a deeper understanding of the mechanisms underpinning fetal microbiome seeding, strategies may be developed to optimize fetal immune development and reduce the risk of adverse health and developmental outcomes.

Periodontitis, cardiovascular disease and pregnancy outcome--focal infection revisited?

Over the last two decades there has been a renewed interest around the possible effects of periodontal disease on both cardiovascular health and pregnancy outcome (among other diseases), a topic which has interested science for hundreds of years. These have led to a range of studies, workshops and consensus documents being published, with corresponding coverage in general and professional media. In this article the authors summarise the history and supporting theories behind such associations, whether clinical studies have been able to confirm these and what this might mean for general practitioners who are questioned on this topic by patients.

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.

Exploring preterm birth as a polymicrobial disease: an overview of the uterine microbiome

Infection is a leading cause of preterm birth (PTB). A focus of many studies over the past decade has been to characterize microorganisms present in the uterine cavity and document any association with negative pregnancy outcome. A range of techniques have been used to achieve this, including microbiological culture and targeted polymerase chain reaction assays, and more recently, microbiome-level analyses involving either conserved, phylogenetically informative genes such as the bacterial 16S rRNA gene or whole shotgun metagenomic sequencing. These studies have contributed vast amounts of data toward characterization of the uterine microbiome, specifically that present in the amniotic fluid, fetal membranes, and placenta. However, an overwhelming emphasis has been placed on the bacterial microbiome, with far less data produced on the viral and fungal/yeast microbiomes. With numerous studies now referring to PTB as a polymicrobial condition, there is the need to investigate the role of viruses and fungi/yeasts in more detail and in particular, look for associations between colonization with these microorganisms and bacteria in the same samples. Although the major pathway by which microorganisms are believed to colonize the uterine cavity is vertical ascension from the vagina, numerous studies are now emerging suggesting hematogenous transfer of oral microbiota to the uterine cavity. Evidence of this has been produced in mouse models and although DNA-based evidence in humans appears convincing in some aspects, use of methodologies that only detect viable cells as opposed to lysed cells and extracellular DNA are needed to clarify this. Such techniques as RNA analyses and viability polymerase chain reaction are likely to play key roles in the clinical translation of future microbiome-based data, particularly in confined environments such as the uterus, as detection of viable cells plays a key role in diagnosis and treatment of infection.

Correlação entre saúde periodontal e idade gestacional

INTRODUÇÃO: O baixo peso de recém-nascidos (RN) é considerado um problema de saúde pública e, geralmente, é associado à prematuridade. A etiologia do parto prematuro é bastante complexa e, frequentemente, está relacionada a vários fatores. Diversas teorias têm correlacionado a saúde periodontal de gestantes com o nascimento de bebês prematuros (idade gestacional) e/ou com baixo peso ao nascer. OBJETIVO: O objetivo do presente estudo foi avaliar a possível correlação de saúde periodontal com idade gestacional e/ou com nascimento de bebês com baixo peso. MATERIAL E MÉTODO: Estudo observacional longitudinal prospectivo com gestantes que foram atendidas em um projeto de extensão da Universidade Federal do Piauí - Programa Preventivo para Gestantes e Bebês - PPGB. A coleta dos dados foi estruturada em dois momentos: 1º- Preenchimento de ficha contendo dados relativos à saúde geral e exame periodontal completo, e 2º- Coleta de dados referentes a tipo de parto, duração da gestação, peso e condição de saúde do bebê. RESULTADO: De 62 gestantes atendidas, 43 participaram do segundo momento do estudo. Ocorreu uma predominância de gestantes com idade entre 25 e 35 anos (55,81%). O índice de sangramento gengival variou de 1,19% a 92,50%. A média do peso dos bebês foi 3.365,33 g e do tempo gestacional foi 39,33 semanas. CONCLUSÃO: Os resultados deste estudo não deram suporte à hipótese de que a doença periodontal está associada à idade gestacional.