Relationship between periodontal disease in pregnant women and the nutritional condition of their newborns

P. gingivalis-Infected Macrophage Extracellular Vesicles Cause Adverse Pregnancy Outcomes

Periodontitis is a chronic inflammatory disease triggered by oral bacterial infection, with the bacterium Porphyromonas gingivalis being a major causative agent. The association between periodontitis and various systemic diseases has been demonstrated. Recent research has also highlighted the relationship between the aggravation of maternal periodontitis and adverse pregnancy outcomes such as preterm birth and low birth weight. However, the molecular mechanisms underlying how factors from periodontitis influence pregnancy and fetal development remain unclear. Extracellular vesicles (EVs) are nano-sized spherical particles secreted into the tissue microenvironment by various types of cells. EVs have garnered interest in recent years due to their role in intercellular communication. In the present study, we investigated whether EVs derived from P. gingivalis-infected macrophages (Pg-inf EVs) reach the feto-placental unit and influence fetal development. Through a series of in vivo experiments in mice, we demonstrated that Pg-inf EVs translocated to the feto-placental unit and impaired fetal development in size and weight. Histological analysis revealed disoriented blood vessel alignment and impaired angiogenesis in the placentas of Pg-inf EV-injected groups, indicative of compromised placental function. Proteome analysis revealed a significant decrease in Vegfr1 expression in the placentas of the experimental group. Moreover, Pg-inf EVs reduced VEGFR1 expression in cultured human vascular endothelial cells, highlighting a potential molecular mechanism through which these EVs exert their effects on placental angiogenesis. This is the first study to reveal a novel pathway in which oral bacteria-infected macrophage EVs in maternal periodontitis affect pregnancy via the feto-placental unit.

Pain, anxiety, and catastrophizing among pregnant women with dental pain, undergoing root canal treatment

This prospective study aims to evaluate dental pain, anxiety, and catastrophizing levels in pregnant women undergoing root canal treatment. Sixty pregnant and non-pregnant women presenting dental pain and an indication for root canal treatment were included in the study. Dental anxiety and catastrophizing were investigated using validated questionnaires. The endodontic intervention was performed, and a numerical scale measured preoperative and postoperative dental pain. The results were analyzed using STATA software 12.0. Unadjusted analyses assessed the association between pregnancy and pain, anxiety, and catastrophizing levels. Multiple linear regression models using 'forward stepwise' entry procedures were used to assess the independent effects of variables on pain scores. The significance level was set at 0.05. Initially, most patients experienced intense dental pain. The levels of dental pain, dental anxiety, and catastrophizing did not differ between pregnant and non-pregnant women. Logistic regression showed that postoperative pain was associated with irreversible pulpitis diagnosis (OR = 4.78; 95%CI 1.55-13.55) and high catastrophizing levels (OR = 1.96; 95%CI 1.01-3.84). Preoperative and postoperative pain rates and anxiety and catastrophizing were similar between pregnant and non-pregnant patients. Postoperative pain was associated with irreversible pulpitis diagnosis and high catastrophizing levels. The similarity between pregnant and non-pregnant women regarding preoperative and postoperative dental pain and catastrophizing and anxiety levels supports the indication of root canal treatment during the gestational period whenever necessary.

Relationship between Periodontal Condition of the Pregnant Woman with Preterm Birth and Low Birth Weight

The aim of this study was to determine the association between the mother’s periodontal condition and perinatal complications, such as preterm birth (PTB) and/or low birth weight (LBW), in a cohort of women in Valencia, Spain. Other related factors, such as tobacco, were also analysed. A prospective cohort study was carried out in a sample of 102 women with a single foetus and ages ranging between 18 and 42 years. Sociodemographic and obstetric variables, caries status, percentage of bleeding, clinical attachment loss (CAL), and probing pocket depth (PPD) data have been collected and analysed. The mean age was 32.4 years, and the BMI was normal. The average weight of new-borns (NB) was 3034 g. A total of 9.8% of the women smoked during their pregnancy. Bleeding percentage was 16.43% (SD 14.81%) and PPDs > 3 mm 8.8 (SD 11.08). The mean of CAL > 0 mm was 1.14 (SD 2.83). The frequency of PTB and LBW was 26%. No statistically significant differences were found between probing depth > 3 mm or CAL > 1 mm, with PTB and/or LBW. Periodontal disease in the mother was not statistically significantly related to either PTB or LBW. Tobacco use during pregnancy showed a statistical significance linked to LBW, but not with PTB.

Evaluation of antimicrobial and cytotoxic effects of Echinacea and Arctium extracts and Zataria essential oil

Dental caries and oral infections have become a widespread issue in the modern world. This study aimed to investigate the antibacterial, antifungal, and cytotoxicity characteristics of the extracts of Echinacea purpura, Arctium lappa, and the essential oil of Zataria multiflora as a potential herbal mouthwash. The essential oil of Z. multiflora leaves and the extracts of E. purpurea and A. lappa roots were prepared. The characterization was carried out by GC-MS and also, total phenol and flavonoid were assed for all three samples. The antimicrobial and anti-biofilm effects were evaluated against Streptococcus mutans, Streptococcus mitis, Streptococcus salivarius, Lactobacillus acidophilus, Escherichia coli, Staphylococcus aureus, and Candida albicans. The cytotoxic effect of the samples was evaluated on HEK 293 and HDFa cells by MTT test. Thymol and carvacrol contents in EO of Z. multiflora were measured at 31% and 42.2%, respectively. A. lappa had the lowest total phenolic and flavonoid value among the samples. On the other hand, the total phenolic content of Z. multiflora and the total flavonoid content of E. purpurea were the highest. The MIC values of Zataria, Arctium, and Echinacea against S. mutans were 0.011% v/v, 187.5 mg/ml, and 93.75 mg/ml, while MBC were 0.011% v/v, 375 mg/ml, and 187.5 mg/ml, respectively. The formulation showed bactericidal activity against S. mutans in the concentration of 5.86 mg/ml for Echinacea and Burdock extracts and 0.08 µl/ml for EO of Zataria. The formulation significantly affected microbial biofilm formation and induced biofilm degradation. The cell viability percentages were higher than 50% during 24 and 48 h. The formulation had a significant antimicrobial effect on cariogenic bacteria and C. albicans, with the lowest cytotoxic effects. Therefore, this formulation can be an appropriate candidate for mouthwash.

Severe Odontogenic Infections during Pregnancy and Related Adverse Outcomes. Case Report and Systematic Literature Review

Odontogenic infections have the potential to develop into deep-space infections and may cause severe diseases with possible life-threatening complications. Dental infections during pregnancy require special attention in terms of possible complications and treatments due to the potential to affect the lives of two individuals. A case of a 36-year-old pregnant patient with a submandibular abscess caused by an odontogenic infection is reported, followed by a comprehensive systematic review of the literature in order to retrieve information regarding severe odontogenic infections and adverse pregnancy outcomes. The review was conducted according to the PRISMA guidelines using PubMed, Scopus, and Google Scholar databases. A total of 69 cases were included in the qualitative analysis. The mean age was 27.72 years. Patients were managed with surgery in combination with antibiotics. Nine infectious-related cesarean sections were detected, and preterm birth was associated in 3 cases, low birth weight in 2 cases, death of the fetus in 9 cases (13%), and maternal death in 4 cases (5.8%). The possible compromise of oral health during pregnancy is well known; however, severe odontogenic infections are rarely considered in the literature, and they may be associated with severe and life-threatening complications for both mother and the fetus.

[Periodontal diseases and complicated pregnancy]

PURPOSE

Based on the datas available in the modern literature, to conduct a study on the effect of dental diseases on the course of pregnancy and outcome; mainly, the impact of periodontal disease on the low birth weight of the newborn and premature birth.

MATERIAL AND METHODS

This article is based on the study of materials from foreign and domestic studies found in the databases Pubmed and Elibrary. Literature data were used for the last 15 years.

RESULTS

The majority of pregnant women who are not receiving due dental examination and suffering with those or other diseases of the oral cavity have an unfavorable outcome of pregnancy, including premature births and low weight of the premature newborn. The role of the chronic effect of oral microorganisms Porphyromonas gingivalis (P. gingivalis) and Fusobacterium nudeatum, as well as local increase in prostaglandin E₂ (PGE₂) and tumor necrosis factor (TNF-α), in the implementation of the inflammatory reaction leading to a decrease in the weight of the fetus by 15-18%.

CONCLUSION

Due to the conducted research it was established that periodontal diseases and other infectious diseases of the oral cavity negatively affect the course of pregnancy and its outcome. The main problems were the lack of women's health education in terms of preparing for pregnancy and sanitation of foci of infection in the oral cavity both before pregnancy and at the time, as well as poor access to the dentist and not receiving proper prevention and, if necessary, treatment of oral diseases.

Protect Tiny Teeth Toolkit: An Oral Health Communications Resource for Providers of Pregnant Women and New Mothers

Oral health is important to general health, yet is often overlooked. During pregnancy, women may be more prone to periodontal (gum) disease and cavities, and research has shown an association between these conditions and adverse pregnancy outcomes. Additionally, a mother's oral health status is a strong predictor of her children's oral health status. Primary care providers often have an opportunity to influence their patients' attitudes and behaviors regarding the importance of oral health during pregnancy. Through a cooperative agreement with the Centers for Disease Control and Prevention, the American Academy of Pediatrics worked to create Protect Tiny Teeth, an oral health communications resource that aims to facilitate conversations between pregnant women and their health care providers, as well as educate women and families about the importance of oral health.

Qualitative assessment of knowledge transfer regarding preterm birth in Malawi following the implementation of targeted health messages over 3 years

Background

In 2012, we performed a needs assessment and gap analysis to qualitatively assess providers’ and patients’ knowledge and perceptions regarding preterm birth (PTB). During the study, we identified knowledge gaps surrounding methods to reduce the risk of occurrence of PTB and management options if preterm labor/birth occur. We targeted health messages toward these gaps. The objective of the present study was to assess the impact of our community health worker-based patient education program 3 years after it was implemented.

Methods

Fifteen focus groups including 70 participants were included in the study. The groups comprised either patients/patient couples or health providers. A minimum of two facilitators led each group using 22 a priori designed and standardized lead-in prompts for participants with four additional prompts for providers only. A single researcher recorded responses, and transcript notes were reviewed by the facilitators and interpreters immediately following each group discussion to ensure accuracy.

Results

The understanding of term vs preterm gestation was generally accurate. Every participant knew of women who had experienced PTB, and the general perception was that two to three women out of every ten had this experience. The majority of respondents thought that women should present to their local health clinic if they experience preterm contractions; few were aware of the use of antenatal steroids for promoting fetal lung maturity, but many acknowledged that the neonate may be able to receive life-sustaining treatment if born at a higher level of care facility. The majority of participants were aware that PTB could recur in subsequent pregnancies. All respondents were able to list ways that women could potentially reduce the risk of PTB.

Conclusion

After employing targeted health messages, the majority of participants expressed improved understanding of the definition of PTB, methods to prevent risk of PTB, and management options for preterm labor or PTB.

Effectiveness of an Oral Health Education Program for Obstetrician/Gynecologist Residents at Tufts Medical Center

Aim and Objectives:

To assess Tufts Medical Center obstetrician/gynecologist (OB/GYN) residents' knowledge, beliefs, and previous training in oral health and to assess the effect of an oral health educational seminar on their knowledge and beliefs.

Materials and Methods:

A preseminar questionnaire was distributed to the residents. The same questionnaire was distributed immediately after the seminar and 3 months later. SPSS Version 21 was used for the data analysis.

Results:

Convenience sample of 25 residents were included in the study. The mean (standard deviation) age of participants was 29.08 (2.47) years. Only 1 (4%) participant reported receiving >8 h previous training in oral health and 7 (28%) reported receiving <1 h of training. The nonparametric Friedman test showed a statistically significant difference between administrations in terms of total score on knowledge-based questions (P < 0.001) and some of the belief-based questions. The post hoc Wilcoxon signed-rank test with Bonferroni correction showed statistically significant improvement in the knowledge-based questions between pre- and post-seminar questionnaire (P = 0.002) and between preseminar and 3-month follow-up (P = 0.003).

Conclusions:

OB/GYN residents at Tufts Medical Center received limited training in oral health. Their knowledge improved significantly following the oral health educational seminar. Similar training modules can be brought to other OB/GYN residencies and OB/GYNs in an effort to enhance the symbiotic relationship between medical and dental professionals.

Further evidence for periodontal disease as a risk indicator for adverse pregnancy outcomes

BACKGROUND

Although there is increasing evidence to suggest an association between periodontal disease and adverse pregnancy outcomes, the issue remains controversial.

STUDY OBJECTIVE

This study tested the hypothesis that periodontal disease is a risk indicator for preterm delivery of low-birthweight infants.

MATERIALS AND METHODS

The study sample comprised 443 pregnant women with a mean (± standard deviation) age of 24.13 (±5.30) years. At first visit, maternal oral health status was assessed by the measurement of probing pocket depth and clinical attachment loss, and periodontal status was graded as absent, mild, moderate or severe. An association was sought between pregnancy outcomes and maternal periodontal status.

RESULTS

While controlling for other factors, significant associations were found between pregnancy outcomes and maternal periodontal index scores.

CONCLUSION

This study provides further evidence that periodontal disease is a risk indicator for adverse pregnancy outcomes.

A Prospective Cohort Study to Assess and Correlate the Maternal Periodontal Status with Their Pregnancy Outcome

BACKGROUND

There is an overwhelming body of evidence strongly suggesting that periodontal infection may have a significant negative impact on pregnancy outcome in some women. The aim of this study was to determine the association between periodontal disease and preterm low birth weight of babies.

MATERIALS AND METHODS

A total of 300 pregnant women, between 20 and 24 weeks of gestation i.e., second trimester, were considered for the study. The periodontal status was recorded using the following parameters: probing pocket depth, clinical attachment level, oral hygiene index and plaque index. After initial examination in the second trimester, the pregnant women were followed till delivery of the baby. Postpartum data i.e., weight of baby, gestational age of pregnancy and type of delivery, were recorded.

RESULTS

Out of 300 pregnant women, 248 women had full-term delivery (12 low birth weight and 236 normal birth weight) while 52 had preterm delivery (6 normal birth weight and 46 low birth weight). There was significant association between body mass index and level of periodontal disease severity of pregnant women with birth weight of babies, gestational age of pregnant women and mode of delivery, respectively. As the level of periodontal disease severity increased, the proportion of delivering preterm and low birth weight babies also increased.

CONCLUSION

The conclusions obtained revealed that Periodontal disease is a potential risk factor for preterm low birth weight babies of pregnant women.

Dental pain and associated factors among pregnant women: an observational study

The present study aimed to determine the prevalence of dental pain during pregnancy and its association with sociodemographic factors and oral health conditions among 315 pregnant women in South Brazil. Participants were interviewed to obtain sociodemographic data, such as age, educational level, employment status, family income, and marital and parity status. Medical and dental histories were also collected, including the occurrence of dental pain and the use of dental services during pregnancy. Clinical examinations were performed to assess the presence of visible plaque and gingival bleeding and to calculate the decayed, missing, and filled teeth index. Means and standard deviations of continuous variables and frequencies and percentages of categorical variables were calculated. Independent variables were included in a multivariate logistic regression analysis. A total of 173 (54.9 %) pregnant women reported dental pain during pregnancy. After adjustment of the analysis, caries activity remained the main determinant of dental pain (odds ratio 3.33, 95 % CI 1.67-6.65). The prevalence of dental pain during pregnancy was high and the presence of caries activity was a determinant of dental pain. Moreover, access to oral health care was low, despite pregnant women's increased need for dental assistance.

Bi-directional relationship between pregnancy and periodontal disease

During pregnancy profound perturbations in innate and adaptive immunity impact the clinical course of a number of infectious diseases, including those affecting periodontal tissues. Conversely, it has been suggested that periodontal infections may increase the risk of adverse pregnancy outcomes. In this review, a summary of the literature associated with the bidirectional relationship between pregnancy and periodontal disease as well as the possible mechanisms behind this interaction were examined.

Antimicrobial activity and mechanism of action of a novel cationic α-helical dodecapeptide, a partial sequence of cyanate lyase from rice

CL(14-25), a dodecapeptide, that is a partial region near N-terminus of cyanate lyase (CL, EC 4.3.99.1) from rice (Oryza sativa L. japonica), contains three arginine and two lysine residues. It was a novel cationic α-helical antimicrobial peptide. The antimicrobial activity of CL(14-25) against Porphyromonas gingivalis, a periodontal pathogen, was quantitatively evaluated by a chemiluminescence method that measures ATP derived from viable cells. The 50% growth-inhibitory concentration of CL(14-25) against P. gingivalis cells was 145 μM. CL(14-25), even at a concentration of 800 μM, had no hemolytic activity. When giant unilamellar vesicles (GUVs) that mimic the membrane composition of Gram-negative bacteria were used, microscopy image analysis suggested that CL(14-25) disrupted GUVs in a detergent-like manner. Therefore, CL(14-25) appears to exhibit antimicrobial activity through membrane disruption. To investigate the contribution of cationic amino acid residues in CL(14-25) to its antimicrobial activity, we synthesized four truncated CL analogs, in which one or two cationic amino acid residues were deleted from the N- and C- termini of CL(14-25). The degrees of calcein leakage from large unilamellar vesicles (LUVs) and 3,3'-dipropylthiadicarbocyanine iodide (diSC3-5) release from P. gingivalis cells induced by truncated CL analogs were closely related to their antimicrobial activities. CL analogs, which were truncated by removing an arginine residue from the N-terminus and a lysine residue from the C-terminus maintained their antimicrobial activity. However, CL analogs, which were further truncated by removing two arginine residues from the N-terminus, and an arginine and a lysine residue from the C-terminus, rarely exhibited antimicrobial activity.

Very low and low birth weight associated with maternal periodontitis

AIM

The aim of this study was to evaluate the association of very low and low birth weight (VLBW and LBW) with maternal periodontitis.

MATERIAL AND METHODS

Overall, 1206 women were examined at post-partum and two alternative criteria for periodontitis definition were used: (1) four or more teeth with at least one site with probing depth (PD) ≥ 4 mm and clinical attachment loss (CAL) ≥ 3 mm; and (2) at least one site with PD and CAL ≥ 4 mm. For each definition, two multivariate analyses were performed: (1) linear regression for birth weight; (2) ordinal logistic regression for birth weight, categorized as adequate (n = 1046), LBW (n = 145) and VLBW (n = 15).

RESULTS

Linear regression showed that maternal periodontitis was associated with a decrease in mean birth weight (periodontitis definition 1: p = 0.027; periodontitis definition 2: p = 0.003). Ordinal logistic regression showed that maternal periodontitis was associated with LBW and VLBW [odds ratio (OR) = 2.0; 95% confidence interval (CI) 1.39-2.90, when considering periodontitis definition 2]; and with LBW (OR = 1.65; 95% CI 1.15-2.36, when considering periodontitis definition 1).

CONCLUSION

Maternal periodontitis was associated with a decrease in mean birth weight, as well as with LBW and VLBW.

Causes of adverse pregnancy outcomes and the role of maternal periodontal status - a review of the literature

Preterm (PT) and Low birth weight (LBW) are considered to be the most relevant biological determinants of newborn infants survival, both in developed and in developing countries. Numerous risk factors for PT and LBW have been defined in the literature. Infections of the genitourinary tract infections along with various biological and genetic factors are considered to be the most common etiological factors for PT/LBW deliveries. However, evidence suggests that sub-clinical infection sites that are also distant from the genitor-urinary tract may be an important cause for PT/LBW deliveries. Maternal periodontal status has also been reported by many authors as a possible risk factor for PT and LBW, though not all of the actual data support such hypothesis. The aim of this paper is to review the evidence from various published literature on the association between the maternal periodontal status and adverse pregnancy outcomes. Although this review found a consistent association between periodontitis and PT/LBW, this finding should be treated with great caution until the sources of heterogeneity can be explained.

Pathogenic mechanisms linking periodontal diseases with adverse pregnancy outcomes

In the last 2 decades, a large proportion of studies have focused on the relationship between maternal periodontal disease and poor obstetric outcomes. The aim of the present review is to summarize the current knowledge about human studies on the pathogenetic mechanisms linking periodontal diseases with adverse pregnancy outcomes. A search of the medical literature was conducted using NIH (National Institute of Health) Pubmed through April 2011. Articles were identified with the Medical Subject Heading (MeSH) and free text terms "small for gestational age (SGA)," "preeclampsia," "preterm labor," and "periodontal disease." Experimental human studies have shown that periodontal pathogens may disseminate toward placental and fetal tissues accompanied by an increase in inflammatory mediators in the placenta. As such, new inflammatory reactions within the placental tissues of the pregnant woman may occur, the physiological levels of prostaglandin E(2) (PGE(2)) and tumor necrosis factor-α (TNF-α) in the amniotic fluid may increase and eventually lead to premature delivery. Although many data from clinical trials suggest that periodontal disease may increase the adverse pregnancy outcome, the exact pathogenetic mechanism involved remains controversial. The findings explain the potential link between periodontal infections and adverse pregnancy outcomes. First, periodontal bacteria can directly cause infections both of the uteroplacenta and the fetus; second, systemic inflammatory changes induced by periodontal diseases can activate responses at the maternal-fetal interface. Of note, associative studies have produced different results in different population groups and no conclusive evidence has still been produced for the potential role of preventive periodontal care to reduce the risk factors of preterm birth.

Periodontal treatment during pregnancy decreases the rate of adverse pregnancy outcome: a controlled clinical trial

Objectives

The aim of this study was to evaluate the effects of non-surgical treatment of periodontal disease during the second trimester of gestation on adverse pregnancy outcomes.

Material and Methods

Pregnant patients during the 1^st and 2^nd trimesters at antenatal care in a Public Health Center were divided into 2 groups: NIG – "no intervention" (n=17) or IG- "intervention" (n=16). IG patients were submitted to a non-surgical periodontal treatment performed by a single periodontist consisting of scaling and root planning (SRP), professional prophylaxis (PROPH) and oral hygiene instruction (OHI). NIG received PROPH and OHI during pregnancy and were referred for treatment after delivery. Periodontal evaluation was performed by a single trained examiner, blinded to periodontal treatment, according to probing depth (PD), clinical attachment level (CAL), plaque index (PI) and sulcular bleeding index (SBI) at baseline and 35 gestational weeks-28 days post-partum. Primary adverse pregnancy outcomes were preterm birth (<37 weeks), low birth weight (<2.5 kg), late abortion (14-24 weeks) or abortion (<14 weeks). The results obtained were statistically evaluated according to OR, unpaired t test and paired t test at 5% significance level.

Results

No significant differences were observed between groups at baseline examination. Periodontal treatment resulted in stabilization of CAL and PI (p>0.05) at IG and worsening of all periodontal parameters at NIG (p<0.0001), except for PI. Significant differences in periodontal conditions of IG and NIG were observed at 2nd examination (p<0.001). The rate of adverse pregnancy outcomes was 47.05% in NIG and 6.25% in IG. Periodontal treatment during pregnancy was associated to a decreased risk of developing adverse pregnancy outcomes [OR=13.50; CI: 1.47-123.45; p=0.02].

Conclusions

Periodontal treatment during the second trimester of gestation contributes to decrease adverse pregnancy outcomes.

Periodontal disease and adverse pregnancy outcomes

Periodontal disease is a common infectious disease in women of reproductive age. The disease is often not diagnosed and in studies of over 10 000 women has been associated with preterm birth, small for gestational age newborns, and preeclampsia. It has been shown in a smaller number of women that treatment of periodontal disease may reduce the rate of preterm birth. The pregnancy complications of periodontal disease may be due to lipopolysaccharide from the periodontal pockets inciting prostaglandin pathways controlling parturition. Three large randomized controlled trials of treatment of periodontal disease are underway and may provide confirmation of the importance of periodontal disease in causing complications of pregnancy.

Is maternal periodontal disease a risk factor for preterm delivery?

Several studies have suggested an association between maternal periodontal disease and preterm delivery, but this has not been a consistent finding. In 2006-2007, the authors examined the relation between maternal periodontal disease and preterm delivery among 467 pregnant Thai women who delivered a preterm singleton infant (<37 weeks' gestation) and 467 controls who delivered a singleton infant at term (> or =37 weeks' gestation). Periodontal examinations were performed within 48 hours after delivery. Participants' periodontal health status was classified into 4 categories according to the extent and severity of periodontal disease. Logistic regression was used to estimate odds ratios and 95% confidence intervals. Preterm delivery cases and controls were similar with regard to mean probing depth, mean clinical attachment loss, and mean percentage of sites exhibiting bleeding on probing. After controlling for known confounders, the authors found that severe clinical periodontal disease was not associated with an increased risk of preterm delivery (odds ratio = 1.20, 95% confidence interval: 0.67, 2.16). In addition, there was no evidence of a linear increase in risk of preterm delivery or its subtypes associated with increasing severity of periodontal disease (P(trend) > 0.05). The results of this case-control study do not provide convincing evidence that periodontal disease is associated with preterm delivery or its subtypes among Thai women.

A critical assessment of adverse pregnancy outcome and periodontal disease

BACKGROUND

Pre-term birth is a major cause of infant mortality and morbidity that has considerable societal, medical, and economic costs. The rate of pre-term birth appears to be increasing world-wide and efforts to prevent or reduce its prevalence have been largely unsuccessful.

AIM

To review the literature for studies investigating periodontal disease as a possible risk factor for pre-term birth and adverse pregnancy outcomes.

MAIN FINDINGS AND CONCLUSION

Variability among studies in definitions of periodontal disease and adverse pregnancy outcomes as well as widespread inadequate control for confounding factors and possible effect modification make it difficult to base meaningful conclusions on published data. However, while there are indications of an association between periodontal disease and increased risk of adverse pregnancy outcome in some populations, there is no conclusive evidence that treating periodontal disease improves birth outcome. Based on a critical qualitative review, available evidence from clinical trials indicates that, although non-surgical mechanical periodontal treatment in the second trimester of pregnancy is safe and effective in reducing signs of maternal periodontal disease, it does not reduce the rate of pre-term birth. Clinical trials currently underway will further clarify the potential role of periodontal therapy in preventing adverse birth outcomes. Regardless of the outcomes of these trials, it is recommended that large, prospective cohort studies be conducted to assess risk for adverse pregnancy outcome in populations with periodontal disease. It is critical that periodontal exposure and adverse birth outcomes be clearly defined and the many potential confounding factors and possible effect modifiers for adverse pregnancy outcome be controlled in these studies. If periodontal disease is associated with higher risk of adverse pregnancy outcome in these specific populations, large multicenter randomized-controlled trials will be needed to determine if prevention or treatment of periodontal disease, perhaps combined with other interventions, has an effect on adverse pregnancy outcome in these women.

Periodontal disease and pregnancy outcomes: state-of-the-science

To examine the existing evidence on the relationship between periodontal disease and adverse pregnancy outcomes, we conducted a systematic review of studies published up to December 2006. Studies published in full text were identified by searching computerized databases (e.g., MEDLINE, EMBASE). A meta-analysis was performed to pool the effect size of the clinical trials. Forty-four studies were identified (26 case-control studies, 13 cohort studies, and 5 controlled trials). The studies focused on preterm low birth weight, low birth weight, preterm birth, birth weight by gestational age, miscarriage or pregnancy loss, preeclampsia, and gestational diabetes mellitus. Of the chosen studies, 29 suggested an association between periodontal disease and increased risk of adverse pregnancy outcome (odds ratios [ORs] ranging from 1.10 to 20.0) and 15 found no evidence of an association (ORs ranging from 0.78 to 2.54). A meta-analysis of the clinical trials suggested that oral prophylaxis and periodontal treatment may reduce the rate of preterm low birth weight (pooled risk ratio (RR): 0.53, 95% confidence interval [CI]: 0.30-0.95, P < 0.05), but did not significantly reduce the rates of preterm birth (pooled RR: 0.79, 95% CI: 0.55-1.11, P > 0.05) or low birth weight (pooled RR: 0.86, 95% CI: 0.58%1.29, P > 0.05). The authors conclude that periodontal disease may be associated with increased risk of adverse pregnancy outcomes. More methodologically rigorous studies are needed in this field. Currently, there is insufficient evidence to support the provision of periodontal treatment during pregnancy for the purpose of reducing adverse pregnancy outcomes.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader should be able to state that the published literature is not vigorous to clinically link periodontal disease and/or its treatment to specific adverse pregnancy outcomes, and explain that more rigorous studies with world-wide agreed-upon definitions are particularly needed before periodontal disease treatment can be recommended.

Periodontal disease as a risk factor for adverse pregnancy outcomes: a prospective cohort study

AIM

The aim of this study was to determine the association between periodontitis and the incidence of preterm birth (PB), low birth weight (LBW) and preterm low birth weight (PLBW) MATERIAL AND METHODS: One thousand and ninety-six women were enrolled. Periodontal data, pregnancy outcome variables and information on other factors that may influence adverse pregnancy outcomes were collected. Data were analysed using a logistic regression model.

RESULTS

The incidence of PB and LBW was 6.6% and 6.0%, respectively. The incidence of PLBW was 3.3%. PB was related to mother's age, systemic diseases, onset of prenatal care, previous PBs, complications of pregnancy, type of delivery, the presence of untreated caries and the presence of periodontitis (odds ratio 1.77, 95% confidence interval: 1.08-2.88). LBW was related to mother's smoking habits, ethnicity, systemic diseases, previous LBW babies, complications of pregnancy and type of delivery. PLBW was related to mother's age, onset of prenatal care, systemic diseases, previous LBW babies, complications of pregnancy and type of delivery.

CONCLUSIONS

The factors involved in many cases of adverse pregnancy outcomes have still not being identified, although systemic infections may play a role. This study found a modest association between periodontitis and PB. Further research is required to establish whether periodontitis is a risk factor for PB and/or LBW.

Evaluation of the incidence of preterm low birth weight in patients undergoing periodontal therapy

BACKGROUND

Preterm low birth weight was reported to be related to periodontal infections that might influence the fetus-placenta complex. The aim of this study was to provide periodontal treatment for pregnant women and to evaluate if this treatment can interfere with pregnancy duration and weight of the newborn.

METHODS

The sample consisted of 450 pregnant women who were under prenatal care at a polyclinic in Três Corações, Brazil. Women with risk factors, such as systemic alterations (ischemic cardiopathy, hypertension, tuberculosis, diabetes, cancer, anemia, seizure, psychopathology, urinary tract infection, sexually transmitted diseases, asthma, and human immunodeficiency virus), and/or users of alcohol, tobacco, and drugs were excluded from the study. Data related to age, socioeconomic level, race, marital status, number of previous pregnancies, and previous preterm delivery also were evaluated. Initially, the sample was divided into two groups: 122 healthy patients (group 1) and 328 patients with periodontal disease (group 2). In group 2, 266 patients underwent treatment and 62 patients dropped out. After mothers gave birth, pregnancy duration and the weight of all infants were analyzed and recorded.

RESULTS

There was no statistical difference between the healthy and treated groups. However, there was a difference in the non-treated group, with a 79% incidence of preterm low birth weight. Educational level, previous preterm birth, and periodontal disease were related significantly to preterm delivery (P <0.001).

CONCLUSION

Periodontal disease was related significantly to preterm low birth weight.

Periodontal disease and pregnancy outcomes: exposure, risk and intervention

Despite the many advances in medicine, the rate of preterm birth has not significantly decreased in the United States over the past several decades. In fact, the rate rose in 2003 to more than 12% of all births in the United States. This equates to over half a million premature births in the United States alone. Consequently, the identification of risk factors for preterm birth which are amenable to intervention would have far-reaching and long-lasting effects. There is emerging evidence of a relationship between periodontal health and adverse pregnancy outcomes, particularly preterm birth/preterm low-birth-weight infants. Therefore this chapter explores the putative association between periodontal disease and infant prematurity, as well as the results of intervention studies which treated periodontal disease in order to reduce the incidence of prematurity. Of 31 published studies, 22 show a positive association between premature birth and periodontal disease. Ongoing studies are addressing the efficacy of periodontal treatment for decreasing the incidence of infant prematurity.

Exploring the relationship between periodontal disease and pregnancy complications

BACKGROUND

Increasing evidence suggests that maternal gingivitis and periodontitis may be a risk factor for preterm birth and other adverse pregnancy outcomes.

TYPES OF STUDIES REVIEWED

To clarify the possible mechanisms behind the association between periodontal disease and preterm delivery, the authors reviewed studies of the effect of infection with periodontal pathogens in animal models on pregnancy outcomes including fetal growth, placental structural abnormalities and neonatal health. After the first report, in 1996, of a potential association between maternal periodontal disease and delivery of a preterm/low-birth-weight infant in humans, many case control and prospective studies were published. This review summarizes these, as well as early studies involving periodontal intervention to reduce risk.

RESULTS

Although there are some conflicting findings and potential problems regarding uncontrolled underlying risk factors, most of the clinical studies indicate a positive correlation between periodontal disease and preterm birth. Recent studies also have shown that there are microbiologic and immunological findings that strongly support the association. The studies indicate that periodontal infection can lead to placental-fetal exposure and, when coupled with a fetal inflammatory response, can lead to preterm delivery. Data from animal studies raise the possibility that maternal periodontal infections also may have adverse long-term effects on the infant's development.

CLINICAL IMPLICATIONS

Education for patients and health care providers regarding the biological plausibility of the association and the potential risks is indicated, but there is insufficient evidence at this time for health care policy recommendations to provide maternal periodontal treatments for the purpose of reducing the risk of adverse pregnancy outcomes.

Exploring the Sn binding pockets in gingipains by newly developed inhibitors: structure-based design, chemistry, and activity

Arg-gingipains (Rgps) and Lys-gingipain (Kgp) are cysteine proteinases secreted by Porphyromonas gingivalis, the major pathogen implicated in periodontal disease. Gingipains are essential to the bacterium for its virulence and survival, and development of inhibitors targeting these proteins provides an approach to treat periodontal diseases. Here, we present the first example of structure-based design of gingipains inhibitors, with the use of the crystal structure of RgpB and the homology model of Kgp. Chloromethyl ketones were selected as suitable compounds to explore the specificity of the Sn binding region of both enzymes. Three series of inhibitors bearing Arg or Lys at P1 and different substituents at P2 and P3 were designed, synthesized, and tested. High potency (k(obs)/[I] approximately 10(7) M(-1) s(-1)) was achieved for small ligands, such as the dipeptide analogues. The detailed analysis of Sn binding pockets revealed the molecular basis of inhibitory affinity and provided insight into the structure-activity relationship.

Periodontal disease and adverse pregnancy outcomes: a systematic review

BACKGROUND

Recent studies suggest that periodontal disease, as a source of subclinical and persistent infection, may induce systemic inflammatory responses that increase the risk of adverse pregnancy outcomes.

OBJECTIVES

To examine the existing evidence on the relationship between periodontal disease and adverse pregnancy outcomes.

SEARCH STRATEGY

Published studies identified via searches of the MEDLINE, EMBASE, CINAHL, and Current Contents full-text databases.

SELECTION CRITERIA

We identified and selected observational studies (i.e. case-control, cross-sectional, and cohort) and nonrandomised controlled studies or randomised controlled trials that examined periodontal disease as a risk factor for adverse pregnancy outcomes.

DATA COLLECTION AND ANALYSIS

Odds ratios (OR) or risk ratios (RR) were extracted or calculated from the studies' data. We calculated pooled effect size for two clinical controlled trials but not for the observational studies due to the heterogeneity in definitions for periodontal disease and adverse pregnancy outcomes across studies.

MAIN RESULTS

Twenty-five studies (13 case-control, 9 cohort, and 3 controlled trials) were identified. The studies focused on preterm low birthweight, low birthweight, preterm birth, birthweight by gestational age, miscarriage or pregnancy loss, and pre-eclampsia. Of the chosen studies, 18 suggested an association between periodontal disease and increased risk of adverse pregnancy outcome (ORs ranging from 1.10 to 20.0) and 7 found no evidence of an association (ORs ranging from 0.78 to 2.54). Three clinical trial studies suggest that oral prophylaxis and periodontal treatment can lead to a 57% reduction in preterm low birthweight (pooled RR 0.43; 95% CI 0.24-0.78) and a 50% reduction in preterm births (RR 0.5; 95% CI 0.20-1.30).

AUTHOR'S CONCLUSIONS

Periodontal disease may be associated with an increased risk of adverse pregnancy outcome. However, more methodologically rigorous studies are needed for confirmation.

Progressive periodontal disease and risk of very preterm delivery

OBJECTIVE

The goal was to estimate whether maternal periodontal disease was predictive of preterm (less than 37 weeks) or very preterm (less than 32 weeks) births.

METHODS

A prospective study of obstetric outcomes, entitled Oral Conditions and Pregnancy (OCAP), was conducted with 1,020 pregnant women who received both an antepartum and postpartum periodontal examination. Predictive models were developed to estimate whether maternal exposure to either periodontal disease at enrollment (less than 26 weeks) and/or periodontal disease progression during pregnancy, as determined by comparing postpartum with antepartum status, were predictive of preterm or very preterm births, adjusting for risk factors including previous preterm delivery, race, smoking, social domain variables, and other infections.

RESULTS

Incidence of preterm birth was 11.2% among periodontally healthy women, compared with 28.6% in women with moderate-severe periodontal disease (adjusted risk ratio [RR] 1.6, 95% confidence interval [CI] 1.1-2.3). Antepartum moderate-severe periodontal disease was associated with an increased incidence of spontaneous preterm births (15.2% versus 24.9%, adjusted RR 2.0, 95% CI 1.2-3.2). Similarly, the unadjusted rate of very preterm delivery was 6.4% among women with periodontal disease progression, significantly higher than the 1.8% rate among women without disease progression (adjusted RR 2.4, 95% CI 1.1-5.2).

CONCLUSION

The OCAP study demonstrates that maternal periodontal disease increases relative risk for preterm or spontaneous preterm births. Furthermore, periodontal disease progression during pregnancy was a predictor of the more severe adverse pregnancy outcome of very preterm birth, independently of traditional obstetric, periodontal, and social domain risk factors.

LEVEL OF EVIDENCE

II-2.

Is pre-term labour associated with periodontitis in a Danish maternity ward?

OBJECTIVES

To reveal differences in periodontal status and presence of subgingival bacteria in a Scandinavian population of women with pre-term birth compared with women who delivered at term.

MATERIALS AND METHODS

Twenty-one women with pre-term labour (before week 35) and 33 women with term labour (between weeks 38 and 41) were included in this case-control study. Periodontal measurements included plaque index (PlI), probing pocket depth (PPD) and bleeding on probing (BOP). Inter-proximal distances from the cemento-enamel junction (CEJ) to the marginal bone crest (MBC) were measured on bitewing radiographs. In 31 patients (16 cases and 15 controls) the subgingival plaque was analysed using "checkerboard" DNA-DNA hybridization.

RESULTS

Differences between the two examined groups were found related to "Twin births" (p=0.0064) and "Smokers" (p=0.03). None of the periodontal measurements showed any association. Significant differences were found concerning presence of Tannerella forsythensis, Treponema denticola, Peptostreptococcus micros, Streptococcus intermedius, Streptococcus oralis, Streptococcus sanguis and Capnocytophaga ochracea but when defining sites with >10(5) bacteria as heavily colonized, no statistical difference was found between the two groups.

CONCLUSION

A relation between pre-term birth and periodontitis was not revealed in the present study.

Oral health in women with pregnancy and delivery complications

Oral health was retrospectively studied in 207 women (mean age 30 years) in the Helsinki Womens' Hospital with the hypothesis that women with pregnancy complications and/or delivery complications would present poorer dental status than women without complications. Computerized dental records of the City of Helsinki Health Department were used with decayed, missing, filled index (DMF) and community periodontal index (CPI) scoring systems and a summary dental health index (DHI) was constructed for statistics. In 72%, the delivery was uncomplicated, while 18% had Caesarean section. Of the women, 8% had gestational diabetes, 7.1% had gestational hypertension, and 1.8% had preeclampsia. Fifteen (6.6%) preterm babies were born; eight (3.5%) babies weighed <2.500 g, seven (3.2%) received a 1-min Apgar point <7 indicating less than satisfactory state of the newborn. DMF was 12.9+/-6.6 in women without complications compared to 15.3+/-6.7 in women with complications (n.s.). CPI values did not differ between the groups. The mean DHI values were 2.07 in women with normal pregnancy complications and no delivery complications, 2.23 in those with pregnancy complications, and 2.13 in those with delivery complications, respectively. In logistic regression analysis, no oral health parameters associated with any complications. Thus, this study failed to show an association between poor dental health and pregnancy or delivery complications.

Distribution of anaerobic bacteria among pregnant periodontitis patients who experience preterm delivery

The preterm delivery of low-birth-weight (PLBW) infants remains a significant public health issue and a leading cause of neonatal death and of long-term neurodevelopmental disturbances and health problems. Epidemiological and immunological studies have suggested that periodontal disease may be an independent risk factor for PLBW. The incidence of periodontal disease during pregnancy has been found to be associated with a significantly lower birth weight for gestational age after adjustment for race, parity and baby gender. The present case-control study, carried out to examine the distribution of anaerobes in pregnant women with periodontitis who experienced preterm delivery, provides microbial evidence that maternal periodontal disease and the presence of key pathogens are significant contributors to the obstetric risk of preterm delivery.

Correlation between infant birth weight and mother's periodontal status

OBJECTIVES

Recent studies have suggested that periodontal disease is a risk factor for low birth weight (LBW) with other multiple factors. A cross-sectional study was undertaken to help further evaluate the proposed association between periodontal disease and infant birth weight.

MATERIAL AND METHODS

Caucasian pregnant women (n=152), aged 14-39 years, were enrolled while receiving prenatal care. Dental plaque, probing depth, bleeding on probing and clinical attachment level were recorded and three groups were made: healthy group (HG) (n=38), gingivitis group (GG) (n=71) and periodontitis group (PG) (n=43). At delivery, birth weight was recorded.

RESULTS

Infant mean weight at delivery was 3293.9+/-508.1 g. The total incidence of preterm birth and LBW infants was 5.3% and 4.6%, respectively. The incidence of LBW infants was 3.5% in term gestations and 25% in preterm gestations. Mothers height correlated with infant birth weight (p=0.03). Significant difference in birth weight existed between mothers with <1.55 m (3229.23+/-462.57) and those with > or =1.65 m (3475.55+/-505.07). In the group of women >25 years old infant mean weight in HG was 3588.33+/-531.83, being lower in GG (3466.75+/-334.45) and even lower (3092.60+/-592.94) in PG (p=0.0198). Bleeding on probing was significantly greater in women with <2500 g infants (40.2+/-21.8%) compared with 2500-3499 g (18.6+/-15.1%) and > or =3500 g (17.1+/-16.1%) (p=0.009).

CONCLUSIONS

Periodontal disease in normal Caucasian pregnant women, older than 25 years, is statistically associated with a reduction in the infant birth weight. These data provide new evidence on the relationship between periodontal disease and birth weight.

Periodontal infections and pre-term low birth weight: a case-control study

OBJECTIVE

Pre-term delivery of low-birth-weight infants [pre-term low birth weight (PLBW)] remains a significant public health issue and a major cause of neonatal death and long-term health problems. There is a growing consensus that infections remote from fetal-placental unit may influence PLBW infants. Recent studies have suggested that maternal periodontal disease may be an independent risk factor for PLBW. The purpose of the present study was to evaluate the possible link between periodontal infections and PLBW by means of clinical and microbiological data in post-partum women with low socioeconomic level.

METHODS

Clinical periodontal recordings comprising dental plaque, bleeding on probing, probing pocket depth and gingival recession were performed (six sites/tooth) in a total number of 181 women (53 cases and 128 controls) within 3 days post-partum. Subgingival plaque samples from mesio-or disto-buccal aspect of randomly selected one first molar and one incisor tooth have been obtained by paperpoints and were analysed by checkerboard DNA-DNA hybridization with respect to 12 bacterial species. In all analyses, the individual subject was the computational unit. Thus, mean values for all clinical parameters were calculated and bacterial scores from each individual sample were averaged. Statistical methods included Student's t-test, Fisher's exact test/chi(2) test, and multiple logistic regression analysis.

RESULTS

The cases have gained significantly less weight during the pregnancy than did the controls (p<0.05). There were no statistically significant differences between the cases and controls with regard to the dental and periodontal parameters and the values of clinical periodontal recordings were found to be very similar (p>0.05). Mean and median scores (bacterial loads) of Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens, Actinobacillus actinomycetemcomitans, and Streptococcus intermedius in the subgingival plaque sampling sites were significantly higher in the controls than in the cases (p<0.05). The occurrence rates of P. intermedia, Fusobacterium nucleatum, Peptostreptococcus micros, Campylobacter rectus, Eikenella corrodens, Selenomonas noxia and S. intermedius were higher in the cases compared with the controls, but the differences were not statistically significant (p>0.05). According to the model created by the multiple logistic regression analysis, P. micros and C. rectus were found to significantly increase the risk of PLBW (p<0.01 and p<0.05 respectively), while P. nigrescens and A. actinomycetemcomitans decreased this risk (p<0.01).

CONCLUSION

The present findings indicated that when subgingival bacteria were evaluated together, P. micros and C. rectus may have a role in increasing the risk for PLBW, although no single bacteria exhibited any relation with the risk of PLBW. Further studies are required to better clarify the possible relationship between periodontal diseases and PLBW.

Suppression of pathogenicity of Porphyromonas gingivalis by newly developed gingipain inhibitors

Arg-gingipain (Rgp) and Lys-gingipain (Kgp) are cysteine proteinases produced by Porphyromonas gingivalis, a major etiological bacterium of periodontal diseases. Here we show a series of small peptide analogs able to inhibit either Rgp or Kgp, which are synthesized on the basis of the cleavage site specificity of human salivary histatins by each enzyme. Among this series of compounds, carbobenzoxy-Lys-Arg-CO-Lys-N-(CH2)2 (KYT-1) and carbobenzoxy-Glu(NHN(CH3)Ph)-Lys-CO-NHCH2Ph (KYT-36) were found to be the most potent inhibitors of Rgp and Kgp, respectively, with Ki values of 10(-11) to 10(-10) M order. Both inhibitors exhibited slight or no inhibition on mammalian proteinases such as trypsin and cathepsins B, L, and H. All of the virulence induced by the culture supernatant of P. gingivalis tested, including the degradation of various host proteins such as human type I collagen, immunoglobulins, fibronectin, and fibrinogen, disruption of the bactericidal activity of polymorphonuclear leukocytes, and enhancement of the vascular permeability, were strongly inhibited by a combined action of both inhibitors. The functions essential for the bacterium to grow and survive in the periodontal pocket, such as coaggregation and acquisition of amino acids, were also strongly inhibited by the combined action of both inhibitors. The disruption of the adhesion and viability of human fibroblasts and hemagglutination by the organism were strongly suppressed by a single use of KYT-1. These results thus indicate that the newly developed KYT-1 and KYT-36 both should provide a broader application in studies of this important class of enzymes and facilitate the development of new approaches to periodontal diseases.

A possible association between preterm birth and early periodontitis. Pilot study

According to many studies, generalised periodontitis can be a risk factor for preterm birth (PB). A case-control study was carried out to examine if early localised periodontitis could be a risk factor for adverse pregnancy outcome.

MATERIAL AND METHODS

Postpartum women without any systemic disease were included into the study. Similar numbers of patients belonged to the case (41) and to the control (44) groups. A PB case was defined if a patient had a threatening premature labour during pregnancy, preterm premature rupture of membranes, or spontaneous preterm labour, and/or the weight of the newborn was < or = 2499 g. Control women had delivery after the 37th gestational week and the newborn's weight was > or = 2500 g. Known risk factors like smoking, alcohol, drug consumption, socio-economic status and the periodontal status were recorded.

RESULTS

A significant association was found between PB and early localised periodontitis of the patient with the following criterion having bleeding at > or = 50% of the examined sites (6 at each tooth) and having at least at one site > or = 4 mm probing depth (p = 0.001). The odds ratio was 5.46 at the 95% confidence interval. The average weight of the newborns in the periodontitis group was less than in the control group, the difference is significant (p = 0.047).

CONCLUSION

The results indicate that early localised periodontitis of the patient during pregnancy can be regarded as an important risk factor for PB.