The use of different measurements and definitions of periodontal disease in the study of the association between periodontal disease and risk of myocardial infarction

BACKGROUND: The role of periodontal disease as an independent risk factor for cardiovascular disease (CVD) has been under debate because of the inconsistency of findings across studies. One of the major issues is the method used to assess or define periodontal disease. The present study assesses if the observed association between periodontal disease and incident myocardial infarction (MI) depends on the measurements and/or criteria used to define periodontal disease. METHODS: A population-based case-control study to evaluate the association between PD and risk of MI was conducted between 1997 and 2001 in Western New York with 537 cases and 800 controls, aged 35 to 69 years. Cases were survivors of incident MI from local hospitals in Erie and Niagara counties. Controls were randomly selected from residents of the same counties. Periodontal disease was assessed using interproximal clinical attachment loss (CAL), probing depth (PD), alveolar crest height (ACH), and number of missing teeth. From these measurements, four different case definitions of periodontal disease were created. RESULTS: Using the continuous forms of periodontal measurements, the odds ratios (ORs) (95% confidence interval) of the association with incident MI were 1.46 (1.26 to 1.69), 2.19 (1.66 to 2.89), 1.30 (1.14 to 1.49), and 1.04 (1.02 to 1.07) for mean CAL, PD, ACH, and number of missing teeth, respectively. Regardless of the case definition of periodontal disease, the estimates of the association with incident MI were statistically significant. CONCLUSIONS: The observed association between periodontal disease and incident MI was consistent across different measurements and/or case definitions of periodontal disease used. The magnitude of the association varies depending on the measurements or the criteria used to define periodontal disease.     

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.Key words: Periodontal disease, low birthweight, preterm birth     

Oral Neutrophil Levels: A Screening Test for Oral Inflammatory Load in Pregnancy in a Medical Setting

Background: A multitude of studies suggest an association between periodontal disease and adverse birth outcomes, but the findings have been equivocal. Although the evidence is controversial, it is biologically plausible, and the key link may be inflammation. Because periodontitis is at times either active or inactive, trying to correlate the presence of pockets, for example, to adverse outcome of pregnancy might be preordained to failure or at least confusion. Alternatively, if inflammatory activity associated with periodontitis could be measured, it might be possible to correlate oral inflammatory load (OIL) to adverse pregnancy outcomes more precisely, but given the low incidence of adverse pregnancy outcomes, large populations must be studied. This underscores the need to use a means for assessment of OIL that is reliable, reproducible, and so simple to perform that it does not require dental expertise and can be used for large numbers of patients attending obstetrics units. The objective of this study was to demonstrate that OIL can be measured in a cohort of pregnant females presenting for obstetric care and secondarily to ensure that there was a realistic correlation to the presence of periodontitis. Methods: Sixty‐three pregnant females were recruited, and 15‐second saline rinses were collected to measure OIL as represented by counts of oral neutrophil levels. Periodontal examinations were performed to determine the extent of the correlation between the presence of clinical markers of periodontitis, such as pockets and clinical attachment loss to the OIL. Results: Using this small cohort of patients, a test for oral inflammatory disease could be administered successfully in a non‐dental setting. In addition, there was a statistically significant increase (two‐fold, P <0.05) in oral neutrophil counts found in patients with periodontitis compared with those without periodontitis. Conclusion: The rinse assay can be used as a screening tool for oral inflammation, which was also related to the presence of periodontitis, in pregnant females attending a medical clinic.     

Periodontal diseases and health: Consensus Report of the Sixth European Workshop on Periodontology

Introduction: The remit of this group was to update the knowledge base on periodontal diseases and health.
Material and Methods: The literature was systematically searched and critically reviewed in five specific topics.
Results: Prevalence of periodontitis: The data suggest a trend towards a lower prevalence of periodontitis in recent years.
Adverse pregnancy outcome: The findings indicate a likely association between periodontal disease and an increased risk of adverse pregnancy outcomes. There is no evidence that treating periodontal disease decreases the rate of adverse pregnancy outcomes.
Prevalence and distribution of periodontal pathogens: Genetic analysis of bacteria has demonstrated an unanticipated diversity within species. Carriage rates and particular subsets of these species vary between ethnic groups. Few of these differences can be related to differences in disease prevalence.
Diabetes mellitus: Evidence on the association supports the concept of increased severity but not extent of periodontitis in subjects with poorly controlled diabetes. It is inconclusive that periodontal treatment results in improved metabolic control.
Cardiovascular diseases: Evidence suggests that having periodontitis contributes to the total infectious and inflammation burden and may contribute to cardiovascular events and stroke in susceptible subjects. The impact of periodontal therapy must be further investigated.     

牙周炎与不良妊娠结局相关关系的研究进展

牙周炎是由牙周致病菌感染引起的慢性炎症性疾病,在妊娠妇女中更容易发生。不良妊娠结局是新生儿围产期死亡的重要原因,受机体全身炎症的影响。该文主要对牙周炎与不良妊娠结局的相关性进行阐述,进一步从阴道感染、菌血症、免疫炎症和肠道菌群方面对其机制进行探讨,并简述了牙周炎与不良妊娠结局共有的宿主易感性遗传背景,以期为临床上预防妊娠期牙周病和不良妊娠结局提供一定的理论指导。     

Systemic effects of periodontitis: lessons learned from research on atherosclerotic vascular disease and adverse pregnancy outcomes

Studies conducted over the past 25 years have focussed on the role of periodontitis, an inflammatory condition of microbial aetiology that destroys the tooth‐supporting tissues, as a systemic inflammatory stressor that can act as an independent risk factor of atherosclerotic vascular disease (AVSD) and adverse pregnancy outcomes (APOs). It has been suggested that periodontitis‐associated bacteraemias and systemic dissemination of inflammatory mediators produced in the periodontal tissues may result in systemic inflammation and endothelial dysfunction, and that bacteria of oral origin may translocate into the feto‐placental unit. Epidemiological studies largely support an association between periodontitis and ASVD/APOs, independently of known confounders; indeed, periodontitis has been shown to confer statistically significantly elevated risk for clinical events associated with ASVD and APOs in multivariable adjustments. On the other hand, intervention studies demonstrate that although periodontal therapy reduces systemic inflammation and improves endothelial function, it has no positive effect on the incidence of APOs. Studies of the effects of periodontal interventions on ASVD‐related clinical events are lacking. This review summarises key findings from mechanistic, association and intervention studies and attempts to reconcile the seemingly contradictory evidence that originates from different lines of investigation.     

The relationship between maternal periodontitis, adverse pregnancy outcome and miscarriage in never smokers

BACKGROUND: It has been postulated that associations between periodontal disease and systemic conditions may be because of the confounding effects of smoking. In addition, studies of this type rarely investigate the adverse pregnancy outcome of miscarriage. AIM: The aim of this prospective study was to investigate a relationship between periodontal disease in pregnancy and subsequent adverse pregnancy outcomes in a population of never smokers. MATERIALS AND METHODS: Pregnant women were recruited at 12 weeks gestation. Demographic, behavioural and medical data were collected. A periodontal examination was performed and data on each subjects' pregnancy outcome were collected. RESULTS: A total of 1793 women reported never previously smoking. Of these, 7.3% had a pre-term birth and 0.9% a late miscarriage. As expected in this population, we found no associations between poorer periodontal health and either pre-term birth or low birth weight (LBW). In contrast, the subjects who experienced a late miscarriage had a higher mean probing depth at mesial sites compared with the subjects that gave birth at term (2.69 mm versus 2.41 mm, p=0.006). CONCLUSIONS: There was an association between some measures of periodontal disease and late miscarriage; however, there was no association between periodontitis and pre-term birth or LBW in this population.     

Periodontitis case definition affects the association with renal function in kidney transplant recipients

Oral Diseases (2010) 16 , 636–642 Aim: The aim of this analysis was to investigate the association between periodontal status and renal allograft function in a cohort of renal transplant patients using different periodontitis case definitions. Material and methods: Fifty‐eight kidney transplant patients were included. The subjects were classified into two groups, deterioration or stable/improvement of renal allograft function as expressed by the difference in glomerular filtration rate (GFR) between two time points at least 6 months apart. Chronic periodontitis was defined as: (1) two or more interproximal sites with clinical attachment level (CAL) ≥4 mm or two or more interproximal sites with probing depth (PD) ≥5 mm (DEF1); (2) PD ≥ 5 or CAL ≥ 4 in at least six proximal sites (DEF2); and (3) PD ≥ 5 or CAL ≥ 4 in at least two proximal sites in each quadrant (DEF3). Results: In a multivariate linear regression model, none of the continuous periodontal variables were significantly associated with deterioration of allograft function. Of the three definitions of chronic periodontitis, only DEF2 emerged as significantly more prevalent in subjects with GFR deterioration and was a statistically significant predictor of GFR deterioration over time. Conclusion: These findings underscore the importance of periodontitis ‘case definition’ in the observed statistical associations between periodontitis and systemic disease.     

Change in periodontitis during pregnancy and the risk of pre-term birth and low birthweight

Aim: Determine whether periodontitis progression during pregnancy is associated with adverse birth outcomes.
Methods: We used clinical data and birth outcomes from the Obstetrics and Periodontal Therapy Study, in which randomly selected women received periodontal treatment before 21 weeks of gestation ( N =413) or after delivery (410). Birth outcomes were available for 812 women and follow-up periodontal data for 722, including 75 whose pregnancies ended <37 weeks. Periodontitis progression was defined as 3 mm loss of clinical attachment. Birth outcomes were compared between non-progressing and progressing groups using the log rank and t tests, separately in all women and in untreated controls.
Results: The distribution of gestational age at the end of pregnancy ( p >0.1) and mean birthweight (3295 versus 3184 g, p =0.11) did not differ significantly between women with and without disease progression. Gestational age and birthweight were not associated with change from baseline in percentage of tooth sites with bleeding on probing or between those who did versus did not progress according to a published definition of disease progression ( p >0.05).
Conclusions: In these women with periodontitis and within this study's limitations, disease progression was not associated with an increased risk for delivering a pre-term or a low birthweight infant.     

Maternal chronic infection as a risk factor in preterm low birth weight infants: the link with periodontal infection

In the past decade, there has been mounting scientific evidence suggesting that periodontal disease may play an important role as a risk factor for adverse pregnancy outcomes. This article focuses on the definition, incidence, risk factors associated with preterm low birthweight infants (PLBW), the evidence linking chronic infections and PLBW, and the scientific evidence linking periodontal infections with adverse pregnancy outcomes. Additionally, this review summarizes the current epidemiological studies on the PLBW/infection relation and makes conclusions based on these results. Data from a limited number of studies available support the hypothesis that periodontal disease may act as a risk factor for PLBW infants. The fetal exposure to different periodontal pathogens needs to be confirmed, the mechanisms associated with the potential passage of periodontal bacteria across the placental barrier, and the efficacy of different periodontal treatments in reducing the risk for PLBW need to be studied further.     

Women's Health: Periodontitis and its Relation to Hormonal Changes, Adverse Pregnancy Outcomes and Osteoporosis

Purpose: To examine the literature with respect to periodontitis and issues specific to women's health, namely, hormonal changes, adverse pregnancy outcomes and osteoporosis. Materials and Methods: The literature was evaluated to review reported associations between periodontitis and genderspecific issues, namely, hormonal changes, adverse pregnancy outcomes and osteoporosis. Results: Collectively, the literature provided a large body of evidence that supports various associations between periodontitis and hormonal changes, adverse pregnancy outcomes and osteoporosis; however, certain shortcomings were noted with respect to biases involving definitions, sample sizes and confounding variables. Specific cause and effect relationships could not be delineated at this time and neither could definitive treatment interventions. Conclusion: Future research must include randomised controlled trials with consistent definitions, adequate controls and sufficiently large sample sizes in order to clarify specific associations, identify cause and effect relationships, define treatment options and determine treatment interventions which will lessen the untoward effects on the at-risk populations.     

Role of periodontal therapy in management of common complex systemic diseases and conditions: An update

The goal of this review is to summarize the results of randomized trials reported since 2010 that assessed the effect of periodontal interventions on at least one systemic outcome in human subjects of any age, gender or ethnicity. Oral outcome measures included gingivitis, pocket depth, clinical attachment loss and/or radiographic bone loss and oral hygiene indices. Studies were excluded if the trial was not completed or if treatment was not randomized. The results suggest that nonsurgical periodontal intervention provided to pregnant women is safe and improves periodontal status without preventing adverse pregnancy outcomes. Nonsurgical periodontal intervention was also found to provide modest improvement in glycemic control in individuals with type 2 diabetes mellitus and periodontitis. Also, improving oral care through mechanical or chemical control of dental‐plaque biofilm formation can contribute to the prevention of respiratory infections in differing clinical settings, including hospitals and nursing homes, and in patients with chronic obstructive pulmonary disease. No clinical trials were reported that tested the effect of periodontal interventions on medical outcomes of atherosclerosis, cardiovascular diseases, stroke, rheumatoid arthritis, Alzheimer's disease, chronic kidney disease or malignant neoplasia.     

妊娠晚期孕妇牙周炎与体液中白介素-2含量关系研究

目的 研究妊娠晚期牙周炎孕妇龈沟液、唾液、血清中白介素-2（IL-2）含量变化以及三者间的关联。方法 于2011年4—7月在湖北省妇幼保健院接受口腔检查的妊娠33 ~ 38周单胎孕妇中,随机选取20例牙周炎、26例牙龈炎、22例牙周健康孕妇（对照）纳入研究。分别采集其唾液、龈沟液和血清,采用双抗体夹心ELISA检测IL-2质量浓度。结果 牙周炎组分娩时孕周（36.5 周）明显小于牙龈炎组（38.8 周）和对照组（39.3 周）,牙周炎组分娩时新生儿体重（3079.9 g）低于牙龈炎组（3452.5 g）和对照组（3462.4g）,差异均有统计学意义（均P < 0.05）。牙周炎组大专及以上学历、孕前半年行口腔保健的比例明显低于牙龈炎组和对照组（均P < 0.05）。牙周炎组龈沟液、唾液中IL-2质量浓度明显高于牙龈炎组和正常对照组,差异有统计学意义（均P < 0.05）;但3组血清中IL-2质量浓度比较,差异无统计学意义（P > 0.05）。各组孕妇龈沟液、唾液、血清中IL-2质量浓度之间均两两呈线性相关,差异有统计学意义（均P < 0.01）。结论 妊娠合并牙周炎孕妇口腔中IL-2含量较高,并与血清中IL-2质量浓度呈直线相关,在牙周炎合并不良妊娠结局（如早产、低体重儿等）的发病机制中起一定作用。重视口腔卫生是预防不良妊娠结局的方法之一。     

武汉市1009名孕妇牙周状况调查

目的:了解武汉市孕妇的牙周状况及其影响因素。方法:采用横断面研究的方法,按照纳入标准抽取2006-05—12在省妇幼保健院进行孕检或生产的已作婚姻登记的妇女1009名。调查方法包括问卷调查和临床牙周检查。运用卡方检验及Logistic回归分析的统计学方法对数据进行分析。结果:受检孕妇的牙龈炎和牙周炎患病率分别为74.8%和37.2%。大于30岁者患牙周炎的危险度比值(oddsratio,OR)为1.6;学历较低者患牙龈炎的OR为1.4;月收入为中或低水平的孕妇患牙周疾病的几率较大,牙龈炎OR分别为1.5和2.1,牙周炎OR分别为1.1和1.7;孕前近1年内没有口腔就诊行为的孕妇,患牙龈炎和牙周炎的OR分别为2.3和2.1;孕前或孕期患有全身性疾病的孕妇,患牙龈炎和牙周炎的OR分别为1.8和2.2;孕期有过吸烟和饮酒行为的孕妇患牙周炎的OR分别为3.8和1.6。结论:牙周疾病较易发生于年龄较大、学历和月收入较低、口腔健康行为较差、孕前或孕期患有全身性疾病及有吸烟或饮酒行为的孕妇,应加强对这部分孕妇的口腔健康教育。     

Periodontitis and nosocomial lower respiratory tract infection: preliminary findings

Aim: To evaluate the possible association between periodontitis and nosocomial lower respiratory tract infection (LRTI).
Material and Methods: A case–control study was conducted at a General Hospital in Feira de Santana, Bahia, Brazil. The sample consisted of 103 individuals: 22 cases (presence of nosocomial LRTI) and 81 controls (absence of nosocomial LRTI). The diagnosis of periodontitis was based on probing depth, gingival recession, clinical attachment loss and bleeding on probing. The diagnosis of nosocomial LRTI was made in accordance with established medical criteria.
Results: Invasive ventilation was much more frequent in cases (95.5%) than in controls (7.4%). An orotracheal tube was used in 81.8% of cases and in 7.4% of controls; bronchoaspiration was suspected in 81.8% of cases and in 6.2% of controls. There was no statistically significant difference in any of the clinical periodontal parameters between cases and controls. The crude odds ratio (OR) value for individuals with periodontitis having LRTI was not statistically significant [OR_crude=1.70; 95% confidence interval:(0.60–4.87)]. After including age, smoking and duration of hospitalization in the logistic regression, the adjusted OR for individuals with periodontitis having LRTI was statistically significant [OR_adjusted=3.67 (1.01–13.53); p =0.049].
Conclusions: A marginal association between periodontitis and LRTI was found when smoking, age and length of hospitalization were included as covariates. Patients with LRTI had a high frequency of suspected bronchoaspiration and this could explain the possible association of periodontal disease and LRTI found in this and other studies. Additional studies are needed to further clarify the possible relationship between periodontal disease and LRTI.     

Oral health and adverse pregnancy outcomes - what's next?

Studies on the link between periodontal disease and adverse pregnancy outcome have gone through several phases. The epidemiological studies predominantly support a positive association between these wide-affecting diseases. During the intervention phase, a few small-scale, single-center studies reported improvement of birth outcome following periodontal treatment, whereas the large-scale multi-center studies did not demonstrate efficacy. Many questions arise with regard to patient population, disease type, and therapy. In addressing these questions, it is crucial that one understands the mechanism underlying the link between these diseases. Two non-mutually exclusive hypotheses exist. In the first, periodontal disease is believed to affect the maternal and fetal immune responses systemically, leading to premature labor. Alternatively, evidence is accumulating that oral bacteria may translocate directly into the pregnant uterus, causing localized inflammation and adverse pregnancy outcome in the presence or absence of clinical periodontitis. The oral-uterine transmission is not limited to the well-recognized periodontal pathogens, but instead may also involve the commensal species. Future studies should investigate these mechanisms, to understand the host susceptibility to oral-uterine transmission. Only when a thorough understanding of the mechanism is achieved can meaningful intervention studies be designed utilizing effective therapies, targeting appropriate populations, and measuring relevant outcomes.     

Choosing the left fork: Steven Offenbacher and understanding maternal periodontal disease and adverse pregnancy outcomes

Steven Offenbacher was one of the first researchers to identify periodontal disease as a risk factor for various adverse pregnancy outcomes. Cohort and case-controlled studies of pregnant women have demonstrated periodontal disease as a risk factor for preterm birth, preeclampsia, and fetal growth restriction. Periodontal therapy during the second trimester improves maternal oral health but fails to reduce the risk of preterm birth. A possible association between periodontal disease and gestational diabetes has also been reported. In one model, periodontal bacteria gain access to the systemic circulation, and thereby the placenta, resulting in local inflammation, placental dysfunction, and, consequently, adverse pregnancy outcomes. It is crucial to increase awareness of the links between maternal periodontal and adverse pregnancy outcomes and to promote oral health prophylaxis during pregnancy.     

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

Periodontal diseases and association with atherosclerotic disease

Cardiovascular diseases still account for the majority of deaths worldwide, although significant improvements in survival, after being affected by cardiovascular disease, have been achieved in the last decades. Periodontal diseases are also a common global burden. Several studies have shown a link between cardiovascular disease and periodontitis, although evidence is still lacking regarding the direct cause-effect relation. During the 2012 “Periodontitis and systemic diseases” workshop, the available evidence on the association between cardiovascular and periodontal diseases was discussed, covering biologic plausibility and clinical studies. The objective of the present narrative review was to update the previous reviews presented at the 2012 workshop, following similar methodological approaches, aiming to critically assess the available evidence. With regard to biologic plausibility, two aspects were reviewed: (a) for microbiologic mechanisms, assessing periodontal bacteria as a contributing factor to atherosclerosis based on seven “proofs,” substantial evidence was found for Proofs 1 through 6, but not for Proof 7 (periodontal bacteria obtained from human atheromas can cause atherosclerosis in animal models), concluding that periodontal pathogens can contribute to atherosclerosis; (b) mechanistic studies, addressing five different inflammatory pathways that could explain the links between periodontitis and cardiovascular disease with the addition of some extra pathways , suggest an association between both entities, based on the presence of higher levels of these inflammatory markers in patients with periodontitis and cardiovascular disease, vs healthy controls, as well as on the evidence that periodontal treatment reduces serum levels of these mediators. When evidence from clinical studies was analyzed, two aspects were covered: (a) epidemiologic studies support the estimation that the incidence of atherosclerotic disease is higher in individuals with periodontitis than in individuals with no reported periodontitis, irrespective of many common risk factors, but with a substantial variability in the definitions used in reporting of exposure to periodontal diseases in different studies; (b) intervention trials have shown that periodontal therapy can reduce serum inflammatory mediators, improve the lipids profile, and induce positive changes in other cardiovascular disease surrogate measures, but no evidence is available to support that adequate periodontal therapy is able to reduce the risk for cardiovascular diseases, or the incidence of cardiovascular disease events in periodontitis patients.     

Impact of periodontitis definition in epidemiological research. Results from the EPIPAP study in postpartum women

The purpose of this investigation was to study the impact of using various definitions of periodontitis on the frequency of periodontitis and on the associations with some known risk factors for periodontitis in a population of postpartum women in France. A clinical examination was performed within 2-4 d postpartum in 932 at-term women at five maternity units. We studied six definitions of periodontitis; five were applicable if at least two teeth were found to have the following: (i) a proximal clinical attachment level (CAL) of ≥ 3 mm; (ii) a probing depth (PD) of ≥ 4 mm; (iii) a PD of ≥ 4 mm and a CAL of ≥ 3 mm at the same site; (iv) a proximal PD of ≥ 5 mm or a proximal CAL of ≥ 4 mm; or (v) a PD of ≥ 4 mm and a CAL ≥ 3 mm and bleeding on probing at the same site. The sixth definition required the involvement of four teeth with a PD of ≥ 4 mm and a CAL of ≥ 3 mm at the same site. Associations between case status according to each definition and maternal characteristics (age, educational level, smoking before pregnancy, and time since last dental visit) were analyzed using generalized estimating equation models. The definition of periodontitis had an impact on the frequency of periodontitis, which ranged from 12.1% to 37.7%, and produced different ORs for the associations with risk factors for periodontitis.