Apical Periodontitis, a Predictor Variable for Preeclampsia: A Case-control Study Navid Khalighinejad, DDS, Anita Aminoshariae, DDS, MS, James C. Kulild, DDS, MS, and Andre Mickel, DDS, MS Abstract Introduction: Preeclampsia (PE) is characterized by hy- pertension and proteinuria after the 20th week of gesta- tion. There is an association between systemic inflammation and adverse pregnancy outcomes such as PE. Therefore, for the first time, the present study aimed to investigate the possible association between maternal apical periodontitis (AP) and PE. Methods: In this case-control study, 50 mothers who were diag- nosed with PE during pregnancy were included in the experimental group. The control group consisted of 50 matched mothers with a normal course of pregnancy. The endodontic and periodontal status of all participants was reviewed using the digital panoramic radiographs that were available before pregnancy. The number of re- maining teeth and the presence of AP in all teeth and endodontically treated teeth were recorded using the periapical index. Binary logistic regression was used to determine the possible association between AP and PE (a = 0.05). Results: AP in at least 1 tooth was found in 27 of the mothers who developed PE (54%) and in 16 of the control patients (32%) (odds ratio [OR] = 2.4, P < .05). Adjusted for the maternal periodontitis, number of teeth, and endodontic treatment, maternal AP was significantly associated with the occurrence of PE (P < .05; OR = 2.23; 95% confidence interval, 95% = 1.92–6.88). Conclusions: AP was significantly more prevalent in the experimental group. For the first time, this study has provided evidence that maternal AP may be a strong independent predictor of PE. Consid- ering the high occurrence of PE, particularly in devel- oping countries, it could be suggested that the risk of PE may be reduced through comprehensive dental ex- aminations for detecting and treating any source of inflammation, including AP, before pregnancy. (J Endod 2017;-:1–4) Key Words Apical periodontitis, association, endodontics, pre- eclampsia, root canal treatment, systematic diseases A pical periodontitis (AP) is the inflammation and destruction of periradicular tissues after an endodontic infection (1). Systemic elevation of proinflamma- tory cytokines such as interleukin (IL) 1 beta, IL-6, and tumor necrosis factor alpha has been shown to be a result of AP (2). This elevated level of inflammatory cytokines may exert a systemic effect on the host, which could explain the possible association between AP and various systemic issues such as diabetes and cardiovascular and renal diseases (3). Periodontal diseases have been shown to burden pregnant patients with systemic inflammatory stressors at the maternal-fetal interface. This burden may result in adverse pregnancy outcomes (4). Also, AP and periodontal disease share similar inflammatory responses (5). Therefore, there might be an association between AP and adverse preg- nancy outcomes. However, this association has never been investigated. One of the most common adverse outcomes of pregnancy is preeclampsia (PE) (6). PE is characterized by hypertension and proteinuria after the 20th week of gesta- tion (7) and is among the leading causes of maternal mortality (6). Approximately 15%–20% of all preterm births are attributed to PE (7). Therefore, identifying possible predictor factors before and during prenatal care is important in the prevention and control of PE. AP may contribute to a systemic immune response that is not confined to a local- ized lesion (2). Considering the fact that there is an association between systemic inflammation and adverse pregnancy outcomes such as PE (8), for the first time, this study aimed to investigate the association between the presence of maternal AP before pregnancy and the risk of developing PE. Materials and Methods Study Design A pair-matched case-control study was performed from January 2014 to January 2016 in the maternity department. An explanation regarding the study was provided to all the participants, and informed consent was obtained. The protocol of the present study was approved by the Committee on Research Involving Human Subjects at Case Western Reserve University, Cleveland, OH. Patient Selection The present study gathered information regarding all childbirths that took place in the maternity center during the study period. These childbirths were limited to mothers who attended the maternal program in the hospital before pregnancy. Per hospital From the Department of Endodontics, Case Western Reserve University, School of Dental Medicine, Cleveland, Ohio. Address requests for reprints to Dr Anita Aminoshariae, Case School of Dental Medicine, 2123 Abington Road A 280, Cleveland, OH 44106. E-mail address: Axa53@ case.edu 0099-2399/$ - see front matter Copyright ª 2017 American Association of Endodontists. http://dx.doi.org/10.1016/j.joen.2017.05.021 Significance This study for the first time has provided evidence that maternal apical periodontitis may be a strong independent predictor of PE. Clinical Research JOE — Volume -, Number -, - 2017 Apical Periodontitis 1