Journal of Diabetes Mellitus, 2016, 6, 209-229 http://www.scirp.org/journal/jdm ISSN Online: 2160-5858 ISSN Print: 2160-5831 DOI: 10.4236/jdm.2016.64024 September 13, 2016 Diabetes and Periodontal Diseases: An Established Two-Way Relationship Carlos Arana Molina 1* , Luna Florencio Ojeda 1 , María Sevillano Jiménez 1 , Cristóbal Morales Portillo 1 , Isabel Serrano Olmedo 1 , Tomás Martín Hernández 1 , Gerardo Gómez Moreno 2 1 Department of Endocrinology and Nutrition, Virgen Macarena University Hospital, Seville, Spain 2 Department of Special Care in Dentistry, Pharmacological Research in Dentistry Group, Faculty of Dentistry, University of Granada, Granada, Spain Abstract Background: Periodontal diseases (PD), including periodontitis, are chronic inflam- matory pathologies caused by bacteria in the subgingival biofilm which affect the periodontal tissues. PD is now considered a localized, chronic, oral infection that activates the host immuno-inflammatory responses both locally and systemically, and also constitutes a source of bacteraemia. It is a known fact that periodontal diseases exercise an important influence on the pathogenesis of numerous systemic diseases, including diabetes mellitus (DM). In the mid-nineties, sufficient scientific evidence emerged to confirm an association between DM and periodontitis, which then began to be regarded as the sixth complication of DM. Current scientific evidence points to a two-way relationship between DM and periodontal disease, whereby DM is associated with an increase in the incidence and progression of periodontitis, while periodontal infection is associated with worsening glycemic control in diabetic patients. This two-way relationship points to a need to promote oral health in DM patients, and to implement a joint management protocol between endocrinologist and dentist that aims to create adequate conditions for early diagnosis and the effective treatment of both diseases. Keywords Diabetes Mellitus, Periodontitis, Periodontal Medicine, Two-Way Relationship 1. Introduction Diabetes mellitus (DM) covers a group of metabolic diseases characterized by hyper- glycaemia caused by defects in insulin secretion, insulin action, or both. The latest research by the International Diabetes Federation (IDF) states that 8.8% of adults (415 How to cite this paper: Molina, C.A., Oje- da, L.F., Jiménez, M.S., Portillo, C.M., Ol- medo, I.S., Hernández, T.M. and Moreno, G.G. (2016) Diabetes and Periodontal Dis- eases: An Established Two-Way Relation- ship. Journal of Diabetes Mellitus, 6, 209- 229. http://dx.doi.org/10.4236/jdm.2016.64024 Received: August 21, 2016 Accepted: September 10, 2016 Published: September 13, 2016 Copyright © 2016 by authors and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access