Practitioner, Researcher & Health advisor, India
Received Date: 27/08/2020; Published Date: 25/09/2020
*Corresponding author: Akhil K Padmanabhan, Practitioner, Researcher & Health advisor, India
Sexual health is as important as the overall health. In the modern lifestyle, sexual health problems have become a common issue among the general population. Most of the disorders have unidentified etiologies which makes them difficult to treat. Erectile dysfunction is such a disorder that affects a greater population. As the connection between systemic health and oral health have been investigated over time, the link between the two have started getting clearer. Oral health has been studied to be associated with a wide range of systemic diseases. This review is an attempt to summarize the evidence and mechanisms proposed to establish the link between erectile dysfunction and oral health.
Keywords: Erectile dysfunction; Oral health; Periodontitis; Sexual disorders; Health
Oral health is the reflection of systemic health. This relationship of oral health with the overall health have been identified and studied ever since the origin of dental medicine. Infectious disease of the oral cavity has the potential to cause damage and infection to other parts of the body as explained by focal infection theory . Oral cavity is a favourable situation for several infections such as periodontitis. Periodontitis is the most common infectious and inflammatory disease of the oral cavity. Erectile dysfunction is a sexual disorder characterized by the inability to attain and maintain an erection during sexual activity . It is more common in men above 40 years of age . Several factors such as neurogenic, cavernosal, psychological, hormonal and drugs are studied to cause ED , however, the most commonly explained pathophysiology is vascular disease .
Chronic periodontitis and Erectile dysfunction share certain common risk factors [6-8]. Several studies were conducted to understand the association between these two disorders. A study by Zadik et al.  concluded that chronic periodontitis was found significantly higher among men with ED than without ED. Study by Sharma et al.  failed to detect any association between the two. Inconsistent evidence on the relationship between the two conditions have always left us with an increased need for further studies in this area.
Penile erection during sexual stimulation is achieved by the relaxation of penile arteries and smooth muscles, leading to increased blood flow to the organ. This is mediated by chemicals such as NO (Nitric Oxide) and cGMP. Cyclic GMP causes smooth muscle relaxation and increased blood flow into the corpus cavernosum, and is degraded by specific phosphodiesterase type 5 (PDE5) located around the penis . When there is a blockage of blood flow to the penis due to any reason, the erection fails to happen. Sometimes the individual achieves an erection but fails to maintain it. ED is today considered to be a disease of vascular etiology .
Endothelial dysfunction is a common manifestation of the systemic effects of periodontal diseases. This refers to various pathological conditions, such as alteration in anticoagulant and anti-inflammatory features of the endothelium, vascular growth impairment, and altered vascularremodelling. A combination of endothelial dysfunction and inflammation leads to serious disorders such as atherosclerosis. This blockage of the arteries and capillaries or smooth muscle relaxation may result in the ED . Endothelial dysfunction is the most studied feature and characteristic od ED. Men with endothelial dysfunction are said to present with ED . The penile vasculature is small and atherosclerosis may begin essentially in small vasculature and gradually shifts to larger vasculature. Advanced age is a strong predictor of endothelial dysfunction and ED in elderly patients . Ageing males are at increased risk for ED and the cause for inflammation leading to endothelial dysfunction can be many, such as hypertension, stress, smoking and others.
The cytokines that are commonly involved in periodontal disease are IL- 1, IL- 6and TNF- α. A significant increase in the risk for developing endothelial dysfunction resulting in ED may be associated with high levels of inflammatory mediators such as interleukin (IL)-6, IL-8, tumour necrosis factor-alpha (TNF-α), and IL-1 [15,16]. Among all the cytokines, TNF- α plays a major role in causing ED . Periodontitis also induces local and systemic elevation of proinflammatory cytokines, such as TNF-α, IL-1 and IL-6 [18,19]. Furthermore, multiple studies have shown a reduction in TNF-α levels after successful periodontal treatment [20,21]. It has also been reported that, significant higher plasma levels of TNF-α were associated with moderate to severe ED [22,23] thus explaining their role in maintenance of healthy vasculature  (Figure 1).
Endothelial dysfunction due to inflammatory changes will cause release of reactive oxygen species (ROS) . Increased production of ROS will increase the inactivation in nitric oxide (NO). NO is an important chemical that mediates penile erection. The damage to the antioxidant system may worsen the endothelial dysfunction. Furthermore, an animal study on rat model demonstrated that the periodontitis-induced mild systemic inflammation resulted in reduced expression and activity of endothelial Nitric Oxide synthase in penile tissues [26,27]. The effective management of ED should involve examination for all of these factors in consult with a urologist.
Figure 1: Mechanisms by which periodontitis can cause ED.
Oral health has several systemic associations. The relationship of periodontal diseases to ED is confirmed by short term studies, but longitudinal studies are required to establish a powerful link between the two. However, maintenance of oral hygiene and periodontal treatment has to be emphasized in patients with ED.