**1. Introduction**

Periodontal disease (PD) is a chronic condition accompanied by a progressive pathogenic biofilm that continuously triggers inflammation, potentially resulting in the loss of both soft and bony periodontal tissues. Ultimately, in severe cases, edentulism may result (**Figure 1**) [1].

Although aspects such as age, genetics, or sex can affect the chance of developing PD, there are also modifiable risk factors that have been identified. That is, smoking, nutrition (e.g., low vitamin D and calcium), and poorly managed diseases (e.g., diabetes, rheumatoid arthritis, and obesity) as well as stress, have also been found to play a significant role in susceptibility [2–4].

According to several epidemiological reports, the prevalence of PD is increasing over time. In fact, current publications indicate that approximately 10% of the global population presents with severe periodontitis, while almost half of the remaining 90% of all adults present with a less severe form of the disease. By and large, the most conservative estimate places the prevalence of PD at approximately 50% of the adult population worldwide [1, 5–7].

**Figure 1.**

*An illustration of a healthy tooth and periodontal tissue (left side) compared to periodontal disease (right side).*

Since people suffering from PD may experience chronic pain and tissue destruction, which can lead to anxiety and depression, the overall loss of quality of life has become an additional area of epidemiological observation. In fact, the deleterious impact of PD on wellness has recently been quantified using the index for Oral Health-Related Quality of Life (OHRQoL) and it was reported that the quality of life significantly decreases proportionally to the severity of PD [8, 9].

Additionally, PD has been found to have a widespread detrimental economic impact. For example, a recent study using accumulated data from the USA and 32 European countries, reported the approximate expenditure due to PD to be \$154.06B in the USA, and 158.64B Euros in Europe [10].

Overall, a body of epidemiological evidence has emerged, reporting the increasing prevalence, economic burden, and diminished quality-of-life for a large enough portion of the global population, that PD has gained attention as growing concern of global proportion.

Although compiled review reports pertaining to the epidemiology of PD have been used as a benchmark, the distinction between gingivitis, mild to moderate PD, and more severe disease forms, has been inconsistent, creating a lack of comparability between and within the various epidemiological demographics [11].

Despite these steps towards unified categorisation, the ability to compare studies may still be diminished by the variation in classification of PD between clinicians and investigators [11–13].

### **2. Other inflammation-mediated conditions associated with PD**

The conflicting reports, regarding the extent and severity of PD in the epidemiological literature, do not change the legitimate growing concern around the prevalence of the disease, especially when one considers the many inflammation-mediated systemic diseases with which it has been associated. For example, several reports indicate that PD can potentially increase the chance of developing heart disease [14–20], neurodegenerative disease [21–23], and autoimmune disease [24, 25] (**Figure 2**).

Further to this, chronic PD has been linked to a range of malignancies [26–30] and respiratory diseases [31–34] (**Figure 2**). Accordingly, the necessity for more ways to effectively prevent, manage, and treat PD, remains paramount.

*Evaluation of Trans-Resveratrol as a Treatment for Periodontitis DOI: http://dx.doi.org/10.5772/intechopen.101477*

**Figure 2.** *An overview of some of the diseases that have been associated with PD.*
