Impact of the global burden of periodontal diseases on health, nutrition and wellbeing of mankind: A call for global action

1 Introduction

Periodontal diseases, comprising gingivitis and periodontitis, are probably the most common disease of mankind (Guinness World Records 2001). The recent Global Burden of Disease Study (GBD, 1990–2010) indicates that: (i) severe periodontitis is the 6th most prevalent disease worldwide, with an overall prevalence of 11.2% and around 743 million people affected, and (ii) the global burden of periodontal disease increased by 57.3% from 1990 to 2010 (Jin et al., 2016; Kassebaum et al., 2014a; Marcenes et al., 2013; Murray et al., 2012). As periodontitis is the major cause of tooth loss in adult population worldwide, these individuals are at risk of multiple tooth loss, edentulism and masticatory dysfunction, thereby affecting their nutrition, quality of life and self-esteem as well as imposing huge socio-economic impacts and healthcare costs (Chapple, 2014; Chapple et al., 2015; Petersen & Ogawa, 2012; Pihlstrom, Michalowicz, & Johnson, 2005). Periodontal diseases are responsible for 3.5 million years lived with disability (GBD 2015 Disease and Injury Incidence and Prevalence Collaborators, 2016). The global cost of lost productivity from severe periodontitis alone has been estimated to be 54 billion USD/year, while the total economic impact of periodontal diseases accounts for a major component of the 442 billion USD, direct and indirect cost of oral diseases incurred in 2010 (Listl, Galloway, Mossey, & Marcenes, 2015). The overall prevalence of periodontitis increases with age, and the incidence rises steeply in adults aged 30–40 years. Such burden of periodontitis will continue to increase with the growing ageing population also due to increased tooth retention globally (Jepsen et al., 2017; Kassebaum et al., 2014b; Tonetti et al., 2017). Periodontitis disproportionately affects the vulnerable segments of the population and is a source of social inequality (Jepsen et al., 2017; Jin et al., 2011).

Periodontitis is a chronic non-communicable disease (NCD) that shares social determinants and risk factors with the major NCDs that cause around two-thirds of deaths such as heart disease, diabetes, cancer and chronic respiratory disease (Ezzati & Riboli, 2012; FDI 2013a,b; Jin, 2013; Sheiham & Watt, 2000; United Nations 2011). Tobacco smoking, obesity and poor nutrition (both in terms of caloric intake and quality of the nutritional components) and physical inactivity have all been associated with an increased risk of periodontitis (Chapple et al., 2017). Trends in risk factors are likely to impact the burden of periodontitis, and the rise of smoking in developing countries combined with the obesity/diabetes epidemic will further drive incident periodontitis. Besides the shared risk factors with major NCDs, accumulation of dental biofilms consequent to inadequate self-performed oral hygiene procedures, such as tooth brushing and use of inter-dental cleaning aids, accounts for the initiation and progression of periodontal disease in the population. These biofilms, if not well controlled, interact with the unique susceptibility profile of each individual and may become dysbiotic, thereby initiating and sustaining the disease process which is characterized by the inflammatory destruction of the tooth-supporting apparatus and alveolar bone (Darveau, 2010; Hajishengallis et al., 2011; Kornman, 2008; Sanz et al., 2017). The key presentations of periodontitis in the early stages are gingival bleeding, recession of the gingival margin and halitosis. Measurable changes in oral health-related quality of life are present (Buset et al., 2016; Shanbhag, Dahiya, & Croucher, 2012).

Once a considerable amount of the periodontal attachment has been destroyed by periodontitis both in terms of number of affected teeth and severity, the disease is complicated by an array of signs and symptoms that further impact on the quality of life of the affected individuals. These include tooth migration and drifting, tooth hypermobility, tooth loss and ultimately increasing levels of masticatory dysfunction. Masticatory dysfunction, as the terminal stage of periodontitis, compromises nutrition and general health. However, the early stages of periodontal disease are often symptomless, and a significant number of affected patients do not seek professional care. The relatively “silent” nature of the early stages of the disease, combined with low awareness of periodontal health, leads to many patients seeking “symptom-driven” care for advanced disease through periodontal therapy when available and affordable (Jin, 2015).

Considerable evidence also points to the fact that the effects of periodontitis go beyond the oral cavity and that the body is affected by the haematogenous dissemination of both bacteria and bacterial products originating in the oral biofilms and inflammatory mediators originating in the inflamed periodontium. Through these mechanisms, periodontitis interacts with various systemic diseases, notably diabetes, atherosclerosis, rheumatoid arthritis and pulmonary infections. Loss of masticatory function consequent to periodontal attachment loss and tooth loss due to severe periodontitis impacts on nutrition, as subjects with masticatory dysfunction change their dietary habits usually incorporating more starch and fats and less fresh fruit and vegetables in their diet. The systemic inflammatory burden and poor nutrition consequent to severe periodontitis may contribute to the pathogenesis of chronic NCDs (Tonetti & Kornman, 2013).

Periodontitis can be prevented, easily diagnosed and successfully treated and controlled following appropriate professional care and long-term secondary prevention. Currently, various cultural and socio-economic barriers to professional care prevent the public from applying correct preventive approaches, receiving early diagnosis and seeking treatment, resulting in limited progress in improving periodontal health (Jin et al., 2011). This call for global action aims to draw the attention of oral healthcare professionals, medical practitioners, educators, health officials, payers and the public to opportunities to improve periodontal health and general health. In this document, it is recognized that different countries are at different levels with respect to periodontal health literacy, care and policy. However, even in the most advanced countries, considerable segments of the population continue to present high burdens of disease and have difficulty in accessing health information and professional services.

2 Opportunity 1—Prevention

Prevention is the key for oral health (Editorial, Lancet 2009). Periodontitis is preventable through effective management of gingivitis and promotion of healthy lifestyles at both population and individual levels (Chapple et al., 2015; Jepsen et al., 2017). This can be accomplished through: (i) professional instruction of self-performed effective oral hygiene such as tooth brushing and inter-dental cleaning, and (ii) an integrated and population-based approach in health education based on the Common Risk Factor Approach in the context of the recent UN's resolution for establishment of the 2030 sustainable development goals (GBD 2015 SDG Collaborators, 2016; United Nations, 2015). A critical element is that prevention should be tailored to individual needs through diagnosis and risk profiling. Meanwhile, it is emphasized that each individual should play a proactive role in awareness of oral health, self-care measures, health promotion and disease prevention for optimal oral and general health in the course of life.

Conclusions of the recent European Workshop on Periodontology in primary and secondary prevention of periodontal and peri-implant diseases have helped to identify potential large-scale preventive programmes and highlighted specific actions that may reduce the worldwide prevalence of periodontal diseases (Tonetti, Chapple, Jepsen, & Sanz, 2015). These are the key recommendations.

More information is available in the consensus statements of the four workshop working groups (Chapple et al., 2015; Jepsen et al., 2015; Sanz et al., 2015; Tonetti, et al., 2015).

As common oral diseases like periodontitis share risk factors with other NCDs such as heart disease and diabetes, the Common Risk Factor Approach, strongly advocated by the WHO for improving human health, should incorporate self-performed oral hygiene as one of the positive lifestyles. Preventive programmes for NCDs should thus take into account the specific needs to effectively support oral health as one of the fundamental components of general health (United Nations 2011) and include them in large-scale population efforts whenever feasible. Notably, FDI's new definition of oral health recognizes its multidimensional nature and attributes (i.e. disease status, physiological function and psychosocial function), and promotes incorporation of oral health into the mainstream of health and healthcare for effective advocacy of optimal oral and general health (Glick et al., 2016; Lee, Watt, Williams, & Giannobile, 2017).

3 Opportunity 2—Diagnosis

Periodontitis is easily diagnosed via a full-mouth comprehensive periodontal evaluation. Periodontal probing should be a key component of regular dental visit. Professional periodontal screening approaches that are both sensitive and inexpensive were introduced in several countries more than a quarter of a century ago. Their routine adoption by all oral healthcare professionals has been an elusive objective, and the burden of undiagnosed disease remains high worldwide. Furthermore, diagnosis is frequently delayed until symptoms of advanced periodontal breakdown emerge. Missed or delayed diagnosis often results in very significant increases in both the burden and cost of disease management, and it indeed represents the leading cause of professional litigation in many industrialized countries (Zinman, 2001). Professional organizations around the world recognize the value of a three-step approach to periodontal diagnosis:

Early diagnosis followed by appropriate treatment and secondary prevention has the potential to improve quality of life, preserve teeth and masticatory function, and reduce the lifelong social and financial burden associated with caring for periodontitis.

Periodontal diagnosis should include an assessment of risk factors for periodontitis. As various systemic conditions (e.g. diabetes) interact with periodontitis or its treatment, their screening is part of a standard periodontal examination. Since the adult population in advanced countries is more likely to see an oral healthcare professional than a medical practitioner, screening for and monitoring of conditions such as diabetes, hypertension and obesity in the dental setting may greatly contribute to detection of undiagnosed medical conditions (Genco et al., 2014; Lalla, Kunzel, Burkett, Cheng, & Lamster, 2011). This reshaped and expanded role of oral healthcare professionals would improve patients' oral and general health, while enhancing their roles in the health workforce team (Glick et al., 2012).

It may be useful to stage the extent and severity of periodontitis and the presence of masticatory dysfunction in a given subject, as treatment needs are likely to be different.

Stage 1: Mild to Moderate Periodontitis refers to a condition characterized by gingival inflammation and a degree of destruction of the periodontal attachment compatible with oral function.

Stage 2: Severe Periodontitis refers to a condition characterized by gingival inflammation, advanced destruction of the periodontal attachment and presence of vertical bone defects and/or furcation involvement. Oral function may still be preserved but the risk of disease progression leading to tooth loss is high.

Stage 3: Severe Periodontitis complicated by Masticatory Dysfunction refers to a condition characterized by gingival inflammation, advanced destruction of the periodontal attachment, presence of vertical bone defects and/or furcation involvement, as well as loss of masticatory function consequent to tooth hypermobility and/or tooth loss.

4 Opportunity 3—Treatment

Periodontal treatment aims to control gingivitis and periodontitis, avoid disease progression leading to tooth loss, retain a functional dentition for a lifetime, preserve self-esteem and improve quality of life.

Overwhelming evidence indicates that periodontitis can be treated and effectively managed in the majority of subjects. Long-term studies report that, after periodontal therapy, rate of tooth loss averaging 0.1 tooth/patient/year is observed in subjects participating in professional secondary prevention programmes in specialist practice (Trombelli, Franceschetti, & Farina, 2015). This rate is generally compatible with the preservation of the dentition for a lifetime in the majority of subjects. A systematic review reporting tooth survival up to 22 years after periodontal therapy in specialist practice indicates that tooth loss due to periodontal reasons ranges from 1.5% to 9.8%, while 36 to 89% of treated subjects do not experience further tooth loss (Chambrone, Chambrone, Lima, & Chambrone, 2010). Higher rates of tooth loss were observed among older individuals and smokers.

Delivery of appropriate periodontal care to the individual patient requires a full diagnostic and prognostic assessment of the case and access to effective treatments to control inflammation and avoid tooth loss. Periodontal treatment requires delivery by a highly skilled, and sometime highly specialized oral health care professional. Access to such professionals remains a challenge in many health systems.

Scientific evidence indicates that periodontal treatment consisting of a series of sequential phases of care is effective and that the effectiveness is also related to the skill level and experience of the oral health care professional. These phases are:

A classical study with 30-year follow-up indicates that optimal results are obtained with specialist care followed by participation in secondary prevention programmes in specialist clinics. Failure to deliver structured secondary prevention care in a specialist clinic leads to higher rates of recurrence of periodontitis and tooth loss (Axelsson & Lindhe, 1981; Axelsson, Nyström, & Lindhe, 2004).

Periodontal care is being provided in a variety of health systems around the world and, given the global burden of disease, it requires the active engagement of a highly trained and motivated oral health professional team. As the complexity of treatment increases with disease progression (Stages 1–3 periodontitis), it is important to plan appropriate primary and secondary care in national health systems. Appropriate assessment and enhancement could therefore be performed in every country for optimizing the national oral healthcare strategies and services.

In countries with structured dental services, effective primary care is provided in general dental offices through a dentist-led teamwork with dental hygienists and assistants with clearly defined areas of responsibility. While secondary care is delivered in more specialized centres, usually under the guidance of a specialist. In some countries, tertiary care facilities at academic centres may provide support for the management of unusual and challenging forms of disease.

The remit of primary care facilities comprises periodontal health information, health promotion, instruction in self-performed oral hygiene and preventive care for the general population, diagnosis and monitoring to ensure early detection of periodontitis, effective management of mild and moderate forms of disease (Stage 1 periodontitis), early recognition of subjects responding poorly or incompletely to standard treatment in the primary care setting and consideration of referral to a secondary care facility. Access to specialist care is best performed by referral from a primary care facility but patient self-referral is a possibility. The remit of specialized centres includes the management of more advanced (Stages 2 or 3 periodontitis) or non-responding forms of periodontitis as well as periodontitis in patients with complex medical co-morbidities. In many countries periodontitis management in secondary care facilities is provided under the guidance of a periodontist or periodontologist—a trained specialist.

At these centres patients are given comprehensive advice on the full spectrum of treatment options available for the management of their periodontitis, and they should be able to receive the most appropriate form of treatment including control of advanced periodontitis (Stage 2 periodontitis), access flap surgery, osseous resective or regenerative periodontal surgery to manage deep residual pockets, management of ridge deformities consequent to tooth loss, rehabilitation of masticatory dysfunction with dental implants (Stage 3 periodontitis), management of aesthetic concerns with periodontal plastic surgery and, most importantly, the necessary specialized secondary preventive care tailored for high-risk individuals.

Technological advances over the last decades have considerably improved the applicability and predictability of these procedures, and advanced periodontal therapy is based on the largest body of scientific evidence in dentistry, that is, the references of European Federation of Periodontology (EFP) and American Academy of Periodontology (AAP) workshops. Since the science supporting periodontal treatment is strong, specific actions should address at the national level the following priorities to improve access to the available care:

Clarifications of the above priorities, along with the availability of the necessary resources, may improve access to care and contribute to the management of the current burden of disease.

5 Conclusions

Periodontology is supported by a strong and coherent body of scientific evidence; that allows identification of appropriate preventive, diagnostic and therapeutic strategies to effectively reduce the enormous global burden of disease represented by periodontitis, promote periodontal health, enhance general wellbeing and better manage socio-economic consequences. This call for global action has summarized reasonable strategies and undertakings whose implementation requires consideration of the specific national scenarios in terms of resources and health system model.

Conflict of Interest

Authors report no conflict of interest.