Temporomandibular Joint Disorder from a Perspective of Gerodontology

Abstract

The final years of the current decade (2000-2010), which were dedicated to bone and joint diseases by the World Health Organization, are the right time to pay attention to musculoskeletal diseases of the orofacial system. A basic concept related to TMDs is the attempt to include musculoskeletal disorders of the stomatognathic system into the functional schematics of disorders appearing elsewhere in the body. Apart from the general knowledge on ageing, undergraduate dental students should be taught about anticipating needs, planning and implementing treatment and the subsequent care of the elderly prosthodontic patients. The clinical picture of TMJ functional disturbances may range from physiological variability of joint structures functioning (sometimes painless joint sound) to painful condition with pronounced clinical signs of TMJ disorder.

Keywords: Temporomandibular joint; Education; Elderly; Gerodontology; Magnetic resonance imaging

Abbreviations

CBCT: Cone Beam Computerized Tomography; MRI: Magnetic Resonance Imaging; TMD: Temporomandibular Disorders; TMJ: Temporomandibular Joint

Introduction

Geriatric dentistry was defined as that portion of the dental medicine which deals with special knowledge, attitudes, and technical skills required in the provision of oral health care to older adults [1]. Besides general medicine, Temporomandibular Disorders (TMDs) are an umbrella term for certain myogenic and arthrogenic diagnoses [2,3]. Apart from the teeth and the supporting structures, masticatory muscles and temporomandibular joints are some of the most important parts of the functionally and topographically connected organs and tissues which form the stomatognathic system. Numerous dental branches (periodontology, endodontics, prosthodontic, implant prosthodontics, etc.) have, from a dental perspective, the goal of preserving not only oral health but also general health of the patients [4].

TMDs as the orofacial form of these musculoskeletal disorders are not the most frequent group of diseases in geriatric dentistry practice, unlike problems related to restorative dentistry, especially prosthodontics [5,6]. Musculoskeletal disorders are typical of old age, and there is no doubt that ageing affects the structure and function of Temporomandibular Joints (TMJs) [7]. The final years of the current decade (2011-2020), which were dedicated to bone and joint diseases by the World Health Organization. Musculoskeletal diseases are a public health issue which, in its patient management, also includes gerodontology. Even in the previous decade between the years 2000- 2010 which was dedicated to bone and joint diseases, it was included into the European and Croatian National Action Network [8,9].

The aim of this study was to identify the current status of the relationship between geriatric dentistry and medical disciplines (particularly rheumatology and physical medicine) in the management of TMDs of the elderly.

Geriatric Education Regarding Dental Medicine

It is of importance to motivate students to enable them to work with the elderly, which will eventually provide and improve oral health of the older population [10]. Geriatric educational and research activities in medicine developed during the 1960s and the 1970s. Nordic countries established a collaboration regarding the issues of geriatric medicine through the Nordic Gerontological Federation in 1974 [11]. Almost simultaneously, activities concerning geriatric dentistry were being carried out in the same region of Europe [11,13].

Kossioni et al. [14] stressed that the educational goal of gerodontology is to raise awareness about the barriers to care and to prepare dental students, in terms of knowledge, attitudes, ethics and skills, to provide appropriate oral health care for the older adults. The American Dental Education Association presented (in collaboration with Glaxo Smith Kline) innovative models in geriatric dentistry based on the need for interdisciplinary models and integration with special needs patient care [15].

In some U.S. dental schools, geriatric dentistry courses have been developed within the curriculum [1]. There were no special lectures and courses in Austrian dental schools in 2004. In contrast, it was revealed that a special lecture or practical course in gerodontology has been provided in all Swiss and a few German schools [16]. In the UK, there is a large number of departments which are especially devoted to geriatric or special care dentistry [17]. Japan’s dental educational system is a 6-year undergraduate students’ program of education. In Japan geriatric dentistry is taught in almost a third of the schools at geriatric dentistry departments [18]. Brazil, on the other hand, was the first country to recognize the specialty of geriatric dentistry in 2001 [19]. It is of importance to motivate students to enable them to work with the elderly, which will eventually provide and improve oral health of the older population.

In Croatia, the share of elderly population was 15.62% in 2001 and it grew to 16.64% in 2004 [20]. In Croatia, knowledge on geriatric dentistry, TMDs, and occlusion is a part of dental undergraduate education curriculum. In the year 2008, geriatric dentistry became an obligatory undergraduate course at the Dental Department, School of Medicine, University of Rijeka. At the School of Dental Medicine in Zagreb, geriatric dentistry was an obligatory course until 2005. Since then it has been an elective course for students attending the last semester of their college education. So far, TMDs have not been recognized as special problematic of the elderly population [21].

Rheumatological View on TMJ-disorder

Some describe TMDs as a form of extra-articular rheumatism, which is only partially true. Pain and TMJ function disorder are intra-articular problems. Inflammatory rheumatic diseases – most often rheumatoid arthritis – are present in 1.5% of women and 0.5% of men of active working population. These percentages of the causes of rheumatic disturbances and/or TMJ diseases can be expected to potentially increase with age, thus multiplying physiatric treatments [22]. On the other hand, osteoarthritis is a low-inflammatory arthritic condition that results in various degenerative joint changes clinically manifested as joint crepitation, arthralgia, and limited opening of the mouth [23]. Radiologically supported studies showed a controversy with respect to the relationship with disc displacement without reduction and clinical and radiological confirmed signs of osteoarthritis of TMJ [24,25].

The effects of osteoporosis, the most common rheumatologicmetabolic disease of our times, on the stomatognathic system are mostly related to pathologic changes on the periodontium of preserved teeth and the edentulous residual ridge. Osteoporosis is one of the major health problems affecting middle-aged and older individuals, especially women. It is associated with several risk factors. Some of them, such as age, smoking, sex, systemic diseases, medications and genetic factors are common for periodontal disease [26]. Osteoporosis affects 10-15% of European Caucasian population. In Croatia, 15% of postmenopausal women have osteoporosis and 30% have osteopenia. Osteoporosis should always be kept in mind since its relation to the development of osteoarthritis has not been fully explained, including the TMJs [27,28].

Concept of TMD

A basic concept related to TMDs is the attempt to include musculoskeletal disorders of the stomatognathic system into the functional schematics of disorders appearing elsewhere in the body. On the contrary, for example, the Gnathologic School and their concepts of etiopathogenesis related to occlusion-TMJ-masticatory muscles did not accept diagnostic methodology and systems of classification applied to other musculoskeletal systems in the body. Traditional dental diagnostics combined with secondary data gathering about the oral status did not provide useful information [29].

Diagnostics of TMDs are based on a standardized clinical examination. The Diagnostic Criteria for TMD as a diagnostic system has become standard in scientific studies, wherein the clinical term TMDs has been divided into separate diagnoses [30]. Thus, there is a distinction between a muscular disorder and TMJ disorder: osteoarthritis and anterior disc displacement. However, the generally accepted terminology does not explain all clinical aspects of temporomandibular pain as the most important clinical sign and symptom of the illness [31].

Understanding biomechanics enables the examination of anatomic structures of TMJ using procedures wherein the patient actively (dynamic compressions and translations) and passively (passive compressions) performs mandibular movements. The psychological factor in musculoskeletal diseases, differential diagnosis of orofacial pain and chronic systemic diseases and the medications used in treatment should be taken into account [33].

Radiolog of TMJ

Magnetic Resonance Imaging (MRI) is the gold standard of radiological diagnostics, a non-invasive and non-ionizing examination of soft and hard TMJ tissues (Figure 1a). Imaging of both the articular disc and the most common type of discopathy, i.e., anterior disc displacement, is the greatest achievement in the field of x-ray radiological methods [34,35]. Another important TMJ pathology is the occurrence of more or less expressed collection of exudates within a relatively small intraarticular space [36]. The most common radiological method of jaw, teeth and TMJ imaging is the panoramic radiogram (Figure 1b).

    

    

    Figure 1:  The same left temporomandibular joint of a 62-year-old female patient with osteoarthritic changes on mandibular condyle (arrow with 1), anterior disc
displacement (arrow with 2) and effusion (arrow with 3) imaged with various radiological modalities: a – magnetic resonance imaging (T1-weighted image), b –
magnetic resonance imaging (STIR sequence), c – temporomandibular joint view on orthopantomogram, d – cone beam imaging (left reconstruction in parasagittal
section), and e – cone beam imaging (three-dimensional reconstruction).