Temporomandibular Disorders of Iatrogenic Etiology

*Oleg Slesarev*

## **Abstract**

Temporomandibular disorder (TMD) is a heterogeneous chronic systemic disease based on genetic, immunological, anatomical, morphological, and functional disorders of the articulatory norm. The task of the diagnostic stage is to identify direct (inherent in only one nosological form) and indirect (occurring in two or more nosological forms) etiological risks that transform into pathogenetic factors and TMDs. The transformation of the pathogenetic horizon of TMDs does characterize by the implementation of a scenario leading to the formation of three nosological forms of the disease: articular and nonarticular lesions of TMJ, and TMDs of iatrogenic etiology. TMDs of iatrogenic etiology constitute the most severe group of patients. Failure to identify biological, technological, and communication iatrogenic risks at the diagnostic stage is the main reason for triggering TMDs of iatrogenic etiology. The transformation of iatrogenic risks into iatrogenic pathogenetic factors leads to the formation of iatrogenic disease. A specialist working with this group of patients must have the necessary competence to make clinical decisions in the diagnosis, treatment, and rehabilitation of patients of this profile, including maxillofacial surgery and psychological counseling. Timely diagnosis of iatrogenic risks is the only preventive measure that prevents the development of iatrogenic TMDs. The therapy of TMDs of iatrogenic etiology does base on an interdisciplinary approach's principles.

**Keywords:** temporomandibular disorders, iatrogenic TMDs, pathogenesis of TMDs, diagnosis of TMDs

## **1. Introduction**

Temporomandibular disorders (TMDs) are a group of common non-odontogenic maxillofacial pain syndromes. TMDs are the second most common musculoskeletal disorder resulting in pain, dysfunction, and disability [1]. Epidemiological studies have identified problems associated with TMDs in 25% of the population [2, 3], but only 3–7% of patients seek help [4, 5]. In 70% of cases, the reasons for patients visiting the dentist do associate with pain, impaired movements of the lower jaw, and anatomical and functional changes in the temporomandibular joint [6, 7], which is 3.9% of annual visits from the total number of patients with different profiles [8]. Women, in relation to men, present complaints ranging from 2:1 to 8:1 [9–13]. The multifaceted specific picture of the manifestation of the disease leads to incorrect routing of patients, errors in diagnosis and treatment, and chronicity of the TMJ [3, 14–16].

The frequency of severe disorders accompanied by headache and facial pain and characterized by the urgent need for treatment is 1–2% in children, about 5% in adolescents, and 5–12% in adults [17, 18].

Fifty-eight percent of those who consulted a doctor had a history of 3–5 years, and 16% of them reported no positive response to conservative treatment, resulting in 30–40% of acute cases becoming chronic [19]. The average duration of TMJ was 4.19 years and 5.25 2.91 years, respectively, which characterizes TMJ as a heterogeneous chronic systemic disease. The reasons for the duration of the disease indicate either the lack of treatment due to an undetermined diagnosis or unsuccessful observation by a neurologist for trigeminal neuritis or by an otorhinolaryngologist for otitis media [20–23]. In addition, the disease's symptoms may do associate with centrally mediated and neuroplastic changes in the brain, including dysfunction of the endogenous μ-opioid receptor, one of the central analgesic systems involved in pain perception and analgesia [24].

The prevalence of the analyzed disorders, multifactorial pathogenesis, and therapeutic difficulties in the treatment of TMJ prompted Wieckiewicz et al. [25] to make an effort to describe and systematize current TMJ therapeutic concepts based on DC/TMJ data [26]. Treatment of TMJ is complex and requires special knowledge and skills, and to justify the treatment protocol, it is necessary to formulate a diagnosis that takes into account an interdisciplinary approach [27–29], but most patients seeking help due to TMJ symptoms assess that the treatment has episodic success [23, 30]. A meta-analysis showed that 16% of adults require treatment for TMJ [31]. Moreover, those in need of treatment can divided into those who are indicated for active therapy to eliminate severe symptoms and those who require passive supervision. Manfredini et al. [32] conclude that the specialist treating TMDs must, first of all, be able to differentiate between these two groups of patients. For patients requiring treatment for the symptoms of TMDs, it has been found that noninvasive methods should be preferred. However, the complex structure of TMJ, along with the debilitating nature of the disease at an advanced stage, poses challenges for the development and application of more invasive methods of resolution [19, 33–35].

Murphy [3] analyzed the currently used non-invasive, minimally invasive and fully invasive methods of TMJ treatment, where TMJ disorders are the leading symptom [36]. The ultimate goals of the presented modalities are


The successful management of temporomandibular disorders depends on identifying and controlling the contributing factors, including occlusal abnormalities, orthodontic treatment, bruxism and orthopedic instability, macrotrauma and microtrauma, factors like poor health and nutrition, joint laxity, and exogenous estrogen [17, 28].

Global review of research findings by Harper et al. [37] revealed a focus of the flow of clinical diagnostic data in line with the substantiation of two interrelated areas of TMJ therapy: (1) minimization of pain in the maxillofacial region, which is generated and maintained by sensitization mechanisms in the central nervous system; and (2) the need for personalized medicine in providing care to this category of patients.

However, the approach to treating TMDs as a purely dental problem may fail, as a significant proportion of symptoms reflect medical conditions [25, 38], including

*Temporomandibular Disorders of Iatrogenic Etiology DOI: http://dx.doi.org/10.5772/intechopen.104479*

iatrogenic TMDs [8, 39–41]. Sharma et al. [17] identified factors that increase the risk of temporomandibular disorders are called "Predisposing factors" and those causing the onset of temporomandibular disorders are called "Initiating factors" and factors that interfere with healing or enhance the progression of the temporomandibular disorder are called "Perpetuating factors." Iatrogenic injuries can act as both initiating and predisposing factors. This can occur during any dental procedure in which there is early opening like orthodontic treatment, single-sitting root canal treatment, or relapse, which causes a functional imbalance between the temporomandibular joints, muscles, and occlusion. To avoid this damage to the temporomandibular joint, we should always examine the joint [17]. Determining the features of the pathogenesis of TMDs of iatrogenic etiology is a demanded necessity to treat these disorders and for expert evaluation in the event of doctor–patient conflicts. The formation of iatrogenic TMDs proceeds in several stages. The characterization of iatrogenic TMDs as a multistep process made it possible to identify iatrogenic risks triggering the process of iatrogenesis. Timely identification of iatrogenic risks will prevent the development of the disease along the iatrogenic pathway. Disclosure of the stages of iatrogenesis will make it possible to form the principles of diagnosis and treatment of TMDs within the DC/TMD methodology [42–44].
