Neck Solutions Blog

Prevalence of temporomandibular disorders in a population of complete denture wearers

Gerodontology. 2011 Nov 2. [Epub ahead of print]

Prevalence of temporomandibular disorders in a population of complete denture wearers. Complete tooth loss among the elderly is still frequent in developing countries and the incidence of temporomandibular disorders is a common finding in complete denture wearers. The aim of this study was to evaluate the prevalence of temporomandibular disorders in a population of complete denture wearers. The data were collected by four examiners for the diagnosis of use and need for complete dentures followed by the World Health Organization standards and interviews for temporomandibular disorders signs and symptoms evaluation. Exploratory variables included demographic, socio-economic status and temporomandibular disorders prevalence.

The prevalence of temporomandibular disorders among denture wearers was 55.12%. Chi-squared test showed no statistical difference between subjects with or without temporomandibular disorders for gender, geographical location and skin colour. The number of subjects with temporomandibular disorders increased as the period of complete denture wear increased, although no statistical difference between groups were found. There is a need of educational programmes aiming at the importance of health care and periodical change of a complete denture, and strategies with a preventive approach to quality general dental care.

Signs and symptoms of temporomandibular joint disorders related to the degree of mouth opening and hearing loss.

From: BMC Ear Nose Throat Disord. 2011 May 25;11(1):5.

The temporomandibular joint is critical for normal mouth function, and thus plays a role in chewing, swallowing, speaking, oral health and nutrition. The temporomandibular joint is a synovial joint containing an articular disc which allows for hinge and sliding movements. The articular surfaces are covered by avascular andnon-innervated fibrocartilage which has a high regenerative capacity. The temporalis and masseter muscles control the joint’s motion.

The term temporomandibular disorders is a collective one, representing a sub-classification of muscle-skeletal disorders, and more specifically a number of signsand symptoms involving the masticatory muscles, the temporomandibular joint and associated structures. It is estimated that about one third of adults have temporomandibular disorders symptoms. Temporomandibular disorders has been related to stress, age, gender, personality and other systematic factors.

The maximum mouth opening distance is a generally accepted measurement to estimate temporomandibular joint mobility and function. Mouth opening can be measured using gauges or calipers, and while the normal range differs between populations, the critical functional opening is 35-40mm.

Aural symptoms such as tinnitus, otalgia, dizziness or vertigo, otic fullness sensation, hyperacousia or hypoacousia are thought to be associated with temporomandibular disorders, while their incidence reaches 85% in temporomandibular disorders patients. A causative role of temporomandibular disorders in otic symptomatology remains a matter of debate. Several studies have shown that aural symptoms may have no otic origin. Theories on the etiology of aural symptoms are based mainly on the common embryologic origin of the temporomandibular joint and the middle ear from Meckel cartilage, the presence of structures that connect the middle ear with the temporomandibular joint and the common innervation of the masticatory muscles and the ear.

(more…)

Chewing in temporomandibular disorder patients: an exploratory study of an association with some psychological variables

From: J Orofac Pain. 2011 Winter;25(1):56-67.

To compare kinematic parameters (ie, amplitude, velocity, cycle frequency) of chewing and pain characteristics in a group of female myofascial temporomandibular disorder patients with an age-matched control female group, and to study correlations between psychological variables and kinematic variables of chewing.

Twenty-nine female participants were recruited. All participants were categorized according to the Research Diagnostic Criteria for temporomandibular disorder (RDC/temporomandibular disorder) into control (n = 14, mean age 28.9 years, SD 5.0 years) or temporomandibular disorder (n = 15, mean age 31.3 years, SD 10.7) groups. Jaw movements were recorded during free gum chewing and chewing standardized for timing. Patients completed the Depression, Anxiety, and Stress Scales (DASS-42), the Pain Catastrophizing Scale (PCS), the Fear of Pain Questionnaire-III (FPQ-III), and the Pain Self-Efficacy Questionnaire (PSEQ). Statistical analyses involved evaluation for group differences, and correlations between kinematic variables and psychological questionnaire scores (eg, depression, anxiety, stress) and pain intensity ratings.

Velocity and amplitude of standardized (but not free) chewing were significantly greater in the temporomandibular disorder group than the control group. There were significant positive correlations between pain intensity ratings and velocity and amplitude of standardized chewing but not free chewing. There were significant positive correlations between depression and jaw amplitude and stress and jaw velocity for standardized but not free chewing.

This exploratory study has provided data suggesting that psychological factors, manifesting in depression and stress, play a role in influencing the association between pain and motor activity.

Revision of the American Association of Dental Research’s Science Information Statement about Temporomandibular Disorders

From: J Can Dent Assoc. 2010 Oct;76:a115

Despite continuing research, which is providing an increasing evidence base, the dental profession still does not have a standard of care for diagnosing or managing temporomandibular disorders. Although guidelines have been published by organizations including the American Academy of Orofacial Pain and the American Academy of Oral Medicine, which has published a handbook for managing various orofacial conditions causing pain, these are not officially recognized as authoritative documents by national associations. The Canadian Dental Association and American Dental Association have not established clinical guidelines for this segment of dental practice. To our knowledge, the only North American dental organization that has published temporomandibular disorder guidelines—in 1999, revised in 2009—is the Royal College of Dental Surgeons of Ontario.

In 1996, the American Association of Dental Research published a science information statement on temporomandibular disorders, based on recommendations submitted by its Neuroscience Group. This document, which was based on evidence at that time, provided guidelines for the diagnosis and management of temporomandibular disorders. In 2010, the statement was revised in light of continuing research and the strengthened evidence base. After a broad literature review by the American Association of Dental Research’s Neuroscience Group and a lengthy process of administrative review and revision, the updated official American Association of Dental Research temporomandibular disorder statement was approved in March 2010.

The American Association of Dental Research recognizes that temporomandibular disorders encompass a group of musculoskeletal and neuromuscular conditions that involve the temporomandibular joints, the masticatory muscles, and all associated tissues. The signs and symptoms associated with these disorders are diverse, and may include difficulties with chewing, speaking, and other orofacial functions. They also are frequently associated with acute or persistent pain, and the patients often suffer from other painful disorders (comorbidities). The chronic forms of temporomandibular disorder pain may lead to absence from or impairment of work or social interactions, resulting in an overall reduction in the quality of life.

(more…)