Functional disorders of the masticatory system. I. Distribution of symptoms according to age and sex as judged from investigation by questionnaire

The 50 most-cited articles on temporomandibular disorders: A bibliometric analysis

BACKGROUND

Temporomandibular disorders (TMD) are musculoskeletal conditions involving masticatory muscles and temporomandibular joints. Bibliometric analysis has been introduced as a new method for collecting and analyzing information on scientific articles.

OBJECTIVE

The aim of this study was to identify the 50 most cited articles on TMD, performing a bibliometric analysis of the identified papers to favor research and clinical practice.

METHODS

On December 17, 2021 a systematic research was performed to find all papers on TMD published in the literature. The Incites Journal Citation Reports dataset and Scopus database was used to obtain bibliometric indexes of the authors and metrics data of the journals, including Impact Factor, Eigenfactor Score, and Normalized Eigenfactor. VOSviewer was used to visualize the keyword mapping networking, with the nodes standing for keywords and the edges for keyword relationships.

RESULTS

Out of 24372 papers obtained by the search strategy, the 50 most cited articles on TMD were analyzed. The paper with the highest number of citations (n= 3020) was on TMD research diagnostic criteria. Rate of citations per year collected by the 50 most cited articles on TMD has been increasing over time (from 627 in 2006 to 1483 in 2021). Most of them were cross-sectional studies (n= 20; 40.0%) and narrative reviews (n= 14; 28.0%).

CONCLUSION

This bibliometric study showed an increasing number of citations for articles on TMD, testifying a high interest in the last years. Starting from this analysis, future studies might provide high-quality evidence on TMD management.

Orthodontic retreatment of an adult woman with mandibular backward positioning and temporomandibular joint disorder: A case report

BACKGROUND

The role of occlusal factors on the occurrence of temporomandibular joint disorders (TMDs) is still unclear and it is tricky for orthodontists to treat malocclusions in patients with TMDs. We report the case of the second orthodontic treatment of an adult female with Class II division 2 malocclusion associated with TMD. With the removal of anterior occlusal interference, TMD symptoms were alleviated and cone beam computed tomography (CBCT) images showed the bilateral condyles shifted forward.

CASE SUMMARY

This case report presented an orthodontic retreatment of an adult female with TMD and mandibular backward positioning based on CBCT examination and Joint Space Index (JSI) analysis. The left and right JSI values of -38.5 and -52.6 indicated that the position of bilateral condyles had posterior displacement. Ten years prior to this evaluation, she underwent orthodontic treatment resulting in the extraction of two upper premolars and one lower central incisor. The joint symptoms, including pain and sounds, were alleviated along with verified mandibular forward repositioning by extraction of another lower central incisor.

CONCLUSION

Mandibular backward positioning could be associated with TMD. JSI analysis based on CBCT is a convenient way to examine condylar positions quantitatively.

Temporomandibular joint innervation: Anatomical study and clinical implications

BACKGROUND

Temporomandibular disorders and related pain are commonly seen in clinical practice. Due to its recurrent nature, they adversely affect a patient's social life. Current knowledge on the temporomandibular joint (TMJ) innervation is debatable and insufficient to ensure optimal treatment for the underlying pathology. This study aimed to elucidate the pathophysiology of temporomandibular pain by revealing the TMJ innervation topography, its variations, and its relationships with the surrounding anatomical structures. This will aid in creating a guide for temporomandibular, infratemporal, and preauricular interventions.

METHODS

A total of 20 cadaver half heads, 10 fresh frozen and 10 embalmed, were used. The TMJ nerves were dissected together with the surrounding anatomical structures.

RESULTS

We showed that the TMJ is mainly innervated by the auriculotemporal nerve posteriorly, the masseteric nerve anteriorly, the posterior deep temporal nerve anteromedially, and the TMJ branch originating directly from the mandibular nerve medially, and that there are variations in these innervation pathways. Additionally, we emphasized how these nerves might be affected in certain clinical conditions based on their anatomical relationships and pathophysiological mechanisms. To our knowledge, this is the first study showing the existence of a branch of the mandibular nerve directly innervating the TMJ.

CONCLUSION

In light of our findings, elucidating TMJ pain based on the anatomical characteristics of the region will allow precise treatment algorithms and better clinical outcomes in these patients. Based on this study, new clinical studies and interventions can be designed to reduce healthcare costs and alleviate the burden of temporomandibular disorders.

Effect of night dentures on tooth mobility in denture wearers with sleep bruxism: a pilot randomized controlled trial

PURPOSE

The purpose of this study was to investigate the inhibitory effect of night denture (ND) placement on abutment tooth mobility in removable partial denture (RPD) wearers with sleep bruxism (SB).

METHODS

The participants were selected from RPD wearers diagnosed with SB using BiteStrip® and randomly allocated to one of the following groups: with ND placement or without ND placement (intervention or control group, respectively). The mobility of the RPD abutment tooth was measured using Periotest® at baseline (T0) and at 1 (T1), 3 (T3), and 6 months (T6). BiteStrip® scores were recorded at T0 and T6. Intragroup comparisons of the Periotest® value (PTV) were performed using analysis of covariance. Intergroup comparisons of PTV and BiteStrip® scores were performed using the linear mixed model and Wilcoxon signed-rank test, respectively. Intragroup comparisons of BiteStrip® scores were performed using the Mann-Whitney U test.

RESULTS

At T6, the PTV in the intervention group was significantly lower than that in the control group (p=0.004). PTV was significantly lower at T6 than that at T0 in the intervention group (p=0.030), while PTV was significantly higher at T6 than that at T0 in the control group (p=0.007). There was no significant difference in the BiteStrip® score between the two groups. The BiteStrip® score at T6 was significantly lower than that at T0 only in the intervention group (p=0.011).

CONCLUSION

ND placement might inhibit the increase in mobility of RPD abutment teeth and be effective in protecting them in RPD wearers with SB.

Association of probable bruxism with periodontal status: A cross-sectional study in patients seeking periodontal care

OBJECTIVE

The goals of this study were to investigate the prevalence of probable bruxism in a group of patients seeking a periodontal care and the association between probable bruxism and periodontal status.

BACKGROUND

The results of previous studies evaluating the relationship between bruxism and periodontitis are contradictory. In addition, the relationship between probable bruxism and periodontitis in adults has not been evaluated, yet. Therefore, new studies are required in this field to clarify the relationship between bruxism and periodontitis.

METHODS

Patients seeking periodontal care at a university periodontology unit were considered in this study. Their periodontal diagnosis, number of missing teeth, presence of probable bruxism, and sociodemographic characteristics were recorded. The periodontal status of each study participant was defined according to the latest consensus of the American Association of Periodontology/European Federation of Periodontology, and the 2018 consensus report on the assessment of bruxism was used to evaluate probable bruxism. A multiple logistic regression analysis was performed to determine the effects of bruxism on periodontitis.

RESULTS

A total of 541 patients (289 females and 252 males, mean age 42.1 ± 15.9 years) were enrolled in the present study. The prevalence of probable bruxism was 36.6%. Additionally, 40.9% of the study population was diagnosed with periodontitis. The probable bruxers were older (P < 0.001), had a higher number of missing teeth (P < 0.001), and had poor periodontal status (P < 0.001). The multivariate logistic regression analysis suggested that probable bruxism was associated with periodontitis, after adjusting relevant factors (odds ratio: 2.243, 95% CI: 1.465-3.434, P < 0.001).

CONCLUSIONS

It was observed that the prevalence of probable bruxism was 36.6% and probable bruxers showed higher odds of periodontitis. Future studies with prospective randomized design should be conducted to confirm these results among a larger study population.

The prevalence of awake bruxism and sleep bruxism in the Dutch adult population

Background

Awake bruxism and sleep bruxism are common conditions amongst adult populations, although prevalence data are scarce.

Objective

This study aimed to assess the prevalence of awake bruxism and sleep bruxism in the Dutch adult population.

Methods

As part of a large epidemiologic survey on oral health of the general Dutch adult population, a total of 1209 subjects were asked about their bruxism behaviour during the day and during their sleep. The collected data were subjected to stratified analysis by five age groups (25‐34, 35‐44, 45‐54, 55‐64 and 65‐74 years), socioeconomic status, and gender.

Results

A prevalence of 5.0% of the total population was found for awake bruxism and of 16.5% for sleep bruxism. Regarding the five age groups, prevalence of 6.5%, 7.8%, 4.0%, 3.2% and 3.0%, respectively, were found for awake bruxism, and of 20.0%, 21.0%, 16.5%, 14.5% and 8.3%, respectively, for sleep bruxism. Women reported both awake bruxism and sleep bruxism more often than men. These differences were statistically significant. Concerning socioeconomic status (SES), both awake bruxism and sleep bruxism were more often found in high SES groups, being statistically significant for awake bruxism only.

Conclusion

Sleep bruxism is a common condition in the Dutch adult population, while awake bruxism is rarer.

In vivo prediction of temporomandibular joint disc thickness and position changes for different jaw positions

Temporomandibular joint disorders (TMD) are common dysfunctions of the masticatory region and are often linked to dislocation or changes of the temporomandibular joint (TMJ) disc. Magnetic resonance imaging (MRI) is the gold standard for TMJ imaging but standard clinical sequences do not deliver a sufficient resolution and contrast for the creation of detailed meshes of the TMJ disc. Additionally, bony structures cannot be captured appropriately using standard MRI sequences due to their low signal intensity. The objective of this study was to enable researchers to create high resolution representations of all structures of the TMJ and consequently investigate morphological as well as positional changes of the masticatory system. To create meshes of the bony structures, a single computed tomography (CT) scan was acquired. In addition, a high-resolution MRI sequence was produced, which is used to collect the thickness and position change of the disc for various static postures using bite blocks. Changes in thickness of the TMJ disc as well as disc translation were measured. The newly developed workflow successfully allows researchers to create high resolution models of all structures of the TMJ for various static positions, enabling the investigation of TMJ disc translation and deformation. Discs were thinnest in the lateral part and moved mainly anteriorly and slightly medially. The procedure offers the most comprehensive picture of disc positioning and thickness changes reported to date. The presented data can be used for the development of a biomechanical computer model of TMJ anatomy and to investigate dynamic and static loads on the components of the system, which could be useful for the prediction of TMD onset.

Prevalence of pain in the orofacial regions in patients visiting general dentists in the Northwest Practice-based REsearch Collaborative in Evidence-based DENTistry research network

BACKGROUND

This study aimed to measure prevalence of pain in the orofacial regions and determine association with demographics, treatment history, and oral health conditions in dental patients visiting clinics in the Northwest Practice-based REsearch Collaborative in Evidence-based DENTistry (PRECEDENT) research network.

METHODS

Data were recorded in a survey with systematic random sampling of patients (n = 1,668, 18 to 93 years old, 56% female) visiting 100 general dentists in the Northwest PRECEDENT research network. Prevalence ratios (PR) of orofacial pain by each variable were estimated by generalized estimating equations for Poisson regression.

RESULTS

The prevalence of orofacial pain during the past year was 16.1% (95% confidence interval [CI], 13.4-18.9), of which the most prevalent pain locations were dentoalveolar (9.1%; 95% CI, 7.0-11.2) and musculoligamentous tissues (6.6%; 95% CI, 4.5-8.7). Other locations included soft tissues (0.5%; 95% CI, 0.2-0.8) and nonspecific areas (0.6%; 95% CI, 0.2-1.0). The prevalence of dentoalveolar but not musculoligamentous pain decreased with age. When comparing the 18- to 29-year-old patients, dentoalveolar pain decreased significantly in 45- to 64-year-old patients (PR, 0.59; 95% CI, 0.4-0.9) and in those 65 years or older (PR, 0.5; 95% CI, 0.3-0.9). Sex significantly affected the prevalence of musculoligamentous but not dentoalveolar pain. Women (PR, 3.2; 95% CI, 2.0-5.1) were more likely to have musculoligamentous pain. The prevalence of dentoalveolar and musculoligamentous pain did not vary significantly by ethnicity. Dentoalveolar pain was reported more frequently in patients who did not receive dental maintenance (PR, 2.9; 95% CI, 2.1-4.2) and those visiting community-based public health clinics (PR, 2.2; 95% CI, 1.2-3.7).

CONCLUSIONS

One in 6 patients visiting a general dentist had experienced orofacial pain during the past year. Dentoalveolar and musculoligamentous pains were the most prevalent types of pain.

PRACTICAL IMPLICATIONS

Pain in the muscles and temporomandibular joints was reported as frequently as that in the teeth and surrounding tissues in patients visiting general dentists. Although the dental curriculum is concentrated on the diagnosis and management of pain and related conditions from teeth and surrounding tissues, it is imperative to include the training for other types of orofacial pain, particularly those from temporomandibular joint and musculoligamentous tissues.

Prevalence of temporomandibular dysfunction in children and adolescents

OBJECTIVE:

To review the prevalence of temporomandibular disorders (TMD) in children and adolescents, verifying the methodological variations.

DATA SOURCES:

Research conducted in Medline, PubMed, Lilacs and BBO databases, including manuscripts (except reviews and case reports) published from 1990 to 2012. The descriptors were "temporomandibular joint syndrome", "temporomandibular joint dysfunction syndrome", "temporomandibular joint disorders", "prevalence studies", and "cross-sectional studies"; the words "dysfunction", "disorder", "temporomandibular", "children", "adolescents", "prevalence", "frequency", and "transversal" were used.

DATA SYNTHESIS:

Seventeen articles were selected, and the TMD frequency varied from 16 to 68%. Regarding the methodological criteria, only three articles (18%) reported sample size determination, three (18%) clearly described the sample selection process by stratified selection technique, and nine studies (53%) carried out the calibration of the examiners. The diagnostic criteria used in the studies were: Helkimo index (n=2; 12%), Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) (n=4; 24%), the jaw index (n=1; 6%), clinical protocols (n=10; 59%), and anamnestic questionnaires (n=6; 35%).

CONCLUSIONS:

The TMD prevalence in children and adolescents varies in the literature. Appropriate and standardized methods are needed to identify, with greater validity, the presence of TMD in this population, allowing a better understanding of the pathological aspects in order to address more effective preventive and therapeutic procedures.

Prevalence of signs and symptoms indicative of temporomandibular disorders and headaches in 35-, 50-, 65- and 75-year-olds living in Västerbotten, Sweden

OBJECTIVE

The aim of this study was to analyze and compare prevalence of signs and frequently occurring symptoms indicative of temporomandibular disorder (TMD) and headaches in 35-, 50-, 65- and 75-year-old men and women in Västerbotten County, Sweden.

MATERIALS AND METHODS

From a total target population of 11 324 subjects living in Västerbotten County in the year 2002, 300 individuals in each age group were randomly selected. Of these, 998 (82% response rate) answered and returned a postal questionnaire and 779 (65% response rate) individuals accepted a clinical examination.

RESULTS

The prevalence of frequent TMD symptoms peaked among 50-year-old women and then declined. Women at this age reported significantly higher prevalence compared to men for all TMD symptoms except temporomandibular joint locking. In the 65- and 75-year-olds, the prevalence was practically equal between men and women as well as between these ages. Frequent headaches showed the highest prevalence among 35- and 50-year-old women, with a statistically significant difference between men and women of 50 years of age (p < 0.05). Fifty-year-old women had statistically significantly higher prevalence of muscle pain to palpation (p < 0.001), temporomandibular joint sounds (p < 0.01) and impaired maximal jaw opening capacity (p < 0.01), compared to 50-year-old men.

CONCLUSIONS

The different symptoms indicative of TMD and headaches showed a similar pattern, with higher prevalence among the 35- and 50-year-old, as compared to the 65- and 75-year-old, participants. The pattern may be related to biological, psychosocial or generation-related factors.

Review of aetiological concepts of temporomandibular pain disorders: towards a biopsychosocial model for integration of physical disorder factors with psychological and psychosocial illness impact factors

Several studies have reported that musculoskeletal disorders of the stomatognathic system, commonly known as temporomandibular disorders (TMD) resemble musculoskeletal disorders and chronic pain disorders in general. There is also general consensus that combined biomedical and biopsychosocial methods best support the assessment and management of the cardinal features of TMD, i.e., pain and dysfunction or physical (peripheral) and psychosocial (central) factors. This overview of the aetiology of TMD will outline conceptualizations of past models and present the current view that patients with TMD should be assessed according to both the physical disorder and the psychosocial illness impact factors. The conceptual theories outlined in this review include biomedical models related to temporomandibular joints, muscles of mastication and occlusal factors, psychological models and the biopsychosocial models. An integrated and multidimensional approach concerning physical and psychosocial factors in temporomandibular pain and dysfunction is presented as an example of how the biopsychosocial model and information processing theory may apply in the conceptualization and management of TMD for various health care professionals.

Invisalign(®) treatment of patients with craniomandibular disorders

The temporomandibular joint is one of the most complex joint systems in the human body. Craniomandibular disorders (CMD) are a common condition in which symptoms and signs may vary within a single individual and from one person to another. As anatomic and functional aspects of the craniomandibular system (CMS) and the upper cervical spine are closely interconnected, CMD need a close interdisciplinary approach combining orthopedics, manual medicine, orthodontics and dentistry. Splints as a therapeutic treatment instrument in CMD patients are widely accepted. The association of splint therapy and the Invisalign(®) system not only provides comfortable and almost invisible treatment but also constitutes a powerful instrument for the orthodontic treatment of the CMD patient. To this end, precise knowledge of the temporomandibular joint, temporomandibular disorders and treatment using removable and fixed splints is indispensable.

Patients seeking treatment for craniofacial pain: a retrospective study of 300 patients

Those engaged in any type of pain practice will encounter patients who have seen many practitioners. This is especially true for clinicians who treat craniofacial pain and temporomandibular disorders. In this retrospective study of 300 patients seeking treatment for various types of craniofacial pain, the average age was 43.05 years. A mean average of 3.92 clinicians was consulted with the range of practitioners being one to 26. The average time of pain was 4.15 years. Most of the subjects (210) were in the age groups 21 years to 60 years old. Females comprised 85.30% of the subjects with a mean average age of 43.43 years; 14.70% were male with a mean average age of 41.02 years.

Sexual dimorphism and temporomandibular disorders (TMD)

Numerous studies suggest a sexual predilection for temporomandibular disorders. The purpose of this article is to review and summarize patient-oriented and basic science studies that address the topic of a female predilection for temporomandibular disorders. The information presented provides oral and maxillofacial surgery practitioners with evidence-based data to suggest a female predilection for temporomandibular disorders based on biologic, genetic, and behavioral/psychosocial factors.

A follow-up study of subjective symptoms of temporomandibular disorders in patients who received acupuncture and/or interocclusal appliance therapy 18-20 years earlier

OBJECTIVE

To evaluate the presence of symptoms of temporomandibular disorders (TMDs) in patients referred to a specialist clinic because of muscular problems 18-20 years earlier and who had received mainly acupuncture and/or interocclusal appliance therapy.

MATERIAL AND METHODS

Sixty-five subjects who had received therapy at a TMD specialist clinic 18-20 years earlier were mailed a questionnaire with questions about TMD symptoms, their attitude towards the therapy, and their opinion about the outcome. Fifty-five subjects (85%) answered and returned the questionnaire.

RESULTS

Before therapy, 87% had had severe TMD symptoms, but this figure decreased to 38% at the long-term follow-up. The mean values of the subjects' complaints at worst and at best before treatment, measured with a visual analog scale, were 66 (range 26-100) and 31 (range 0-100), respectively. The corresponding figures at the long-term follow-up were 32 (range 0-96) and 16 (range 0-70). Headache at least once a week was originally reported by 73% of the women and by 77% of the men. Headache prevalence 18-20 years later was 35% in women and 54% in men. The majority of patients were positive about the therapy they had received, and would recommend it to a friend with similar complaints.

CONCLUSIONS

A majority of the patients reported a lasting improvement in their symptoms. Patients' overall opinions of the therapy received were positive.

The comparison between pains, difficulties in function, and associating factors of patients in subtypes of temporomandibular disorders

The aim of this study was to compare the multidimensional properties among subtypes of painful temporomandibular disorders (TMD): myofascial pain (group I), disc displacement (group II), arthralgia (group IIIa) and osteoarthritis (group IIIb). A total of 511 patients answered a battery of questionnaires, which included questions relating to intensity and duration of pain, the Japanese version of the McGill Pain Questionnaire, limitation of daily functions, the Hospital Anxiety and Depression Scale, the Eysenck Personality Questionnaire short-form and 34 items of behavioural contributing factors. Group IIIb showed significantly the highest age in all subtypes. Those in group I had higher depression scores than those in group II (P = 0.005). Group IIIa had a lower women's ratio than in group II (P = 0.001) and the patients showed a shorter pain duration than those in groups I (P = 0.000) and II (P = 0.001). Group IIIa patients also showed lower visual analogue scale (VAS) ratings for pain descriptors 'heavy' (P = 0.002) and 'tiring' (P = 0.004) than those of group I, and 'dull' (P = 0.005), 'heavy' (P = 0.001) and 'tiring' (P = 0.005) than those of group II. Group IIIa showed lower ratios of contributing factors of 'an awareness of grinding/clenching during sleep' (P = 0.000) and 'an awareness of clenching sensation when waking up at night' (P = 0.002) than those of group I, and also showed a higher ratio of 'a liking for a hard food' (P = 0.000) and lower ratio of 'talking for a long time on the telephone' (P = 0.001) than those of group II. In conclusion, although several properties were different between subtypes, the majority of them were similar in the four subtypes of TMD.

A prospective investigation over two decades on signs and symptoms of temporomandibular disorders and associated variables. A final summary

The aim of this summary of a longitudinal investigation on temporomandibular disorders (TMD) was to present the prevalence figures of signs and symptoms of TMD and certain other examined variables, and the correlations between these variables, over a 20-year period. Originally, 402 randomly selected 7-, 11-, and 15-year-olds were examined clinically and by means of a questionnaire. The same examination procedure was repeated three times: after 4-5 years and after 10 and 20 years, respectively. Signs and symptoms of TMD were mainly mild, but common already in childhood. They increased up to young adulthood, after which they leveled out. Progression to severe pain and dysfunction was rare, and spontaneous recovery from more pronounced symptoms was also rare. Significant correlations between reported bruxism and TMD symptoms were found, and a baseline report of tooth-grinding was a predictor of TMD treatment during the 20 years covered by the investigation. Occlusal factors were only weakly associated with TMD signs and symptoms. However, a lateral forced bite between the retruded contact position (RCP) and the intercuspal contact position (ICP) and a unilateral crossbite deserve further consideration as possible local risk factors for development of TMD. In conclusion, a substantial fluctuation of TMD signs and symptoms was observed in this sample of Swedish subjects followed for 20 years from childhood to adult. The demand for TMD treatment was low at all examinations, while the estimated treatment need was larger. One-third of subjects who had some kind of orthodontic treatment did not run a higher risk of developing TMD later in life.

Influence on the masticatory system in treatment of obstructive sleep apnea and snoring with a mandibular protruding device: A 2-year follow-up

The aim was to identify the incidence and types of possible adverse events in the masticatory system after treatment with a mandibular protruding device (MPD) during a 2-year period in patients with obstructive sleep apnea (OSA) or snoring. The subjects comprised 65 middle-aged patients (44 OSA patients, 21 snorers). A clinical examination and a questionnaire concerning signs and symptoms from the masticatory system were performed before, after 6 months, and after 2 years of MPD use. The frequencies of registered signs from the masticatory system, such as muscle and joint tenderness, palpation, and pain during mandibular movement, decreased significantly between baseline and the 2-year follow-up. There were significant changes in the mandibular range of protrusion (+0.7 mm, P < .001), overjet (-0.5 mm, P < .001), and overbite (-0.6 mm, P < .001) compared with the initial examination. Nine patients developed a lateral open bite during treatment, and 2 of them experienced subjective symptoms related to the altered occlusion but still used the MPD every night. No patient reported pain on opening the mouth wide or during jaw movements. Two reported tiredness on jaw function. The reported frequency of headaches was also significantly reduced (P < .01). The high compliance rate in MPD use showed that the therapy is well tolerated, but there is a risk of minor alterations in the occlusion during MPD treatment.

The association between psychological factors and oro-facial pain: a community-based study

OBJECTIVE

To examine the hypothesis that psychological factors of psychological distress, maladaptive response to illness and perception of happiness in childhood, are associated with self-reported oro-facial pain (OFP).

METHOD

A cross-sectional population-based study was conducted in South-East Cheshire, UK. The adjusted participation rate was 74%, and 2504 adults aged 18-65 years participated in the study.

RESULTS

A report of not having had a happy childhood was associated with risk of 1.6 (95% CI 1.4-2.0) of reporting OFP. An increased propensity to report symptoms associated with OFP was seen for those individuals with higher levels of psychological distress measured using the general health questionnaire (GHQ) with the risk of 2.7 (95% CI 2.3-3.2) in the highest category. All components of the illness behaviour questionnaire (IBQ) were associated with presence of OFP. There was a linear increase in risk (test for trend, P<0.01) associated with the report of OFP for general hypochondriasis, disease conviction, affective inhibition, affective disturbance, and irritability. However there was a significant decrease in risk with a high score for perception of illness (0.6; 95% CI 0.6-0.7) and denial (0.6; 95% CI 0.5-0.7). None of the factors showed significant change in estimates when adjusted for age and gender.

CONCLUSIONS

This large cross-sectional community-based study showed significant association for all of the factors considered. The obtained data raise interesting questions of cause and effect for which further, longitudinal studies are required to establish temporal relationship between these factors and the onset, cause, and treatment of OFP.

Orofacial pain: just another chronic pain? Results from a population-based survey

Features of somatisation have been shown to predict the onset of widespread body pain. This study aims to determine to what extent persons with orofacial pain syndromes share these features and to what extent they are uniquely related to oral mechanical factors. We have conducted a population-based cross-sectional survey in the South-East Cheshire area of the United Kingdom involving 2504 individuals aged 18-65 years. All participants completed a postal questionnaire which enquired about the occurrence of both orofacial pain and widespread body pain. It also enquired about potential risk factors for one or both conditions. In total, 473 subjects (23%) reported orofacial pain only, 123 (6%) widespread pain only, while 85 (4%) reported both. The number reporting both was significantly higher than would be expected if the symptoms were independent (P<0.001). Several oral mechanical factors were significantly associated with both orofacial pain and widespread body pain (grinding teeth, clicking jaw, missing teeth), while two (facial trauma, locking jaw) were specifically related to orofacial pain. Both pain syndromes were associated equally with high levels of psychological distress, indicators of somatisation and maladaptive response to illness. These results suggest that orofacial pain syndromes may commonly be a manifestation of the process of somatisation and the excess reporting of some local mechanical factors amongst persons with these symptoms, may not be uniquely associated with pain in the orofacial region.

Temporomandibular disorders in 19-year-old Korean men

PURPOSE

The purpose of this study was to determine the prevalence and the nature of the relationships between 3 temporomandibular joint disease (TMD) symptoms and symptoms of associated structures.

MATERIALS AND METHODS

This study was designed to rule out the effect from the uneven composition of the samples on TMD symptoms. The samples were collected from subjects who were of the same age, gender, district, and race. Nineteen-year old men (n = 27,978) were selected and investigated by means of questionnaires and clinical examinations. The prevalence of each symptom was studied and tried to determine the effects of the TMD-associated signs on the TMD signs. The indices allocated to reflect the TMD signs and symptoms and the others were dichotomized for bivariate analysis. The predictor variables were headache, neck pain, referred pain, stress, past trauma history in the TMJ, past TMJ dislocation, bruxism, and clenching. The outcome variables were mouth opening limitation, TMJ pain on rest, and TMJ pain during function.

RESULTS

The incidence of masticatory muscle stiffness was 17.8%; TMJ sounds, 14.3%; headache, 7.2%; neck pain, 13.5%; bruxism, 8.4%; and clenching, 9.9%. Stress occurred in 12.8%, past trauma history in 11%, and previous joint dislocation in 2.5%. The experience of dislocation in the TMJ was found to be the most important risk factor in terms of mouth opening limitation (odds ratio, 4.08, P <.0001), joint pain during function (odds ratio, 5.50, P <.0001), and joint pain in the rest state (odds ratio, 4.63, P <.0001). Referred pain and the experience of trauma in TMJ were the secondary risk factors in terms of joint pain and referred pain and the stress in terms of mouth opening limitation. Considering referred pain can be induced by TMD, stress may be more related to mouth opening limitation (odds ratio, 2.18, P <.0001), and the experience of trauma in TMJ may be more related to pain in the rest state (odds ratio, 2.56, P <.0001) and during function (odds ratio, 2.47, P <.0001).

CONCLUSIONS

The prevalence of TMD signs and symptoms as determined by this examination was in accord with the findings in women or mixed samples of other workers. Prior experience of a dislocated disc was found to be the most risky factor in TMD. Stress was related to limitations of mouth opening, and the experience of trauma in the TMJ was found to be related to pain in the joint region. Bruxism may not be a direct risk factor in TMD, and the clenching habit found to be more harmful than bruxism.

Oro-facial pain in the community: prevalence and associated impact

STUDY OBJECTIVE

To determine the prevalence of oro-facial pain (OFP) in the population and within-population subgroups and to describe the associated disability.

DESIGN

Cross-sectional population study.

SETTING

General medical practice in South East Cheshire, United Kingdom.

PARTICIPANTS

A random sample of 4000 adults aged 18-65 years of whom 2504 responded (adjusted participation rate 74%).

MAIN RESULTS

The overall prevalence of OFP was 26% (95% Confidence Interval (CI) 24%, 28%). The prevalence of symptoms was higher in women (30%) than in men (21%) and in both sexes the highest (30%) prevalence was found in the 18-25 year age group and the lowest (22%) in the 56-65 age group. Of all the participants, 12% had pain in or around the eyes, 10% reported pain in and around the temples, 6% pain in front of the ears and 6% pain in the jaw joints. Only 46% of the participants with OFP had sought professional advice from a dentist or general medical practitioner and 17% had to take time off work or were unable to carry out normal activities because of pain.

CONCLUSIONS

OFP is a common symptom experienced by a quarter of the adult population, of whom only 46% seek treatment. The prevalence is higher in women and younger age groups.

Treatment received, treatment demand, and treatment need for temporomandibular disorders in 35-year-old subjects

An epidemiological sample of 114 subjects was followed longitudinally from the age of 15 to 35 years with regard to treatment received, treatment demand, and treatment need for temporomandibular disorders (TMD). Some kind of TMD treatment had been provided to 18% of the subjects during the 20-year follow-up period. Eighty-five percent of those who had received previous TMD treatment reported that the treatment had had a positive effect on their symptoms. The estimated present need for treatment was 11%, but, in line with several other investigations, the active demand for such treatment was much less (3%). From age 15 to 25 years, a small but gradual increase of clinical signs of dysfunction was found. From the age of 25 to 35 years, however, a significant reduction of such signs was noted. One explanation for this reduction of clinical signs and symptoms of TMD might be the stomatognathic treatment received. It was concluded that 18% of the subjects had received some TMD treatment during the 20-year follow-up period. Only 3% still had a demand for such treatment at age 35.

The effect of altering jaw position on the transmission of vibration between the skull and teeth in humans

The forces that develop in the human temporomandibular joint during function have never been directly measured, yet many patients exhibit excessive localized wear and tear of the joint, suggesting that at times these forces exceed tissue tolerance. The purpose here was to gain insight into vibration transmission between the cranium and mandible in healthy humans during variations of jaw position. In 13 normal healthy adult men (age 25-40 years) with normal dentitions, vibration (around 400 Hz, sine wave) was applied to the skull vertex and changes in the intensity of the vibration signal were measured using several small linear accelerometers cemented to the buccal surfaces of mandibular first molars and the labial surfaces of maxillary central incisors. The jaw was opened, protruded and moved laterally by the individual participant and vibration signal intensities were tested (lower first molar signal/upper incisor signal) for change at each mandibular position by ANOVA. The results showed the vibration signal changed significantly with opening and less so on protrusion and laterotrusion. The vibration signal during opening could be categorized into three types: (1) signal increased continuously with increased opening; (2) signal increased, then reached a plateau during last third of opening; (3) signal increased, then decreased when the individual moved from 40 mm to maximum opening. These findings show that as the jaw moves laterally, and especially as it opens, the magnitude of the vibration signal increases substantially compared with the near-closed position.

The trend and risk factors of perceived toothache among Finnish adolescents from 1977 to 1997

Toothache is a subjective oral health indicator that should become uncommon when oral health is improving. The aim of this study was to assess changes in perceived toothache between 1977 and 1997 among Finnish adolescents. In the Adolescent Health and Lifestyle Survey, a self-administered questionnaire was mailed to a representative sample of 12-, 14-, 16-, and 18-year-old Finns every second year. The sample sizes in the surveys varied from 2422 to 11,105, making a total of 35,349 subjects in the entire study. The incidence of toothache during the previous 2 years was requested in 1977, 1985, 1991, 1995, and 1997, and the prevalences were 31%, 25%, 28%, 29%, and 37%, respectively. The increase between 1995 and 1997 was highest among 16- and 18-year-olds. There was no tendency for perceived toothache to decline over the study period, despite the decrease in caries experience. Toothache varied by age, socioeconomic status (SES), place of residence, and toothbrushing frequency. The increase in the incidence of toothache reported after 1995 could be a warning signal that economic recession in Finland has caused changes in the dental care system.

Systematic review of population-based epidemiological studies of oro-facial pain

OBJECTIVES

To conduct a systematic review of epidemiological literature in order to determine the prevalence and associated risk factors of oro-facial pain.

DATA

Population based observational studies (cohorts, cross-sectional and case-control studies) of oro-facial pain, published in the English language, prior to 1999 were included.

SOURCES

Electronic databases (Medline, Embase, Cinahl, BIDS and Health CD) were searched. Reference lists of relevant articles were examined, and the journals "Pain" and "Community Dentistry and Oral Epidemiology" were handsearched for the years 1994-1998.

RESULTS

The results of the search strategy were screened for relevance. A standardised checklist was used to assess the methodological quality of each study by two reviewers before an attempt was made to summarise the results. The median quality score was 70% of the maximum attainable score. Due to methodological issues, it was not possible to pool the data on the prevalence of oro-facial pain. Age, gender and psychological factors were found to be associated with OFP, however there was not enough information on other factors such as local mechanical and co-morbidities to draw any reliable conclusions. None of the factors fully fulfilled criteria for causality.

CONCLUSIONS

There is a need for good quality epidemiological studies of oro-facial pain in the general population. To enable comprehensive examination of the aetiology of oro-facial pain, it is necessary to address a broad range of factors including demography and life-style, local mechanical factors, medical history and psychological factors. Future studies should recruit adequately sized samples for precise determination of the prevalence and detection of important associated factors. Data on potential confounders and effect modifiers should also be collected and adjusted for in the statistical analysis.

Orofacial pain symptoms: an interaction between age and sex

This study investigated sex and age cohort differences in the subjective report of orofacial pain symptoms in a stratified sample of community dwelling adults. The subjects were 724 participants in the Florida Dental Care Study, a longitudinal study of oral health among dentate adults, age 45 and older at baseline. Pain prevalence and subjective ratings were assessed for a range of orofacial pain sites using a standardized telephone interview. The results suggest that the 6-month prevalence of jaw joint pain (8.3%), face pain (3.1%), toothache pain (12.0%), painful oral sores (15.6%), and burning mouth (1.6%) found in the FDCS sample are similar to United States population estimates. In addition, prevalence for pain when chewing and temperature sensitivity were also reported as 23% and 24% respectively, suggesting that these two seldom documented painful experiences are common. Female respondents reported higher 6-month prevalence for multiple symptoms and painful oral sores, with trends also observed for female sex as a risk factor for jaw joint pain and face pain, whereas males were more likely to report temperature sensitivity. A higher percentage of females rated their pain as severe enough to impact behavior for jaw joint pain, toothache pain, and painful oral sores. Few overall age effects were found, with the exception of higher prevalence of temperature sensitivity and pain when chewing in the 45--64-year-old group, compared to respondents in the 65+ age cohort. However, the most interesting finding was that when sex by age cohort comparisons were made, with the exception of painful oral sores, all significant differences in pain ratings were found within the 45--64-year-old cohort and not the 65+ group. This finding clarified inconsistencies found in earlier studies in the orofacial pain literature where sex differences in pain ratings were found in several adult samples of a wide range of ages but not in a sample of older adults.

The relationship between headache and symptoms of temporomandibular disorder in the general population

OBJECTIVES

To describe the relationship between headache and symptoms of temporomandibular disorder (TMD) in a general population, and to assess whether there are specific symptoms associated with headache.

METHODS

A personal interview survey conducted in 1995 on 483 adult subjects from the metropolitan community of Segrate, northern Italy.

RESULTS

The overall prevalence of headache in the past year was 21.2%. The prevalence of temporomandibular symptoms was 54.3%. Headache occurred significantly more in females than males (26.5 vs 15.4%), and in subjects with, rather than without, symptoms of TMD (27.4 vs 15.2%). Among symptoms, temporomandibular pain, temporomandibular joint sounds, and pain on movements of the jaw were associated with headache using a univariate analysis. After adjustment for confounding variables, a multiple logistic regression confirmed a significant relationship of headache with temporomandibular pain (OR 1.83, 95% CI, 1.07-3.15).

CONCLUSIONS

In the general adult population there is an association between headache and symptoms of TMD. A functional evaluation of the stomatognathic system should be therefore considered in subjects with unexplained headache, even if chronic conditions and mechanical symptoms of temporomandibular disorder are absent.

Clinical implications of sex in acute temporomandibular disorders

BACKGROUND

Previous research on temporomandibular disorders, or TMDs, has been somewhat limited, with studies having low numbers of subjects, restricting the focus to women or looking at patients already diagnosed with chronic TMD. Because early intervention is beneficial, it is important to understand the symptoms that men and women have in the acute stage of TMD.

METHODS

A total of 233 patients (161 women, 72 men) with acute TMD symptoms were assessed with a battery of biopsychosocial measures. Patients were diagnosed as having TMD on the basis of research diagnostic criteria, or RDC, or RDC, for TMD. After six months, patients were reassessed to determine whether they continued to have pain, thus classifying them as having chronic TMD. The authors found that 153 patients (47 men, 106 women) had developed a chronic condition, while 80 patients (25 men, 55 women) no longer reported pain (nonchronic).

RESULTS

Female and male patients who developed chronic TMD differed significantly from patients who had acute symptoms that subsided. Women who developed chronic TMD exhibited significantly more psychosocial distress and impairment than women who did not develop chronic TMD, in terms of Diagnostic and Statistical Manual, Fourth Edition, or DSM-IV, diagnoses; Beck Depression Inventory, or BDI, scores; Minnesota Multiphasic Personality Inventory scores; Multidimensional Pain Inventory, or MPI, scores; and physical and psychological measures assessed with the RDC for TMD. Men who developed chronic TMD differed significantly from men who did not develop chronic TMD, in that they exhibited more impairment in terms of DSM-IV diagnoses and BDI and RDC measures.

CONCLUSIONS

These findings provide evidence that significant differences exist between men and women in regard to acute TMD symptoms.

CLINICAL IMPLICATIONS

The biopsychosocial differences between men and women suggest that some treatments may be more beneficial for women than for men.

Relationship between systemic joint laxity, TMJ hypertranslation, and intra-articular disorders

The aim of this study was to evaluate the correlation between general joint hypermobility, temporomandibular joint (TMJ) hypertranslation and signs and symptoms of TMJ intra-articular disorders. One hundred twenty individuals constituted the sample, divided into two groups: Group I (symptomatic) included 60 patients with complaints of joint noises, pain, or jaw locking, and Group II (nonsymptomatic) included 60 people with no TMD complaints. The Beighton's hypermobility score addressed the systemic laxity while lateral x-rays taken in both closed and full open mouth positions measured TMJ mobility (condyle hypertranslation). No association was found between intra-articular disorders and systemic hypermobility (p > 0.05). A significant negative correlation (p < 0.05) was found between age and systemic hypermobility, while no correlation was detected between systemic and TMJ hypermobility (condyle hypertranslation).

Self-reported symptoms of temporomandibular dysfunction in a female university student population in Saudi Arabia

The symptoms of temporomandibular dysfunction (TMD), reported by 705 female university students of Riyadh, Saudi Arabia, are analysed. The population is representative of the educated class of Saudi Arabia. The most frequently reported symptoms were jaw feeling tired (34.5%), awareness of uncomfortable bite (31.3%), pain in front of the ear (22.4%) and discomfort upon wide opening (22.4%). The frequency of subjective reactions was, pain interferes with activity (42%), disturbed sleep (40.6%), taking of medication (27.8%) and pain being frustrating or depressing (26.8%). Some interesting relationships were found between the reported symptoms and marital status, residence and college of education. These findings are similar to those reported in a Bedouin community in Egypt, but lower than that in a Saudi Arabian population attending dental clinics, Saudi male dental students and high school students.

The effect of age and gender on the onset of symptomatic temporomandibular joint disk displacement

OBJECTIVE

The aim of this study was to test the hypotheses that incidence of symptomatic temporomandibular joint disk displacement is evenly distributed over all ages and between genders and that there is no gender difference in pain perception.

STUDY DESIGN

The study population consisted of 248 consecutive patients with radiographically verified symptomatic temporomandibular joint disk displacement. The time of onset of the condition relative to age and gender was determined, as was pain level.

RESULTS

There was a statistically significant peak in incidence of symptomatic temporomandibular joint disk displacement during adolescence for both genders. Teenage girls were found to run a risk of developing disk displacement that is three times greater than the risk for teenage boys, and girls were found to run a risk during puberty that is four times greater than their risk later in life. The age at onset of the condition did not differ between genders. Both female and male subjects reported the same degree of pain level.

CONCLUSION

The results point to a teenage preponderance and a sexual dimorphism with respect to incidence of symptomatic temporomandibular joint disk displacement.

Liaison psychiatry and psychology in dentistry

Dentists are trained to provide treatment for patients with straightforward problems that respond to routine therapy and do not recur. However, patients may present to dentists and complain solely of physical symptoms such as toothache, headache, and facial pain: only after much inappropriate treatment these symptoms are revealed to be due to emotional disturbance. The dentist may spend hours investigating such patients, in some of whom dental pathology may be present, but the symptoms and ensuing disability cannot be satisfactorily explained as a result. There are other patients who are preoccupied by physical symptoms or by their appearance. In others, anxiety may manifest itself as a phobia, or a dysmorphic concern about certain aspects of their appearance. This article reviews the role of liaison psychiatry and psychology in dentistry.

The functional status of the masticatory system of 11-16-year-old adolescents: classification and validity

Epidemiological studies to assess the prevalence and course of functional disturbances of the masticatory system should be based on a valid and reliable measure of the functional status of the masticatory system. NIELSEN et al. (2, 3) proposed a classification method that included three different classes of dysfunction. This classification was used to compare the results of a sample of 447 11-16-year-old Swiss adolescents with those of the Danish study and to test the validity of this classification method. The two studies showed similar prevalences in two of the three dysfunction classes and a similar pattern of dysfunction categories. Concurrent and construct validity analyses showed significant correlations between the assessment from clinical examination and the subjective judgments of the adolescents. The results demonstrated cross- and concurrent validation of the "Nielsen index" but also stressed the necessity of a careful re-evaluation of the "severe" class criterion. The limitations of the Nielsen index led to the construction of a "Zurich-MAP index". The potential applications of both indices are discussed.