ORAL HABITS OF TEMPOROMANDIBULAR DISORDER PATIENTS WITH MALOCCLUSION

Evaluation of the effect of unilateral mastication on the morphology of temporomandibular joint from the perspective of dynamic joint space

BACKGROUND

Unbalanced alterations of temporomandibular joint morphology were associated with unilaterally masticatory habits.

OBJECTIVE

This study aimed to investigate the effect of unilateral mastication on the remodelling of the temporomandibular joint using dynamic joint space.

METHODS

Twelve volunteers with non-maxillofacial deformity and healthy temporomandibular joints were recruited. The 3D models of the mandible and the maxilla were reconstructed according to computed tomography. The subjects were asked to masticate French fries and peanuts unilaterally, which was recorded by a 3D motion capture system. The dynamic joint space during unilateral mastication was analysed.

RESULTS

During early closure, the joint space reduction on the non-masticatory side was significantly greater than on the masticatory side (p < .05). During later closure, the joint space reduction on the non-masticatory side was significantly lower than that on the masticatory side (p < .05). The difference in joint space reduction between both sides was greater than the French fries while masticating the peanuts.

CONCLUSIONS

Unilateral mastication resulted in a different major pressure area on the bilateral TMJs. Therefore, unilateral mastication might be an essential factor in the bilateral asymmetrical remodelling of the TMJ.

Temporomandibular Disorders: Implications in Restorative Dentistry and Orthodontics

Over the past several decades, the science of restorative/reconstructive dentistry and orthodontics has evolved tremendously, following sound principles passed down from robust literature and scientific rationale. These principles have been solid and instrumental in enhancing dentistry, from a single tooth restoration to complex full-mouth rehabilitations. However, it must be noted that some of the principles and philosophies followed over these decades have been questioned based on the advances in science, technology, and evidence-based medicine. The scenario became complex when clinicians were faced with the question of guidance for optimum joint and muscle health as related to restorative dentistry and orthodontics.

Sleep and awake bruxism in adults and its relationship with temporomandibular disorders: A systematic review from 2003 to 2014

OBJECTIVE

In order to establish a relationship between bruxism and temporomandibular disorders (TMDs), a systematic review was performed.

MATERIALS AND METHODS

A systematic research was performed based on PubMed, Cochrane Library, Medline, Embase, BIREME, Lilacs and Scielo data bases, between 2003 and 2014 including all languages. Descriptive clinical cases were identified. Two independent authors selected the articles. PICO format was used to analyse the studies and the Newcastle-Ottawa Scale (NOS) was used to verify the quality of the evidence.

RESULTS

Thirty-nine studies (n = 39) were analysed in this review. According to bruxism diagnosis, articles were grouped as follows: polysomnographic diagnosis (PSG) (n = 7), clinical diagnosis (n = 11) and survey/self-report (n = 21). Thirty-three articles (n = 33) established a positive relation between bruxism and TMD and six (n = 6) did not. Quality of evidence was low to moderate. In general, the most part of the studies showed shortcomings on their design with bias risk, and also had a low sensitivity on bruxism diagnosis.

CONCLUSIONS

The evidence based on PSG was not as conclusive as the studies that used surveys and clinical exam to diagnosis bruxism, when bruxism was related to TMD. Sleep bruxism could be associated with myofascial pain, arthralgia and joint pathology as disc displacement and joint noises. Although the evidence at present is inconclusive and does not provide information according to the type of bruxism (bruxism sleep and wakefulness), it is possible to suggest that bruxism would be associated with TMD.

A survey on the potential relationships between TMD, possible sleep bruxism, unilateral chewing, and occlusal factors in Turkish university students

OBJECTIVE

To evaluate whether there is a relationship between possible sleep bruxism (PSB), temporomandibular disorders (TMD), unilateral chewing (UC), and occlusal factors in university students recruited from Cumhuriyet University in Turkey.

METHODS

For this cross-sectional survey, 519 (223 males, mean age 21.57 ± 2.3 years, 296 females, mean age 21.02 ± 2 years) university students who admitted to the Department of Oral and Maxillofacial Radiology of the Faculty of Dentistry, Cumhuriyet University for dental care between 2012 and 2014 were selected randomly. Students were asked to complete a questionnaire form including questions about TMD, PSB and UC. Presence and direction of malocclusion were recorded during clinical examination. Chi-square test was used for statistical analysis.

RESULTS

It was found that 96.6% of the students with PSB had TMD (p < 0.05). The prevalence of severe TMD was high among students with PSB. There was a significant association between UC, PSB and TMD (p < 0.05). No statistically significant association was found between occlusal factors and PSB and TMD (p > 0.05).

CONCLUSION

Sleep bruxism, which heavily depends on self-report, is significantly associated with TMD. Unilateral chewing seems to be a common factor for development of SB and TMD. However, further studies are needed to corroborate this finding. Additionally, this study supports the hypothesis that occlusal factors are not related to self-reported sleep bruxism.

Reported concepts for the treatment modalities and pain management of temporomandibular disorders

Background

Pain related to temporomandibular disorders (TMD) is a common problem in modern societies. The aim of the article is to present the concepts of TMD pain clinical management.

Methods

A survey was performed using the PubMed, SCOPUS and CINAHL databases for documents published between 1994 and 2014. The following search keywords were selected using MeSH terms of the National Library of Medicine in combination: TMD pain, TMD, TMJ, TMJ disorders, occlusal splint, TMD physiotherapy, TMJ rheumatoid disorders and TMJ surgery. Original articles and review papers which presented the clinical relevance and practical validity regarding the possibility of application in TMD management have been included. Authors have excluded articles without outstanding practical aspect and evidence-based background. A first selection was carried out by reviewing titles and abstracts of all articles found according to the criteria. After that the full texts of potentially suitable articles were assessed. In line with these criteria, among 11467 results the writers have included 66 papers.

Results

The most commonly reported conservative treatments are massage therapy and individually fabricated occlusal splints. In addition to massage, other popular methods include manual therapy and taping, warming/cooling of aching joints, and light and laser therapy. Drugs are also commonly used. In the most severe cases of the temporomandibular joint degeneration, surgical restoration of the joint is sometimes applied.

Conclusions

The authors concluded that conservative treatment including counselling, exercises, occlusal splint therapy, massage, manual therapy and others should be considered as a first choice therapy for TMD pain because of their low risk of side effects. In the case of severe acute pain or chronic pain resulting from serious disorders, inflammation and/or degeneration pharmacotherapy, minimally invasive and invasive procedures should be considered.

Evaluation of occlusal factors in patients with temporomandibular joint disorder

OBJECTIVE: The aim of this study was to determine the prevalence and the relation between the main occlusal factors and the temporomandibular disorder (TMD). METHODS: We analyzed 100 patients (50 diagnosed with TMD and 50 asymptomatic volunteers, control group) through a questionnaire that classified TMD as absent, mild, moderate and severe. Then, an evaluation was made of intraoral occlusal factors: Absence of posterior teeth, wear facets, overjet, overbite, open bite, posterior crossbite, sagittal relationship (Class I, II and III), centric relation discrepancy for maximum intercuspation, anterior guidance and balancing occlusal interference. The c² examined the association between TMD and considered occlusal variables. RESULTS: The prevalence of studied occlusal factors was higher in patients with moderate and severe TMD. Statistically significant results were found on: Absence of five or more posterior teeth, overbite and overjet greater than 5 mm, edge-to-edge bite, posterior crossbite, Class II and III, the absence of effective anterior guide and balancing side interferences. CONCLUSIONS: Indeed, it is concluded that there is a relationship between TMD and occlusal factors, however it can not be told to what extent these factors are predisposing, precipitating or perpetuating the disease. Therefore, despite its multifactorial etiology, one can not neglect the occlusal analysis of these patients.

Sensorimotor cortical activation in patients with sleep bruxism

Sleep bruxism is assumed to be triggered by a dysfunctional subcortical and cortical network. This study investigates sensorimotor cortical activation in patients with sleep bruxism during clenching and chewing. Nine polysomnographically diagnosed patients and nine healthy control subjects underwent magnetoencephalography (MEG). During clenching and chewing, patients with bruxism revealed significantly larger event-related desynchronization in the somatomotor area (Brodmann area 4) than healthy subjects. Group differences in the muscle activity were ruled out by electromyography (EMG) assessments during MEG. This result might be regarded as a consequence of increased sensorimotor cortical representation of the tongue and chewing musculature due to an enhanced parafunctional muscle activity in bruxers potentially triggered by occlusal factors. Alternatively, a secondary activation of cortical structures during sleep bruxism in the context of an activated network of subcortical and cortical structures might lead to increased cortical representation of the chewing musculature via use dependent plasticity.

Relação entre bruxismo, fatores oclusais e hábitos bucais

OBJETIVO: avaliar a relação entre bruxismo, fatores oclusais e hábitos bucais em crianças e adolescentes, alunos da rede pública da cidade de Brasília/DF. MÉTODOS: um grupo de 680 escolares, de ambos os gêneros, na faixa etária de 4 a 16 anos, foi aleatoriamente selecionado. Os dados foram coletados através da avaliação clínica e da aplicação de questionários aos responsáveis pelos alunos. Os aspectos morfológicos da oclusão foram avaliados segundo a classificação de Angle e critérios para a dentadura decídua, de Foster e Hamilton (1969). As mordidas cruzadas anterior e posterior, uni ou bilateral, foram avaliadas. O teste qui-quadrado, a Odds Ratio e o software SPSS foram utilizados para análise estatística. RESULTADOS E CONCLUSÕES: 592 questionários retornaram de maneira completa. A prevalência de bruxismo foi de 43%, enquanto 57% apresentaram má oclusão. Os hábitos bucais foram observados em 53%. A prevalência de má oclusão aumentou de 42,6% na dentadura decídua para 74,4% na dentadura permanente. A avaliação dos resultados indicou que não houve relação estatisticamente significativa entre o bruxismo e os fatores oclusais estudados (p > 0,05). Não foram encontradas diferenças entre os gêneros em ambas as variáveis. A onicofagia foi o hábito mais prevalente (35%) com preferência para o gênero feminino. Houve relação estatisticamente significativa entre bruxismo e hábitos bucais. Avaliando os tipos específicos de hábitos, apenas a sucção de chupeta se mostrou relacionada ao bruxismo. Estudos adicionais serão necessários para melhor compreensão dos fatores locais na gênese do bruxismo.