Temporomandibular Disorders Within the Context of Sleep Disorders

Snoring as a Possible Protective Factor for Temporomandibular Joint Disorders

BACKGROUND

Previous studies have linked sleep quality to temporomandibular joint disorders (TMD), suggesting a role for snoring in this association. However, the directionality of this relationship remains a subject of debate. This investigation aimed to elucidate the connections between snoring and TMD.

METHODS

This research employed a two-sample Mendelian randomization (MR) approach, leveraging publicly available large-scale genome-wide association study (GWAS) data on snoring and TMD. We utilised a suite of analytical methods, including the inverse variance weighted (IVW) method, maximum likelihood estimation, adjusted profile score, weighted median, MR-Egger regression, and a series of sensitivity analyses, to rigorously assess the existence of relationships.

RESULTS

Our findings indicate that a greater genetic predisposition to snoring is significantly associated with a reduced risk of TMD (IVW method; odds ratio [OR] = 0.156, 95% confidence interval [CI] = 0.028-0.843, p = 0.0309). Conversely, the analysis did not support a potential influence of TMD on snoring susceptibility (IVW method; 95% CI = 0.990 to 1.002, p = 0.1926). Additionally, our sensitivity analyses did not reveal any significant pleiotropy that could bias these findings.

CONCLUSION

This MR study provides limited but novel genetic evidence supporting a potential causal link between snoring and a decreased risk of developing TMD. On the other hand, it does not substantiate an effect of TMD on the likelihood of snoring.

Effectiveness of telerehabilitation-supported exercises in patients with temporomandibular disorders with probable sleep bruxism during the COVID-19 pandemic: A randomized controlled trial

OBJECTIVE

This study evaluated telerehabilitation-supported exercises' effects on pain, neck disability, anxiety, oral behaviors, and sleep quality in patients with Temporomandibular Disorders associated with probable sleep bruxism (TMDs-SB).

METHODS

During the COVID-19 pandemic (March 2021-May 2022), 40 patients aged 18-65 with TMDs-SB were randomized to a telerehabilitation (n = 20) or home exercise (n = 20) groups. Both received education and exercises; the telerehabilitation group supervised 30-minute weekly WhatsApp video sessions for eight weeks. Outcomes were assessed at baseline and eight weeks.

RESULTS

Both groups improved significantly in all outcomes from baseline to eight-week follow-up (p < .05). Telerehabilitation showed greater reductions in morning jaw pain (p = .012), neck disability (p = .032), trait anxiety (p = .028), and oral behaviors (p = .001) versus home exercises. Sleep quality improved similarly in both groups (p = .154).

CONCLUSIONS

Telerehabilitation effectively reduced TMDs-SB symptoms, offering a promising alternative to unsupervised exercises during the pandemic. Given this unique context, conducting studies outside the pandemic's conditions would enhance generalizability and clarify telerehabilitation's potential. Further studies are needed to confirm its efficacy beyond pandemic conditions.

Evaluating the association of temporomandibular disorders with audiological symptoms through instrumental diagnostics: A systematic review

OBJECTIVE

Temporomandibular disorders (TMDs) have been historically linked to symptoms such as tinnitus, hearing loss, and vertigo. The aim of this systematic review is to investigate the association between TMDs and audiological symptoms.

METHODS

Adhering to the PRISMA guidelines, a comprehensive literature search in three databases was performed searching for studies utilizing imaging and audiometric assessments to diagnose TMDs and audiological symptoms. Of the 1153 studies retrived, a total number of 6 studies were included.

RESULTS

Although tinnitus was commonly reported among patients with TMDs, objective audiological deficits were not consistently confirmed. The majority of existing studies lack standardized diagnostic methods and the heterogeneity of methodologies and limited sample sizes restricted the feasibility of a meta-analysis.

CONCLUSIONS

The lack of appropriate instrumental diagnostic tests makes it difficult to draw conclusions about the causal relationship between TMDs and audiological symptoms. Future trials are needed to clarify this clinical association.

Sleep Disorders Affecting Prognosis of Dental Treatment

This study provided an overview of the knowledge on the main sleep-related disorders and conditions affecting the prognosis of dental treatment: sleep bruxism (SB), obstructive sleep apnea (OSA), and gastroesophageal reflux disease (GERD). Current scientific evidence seems to suggest that these phenomena (ie, SB, OSA, GERD) belong to a circle of mutually relating sleep disorders and conditions where dental practitioners can play a key role in diagnosis and treatment.

The enigma of sleep: Implications of sleep neuroscience for the dental clinician and patient

BACKGROUND

Sleep disturbances have been shown to result in considerable morbidity and mortality. It is important for dental clinicians to understand the neuroscience behind sleep disorders.

TYPES OF STUDIES REVIEWED

The authors conducted a search of the literature published from January 1990 through March 2024 of sleep medicine-related articles, with a focus on neuroscience. The authors prioritized articles about the science of sleep as related to dental medicine.

RESULTS

The authors found a proliferation of articles related to sleep neuroscience along with its implications in dental medicine. The authors also found that the intricate neuroscientific principles of sleep medicine are being investigated robustly. The salient features of, and the differences between, central and obstructive sleep apneas have been elucidated. Sleep genes, such as CRY, PER1, PER2, and CLOCK, and their relationship to cancer and neurodegeneration are also additions to this rapidly developing science.

CONCLUSIONS AND PRACTICAL IMPLICATIONS

The dental clinician has the potential to be the first to screen patients for possible sleep disorders and make prompt referrals to the appropriate medical professionals. This can be lifesaving as well as minimize potential future morbidity for the patient.

Evaluation of the efficacy and quality of life in patients with temporomandibular joint disorders treated with Kovacs digital occlusal splint: a pilot study

BACKGROUND

Few studies have been conducted on treating temporomandibular disorders (TMDs) with new digital occlusal splints, which has increasingly attracted wide attention.

METHODS

To evaluate the clinical efficacy and quality of life (QoL) of Kovacs digital occlusal splint (KDOS) treatment in patients with TMD.

MATERIALS AND METHODS

Eighty-nine patients with TMD who were treated using KDOS were analyzed. The patients were divided into three groups according to the Wilkes stage. The clinical symptoms and QoL scores of the patients in each group were recorded before and at least three months after treatment, and the data were statistically analyzed and compared. The relationships between the disease severity, sex, age, and level of QoL before treatment and improvement in the clinical symptoms were analyzed using binary logistic regression.

RESULTS

The mean age and follow-up period of the patients were 28.0 ± 10.4 years and 4.9 ± 2.1 months, respectively. After KDOS treatment, the improvement rates of joint noise and pain were 80.4% and 69.8%, respectively. Additionally, the patients' maximum mouth opening and global QoL mean scores significantly improved compared to those before treatment (p < 0.001). Binary logistic regression analysis revealed that the factors affecting the improvement in the clinical symptoms were disease severity and level of QoL before treatment.

CONCLUSIONS

KDOS can improve the clinical symptoms and QoL of patients with TMD. Moreover, patients without osteoarthritis and with low pretreatment QoL levels are more likely to demonstrate clinical improvement.

TRIAL REGISTRATION

The trial was registered with Chinese Clinical Trial Registry (ChiCTR) (ID: ChiCTR2300076518) on 11/10/2023.

A mechanoluminescent material, ZnS:Mn,Li, with enhanced brightness for visualizing dental occlusion

Mechanoluminescent materials are characterized by high luminescence intensity, high repeatability, no external voltage activation, and a good linear relationship between stress and mechanoluminescence intensity within a certain range. Therefore, mechanoluminescent materials have attracted increasing attention from researchers in the fields of stress sensing, encryption and anti-counterfeiting, structural health monitoring, energy-saving lighting, intelligent wearable devices, and other fields. In this study, ZnS:Mn powders with different Mn2+ ratios and different ion doping were synthesized by a high-temperature solid-phase reaction, and the synthesis of various materials was characterized. Then, the optimal mechanoluminescence effect of the ZnS:1%Mn,1%Li material was obtained. The photoluminescence intensity of ZnS:1%Mn,1%Li was 16.7 times higher than that of the sample without doping with Li+, and the mechanoluminescence intensity was 1.64 times higher. Finally, polyethylene terephthalate (PET) film was combined with ZnS:Mn,Li mechanoluminescent powders to prepare flexible three-layer composite film. Based on this, a feasible strategy for the detection of temporomandibular disorders was proposed. The composite film is easy to use, economical, and safe, and has good mechanoluminescent performance, which has potential application value in the field of occlusal force detection and visualization.

Oral Health Implications of Obstructive Sleep Apnea: A Literature Review

BACKGROUND

Obstructive sleep apnea (OSA) is a prevalent sleep disorder characterized by repeated episodes of partial or complete obstruction of the upper airway during sleep. While the systemic implications of OSA are well documented, the dental consequences are less frequently discussed yet equally significant. This review aims to elucidate the oral health impacts of OSA, emphasizing the importance of interdisciplinary care.

METHODS

A comprehensive literature search was conducted across several databases to identify studies examining the relationship between OSA and various oral health parameters. The review included observational studies, clinical trials, and systematic reviews published in English up to January 2024.

RESULTS

OSA was significantly associated with heightened risks of bruxism, dry mouth, periodontal disease, temporomandibular joint disorders, palatal and dental changes, and alterations in taste sensation. Mouth breathing associated with OSA was a critical factor in exacerbating xerostomia and dental caries. Furthermore, the systemic inflammation induced by OSA appeared to correlate with the severity of periodontal disease. Patients using oral appliance therapy for OSA also showed notable changes in dental occlusion and required ongoing dental monitoring.

CONCLUSIONS

The findings underscore the bidirectional relationship between OSA and oral health, highlighting the need for dental professionals to be integral participants in the management of OSA. Early dental evaluation and intervention can contribute to the overall health and quality of life of individuals with OSA. The review advocates for the development of clinical guidelines to facilitate the early identification and management of OSA-related oral health issues within dental practice and encourages a collaborative approach to patient care.

Obstructive sleep apnoea, sleep bruxism and gastroesophageal reflux - mutually interacting conditions? A literature review

The purpose of the present manuscript is to provide an overview for researchers and clinicians summarizing the knowledge concerning the relationship between some of the main sleep-related conditions of dental interest: sleep bruxism (SB), obstructive sleep apnoea (OSA) and gastroesophageal reflux disease (GERD). Starting with the discussion of the evolving current knowledge on SB, the interconnections are discussed. Most of the available literature focused on the possible relationship between OSA and SB, but a clear pathophysiological connection or temporal relationship has not been identified. Despite the paucity of data on the possible commonalities, SB, OSA and GERD constitute a complex network of conditions that may affect the clinical and research dental practice, and they are rarely found in isolation. In this scenario, the key role of dental practitioners as sentinel in the case of these sleep-related conditions is important, thanks to their ability and the knowledge to identify signs, symptoms and risk factors that are signs of ongoing sleep-related conditions. Thus, dental practitioners are recommended to view bruxism as a potential gateway to medicine.

Inflammatory Markers and Sleep Architecture in Sleep Bruxism-A Case-Control Study

Background: Sleep bruxism (SB) is a common sleep-related movement behavior with a multifaceted etiology and a deficiently understood pathophysiology. A recent hypothesis suggests a link between SB and systemic inflammation. The scope of the study was to determine whether bruxers have altered sleep structure and different levels of inflammatory parameters compared to nonbruxers. Methods: A total of 83 adults underwent full-night polysomnography. The polysomnograms were evaluated using the American Academy of Sleep Medicine (AASM) guidelines. Then, the blood samples were obtained from the participants by venipuncture and the analyses were performed. The study group was divided based on bruxism episode index (BEI) into two groups: BEI ≤ 4 and BEI > 4. Results: In comparison with nonbruxers, the oxygen desaturation index (ODI) was significantly higher in severe bruxers (7.5 ± 11.08 vs. 3.33 ± 5.75, p < 0.005), as well as the arousal parameters (7.77 ± 4.68 vs. 4.03 ± 2.97, p < 0.001), and the mean oxygen desaturation (3.49 ± 0.69 vs. 3.01 ± 0.67, p < 0.05). Moreover, the differences in sleep architecture and deprivation of the deep sleep phase were observed, the non-REM sleep stage 3 was significantly shorter in severe bruxers (p < 0.03). Differences were also noted in non-REM sleep stage 1 and REM sleep phase. In the investigated group, there were no statistical differences in inflammatory cytokines levels between bruxers and nonbruxers. Conclusions: Sleep bruxism is associated with sleep structure alterations and may be associated with deep sleep phase deprivation. The inflammatory markers are not linearly correlated with the severity of sleep bruxism expressed as BEI.