Sleep and Orofacial Pain

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.

Measuring hair cortisol concentration, insomnia symptoms and quality of life in preschool children with severe early childhood caries - a case-control pilot study

OBJECTIVE

This study aimed to 1) investigate the relationships between hair cortisol concentration (HCC), insomnia symptoms, Health-Related Quality of Life (HRQoL) and Oral Health-Related Quality of Life (OHRQoL) in preschool children with severe early childhood caries, 2) compare HCC, insomnia symptoms, HRQoL and OHRQoL in preschool children with severe early childhood caries with these factors in children without clinical signs of dental caries, and 3) explore correlations between caries scores and HCC, insomnia symptoms, HRQoL and OHRQoL.

MATERIAL AND METHODS

A case-control pilot study, including 12 children with severe early childhood caries and 28 controls, aged 3-5 years. Dental examination was performed and hair samples for cortisol were taken. Parents filled out questionnaires about their child's insomnia symptoms, HRQoL and OHRQoL. Interpreters were used in families with language difficulties.

RESULTS

The key findings in this pilot study were tendencies that children with severe early childhood caries had more insomnia symptoms, and poorer OHRQoL than the controls. Caries scores was correlated with insomnia symptoms and OHRQoL.

CONCLUSIONS

Dentists should include questions about the child's sleep when they see the child, as insomnia related to dental caries may lead to several physical, mental, and social problems.

Involvement of Oxidative Stress and Nutrition in the Anatomy of Orofacial Pain

Pain is a very important problem of our existence, and the attempt to understand it is one the oldest challenges in the history of medicine. In this review, we summarize what has been known about pain, its pathophysiology, and neuronal transmission. We focus on orofacial pain and its classification and features, knowing that is sometimes purely subjective and not well defined. We consider the physiology of orofacial pain, evaluating the findings on the main neurotransmitters; in particular, we describe the roles of glutamate as approximately 30-80% of total peripheric neurons associated with the trigeminal ganglia are glutamatergic. Moreover, we describe the important role of oxidative stress and its association with inflammation in the etiogenesis and modulation of pain in orofacial regions. We also explore the warning and protective function of orofacial pain and the possible action of antioxidant molecules, such as melatonin, and the potential influence of nutrition and diet on its pathophysiology. Hopefully, this will provide a solid background for future studies that would allow better treatment of noxious stimuli and for opening new avenues in the management of pain.

Temporomandibular Disorders Within the Context of Sleep Disorders

This paper provided an overview of the knowledge on the relationship between temporomandibular disorders (TMDs) and the main sleep conditions and disorders of dental interest, namely, sleep bruxism (SB), sleep apnea, and gastroesophageal reflux disease (GERD). It emerged that although the topic of SB as a possible detrimental factor for the stomatognathic structures has been the most studied, evidence is growing that SB, obstructive sleep apnea, and GERD, all belong to a circle of mutually interacting sleep disorders and conditions that, in turn, may be associated with TMDs. The pathophysiology of the cause-and-effect relationships, if existing, has to be elucidated yet.

The impact of the COVID-19 pandemic on orofacial pain practice: Perceptions from a convenience sample of orofacial pain practitioners

BACKGROUND

COVID-19 has had a substantial impact on people's lives. Increasing evidence indicates that patients with chronic pain particularly are being affected; however, few articles have examined how the pandemic has affected the care or clinical presentation of patients with orofacial pain. The aim of this study was to describe COVID-19-related changes in referral patterns and numbers, in patient demographics, in patients' seeking treatment for problems, and in administrative procedures in 3 orofacial pain clinical settings.

METHODS

Practitioners participating in the American Academy of Orofacial Pain webinar titled "Practicing Orofacial Pain, Headache, and Sleep Care During the COVID-19 Pandemic" completed a voluntary anonymous online survey. Survey respondents completed general questions related to their orofacial pain practices and about perceptions of their patients' symptoms. For statistical analysis, the authors calculated frequencies and used analysis of variance for continuous variables or Likert scale variables and the χ² test for dichotomous or categorical variables. Statistical significance was set at P value of .05 or below.

RESULTS

Practitioners noted an increase in new patients with orofacial pain. Of the participants, 33% indicated the onset of their patients' pain was often or extremely often related to COVID-19. The 5 most common symptoms that providers felt were aggravated in their patients were masticatory muscle myalgia, anxiety, tension-type headache, bruxism, and insomnia or fragmented sleep.

CONCLUSION

The COVID-19 pandemic has resulted in a marked increase in the number of patients seeking consultation for orofacial pain and associated symptoms.

PRACTICAL IMPLICATIONS

Because of the COVID-19 pandemic, orofacial pain practitioners have noticed an increase in orofacial pain symptoms across practice settings.

Masticatory Myofascial Pain Disorders

Masticatory myofascial pain disorders (MMPD) are a common group of orofacial pain conditions affecting the muscles of mastication, with headache and cervical disorders as well as chronic widespread pain and psychosocial disorders being common comorbid conditions. As their pathophysiology is multifactorial in nature, a multimodal and interdisciplinary approach should be considered. Overall treatment goals include decreasing pain and disability, increasing mandibular range of motion, and improving quality of life. This article describes a complex case exhibiting common characteristics of MMPD while additionally reviewing the literature on classification, pathophysiology, and evidence-based treatment planning.

Qualitative Impressions of a Yoga Nidra Practice for Insomnia: An Exploratory Mixed-Methods Design

Introduction: Insomnia affects up to half of the U.S. population, and due to limitations of current treatments, there is a growing interest in mind-body practices to reduce insomnia. To understand how a guided meditation practice, Yoga Nidra, may affect relaxation and align with current descriptions of nonpharmaceutical practices that could improve sleep, qualitative and quantitative methods were used to explore participant experience of a single Yoga Nidra practice, administered in a group setting. Methods: Current insomnia (Insomnia Severity Index), sleep practices, and mood (positive and negative affect schedule [PANAS]) were measured at intake. After 30 min of Yoga Nidra practice, the PANAS was readministered. In a focus group that followed, participants discussed their experience before, during, and after the practice and the likelihood of repeating it. Six groups were conducted. All interested adults were welcome to join. Results: In the final sample of 33 individuals (79% female), 80% of participants reported insomnia at intake and 45% reported a regular mind-body practice, supporting the prevalence of insomnia in the society as well as the interest in mind-body practices. After the Yoga Nidra intervention, mean negative affect decreased 5.6 ± 4.5 points, a 31% decrease from baseline, and positive affect decreased 3.5 ± 9.7 points, a 13% decrease. Three major themes were identified from focus group discussions: response to the practice (relaxation, perceived sleep, and sense withdrawal); factors that affect engagement (delivery method and intrapersonal factors); and potential as a clinical intervention (for conditions including sleep, anxiety, and pain). Conclusion: Yoga Nidra appeared tolerable within the sample, and descriptions suggest it may be useful for enhancing relaxation, facilitating sleep, easing anxiety, and reducing pain. Results from this study will inform the design of future studies of Yoga Nidra for insomnia and related conditions.

Disturbed sleep may be a core risk factor for jaw functional limitation in patients with painful temporomandibular disorders

BACKGROUND

Pain related to temporomandibular disorder (TMD) usually affects jaw function. In patients with TMD, little is known about the biopsychosocial relevance to jaw functional limitations.

OBJECTIVE

This study explored the impact of biopsychosocial risk factors on jaw functional limitation in patients with painful TMD.

METHODS

A comprehensive set of patient-reported outcomes (PROs), consisting of pain severity (Brief Pain Inventory), psychological stress (Symptom Checklist-90-Revised), catastrophising thought (Pain Catastrophizing Scale), kinesiophobia (Tampa Scale for Kinesiophobia-TMD), sleep quality (Pittsburgh Sleep Quality Index) and jaw functional limitation (Jaw Functional Limitation Scale-20), were administered, and clinical examinations were performed in patients with TMD.

RESULTS

This study included the data obtained from 131 patients with painful TMD. In the logistic regression analysis, biomedical factors (age, sex, pain duration and TMD phenotype) were not associated with jaw functional limitation. Correlations were higher in the order of sleep quality (ρ = 0.946), pain severity (ρ = 0.582), pain catastrophising (ρ = 0.535), kinesiophobia (ρ = 0.486) and emotional distress (ρ = 0.268). Multiple regression analysis demonstrated three predictors, including pain severity (p = .001), kinesiophobia (p = .023) and sleep quality (p < .001) for jaw functional limitation. In the mediation analysis, the indirect effect of pain severity on the association between sleep and limitation was significant (p < .0001).

CONCLUSION

Jaw functional limitation is associated with biopsychosocial factors. In particular, sleep may be a core risk factor for functional limitation in patients with painful TMD.

Review of Literatures: Physiology of Orofacial Pain in Dentistry

The objective of this review of the literature is to summarize the physiology of orofacial pain in dentistry, particularly physiology of the pain pathway and molecular mechanisms on pathophysiology of pain, on account of new insights into classification of orofacial pain related diseases. This article will also focus on possible mechanisms of neuropathic orofacial pain which is distinguished from other types of pain.