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Uchima Koecklin KH, Aliaga-Del Castillo A, Li P. The neural substrates of bruxism: current knowledge and clinical implications. Front Neurol 2024; 15:1451183. [PMID: 39410996 PMCID: PMC11473305 DOI: 10.3389/fneur.2024.1451183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2024] [Accepted: 09/19/2024] [Indexed: 10/19/2024] Open
Abstract
Bruxism is a complex orofacial behavior that can occur during sleep or wakefulness, characterized by the involuntary grinding or clenching of teeth, involving repetitive activity of the jaw muscles. Its etiology is multifactorial, influenced by genetic, psychological, physiological, and lifestyle factors. While the mild bruxism may not necessitate treatment, severe bruxism can lead to significant consequences, including tooth damage, jaw pain, fatigue, and headaches. The bruxism has been associated with medical conditions, such as stress, anxiety, sleep disorders, and various neurological disorders; however, the exact pathophysiology remains elusive. Although the central nervous system is strongly implicated in the development of bruxism, specific neural substrates have not yet been conclusively established. Furthermore, there is evidence to suggest that individuals with bruxism may exhibit neural plasticity, resulting in the establishment of distinct neural circuitry that control the jaw movements. The application of various neurophysiological techniques in both clinical and pre-clinical studies provides valuable insights into the neural mechanisms underlying bruxism. This review aims to comprehensively examine the current literature on the neural pathways involved in bruxism, with the goal of improving the clinical approach and therapeutics for this condition. A deeper understanding of the neural circuitry controlling bruxism holds the potential to advance future treatment approaches and improve the management of patients with bruxism.
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Affiliation(s)
- Karin Harumi Uchima Koecklin
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, United States
- Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor, MI, United States
| | - Aron Aliaga-Del Castillo
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of Michigan, Ann Arbor, MI, United States
| | - Peng Li
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, United States
- Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor, MI, United States
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, United States
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Ricci A, Rubino E, Serra GP, Wallén-Mackenzie Å. Concerning neuromodulation as treatment of neurological and neuropsychiatric disorder: Insights gained from selective targeting of the subthalamic nucleus, para-subthalamic nucleus and zona incerta in rodents. Neuropharmacology 2024; 256:110003. [PMID: 38789078 DOI: 10.1016/j.neuropharm.2024.110003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 04/26/2024] [Accepted: 05/14/2024] [Indexed: 05/26/2024]
Abstract
Neuromodulation such as deep brain stimulation (DBS) is advancing as a clinical intervention in several neurological and neuropsychiatric disorders, including Parkinson's disease, dystonia, tremor, and obsessive-compulsive disorder (OCD) for which DBS is already applied to alleviate severely afflicted individuals of symptoms. Tourette syndrome and drug addiction are two additional disorders for which DBS is in trial or proposed as treatment. However, some major remaining obstacles prevent this intervention from reaching its full therapeutic potential. Side-effects have been reported, and not all DBS-treated individuals are relieved of their symptoms. One major target area for DBS electrodes is the subthalamic nucleus (STN) which plays important roles in motor, affective and associative functions, with impact on for example movement, motivation, impulsivity, compulsivity, as well as both reward and aversion. The multifunctionality of the STN is complex. Decoding the anatomical-functional organization of the STN could enhance strategic targeting in human patients. The STN is located in close proximity to zona incerta (ZI) and the para-subthalamic nucleus (pSTN). Together, the STN, pSTN and ZI form a highly heterogeneous and clinically important brain area. Rodent-based experimental studies, including opto- and chemogenetics as well as viral-genetic tract tracings, provide unique insight into complex neuronal circuitries and their impact on behavior with high spatial and temporal precision. This research field has advanced tremendously over the past few years. Here, we provide an inclusive review of current literature in the pre-clinical research fields centered around STN, pSTN and ZI in laboratory mice and rats; the three highly heterogeneous and enigmatic structures brought together in the context of relevance for treatment strategies. Specific emphasis is placed on methods of manipulation and behavioral impact.
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Affiliation(s)
- Alessia Ricci
- Uppsala University, Department of Organism Biology, 756 32 Uppsala, Sweden; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Eleonora Rubino
- Uppsala University, Department of Organism Biology, 756 32 Uppsala, Sweden; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Gian Pietro Serra
- Uppsala University, Department of Organism Biology, 756 32 Uppsala, Sweden; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Åsa Wallén-Mackenzie
- Uppsala University, Department of Organism Biology, 756 32 Uppsala, Sweden; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA.
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Pecori A, Luppieri V, Santin A, Spedicati B, Zampieri S, Cadenaro M, Girotto G, Concas MP. Clenching the Strings of Bruxism Etiopathogenesis: Association Analyses on Genetics and Environmental Risk Factors in a Deeply Characterized Italian Cohort. Biomedicines 2024; 12:304. [PMID: 38397906 PMCID: PMC10887134 DOI: 10.3390/biomedicines12020304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 01/24/2024] [Accepted: 01/25/2024] [Indexed: 02/25/2024] Open
Abstract
Bruxism is a worldwide oral health problem. Although there is a consensus about its multifactorial nature, its precise etiopathogenetic mechanisms are unclear. This study, taking advantage of a deeply characterized cohort of 769 individuals (aged 6-89 years) coming from Northern Italy's genetically isolated populations, aims to epidemiologically describe environmental risk factors for bruxism development and identify genes potentially involved through a Genome-Wide Association Study (GWAS) approach. Logistic mixed models adjusted for age and sex were performed to evaluate associations between bruxism and possible risk factors, e.g., anxiety, smoking, and alcohol and caffeine intake. A case-control GWAS (135 cases, 523 controls), adjusted for age, sex, and anxiety, was conducted to identify new candidate genes. The GTEx data analysis was performed to evaluate the identified gene expression in human body tissues. Statistical analyses determined anxiety as a bruxism risk factor (OR = 2.54; 95% CI: 1.20-5.38; p-value = 0.015), and GWAS highlighted three novel genes potentially associated with bruxism: NLGN1 (topSNP = rs2046718; p-value = 2.63 × 10-7), RIMBP2 (topSNP = rs571497947; p-value = 4.68 × 10-7), and LHFP (topSNP = rs2324342; p-value = 7.47 × 10-6). The GTEx data analysis showed their expression in brain tissues. Overall, this work provided a deeper understanding of bruxism etiopathogenesis with the long-term perspective of developing personalized therapeutic approaches for improving affected individuals' quality of life.
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Affiliation(s)
- Alessandro Pecori
- Institute for Maternal and Child Health—IRCCS “Burlo Garofolo”, Via dell’Istria 65, 34137 Trieste, Italy; (A.P.); (V.L.); (B.S.); (S.Z.); (M.C.); (G.G.); (M.P.C.)
| | - Valentina Luppieri
- Institute for Maternal and Child Health—IRCCS “Burlo Garofolo”, Via dell’Istria 65, 34137 Trieste, Italy; (A.P.); (V.L.); (B.S.); (S.Z.); (M.C.); (G.G.); (M.P.C.)
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Strada di Fiume, 447, 34149 Trieste, Italy
| | - Aurora Santin
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Strada di Fiume, 447, 34149 Trieste, Italy
| | - Beatrice Spedicati
- Institute for Maternal and Child Health—IRCCS “Burlo Garofolo”, Via dell’Istria 65, 34137 Trieste, Italy; (A.P.); (V.L.); (B.S.); (S.Z.); (M.C.); (G.G.); (M.P.C.)
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Strada di Fiume, 447, 34149 Trieste, Italy
| | - Stefania Zampieri
- Institute for Maternal and Child Health—IRCCS “Burlo Garofolo”, Via dell’Istria 65, 34137 Trieste, Italy; (A.P.); (V.L.); (B.S.); (S.Z.); (M.C.); (G.G.); (M.P.C.)
| | - Milena Cadenaro
- Institute for Maternal and Child Health—IRCCS “Burlo Garofolo”, Via dell’Istria 65, 34137 Trieste, Italy; (A.P.); (V.L.); (B.S.); (S.Z.); (M.C.); (G.G.); (M.P.C.)
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Strada di Fiume, 447, 34149 Trieste, Italy
| | - Giorgia Girotto
- Institute for Maternal and Child Health—IRCCS “Burlo Garofolo”, Via dell’Istria 65, 34137 Trieste, Italy; (A.P.); (V.L.); (B.S.); (S.Z.); (M.C.); (G.G.); (M.P.C.)
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Strada di Fiume, 447, 34149 Trieste, Italy
| | - Maria Pina Concas
- Institute for Maternal and Child Health—IRCCS “Burlo Garofolo”, Via dell’Istria 65, 34137 Trieste, Italy; (A.P.); (V.L.); (B.S.); (S.Z.); (M.C.); (G.G.); (M.P.C.)
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Shah T, Dunning JL, Contet C. At the heart of the interoception network: Influence of the parasubthalamic nucleus on autonomic functions and motivated behaviors. Neuropharmacology 2022; 204:108906. [PMID: 34856204 PMCID: PMC8688299 DOI: 10.1016/j.neuropharm.2021.108906] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 11/22/2021] [Accepted: 11/25/2021] [Indexed: 02/05/2023]
Abstract
The parasubthalamic nucleus (PSTN), a small nucleus located on the lateral edge of the posterior hypothalamus, has emerged in recent years as a highly interconnected node within the network of brain regions sensing and regulating autonomic function and homeostatic needs. Furthermore, the strong integration of the PSTN with extended amygdala circuits makes it ideally positioned to serve as an interface between interoception and emotions. While PSTN neurons are mostly glutamatergic, some of them also express neuropeptides that have been associated with stress-related affective and motivational dysfunction, including substance P, corticotropin-releasing factor, and pituitary adenylate-cyclase activating polypeptide. PSTN neurons respond to food ingestion and anorectic signals, as well as to arousing and distressing stimuli. Functional manipulation of defined pathways demonstrated that the PSTN serves as a central hub in multiple physiologically relevant networks and is notably implicated in appetite suppression, conditioned taste aversion, place avoidance, impulsive action, and fear-induced thermoregulation. We also discuss the putative role of the PSTN in interoceptive dysfunction and negative urgency. This review aims to synthesize the burgeoning preclinical literature dedicated to the PSTN and to stimulate interest in further investigating its influence on physiology and behavior.
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Affiliation(s)
- Tanvi Shah
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA
| | - Jeffery L Dunning
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA
| | - Candice Contet
- The Scripps Research Institute, Department of Molecular Medicine, La Jolla, CA, USA.
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After-effects of acute footshock stress on sleep states and rhythmic masticatory muscle activity during sleep in guinea pigs. Odontology 2022; 110:476-481. [PMID: 35000009 DOI: 10.1007/s10266-021-00679-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 12/01/2021] [Indexed: 10/19/2022]
Abstract
This study investigated the effects of acute footshock stress (FS) on the occurrence of rhythmic masticatory muscle activity (RMMA) during sleep in guinea pigs. Animals were prepared for chronic recordings from electroencephalogram, electrooculogram and electromyograms of neck and masseter muscles. The signals were recorded for six hours on the two successive days: the first day with stress-free condition (non-FS condition) and the second day with acute FS (FS condition). Sleep/wake states and RMMA were scored visually. Sleep variables and the frequency of RMMA occurring during non-rapid eye movement (NREM) sleep were compared during 6-h periods between the two conditions. Compared to non-FS condition, the amount of total sleep and NREM sleep significantly reduced during 2 h following the acute FS in the FS condition. Similarly, the frequency of RMMA significantly increased during 2 h following the acute FS for the FS condition compared to non-FS condition. During 2-6 h after FS in the FS condition, sleep variables and the frequency of RMMA did not differ from those without FS in the non-FS condition. These results suggest that acute experimental stress can induce transient changes in sleep-wake states and the occurrence of RMMA in experimental animals.
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Bhattacharjee B, Saneja R, Bhatnagar A, Gupta P. Effect of dopaminergic agonist group of drugs in treatment of sleep bruxism: A systematic review. J Prosthet Dent 2021; 127:709-715. [PMID: 33455727 DOI: 10.1016/j.prosdent.2020.11.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 11/17/2020] [Accepted: 11/17/2020] [Indexed: 01/02/2023]
Abstract
STATEMENT OF PROBLEM Various factors are responsible for sleep bruxism; however, whether the dopaminergic agonist group of drugs is effective in the treatment of sleep bruxism is unclear. PURPOSE The purpose of this systematic review was to evaluate the effect of the dopaminergic agonist group of drugs in controlling sleep bruxism in comparison with no treatment or placebo-controlled treatment. MATERIAL AND METHODS Two electronic databases, PubMed and Cochrane Central, were searched by using the keywords bruxism, sleep bruxism, dopamine, and dopamine agonist. After screening titles and abstracts, only those articles which met predefined inclusion criteria were selected for full-text assessment. Clinical trials using the dopaminergic agonist group of drugs as a treatment approach to sleep bruxism were included. RESULTS The literature search yielded a total of 64 articles from the 2 electronic databases (PubMed, 53; Cochrane Central, 11). After removal of the duplicates (n=8), the initial screening of titles and abstracts was performed by 2 independent reviewers, removing 46 articles. A total of 10 articles were selected for full-text reading, and 4 studies were included for qualitative analysis. CONCLUSIONS Levodopa (L-DOPA) and Bromocriptine showed decrease in root mean square value in electromyography per bruxism burst (P<.001) and 20% to 30% reduction of bruxism episodes during sleep in 2 different studies. However, treatment with bromocriptine led to conflicting result in another study in terms of frequency of bruxism episodes and amplitude of muscle contractions in electromyography (EMG). Bruxism bursts and episodes were also not significantly improved with another dopaminergic agonist group of drugs, Pramipexole (P>.001). Based on the limited evidence and conflicting results, significant conclusions cannot be generated, and further studies are required.
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Affiliation(s)
- Bappaditya Bhattacharjee
- Junior Resident, Department of Prosthodontics, Faculty of Dental sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India.
| | - Ritu Saneja
- Junior Resident, Department of Prosthodontics, Faculty of Dental sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Atul Bhatnagar
- Professor, Department of Prosthodontics, Faculty of Dental sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Pinki Gupta
- Junior Resident, Department of Prosthodontics, Faculty of Dental sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
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Garmroudinezhad Rostami E, Touchette É, Huynh N, Montplaisir J, Tremblay RE, Battaglia M, Boivin M. High separation anxiety trajectory in early childhood is a risk factor for sleep bruxism at age 7. Sleep 2020; 43:zsz317. [PMID: 31894243 PMCID: PMC7355392 DOI: 10.1093/sleep/zsz317] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 11/18/2019] [Indexed: 12/25/2022] Open
Abstract
STUDY OBJECTIVES The evolution of sleep bruxism manifestations and their co-occurrence with separation anxiety in early childhood remain unclear. Our threefold aim was to: (1) describe developmental sleep bruxism trajectories in early childhood, (2) investigate co-occurrences between trajectories of sleep bruxism and separation anxiety, and (3) determine whether distinct trajectories of separation anxiety increase the risk of presenting sleep bruxism during the first year of elementary school. METHODS This study is part of the Québec Longitudinal Study of Child Development. Sleep bruxism scores were assessed from age 1.5 to 7 years with the Self-Administered Questionnaire for Mother (n = 1946). Separation anxiety scores were measured from age 1.5 to 6 years with the Interviewer-Completed Computerized Questionnaire (n = 2045). RESULTS We identified four sleep bruxism trajectories from age 1.5 to 6 years: High-Increasing sleep bruxism at age 1.5 (14.1%), High-Increasing sleep bruxism at age 4 (18.3%), Low-Persistent sleep bruxism (12.1%), and Never-Persistent sleep bruxism (55.5%); and four separation anxiety trajectories from age 1.5 to 6 years: Low-Persistent separation anxiety (60.2%), High-Increasing separation anxiety (6.9%), High-Decreasing separation anxiety (10.8%), and Low-Increasing separation anxiety (22.1%). Sleep bruxism and separation anxiety trajectories were weakly associated (X2 = 37.84, p < 0.001). Compared with preschoolers belonging to the Low-Persistent separation anxiety trajectory, preschoolers in the High-Increasing separation anxiety trajectory had almost double the risk of presenting sleep bruxism at age 7 (95% CI = 1.25-3.22, p = 0.04). CONCLUSION When separation anxiety issues are detected in early childhood, it would be useful to target sleep bruxism during the first year of elementary school.
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Affiliation(s)
- Elham Garmroudinezhad Rostami
- Research Unit on Children’s Psychosocial Maladjustment, Québec, Québec, Canada
- School of Psychology, Laval University, Québec, Québec, Canada
| | - Évelyne Touchette
- Research Unit on Children’s Psychosocial Maladjustment, Québec, Québec, Canada
- Department of Psychoeducation, Université du Québec à Trois-Rivières, Trois-Rivières, Québec, Canada
| | - Nelly Huynh
- Faculty of Dental Medicine, University of Montréal, Montréal, Québec, Canada
- Research Centre, CHU Ste-Justine, Montreal, Québec, Canada
| | - Jacques Montplaisir
- Centre for Advanced Research in Sleep Medicine, Hôpital du Sacré-Coeur de Montréal, Montréal, Québec, Canada
- Departments of Pediatrics and Psychology, University of Montréal, Montréal, Québec, Canada
| | - Richard E Tremblay
- Research Unit on Children’s Psychosocial Maladjustment, Québec, Québec, Canada
- Research Centre, CHU Ste-Justine, Montreal, Québec, Canada
- Departments of Pediatrics and Psychology, University of Montréal, Montréal, Québec, Canada
- Geary Institute for Public Policy, UCD School of Economics and School of Public Health, Physiotherapy and Sports Science, University College Dublin, Dublin, Ireland
| | - Marco Battaglia
- Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
- Division of Child, Youth, & Emerging Adulthood Psychiatry, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Michel Boivin
- Research Unit on Children’s Psychosocial Maladjustment, Québec, Québec, Canada
- School of Psychology, Laval University, Québec, Québec, Canada
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Steuer I, Guertin PA. Central pattern generators in the brainstem and spinal cord: an overview of basic principles, similarities and differences. Rev Neurosci 2019; 30:107-164. [PMID: 30543520 DOI: 10.1515/revneuro-2017-0102] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 03/30/2018] [Indexed: 12/11/2022]
Abstract
Central pattern generators (CPGs) are generally defined as networks of neurons capable of enabling the production of central commands, specifically controlling stereotyped, rhythmic motor behaviors. Several CPGs localized in brainstem and spinal cord areas have been shown to underlie the expression of complex behaviors such as deglutition, mastication, respiration, defecation, micturition, ejaculation, and locomotion. Their pivotal roles have clearly been demonstrated although their organization and cellular properties remain incompletely characterized. In recent years, insightful findings about CPGs have been made mainly because (1) several complementary animal models were developed; (2) these models enabled a wide variety of techniques to be used and, hence, a plethora of characteristics to be discovered; and (3) organizations, functions, and cell properties across all models and species studied thus far were generally found to be well-preserved phylogenetically. This article aims at providing an overview for non-experts of the most important findings made on CPGs in in vivo animal models, in vitro preparations from invertebrate and vertebrate species as well as in primates. Data about CPG functions, adaptation, organization, and cellular properties will be summarized with a special attention paid to the network for locomotion given its advanced level of characterization compared with some of the other CPGs. Similarities and differences between these networks will also be highlighted.
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Affiliation(s)
- Inge Steuer
- Neuroscience Unit, Laval University Medical Center (CHUL - CHU de Québec), 2705 Laurier Blvd, Quebec City, Quebec G1V 4G2, Canada
| | - Pierre A Guertin
- Neuroscience Unit, Laval University Medical Center (CHUL - CHU de Québec), 2705 Laurier Blvd, Quebec City, Quebec G1V 4G2, Canada
- Faculty of Medicine, Department of Psychiatry and Neurosciences, Laval University, Quebec City, Quebec G1V 0A6, Canada
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Chen JM, Yan Y. Long-term follow-up of a patient with venlafaxine-induced diurnal bruxism treated with an occlusal splint: A case report. World J Clin Cases 2019; 7:516-524. [PMID: 30842964 PMCID: PMC6397809 DOI: 10.12998/wjcc.v7.i4.516] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 01/08/2019] [Accepted: 01/26/2019] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Bruxism is a jaw-muscle activity characterized by the clenching or grinding of teeth. It can be divided into nocturnal bruxism and diurnal bruxism (DB). DB secondary to antidepressants is rare and refractory. Reports associated with antidepressant-induced DB are mostly anecdotal without long-term follow-up. The effect of drug intervention on antidepressant-induced DB is still contested. We herein report the first case of successful treatment of venlafaxine-induced DB with an occlusal splint.
CASE SUMMARY This case report describes detailed 7-year follow-up of a patient with venlafaxine-induced DB treated with an occlusal splint. The patient who complained about involuntary daytime tooth grinding after taking venlafaxine for a period of 4 mo and was diagnosed with venlafaxine-induced DB. Subsequently, an occlusal splint with modified bilateral buccal-pterygoid pads was used to treat his tooth grinding and to protect the dental structures from tooth wearing. The patient reported remission of symptoms after several months of treatment. His grinding activity was gradually and stably controlled after 2 years, with an almost complete recovery from DB after 6 years.
CONCLUSION The maxillary buccal-pterygoid splint can be used as a noninvasive approach to treat venlafaxine-induced DB.
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Affiliation(s)
- Jia-Min Chen
- Department of Prosthodontics, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055, Guangdong Province, China
| | - Ying Yan
- Department of Prosthodontics, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055, Guangdong Province, China
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Martynowicz H, Dymczyk P, Dominiak M, Kazubowska K, Skomro R, Poreba R, Gac P, Wojakowska A, Mazur G, Wieckiewicz M. Evaluation of Intensity of Sleep Bruxism in Arterial Hypertension. J Clin Med 2018; 7:jcm7100327. [PMID: 30301160 PMCID: PMC6210463 DOI: 10.3390/jcm7100327] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 09/28/2018] [Accepted: 10/03/2018] [Indexed: 01/22/2023] Open
Abstract
Sleep bruxism (SB) is a masticatory muscle activity during sleep that is characterized as rhythmic (phasic) or non-rhythmic (tonic). The recent hypothesis on the etiology of SB supports the role of the central and autonomic nervous systems. Therefore, in this study, we aimed to assess the intensity of SB in patients with arterial hypertension. A total of 70 adults participated in this study: 35 patients with hypertension (study group) and 35 normotensive subjects (control group). Data were recorded using home portable cardiorespiratory polygraphy. The bruxism episode index (BEI) in the study group was found to be significantly higher compared to the control group (3.4 ± 3.25 vs. 2.35 ± 2.29, p = 0.04). Hypertension, higher body mass index (BMI), lower values of mean oxygen saturation (SpO2), and a higher percentage of SpO2 < 90% constituted independent risk factors for increased BEI. These results suggest the need for special oral care in hypertensive patients, patients with higher BMI, lower values of SpO2 and a higher percentage of SpO2 < 90%.
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Affiliation(s)
- Helena Martynowicz
- Department of Internal Medicine, Occupational Diseases, Hypertension and Clinical Oncology, Wroclaw Medical University, 213 Borowska St., 50-556 Wroclaw, Poland.
| | - Pawel Dymczyk
- Department of Internal Medicine, Occupational Diseases, Hypertension and Clinical Oncology, Wroclaw Medical University, 213 Borowska St., 50-556 Wroclaw, Poland.
| | - Marzena Dominiak
- Department of Oral Surgery, Wroclaw Medical University, 26 Krakowska St., 50-425 Wroclaw, Poland.
| | - Klaudia Kazubowska
- Department of Oral Surgery, Wroclaw Medical University, 26 Krakowska St., 50-425 Wroclaw, Poland.
| | - Robert Skomro
- Division of Respiratory, Critical Care and Sleep Medicine, University of Saskatchewan, 107 Wiggins Road, SK S7N 5E5 Saskatoon, Saskatchewan, Canada.
| | - Rafal Poreba
- Department of Internal Medicine, Occupational Diseases, Hypertension and Clinical Oncology, Wroclaw Medical University, 213 Borowska St., 50-556 Wroclaw, Poland.
| | - Paweł Gac
- Department of Hygiene, Wroclaw Medical University, 7 Mikulicza-Radeckiego St., 50-345 Wroclaw, Poland.
| | - Anna Wojakowska
- Department of Internal Medicine, Occupational Diseases, Hypertension and Clinical Oncology, Wroclaw Medical University, 213 Borowska St., 50-556 Wroclaw, Poland.
| | - Grzegorz Mazur
- Department of Internal Medicine, Occupational Diseases, Hypertension and Clinical Oncology, Wroclaw Medical University, 213 Borowska St., 50-556 Wroclaw, Poland.
| | - Mieszko Wieckiewicz
- Department of Experimental Dentistry, Wroclaw Medical University, 26 Krakowska St., 50-425 Wroclaw, Poland.
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Evaluation of the impact of the cancer therapy everolimus on the central nervous system in mice. PLoS One 2014; 9:e113533. [PMID: 25436776 PMCID: PMC4250083 DOI: 10.1371/journal.pone.0113533] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 10/24/2014] [Indexed: 01/13/2023] Open
Abstract
Cancer and treatments may induce cognitive impairments in cancer patients, and the causal link between chemotherapy and cognitive dysfunctions was recently validated in animal models. New cancer targeted therapies have become widely used, and their impact on brain functions and quality of life needs to be explored. We evaluated the impact of everolimus, an anticancer agent targeting the mTOR pathway, on cognitive functions, cerebral metabolism, and hippocampal cell proliferation/vascular density in mice. Adult mice received everolimus daily for 2 weeks, and behavioral tests were performed from 1 week after the last treatment. Everolimus-treated mice displayed a marked reduction in weight gain from the last day of the treatment period. Ex vivo analysis showed altered cytochrome oxidase activity in selective cerebral regions involved in energy balance, food intake, reward, learning and memory modulation, sleep/wake cycle regulation, and arousal. Like chemotherapy, everolimus did not alter emotional reactivity, learning and memory performances, but in contrast to chemotherapy, did not affect behavioral flexibility or reactivity to novelty. In vivo hippocampal neural cell proliferation and vascular density were also unchanged after everolimus treatments. In conclusion, two weeks daily everolimus treatment at the clinical dose did not evoke alteration of cognitive performances evaluated in hippocampal- and prefrontal cortex-dependent tasks that would persist at one to four weeks after the end of the treatment completion. However, acute everolimus treatment caused selective CO modifications without altering the mTOR effector P70S6 kinase in cerebral regions involved in feeding behavior and/or the sleep/wake cycle, at least in part under control of the solitary nucleus and the parasubthalamic region of the hypothalamus. Thus, this area may represent a key target for everolimus-mediating peripheral modifications, which has been previously associated with symptoms such as weight loss and fatigue.
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12
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Schmitt O, Eipert P, Kettlitz R, Leßmann F, Wree A. The connectome of the basal ganglia. Brain Struct Funct 2014; 221:753-814. [PMID: 25432770 DOI: 10.1007/s00429-014-0936-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Accepted: 10/30/2014] [Indexed: 01/22/2023]
Abstract
The basal ganglia of the laboratory rat consist of a few core regions that are specifically interconnected by efferents and afferents of the central nervous system. In nearly 800 reports of tract-tracing investigations the connectivity of the basal ganglia is documented. The readout of connectivity data and the collation of all the connections of these reports in a database allows to generate a connectome. The collation, curation and analysis of such a huge amount of connectivity data is a great challenge and has not been performed before (Bohland et al. PloS One 4:e7200, 2009) in large connectomics projects based on meta-analysis of tract-tracing studies. Here, the basal ganglia connectome of the rat has been generated and analyzed using the consistent cross-platform and generic framework neuroVIISAS. Several advances of this connectome meta-study have been made: the collation of laterality data, the network-analysis of connectivity strengths and the assignment of regions to a hierarchically organized terminology. The basal ganglia connectome offers differences in contralateral connectivity of motoric regions in contrast to other regions. A modularity analysis of the weighted and directed connectome produced a specific grouping of regions. This result indicates a correlation of structural and functional subsystems. As a new finding, significant reciprocal connections of specific network motifs in this connectome were detected. All three principal basal ganglia pathways (direct, indirect, hyperdirect) could be determined in the connectome. By identifying these pathways it was found that there exist many further equivalent pathways possessing the same length and mean connectivity weight as the principal pathways. Based on the connectome data it is unknown why an excitation pattern may prefer principal rather than other equivalent pathways. In addition to these new findings the local graph-theoretical features of regions of the connectome have been determined. By performing graph theoretical analyses it turns out that beside the caudate putamen further regions like the mesencephalic reticular formation, amygdaloid complex and ventral tegmental area are important nodes in the basal ganglia connectome. The connectome data of this meta-study of tract-tracing reports of the basal ganglia are available for further network studies, the integration into neocortical connectomes and further extensive investigations of the basal ganglia dynamics in population simulations.
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Affiliation(s)
- Oliver Schmitt
- Department of Anatomy, University of Rostock, Rostock, Germany.
| | - Peter Eipert
- Department of Anatomy, University of Rostock, Rostock, Germany
| | | | - Felix Leßmann
- Department of Anatomy, University of Rostock, Rostock, Germany
| | - Andreas Wree
- Department of Anatomy, University of Rostock, Rostock, Germany
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Falisi G, Rastelli C, Panti F, Maglione H, Quezada Arcega R. Psychotropic drugs and bruxism. Expert Opin Drug Saf 2014; 13:1319-26. [PMID: 25195948 DOI: 10.1517/14740338.2014.947262] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
INTRODUCTION Sleep and awake bruxism is defined as 'a parafunctional activity including clenching, bracing, gnashing, and grinding of the teeth'. Some evidence suggests that bruxism may be caused by, or associated with, alterations in the CNS neurotransmission. Several classes of psychotropic drugs interfering with CNS activity may potentially contribute to bruxism. Thus, the purpose of this study was to examine relevant peer-reviewed papers to identify and describe the various classes of psychotropic substances that may cause, exacerbate or reduce bruxism as the result of their pharmacological action in CNS neurons. AREAS COVERED A literature search from 1980 to the present was performed using PubMed database. The term 'bruxism' was used in association with 'psychotropic', 'dopamine (DA)', 'serotonin', 'histamine', 'antipsychotics', 'antidepressants', 'antihistaminergics' and 'stimulants'. EXPERT OPINION Studies on the effects of DA agonists (Levo-DOPA, psychostimulants) and antagonists (antipsychotics) identified a central role of DA in the pathogenesis of pharmacologically induced bruxism. Important information from studies on drugs acting on serotonin neurotransmission (antidepressants) was recognized. Other mechanisms involving different neurotransmitters are emerging. This is the case of antihistaminergic drugs which may induce bruxism as a consequence of their disinhibitory effect on the serotonergic system.
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Affiliation(s)
- Giovanni Falisi
- University of L'Aquila, School of Dentistry, Department of Life, Health, and Environmental Sciences , Piazzale Salvatore Tommasi 1, 67100 Coppito (AQ), L'Aquila , Italy +39 0862433202 ; +39 08624332 ;
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14
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Schwarz PB, Peever JH. Dopamine triggers skeletal muscle tone by activating D1-like receptors on somatic motoneurons. J Neurophysiol 2011; 106:1299-309. [PMID: 21653722 DOI: 10.1152/jn.00230.2011] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The dopamine system plays an integral role in motor physiology. Dopamine controls movement by modulation of higher-order motor centers (e.g., basal ganglia) but may also regulate movement by directly controlling motoneuron function. Even though dopamine cells synapse onto motoneurons, which themselves express dopamine receptors, it is unknown whether dopamine modulates skeletal muscle activity. Therefore, we aimed to determine whether changes in dopaminergic neurotransmission at a somatic motor pool affect motor outflow to skeletal muscles. We used microinjection, neuropharmacology, electrophysiology, and histology to determine whether manipulation of D(1)- and D(2)-like receptors on trigeminal motoneurons affects masseter and/or tensor palatini muscle tone in anesthetized rats. We found that apomorphine (a dopamine analog) activated trigeminal motoneurons and triggered a potent increase in both masseter and tensor palatini tone. This excitatory effect is mediated by D(1)-like receptors because specific D(1)-like receptor activation strengthened muscle tone and blockade of these receptors prevented dopamine-driven activation of motoneurons. Blockade of D(1)-like receptors alone had no detectable effect on basal masseter/tensor palatini tone, indicating the absence of a functional dopamine drive onto trigeminal motoneurons, at least during isoflurane anesthesia. Finally, we showed that D(2)-like receptors do not affect either trigeminal motoneuron function or masseter/tensor palatini muscle tone. Our results provide the first demonstration that dopamine can directly control movement by manipulating somatic motoneuron behavior and skeletal muscle tone.
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Affiliation(s)
- Peter B Schwarz
- Systems Neurobiology Laboratory, Department of Cell and Systems Biology, University of Toronto, 25 Harbord St., Toronto, ON M5S 3G5, Canada
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15
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Mascaro MB, Prosdócimi FC, Bittencourt JC, Elias CF. Forebrain projections to brainstem nuclei involved in the control of mandibular movements in rats. Eur J Oral Sci 2010; 117:676-84. [PMID: 20121930 DOI: 10.1111/j.1600-0722.2009.00686.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Mandibular movements occur through the triggering of trigeminal motoneurons. Aberrant movements by orofacial muscles are characteristic of orofacial motor disorders, such as nocturnal bruxism (clenching or grinding of the dentition during sleep). Previous studies have suggested that autonomic changes occur during bruxism episodes. Although it is known that emotional responses increase jaw movement, the brain pathways linking forebrain limbic nuclei and the trigeminal motor nucleus remain unclear. Here we show that neurons in the lateral hypothalamic area, in the central nucleus of the amygdala, and in the parasubthalamic nucleus, project to the trigeminal motor nucleus or to reticular regions around the motor nucleus (Regio h) and in the mesencephalic trigeminal nucleus. We observed orexin co-expression in neurons projecting from the lateral hypothalamic area to the trigeminal motor nucleus. In the central nucleus of the amygdala, neurons projecting to the trigeminal motor nucleus are innervated by corticotrophin-releasing factor immunoreactive fibers. We also observed that the mesencephalic trigeminal nucleus receives dense innervation from orexin and corticotrophin-releasing factor immunoreactive fibers. Therefore, forebrain nuclei related to autonomic control and stress responses might influence the activity of trigeminal motor neurons and consequently play a role in the physiopathology of nocturnal bruxism.
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Affiliation(s)
- Marcelo B Mascaro
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
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16
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Byrd KE, Romito LM, Dzemidzic M, Wong D, Talavage TM. fMRI study of brain activity elicited by oral parafunctional movements. J Oral Rehabil 2010; 36:346-61. [PMID: 19382299 DOI: 10.1111/j.1365-2842.2009.01947.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Parafunctional masticatory activity, such as the tooth clenching and grinding that is associated with bruxism, is encountered by clinicians in many disciplines, including dentistry, neurology and psychiatry. Despite this, little is known about the neurological basis for these activities. To identify the brain network engaged in such complex oromotor activity, functional magnetic resonance imaging (fMRI) was used to elucidate the brain activation patterns of 20 individuals (10 males and 10 females, mean s.d. age of 26.3+/-4.1 years) with (parafunctional, PFx group, 5M/5F) and without (normal functional, NFx group, 5 M/5F) self-reported parafunctional grinding and clenching habits during clenching and grinding tasks. Subject group classification was based on: (i) self-reported history, (ii) clinical examination, (iii) evaluation of dental casts and (iv) positive responses to the temporomandibular disorder (TMD) History Questionnaire [Dworkinand LeResche, Journal of Craniomandibular Disorders, (1992) 6:301]. While subjects performed these oromotor tasks, each wore a custom-designed oral appliance minimizing head motion during imaging. Mean per cent signal changes showed significant between group differences in motor cortical (supplementary motor area, sensorimotor cortex and rolandic operculum) and subcortical (caudate) regions. Supplementary motor area data suggest that motor planning and initiation, particularly during the act of clenching, are less prominent in individuals with oromotor parafunctional behaviours. The overall extent of activated areas was reduced in subjects with self-reported parafunctional masticatory activity compared with the controls. This study's methodology and findings provide an initial step in understanding the neurological basis of parafunctional masticatory activities that are relevant for therapeutic research applications of temporomandibular joint and muscle disorders and associated comorbidities.
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Affiliation(s)
- K E Byrd
- Department of Anatomy & Cell Biology, Indiana University School of Medicine, Indianapolis, IN 46202-5120, USA.
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Nurten A, Ozerman B, Ozen I, Kara I. The role of solid food intake in antimuscarinic-induced convulsions in fasted mice. Epilepsy Behav 2009; 15:142-5. [PMID: 19318134 DOI: 10.1016/j.yebeh.2009.03.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2009] [Revised: 03/16/2009] [Accepted: 03/18/2009] [Indexed: 10/20/2022]
Abstract
Animals treated with scopolamine after fasting develop convulsions after they are allowed to eat ad libitum. This study was aimed at investigating the effect on these convulsions of liquid food intake, feeding by gavage, and placebo. Fasted mice treated with saline or scopolamine were allowed to eat solid food, slurry food or liquid food ad libitum, given placebo, or given liquid food by gavage. After 30 min, all animals were allowed to eat food pellets and observed for 30 min for the incidence and onset of convulsions. Scopolamine treatment caused convulsions only in the animals given solid food in the first 30 min; no convulsions were observed in the animals given slurry food, liquid food ad libitum, gavage, or placebo. When the animals that did not develop convulsions during the experiment were allowed to eat solid food, convulsions occurred. These findings indicate that complex mechanisms trigger scopolamine-induced convulsions in fasted animals eating solid food.
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Affiliation(s)
- Asiye Nurten
- Institute for Experimental Medicine, Department of Neuroscience, Istanbul University, Istanbul 34280, Turkey.
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18
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Lavigne GJ, Khoury S, Abe S, Yamaguchi T, Raphael K. Bruxism physiology and pathology: an overview for clinicians. J Oral Rehabil 2009; 35:476-94. [PMID: 18557915 DOI: 10.1111/j.1365-2842.2008.01881.x] [Citation(s) in RCA: 449] [Impact Index Per Article: 28.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Awake bruxism is defined as the awareness of jaw clenching. Its prevalence is reported to be 20% among the adult population. Awake bruxism is mainly associated with nervous tic and reactions to stress. The physiology and pathology of awake bruxism is unknown, although stress and anxiety are considered to be risk factors. During sleep, awareness of tooth grinding (as noted by sleep partner or family members) is reported by 8% of the population. Sleep bruxism is a behaviour that was recently classified as a 'sleep-related movement disorder'. There is limited evidence to support the role of occlusal factors in the aetiology of sleep bruxism. Recent publications suggest that sleep bruxism is secondary to sleep-related micro-arousals (defined by a rise in autonomic cardiac and respiratory activity that tends to be repeated 8-14 times per hour of sleep). The putative roles of hereditary (genetic) factors and of upper airway resistance in the genesis of rhythmic masticatory muscle activity and of sleep bruxism are under investigation. Moreover, rhythmic masticatory muscle activity in sleep bruxism peaks in the minutes before rapid eye movement sleep, which suggests that some mechanism related to sleep stage transitions exerts an influence on the motor neurons that facilitate the onset of sleep bruxism. Finally, it remains to be clarified when bruxism, as a behaviour found in an otherwise healthy population, becomes a disorder, i.e. associated with consequences (e.g. tooth damage, pain and social/marital conflict) requires intervention by a clinician.
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Affiliation(s)
- G J Lavigne
- Faculty of Dentistry, Surgery Department, Pain, Sleep and Trauma Unit, Université de Montréal, Hôpital du Sacré-Coeur de Montréal, Montréal, Canada.
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Miwa H, Kubo T, Suzuki A, Kondo T. Effects of zonisamide on c-Fos expression under conditions of tacrine-induced tremulous jaw movements in rats: a potential mechanism underlying its anti-parkinsonian tremor effect. Parkinsonism Relat Disord 2008; 15:30-5. [PMID: 18693129 DOI: 10.1016/j.parkreldis.2008.02.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2008] [Revised: 02/18/2008] [Accepted: 02/18/2008] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To examine the mechanisms underlying the anti-tremor effect of zonisamide in rats under conditions of tacrine-induced tremulous jaw movements (TJMs). METHODS Male adult rats received systemic administration of either zonisamide (5 or 50mg/kg) or vehicle at 20min prior to the administration of tacrine hydrochloride (5mg/kg). Animals were sacrificed 2h later, and the brains collected and immunostained for quantitative assessment of c-Fos expression. RESULTS There was no effect of zonisamide on tacrine-induced c-Fos expression in the ventrolateral striatum, a primary site of the pharmacological action of tacrine. Zonisamide suppressed the tacrine-induced c-Fos expression in the cortex, the dorsal striatum, and the nucleus accumbens, which are involved in the architecture of the cortico-basal ganglia-thalamocortical circuits. CONCLUSION The anti-TJM effect of zonisamide may not relate to suppression of neural activity specifically in primary tremor-generating sites, but may be due to a more broad inhibitory effect on tremor-related structures such as the cortex or the striatum. This effect of zonisamide may be a contributing mechanism underlying its therapeutic efficacy on parkinsonian tremor.
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Affiliation(s)
- Hideto Miwa
- Department of Neurology, Wakayama Medical University, 811-1 Kimiidera, Wakayama City, Wakayama 641-8510, Japan.
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Desmons S, Graux F, Atassi M, Libersa P, Dupas PH. The lateral pterygoid muscle, a heterogeneous unit implicated in temporomandibular disorder: a literature review. Cranio 2007; 25:283-91. [PMID: 17983128 DOI: 10.1179/crn.2007.042] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Based on its anatomical relationships, the lateral pterygoid muscle is strongly linked with the temporomandibular joint (TMJ). It plays a major role in mastication. Embryological, histological, and anatomical knowledge define the lateral pterygoid muscle as a single muscle with a penniform structure. The various results of electromyographic (EMG) studies describe a complex physiology with a chronological contraction of the layers during the masticatory cycle. The sequential contraction of the layers of the lateral pterygoid muscle is the result of a selective neuronal activation induced by the masticatory Central Pattern Generator (mCPG). This neurophysiological theory highlights the essential role of the reticular formation in oral motor control. The sensitivity of those neurological structures to chronic emotional stress is one of the possible explanations for the appearance of oral parafunctions accompanied by a modification of pain perception and a disorganized muscular activation, determining factors in temporomandibular disorders.
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