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1
Brinkworth, Russell Stewart Anglesey. "Response of the human jaw to mechanical stimulation of teeth". Access PDF text via HTML index, 2004. http://hdl.handle.net/2440/37934.
Testo completoAbstract (sommario):
Animal experiments indicate that the main form of feedback for jaw-closing muscles is from periodontal mechanoreceptors (PMRs). However, due primarily to limitations on methods, this is yet to be confirmed in humans. The main aim of this thesis was to investigate the reflex contribution of PMRs to the human jaws using vertical (axial) stimulation. To this end the electromyographic and bite force responses of the jaw to a number of different mechanical stimulus conditions, delivered to both the upper central incisors and the upper right first molars, were investigated. The principal hypothesis was that PMRs are responsible for the majority of the reflex responses seen in the human jaw muscles. Furthermore this reflex response is modulated by different characteristics of the stimulus such as: rate of rise, maximum force applied, the amount of constant offset force (preload), the level of muscle contraction and also the physical characteristics of the subject's jaw including: dental health and tooth spacing. These studies have contributed towards the understanding of the neuronal wiring and the receptor systems contained in the jaw. The results indicate that PMRs around the incisors are of fundamental importance for the development of reflex patterns but little if any PMR related reflexes exist around the molar teeth. The reflexes originating from the PMRs around the incisors are modulated by different mechanical characteristics of the stimulus, thus helping to explain how the jaw muscles perform numerous and complex patterns of activation which move the jaw in many different ways and develop forces that are optimum for the task at hand.Thesis (Ph.D.)--School of Molecular & Biomedical Science, 2004.
2
Yang, Jun. "Reflex control of human jaw muscles by periodontal mechanoreceptors". Title page, contents and abstract only, 1999. http://web4.library.adelaide.edu.au/theses/09PH/09phy219.pdf.
Testo completoAbstract (sommario):
Copies of author's previously published articles inserted. Bibliography: leaves 169-219. Describes experiments to determine what factors affect the outcome of the reflex response of the jaw closing muscles to peridontal mechanoreceptive stimulus. The reflex responses of the human masseter were investigated by applying force using different stimulus profiles. It was shown that when the force profile had little or no fast component, the likelehood of eliciting an exitatory peridontal masseteric reflex increased. It is concluded that the shape of the stimulus profile, the location of the stimulating probe and the presence of preload are the main factors that determine the exitatory reflex response of the jaw closing muscles.
3
Grykuliak, Glenna M. "Electroymyographic data and post-exercise pain in female muscle pain and control subjects after experimental chewing". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0002/MQ34370.pdf.
Testo completo
4
Pearce, Sophie. "Motor cortical control of human jaw muscles : a thesis submitted for the degree of Doctor of Philosophy in the Department of Physiology, the University of Adelaide, Adelaide, South Australia /". Title page, table of contents and abstract only, 2002. http://web4.library.adelaide.edu.au/theses/09PH/09php3595.pdf.
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5
Santosa, Robert. "The influence of the leaf gauge on jaw muscles, EMG". Master's thesis, Faculty of Dentistry, 2001. http://hdl.handle.net/2123/4838.
Testo completoAbstract (sommario):
This work was digitised and made available on open access by the University of Sydney, Faculty of Dentistry and Sydney eScholarship . It may only be used for the purposes of research and study. Where possible, the Faculty will try to notify the author of this work. If you have any inquiries or issues regarding this work being made available please contact the Sydney eScholarship Repository Coordinator - ses@library.usyd.edu.au
6
Sae-Lee, Daraporn. "Effects Of Experimentally Induced Jaw Muscle Pain On Jaw Muscle Activity And Jaw Movement During Standardized Jaw Tasks". Thesis, The University of Sydney, 2007. http://hdl.handle.net/2123/4969.
Testo completo
7
Huang, Bor-Yuan. "The influence of an occlusal alteration on the working-side condylar movement and the activity of the jaw muscles during defined lateral jaw movements". Thesis, The University of Sydney, 2003. http://hdl.handle.net/2123/4837.
Testo completo
8
Holliday, Casey M. "Evolution and function of the jaw musculature and adductor chamber of archosaurs (crocodilians, dinosaurs, and birds)". Connect to this title online, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1147280827.
Testo completo
9
Moura, Ferreira Polyana. "Reorganization of jaw muscle activity during experimental jaw muscle pain". Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/18255.
Testo completoAbstract (sommario):
Background and Aims: Temporomandibular disorders are clinical conditions that often involve pain in the masticatory muscles, the temporomandibular jaw joint and/or associated structures. The association between muscle pain and muscle activity is often explained by uniform increases or decreases in motor unit activity throughout a muscle but recent evidence suggests more complex changes within a painful muscle. The general aim of this study was to determine if experimentally induced masseter muscle pain modifies temporalis muscle activity. Methods: 20 healthy participants received experimental pain through hypertonic saline (5% NaCl) infusion into the right masseter; pain intensity was maintained at 40-60/100 mm on a visual analogue scale (VAS). Standardized biting tasks were performed with an intraoral force transducer while single motor unit (SMU) activity was recorded from 2 intramuscular electrodes (right masseter and right temporalis). The tasks were repeated in 4 blocks: baseline 1, hypertonic saline infusion, isotonic saline infusion, baseline 2. Each block had 3 isometric biting tasks: a slow and a fast ramp jaw closing task and a 2 step-levels jaw closing task (2 force levels: step 1 and step 2). Results: 83 SMUs were discriminated from the temporalis and 58 from the masseter muscle. This study demonstrated that induced muscle pain in the right masseter can be associated with the activation of new SMUs and the silencing of other single motor units in the painful masseter muscle as well as in the right temporalis muscle, which did not receive noxious stimulation with the hypertonic saline. No differences between pain and no pain trials were found in thresholds and firing rates of SMUs from the temporalis muscle. Discussion and conclusion: The present findings are consistent with previous findings from the limb (Hodges and Tucker 2011; Tucker et al. 2009) and rather than supporting uniform increases or decreases in motor unit activity throughout a muscle, suggest that there is a reorganization of motor unit activity across the entire jaw motor system in experimental pain.
10
Wessel, Tim van. "Daily activity of developing jaw muscles". [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2006. http://dare.uva.nl/document/19281.
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11
Korfage, Joannes Antonius Maria. "Myosin heavy chain composition of the human jaw muscles". [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2004. http://dare.uva.nl/document/75060.
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12
Watson, Catherine. "Descending neural control of the human masseter". Thesis, University of Newcastle Upon Tyne, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285393.
Testo completo
13
Tortopidis, Dimitrios Steliou. "Bite force and EMG studies on the jaw-closing muscles". Thesis, University of Glasgow, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361012.
Testo completo
14
Amhamed, Magda. "Effects of experimental pain in one and two jaw muscles on the functions of jaw motor system". Thesis, The University of Sydney, 2014. http://hdl.handle.net/2123/12873.
Testo completoAbstract (sommario):
Stretch-induced muscle damage is a condition resulting in force decline in skeletal muscle after eccentric contractions. The exact mechanisms underlying this decline is unclear but has been attributed to EC-coupling failure. Both μ-calpain and junctophilin-1 are activated during eccentric contractions in single fibres and isolated muscle, however no studies have shown this in blood-perfused muscle. This study used an in vivo model to investigate the roles of μ-calpain and JP-1 in force decline of the tibialis anterior (TA) muscle of wild-type and mdx mice (model for Duchenne muscular dystrophy) during eccentric contractions. The hypothesis was that eccentric contractions would cause calcium influx through stretch-activated channels (SACs) thereby activating μ-calpain and JP-1, disrupting EC-coupling and thus force production. The TA was subjected to 20 eccentric contractions during supramaximal activation and removed after a 30 min recovery. Western blotting was used to detect protein activity. The results show force decline during eccentric contractions is associated with JP-1 proteolysis, but not μ-calpain autolysis. The SAC blocker, streptomycin, was effective in improving force during eccentric contractions but had no effect on JP-1 proteolysis in mdx mice, whilst a second SAC blocker, anti-TRPC-1, had no effect. The results suggest under more physiological conditions, JP-1 proteolysis is independent of calcium influx through SACs and is more likely due to mechanical damage or reactive oxygen species induced SR-calcium release.
15
Connaghan, Kathryn P. "Jaw stiffness during speech by children with suspected hypo- or hypertonia /". Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/8206.
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16
Davies, Sarah Elyse. "The Effects of a Jaw-Opening Exercise on Submental Muscles and Hyoid Movement During Swallowing in Healthy Adults". Thesis, University of Canterbury. Communication Disorders, 2012. http://hdl.handle.net/10092/6999.
Testo completoAbstract (sommario):
Objective: Traditionally, swallowing rehabilitation has involved the use of muscle strengthening exercises, such as the head-lift manoeuvre (Shaker et al., 1997), to strengthen the floor of mouth muscles. Clinical reasoning suggests that this particular exercise may be problematic for patients with cervical spine injuries or increased frailty. Recently, Bauer and Huckabee (2010) attempted to determine the efficacy of an alternative exercise for the floor of mouth muscles in healthy adults. The present study aims to expand on this work in a larger population of healthy adults.
Study design: Controlled trial; participants matched for age and sex.
Participants: 23 healthy adults with no history of neurological or muscular impairment.
Method: Participants were assigned into one of two groups: jaw opening exercise (JOE; n = 12) and sham exercise (SE; n = 11). Groups were matched for age and gender. Participants performed their respective exercises three times per day, five days per week, over a six week period. At three times during this period, measures of submental 2-D cross-sectional area and anterior hyoid movement were taken via ultrasound. Additionally, measures of submental muscle myoelectrical activity were taken via surface electromyography. Pre- and post-treatment comparisons, as well as inter-group comparisons, were undertaken.
Results: No significant differences were observed between groups on measures of muscle size, anterior hyoid movement, or myoelectrical activity over time. However, this study has contributed to the future development of an alternative exercise to target the submental muscle group.
17
Alibrahim, Anas. "The measurement of maximal bite force in human beings". Thesis, University of Dundee, 2015. https://discovery.dundee.ac.uk/en/studentTheses/73283c8a-eee6-468b-8300-b79c12ad9f51.
Testo completoAbstract (sommario):
Background: Registering a true maximum bite force on the most commonly-used force transducers is problematic. It is often believed that this is related mainly to discomfort and the fear of breaking teeth. Objectives: The aim of the project was to compare the suitability of different bite force measuring transducers including ones which were designed to improve subject comfort. The transducers used were a traditional strain-gauge transducer with and without covering with ethylene vinyl acetate (EVA) sheets, and a newly-developed pressure transducer. Methods: Five separate studies were performed in this project. The experiments were carried out on human volunteer subjects (aged 24 to 41 years). They were all dentate with no missing anterior teeth and with no crowns on these teeth. The following procedures were used in some or all of the studies: measurement of MVBF, electrical stimulation of the masseter muscle, and EMG recording from two pairs of jaw closing muscles. Results: The highest MVBF values were recorded on the pressure transducer, mean (± S.D.) 464 N ± 224 N; followed by the strain-gauge transducer with EVA sheets, 243 ± 80 N; and last of all the strain-gauge transducer with silicone indices, 165 ± 35 N; or acrylic indices, 163 ± 82 N. Significantly higher maximum potential bite forces were predicted by twitch interpolation for the pressure transducer (730 ± 199 N) than for the strain-gauge transducer with EVA sheets, 354 ± 67 N (Paired t test, P < 0.05). Significantly higher EMGs of the masseter and anterior temporalis muscles were found to be associated with MVBFs on the pressure transducer than with MVBFs on the strain-gauge transducer with EVA sheets (Paired t test, P < 0.05). Conclusions: It is concluded that: a) the pressure transducer system and to a lesser extent the strain-gauge transducer covered with EVA sheets seemed to overcome the fear associated with biting on the hard surfaces of the strain-gauge transducer alone; b) the pressure transducer may have some multi-directional capabilities which allow for total bite forces, or at least larger parts of them, to be recorded than on a uni-directional strain-gauge transducer.
18
Fartash, Lida. "Masticatory muscle volume and function in migraineurs". Thesis, Queen's University Belfast, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247365.
Testo completo
19
Whittle, Terry Evelyn. "The psychophysiological effects of stress in chronic jaw muscle pain". Thesis, The University of Sydney, 2014. http://hdl.handle.net/2123/12461.
Testo completoAbstract (sommario):
Chronic jaw muscle pain is the most commonly diagnosed condition in temporomandibular disorders with 10.1% of the Australian population displaying symptoms. The present study proposed to investigate the effect of biological and behavioural responses to different stressors on the function of jaw muscles of participants with chronic jaw muscle pain through two experiments. In the first experiment, two chronic pain groups and a pain free group identified stressful daily events (daily hassles) for frequency and severity. Significant difference between the groups was shown for severity but not frequency with highest scores relating to health daily hassles. The second study assessed the effect of two stressors on jaw movement and muscle activity in chronic jaw muscle pain participants compared to controls. All participants undertook open/close jaw movements, free gum and standardised gum chewing movements. No significant difference between the groups was reported for movement amplitude and velocity of the jaw movements after the stressors. Of the five jaw muscles recorded during movement only one was significantly different between the groups after the stressors. Grouped data from all participants showed a significant effect of stressor for most of the jaw movement parameters and for jaw muscle activity across various muscles and stressors. Differences in the current study compared to previous studies may be that the chronic jaw muscle pain group were not dissimilar to the control group although clinically diagnosed as TMD and reporting jaw muscle pain throughout the experiment. The results do not support the current jaw muscle pain or stress models although the data are consistent with pain leading to a redistribution of motor unit activation within and between muscles. The results of the current study have identified inconsistencies with previous studies and highlighted the complex interrelationship between pain and stress that need further exploration.
20
Saed, Hassan Hantosh. "A study of receptors in jaw muscles of the rat and other vertebrates". Thesis, Durham University, 1989. http://etheses.dur.ac.uk/6565/.
Testo completoAbstract (sommario):
The masseteric nerve supplying rat deep masseter muscle was traced from serial paraffin sections. The number of myelinated axons counted in a plastic transverse section close to its entrance into the muscle was 2120. Extrafusal muscle fibre counts of rat deep masseter (71,400 fibres) and anterior digastric (5,400 fibres) muscles have been performed and were found to be 2 to 3 times higher than Hiiemae's count (1971). The number of muscle spindles in deep masseter ranged from 86 to 134 and were mostly distributed in an anterior cluster. Using glyoxylic acid-induced fluorescence, the extrafusal muscle fibres of deep masseter and anterior digastric muscles were found to be adrenergically innervated, in the respective proportions of 40% and 55%. It was found that some spindle capsules (about one third) received such innervation at their equatorial region. According to histo- eind immunohistochemical reactions, the masseter muscle is uniformly composed of type IIA fibres, except for a small number of slow oxidative fibres which were restricted to spindle-cluster areas. Three types of intrafusal muscle fibre similar to those in rat hindlimb muscle were recognized. The morphology of muscle spindles in deep masseter muscle was studied with light microscopy using serial plastic sections. The number of intrafusal muscle fibres was found to range from 2 to 7, usually one bag(_1), one bagg(_2) and 2-5 chain fibres. The lengths and diameters of the intrafusal muscle fibres and the capsules were obtained. The length of spindles ranged from 950 to 4000 µm and that of capsules from 400 to 2600 µm. The innervation of anterior cluster muscle spindles in deep masseter muscle and spindles in some hindlimb muscles of the rat was studied in teased, silver impregnated material. Analysis of the sensory innervation revealed the following unusual or unique features: a high number of afferents (1-6) innervating the sensory region of each spindle; some la axons branched to supply primary endings to two bagj fibres in two separate spindles; some other la axons branched to supply primary and secondary endings in the same spindle; and some group II axons branched to supply two secondary endings in the same spindle. Some motor axons were found to be branched to supply small end plates to bagi fibres of some spindles in the anterior cluster, and therefore it is concluded here that some cluster spindles in deep masseter muscle receive dynamic β innervation. A comparative study of the occurrence of muscle spindles in jaw- closing muscles of other vertebrates revealed that they are present in frog and absent from newt and salmon.
21
Nozad, Mojaver Yalda. "A FUNCTIONAL ANALYSIS OF THE MEDIAL PTERYGOID MUSCLE DURING JAW CLOSING AND HORIZONTAL FORCE IN HUMANS". Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/18260.
Testo completoAbstract (sommario):
There is limited information regarding the normal function of the medial pterygoid (MP) muscle, a major jaw muscle. The aims of our study were to develop a methodology to record from the MP during standardized isometric jaw closing tasks, to determine the range of tasks over which activity can be recorded in the MP, and to determine whether there is evidence for functional heterogeneity within the MP muscle by comparing electromyographic (EMG) features in different regions of the MP. Fifteen healthy participants were included in the study. The EMG activity of the right MP was recorded with intramuscular electrodes during the performance of isometric jaw closing tasks onto a force transducer as well as isometric contralateral (i.e. to the left side), protrusive (straightforward) and ipsilateral (i.e. to the right side) jaw tasks using another force transducer in the same participants. The isometric tasks were ramp tasks (at a fast rate and at a slow rate) and step level tasks (at 2 force levels). A computed tomography (CT) scan was performed for all participants and the presence of MP activity, thresholds of single motor units, and root means square (RMS) activity were assessed in the tasks. The MP was active in all jaw closing tasks in all participants, but in the horizontal tasks, the MP was mostly active in the protrusive and contralateral tasks (85% of participants), while it was activated in 57% of the participants in the ipsilateral tasks. The mean force threshold value for the fast jaw closing ramp task was significantly (P<0.05) lower than for the slow jaw closing ramp task. However the differences were not significant for any of the horizontal tasks. The EMG activity of the MP in all jaw closing and horizontal tasks was positive except for the ipsilateral tasks when the MP was not active in the ipsilateral tasks at all. CT scan verifications of the electrodes locations suggest a more important role for the lateral part of the MP in the generation and/or control of the horizontal jaw force tasks than the medial part. Also, a crucial role for the medial part in the vertical jaw closing tasks is proposed. These findings support the functional heterogeneity of the MP due to its selective activation in various tasks. This study proposes an important role for the MP in the generation of closing and lateral forces and also supports a role for the MP as being functionally heterogeneous.
22
EDUARDO, LUIS R. de P. "Terapia laser em baixa intensidade no tratamento da dor e disfuncao da articulacao temporomandibular e dos musculos mastigatorios: analise eletromiografica, biometrica e de dor". reponame:Repositório Institucional do IPEN, 2001. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10957.
Testo completoAbstract (sommario):
Made available in DSpace on 2014-10-09T12:46:05Z (GMT). No. of bitstreams: 0Made available in DSpace on 2014-10-09T14:02:09Z (GMT). No. of bitstreams: 1 07534.pdf: 4371715 bytes, checksum: 9ec1fe68c7fae9017a80251be5a75572 (MD5)
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
23
Atassi, Mounir. "Mechanical monitoring of inhibitory jaw reflexes in health and simulated dysfunction". Thesis, University of Dundee, 2014. https://discovery.dundee.ac.uk/en/studentTheses/abca297e-8951-447b-8c9e-0bb529d211a9.
Testo completoAbstract (sommario):
Objectives: Previous studies in the Oral Neurophysiology Laboratories in Dundee have defined the electromyographic properties of the inhibitory jaw reflex that can be evoked in human subjects by electrical stimulation of the lip. This reflex, in contrast with the more widely studied biphasic inhibitory reflexes evoked by stimulation of intra-oral nerves, consists of just a single phase of inhibition and usually requires the application of stimuli which excite nociceptive nerves. The aims of the present studies were to define the mechanical manifestations of this reflex in the form of changes in biting forces, and to investigate whether the mechanical manifestation of the inhibitory jaw reflex evoked by stimulation of the human upper lip, can be modulated by experimentally-controlled conditions that mimic symptoms of a myogenous temporomandibular disorder. Methods: Three series of experiments were performed on 49 volunteer subjects in total. The experiments involved recording bite forces between the anterior teeth and electromyograms (EMGs) from the masseter muscles. Transcutaneous electrical stimuli were applied to the hairy skin of upper lip while the subjects maintained a biting force of around 50N with the aid of visual feedback. In the first series of experiments, a range of electrical stimuli below and above the nociceptive threshold was delivered. In the second set of experiments, double stimuli with a range of different inter-stimulus intervals were applied. Finally in a third series of experiments, electrical stimulation was repeated before, immediately after, and 5 and 10 minutes following a 3-minute accelerated chewing task. This task consisted of chewing 1.5g of a tough chewing gum at 1.5 times the subject’s natural chewing rate and in 18 cases, muscle fatigue and/or pain were reported by the subjects. Results: Following stimulation at intensities that were described as sharp or painful, all the subjects showed both a suppression of the masseter EMG and a reduction of biting force. When analysing the maximum responses in each subject, the mean reduction in the EMG inhibition was to 15.78 ± 14.4% and 10.39 ± 7.92% of the baseline (for the ipsi- and contra-lateral EMGs respectively), whereas the biting force was reduced only to 83.98 ± 11.04% of baseline (+ S.D.). The latencies of onset of these responses were: 38.17 ± 3.58ms, 38.97 ± 4.49ms and 51.83 ± 6.23ms respectively. The response observed in the force record was weaker than in that observed in either EMG (Paired t tests, P < 0.005 in both cases). When applying double stimuli, it was found that the prolongation of the EMG inhibitory jaw reflex (to 144.70 ± 46.93% of the control level) evoked by double stimulation of the upper lip (with a 10 ms inter-stimulus interval) resulted in a greater increase in the depth of the accompanied relaxation (to 223.63 ± 70.88% of that seen in the control responses) compared to a relatively smaller increase in the duration of the relaxation (to 128.32 ± 27.23% of that seen in the control responses). Following the accelerated chewing task, 17 out of 22 subjects reported pain and/or fatigue in one or both of the masseter muscles. The integral for the bite force relaxation significantly decreased in size immediately following the conditioning procedure (to 76.04 ± 35.63% of the control level, P = 0.014; single sample t-test with Bonferroni correction, test value 100). Conclusion: The inhibitory jaw reflex evoked by stimulation of the human lip can be demonstrated mechanically as well as electromyographically although the mechanical version of the response appears less marked. In addition to that, the onset of reflex relaxation in bite force lags several milliseconds behind the corresponding reductions in electromyographic activity. The depth of force relaxation can be increased by increasing the duration of EMG recorded inhibitory reflex. Finally, the results from a chewing task suggest that induced acute pain and/or fatigue cause clear changes in the mechanical manifestation of this inhibitory jaw reflex.
24
McGregor, Neil Roland. "An investigation of the association between toxin producing staphylococcus, biochemical changes and jaw muscle pain". University of Sydney. Prosthetic Dentistry, 2000. http://hdl.handle.net/2123/369.
Testo completoAbstract (sommario):
Objectives: To assess the expression of the symptoms of jaw muscle pain and its association with alterations in biochemistry, other symptoms and the carriage of staphylococci. Methods: Three different study populations were assessed. The first was selected and examined by the author and consisted of 43 pain and 41 age and sex matched controls. The second was a study of CFS patients who were blinded to the author and the author subsequently examined the associations between jaw muscle symptom reporting and the standardised biochemistry measures. The third study was also blinded to the author but included an investigation of staphylococci and certain cytokine and biochemistry measures. Results: The three studies clearly establish an association between the carriage of toxicogenic coagulase negative staphylococci and the expression of jaw muscle pain in both males and females. These associations were homogeneous and were found whether the patients were selected on the basis of having jaw muscle pain or selected from within a population of patients selected on the basis of having Chronic Fatigue Syndrome. The studies associated the changes with variations in biochemistry and these were in turn associated with symptom expression within the jaw muscle pain patients. These biochemical alterations included the dysregulation of immune cell counts, cytokines, electrolyte and protein metabolism. These symptoms and biochemical changes were associated with pain severity and illness duration and staphylococcal toxin production. From the data a model was developed which shows the mechanisms involved in the development of chronic pain in the jaw muscles. Conclusions: The carriage of toxicogenic coagulase-negative staphylococci were found to be associated with the expression of jaw muscle pain and the alterations in biochemistry associated with these symptoms.
25
John, Verity Jayne. "The time course of naloxone-induced recurrence of mustard oil-evoked jaw muscle electromyographic activity". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0026/MQ40867.pdf.
Testo completo
26
McGregor, Neil Roland. "An Investigation Of The Association Between Toxin-Producing Staphylococcus Biochemical Changes And Jaw Muscle Pain". Thesis, The University of Sydney, 1999. http://hdl.handle.net/2123/4697.
Testo completoAbstract (sommario):
Doctor of PhilosophyThis work was digitised and made available on open access by the University of Sydney, Faculty of Dentistry and Sydney eScholarship . It may only be used for the purposes of research and study. Where possible, the Faculty will try to notify the author of this work. If you have any inquiries or issues regarding this work being made available please contact the Sydney eScholarship Repository Coordinator - ses@library.usyd.edu.au
27
McGregor, Neil Roland. "An Investigation Of The Association Between Toxin-Producing Staphylococcus Biochemical Changes And Jaw Muscle Pain". University of Sydney, 1999. http://hdl.handle.net/2123/4697.
Testo completoAbstract (sommario):
Doctor of PhilosophyThis work was digitised and made available on open access by the University of Sydney, Faculty of Dentistry and Sydney eScholarship . It may only be used for the purposes of research and study. Where possible, the Faculty will try to notify the author of this work. If you have any inquiries or issues regarding this work being made available please contact the Sydney eScholarship Repository Coordinator - ses@library.usyd.edu.au
28
McGregor, Neil Roland. "An investigation of the association between toxin producing staphylococcus, biochemical changes and jaw muscle pain". Thesis, The University of Sydney, 1999. http://hdl.handle.net/2123/369.
Testo completoAbstract (sommario):
Objectives: To assess the expression of the symptoms of jaw muscle pain and its association with alterations in biochemistry, other symptoms and the carriage of staphylococci. Methods: Three different study populations were assessed. The first was selected and examined by the author and consisted of 43 pain and 41 age and sex matched controls. The second was a study of CFS patients who were blinded to the author and the author subsequently examined the associations between jaw muscle symptom reporting and the standardised biochemistry measures. The third study was also blinded to the author but included an investigation of staphylococci and certain cytokine and biochemistry measures. Results: The three studies clearly establish an association between the carriage of toxicogenic coagulase negative staphylococci and the expression of jaw muscle pain in both males and females. These associations were homogeneous and were found whether the patients were selected on the basis of having jaw muscle pain or selected from within a population of patients selected on the basis of having Chronic Fatigue Syndrome. The studies associated the changes with variations in biochemistry and these were in turn associated with symptom expression within the jaw muscle pain patients. These biochemical alterations included the dysregulation of immune cell counts, cytokines, electrolyte and protein metabolism. These symptoms and biochemical changes were associated with pain severity and illness duration and staphylococcal toxin production. From the data a model was developed which shows the mechanisms involved in the development of chronic pain in the jaw muscles. Conclusions: The carriage of toxicogenic coagulase-negative staphylococci were found to be associated with the expression of jaw muscle pain and the alterations in biochemistry associated with these symptoms.
29
Chen, Hui. "A study of the functional properties of single motor units at computed-tomography-verified sites within the human medial pterygoid muscle during jaw movements". Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/16892.
Testo completoAbstract (sommario):
A detailed understanding of the functions of the jaw muscles is essential for the description of normal function as well as how the jaw motor system accommodates to perturbations such as chronic pain states as well as surgical and prosthodontic interventions. While the functional properties of many jaw muscles, such as the masseter and temporalis muscles, and to a lesser extent the lateral pterygoid muscle, have been intensively investigated, the medial pterygoid (MPt) muscle has been much less well studied. The broad aims of this study were to: 1. to develop a methodology for recording activity from the MPt muscle from locations that have been verified by computed tomography (CT). 2. to identify the functional properties of single motor units (SMUs) recorded from the MPt muscle during standardized horizontal and vertical jaw movement tasks, and to determine whether movement velocity would affect motor unit activation. 3. to assess the relation between CT-verified locations and SMU activities to determine if there exists evidence for functional heterogeneity within the MPt muscle. Twenty participants (10 males and 10 females, mean age: 25 years old) performed 8 tasks: 1) resting, 2) swallowing, 3) ipsilateral movement, 4) contralateral movement, 5) protrusive movement, 6) opening–closing movement, 7) unilateral chewing with gum, 8) bilateral maximal clenching. The ipsilateral, contralateral, protrusive and opening – closing movement tasks were performed with a goal-directed, visual feedback system at slow and fast speeds, and each of these tasks was divided into BEFORE, OUT, HOLDING, RETURN and AFTER phases according to the movement trajectories and SMU analysis was conducted in the 4 goal-directed movements only. Electromyographic (EMG) activities of the right MPt were recorded in resting (in 8 of the 20 participants), swallowing (12/12), ipsilateral movement (16/20), contralateral movement (20/20), protrusion (19/20), opening – closing movement (11/20), chewing (20/20) and clenching (20/20) tasks. Increased EMG activity was consistently found in the OUT, HOLDING and RETURN phases of the contralateral and protrusive movement tasks, regardless of the actual movement direction. An increased activity in the RETURN phase of the ipsilateral movement task in most participants, together with the presence of increased activity in the OUT phase of contralateral task in all participants, indicates an important role for the MPt in the generation of a contralateral force vector. The presence of EMG activity in 8 participants during the resting task and increased EMG activity in the RETURN phase of the opening – closing task (i.e. closing movement) suggest its active role in supporting the lower jaw against gravity. The absence of EMG activity in the MPt in 9 participants during all 3 phases of opening – closing movement tasks indicates the certain compartments of the MPt may not be involved in the closing movement. Of the 60 SMUs that were identified in the 4 goal-directed movement tasks, thresholds could be identified in relation to displacement in 46 SMUs. During the OUT phase of the contralateral (p < 0.001) and the RETURN phase of the ipsilateral (p < 0.001) movement tasks, thresholds were found to increase significantly with increases of movement velocity, although the strength of these correlations were weak. Previous studies of the lateral pterygoid muscle in contralateral and protrusive tasks have shown stronger inverse relations between threshold and speed, and this supported a role for the lateral pterygoid muscle as the main agonist driving the movement in these tasks. The present MPt data showing a direct, although weak, relation between speed and threshold are suggestive that the MPt muscle may be more involved in stabilizing the lower jaw rather than initiating the movement during contralateral and protrusive jaw movements. CT scanning was performed in 18 participants. Eight, 10, 25 and 14 SMUs with thresholds were identified in the anterolateral, anteromedial, posterolateral and posteromedial divisions, respectively. The MPt EMG pattern was found to vary between participants whose recording sites were identified in the same division and across different divisions. Significant differences were found between the thresholds and the 4 divisions during the OUT phases of contralateral (p < 0.0001) and protrusive (p = 0.0003) movement tasks. In the OUT phase of the contralateral movement, the thresholds in the anterolateral division were significantly lower than the other three divisions (p < 0.01). In addition, the thresholds of the SMUs identified in the anteromedial division in the OUT phases of both contralateral (p < 0.01) and protrusive (p < 0.01) movement tasks were significantly higher than the other 3 divisions in each task, respectively. These data support the concept that functional subcompartments exist within the MPt muscle. In conclusion, this is the first detailed investigation of the functional properties of SMUs recorded at CT-verified sites within the human MPt. The evidence suggests that the MPt muscle is a complex muscle involved in the fine control of low forces as required for the stabilization of vertical mandibular position throughout horizontal jaw movements. This muscle, consistent with findings from the other jaw muscles, shows evidence for functional heterogeneity.
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Österlund, Catharina. "Extra- and intrafusal muscle fibre type compositions of the human masseter at young age. : In perspective of growth and functional maturation of the jaw-face motor system". Doctoral thesis, Umeå universitet, Klinisk oral fysiologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-46667.
Testo completoAbstract (sommario):
Muscles control body posture and movement by extrafusal and intrafusal (muscle spindle) fibres. The purpose of this thesis was to provide insight into the muscular basis for human jaw function at young age. Extrafusal and intrafusal fibres in the young masseter, and for comparison young biceps, were examined for composition of fibre types and myosin heavy chain (MyHC) isoforms by means of morphological, enzyme-histochemical, biochemical and immuno-histochemical techniques. For evaluation of plasticity during life span the data for young muscles were compared with previous reported data for adult and elderly muscles. The results showed significant differences in extrafusal fibre types and MyHC expression between young masseter and young biceps and between young masseter and masseter in adults and elderly. Compared with young biceps, young masseter was more intricate in composition of extrafusal MyHC expression. Muscle spindles were larger and more frequent in the masseter than in the biceps. Masseter and biceps muscle spindles showed fundamental similarities but also marked differences in MyHC expression. The results suggest that the young masseter is specialized in fibre types already at young age and shows a unique fibre type growth pattern. Whereas masseter extrafusal fibres display marked plasticity in fibre types and MyHC isoforms during life span muscle spindles/intrafusal fibres are morphologically mature already at young age and precede extrafusal fibres in growth and maturation. Results showed similarities in intrafusal MyHC expression between young masseter and biceps, but also differences implying muscle specific proprioceptive control. Differences in fibre types and MyHC expression between young masseter and young biceps extrafusal fibres are proposed to reflect diverse evolutionary and developmental origins and accord with the masseter and biceps being separate allotypes of muscle.
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LOLLATO, R. F. "Contribuicao do Laser em Baixa Intensidade e da Ortopedia Funcional dos Maxilares no tratamento da dor e disfuncao temporo-mandibular". reponame:Repositório Institucional do IPEN, 2003. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11333.
Testo completoAbstract (sommario):
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Dissertacao (Mestrado Profissionalizante em Lasers em Odontologia)
IPEN/D-MPLO
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Malik, Bushra. "The effect of noxious stimulation of the right masseter muscle on single motor unit activity at two sites in the masseter muscle during standardized jaw closing tasks". Thesis, The University of Sydney, 2016. http://hdl.handle.net/2123/15573.
Testo completoAbstract (sommario):
Background and aims: The Pain Adaptation Model and the Vicious Cycle Theory are older theories of the effects of pain on motor activity. While some data sets are consistent with these theories, other data sets are not, and a number of new models (the Integrated Pain Adaptation Model; Theory of Motor Adaptation to Pain) have been proposed. Two of these models propose a reorganization of motor activity in pain. The aim of the present study was to determine whether experimental masseter muscle pain resulted in a change in muscle activity at two different sites within the masseter muscle during the performance of isometric jaw-closing tasks in asymptomatic participants. Methods: Single motor unit (SMU) activity was recorded with bipolar fine wire electrodes at 2 sites within the right masseter muscle during the performance of standardized isometric biting on an intraoral force transducer in 17 healthy participants. Participants performed standardized biting trials during infusion of 5% hypertonic saline into the right masseter (pain), and during isotonic saline infusion (control). Recruitment patterns, force thresholds and firing rates were compared between pain and control trials. Results: A total of 50 SMUs were discriminated from the 2 sites. Changes in recruitment patterns of SMUs at one site within the masseter muscle during pain in comparison with control was observed during the tasks and some of these changes were different to the changes occurring at the other site. There were no changes in thresholds of SMU firing nor in SMU firing rates between pain and control trials. Inter-individual variability in the motor response to pain was observed at the two different sites of the masseter. Discussion and Conclusions: In general, the data are not consistent with the earlier models of pain-motor interactions, but provide support for more recent models proposing a re-organization of motor activity in the presence of pain.
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Tsai, Chih-Mong. "Central neural pathways involved in craniofacial nociceptive reflex responses evoked in jaw muscles by mustard oil injection into the temporomandibular joint region". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0018/NQ28072.pdf.
Testo completo
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Semeghini, Tatiana Adamov. "Estudo eletromiografico do padrão de co-ativação do musculo esternocleidomastoideo em diferentes movimentos mandibulares". [s.n.], 2002. http://repositorio.unicamp.br/jspui/handle/REPOSIP/290207.
Testo completoAbstract (sommario):
Orientador: Vanessa Monteiro PedroTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: Embora a co-ativação da musculatura cervical durante a movimentação da mandíbula tenha sido estudada na literatura, esta situação ainda é pouco descrita quando comparados voluntários clinicamente normais e portadores de disfunções musculares. O objetivo deste trabalho foi estudar eletromiograficamente a co-ativação bilateral do músculo esternocleidomastoideo em relação aos Mm. Da mastigação em voluntários clinicamente normais e em portadores de bruxismo. Para a coleta do sinal mioelétrico foi utilizado um eletromiógrafo (*Lynx Eletronics) formado por um módulo condicionador de sinais de 12 bits de resolução, filtro tipo Butterworth (10,6 - 509 Hz) com ganho de 100 vezes, e placa conversora A/D, colocado dentro de uma Gaiola Eletrostática de Faraday. O registro mioelétrico foi realizado pelo software Aqdados, com apresentação simultânea dos canais usados e freqüência de amostragem de 1000 Hz, instalado em um computador 486 DX padrão. O sinal foi captado por eletrodos ativos diferenciais simples, formados por duas barras retangulares de prata paralelas, espaçadas por 10mm. e fixas entre si. A impedância de entrada dos eletrodos foi de 10G¿OMEGA¿, CCMR de 130 dB e 2pF, com ganho de 100 vezes. Foram também utilizados no estudo: eletrodo de referência; esparadrapos impermeáveis; Parafilme M (American National Can TM); metrônomo (Picollo - Winter), régua milimetrada. O sinal eletromiográfico foi coletado em três situações: a) isotonia dos músculos da mastigação; b) CIVM dos músculos da mastigação; c) CIVM do M. ECM. Os dados foram avaliados estatisticamente pelos testes ANOVA - Medidas Repetidas e Teste T para dados não pareados, de acordo com a situação estudada. Os resultados evidenciaram a presença da co-ativação do M. ECM em ambos grupos estudados e a análise dos valores médios de RMS bruto dos Mm. da mastigação revelou diferenças estatisticamente significativas entre os entre os grupos estudados nas variáveis músculos, lados e situações, validando os critérios de inclusão da amostra adotados nesta pesquisa. Em voluntários clinicamente normais, a ativação do M. ECM foi significativamente menor durante a isotonia que na isometria dos Mm. da mastigação, enquanto que em portadores de bruxismo, estas diferenças não foram verificadas. Na CIVM dos Mm. da mastigação, evidenciou-se uma diminuição das porcentagens bilaterais de co-ativação do M. ECM em relação à porção anterior do M. temporal, além da diminuição da ativação do músculo masseter e um aumento da ativação do músculo temporal em portadores de bruxismo, quando. comparados aos voluntários clinicamente normais. Comparando os valores de ativação do M. ECM nos movimentos mandibulares à sua CIVM, verificou-se uma diminuição de ativação muscular do lado direito em voluntários portadores de bruxismo. Os resultados desta pesquisa, sob suas condições experimentais realizadas, permitiram concluir que houve co-ativação do M. esternocleidomastoideo durante a movimentação mandibular e que esta parece sofrer influência das alterações dos músculos da mastigação em voluntários portadores de bruxismo, embora seja perceptível a necessidade de realização de mais estudos sobre o tema
Abstract: Although cervical muscles co-activation during jaw movements has been studied, this verification is stilllittle described in literature when are compared healthy subjects and patients with muscular dysfunction. The aim of this study was to verify by surface electromyography the bilateral co-activation of the sternocleidomastoid (SCM) muscle regarding to chewing muscles in healthy and bruxism volunteers. To record myoelectric signs, has been used a 16 channel signal conditioner with 12 bits dynamic band resolution (*Lynx Eletronics), Butterworth-type band pass filter (10,6-509 Hz) with gain of 100 times, and A/D converter board, placed inside of an Electrostatic Cage of Faraday. The myoelectric signs were displayed through by Aqdados Software installed in an Ibm-pc 486 DX2, that have showed simultaneous presentation of the used channels, each one with frequency of sampling of 1000 Hz. The signal was caught by simple active electrodes, formed by two rectangular and parallel silver bars, spaced for 10 mm. and fixed between it. The electrodes impedance of input was of 10G, 130 dB of CMRR and 2pF, with 100 times of gain. The materiaIs also used in this study were: reference electrode; adhesive tapes; Parafilm-M (American National Can¿POT. TM¿),metronome (Picollo-Winter) and milimetric ruler. The myoelectric signal was collected in three positions: a) chewing movements; b) clenching movements; c) isometric contraction of SCM muscles. The data has been evaluated statistically by ANOVA-repeated measures and impaired T tests, on accordance with the studied situation. The results have evidenced the presence of SCM coactivation in both groups and the analysis of RMS average values by chewing muscles have showed significant statistical differences between groups referring muscles, sides and situations analyzed, witch may be valid the criteria of sample inclusion adopted on this research. In healthy volunteers, the SCM co-activation was significantly fewer during chewing that in clenching, while that in bruxism subjects, these differences have not been verified. During clenching, a reduction of SCM co-activation referred as temporalis anterior muscle was proven, beyond the reduction of masseter muscle with an increase of temporalis anterior muscle activation has been observed in bruxism subjects. Comparing the values of SCM activation on jaw movements with its maximal isometric contractions, has been verified a significant reduction of muscular activity in right side on bruxism subjects. The results of this research, under those experimental conditions, have allowed concluding that the sternocleidomastoid coactivation during the jaw movements was verified in humans and that this seems to suffer influences from muscular alterations caused by bruxism. Thus, it is perceivable the necessity of accomplishment of more studies about this subject
Doutorado
Anatomia
Doutor em Biologia Buco-Dental
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Alkhaiat, Reem, e Zahra Jaber. "Maximal voluntary occlusal bite force in young adult men -a pilot study". Thesis, Umeå universitet, Institutionen för odontologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-178782.
Testo completoAbstract (sommario):
Background: Maximal voluntary occlusal bite force (MVOBF) is the maximal force applied by the jaw muscles in dental occlusion. MVOBF is one parameter for functional capacity of the jaw system. Aim: To evaluate MVOBF in different positions in the bite and to evaluate possible intra-individual differences between sessions. Methods: MVOBF was measured with an electronic bite force device, with transducers sensitive to force, in 20 healthy men (mean 24.5 years). Eligibility of participants was full dental occlusion, Angle Class I relation, no diagnosis according to Diagnostic criteria for temporomandibular disorders. The test included three repeated measurements on each site: first molar right, first molar left and central incisor, in random order, with test-retest study design. Unpaired T-test was used to test the MVOBF in different positions in the bite and paired T-test for possible intra-individual differences between sessions. A post hoc test for repeated measure one-way ANOVA was added. Results: MVOBF in different positions in the bite was lower in the incisor area compared with the molar region (P<0.0001), but similar between right and left molar side (P=0.48 and P= 0.96, respectively). No intra-individual differences between sessions (molar right P= 0.40; molar left P= 0.81; incisor area P= 0.66). The intra-individual variability for repeated measurements showed variability for incisor area (P= 0.007), but not for molar right and left region (P=0.95 and P=0.49, respectively). Conclusion: The results may provide reference values for MVOBF in young adult men, to be compared with men with pain or dysfunction in the jaw system.
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Peron, Priscila Ferrari. "Possíveis efeitos do aparelho propulsor mandibular sobre o crescimento da mandíbula e tipos de fibras nos músculos mastigatórios". Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/42/42134/tde-15062009-160943/.
Testo completoAbstract (sommario):
Este estudo teve como objetivos avaliar os possíveis efeitos da utilização do aparelho propulsor mandibular removível (APM), sobre o crescimento da mandíbula e tipos de fibras nos músculos masseter superficial, pterigóideo lateral e digástrico em ratas. Vinte e sete ratas isogênicas (Fisher 344) foram divididas em três grupos randomizados: dois controles e um experimental, que utilizou o APM removível por 40 dias não consecutivos. Foram feitas reações histoquímicas para avaliar a distribuição dos tipos de fibras nos músculos mastigatórios. A mandíbula de cada animal foi dissecada e foram realizadas medições lineares da mesma. Não houve diferença estatisticamente significante entre os grupos quanto ao crescimento mandibular, e apenas masseter superficial anterior teve alterações, com aumento no número de fibras rápidas (tipo IIB). Em ratos, este modelo de APM, não estimulou aumento de crescimento mandibular e, somente o músculo masseter superficial sofreu alterações significativas quanto à distribuição dos tipos de fibras.The aim of this study was to evaluate the possibles effects of removeble mandibular propulsive appliance (MPA) on mandibular growth and fiber types of superficial masseter, lateral pyterigoid and digastric muscles. Twenty seven isogenics rats (Fisher 344) were divided into three groups: two controls and one experimental that used the MPA during 40 days. Histochemical analyses was used to evaluate fiber type of masticatory muscles. The jaw of each animal was dissected and measurment was done. There was no signifcant difference on mandibular growth between the groups. Only the anterior portion of superficial masseter had an incresead of rapids fibers (IIB type). These results suggest that this MPA on a rat model, is not efficient to produce any alterations on mandibular growth and just on superficial masseter had significant alterations on muscles fibers types.
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Johansson, Anders. "Context dependent adaptation of biting behavior in human". Doctoral thesis, Umeå universitet, Fysiologi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-91664.
Testo completoAbstract (sommario):
The focus of this thesis was to study an action that humans perform regularly, namely, to hold a morsel between the teeth and split it into smaller pieces. Three different issues related to this biting behavior were addressed: (1) the effect of reduced periodontal tissues on food holding and splitting behavior; (2) the behavioral consequences of performing different bite tasks with different functional requirements, i.e., to split a peanut half resting on a piece of chocolate or to split both the peanut and the chocolate; and (3) the reflex modulations resulting from such a change in the intended bite action. The main conclusions from the experimental studies were the following: First, periodontitis, an inflammatory disease that destroys the periodontal ligaments and the embedded periodontal mechanoreceptors, causes significant impairments in the masticatory ability: the manipulative bite forces when holding a morsel are elevated compared to a matched control population and the bite force development prior to food split is altered. These changes are likely due to a combination of reduced sensory information from the damaged ligaments and to changes in the bite strategy secondary to the unstable oral situation. Second, people exploit the anatomy of jaw-closing muscles to regulate the amount of bite force that dissipates following a sudden unloading of the jaw. Such control is necessary because without mechanisms that quickly halt jaw-closing movements after sudden unloading, the impact forces when the teeth collide could otherwise damage both the teeth and related soft tissues. Splitting a piece of chocolate, for instance, regularly requires >100N of bite force and the jaws collide within 5 ms of a split. On the other hand, when biting through heterogeneous food, the bite force needs to be kept high until the whole morsel is split. The required regulation is achieved by differentially engaging parts of the masseter muscles along the anteroposterior axis of the jaw to exploit differences between muscle portions in their bite force generating capacity and muscle shortening velocity. Finally, the reflex evoked by suddenly unloading the jaw—apparent only after the initial bite force dissipation—is modulated according to the bite intention. That is, when the intention is to bite through food items with multiple layers, the reflex response in the jaw opening muscles following a split is small, thus minimizing the bite force reduction. In contrast, when the intention is to rapidly decrease the bite force once a split has occurred, the reflex response is high. This pattern of reflex modulation is functionally beneficial when biting through heterogeneous food in a smooth manner. The presented studies show the significance of integrating cognitive, physiological and anatomical aspects when attempting to understand human masticatory control.
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Cai, Bonnie Bao Yan. "Sex-related differences in the suppressive effects of peripheral morphine but not GABA on reflex jaw muscle activity evoked by glutamate application to the TMJ region in rats". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ58880.pdf.
Testo completo
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Spagnol, Guilherme. "Avaliação eletromiografica, força de mordida e mobilidade mandibular em indivíduos com fraturas de terço médio e superior da face". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/58/58136/tde-18022016-163507/.
Testo completoAbstract (sommario):
O trauma de face pode ser considerado um problema de saúde pública, principalmente pelo elevado número de indivíduos envolvidos em acidentes, que acabam fraturando os ossos da face. Este estudo avaliou força de mordida, atividade eletromiográfica (EMG) e mobilidade mandibular em pacientes submetidos à cirurgia para tratamento de fraturas de face que necessitaram de acesso cirúrgico tipo coronal. A amostra foi constituída por 10 indivíduos distribuídos em dois grupos distintos: Grupo 1 fraturas de face tratadas cirurgicamente com acesso coronal (n=6); e Grupo 2 fraturas de face tratadas cirurgicamente com acesso coronal com extensão pré-auricular (n=4) e um Grupo Controle demonstrativo composto de pessoas saudáveis pareados em idade e medidas antropométricas com os grupos. Foi avaliada a força de mordida molar máxima por meio de dinamômetro digital; atividade eletromiográfica do músculo masseter direito (MD), masseter esquerdo (ME), temporal direito (TD), temporal esquerdo (TE) por meio do eletromiógrafo MyoSystem-Br1; e mobilidade mandibular utilizando o paquímetro digital. Os períodos avaliados após tratamento cirúrgico do trauma de face foram de 1, 2, 3 e 6 meses. Os dados eletromiográficos, força de mordida e mobilidade mandibular foram tabulados e submetidos à análise estatística (SPSS 21.0) e foi utilizado o teste de medidas repetidas com nível de significância de 5% e intervalo de confiança de 95%. Foi encontrada diferença estatística significante para atividade EMG na lateralidade esquerda para o músculo TD (p=0,02) e contração voluntária máxima para o músculo MD (p=0,04) e músculo TD (p=0,04); na força de mordida molar máxima direita (p=0,00) e esquerda (p=0,01) ao longo do tempo de 1, 2, 3 e 6 meses, após o acesso coronal com extensão. Houve diferença estatística significante ao longo do tempo de 1, 2, 3 e 6 meses, após o acesso coronal para atividade EMG em repouso para o músculo ME (p=0,00), lateralidade esquerda para o músculo TD (p=0,04), contração voluntária máxima para os músculos: MD (p=0,05), ME (p=0,00), TE (p=0,01) e na força de mordida molar máxima esquerda (p=0,01). Os autores concluíram que após a fixação interna estável das fraturas utilizando acesso cirúrgico coronal, os indivíduos recuperaram a atividade eletromiográfica mastigatória, aumentaram a força de mordida molar máxima e aumentaram a mobilidade mandibular, ao longo do tempo avaliado.The facial trauma can be considered a public health problem, particularly the large number of individuals involved in accidents, exhibit face and skull fractures. Studies assessing skeletal muscle behavior after surgical treatment of facial fractures and its functional consequences in the stomatognathic system are of great value to clarify suffered changes and their evolution, and thus can indicate an individualized treatment method benefiting individuals who suffered injure of face. This study aimed to evaluate bite force, electromyographic activity and jaw mobility in patients undergoing surgery for facial fractures that required surgical coronal flap. Ten individuals with fractures of facial bone participate this study divided into two distinct groups: Group 1 complex fractures of face surgically treated by coronal flap (n = 6) and Group 2 - complex fractures of face surgically treated by coronal flap with preauricular approach (n = 4). It was evaluated maximum molar bite force through digital dynamometer; electromyographic activity of the masseter right masseter (RM), left masseter (LM), right temporal (RT), left temporal (RT) muscles, through Myosystem-Br1 and mandibular mobility electromyography using digital pachymeter. During postoperative follow-up, bite force, mandible mobility, and electromyographic analysis of the masticatory muscles were evaluated 1, 2, 3 and 6 months and were tabulated and submitted to statistical analysis (SPSS 21.0) and was used the test repeated measurements with 5% significance level and 95% confidence interval. It found statistically significant differences for EMG activity in the left laterality for RT muscle (p = 0.02) and maximal voluntary contraction of the muscle RM (p = 0.04) and muscle RT (p = 0.04); the right (p = 0.00) and left (p = 0.01) maximum molar bite force, over the time of 1, 2, 3 and 6 months, after coronal access with extension. There was no statistically significant difference over time of 1, 2, 3 and 6 months after coronal access to EMG activity at rest for LM muscle (p = 0.00), left laterality for RT muscle (p = 0.04), maximal voluntary contraction of the muscles: RM (p = 0.05), LM (p = 0.00) , LT (p = 0.01) and left maximum molar bite force (p = 0.01). The authors concluded that the stable internal fixation with coronal surgical approach regained masticatory electromyographic activity, increased the maximum molar bite force and increased mandibular mobility of individuals affected by facial fractures medium and upper third, over time.
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Athanassiadis, Tuija. "Neural circuits engaged in mastication and orofacial nociception". Doctoral thesis, Umeå : Department of Integrative Medical Biology, Umeå university, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-26342.
Testo completo
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Pasinato, Fernanda. "INFLUÊNCIA DA DOR MUSCULAR EXPERIMENTAL SOBRE A FUNÇÃO MASTIGATÓRIA: ANÁLISE CINEMÁTICA E ELETROMIOGRÁFICA". Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/3448.
Testo completoAbstract (sommario):
This thesis aimed to investigate the effects of experimentally induced jaw-muscle pain on the movements and electromyographic activity of jaw and head-neck during chewing in healthy subjects. Kinematic variables related were analyzed: (1) the masticatory sequence (duration, number of cycles masticatory and frequency); (2) the chewing cycle: time of opening, closing and occlusal phase; maximum range of motion and vertical, medial-lateral, anteroposterior and three-dimensional speed of jaw during the phases of opening and closing; maximum amplitude of displacement and head-neck three-dimensional speed during the phases of opening and closing jaw; maximum variation of the cervical flexion-extension angle while chewing; relationship between jaw and head-neck three-dimensional movement. The electromyography variables of the masticatory cycle analyzed were: inactive and active time of the masseter muscles in the side of work and balancing; muscle activation amplitude (MAA) of the masseter and ECM muscles, during active and inactive periods; activation symmetry of the masseter muscles and ECM; coactivation and correlation between masseter MAA and the ECM side of balancing work, during the active period. The study included 28 male volunteers, mean age of 20.6 years. Kinematic data were obtained from Qualisys System and electromyographic data via wireless sensors Delsys. Records were conducted during unilateral chewing wine gum before and after monosodium glutamate solution injections (pain-inducing substance) and normal saline (control). The order and the side of the applications were randomized and separated by a minimum of 45 min. The records before and after experimental procedures were analyzed by t test and Wilcoxon test for dependent variables and the Spearman correlation coefficient was used to analyze the relationship between mandibular and head-neck variables. As a result, it was observed that pain incited reduction on range of mid-lateral movement during the closing jaw, on vertical and three-dimensional speed during the opening and mid-lateral speed during the opening and closing of the masticatory cycle, reduction on MAA masseter muscle side job during the active period prescribed and increased activation symmetry between the masseter muscles on the side of balancing work and during the chewing cycle. However, no effect of pain was observed on the kinematic and electromyographic head-neck variables or on the movement relations and MAA or coactivation between the mandibular and head-neck systems. Moderate effect sizes were observed for results of the kinematic variables of mid-lateral amplitude and mid-lateral/vertical mandibular speed, suggesting that these may have clinical relevance in the evaluation of mastication in the presence of acute pain. Small effect sizes were observed in all results of electromyographic variables, limiting generalizability of the results to the population of patients with TMD. In conclusion, in the presence of acute pain of the stomatognathic system adaptations involve mainly local mechanisms, influencing only kinematic parameters and mandibular electromyographic without compensation on the movement and head-neck electromyographic activity.Esta tese teve como objetivo investigar os efeitos da dor induzida experimentalmente no músculo masseter sobre os movimentos e a atividade eletromiográfica crânio-cervical e mandibular durante a mastigação em indivíduos saudáveis. Foram analisadas variáveis cinemáticas relacionadas: (1) à sequência mastigatória (duração, número de ciclos e frequência mastigatória); (2) ao ciclo mastigatório: duração das fases de abertura, fechamento e fase oclusal; amplitude máxima de movimento e velocidade vertical, médio-lateral, anteroposterior e tridimensional da mandíbula durante as fases de abertura e fechamento; amplitude máxima de deslocamento e velocidade tridimensional crânio-cervical durante as fases de abertura e fechamento mandibular; máxima variação do ângulo de flexo-extensão cervical durante a mastigação; relação entre os movimentos mandibulares e crânio-cervicais tridimensionais. As variáveis eletromiográficas analisadas, durante o ciclo mastigatório, foram: duração do tempo inativo e ativo dos músculos masseteres dos lados de trabalho e balanceio; amplitude de ativação muscular (AAM) dos músculos masseter e esternocleidomastóideo (ECM), durante os períodos ativo e inativo; simetria de ativação dos músculos masseter e ECM; coativação e correlação entre a AAM do masseter e ECM dos lados de trabalho e balanceio, durante o período ativo. Participaram do estudo 28 voluntários do sexo masculino, com média de idade de 20,6 anos. Os dados cinemáticos foram obtidos através do Sistema Qualisys e os dados eletromiográficos por meio de sensores sem fio e eletromiógrafo Delsys. Foram realizados registros em mastigação unilateral de uma bala de goma de consistência firme, antes e depois de injeções de solução de glutamato monossódico (substância indutora de dor) e de solução salina isotônica (controle). A ordem e o lado das aplicações foram randomizados e separados por um intervalo mínimo de 45 minutos. Os dados pré e pós procedimentos experimentais foram analisados pelos testes t e Wilcoxon para variáveis dependentes e o coeficiente de correlação de Spearmann foi utilizado para a análise da relação entre variáveis mandibulares e crânio-cervicais. Como resultados, observou-se que a dor ocasionou redução da amplitude de deslocamento médio-lateral durante o fechamento mandibular; redução das velocidades vertical e tridimensional durante a abertura e velocidade médio-lateral durante a abertura e fechamento do ciclo mastigatório; redução da AAM do músculo masseter do lado de trabalho durante o período ativo e aumento da simetria de ativação entre os músculos masseteres dos lados de trabalho e balanceio durante o ciclo mastigatório. Entretanto, nenhum efeito da dor foi observado sobre as variáveis cinemáticas e eletromiográficas crânio-cervicais ou sobre as relações do movimento, AAM ou coativação entre os sistemas mandibular e crânio-cervical. Tamanhos de efeito moderados foram observados para os resultados das variáveis cinemáticas de amplitude e velocidade mandibular médio-lateral e vertical, sugerindo que estas podem ter relevância clínica na avaliação da mastigação na presença de dor aguda. Tamanhos de efeito pequenos foram observados em todos os resultados das variáveis eletromiográficas, limitando sua generalização para indivíduos com DTM. Em conclusão, na presença de dor aguda, as adaptações do sistema estomatognático envolvem principalmente mecanismos locais, influenciando apenas parâmetros cinemáticos e eletromiográficos mandibulares, sem compensações sobre o movimento e atividade eletromiográfica crânio-cervical.
42
Pearce, Sophie (Sophie Lee). "Motor cortical control of human jaw muscles : a thesis submitted for the degree of Doctor of Philosophy in the Department of Physiology, the University of Adelaide, Adelaide, South Australia". 2002. http://web4.library.adelaide.edu.au/theses/09PH/09php3595.pdf.
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Pearce, Sophie (Sophie Lee). "Motor cortical control of human jaw muscles : a thesis submitted for the degree of Doctor of Philosophy in the Department of Physiology, the University of Adelaide, Adelaide, South Australia / by Sophie Pearce". Thesis, 2002. http://hdl.handle.net/2440/21892.
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Shea, Joseph Frederick. "The effect of canine guidance angulation on mandibular movements a thesis submitted in partial fulfillment ... prosthodontics and restorative dentistry, crown and bridge ... /". 1989. http://books.google.com/books?id=dU4_AAAAMAAJ.
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Nelson, Stanley J. "Masticatory dysfunction index design and initial clinical evaluation : a thesis submitted in partial fulfillment ... restorative occlusion /". 1986. http://books.google.com/books?id=JW89AAAAMAAJ.
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46
Mutirangura, Wantanee. "Computer-analysis of the cross-correlation of the bilateral jaw elevator activity during controlled submaximal clenching a thesis submitted in partial fulfillment ... restorative dentistry, occlusion /". 1988. http://books.google.com/books?id=H3s9AAAAMAAJ.
Testo completo
47
Sowman, Paul Fredrick. "The contribution of periodontal mechanoreceptors to physiological tremor in the human jaw". 2007. http://hdl.handle.net/2440/45672.
Testo completoAbstract (sommario):
The human jaw, like all other articulated body parts, exhibits small oscillatory movements during isometric holding tasks. These movements, known as physiological tremor, arise as a consequence of the interaction of various factors. One of these factors is reflex feedback from peripheral receptors. In the human jaw, receptors that innervate the periodontium are able to transduce minute changes in force. This thesis examines the contribution of these periodontal mechanoreceptors (PMRs) to the genesis of physiological tremor of the human jaw. By using frequency domain analysis of time series recorded during isometric biting tasks, the character of physiological jaw tremor can be revealed. Physiological jaw tremor was observed in force recorded from between the teeth as well as from electromyograms recorded from the principal muscles of mastication. These recordings have shown us that jaw physiological tremor consists of a frequency invariant component between 6 and 10Hz. This frequency remains unaltered under various load conditions where the mechanical resonance of the jaw would be expected to vary greatly (Chapter 2). Such findings indicate a ‘neurogenic’ origin for this tremor. A possible candidate for this neurogenic component of physiological tremor in the jaw is the reflex feedback arising from the PMRs. Using local anaesthetisation, it has been shown in this thesis, that by blocking outflow from the PMRs, the amplitude of neurogenic physiological jaw tremor can be reduced dramatically. This procedure caused a dramatic reduction in not only the mechanical recordings of tremor but also in the coupling between masseteric muscles bilaterally (Chapter 3) and between single motor units recorded from within a homonymous muscle (Chapter 4). The obvious mechanism by which periodontal mechanoreceptor anaesthetisation could reduce the amplitude of physiological tremor in the jaw would be by reducing the amplitude of the oscillatory input to the motoneurones driving the tremor. This interpretation remains controversial however as physiological tremor in the jaw can be observed at force levels above which the PMRs are supposedly saturated in their response. In light of this knowledge, the saturating characteristics of these receptors in terms of reflex output were examined. To do this, a novel stimulation paradigm was devised whereby the incisal teeth were mechanically stimulated with identical stimulus waveforms superimposed upon increasing tooth preloads. This necessitated the use of a frequency response method to quantify the reflexes. An optimal frequency for stimulation was identified and used to confirm that the hyperbolic saturating response of PMRs observed previously, translated to a similar phenomenon in masticatory reflexes (Chapter 5). These data reinforced the idea that physiological tremor in the jaw was not just a consequence of rhythmic reflex input from PMRs, as the dynamic reflex response uncoupled from the input as the receptor-mediated reflex response saturated. An alternative hypothesis was then developed that suggested the effect of PMR suppression in physiological tremor was via tonic rather than rhythmic effects on the masseteric motoneurone pool. By utilising a novel contraction strategy to manipulate the mean firing rate of the motor neuron pool at a given level of force production, data contained in Chapter 6 shows that population motor unit firing statistics influence the expression of physiological tremor, and such manipulations mimic, to an extent, the changes in firing statistics and tremor amplitude seen during anaesthetisation of the PMRs. This thesis therefore posits a mechanism whereby periodontal input influences the firing rate of motoneurones in such a way as to promote tremulous activity (Chapter 5). However, as this proposed mechanism did not explain the full extent of tremor suppression seen during PMR anaesthetisation it can therefore only be considered a contributing factor in a multifactor process.http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1297555
Thesis (Ph.D.) -- University of Adelaide, School of Molecular and Biomedical Science, 2007
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Sowman, Paul Fredrick. "The contribution of periodontal mechanoreceptors to physiological tremor in the human jaw". Thesis, 2007. http://hdl.handle.net/2440/45672.
Testo completoAbstract (sommario):
The human jaw, like all other articulated body parts, exhibits small oscillatory movements during isometric holding tasks. These movements, known as physiological tremor, arise as a consequence of the interaction of various factors. One of these factors is reflex feedback from peripheral receptors. In the human jaw, receptors that innervate the periodontium are able to transduce minute changes in force. This thesis examines the contribution of these periodontal mechanoreceptors (PMRs) to the genesis of physiological tremor of the human jaw.
By using frequency domain analysis of time series recorded during isometric biting tasks, the character of physiological jaw tremor can be revealed. Physiological jaw tremor was observed in force recorded from between the teeth as well as from electromyograms recorded from the principal muscles of mastication. These recordings have shown us that jaw physiological tremor consists of a frequency invariant component between 6 and 10Hz. This frequency remains unaltered under various load conditions where the mechanical resonance of the jaw would be expected to vary greatly (Chapter 2). Such findings indicate a ‘neurogenic’ origin for this tremor. A possible candidate for this neurogenic component of physiological tremor in the jaw is the reflex feedback arising from the PMRs.
Using local anaesthetisation, it has been shown in this thesis, that by blocking outflow from the PMRs, the amplitude of neurogenic physiological jaw tremor can be reduced dramatically. This procedure caused a dramatic reduction in not only the mechanical recordings of tremor but also in the coupling between masseteric muscles bilaterally (Chapter 3) and between single motor units recorded from within a homonymous muscle (Chapter 4).
The obvious mechanism by which periodontal mechanoreceptor anaesthetisation could reduce the amplitude of physiological tremor in the jaw would be by reducing the amplitude of the oscillatory input to the motoneurones driving the tremor. This interpretation remains controversial however as physiological tremor in the jaw can be observed at force levels above which the PMRs are supposedly saturated in their response. In light of this knowledge, the saturating characteristics of these receptors in terms of reflex output were examined. To do this, a novel stimulation paradigm was devised whereby the incisal teeth were mechanically stimulated with identical stimulus waveforms superimposed upon increasing tooth preloads. This necessitated the use of a frequency response method to quantify the reflexes. An optimal frequency for stimulation was identified and used to confirm that the hyperbolic saturating response of PMRs observed previously, translated to a similar phenomenon in masticatory reflexes (Chapter 5).
These data reinforced the idea that physiological tremor in the jaw was not just a consequence of rhythmic reflex input from PMRs, as the dynamic reflex response uncoupled from the input as the receptor-mediated reflex response saturated. An alternative hypothesis was then developed that suggested the effect of PMR suppression in physiological tremor was via tonic rather than rhythmic effects on the masseteric motoneurone pool.
By utilising a novel contraction strategy to manipulate the mean firing rate of the motor neuron pool at a given level of force production, data contained in Chapter 6 shows that population motor unit firing statistics influence the expression of physiological tremor, and such manipulations mimic, to an extent, the changes in firing statistics and tremor amplitude seen during anaesthetisation of the PMRs. This thesis therefore posits a mechanism whereby periodontal input influences the firing rate of motoneurones in such a way as to promote tremulous activity (Chapter 5). However, as this proposed mechanism did not explain the full extent of tremor suppression seen during PMR anaesthetisation it can therefore only be considered a contributing factor in a multifactor process.Thesis (Ph.D.) -- University of Adelaide, School of Molecular and Biomedical Science, 2007
49
Liu, YiHsien, e 劉乙諴. "Recruitment of Masticatory Muscles and Sternocleidomastoid Muscle at Different Retrusive-Protrusive Jaw Position in Patients of TMJ Arthritis". Thesis, 2000. http://ndltd.ncl.edu.tw/handle/43727379716274540301.
Testo completoAbstract (sommario):
碩士國立臺灣大學
臨床牙醫學研究所
88
The purpose of this study was to examine the recruitment of masticatory muscles and sternocleidomastoid muscle at different protrusive-retrusive jaw positions under the control of biting forces. Twenty female patients of TMJ arthritis whose overjet and overbite of anterior teeth had found to be changed during the course of treatment were included in this study. Twenty-one normal subjects with similar age, height and weight were selected as control group. A fork-type force transducer was constructed with four bonded strain gauges connected in full bridge, which was then calibrated at different loading positions. It was found that the change of loading positions on the fork end did not lead to statistically significant difference of voltage output (p=0.9998). In the main study, electromyographic(EMG) activities of maximum voluntary clenching were firstly obtained by surface electrodes from both sides of masseter, sternocleidomastoid（SCM）, anterior and posterior temporalis muscles at intercuspal position (ICP) and anterior edge to edge position. Then the subjects were instructed to bite at controlled protrusive-retrusive jaw positions with the force transducer placed in the first molar locations of habitual chewing side. The most retrusive jaw position is defined as ?" position, which then determined protrusive 2 and 4 mm jaw positions. At each jaw positions, biting force levels of 50, 100 and 150N, were conducted with visual analog. Each experimental task consists of 3 seconds continuous biting with 5 repeated trials. The magnitude of force was synchronously recorded with EMG activities of masseter, SCM, anterior and posterior temporalis muscles on both sides. Root mean square of muscle activities was derived for each muscle. The results showed that the arthritic patients revealed lower EMG activities at ICP than the controls whereas no significant difference was found between groups at anterior edge to edge biting position. With GEE model, it was found that muscle activities were positively influenced by bite force magnitude（P＜0.05）in both group. The muscle activities were negatively influenced by protrusive jaw positions only in control group（P＜0.05）, but not significant in patient group. Bite fork position also showed positive influence on ipsilateral muscle activities（P＜0.05）. Besides, muscle recruitment pattern of SCM showed similar tendency as that of masseter muscle during clenching at ICP, while no clear co-activation of masticatory muscles and SCM was found during unilateral bite tasks. Based on these findings, it can be concluded that the most significant factor influenced the muscle activities was the magnitude of bite force；however, masticatory muscles recruitment did not show significant difference at different jaw position in the patient group.
50
Chi, Shu-ying. "Silent period and muscle phasic vibration a thesis submitted in partial fulfillment ... in occlusion ... /". 1985. http://catalog.hathitrust.org/api/volumes/oclc/68788265.html.
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