Biomedical subjects

M Vitti

Publications and source records attributed to M Vitti.

At least 19 recordsLinked to original sources

PubMed2006

Electromyographical analysis of the masseter muscle in dentulous and partially toothless patients with temporomandibular joint disorders.

This study had as objective to analyze with computerized electromyography the masseter muscles bilaterally in twenty individuals with temporomandibular joint dysfunction (DTM), being: the group I consisting of ten individuals with complete dentition and group II constituted by ten individuals with posterior dental absences; comparing nine clinical activities: rest before and after exercises, maximum habitual intercuspation (MIH), right and left laterality, forced centric occlusion, protrusion, bilateral molar bite and chewing. It was utilized the Electromyography K6I-Myotronics, with eight canals and surface silver electrodes. By means of the results analysis, we verified significant differences between the groups (p < 0.01), being group I, presented greater electromyographic activity (32.98 microvolts), than the group II (22.31 microvolts), suggesting that this individuals presented low muscular activity. The interaction between the groups and the clinical activities was significant (p < 0.01), as well as between the groups, clinical activities and muscles (p < 0.05). To clarify which amongst the relative averages the clinical activities were different, calculated the critical value of Tukey, being that rest before and after exercises, MIH, right and left laterality, presented averages with similar distributions, with values below of the values of Tukey, as well as forced centric occlusion, protrusion, bilateral molar bite and chewing presented higher values than Tukey. Based on this research's data, we concluded that the electromyographical analysis of the masseter muscles in Individuals with TMD, dentulous and with dental absence showed that individuals with TMD, dentulous or not, presented elevated muscular activity in rest position and individuals with TMD, dentulous, presented higher electromyographical activity than the individuals with TMD and lacking posterior teeth.

Adult↗

PubMed2006

Electromyographic amplitude variability of chewing cycles in deaf individuals.

This study had the goal of determining if the amplitude of the surface electromyograph signals changes in terms of time of analysis and subjects, deaf or normal listeners, when estimated in a 250 ms of length window, visually determined, considering the most stable signal period from the center of the chewing cycle. In order to do this, groups with control subjects, listeners and deaf individuals, who made use of the Brazilian sign language (LIBRAS), were studied. All participants performed continuous 5 s of chewing for the electromyographic recording of the temporalis and masseter muscles. The normalized RMS values of three chewing cycles were compared between and among groups. The results from the Kruskall-Wallis test did not show any statistically significant differences (p > 0.05) between the normalized RMS values obtained in the three individual chewing cycles, for each of the two completed and evaluated cycles, in both groups studied. The Mann-Whitney test showed that the mean normalized RMS values obtained in the first chewing cycle were higher for the control group when compared to the mean amplitude values of the first chewing cycle of the group of deaf volunteers. It can be concluded that, in these experimental conditions, the RMS values obtained from the select windows of 250 ms length duration, in relatively stable periods of the electromyographic signal of chewing cycles did not suffer any changes in terms of EMG register duration, in both studied groups, but does give evidence of the differences among the groups.

Adolescent↗

PubMed2004

Electromyographic evaluation of masseter and anterior temporalis muscles in patients with temporomandibular disorders following interocclusal appliance treatment.

The purpose of this study is to evaluate the interocclusal appliance efficiency in patients with temporomandibular disorder (TMD), by using computerized electromyographic (EMG) evaluation in the rest position of the mandible. Twenty-two patients (male and female) with TMD symptoms, between 18 and 53 years of age, were examined. EMG evaluations were performed before the treatment and during the 90th, 120th and 150th day of using the interocclusal appliance therapy. In the 90th and 120th day, inserting canine guidance and group function disclusion, respectively, changed interocclusal appliance. The results showed that group function disclusion caused shorter EMG activity in the mandible rest position for the anterior temporalis muscle.

Adolescent↗

PubMed2003

Electromyographic validation of basic exercises for physical conditioning programmes. IV. Analysis of the deltoid muscle (anterior portion) and pectoralis major muscle (clavicular portion) in frontal-lateral cross, dumbbells exercises.

The electromyographic activity of the shoulder muscles deltoid--anterior portion (DA) and pectoralis major--clavicular portion (PMC) was tested on 24 male volunteers using a 2 channel TECA TE4 electromyograph and Hewlett Packard surface electrodes during the execution of four different modalities of frontal-lateral cross, dumbbells exercises. The results showed that all of the tested exercises developed high levels of action potential for both muscles. So, we justify the indication of all of them for physical fitness programmes for DA and PMC. Some suggestions to the use of the tested exercises are presented.

Action Potentials↗

PubMed2003

Electromyographic validation of basic exercises for physical conditioning programmes. V. The comparison of the response in the deltoid muscle (anterior portion) and the pectoralis major muscle (clavicular portion) determined by the frontal-lateral cross, dumbbells and the rowing exercises.

The action potential level for shoulder muscles deltoid-anterior portion (DA) and pectoralis major-clavicular portion (PMC) determined by four different modalities of execution of rowing exercises, each one with two different grips, was recorded. These were compared with the action potential level determined for the same muscles by four different modalities of execution of the frontal-lateral cross, dumbbells exercises. Twenty-four male volunteers were examined using a 2 channel TECA TE4 electromyograph and Hewlett Packard surface electrodes. The statistic analysis showed significant (p < 0.05) superiority for all the frontal-lateral cross, dumbbells exercises in comparison to all rowing exercises for the PMC, for the DA this generalized supremacy was not observed.

Action Potentials↗

PubMed2003

Electromyographic evaluation of the adductor pollicis muscle of elderly patients carriers of removable partial prosthesis when using acrylic devices adapted to the handle of toothbrush.

The aim of this study was to evaluate the muscular activity of the adductor pollicis muscle, by electromyography, when using a device made of acrylic resin adapted to the handle of toothbrush. 10 patients of both sexes from the Clinic of Removable Partial Dentures of the Dental School--USP, with a mean age of 65 years, were selected. Electromyographic records were obtained with patients in clinical conditions of Initial Rest and under conditions of claw apprehension and dental brushing. The mean results obtained, in mV, were: sat men: 2.97 for rest (R); 11.55 for free closure (FC); 35.80 for strained closure (SC); 29.30 for simulated brushing (SB); 55.00 for brushing (B); 26.87 for simulated brushing with the device (SBA); 69.70 for brushing with the device (BA); 3.72 for post exercise rest (PR). Standing: 2.27 for rest (R); 13.92 for free closure (FC); 45.85 for strained closure (SC); 28.40 for simulated brushing (SB); 72.07 for brushing with the device (BA); 1.42 for postexercise rest (PR). Sat women: 9.78 for rest (R); 22.71 for free closure (FC); 41.48 for strained closure (SC); 26.45 for simulated brushing (SB); 52.78 for brushing (B); 17.00 for simulated brushing with the adapter (SBA); 42.38 for brushing with the adapter (BA); 14.40 for postexercise rest (PR). Standing: 5.26 for rest (R); 17.81 for free closure (FC); 46.55 for strained closure (SC); 40.61 for simulated brushing (SB); 61.71 for brushing (B); 26.08 for simulated brushing with the adapter (SBA); 54.06 for brushing with the adapter (BA); 3.46 for postexercise rest (PR). The adductor pollicis muscle showed a higher electromyographic activity, considered statistically similar to each other, in 3 clinical conditions analyzed: brushing (B), brushing with the adapter (BA) and strained closure (SC). The adductor pollicis muscle showed lower electromyographic activity, considered statistically similar, in 5 clinical conditions analyzed: simulated brushing (SB), simulated brushing with the adapter (SBA), free closure (FC), rest (R) and postexercise rest (PR).

Acrylic Resins↗

PubMed2003

EMG analysis of the upper and lower fascicles of the orbicularis oris muscle in deaf individuals.

The aim of this study was to analyze electromyographically the upper and lower fascicles of the orbicularis oris muscle in deaf patients comparing them with clinically normal patients. These patients present several disorders in facial muscles, temporomandibular joints disorders and constantly headache in virtue of not the use of the face expression muscles. This was performed in 30 patients from both sexes with a mean age of 18.5 years, divided into 3 groups of 10 patients each: 1. deaf patients with buccal breathing and incompetent lips; 2. in deaf patients with nasal breathing and competent lips; 3. clinically normal patients, in 7 clinical conditions: at rest with and without labial contact, sucking water, blowing, pursing and reciprocal compression of the lips and the emission of the syllabi "PA". It was observed that in the deaf patients group, both fascicles of the orbiculares oris muscles presented hyperactivity in most of the analyzed movements, mainly in buccal breathing with incompetent lips, and the lower fascicle demonstrated the highest electromyographic activity.

Adolescent↗

PubMed2002

Electromyographic study of the masseter muscle in individuals with Class II malocclusion.

The objective of this work was to study the action of the masseter muscle through electromyography and to analyze the difference of action potential generated by several pre-established jaw movements in individuals with Class II malocclusion. It was studied nine young individuals from both sexes, with ages ranging from 17 to 35, with no history of orthodontic treatment and/or having some kind of alteration in the temporomandibular joint (T.M.J.). In order to collect the electromyographic signs we have used a TECA TE-4 Electromygraph and surface electrodes type Beckman. The data were submitted to nonparametric statistical analysis by Friedman test. The response variables left occlusive contact, free protraction, protraction with occlusive contact, incisor mastication, right molar mastication and forced central occlusion movements showed significant outcomes. Thus we have concluded that as the occlusive balance suffers alterations, the malocclusions become predominant and the masseter muscle undergoes functional and structural modifications.

Action Potentials↗

PubMed2002

Electromyographic validation of the trapezius and serratus anterior muscles in the rowing and frontal-lateral cross, dumbbells exercises.

The trapezius and serratus anterior muscles were studied in four modalities of rowing exercises executed with two grips, middle and closed, in comparison with the four different modalities of frontal-lateral cross, dumbbells exercise. It was used 24 male volunteers, 18 to 25 years old using a 2-channel TECA TE 4 electromyograph and Hewlett Packard surface electrodes. The results showed that TS acted in a higher significant way in all the modalities of rowing than in the supine lateral raise, inclined supine lateral raise and reverse supine lateral raise, dumbbells exercices, and demonstrated no standing frontal-lateral cross, dumbbells. The SI acted more significantly difference among all the execution modalities of rowing and the inclined supine lateral raise, dumbbells exercises than in all the rowing exercises; even though the activity levels do not make us suggest them as an excellent group of exercises for the development of this muscle.

Adolescent↗

PubMed2002

Electromyographic validation of the trapezius and serratus anterior muscles in rowing exercises with closed grip.

Because the lack of specialized textbooks, the select of basic exercises for physical conditioning programmes is based on empirical knowledge. This fact led the authors to propose the study on electromyographic activity of the trapezius (upper portion) (TS) and the serratus anterior (lower portion) (SI) muscles in rowing exercises with closed grip in three different modalities. The tests were carried out with 24 male volunteers, 18 to 25 years old, by using a two-channel TECA TE 4 electromyograph and Hewlett Packard surface electrodes. For exercises execution, a long bar made of light wood was used. TS acted significantly in the three different modalities, that is, upright, sitting and bent over, while SI acted preferentially in upright and sitting rowing exercises, justifying their inclusion as basic exercises in physical conditioning programmes.

Adolescent↗

PubMed2001

Electromyographic validation of the trapezius and serratus anterior muscles in military press exercises with open and middle grip.

Electromyographic activity of the trapezius muscle and serratus anterior muscle was analysed in 4 different modalities of military press exercises, each of them with 2 grips: open and middle. It was analyzed 24 male volunteers using a 2-channel TECA TE 4 electromyograph and Hewlett Packard surface electrodes. The TS and SI muscles acted with high and very high activity in all the modalities of military press exercises. Statistically, they did not show significative difference in the performance of the exercises with open and middle grip, justifying the inclusion of this group of exercises with both grips for the physical conditioning programmes.

Adolescent↗

PubMed1999

EMG activity of the orbicularis oris and mentalis muscles in children with malocclusion, incompetent lips and atypical swallowing--part II.

The EMG activity of the orbicularis oris (upper and lower), and of the mentalis muscles was verified during several movements of the lips, in 18 children ageing from 8 to 12 years, divided into three groups: one with normal occlusion, and two with class II division 1, with atypical swallowing and/or incompetent lips and who had received no orthodontic treatment. In blowing through a straw the muscular activity of the orbicularis oris and the mentalis was significantly greater in the incompetent lips group. The mentalis presented moderate activity in the competent lips group and negligible in normal occlusion. In puffing out of the cheeks, the malocclusion groups developed marked activity of the orbicularis oris and very marked activity of the mentalis, while the normal occlusion presented moderate and negligible activities, respectively. In pursing of the lips, only the incompetent lips group presented a very marked activity of the lower segment. The compression of the lips against the teeth revealed a marked activity of the upper segment of the orbicularis oris in the groups of malocclusion and the mentalis presented greater activity in the competent lips group. The reciprocal compression of the lips presented a hyperactivity of the three muscles.

Action Potentials↗

PubMed1999

Electromyographic behaviour of the gastrocnemius muscle during knee extension and flexion performed on the leg press.

The gastrocnemius was analysed in 10 male volunteers during knee flexion and extension with the foot in normal, plantar flexion and dorsal flexion positions. Hewlett-Packard surface electrodes, an electromyographic signal amplifier, a computer equipped with an A/D conversion plaque (Model CAD 10/26), a software specially designed to record and analyse the signals, a horizontal leg press, and electrogoniometers were used. The gastrocnemius muscle showed strong potentials at the end of knee extension and beginning of knee flexion. The muscle presented a similar activity both in the upper and lower platforms. As to bilateral action, the right gastrocnemius presented stronger potentials on the upper platforms, whereas the potentials were bilaterally similar on the lower platforms. As for foot position, the gastrocnemius presented strong potentials when the foot was in plantar flexion. The remaining positions had no effect on the work of the muscle.

Adult↗

PubMed1998

EMG activity of the orbicularis oris and mentalis muscles in children with malocclusion, incompetent lips and atypical swallowing--part I.

The function and the level of activity of the orbicularis oris (upper and lower), and of the mentalis muscles were verified electromyographically in resting position and in several movements and carried out in 18 children aged 8-12 years, divided into three groups: one with normal occlusion, and two with Class II division 1, with atypical swallowing and/or incompetent lips, who had received no orthodontic treatment. It was observed that, in a resting position with the lips separated, there was no activity in any of the muscles. When there was a contact of the lips, action potentials were recorded in the muscles studied, in those individuals with incompetent lips. In the movements of sucking either through a straw or a pacifier and the thumb, there were no differences among the groups. The incompetent lips group presented very marked muscle activity of the lower orbicularis oris and mentalis in the movement of sucking a lollipop. In deglutition of saliva, the orbicularis oris presented slight activity, and the mentalis, moderate. In deglutition of water, the mentalis presented very marked activity, whereas, the upper and lower orbicularis oris presented moderate and marked activities, respectively.

Action Potentials↗

PubMed1998

Electromyographic evaluation of the rectus femoris muscle during exercises performed on the leg press.

The rectus femoris was analysed in 10 volunteers during knee flexion and extension with the feet in normal, plantar flexion and dorsal flexion positions. Hewlett-Packard surface electrodes, an electromyographic signal amplifier, a computer equipped with an A/D conversion plaque (Model CAD 10/26), software specially designed to record and analyse the signals, Horizontal Leg Press, and electrogoniometers were used. The rectus femoris muscle showed strong potentials at the beginning of knee extension. In the simultaneous bending of the knee and hip the activity was strong toward the end of the movement. The rectus femoris showed a similar activity both in the upper and lower platforms. As for foot positions, the rectus femoris showed the smallest potentials with the foot in plantar flexion and the largest ones with the foot in dorsal flexion.

Adult↗

PubMed1996

Electromyographic validation of basic exercises for physical conditioning programmes. II. Analysis of the deltoid muscle (anterior portion) and pectoralis major muscle (clavicular portion) in rowing exercises with closed grip.

The electromyographic activity of the shoulder muscles deltoid-anterior portion (DA) and pectoralis major-clavicular portion (PMC) was tested on 24 male volunteers using a 2 channel TECA TE4 electromyograph and Hewlett Packard surface electrodes during the execution of three different modalities of rowing exercises with closed grip. All rowing exercises were inefficient to determine action potential levels in the PMC but two of them were extremely efficient to the DA: the upright rowing exercise and the sitting rowing exercise. Some suggestions to the use of the tested exercises are presented by the authors.

Action Potentials↗

PubMed1996

Electromyographic validation of basic exercises for physical conditioning programmes. III. Influence of the grip in the capacity of the rowing exercises in determining action potential levels for the deltoid and the pectoralis major muscle.

The electromyographic activity of the shoulder muscles Deltoid--anterior portion (DA) and Pectoralis major--clavicular portion (PMC) was tested on 24 male volunteers using a 2 channel TECA TE4 electromyograph and Hewlett Packard surface electrodes during the execution of three different modalities of rowing exercises comparing middle grip with closed grip. Statistical comparisons showed that in both PMC and DA closed grip determined muscular solicitation higher than middlegrip excepting sitting rowing. The authors present some suggestions to the use of the tested exercises.

Action Potentials↗

PubMed1994

Recombinant soluble human thrombomodulin: a randomized, blinded assessment of prevention of venous thrombosis and effects on hemostatic parameters in a rat model.

UNLABELLED: Thrombomodulin is an endothelial surface receptor that binds thrombin and accelerates the activation of protein C. We compared the effects of a recombinant thrombomodulin analog (TME), recombinant hirudin (r-HIR), heparin sodium (HEP), and normal saline (Control) on thrombus formation, activated partial thromboplastin time (APTT), thrombin time (TT), platelet aggregation and tail transection bleeding time (BT) in a rat model of vena cava thrombosis. RESULTS: TME, r-HIR and HEP prevented venous thrombosis in this model in a dose-dependent manner. At the dose required to reduce vena cava thrombosis by 50% (ED50), TME did not prolong the APTT or TT as did HEP and r-HIR. Platelet aggregation in response to thrombin was not effected by TME but was inhibited by both r-HIR and HEP. BT did not differentiate the agents tested. CONCLUSION: TME inhibited venous thrombosis in a rat vena cava model with less effect on hemostatic variables than HEP or r-HIR.

Animals↗