Orbicularis Oris Muscle Activity Research Articles

Electromyographic Evaluation of Superior Orbicularis Oris Muscle Activity in Patients With Complete Cleft Lip and Cleft Palate Before and After Vestibuloplasty Using Carbon Dioxide Laser Therapy.

Introduction: Cleft lip and cleft palate are the most typical congenital craniofacial anomalies. Post-surgical scars in cleft lip patients can cause shallow upper labial sulcus and reduced upper lip length. The aim of the present study was to evaluate the impact of CO2 laser vestibuloplasty on the electromyographical (EMG) activity of patients' superior orbicularis oris muscle, depth of labial sulcus, and upper lip length, and their satisfaction with the procedure and its results. The CO2 laser is an effective vestibuloplasty procedure, is safe and highly acceptable for patients, and has little effect on muscle contraction. Methods: A total of 15 cleft lip and cleft palate patients participated in this study. Vestibuloplasty was performed using carbon dioxide laser therapy in one session in such a way that EMG activity in the upper lip muscle, depth of labial sulcus, and upper lip length were measured two times: before (T0) and twenty days after surgery (T1). Patients' satisfaction surveys were also recorded using a patient questionnaire at T1. Results: The mean values for vestibular depth at T0 and T1 were 2.00±1.71 and 4.52±1.43, respectively. The mean values for upper lip length at T0 and T1 were 6.90±2.32 and 8.00±2.40, respectively, suggesting a significant change in vestibular depth and upper lip length. The vestibular depth and upper lip length significantly increased at T1. The EMG recording of the upper lip muscle experienced a moderate decrease after laser treatment, both at rest and at maximum lip protrusion. Moreover, patients' satisfaction with the surgical procedure was 82% positive. Conclusion: Using the CO2 laser increased the vestibular depth and upper lip length successfully and made small changes in the EMG activity of the superior orbicularis oris.

Superior Orbicularis Oris Muscle Activity in Children Surgically Treated for Bilateral Complete Cleft Lip and Palate.

The aim of this cross-sectional study was to evaluate the electromyographic activity of the superior orbicularis oris muscle both in children surgically treated for bilateral complete cleft lip and palate (BCCLP) as well as in subjects without BCCLP. The study comprised 77 children aged 6.6 to 12.5 years. All the patients with clefts had previously undergone lip and palate surgery. The upper lip electromyographic (EMG) assessments were made with a DAB-Bluetooth device (Zebris Medical GmbH, Germany) at rest, while swallowing saliva, protruding lips and compressing lips. EMG measurements were also made when the subjects produced phonemes /p/, /b/, and /m/ with the vowel /a/. The Mann-Whitney U test was applied to statistically analyze the EMG values. Significantly higher median upper lip EMG activity under working conditions such as swallowing saliva, lip compression, and production of the phoneme /p/ with the vowel /a/ was observed in patients with BCCLP compared to those without a cleft. The results of the study showed that the upper lip muscle activity increases in children with BCCLP when swallowing saliva, compressing lips and during some speech movement tasks. This may be important in the aspect of the effect of surgical lip repair on the craniofacial growth.

Orofacial myofunctional changes and electromyographic activity of the orbicularis oris muscle in trombonists

ABSTRACT Objective: to analyze whether trombonists present orofacial myofunctional changes and compare the electrical activity of the orbicularis oris muscle before and after playing their instrument. Methods: an observational, descriptive, and cross-sectional study. The sample consisted of 20 university trombonists. Data collection involved three steps: application of a questionnaire investigating some peculiarities of trombonists (Orofacial Myofunctional Evaluation with Expanded Scores - OMES-E), and electromyographic analysis of the orbicularis oris muscle before and after performing a piece with the trombone. The mean, standard deviation, frequency, and percentage were calculated, and the paired Student’s t test was used to compare the means of the electromyographic records before and after playing the trombone, at a 5% significance. Results: seventy per cent of trombonists reported some symptom of orofacial myofunctional alteration, namely, muscle compensations, tension, and pain. The myofunctional evaluation showed a mild change in cheek volume (90%) and labial commissure asymmetry (60%). The electrical activity of the lower orbicularis oris muscle decreased significantly after the trombone practice (p = 0.04), while that of the superior orbicularis oris muscle remained unchanged. Conclusion:trombonists show clinical and self-reported oromyofunctional changes as well as decreased electrical activity of the lower orbicularis oris muscle, after playing the trombone.

Iatrogenic injury and regeneration of the facial nerve after parotid gland tumour surgery: a pilot study with clinical and neurophysiological assessment

Introduction. Benign tumour surgery of the parotid gland may cause iatrogenic injury of the facial nerve, with results of postoperative treatment depending on the type of injury. The study aimed to clarify the mechanism of facial nerve injury after benign tumour surgery of parotid gland. Materials and Methods. The effectiveness was verified preoperatively and 1, 3, 6 and 17 months postoperatively. House-Brackmann scales, electroneurography, blink reflex study and needle electromyography were performed. Pharmacological treatment (Galantamine, Cocarboxylase, Dexamethasone, Triamcinolone) and supervised physiotherapeutic procedures (Facial-Oral-Tract-Therapy, Proprioceptive neuromuscular facilitation) were applied for six months. Results. Tumour removal led to the total paralysis of the left facial nerve, IV, III and III House-Brackmann grades were ascertained at the subsequent 3rd–5th periods of observation. In postoperative studies, electroneurography results showed full functional recovery of the frontal branch and incomplete regeneration in the marginal mandibular branch. Blink reflex examination showed proper parameters of evoked potentials only during preoperative and the last observation period. Residual voluntary activity of the frontal muscle and weak voluntary activity of orbicularis oris muscle were recorded in the needle electromyography examination. Contracture of mimic muscles at rest and improvement of their voluntary activity on the left side was observed six months after surgery compared to the early period of observation. Conclusion. Consecutive studies showed the predominant axonal type of injury in the marginal mandibular branch and neuropraxia effect of the facial nerve, allowing the creation of a rehabilitation programme optimal for the functional recovery of the nerve.

Assessment of hypoxic lip training for lip incompetence by electromyographic analysis of the orbicularis oris muscle.

The aims of this study were to determine the difference in electromyography (EMG) of the orbicularis oris muscles between subjects with lip incompetence and lip competence and to elucidate the effectiveness of hypoxic lip training with EMG. Twenty-five subjects (14 men, 11 women; mean age, 24.5±2.6years) were divided into 2 groups by sealed lip ratio: 13 subjects with lip incompetence (LI) and 12 subjects with lip competence (LC). Integral values of EMG for the orbicularis oris muscle during lip closing were estimated (baseline, T1). Then the subjects in the LI group performed the hypoxic lip training every day for 4weeks. The EMG recordings were repeated during the training (T2), immediately after the training (T3), 4weeks after the training (T4), and 8weeks after the training (T5). In the LI group, the EMG values during lip closing were significantly higher than those of the LC group, and the values of EMG during lip closing at T3 were significantly lower than those at T1. In the posttraining period, the values of EMG at T4 and T5 were significantly lower than those at T1. The results suggested that subjects with lip incompetence need greater orbicularis oris muscle activity to keep their lips closed. The suggested standardized lip training could be used as a training method for patients with lip incompetence.

Effect of Expiratory Resistive Loading in Expiratory Muscle Strength Training on Orbicularis Oris Muscle Activity

[Purpose] The purpose of this study was to elucidate the effect of expiratory resistive loading on orbicularis oris muscle activity. [Subjects] Subjects were 23 healthy individuals (11 males, mean age 25.5±4.3 years; 12 females, mean age 25.0±3.0 years). [Methods] Surface electromyography was performed to measure the activity of the orbicularis oris muscle during maximum lip closure and resistive loading at different expiratory pressures. Measurement was performed at 10%, 30%, 50%, and 100% of maximum expiratory pressure (MEP) for all subjects. The t-test was used to compare muscle activity between maximum lip closure and 100% MEP, and analysis of variance followed by multiple comparisons was used to compare the muscle activities observed at different expiratory pressures. [Results] No significant difference in muscle activity was observed between maximum lip closure and 100% MEP. Analysis of variance with multiple comparisons revealed significant differences among the different expiratory pressures. [Conclusion] Orbicularis oris muscle activity increased with increasing expiratory resistive loading.

Effect of vertical and horizontal dimensions of button-pull exercise device on orbicularis oris muscle activity and peak force during button-pull exercise for lip closure

Effect of vertical and horizontal dimensions of button-pull exercise device on orbicularis oris muscle activity and peak force during button-pull exercise for lip closure

The effects of food consistency on jaw movement and posterior temporalis and inferior orbicularis oris muscle activities during chewing in children

The possible effects of food consistency on the number of chews and the lapse of time in a chewing sequence, the jaw-movement pattern and velocity, and jaw and lip muscle activity during chewing were investigated. Fifteen healthy children with good occlusion were selected. First, each subject freely chewed hard (HJ) and soft (SJ) types of jelly without specifying the chewing side. The number of chews and elapsed time in a masticatory sequence (from the start of chewing to the completion of the final swallow) were measured. Second, the subjects performed right- and left-sided chewing of the same food. The electromyograms (EMG) of posterior temporalis (PT) and inferior orbicularis oris (OI) muscles on the right and left sides and associated jaw movement records were sampled. The HJ was chewed more times and with a longer time until finally swallowed ( p ⩽ 0.0007) than the SJ. The HJ chewing also showed broader masticatory loops ( p ⩽ 0.0199) in the frontal view and higher peak activities ( p ⩽ 0.0007) for the PT muscle. The closing phase was longer when chewing the HJ than SJ, but the opening and intercuspal phases remained stable. More lateral excursion of the jaw was seen when chewing the HJ, but the jaw-movement trajectories in the sagittal and vertical directions were not affected by the change in consistency of the food. The jaw-closing velocities for the HJ chews were significantly slower ( p ⩽ 0.0351) than those for the SJ chews in three directions. The HJ chews also revealed a longer duration between the onset of EMG burst for the PT muscle and the beginning of the centric occlusion ( p ⩽ 0.0146). The OI muscle showed increased activity in accord with jaw opening, and consistent reciprocal cyclic activity with the PT muscle in terms of temporal associations ( r ⩾ 0.5250; p ⩽ 0.0495). The OI muscle started to burst at a later part of the intercuspal phase, and frequently showed secondary activity in the jaw-closing and intercuspal phases. The peak activity for the ipsilateral OI muscle was significantly higher ( p ⩽ 0.0106) than that for the contralateral OI muscle for both the HJ and SJ. The OI muscle activity, however, did not differ between the hard and soft jellies. Thus the number of chews and the time elapsed from the start of chewing until the completion of the final swallowing of food in a chewing sequence increased when chewing a harder food. Also, the PT and OI muscle activity and associated jaw-movement patterns appear to be centrally regulated but peripheral information on food consistency might also modify the motor output to the PT muscle. The consistency of food, however, might not be influential in modulating the basic form of perioral motility during chewing.

Electromyographic and Cephalometric Findings in Patients with Unilateral Cleft Lip and Palate After the Use of a Special Removable Appliance

Cephalometric measurements and electromyographic analysis of the superior orbicularis oris muscle were undertaken in 13 children with unilateral cleft lip and palate with a short upper lip length who have undergone surgery in childhood. Initially, cephalometric and electromyographic records were evaluated and again after the subjects had continuously worn, for 4 months, a removable appliance specially designed to avoid the restraining effect of superior orbicularis oris muscle activity over the maxilla. Comparison between pretreatment and posttreatment cephalometric measurements showed a significant improvement in both the sagittal position of the maxilla and the dentoalveolar position. No significant changes were observed in electromyographic activity during rest or when saliva swallowing. Cephalometric changes suggest that the removable appliance used improves the growth of the maxilla.

Electromyographic and Cephalometric Findings in Patients with Unilateral Cleft Lip and Palate after the Use of a Special Removable Appliance

Cephalometric measurements and electromyographic analysis of the superior orbicularis oris muscle were undertaken in 13 children with unilateral cleft lip and palate with a short upper lip length who have undergone surgery in childhood. Initially, cephalometric and electromyographic records were evaluated and again after the subjects had continuously worn, for 4 months, a removable appliance specially designed to avoid the restraining effect of superior orbicularis oris muscle activity over the maxilla. Comparison between pretreatment and posttreatment cephalometric measurements showed a significant improvement in both the sagittal position of the maxilla and the dentoalveolar position. No significant changes were observed in electromyographic activity during rest or when saliva swallowing. Cephalometric changes suggest that the removable appliance used improves the growth of the maxilla.

Superior Orbicularis Oris Muscle Activity in Children with and without Cleft Lip and Palate

Superior Orbicularis Oris Muscle Activity in Children with and without Cleft Lip and Palate

Superior Orbicularis Oris Muscle Activity in Children with and without Cleft Lip and Palate

An analysis of integrated electromyographic (IEMG) activity of the superior orbicularis oris muscle was undertaken in 15 children with cleft lip and palate who have undergone surgery compared to 10 children without clefts (control group). Bipolar surface electrodes were used for IEMG recordings of resting level activity and during the swallowing of saliva. Similar resting level activity was observed in both groups. During the swallowing of saliva, activity in children with cleft lip and palate was higher than in children without clefts (noncleft children). Moreover, in the cleft lip and palate group, children with abnormal lip seal showed the highest values for IEMG activity during the swallowing of saliva. This fact suggests that with each swallow of saliva, a greater counteracting effect of the superior orbicularis oris muscle could be produced on the growing maxilla. This may result in a significant long-term effect on the growth of the stomatognathic system, since the process of swallowing is a 24-hour function repeated between 600 and 2400 times each day.

Associations between anterior temporal, masseter, and orbicularis oris muscle activity and craniofacial morphology in children

In a sample of children with Class I (n = 18), Class II, Division 1 (n = 25) and Class II, Division 2 (n = 12) malocclusions, the relationship between jaw muscle activity and specific craniofacial variables has been quantified. Muscle data were obtained from the temporal, masseter, and orbicularis oris muscles at rest, in maximum intercuspation, and during clenching, jaw opening, and swallowing. Contrasts in means of the three skeletal groups identified differences in both the craniofacial and muscle variables. Orbicularis oris muscle amplitude was greater at rest and in maximum intercuspation in Class II, Division 2 subjects. Anterior temporal amplitude during clenching was significantly lower in Class II, Division 1 subjects. A principal component analysis reduced the data base, and three canonical correlations were identified at the 0.05 level of significance. Significant canonical correlations could not be found between the cephalometric data and clench, swallow, or jaw-opening tasks, which suggests no dependency between these factors. Two canonical correlations were found for the rest position data. A linear combination of masseter and orbicularis oris activity and incisor separation was correlated (r 1 = 0.758) with a linear combination of mandibular unit length, upper and lower central incisor angulation, and SNOP. The second rest canonical correlation (r 2 = 0.733) involved the anterior temporal muscle and a series of sixteen cephalometric variables. For the maximum intercuspation data, orbicularis oris amplitude was correlated with a linear combination of upper incisor angulation and SNOP variables (r 1 = 0.727). The multivariate statistical analysis extracted a clinically significant association between orbicularis oris muscle activity and incisor position.

Correlations between orofacial muscle activity and craniofacial morphology in a sample of control and anterior open-bite subjects

In order to investigate the correlations between genioglossus, masseter, and orbicularis oris muscle activity and craniofacial morphology, an electromyographic and cephalometric analysis was undertaken on a series of twenty-four human subjects. The activity from the muscles was recorded during voluntary opening movements of the mandible monitored by an electronic transducer. A computer-based method was devised to calculate the threshold incisor-separation position corresponding to a 20 percent increase in base line muscle activity for each of the muscles. 19 In addition, twenty-seven anatomic points were digitized from lateral head films, and a computer-based cephalometric analysis was completed for each subject. A number of significant correlations were found between the threshold muscle values and the thirty-one linear and angular morphologic variables. Low threshold values for the genioglossus muscle were correlated with negative overbites, undererupted maxillary and mandibular incisors, and low total face heights. Low threshold values for the masseter muscle were also associated with low overbite measurements. In contrast, orbicularis oris muscle thresholds did not appear to be correlated with any of the craniofacial variables measured. This interdependence of tongue and jaw muscle activity and facial morphology suggests a contribution of the musculature to the development and/or maintenance of the dentition.

Tongue and jaw muscle activity in response to mandibular rotations in a sample of normal and anterior open-bite subjects

In order to investigate the effect of mandibular rotations in human subjects, the electromyographic activity from the left GG, left masseter, and left orbicularis oris muscles was recorded during voluntary opening movements of the mandible that were monitored by an electronic transducer. For each muscle, a computer-based system was used to calculate a threshold incisor-separation position corresponding to a 20 percent increase in base line muscle activity. The mean threshold level for the GG muscle in a sample of twenty subjects with normal occlusions was 53.0 percent (S.D. ± 22.8) of maximum jaw opening. By contrast, a sample of nine subjects with anterior open-bite malocclusions had a statistically significant (p < 0.001) lower mean threshold of 5.9 percent (S.D. ± 4.5) of maximum jaw opening. No significant differences in masseter or orbicularis oris muscle activity were found between the two samples. Since postural tongue activity could play an important role in the development of the anterior dentition, the lower threshold for the GG muscle activity in response to jaw opening in anterior open-bite subjects may be of significant clinical importance.