The electromyographic and cephalometric analyses after maxillary expansion

The purpose of this study was to evaluate the electromyographic (EMG) activity of the masseter and temporalis muscles and the skeletal and dental behavior of children having slow maxillary expansion with a quadhelix appliance. The study sample consisted of 30 children (mean age = 7 years 4 months;17 girls/13 boys) diagnosed with a unilateral posterior crossbite. Lateral cephalometric tracing and EMG analyses were carried out before orthodontic treatment (T1) and 1 month after removal of the appliance (T2). The EMG activity of the masseter and temporalis muscles was analyzed in two clinical situations: at muscular rest and during habitual chewing. Differences in the measurements were evaluated by using paired t tests. Maxillary expansion with the quadhelix appliance did not promote significant anteroposterior and vertical skeletal alterations. Among the cephalometric variables related to dental pattern, only 1-ANS-PNS values presented a significant increase at T2. At muscular rest, EMG analysis indicated a significant increase in the activity of the temporalis muscle. During habitual chewing, EMG activity decreased significantly for both evaluated muscles after removal of the quadhelix appliance. These alterations suggest an adaptation and reprogramming of the musculature to the new occlusal condition.

Complete dentures with Nobilo's sliding plates:A condylar position and electromyograph analysis

Objective: This study was performed with the purpose a report clinical cases involving condylar position and Nóbilo’s sliding plates. Background: Patients may present temporomandibular disorder (TMD), which is characterized by pain in masticatory muscles, temporomandibular joints and limited mandible movements. Treatment involving oral rehabilitation with the use of complete dentures with Nóbilo’s sliding plates has been an alternative for the treatment of TMD. Materials and Methods: Nine patients with a history of TMD signs and symptoms (RDC/TMD)—in particular, muscular and articular pain—received pain evaluations, mandibular movement analysis, transcranial radiography and an electromyographic analysis of the masseter and temporalis muscles before and after the use of complete dentures with Nóbilo’s sliding plates. Results: After treatment, the patients had reduced painful symptoms, an increase in mandibular movement and adequate electromyographic activity. The normalized EMG data were ta-bulated and analyzed statistically using SPSS version 17.0 for Windows (SPSS Inc., Chicago, IL, USA), and the values were compared by umpaired independent Student’s t-test. Conclusion: The use of Nóbilo’s sliding plates promoted improvements in electromyographic activity, muscular pain and man-dibular movement.

Case report involving temporomandibular dysfunction,eagle’s syndrome and torus mandibularis—Multidisciplinary approaches

The prevalence of torus mandibularis, Eagle’s syndrome and parafunctional activity was reported to be higher in patients with temporomandibular joint dysfunction and might be useful as an indicator of increased risk of temporomandibular disorders. This study case report was to evaluate a 62-year-old female patient, with limited mandibular and cervical movements, articular and muscular pain, ear fullness, irritation of the lingual mucosa, discomfort associated with movement of her tongue, involving temporomandibular dysfunction, torus mandibularis and Eagle’s syndrome. The treatment comprehended the collection of data of Helkimo’s Clinical Dysfunction Index, electromyographic activity of the masseter and temporalis muscles in rest position and bite force, masticatory efficiency, speech evaluation and oclusal splint, after the excision of the stylohyoid process and mandibularis torus. The authors found a decrease in electromyographic activity of masticatory muscles, a reduction of painful symptoms throughout the region muscular and joint pains, an increase in the amplitude of mandibular movements, an improvement in masticatory efficiency and an increase in bite force.

Analysis of the stomatognathic system after anterior cruciate ligamentplasty

Objective: The purpose of this study was to investigate the presence of postural imbalances, which can interfere with the mandible position and affect the actions of the stomatognathic system. Materials and Methods: Forty men, aged between 23 to 29 years, were selected and divided into two groups: Group I comprised 20 healthy individuals with no clinical postural change diagnosis;Group II, 20 individuals who had ACL surgical, unilateral with patellar tendon graft, paired individual to individual (age and weight). All of them were submitted to an electromyography in different clinical conditions. In addition, a condylar biomechanical assessment was performed through videogrametry. Results: In electromyography and videogrametry, a normal standard biomechanical was observed for both groups, however, Group GII—Ligamentplasty presented an inhibition of the masticatory muscles and decreased joint kinesthetic. Conclusion: Based on the results obtained, it was concluded that after the reconstruction of the ACL, individuals presented changes in the stomatog-nathic system.

Changes in sternocleidomastoid and descending portion of trapezius muscles in terms of electromyography and pressure pain threshold: women with chronic neck pain after acupuncture treatment

OBJECTIVE:To evaluate the sternocleidomastoid and the descending portion of the trapezius muscles in terms of electromyographic activity and pressure pain threshold in women with chronic cervical pain after acupuncture treatment.METHODS:Twenty-five women,aged 18-50 years[(31±3)years],with chronic neck and temporomandibular disorder participated in the study.The electromyographic activity of the sternocleidomastoid muscle and the descending portion of the trapezius muscle were recorded at rest,during shoulder elevation,(left and right)rotation of the neck and crucifix position.Maximum voluntary contraction was used to normalize the electromyographic activity data.The points used for acupuncture were Jiache(ST 6),Xiaguan(ST 7),Quanliao(SI 18),Tinggong(SI 19),Yifeng(TE-17),Fengchi(GB 20),Renzhong(GV 26),Yangbai(GB-14),and points of the lower and upper limbs:Tai chong(LV 3),Zusanli(ST 36),Sanyinjiao(SP 6),Kunlun(BL 60),He Gu(LI4)and Yanglingquan(GB 34).The treatment course was 10 sessions,30 min long per session,and twice a week.The final electromyographic activity and pressure pain threshold data collection were performed 15 d after treatment completion.RESULTS:The normalized electromyographic activity and pressure pain threshold data were tabulated and submitted to statistical analysis using t-test(P<0.05).Significant difference was observed during shoulder elevation for the left trapezius muscle,during neck rotation from the right side to the left,and pressure pain threshold for the trapezius and sternocleidomastoid muscles,bilaterally,after the acupuncture treatment.CONCLUSION:The acupuncture treatment improved the neck muscles in terms of electromyographic activity and increased the tolerance to chronic pain in women.