Perubahan lebar interkaninus rahang atas dengan penggunaan sekrup ekspansi pada jarak waktu aktivasi yang berbedaChanges in the maxillary intercanine width during the use of expansion screws at different activation intervals

ABSTRAKPendahuluan: Penggunaan sekrup ekspansi pada ortodonti lepasan dilakukan untuk melebarkan lengkung gigi. Lebar lengkung gigi dapat diukur salah satunya dengan cara menghitung lebar interkaninus. Tujuan dari penelitian ini adalah untuk mengetahui evaluasi penggunaan sekrup ekspansi terhadap perubahan lebar interkaninus rahang atas berdasarkan kelompok waktu aktivasi. Metode: Metode penelitian yang digunakan adalah analitik. Teknik pengambilan sampel menggunakan purposive sampling. Hasil:. Berdasarkan hasil perhitungan analitik nilai t stat memiliki nilai yang lebih kecil dari nilai t Critical two-tail, maka didapatkan hasil yang menunjukan bahwa terdapat perbedaan yang bermakna dari perubahan lebar interkaninus pada dua kelompok waktu tersebut. Simpulan: Terdapat perubahan lebar interkaninus yang signifikan pada kedua kelompok waktu aktivasi.Kata kunci: sekrup ekspansi, ortodonti lepasan, lebar interkaninus, rahang atasABSTRACTIntroduction: The use of expansion screws in removable orthodontics is used to widen the dental arch. The dental arch width can be measured one of them by calculating the intercanine width. The aim of this study was to evaluation the use of expansion screws for changes in maxillary intercanine width based on activation time groups. Method: This research used analytic method. The sampling technique used purposive sampling. Results: Based on the results of analytical calculations, the value of t stat has a value smaller than t Critical two-tail, the results obtained indicate that there are significant differences in changes in intercanine width in the two time groups. Conclusion: There was a significant change in intercanine width in both groups of activation time. Keywords: expansion screws, removable orthodontics, intercanine width, maxillary

Analysis of the activation modalities of the lower limb muscles during walking

BACKGROUND: Walking is a basic human activity and many orthopedic diseases can manifest with gait abnormalities. However, the muscle activation intervals of lower limbs are not clear. OBJECTIVE: The aim of this study was to explore the contraction patterns of lower limb muscles by analyzing activation intervals using surface electromyography (SEMG) during walking. METHODS: Four muscles including the tibialis anterior (TA), lateral gastrocnemius (LG), medial gastrocnemius (MG), and rectus femoris (RF) of bilateral lower extremity of 92 healthy subjects were selected for SEMG measurements. The number of activations (activation intervals) and the point of the highest root mean square (RMS) EMG signal in the percentage of the gait cycle (GC) were used to analyze muscle activities. RESULTS: The majority of TA and RF showed two activation intervals and both gastrocnemius parts three activation intervals during walking. The point of the highest RMS EMG signal in the percentage of the GC for TA, LG, MG and RF are 5%, 41%, 40%, and 8%, respectively. The activation intervals were mostly affected by age, height, different genders and bilateral limbs. CONCLUSION: This study identified the different activation intervals (four for each muscle) and the proportion of healthy adults in which they occurred during the normal gait cycle. These different activation intervals provided a new insight to evaluate the function of nerves and muscles. In addition, the activation interval and RMS peak time proposed in this study can be used as new parameters for gait analysis.

Gamma Oscillatory Activity Related to Language Prediction

Using magnetoencephalography, the current study examined gamma activity associated with language prediction. Participants read high- and low-constraining sentences in which the final word of the sentence was either expected or unexpected. Although no consistent gamma power difference induced by the sentence-final words was found between the expected and unexpected conditions, the correlation of gamma power during the prediction and activation intervals of the sentence-final words was larger when the presented words matched with the prediction compared with when the prediction was violated or when no prediction was available. This suggests that gamma magnitude relates to the match between predicted and perceived words. Moreover, the expected words induced activity with a slower gamma frequency compared with that induced by unexpected words. Overall, the current study establishes that prediction is related to gamma power correlations and a slowing of the gamma frequency.