Background: This study compared the area and minimal section of the nasal cavity, nasopharynx, oropharynx, and hypopharynx in cases treated with different methods of microimplant-assisted expansion. Methods: Based on a pilot study to calculate the sample size, 30 patients with transverse maxillary deficiency over 14 years of age were retrospectively selected. These patients had received two different types of microimplant-assisted maxillary expansion treatment (MARPE and BAME). The patient underwent Cone-Beam computed tomography (CBCT) before and after treatment (mean time 1.5 months) with MARPE or BAME and upper airway measurements (volume and minimum cross-sectional area) were taken to assess upper airways changes and compare changes between the groups. A paired sample t-test was performed to evaluate the T0-T1 change of airway measurements obtained with MARPE and BAME, and a student t-test to compare changes in airway measurements between MARPE and BAME. Results: This investigation shows a statistically significant increase in total nasopharyngeal airway volume (0.59 ± 1.42 cm3; p < 0.01), total oropharyngeal airway volume (3.83 ± 7.53 cm³; p < 0.01) and minimum oropharyngeal cross-section (53.23 ± 126.46 mm²; p < 0.05) in all cases treated with micro-screw assisted expansion. The minimal cross-sectional area of the oropharynx ((79.12 ± 142.28 mm2; p < 0.05) and hypopharynx (59.87 ± 89.79 mm²; p < 0.05) showed significant changes for cases treated with BAME. As for the comparison between cases treated with MARPE and BAME, no differences in upper airway changes have been observed, except for the minimum cross-sectional area of the nasal cavity, which increases for MARPE (52.05 ± 132.91 mm2) and decreases for BAME (-34.10 ± 90.85 mm2). Conclusions: A significant increase in total area and minimal section at the level of nasopharynx and oropharynx was observed in cases treated with BAME. Regarding the comparison of MARPE and BAME treatments, no differences were found in the total airway volume and minimal section in upper airway except for the minimum cross section of the nasal cavity that increases for MARPE and decreases for BAME.

This study compared the buccolingual angulation (BLA) of the upper and lower first permanent molars before and after using the different methods of microimplant-assisted expansion in adults and its influence on bone insertion loss. Methods: Cone-beam computed tomography scans taken before and after the expansion in 36 patients (29.9 ± 9.4 years) were used to assess dental and periodontal changes and compare changes between the groups. Results: This research shows a statistically significant increase in the BLA of the upper first molars. An increase of the BLA of the lower molars is also observed in MARPE. Regarding the comparison between cases treated with MARPE (4.42° ± 10.25°; 3.67° ± 9.56°) and BAME (−0.51° ± 4.61°; 2.34° ± 4.51°), it was observed that upper molar torque increased significantly less in cases treated with BAME. In cases with CWRU < 96° at T0, a slight bone insertion gain was observed at T1, whereas if CWRU ≥ 96°, a slight bone insertion loss was observed. Regarding the labial cortical bone loss, a slight gain of CBW was observed in all cases. This labial cortical enlargement (T0–T1) is greater in cases where the CWRU < 96° at T0. Conclusions: Patients treated with MARPE show torque increase in the teeth selected to support the expansion appliance compared to cases treated with BAME. In cases where the BLA at T0 < 96°, an increase in thickness and cortical insertion is observed in the upper molars after treatment with disjunction appliances assisted with microscrews.

Microimplant-assisted rapid palatal expansion (MARPE) is a technique widely used to treat transverse discrepancies in adult patients. The present study aims to examine how age, sex, maxillary width, and suture bone density might influence MARPE efficacy. It also analyzes bone density variations across the midpalatal suture regions. Materials and Methods: This retrospective study included 30 adult patients who underwent MARPE treatment. Pre- and post-treatment CT scans were analyzed to quantify the maxillary width and bone density measured in Hounsfield units (HUs) in the anterior, middle, and posterior nasal spine regions. Statistical analyses were carried out and included descriptive statistics, t-tests, and effect size calculations. Results: Younger patients (age 22.13 ± 4.58) had significantly higher success rates compared to older patients (aged 25.66 ± 4.67). No significant differences were found regarding sex or the initial maxillary width. Lower bone density in the middle and posterior nasal spine regions was correlated with higher success rates. Data showed that the anterior nasal spine exhibited higher bone density, but this finding did not affect treatment outcomes significantly. Conclusions: Age seems to be a crucial factor in MARPE success, with younger patients showing better outcomes. Regarding bone density, results showed that its values in the middle and posterior nasal spine regions could be a determinant of treatment success. On the contrary, sex and the initial maxillary width did not appear to affect outcomes. These findings emphasize the importance of preoperative assessments and the consideration of individual anatomical variations for optimal MARPE treatment planning.

Posterior crossbite in children and adolescents has been linked to asymmetrical function and performance of the masticatory muscles. Electromyography (EMG) serves as an objective and widely applicable evidence-based method for diagnosing muscle function. The aim of our study was to analyze electromyographic (EMG) activity of muscles of the craniomandibular system in subjects with a narrowing upper jaw and unilateral posterior crossbite. Material and methods. The first (study) group consisted of 18 subjects with narrow maxilla and unilateral posterior crossbite. 20 age-matched children with normal occlusion were included in the control group. The average age of subjects in the study group was 8.4±1.4 years, in the control group – 8.8±1.6 years. The exclusion criteria of the study were as follows: previous or active orthodontic treatment, clefts, traumas in the maxillofacial region, and general diseases. EMG activity of the anterior temporal, masseter, sternocleidomastoid (SCM), orbicularis oris, and mentalis muscles on both sides (left and right) was recorded during two 30-second tests: maximum voluntary clenching and swallowing a sip of water. Maximum voluntary clenching was performed in the intercuspal position. EMG data were processed using Neurotech's Synapsis software. EMG activity for each muscle was estimated by the maximum amplitude of the muscle contractions (μV). Results. EMG activity in children with narrowing upper jaw and unilateral posterior crossbite of anterior temporal, masseter, and sternocleidomastoid muscles was asymmetrical and differed between the left and right sides. Higher bioelectrical muscle activity was found on the crossbite side for the masseter and anterior temporalis muscle, and on the opposite side – for sternocleidomastoid muscles. Values of maximum amplitude of sternocleidomastoid muscles were higher in the study group than in the control group without significant difference. There was a statistically significant difference in EMG activity of mentalis and orbicularis oris muscles between the two groups of children (p<0.05). Values of EMG activity of mentalis and orbicularis oris were higher in the study group. Перехресний прикус у дітей і підлітків пов’язаний з асиметричною роботою жувальних м’язів. Об’єктивним, доказовим методом функціональної діагностики активності м’язів щелепно-лицевої ділянки є електроміографія (ЕМГ). Метою нашого дослідження було проаналізувати електроміографічну (ЕМГ) активність м’язів краніо-мандибулярної системи в осіб зі звуженням верхньої щелепи та одностороннім перехресним прикусом. Матеріали та методи. Дослідну групу склали 18 осіб зі звуженням верхньої щелепи та одностороннім перехресним прикусом. До контрольної групи увійшли 20 дітей відповідного віку з нормальним прикусом. Середній вік обстежених дослідної групи становив 8,4 ± 1,4 років, контрольної – 8,8 ± 1,6 років. Критеріями виключення з дослідження були: попереднє або активне ортодонтичне лікування, незрощення, травми щелепно-лицевої ділянки, загальні захворювання. За допомогою поверхневої ЕМГ визначали біоектричну активність переднього скроневого, жувального, груднино-ключично-соскоподібного м’язів з лівої та правої сторін, підборідного, кругового м’яза рота у 2 пробах, тривалістю 30 с кожна: максимальне довільне стискання зубів з обох сторін, ковток води. Дані ЕМГ обробляли за допомогою програмного забезпечення Synapsis компанії Neurotech. ЕМГ-активність для кожного м’яза оцінювали за максимальною амплітудою м’язових скорочень (мкВ). Результати. ЕМГ-активність у дітей зі звуженням верхньої щелепи та одностороннім перехресним прикусом переднього скроневого, жувального та грудинно-ключично-соскоподібного м’язів була асиметричною та відрізнялася між лівою та правою сторонами. Вищу біоелектричну активність виявлено на боці перехресного співвідношення зубів для жувального та переднього скроневого м’язів, з протилежного боку – для груднино-ключично-соскоподібного м’яза. Значення максимальної амплітуди груднино-ключично-соскоподібних м’язів були вищими в дослідній групі, ніж у контрольній без достовірної різниці. Між двома групами дітей виявлено статистично значущу різницю ЕМГ-активності підборідного та колового м’яза рота (р<0,05). Значення їх...