(1) We aimed to compare articular eminence inclination (AEI) in normo-divergent subjects (SN^GoGn = 32° ± 5°), with different anteroposterior sagittal skeletal classes through a cone beam computed generated tomography (CBCT). (2) In this cross-sectional study, CBCT records were retrospectively analysed. From the original sample of 52 CBCT records, 33 records of normo-divergent adult subjects were selected (11 Class I, 13 Class II and 9 Class III). On mid-sagittal section of the Temporomandibular Joint (TMJ) on both sides, AEI was calculated by graphic method. (3) The Kruskal–Wallis test was used to evaluate any difference between AEI on both left and right sides in the three groups. No statistically significant difference was observed on either the right side (p = 0.174) or the left side (p = 0.624). (4) Articular eminence inclination seems to be not related with skeletal class. Given the lack of significance in the observed differences between AEI and skeletal classes, we believe that future studies should focus on assessing possible relationships between AEI and different vertical skeletal patterns.

To investigate temporomandibular joint (TMJ) involvement signs such as muscle pain, the ratio of masseter and temporal muscle activity, mouth opening width and jaw deviation during mouth opening in children and adolescents with juvenile idiopathic arthritis (JIA), a group of 32 subjects with JIA and a control group of 32 healthy subjects were evaluated. Data were collected clinically by muscle palpation (masseters, anterior temporalis and sternocleidomastoids) and instrumental analysis (electromyography and kinesiography). Higher pain was registered in the masseter and sternocleidomastoid muscles on both sides and in the right anterior temporalis in the JIA group compared to the control group (p < 0.05). Electromyography showed no statistically significant difference in the frequency of the pathological ratio of masseter and temporal muscle activity (MM/TA < 1) both in the JIA group and in the control group. Kinesiography showed a statistically significant difference in mouth opening width and jaw deviation during mouth opening between the groups (p < 0.05): JIA subjects showed lower mouth opening values and wider deviation on mouth opening; 29 out of 32 JIA subjects showed jaw deviation towards the right side. JIA affects the TMJ, causing myalgia in the head and neck muscles, a reduction in mouth opening width and an increase in jaw deviation during mouth opening.

(1) Background: The aim of the study was to assess the potential effectiveness of clinical diagnostic examinations, such as muscle palpation, and instrumental examinations, such as electromyography, in the early detection of TMJ involvement in patients with juvenile idiopathic arthritis (JIA), as early diagnosis of these disorders can reduce the risk of developing facial growth anomalies and dento-skeletal malocclusions. (2) Methods: Evaluations were conducted on a cohort of 15 people with juvenile idiopathic arthritis (JIA) and a comparison group of 15 healthy participants at the start of the trial (T0) and after 18 ± 6 months (T1). Data were obtained through clinical examination, involving muscle palpation of the anterior temporalis, masseters, and sternocleidomastoids, and by instrumental analysis using electromyography. The parametric student’s t-test was used to evaluate group comparisons for data that were normally distributed, whereas the nonparametric Mann–Whitney U test was employed for parameters that did not follow a normal distribution. (3) Results: In the JIA group, higher levels of pain were recorded in the sternocleidomastoid muscles on both sides as compared to the control group (p < 0.05) at both T0 and T1. Electromyography revealed no statistically significant variances both in the JIA group and in the control group, except for the IMP index, characterized by a significant improvement over time for the JIA group. (4) Conclusions: According to the methodology employed in this study, all JIA patients had TMD symptoms, mainly muscle disorders. The existence of statistically significant parameters suggests the potential to regard muscle palpation and electromyography as predictive indicators of TMJ involvement in JIA subjects. Additional research is required to validate their reliability.

Stomatognathic apparatus and the postural system interact through biomechanical chains, whose neuromuscular properties influence both gross and fine motor coordination. To evaluate changes in body posture and motor functions in children with malocclusion who are treated with palatal expanders, 8 right-handed children (6-12 years) with unilateral posterior crossbite were enrolled in this non-randomized pragmatic longitudinal study. Fine motor skills tests, handgrip strength, 3D body posture analysis, electromyography, thermography and stabilometry were performed before and after the treatment with a Rapid Palatal Expander (RPE) at T0pre (before using RPE), t0Post (immediately after using RPE), T1 (after 21 days of RPE use) and T3 (after 6 months). The positive effect on malocclusion, as demonstrated by reduced mandibular offset, did not result in changes in motor symmetries across time. Velocity variance of stabilometry was reduced during the treatment. The immediate wearing of device only slightly affected the results. The beneficial results at the occlusal level through RPE were not accompanied by changes at the neuromuscular and postural level. Clinicians and practitioners should consider that orthodontics treatments and devices which are adapted due to neuromuscular and posturometric tests may be task and test-related.