A Comparison Between Skeletal Class II and Class III Malocclusion Patients in Terms of the Masticatory Muscles' Activity: A Cross-Sectional Study.

Background This study aimed to determine if individuals with skeletal Class II and skeletal Class III malocclusions had different levels of masticatory muscle activity. Materials and methods This cross-sectional study, conducted at the University of Damascus, investigated the myoelectric activity of perioral muscles in patients with Class II and III malocclusions. The sample size of 60 patients was determined according to a prior sample size calculation. Patients were selected based on specific inclusion and exclusion criteria and divided into Class II and III groups. Electromyography was used to monitor the activity of various muscles, including the temporalis, masseter, orbicularis oris, buccinator, mentalis, and digastric muscles. Results The study found similar muscle activity within the same group in the temporalis, masseter, buccinator, digastric, and orbicularis oris muscles. No significant differences were observed between the Class II and III groups for several oral and perioral muscles (P > 0.05). However, the mean activity of the digastric muscle was significantly greater in the Class II group (P < 0.05), whereas the mean activity of the mentalis muscle was smaller in the Class II group (P < 0.05). Conclusions Perioral muscles influence facial complex development and jaw relationship, affecting orthodontic treatment. Digastric muscle activity is greater in Class II patients, while mental muscle activity is smaller in Class III patients. Further studies are needed for older age groups and other skeletal malocclusion types.

Evaluation of Patient-Reported Outcome Measures (PROMs) Associated With the Acceleration of Canine Retraction by Piezosurgery in Comparison With Low-Level Laser Therapy: A Three-Arm Randomized Controlled Clinical Trial.

Background and objectives Recently, both surgical and non-surgical interventions have gained popularity in accelerating orthodontic tooth movement, but there is no randomized controlled trial (RCT) comparing both modalities in terms of patient-reported outcome measures (PROMs) during maxillary canine retraction. Therefore, this trial aimed to assess the PROMs associated with either low-level laser therapy (LLLT) or piezocision-assisted acceleration in the context of maxillary canine retraction. Materials and methods This was a single-blinded, single-center, three-arm RCT. A total of 54 patients (12 males, 42 females, mean age 20.65 ± 2.85) whose treatment needed upper-first-premolar extraction to facilitate canine retraction were enrolled and randomly divided into three groups: piezocision group (PG), LLLT group (LLLTG), and the control group (CG). Standardized questionnaires using a visual analog scale were distributed to patients at five assessment times: 1 (T1), 3 (T2), 7 (T3), 14 (T4), and 28 days following the canine retraction initiation (T5). The patients' pain, discomfort, swelling, chewing difficulty, satisfaction, and acceptance were recorded. Results Regarding pain and discomfort, the levels were significantly lower in the LLLTG during the first two weeks of canine retraction compared to the other two groups (p<0.017). At the same time, these levels were significantly greater in the PG than the CG in the first week of canine retraction (p<0.017). Patients in the PG had a "mild to moderate" perception of swelling at T1 and T2, which was significantly different than that of the other two groups (p<0.001). Regarding chewing difficulty, the levels in the LLLTG were significantly lower than those in PG at the first three assessment times (p<0.017). Patients' satisfaction with canine speed was significantly greater in the intervention groups compared to the CG (p<0.001). In contrast, no statistically significant differences were found between the three groups regarding satisfaction with gum appearance surrounding the canine (p=0.061) and acceptance (p=0.125). Conclusion The LLLT-assisted canine retraction was associated with significantly lower negative patient-reported outcomes during the first two weeks of retraction than piezocision-assisted retraction. However, the levels of pain and discomfort were significantly greater in the piezocision-assisted retraction group than those in the conventional canine retraction group, which in turn were greater than those with the LLLT-assisted canine retraction group during the first week of retraction. Patient satisfaction and acceptance were high with both piezocision and LLLT interventions.

The diagnostic accuracy of cone-beam computed tomography and two-dimensional imaging methods in the 3D localization and assessment of maxillary impacted canines compared to the gold standard in-vivo readings: A cross-sectional study.

BACKGROUND: Although the widespread cone-beam computed tomography (CBCT) is a diagnosing tool for impacted canines, the surgical exposure-based diagnostic accuracy of this 3D imaging modality has not been established yet. Therefore this study aimed to (1) compare the accuracy of CBCT- and 2D-based interpretations of impacted canine and its relationships with the neighbouring structures with the gold standard (GS) readings, (2) and calculate the diagnostic accuracy, sensitivity, and specificity values of the variables assessed using CBCT and 2D methods. MATERIAL AND METHODS: Patients with unilateral impacted maxillary canines (IMCs) planned for surgical extraction between 2016-2018 were checked in-depth to include in this cross-sectional study. For each patient, 2D and 3D radiographic records were obtained and assessed by eight postgraduate orthodontic students. These assessments were compared with the GS readings based on surgical exposure and direct vision of the IMCs. To compare 2D- and CBCT-based assessments with the GS values, Cochran's Q tests, Friedman's tests, McNemar's, McNemar-Bowker's, and Wilcoxon tests were applied. RESULTS: A total of 17 patients (6 males, 11 females; mean age: 20.52±3.98 years) were randomly selected and included in this study. Significant differences were found between the CBCT-based assessments and the GS only concerning shape and bony coverage of the IMC (P=0.001 and P<0.001, respectively). On the contrary, there were significant differences between the 2D-based assessments and the GS regarding all the assessed variables except for the ankylosis and the proximity to the adjacent teeth (P=0.424, and P=0.080, respectively). CBCT-based assessments had remarkably higher values of diagnostic accuracy, sensitivity, and specificity compared to 2D-based ones. CONCLUSIONS: The diagnostic accuracy of CBCT outperformed 2D radiography in localizing the IMC (labiopalatal, mesiodistal, and vertical location), detecting root apex development of the IMCs, and the resorption of the adjacent incisors. Although both 2D and 3D techniques showed the same ability in the diagnosis of IMCs ankylosis, the diagnostic accuracy of CBCT was superior. However, both techniques inaccurately determined the shape of the impacted canine and the bony coverage.

Evaluation of the Patient-Reported Outcome Measures (PROMs) With Temporary Skeletal Anchorage Devices in Fixed Orthodontic Treatment: A Systematic Review.

Analysis of patient-reported outcome measures (PROMs) is essential to ensure that the skeletal and traditional anchoring methods are appropriately and effectively utilized in the context of patient acceptance and satisfaction. This review's objective was to assess the available data on the levels of discomfort, soft-tissue irritation, functional impairment, and other patient-reported outcomes related to the usage of mini-implants in the context of fixed orthodontic treatment for adult patients. A total of seven electronic bibliographic databases were searched between January 1995 and February 2022. Moreover, a manual search was done in the selected orthodontic journals. This systematic review (SR) covered cohort studies, retrospective studies, randomized clinical trials (RCTs), and controlled clinical trials (CCTs) that studied the use of mini-implants, mini-plates, or onplants as anchorage devices on patients receiving orthodontic treatment. The risk of bias was assessed using Cochrane's risk of bias tool (RoB2 tool). Three RCTs and two cohorts were included in this SR with a total of 468 patients. Three of the four included studies were at high risk of bias. The pain level was in the "mild-to-moderate" category on the first day following the insertion of mini-implants, then decreased to a mild level from the fifth day to the seventh day of insertion (mean values are 36.61, 16.36, and 11.33, respectively). The levels of functional impairments were found to be located between the "mild-to-moderate" and "moderate" categories after the placement of mini-plates and intermaxillary fixation screws, while they experienced a mild level with mini-implants. The greatest pain levels were found after the insertion of the temporary anchorage devices (TADs) and then decreased until they became mild or disappeared completely after one month. Speaking, chewing, and cleaning difficulties were more problematic when using TADs compared to conventional anchorage. To obtain good evidence in this area, more high-quality RCTs are needed.