Introduction: Extraction vs. non-extraction is a crucial decision in orthodontic therapy. Objective: The aim of the present study was to investigate the changes in the dental arch width and buccal corridor after orthodontic treatment using extraction and non-extraction therapy with Damon self-ligating system. Material and Methods: This retrospective study consisted of 35 patients (20 female and 15 male patients with median age of 12.5 years), treated by extracting 4 or 2 premolars, and 37 patients (16 female and 21 male patients with the median age of 12.8 years), treated without premolar extraction. Both groups were treated with Damon self-ligating system. Plaster models before (T0) and after (T1) treatment were measured, and the arch width values were determined at the level of the first molars, second premolars, canines and palatal rugae. Buccal corridor width was measured using the extraoral images at T0 and T1. Paired t-test was used for the analysis of the normally distributed data, and Wilcoxon Mann-Whitney U test was used for the data with non-normal distribution. Values of p<0.05 were set as statistically significant. Results: The upper intercanine width increased significantly in both groups (p<0.01). In the non-extraction group, the arch width increased significantly in the maxillary second premolar and first molar region (p<0.01) as well as in the region of the canines (p=0.04), second premolars (p=0.01) and first molars (p<0.01) of the mandible. The buccal corridor decreased significantly in the non-extraction group (p<0.01). Conclusion: Premolar extraction in combination with Damon self-ligating system did not lead to reduction of the dental arch width in the maxilla, nor did it increase the size of the buccal corridors.

As advancements in digital technologies reshape the modern healthcare, integrating digital impression techniques, such as intraoral 3D scanning and 3D analysis and treatment planning, is becoming increasingly essential in the standard care of infants with cleft lip and palate. This study introduces a novel digital measurement method designed specifically for analyzing digital models of infants with unilateral cleft lip and palate, utilizing OnyxCeph³™ software within the interdisciplinary framework of the Frankfurt approach. To support its integration into routine clinical practice, we outlined the complete digital workflow—from data acquisition through intraoral 3D scanning to model preparation and processing. Our method involves precise anatomical and constructed measurement points and diverse distances and angles to evaluate sagittal, transverse, and vertical parameters comprehensively. By leveraging OnyxCeph³™ software for computer-aided measurements of digital 3D models, this approach aims to enhance the accuracy and efficiency of cleft treatment planning, facilitating more informed, personalized care decisions and ultimately improving patient outcomes.

The association between the visceral swallowing pattern (VSP) and dentofacial abnormalities remains controversial. This cross-sectional study aimed to investigate the association between the VSP and various factors including type of birth, gender, tongue posture, lip incompetence, eruption of primary molars, habits and the presence of malocclusions in children with primary and early mixed dentition. A total of 219 children (102 boys and 117 girls) were evaluated using a combination of a questionnaire and a structured clinical examination by one pediatric specialist dentist. Kittel’s method of tongue posture evaluation and the Payne technique for assessment of swallowing pattern were included in the clinical examination of myofunctional status. After checking for normality, normal and non-normal distributed data were analyzed using two-sample t-test and Mann-Whitney U test, respectively. Analysis of categorical variables was done using a chi-square test, and Bonferroni correction was used as correction for multiple comparisons. A total of 56.2 % of the study population had a VSP. The chi-square test indicated a statistically significant higher presence of VSP in male gender. Statistically significant associations were seen between the VSP and lip incompetency, pathologic resting tongue position, habits, anterior open bite and increased overjet. On the other hand, no statistically significant associations were found between VSP and children’s age within the sample population, type of birth, uni- or bilateral crossbites, increased overbite, edge-to-edge anterior bite or completion of eruption of primary molars and/or permanent incisors. The association between VSP and male gender, pathologic tongue posture, lip incompetency and habits and occlusal traits such as anterior open bite and increased anterior overjet is supported by the results of the present study.

Background: This retrospective study aimed to analyze the frequency and extent of apical root resorptions (EARR) during orthodontic treatment in the upper and lower incisors, as well as lower molars, using orthopantomograms (OPG). Potential influencing factors such as age, gender, root shape, type of orthodontic appliance, and treatment duration were examined as well. Methods: A total of 57 patients who completed their treatment at the orthodontic department of the Goethe University of Frankfurt between 2011 and 2018 were included in the study. These patients had a combined total of 570 teeth, which were divided into two groups. Group 1 consisted of 20 patients (average age at T0: 10.1 ± 1.2 years old) received a one-phase fixed orthodontic treatment using passive self-ligating Damon bracket system (average duration of 2.1 years ± 6 months), while group 2 consisted of 37 patients (average age at T0: 12.4 ± 2.8 years old) underwent a two-phase therapy, which involved a phase-one functional therapy (average duration of 1.7 years ± 6 months) prior to the phase-two fixed orthodontic treatment with the Damon system (average duration of 1.5 ± 4 months) with a total treatment time of 3.2 years ± 7 months. To determine the extent of post-treatment root resorption of the upper and lower incisors, as well as the first lower molars, crown–root ratio was calculated for each tooth using the pre- and post-treatment OPGs. Additionally, each tooth was assigned a degree of resorption according to the Levander and Malmgren classification. The inter-group comparisons were conducted using the Wilcoxon Mann–Whitney U test. Spearman’s correlation analysis was used to assess the relationship between age, treatment duration, and EARR. The association between gender, root morphology, and EARR was evaluated using the Wilcoxon Mann–Whitney U test. For nominally scaled variables, the Chi-square test was used. The statistical significance was set at p < 0.05. Results: No statistically significant differences were seen between groups 1 and 2 regarding the degree of root resorption (p = 0.89). The study found that the average root resorption for all examined teeth was −5.14%, indicating a slight reduction in the length of the tooth roots after orthodontic treatment. However, no significant differences were observed concerning gender, age, type of orthodontic appliance or treatment duration. Comparisons between upper and lower jaws also did not yield statistically significant differences. The majority of teeth in the study exhibited a normal root shape. The short root length and a pipette formed roots were significantly associated with a higher risk of root resorption (p = 0.001). Conclusions: The study’s findings suggest that the two-phase orthodontic treatment does not increase the risk of EARR compared to one-phase therapy significantly. Some degree of root resorption occurred as a result of orthodontic treatment in both groups. Notably, abnormal root forms were identified as influential factors that could help predict the likelihood of root resorption following orthodontic treatment.

Background: This study investigated the effects of preoperative maxillary plates on cleft width reduction in infants with unilateral cleft lip and palate and their control group. The study also aimed to compare the digital and manual methods in measurement of changes in maxillary segment positioning in sagittal and transverse dimensions using digital 3D models and conventional plaster casts. Methods: Twenty infants with unilateral cleft lip and palate and their control group of eleven infants with isolated cleft palate were enrolled in a prospective interventional study (2020 to 2024). Participants were treated with either active or passive maxillary plates. Sagittal, transversal and angular measurements were taken both manually as well as digitally at three time points: 24–48 h postnatal (T0), approximately at six months old (T1, immediately before surgery), and one year postoperatively (T2). Results: Significant reductions in cleft width were observed across all patients over the treatment period, regardless of the type of plate used (p < 0.001). The mean cleft width reduction was 5.050 mm. Infants treated with active plates had a larger reduction in cleft width than those with passive plates (p = 0.024), averaging 5.846 mm compared to 3.571 mm. Neither the side of the cleft nor the patient’s gender influenced the degree of cleft reduction (p = 0.884 and p = 0.245, respectively). The study found significant modifications in the maxilla’s transverse, sagittal, and angular dimensions (p < 0.001). When comparing sagittal growth, the study group differed from the control group (p = 0.004), with isolated cleft palate patients showing more substantial sagittal expansion. Additionally, the overall change in the ITT’ distance differed significantly between the study and control groups over time (p < 0.001). Cleft size at baseline did not affect the extent of changes within the cleft area. No significant discrepancies were found between digital and manual measurement methods, confirming the reliability of both. Conclusions: Active plates demonstrated greater efficacy in cleft reduction for wider and more divergent clefts, while passive plates were suitable for smaller clefts.

Purpose: The aim of the study was to identify the best prediction model for the growth pattern of the maxillary segments of infants with unilateral cleft lip and palate post birth and prior to the primary surgical cleft closure. Materials and methods: 195 digital maxillary models of 50 infants with unilateral cleft lip and palate were collected during their preoperative alveolar molding therapy period. Intraoral scans were taken shortly after birth, at the monthly checkups and just before the surgical cleft closure at approximately 6 months of age. Surface measurements of maxillary segments were conducted using the diagnostic program OnyxCeph³™. For identifying the best fit for the growth pattern, mixed-effects regression models (fractional polynomials and B-splines) with the surface measurement as dependent variable, patient age (days) as predictor and the patient as random effect were fitted to the data. The best fit was selected according to the Akaike Information Criterium. A likelihood ratio test was performed for comparing the selected model with the intercept-only model. Results: The linear regression with mixed effects model showed the best fit for the total area, the area of the large segment and the area of the small segment. A highly significant association between the surface area and patient age was observed (p < 0.001). An increase of the area with time was estimated at 2.88 mm² per day for the total area, 1.62 mm² per day for the area of the large segment and 1.25 mm² per day for the area of the small segment. The likelihood ratio tests indicated that the linear regression models were significantly better than the intercept-only models for all the measured areas (p < 0.01). Conclusion: The growth pattern for the maxillary segments of patients with unilateral cleft lip and palate in the preoperative period can be best predicted by using a linear regression model. The growth curve model developed by the present study can be used in future treatment planning of patients with unilateral cleft lip and palate.