Changes in Andrews' fifth key of occlusion (interproximal contacts) before and after orthodontic treatment.

This study aimed to assess the changes in interproximal contacts before and after orthodontic treatment using the OXIS classification. OXIS refers to the types of contacts that is open (O), point contact (X), straight contact (I), and curved contact (S), and thus the acronym "OXIS". Interproximal contact data of 30 orthodontic patients were obtained at three time points: T0, at the beginning of treatment; T1, at the end of fixed appliance treatment; and T2, one-year post-treatment. For the maxillary second molar-first molar contact, the most common contact at T0, was the "S" pattern (41.6%) which increased to 61.6% at T1 and reduced to 48.3% at T2. For the maxillary first molar-second premolar contact, maxillary second premolar-first premolar contact, and maxillary first premolar-canine contact, the most common contact at T0 was the "I" pattern (58.3%, 46.5% and 43.3%, respectively), which increased to 88.3%, 93.3% and 73.3%, respectively at T1 and decreased to 80%, 88.3% and 71.6%, respectively at T2. For the maxillary canine-lateral incisor contact and lateral-central incisor contact, the most common contact at T0 was the "O" pattern (45% and 33.3%) while it was the "X" pattern at T1 (63.3% and 80%) and T2 (58.3% and 80%). A similar observation was made for the posterior mandibular and anterior teeth. There was statistical significance for most of the changes in the mandibular contacts (p ˂ 0.05). Interproximal contacts change significantly from T0 to T1. Broader contacts were normal at T1 and T2 in the posterior segments. At T2, changes in the interproximal contacts were observed in the posterior segments, and substantial evidence was available, particularly for the mandibular arch.

A preliminary investigation into the impact of soft tissue augmentation-based periodontal phenotype modification therapy for patients exhibiting class III decompensation.

BACKGROUND: Patients with skeletal angle Class III malocclusion usually have inadequate hard and soft tissue volume at the mandibular anterior teeth. The labial proclination at the teeth may lead to gingival recession. The purpose of this study was to explore whether periodontal phenotype modification therapy with soft tissue augmentation (PhMT-s) can prevent gingival recession in these patients. METHODS: Four patients with skeletal Class III malocclusion and a thin periodontal phenotype underwent surgical-orthodontic treatment. Prior to tooth movement, they underwent a minimally invasive vestibular incision with subperiosteal tunnel access combined with autogenous connective tissue grafts for periodontal phenotype modification with soft tissue augmentation (PhMT-s). The labial gingival thickness of the anterior mandibular teeth was measured at three distinct levels: at the cementoenamel junction (GT0), 3 mm apical to the CEJ (GT3), and 6 mm apical to the CEJ (GT6). These measurements were taken at baseline, three months following PhMT-s, and after tooth decompensation. Additionally, a biopsy sample was obtained from the PhMT-s site of one patient. All sections were subsequently stained using hematoxylin and eosin, Masson trichrome, Sirius Red, and immunohistochemistry. RESULTS: The thickness of the labial gingiva was increased about 0.42 to 2.00 mm after PhMT-s. At the end of pre-orthognathic surgical orthodontic treatment, the thickness of the labial gingiva was increased about - 0.14 to 1.32 mm compared to the baseline and no gingival recession occurred after the pre-orthognathic surgical orthodontic treatment. The histologic results demonstrated that the grafts obtained from the PhMT-s site exhibited increased deposition of collagen fibers. Moreover, the proportion of type III collagen increased and the grafts displayed significantly reduced positive expression of CD31 and OCN. CONCLUSIONS: PhMT-s increased the thickness of the soft tissue, stabilizing the gingival margin for teeth exhibiting a thin periodontal phenotype and undergoing labial movement. This is attributed to the increased deposition of collagen fibers.

Reverse chewing patterns in patients with bilateral posterior crossbite are related to the occlusal features of the malocclusion.

BACKGROUND: Bilateral posterior crossbite (BPXB) is a severe malocclusion associated with maxillary hypoplasia. BPXB may involve the same or a different number of teeth between the sides. OBJECTIVES: To evaluate the masticatory function in BPXB and the association between the masticatory alterations and the occlusal features of BPXB. METHODS: This observational study included 170 participants: 130 patients with BPXB (65 occlusally symmetric BPXB, i.e. same number and type of posterior teeth in crossbite between the sides, F = 33, M = 32, median age 9.6 (8.2-13) [years.months]; 65 patients occlusally asymmetric BPXB, F = 30, M = 35, median age 9.9 (8.3-13.6)) and 40 controls (F = 25, M = 15, median age 10.2 (9.4-11.6)). The masticatory function was evaluated by the detection of the Reverse Chewing Cycles (RCCs) recorded with a kinesiograph using standardised soft and hard boluses. RESULTS: The frequency of RCCs was significantly increased in all BPXB patients compared to controls (p < .000). In symmetric BPXB patients, there were no significant differences in the frequency of RCCs during chewing on the left or the right side. In asymmetric BPXB patients, the frequency of RCCs was significantly increased during chewing on the side with relatively more teeth in crossbite (p < .000). CONCLUSIONS: The masticatory function was significantly altered in all BPXB patients and it was differently affected by symmetric or asymmetric occlusal features of the malocclusion.

Evaluation of palate morphology in patients treated with leaf expander and hyrax expander: A geometric morphometric analysis.

OBJECTIVE: The aim of this study was to evaluate changes in shape of the palatal vault after maxillary expansion with hyrax expander (HE) and leaf expander (LE), using 3D Geometric Morphometric Analysis. SETTING AND SAMPLE POPULATION: Overall, 250 patients (110 M, 140 F) with maxillary transverse deficiency were selected for this study. In this study, 127 subjects were treated with HE, 123 with LE. MATERIALS AND METHODS: Digital dental models were obtained pre-treatment (T0) and after 12 months from the cementation of the device (T1) and processed by means of a digital scanner. Linear and morphometric analyses were conducted to determine the effects of each appliance on dental measurements and palatal shape, and a multiple linear regression was performed to analyse the influence of anchorage and appliance type on final shape. RESULTS: Morphometric analysis showed that there was a lowering of the palatal vault in the HE group, while in the LE group it remained unchanged: the difference in palatal shape at time T0 and T1 was statistically significant in both treatments (HE vs. LE). In the HE group, the change in shape also included the upper part of the palatal vault in the vertical dimension, while in the LE group the change in shape interested mainly palatal shelves and the lower portion of the palate. CONCLUSIONS: Both LE and HE produce clinically significant changes in the morphology of the palatal vault.

Comparative assessment of the clinical outcomes of clear aligners compared to fixed appliance in class II malocclusion.

OBJECTIVE: This study compared clinical outcomes between aligners and fixed appliances in class II adolescent patients. MATERIALS AND METHODS: Records of 31 aligners and 35 fixed class II patients, aged 13.5 ± 1.6 years were compared. Class II elastics was the mechanism employed for correcting the malocclusion. DI scores were used to compare initial complexity, and the PAR index scores were used to compare the clinical outcomes. Data on demographics, treatment and finishing durations, number of visits and refinements, duration of class II correction, and changes in the IMPA were collected. RESULTS: The mean pre-, post-treatment, and overall reduction in PAR index scores between the groups were not significantly different (P > 0.05). The clear aligners group had significantly shorter treatment duration (20.0 ± 11.6 months) than the fixed group (27.4 ± 9.1 months) (P < 0.001). The number of visits for the aligners' group was significantly less (12.7 ± 6.2) than in the fixed group (17.8 ± 5.8) (P < 0.001). Duration for class II correction was significantly shorter for clear aligners (13.3 ± 10.0 months) compared to the fixed group (17.4 ± 9.0 months) (P = 0.026). A smaller post-treatment change in IMPA (2 ± 6°) was detected in the aligners group compared to the fixed group (5 ± 6°) (P < 0.05). CONCLUSIONS: Treatment outcomes for aligners in class II adolescent patients were comparable to those achieved in fixed appliances. Shorter treatment and class II correction durations, fewer visits, and better control for the IMPA were noticed in the aligners' group. CLINICAL RELEVANCE: Treating class II adolescent patients with aligners seems promising and demands shorter treatment time and fewer visits.

A nomogram prediction of gingival recession in mandibular incisors of orthodontic-orthognathic treated skeletal class III malocclusion with or without PAOO: A retrospective cohort study.

Background: To assess the alterations in gingival thickness and the occurrence gingival recession subsequent to orthodontic-orthognathic treatment of mandibular incisors in skeletal Class III and identify risk factors associated with gingival recession. Methods: In this retrospective cohort study, we enrolled 33 patients exhibiting skeletal Class III malocclusion, totaling 131 mandibular incisors, who were undergoing orthodontic- orthognathic treatment that did not involve extraction of mandibular teeth. The subjects were categorized into surgery group (S; n = 17; ANB = -5.55 ± 3.26; IOFTN = 4.60 ± 0.51, scores ranging: 4.3-5.3) and non-surgery group (NS; n = 16; ANB = -3.00 ± 4.08; IOFTN = 4.63 ± 0.50, scores ranging: 4.3-5.4), based on if they had history of Periodontally Accelerated Osteogenic Orthodontics surgery (S) or not (NS). Patients in S group received orthognathic surgery about 1-1.5 years after Periodontally Accelerated Osteogenic Orthodontics surgery. Alterations in gingival thickness, gingival recession, and keratinized gingival width were compared before and after orthodontic-orthognathic treatment. Logistic regression analysis was used to construct a gingival recession prediction model and draw nomograms. Results: After orthodontic-orthognathic treatment, the gingival thickness and keratinized gingival width in NS group decreased by 0.15 ± 0.21 mm and 0.74 ± 0.91 mm, whereas those in the S group increased by 0.32 ± 0.28 mm and 2.09 ± 1.51 mm (P < 0.05). After orthodontic-orthognathic, the percentage of gingival recession increased by 47.62 % in NS group, which was 14.77 times that of S group (P < 0.05). Multivariate regression analysis indicated that skeletal Class III patients with a gingival thickness below 0.72 mm, an alveolar bone height exceeding 2.36 mm, and an alveolar bone thickness under 0.45 mm might be at elevated risk for developing gingival recession following orthodontic - orthognathic therapy. Conclusions: Drawing on the findings of our investigation, we concluded the risk of gingival recession of mandibular anterior teeth increased after orthodontic-orthognathic treatment in skeletal Class III, whereas Periodontally Accelerated Osteogenic Orthodontics surgery could significantly improve the periodontal phenotype and prevent gingival recession.

Clinical effects of twin-block combined with maxillary expansion on the upper airway in adolescents with Class II malocclusion.

BACKGROUND: Class II malocclusion, particularly class II division 1, poses a significant orthodontic challenge with implications for both aesthetics and health. This study aimed to explore the impact of twin-block (TB) combined with maxillary expansion treatment (TB-ME) on upper airway dimensions and inflammatory profiles in adolescents with skeletal Class II Division 1 malocclusion in adolescent. METHODS: Ninety-two eligible patients were randomly assigned to two groups: TB-ME treatment and traditional McLaughlin Bennett Trevisi (MBT) straight-wire orthodontic treatment (Control). Cephalometric lateral X-ray scans were conducted before and after treatment to assess skeletal changes, including SNA, ANB, and SNB angles, which are essential to assess the anteroposterior relationships of the maxilla and mandible to the cranial base. We also measured the upper airway volumes and areas. Concentrations of inflammatory factors including intercellular adhesion molecule 1 (ICAM-1), matrix metallopeptidase 2 (MMP2), and interleukin 8 (IL-8) of gingival crevicular fluid analysis (GCF) were detected by enzyme-linked immunosorbent assay. RESULTS: TB-ME treatment induced significant improvement in cephalometric parameters, including a decrease in SNA and ANB angles and an increase in SNB angle. Upper airway volumes and areas increased significantly in both groups, with TB-ME showing greater improvements. GCF analysis revealed a reduction in ICAM-1, MMP2, and IL-8 concentrations in the TB-ME group compared to the Control group. CONCLUSIONS: TB-ME treatment demonstrates multifaceted improvements in skeletal malocclusion, upper airway dimensions, and inflammatory profiles in adolescents with class II division 1 malocclusion, showing the promise of TB-ME in addressing the complexities associated with class II malocclusion.

Evaluation of the bioelectrical activity of the masticatory muscles in patients with narrowed maxillary transverse dimension compared to the occlusal norm.

OBJECTIVE: The aim of the study was to determine how the electrical activity of the temporalis, masseter and sternocleidomastoid muscles differs in children with reduced transverse jaw dimension compared to children with normal occlusion. DESIGN: It was a experimental study. Thirty-seven patients were included in the study. 18 in the study group received orthodontic treatment with removable appliances and 19 subjects were classified as normal occlusion subjects in the control group. A panoramic X-ray and digital intraoral scan were taken, followed by an surface electromyography of three muscle pairs (temporalis muscles, masseter muscles, sternocleidomastoid muscles) in resting position, while clenching and clenching on cotton rollers. RESULTS: There was significantly greater activity in the experimental group than in the control group comparing muscles: temporalis muscles and masseter muscles in the resting position. Additionally, significantly greater activity of muscles in the control group was found during clenching. However, the asymmetry index of muscles indicates that there is significantly greater asymmetry of muscles activity in the experimental group. Compared to children with normal occlusion, children with a narrowed transverse dimension of the jaw have statistically significant differences in the bioelectrical activity of the temporalis, masseter and sternocleidomastoid muscles, as well as greater asymmetry in the bioelectrical voltage of the masseter muscles. CONCLUSIONS: Patients with reduced transverse dimension of the jaw are characterized by increased resting activity of the masticatory muscles and reduced functional activity of the masticatory muscles. These patients have increased asymmetry in the bioelectrical tension of the masticatory muscles.

Prevalence of malocclusions and parafunctional habits in pediatric patients with developmental dyslexia.

Objective: The study aimed to assess the prevalence of dental malocclusion, orthodontic parameters, and parafunctional habits in children with developmental dyslexia (DD). Methods: Forty pediatric patients (67.5% boys and 32.5% girls, mean age: 11.02 ± 2.53 years, range: 6-15 years) with DD were compared with 40 age- and sex-matched healthy participants for prevalence of dental malocclusion, orthodontic parameters, and parafunctional habits. Dental examinations were performed by an orthodontist. Results: Pediatric patients with DD exhibited a significantly higher prevalence of Angle Class III malocclusion (22.5% vs. 5.0%, P = 0.024), deep bite (27.5% vs. 7.5%, P = 0.019), midline deviation (55.0% vs. 7.5%, P < 0.0001), midline diastemas (32.5% vs. 7.5%, P = 0.010), wear facets (92.5% vs. 15.0%, P < 0.0001), self-reported nocturnal teeth grinding (82.5% vs. 7.5%, P < 0.0001), nail biting (35.0% vs. 0.0%, P < 0.0001), and atypical swallowing (85.0% vs. 17.5%, P < 0.0001) compared to that in healthy controls. Conclusions: Pediatric patients with DD showed a higher prevalence of Class III malocclusion, greater orthodontic vertical and transverse discrepancies, and incidence of parafunctional activities. Clinicians and dentists should be aware of the vulnerability of children with dyslexia for exhibiting malocclusion and encourage early assessment and multidisciplinary intervention.

Clinical Management of Facemasks for Early Treatment of Class III Malocclusion: A Survey among SIDO Members.

To evaluate whether there are differences among orthodontists in the clinical management of facemask treatment for early treatment of Class III malocclusion, a survey consisting of 16 questions was conducted among members of the Italian Society of Orthodontics (SIDO). Sixty percent of the respondents were Specialists in Orthodontics (S) whereas 40% were General Dentists practicing Orthodontics (GD). Descriptive statistics were calculated to summarize the collected data. Differences in answers between S and GD were assessed with the Fisher's exact test for dichotomous variables, chi-square test for qualitative variables, and Mann-Whitney test for ordinal variables. A total of 151 clinicians participated in this survey. As for treatment timing, about 80% of the participants reported treating Class III patients with RPE and facemask between 5 and 8 years of age. Most of the participants requested the patients to wear the facemask in the afternoon and at night for a period of 9 or 12 months with recommended forces of 500 g per side. Comparisons between S and GD showed that S preferred the Petit facemask whereas GD favored the Delaire's type facemask (Fisher's Exact test, p = 0.0005). S and GD also differed significantly in their judgment of the most critical time of treatment, which for the majority of GD was the initial period but for the S was the final period (Chi-square test p = 0.0188). This survey showed that the facemask is not well received by the patients who, along with their parents, express concerns regarding its tolerability.

The Role of Malocclusion and Oral Parafunctions in Predicting Signs and Symptoms of Temporomandibular Disorders-A Cross-Sectional Study.

BACKGROUND: The aim of this study was to examine to what extent malocclusion and parafunctional habits contribute to the development of signs and symptoms associated with temporomandibular disorders (TMD) in schoolchildren with mixed dentition in Croatia in a sample of 338 children, aged 9 to 15 years. METHODS: TMD signs and symptoms assessed by the clinician were joint function and pain, masticatory muscles tenderness, range of mandibular motion, and joint sounds. To evaluate subjective symptoms and parafunctions, children and parents were asked about the presence of headaches, jaw locking, temporomandibular joint (TMJ) sounds, pain during mouth opening, or bruxism, as well as parafunctions like biting pencils or nails, chewing hard candies or ice, daily gum chewing, opening bottles with teeth, engaging in jaw play, thumb-sucking, and clenching/grinding teeth. RESULTS: At least one symptom of a TMD was pronounced in 142 participants (42.0%). The most commonly reported parafunction was pencil or nail biting, present in 25.1% of participants. Class II malocclusion increased the likelihood by 2.6 times, pencil or nail biting by 2.34 times, and clenching/grinding teeth by 8.9 times that the subject would exhibit at least one TMD symptom. CONCLUSIONS: Every child with mixed dentition should undergo a brief examination of the TMJ, especially in cases of Class II malocclusion, pencil or nail biting, and teeth clenching or grinding, as these have all been identified as significant risk factors that increase the likelihood of experiencing TMD symptoms. This highlights the need for proactive screening and assessment by healthcare providers to reduce the risk and prevalence of TMDs in affected children and ensure timely diagnosis and treatment.

Differential outcomes of jaw bone position after surgical-orthodontic treatment in three types of skeletal Class III asymmetry patients.

BACKGROUND/PURPOSE: Facial asymmetry is common in Class III patients requiring orthognathic surgery. This study aimed to analyze jaw bone position after surgical-orthodontic treatment in three types of skeletal Class III asymmetry patients. METHODS: The retrospective study included 30 Class III patients who underwent surgical-orthodontic treatment comprising LeFort I osteotomy and bilateral sagittal split osteotomy (BSSO) without genioplasty. Cone-beam computed tomography (CBCT) images obtained before surgery (T1) and after post-surgical orthodontic treatment (T2) were superimposed with voxel-based registration. Patients were classified into three groups based on T1 CBCT scans. Groups 1 and 2 exhibited menton and ramus deviated to the same side. Menton deviation was larger than ramus width asymmetry in group 1, while the reverse was true for group 2. Group 3 had menton deviation contralateral to the side with greater ramus width. RESULTS: Menton deviation after treatment was improved in all groups. Ramus width asymmetry and coronal ramus angle difference decreased in groups 1 and 2. Neither improvement nor deterioration of ramus width asymmetry was noted for group 3. Comparing to groups 1 and 2, group 3 had greater roll and yaw rotations of distal segment, more upward pitch of proximal segment on chin deviation side, and largest inward yaw as well as backward translation of proximal segment on non-deviation side. CONCLUSION: The positional changes of osteotomy segments differed among three types of mandibular asymmetry. Special attention should be given to the atypical mandibular asymmetry with mandibular body and ramus deviating to opposite directions during surgical correction of jaw deflection.

Ponticulus posticus and skeletal malocclusion: A pilot study in a Southern Italian pre-orthodontic court.

Purpose: Ponticulus posticus (PP) is a bony protrusion located between the posterior portion of the superior articular process and the posterolateral portion of a posterior arch of the atlas vertebrae in the cervical spine. The aim of this study is to verify the presence of different types of PP in a Southern Italian pre-orthodontic cohort to understand its correlation with skeletal class and maturity. Methods: A case-control retrospective study was conducted, utilizing 212 latero-lateral telecranium radiographs to analyze skeletal maturity according to the cervical vertebral maturation method, the Angle's classification of malocclusion (I, II, or III), and the presence or absence of the PP, whether complete (c-PP) or partial (p-PP). A total of 212 lateral cephalograms were analyzed. Results: Of the 72 male patients, 67 (93%) exhibited PP, and 116 (88%) were PP. The chi-square value was 0.001, while Cramer's V was 0.270, indicating a significant correlation between age groups and PP presence, and a very strong association overall. Out of the 41 complete PP cases, class I was notably more prevalent than classes II and III. Conclusion: Orthodontists should carefully consider PP when assessing and treating individuals with or without skeletal discrepancies and dental anomalies.

Genetic change investigation in DOCK1 gene in an Iranian family with sign and symptoms of temporomandibular joint disorder (TMD).

OBJECTIVES: Temporomandibular joint disorder (TMD) is a complex condition with pain and dysfunction in the temporomandibular joint and related muscles. Scientific evidence indicates both genetic and environmental factors play a crucial role in TMD. In this study, we aimed to discover the genetic changes in individuals from 4 generations of an Iranian family with signs and symptoms of TMD and malocclusion Class III. MATERIALS AND METHODS: Whole Exome Sequencing (WES) was performed in 4 patients (IV-8, IV-9, V-4, and V-6) with TMD according to (DC/TMD), along with skeletal Class III malocclusion. Then, PCR sequencing was performed on 23 family members to confirm the WES. RESULTS: In the present study, WES results analysis detected 6 heterozygous non-synonymous Single Nucleotide Variants (SNVs) in 5 genes, including CRLF3, DNAH17, DOCK1, SEPT9, and VWDE. A heterozygous variant, c.2012T > A (p.F671Y), in Exon 20 of the DOCK1 (NM_001290223.2) gene was identified. Then, this variant was investigated in 19 other members of the same family. PCR-Sequencing results showed that 7/19 had heterozygous TA genotype, all of whom were accompanied by malocclusion and TMD symptoms and 12/19 individuals had homozygous TT genotype, 9 of whom had no temporomandibular joint problems or malocclusion. The remaining 3 showed mild TMD clinical symptoms. The 5 other non-synonymous SNVs of CRLF3, DNAH17, SEPT9, and VWDE were not considered plausible candidates for TMD. CONCLUSIONS: The present study identified a heterozygous nonsynonymous c.2012T > A (p.F671Y) variant of the DOCK1 gene is significantly associated with skeletal class III malocclusion, TMD, and its severity in affected individuals in the Iranian pedigree. CLINICAL RELEVANCE: The role of genetic factors in the development of TMD has been described. The present study identified a nonsynonymous variant of the DOCK1 gene as a candidate for TMD and skeletal class III malocclusion in affected individuals in the Iranian pedigree.

Prevalence of Malocclusion Traits in Primary Dentition, 2010-2024: A Systematic Review.

The present review was aimed to describe the prevalence and the regional distribution of malocclusion among preschool children worldwide. Two independent reviewers performed a systematic literature search to identify English publications from January 2010 to May 2024 using PubMed, ISI Web of Science and Embase. Search MeSH key words were "malocclusion", "primary dentition" and "child, preschool". The reporting quality was assessed by the modified Newcastle-Ottawa Quality Assessment Scale. We identified 2599 publications and recruited 47 articles. Fourteen of the included studies were conducted in Asia, four in Europe, twenty-eight in South America and one in Africa. The prevalence of malocclusion ranged from 28.4% to 83.9%, and half of the reported prevalences were higher than 50%. The highest percentage was in Asia (61.81%), followed by Europe (61.50%), South America (52.69%) and Africa (32.50%). Statistically significant differences existed in deep overbite, anterior open bite, posterior crossbite, edge-to-edge incisor relationship and distal step between continents (p < 0.05). Europe showed the highest prevalence (33.08%) of deep overbite. Africa showed the highest prevalence (18.60%) of anterior open bite. Europe showed the highest prevalence (15.38%) of posterior crossbite. The most common malocclusion traits were increased overjet and deep overbite. To conclude, malocclusion remained prevalent in the primary dentition and varied between countries.

Predicting Outcome in Clear Aligner Treatment: A Machine Learning Analysis.

Background/Objectives: Machine learning (ML) models predicting the risk of refinement (i.e., a subsequent course of treatment being necessary) in clear aligner therapy (CAT) were developed and evaluated. Methods: An anonymized sample of 9942 CAT patients (70.6% females, 29.4% males, age range 18-64 years, median 30.5 years), as provided by DrSmile, a large European CAT provider based in Berlin, Germany, was used. Three different ML methods were employed: (1) logistic regression with L1 regularization, (2) extreme gradient boosting (XGBoost), and (3) support vector classification with a radial basis function kernel. In total, 74 factors were selected as predictors for these methods and are consistent with clinical reasoning. Results: On a held-out test set with a true-positive rate of 0.58, the logistic regression model has an area under the ROC curve (AUC) of 0.67, an average precision (AP) of 0.73, and Brier loss of 0.22; the XGBoost model has an AUC of 0.67, an AP of 0.74, and Brier loss of 0.22; and the support vector model has a recall of 0.61 and a precision of 0.64. The logistic regression and XGBoost models identify predictors influencing refinement risk, including patient compliance, interproximal enamel reduction (IPR) and certain planned tooth movements, for example, lingual translation of maxillary incisors being associated with the lowest risk of refinement and rotation of mandibular incisors with the highest risk. Conclusions: These findings suggest moderate, well-calibrated predictive accuracy with both regularized logistic regression and XGBoost and underscore the influence the identified factors have on the risk of refinement in CAT, emphasizing their importance in the careful planning of orthodontic treatment and the potential for shorter treatment times, less patient discomfort, and fewer clinic visits. Identification of at-risk individuals could support tailored clinical decision-making and enable targeted interventions.

Assessment of the Relationship between Antero-Posterior Dental Malocclusions, Body Posture Abnormalities and Selected Static Foot Parameters in Adults.

Objectives: This study aimed to find if a relationship exists between antero-posterior malocclusions and the level of musculoskeletal disorders in adults, including body posture and static foot analysis. Methods: In all, 420 participants were recruited through convenience sampling (Kraków University students and patients of a local dentist's practice). Following general medical interviews, dental examinations and consideration of inclusion and exclusion criteria, 90 healthy volunteers (ages 19-35) were enrolled and assigned to three groups (n = 30) based on occlusion type (Angle's molar Class I, II or III). The research procedure involved occlusion and temporomandibular disorder assessment conducted by a dental specialist. Comprehensive morphological measurements of body asymmetry were performed using the Videography 2D package and FreeSTEP software, which calculated the parameters determined from anterior, posterior and lateral projection photos. Foot loading distribution was analyzed using the FreeMED baropodometric platform. Results: Significant differences were demonstrated in the positioning of the head, cervical and lumbar spine in the sagittal plane among individuals with the analyzed occlusal classes (p < 0.05). Individuals with Angle's Class II exhibited significantly greater forward head positions and greater depths of cervical and lumbar lordosis compared with individuals with Class III or Class I. Those with overbites had higher forefoot loading. The Class III individuals exhibited greater L-R displacement, indicating a larger angle of displacement of the centers of the right and left feet relative to the lower edge of the measurement platform, suggesting pelvic rotation. Conclusions: An inclination for concurrent occurrences of malocclusions and posture deviations in the sagittal plane was observed. An interdisciplinary approach involving dentistry and physiotherapy specialists which utilizes tools for comprehensive posture assessment is crucial for diagnosing and treating such conditions.

Comparison of Speech Defects in Different Types of Malocclusion.

Introduction Speech has a great impact on human evolution, allowing for the widespread knowledge and advancement of tools. Difficulty in pronouncing one or more sounds is the most common speech impairment. Speech defects are more commonly associated with class III malocclusion patients (difficulty in pronouncing 's' and 't' sounds), the second in line is class II malocclusion (difficulty in pronouncing 's' and 'z' sounds), and speech distortions are least affected in class I malocclusion (difficulty in pronouncing 's' and 'Sh'). Most patients with dentofacial disharmonies and speech distortions need orthodontic care and orthognathic surgery to resolve their issues with mastication, aesthetics, and speech. Aims and objectives To compare and assess speech difficulties in different types of malocclusion. Materials and methods The study was conducted over 160 subjects for three and half months. All of them were evaluated for speech defects before they received orthodontic treatment. The main basis of this study is according to Angle's classification of malocclusion. The subjects were segregated according to Angle's classification of malocclusion. Malocclusion traits that are included in this study are Angle's class I, Angle's class II division I and division II, and Angle's class III. Results According to the results, out of 160 subjects, labio-dental speech defects are observed in 8% where n=13 of the study participants, linguodental speech defects are observed in 2% where n=3, lingua-alveolar speech defects are present in 54% where n=86, and bilabial speech defects are observed in 2% where n=3 of the study participants. Here 'n' represents the frequency of the subjects. Severe speech defects are seen in Angle's class III malocclusion. Results according to the type of malocclusion include: labio-dental speech defects are seen in 37.5% in class I, 25% in class II division I, 0% in class II division II, and 37.5% in class III. Linguodental speech defects are seen in class III malocclusion subjects only. Lingua-alveolar sounds are seen in 27.8% of class I, 29.6% of class II division I, 1.9% of class II division II, and 40.7% of class III. Bilabial speech defects are only seen in class II division I subjects. According to the results, only lingua-alveolar speech defects are statistically significant, and more severe speech defects were observed in class III malocclusion. Conclusion Speech plays an important role in affecting the quality of life of people. Different types of malocclusion traits are associated with different types of speech defects.

Non-extraction Approach in a Borderline Case of a Growing Patient: A Case Report.

This case presents the effective non-extraction orthodontic treatment of a 13-year-old boy with crowding in both upper and lower arches and deep bite. The patient's chief complaint was irregularly placed maxillary anterior teeth. The active treatment duration lasted for 10 months, which resulted in the successful alleviation of arch crowding and correction of the deep bite without the extraction of any sound erupted tooth. Posttreatment, all of the patient's chief complaints were relieved. Essix retainers were fitted post-debonding, with instructions for the patient to wear them for the subsequent year to maintain the achieved results. This case highlights the efficacy of non-extraction orthodontic strategies in addressing crowding and deep bite issues, drawing the importance of individualized treatment plans to achieve optimal outcomes.

Evaluation of Sella Turcica Variations in Lateral Cephalometric Radiographs and its Association with Malocclusion.

Objectives: Understanding the shape and size of the sella turcica may help predict future orthodontic treatment needs related to skeletal malocclusion. This study aims to assess different morphological types of the sella turcica in lateral cephalometric radiographs and its correlation with malocclusion, as well as the relationship between gender and linear measurements of sella turcica. Materials and Methods: The lateral cephalometric radiographs of 410 volunteers (111 men and 299 women) aged 8 to 30 years were evaluated. The patients were divided into three groups based on their skeletal growth patterns (cl I, II, and III). Then the anatomical shape and linear dimensions of sella turcica were assessed. Measurements were made using Adobe Photoshop Version: 20.0.0 software, and data analysis was performed by IBM SPSS Statistics version 25. Results: The following morphologies were observed: normal (37.8%), oblique anterior wall (9.3%), double contour of the floor (21.5%), sella turcica bridge (8.8%), irregularity (notching) in the posterior part of sella turcica (16.6%), and pyramidal shape of the dorsum sellae (6.1%). No statistically significant relationship was found between sella turcica variations and skeletal malocclusion. The correlation between female sex with the diameter (p=0.027) and depth values (p=0.035) of sella turcica was statistically significant. There was no statistically significant difference (p>0.05) in length based on gender. Conclusion: The most morphological type reported was normal sella turcica (37.8%). Anatomical variations of sella turcica had no association with malocclusion. The most considerable depth and diameter of sella turcica were found in women.