Skeletal Pattern Research Articles

Use of cone-beam computed tomography for investigation of factors affecting the failure of temporary anchorage devices.

To assess the reasons behind the failure of temporary anchorage devices (TADs) installed in the buccal alveolar zone between the maxillary second premolars and the first molars. Sixty patients (11 male, 49 female, mean age 21 years) were included. Logistic regression analysis was performed to determine the influence of the following factors on the presence or absence of TAD failure: sex, age, sagittal and vertical skeletal patterns, root contact, bone density, bone contact length, and presence of maxillary sinus perforation. Fisher's exact test was performed to evaluate differences in failure rate between tooth types for teeth in contact with TADs (second premolar or first molar). Measurements were obtained using lateral cephalograms at the initial visit and data obtained by cone-beam computed tomography (CBCT) before and after TAD implantation. Logistic regression analysis showed that only root contact was associated with TAD failure; there was no association between the type of tooth in contact with the TAD and failure. Root contact with a TAD significantly influenced TAD failure. Therefore, preliminary examination using three-dimensional (3D) evaluation with CBCT is essential to ensure that the TAD is not placed near the root of the tooth.

Evaluation of the infrazygomatic crest and mandibular buccal shelf in different sagittal skeletal patterns: a cone-beam computed tomography study

Abstract Objectives To compare bone thickness, bone height, and density in the infrazygomatic crest (IZC) and the mandibular buccal shelf (MBS) associated with different sagittal skeletal patterns. Material and Methods This retrospective study included three groups of which a Class I group consisted of 28 patients (24 female, 4 male, mean age: 26.46 ± 6.1), a Class II group comprised 31 patients (28 female, 3 male, mean age: 30.08 ± 5.9), and a Class III group included 26 patients (22 female, 4 male, mean age: 26.21 ± 5.3). Evaluations of bone characteristics were performed for both the IZC and MBS using cone-beam computed tomography (CBCT). Maxillary length and mandibular body length were also measured on lateral cephalograms. One-way ANOVA, chi-squared, and Spearman’s correlation tests were applied for statistical analysis. Results The Class II group showed significantly greater bone thickness at the distal root level of the maxillary second molar in IZC (p < 0.05). While bone thickness showed no statistically significant difference in the MBS between the groups (p > 0.05), the Class II group showed significantly higher bone height values at the distal root level of the mandibular second molar in the MBS (p < 0.05). A statistically significant increase from the mesial aspect to the distal aspect was observed in total bone thickness in the Class I group and total bone thickness and height in the Class II and III groups in the MBS. The mandibular body length and SNB values were positively correlated with the total bone thickness and bone height of the MBS. Conclusions Bone thickness in the IZC and bone density in both the IZC and MBS were similar in the different sagittal skeletal patterns. Total bone thickness in the Class I and III groups and the total bone height in the Class II group showed a gradual increase from the mesial to the distal in the MBS. The length of the mandibular body may be a clinical clue to assist in the selection of the appropriate implantation area.

The relationship between third molar agenesis and craniofacial morphology: a systematic review and meta-analysis.

Agenesis of third molar agenesis has a higher incidence than other tooth development anomalies. Previous research identified a potential correlation between third molar agenesis and specific craniofacial morphology; however, no systematic review and meta-analysis on this topic currently exists. The objective of this systematic review and meta-analysis was to evaluate the association between third molar agenesis and craniofacial sagittal and vertical morphology. An electronic search was conducted on PubMed, Embase, Web of Science, and the Cochrane Library without restrictions on publication year or language; this was supplemented by the manual retrieval of relevant literature. Cross-sectional studies that compared craniofacial morphology using angular and linear measurements obtained from lateral cephalography between patients with third molar agenesis and those without were included. The quality assessment of the enrolled articles was evaluated by the Joanna Briggs Institute critical appraisal tool. Meta-analysis and sensitivity analysis were performed by Review Manager software (The Cochrane Collaborative, version 5.4, Cochrane IMS). A total of seven studies were included. Meta-analysis demonstrated that the ANB (mean differences (MD) = -0.75, 95% CI: -1.31 to -0.19, P < 0.01), palate length (ANS-PNS, MD = -1.68, 95% CI: -2.24 to -1.11, P < 0.01), and mandibular length (Go-Pog, MD = -0.36, 95% CI: -0.59 to -0.13, P < 0.01) were smaller in patients with third molar agenesis. With regard to vertical craniofacial morphology, the mandibular plane angle (MP-FH; MD = -1.88, 95% CI: -3.45 to -0.31, P = 0.02), gonial angle (gonial angle; MD = -1.73, 95% CI: -2.69 to -0.77, P < 0.01) and lower face height (lower face heigh angle; MD = -1.36, 95% CI: -1.94 to -0.77, P < 0.01) were smaller in patients with third molar agenesis, indicating a flatter or brachyfacial skeletal pattern. The results of this study suggest that third molar agenesis maybe associated with a reduced maxillary length and a flatter mandible. However, these findings need to be interpreted with caution due to inconsistencies in the certainty of evidence. PROSPERO (CRD42023448226).

Prevalence of condylar morphological changes in individuals with class II malocclusion.

This observational, cross-sectional study with retrospective collection was aimed to evaluate the prevalence of morphological changes in mandibular condyles in individuals with class II malocclusion, classified according to different vertical growth patterns (brachyfacial, mesofacial, and dolichofacial), through cone beam computed tomography (CBCT). Seventy CBCT images (140 mandibular condyles) were selected from individuals without orthodontic treatment, of both sexes, aged between 25 and 50 years. No statistically significant differences were found between facial patterns; however, there was a higher relative prevalence of bone changes in dolichofacial individuals with flattening (62%), sclerosis (44%), and subchondral bone cyst (20%). Erosion and osteophytes prevailed in mesofacial (39%), and brachyfacial individuals (32%), respectively. Thus, there was no statistically significant difference in the prevalence of degenerative changes between the vertical skeletal patterns. Flattening was the most prevalent change, whereas subchondral bone cyst was the least prevalent among the three groups studied. The observational design of this study makes it possible to analyze image banks to verify the correlation of morphological changes in the temporomandibular joint in different facial patterns in patients with class II malocclusion. A limitation of the study is that clinical characteristics were not evaluated.

Multidimensional tooth movement boundaries in the extended aesthetic zone: a cone-beam computed tomography study

Abstract Purpose To establish tooth movement boundaries in four directions by a novel morphometric analysis of alveolar bone using conebeam computed tomography (CBCT) images. The aim was to assist clinicians in minimising the occurrence of bone fenestration and dehiscence, thereby facilitating safe and efficient orthodontic treatment. Methods CBCT images of 123 male volunteers comprising 55 individuals with hypodivergent vertical skeletal patterns and 68 individuals with normodivergent vertical skeletal patterns and normal occlusions but without a history of previous orthodontic treatment, were analysed. The mesiodistal and labiolingual alveolar bone height (ABH) as well as the labiolingual cancellous bone thickness (CBT) were measured in relation to the maxillary and mandibular anterior teeth and premolars. These parameters were subsequently compared between the different vertical skeletal patterns. Results Teeth within the extended aesthetic zone exhibited a limited range of safe movement on the labial aspect across all three root aspects, with 97.6% of the upper lateral incisors and 98.4% of the lower lateral incisors positioned against the labial cortical plate (&lt;0.5 mm). The lingual aspects had significantly more space for tooth movement compared with the labial aspects (P &lt; 0.05). The ABH was significantly greater in the hypodivergent group than the normodivergent group involving particular teeth and sites in the maxilla (P &lt; 0.05), while no significant difference was noted in the mandible. The hypodivergent group also exhibited thicker cancellous bone on most labial and some lingual aspects. Conclusions The findings provided the average tooth movement range in the horizontal and vertical directions within the extended aesthetic zone in male individuals presenting with a normal occlusion. It was concluded that a hypodivergent growth pattern may have a relatively large range of safe tooth movement in the sagittal and vertical directions.

Growth changes in the craniofacial complex in class II skeletal patterns and cervical vertebral maturation: A cross-sectional study

Growth changes in the craniofacial complex in class II skeletal patterns and cervical vertebral maturation: A cross-sectional study

Adults with Treacher Collins Syndrome Share Comparable 3D Upper Airway Dimensions with Nonsyndromic Individuals.

Sleep apnea symptoms, such as snoring and daytime somnolence, are commonly observed in individuals with Treacher Collins Syndrome (TCS) and may be related to airway obstruction due to micro- and retro-gnathia. This study aims to three-dimensionally evaluate the upper airway using cone-beam computed tomography (CBCT) exams of adolescents (TCS-ADOL) and adults (TCS-ADUL) with TCS compared to a nonsyndromic group (CON). Twenty-six CBCT exams were divided into three groups: TCS-ADOL (n = 7) (13.14 ± 1.67 years): CBCT exams of TCS adolescents; TCS-ADUL (n = 10) (21.80 ± 4.39 years): CBCT exams of TCS adults; and CON (n = 9) (25.33 ± 8.57 years): CBCT exams of adult nonsyndromic individuals with Class II skeletal pattern. The variables analyzed were (1) total upper airway volume; (2) nasal cavity volume; (3) total pharyngeal volume; (4) nasopharyngeal volume; (5) oropharyngeal volume; (6) pharyngeal minimal cross-sectional area; (7) pharyngeal length; and (8) pharyngeal depth. Scans were analyzed by two examiners, and intra- and inter-rater agreement was calculated. A p-value of ≤0.05 was considered significant. Although not statistically significant, the TCS-ADUL group showed decreased airway volume and minimal cross-sectional areas compared to the CON group. There were also significant differences between TCS-ADOL and TCS-ADUL, with significantly lower airway volumes in the TCS-ADOL group. Strong positive correlations were found between certain airway measurements in the TCS-ADOL group, which were not observed in adults. The upper airways of adults with TCS are dimensionally similar to those of nonsyndromic individuals, despite absolute value reductions found in the syndromic group. The reduced airway in the adolescent population suggests significant potential for growth, mainly in pharyngeal dimensions.

HYOID BONE POSITION AND PHARYNGEAL SPACE IN DIFFERENT VERTICAL JAW DYSPLASIAS

Background: The position of hyoid bone and pharyngeal space is affected by various factors. One of the factors is vertical malocclusion. This study aimed to evaluate the position of hyoid bone and pharyngeal space in different vertical jaw dysplasias. Methods: In total 102 lateral cephalograms of 70 females and 32 males in the age range of 15 to 25 years were selected from records of the patients who visited to the Department of Orthodontics and Dentofacial Orthopedics, UCMS College of Dental Surgery Bhairahawa, Nepal. For the vertical plane of the face, sample was divided into three groups based on Frankfort mandibular plane angle: Group 1 (n=34; normal growth pattern) group 2 (n=34; horizontal growth pattern) and group 3 (n =34; Vertical Growth Pattern). Results: The anteroposterior position of the hyoid bone was found significantly forward in horizontal grower compared with normal and vertical grower (p&lt;0.05). There was no statistically significant difference in vertical positioning of the hyoid bone among the patients with different growth patterns. There was no statistically significant difference in the axial orientation of the hyoid bone in patients with different growth patterns. Upper pharyngeal space was significantly different in different facial skeletal patterns (p=0.019) whereas, lower pharyngeal space had no significant association. Conclusions: The position of the hyoid bone in horizontal growth pattern group was more anterior than the vertical growth pattern group. The upper pharyngeal space was found narrower in vertical growth pattern than horizontal and normal growth patterns.

Thickness of the nasolacrimal duct and the adjacent maxillary bone in different skeletal patterns using MSCT: A retrospective study

Objectives: To evaluate the anatomy of the nasolacrimal duct and the adjacent maxillary bone thickness using multislice computed tomography. Methods: Tomographic images of 92 individuals (184 sides) were analyzed according to sex, side, and sagittal (Class I, II, and III) and vertical (mesocephalic, brachycephalic, and dolichocephalic) skeletal patterns. The largest diameters of the nasolacrimal duct and the thickness of the adjacent maxillary bone were measured when the lacrimomaxillary suture was completely visible. In addition, the measurements were performed 2 mm above and below the midpoint. The maxillary bone and nasolacrimal duct measurements were analyzed by one-way ANOVA with Tukey’s post-hoc test. Results: Females had a significantly narrower lacrimal duct at the midpoint (p=0.026) and 2 mm above it (p=0.025). Maxillary bone thickness was greater in Class II individuals compared to Class I at the midpoint (p=0.012) and 2 mm above it (p=0.027). The dolichocephalic group had greater maxillary bone thickness at the midpoint (p=0.014) and 2 mm below it (p=0.005) compared to the brachycephalic group. Maxillary bone thickness was greater in mesocephalic individuals compared to dolichocephalic individuals (p=0.04). Conclusions: Brachycephalic Class I individuals have lower maxillary bone thickness adjacent to the nasolacrimal duct, which increases the risk of injury during the bone fixation process.

Influence of orthodontic bracket prescription on smile attractiveness in patients with different sagittal skeletal patterns: A 3-dimensional cross-sectional study

The objective of this study was to evaluate the influence of orthodontic bracket prescription on smile attractiveness. Three women were chosen according to their sagittal skeletal pattern: skeletal Class I, II, or III malocclusion. For each, 3 smiling pictures were taken in frontal, oblique, and lateral views. The maxillary arch was then scanned, and a 3-dimensional digital model was constructed on the OrthoAnalyzer software. The information of 3 orthodontic prescriptions, namely Roth, MBT, and Ricketts, was simulated after the virtual placement of orthodontic brackets on 10 maxillary teeth. The simulations were then superimposed on the smile photographs in the 3 views, creating a total of 27 images. Groups of orthodontists, dentists, and laypeople rated the attractiveness of each smile using the visual analog scale. This study included 167 evaluators: 54 orthodontists, 54 dentists, and 59 laypersons. In terms of orthodontic prescription, MBT esthetic scores were 4% lower than Roth scores (P<0.001), and Ricketts scores were 13.6% lower than Roth scores (P<0.001). In terms of skeletal pattern, Class II and III scores were 15.0% and 16.4% lower than Class I scores, respectively (P<0.001). Regarding the smiling view, oblique view scores were 3.1% lower than frontal view scores (P= 0.031), whereas lateral view scores were 8.4% lower than frontal view scores (P<0.001). In contrast to gender and age, the specialty of the evaluators significantly affected the esthetic rating of the smiles. The attractiveness of a smile is affected by the prescription of the brackets. The Roth prescription tends to obtain the most favorable esthetic scores, especially in sagittal smiling images. Profile smiles with excessively proclined incisors are considered unattractive. Different views of the same smile do not get similar esthetic scores because sagittal views are rated the most severely.

Three-dimensional assessment of periodontal support of lower incisors for skeletal Class II malocclusion undergoing presurgical orthodontic treatment with different vertical skeletal patterns

BackgroundThe aim of the present study was to compare periodontal support changes during retraction of mandibular anterior teeth for skeletal Class II malocclusion with different facial divergence and to analyze relevant factors influencing bone remodeling by applying three-dimensional (3D) cone-beam computed tomography (CBCT) reconstruction technology.MethodsForty-eight patients with Class II malocclusion requiring surgical orthodontic treatment enrolled in the study were divided into the hyperdivergent group (n = 16), normodivergent group (n = 16) and hypodivergent group (n = 16) according to their vertical skeletal patterns. Cone-beam computed tomography (CBCT) scans were obtained before treatment (T1) and after presurgical orthodontic treatment (T2). The two-dimensional (2D) alveolar bone morphology, movement of mandibular central incisors and volume of the alveolar bone around incisors were measured on the labial and lingual sides by 3D CBCT reconstruction technology. Statistical analyses were performed with one-way ANOVA, paired t tests and multiple linear regression.ResultsDuring presurgical orthodontic treatment, the alveolar bone height on the labial side of the hyperdivergent group decreased significantly (P ≤ 0.05), but was maintained in the normodivergent and hypodivergent groups (P > 0.05). However, the alveolar bone volume, alveolar bone thickness at each level and alveolar bone height on the lingual side decreased significantly for all the groups. Apart from the initial morphometric measurements at T1, the morphology of lingual alveolar bone at T2 was significantly influenced by the direction and amount of tooth movement. Horizontal retraction and vertical protrusion of the root apex were negatively related to the alveolar bone on the lingual side after presurgical orthodontic treatment.ConclusionFor Class II malocclusion patients undergoing presurgical orthodontic treatment, the changes in the periodontal support of the lower central incisors varied in different vertical skeletal patterns. There exists a great periodontal risk of alveolar bone resorption on the lingual side for various vertical types. To avoid alveolar bone deterioration, it is essential to investigate the bone remodeling of patients with different alveolar bone conditions and cautiously plan tooth movement prior to orthodontic treatment. Moreover, 3D measurements based on CBCT construction can provide complementary information to traditional 2D measurements.

Evaluation of maxillary sinus dimensions and volume in different sagittal and vertical facial types: A CBCT based study

The study was carried out to evaluate the dimensions and volume of maxillary sinus along with its distribution among different sagittal and vertical skeletal facial types.A sample of 90 patients was segregated into three sagittal groups based on ANB angle which was further subdivided into three vertical subgroups based on SN-GoGn angle using NNT software. The volumetric assessment was carried out usingHoros software while the linear measurements were performed on CBCT images analysed in NNT software. The inter-group statistical comparison of means of continuous variables was done using Analysis of Variance (ANOVA) with Bonferroni’s multiple group comparisons.The maxillary sinus volume did not differ significantly across different sagittal and vertical skeletal patterns, the mean sinus volume being 13.08 (+/- 5.38) cu mm among the study population. The maxillary sinus length in Class I skeletal pattern was 3.65 cm (Hyperdivergent group), 3.64 cm (normodivergent group) and 3.52 cm (Hypodivergent group).The distribution of maxillary sinus dimensions did not differ significantly across the different skeletal and vertical facial types. The only statistically significant finding was the greater maxillary sinus length in all three types of vertical skeletal patterns of Class I as compared to Class III malocclusion.

Three-dimensional quantification of mandibular asymmetries in Caucasian adult patients with different sagittal and vertical skeletal patterns. A cone beam study using 3D segmentation and mirroring procedures

IntroductionAn accurate identification of mandibular asymmetries is required by modern orthodontics and orthognathic surgery to improve diagnosis and treatment planning of such deformities. Although craniofacial deformities are very frequent pathologies, some types of asymmetries can be very difficult to assess without the proper diagnostic tools. The purpose of this study was to implement the usage of three-dimensional (3D) segmentation procedures to identify asymmetries at the mandibular level in adult patients with different vertical and sagittal patterns where the asymmetries could go unnoticed at the observational level.MethodsThe study sample comprised 60 adult patients (33 women and 27 men, aged between 18 and 60 years). Subjects were divided into 3 sagittal and vertical skeletal groups. CBCT images were segmented, mirrored and voxel-based registered with reference landmarks using ITK-SNAP® and 3DSlicer® software’s. 3D surface models were constructed to evaluate the degree of asymmetry at different anatomical levels.ResultsThere was a degree of asymmetry, with the left hemimandible tending to contain the right one (0.123 ± 0.270 mm (CI95% 0.036–0.222; p < 0.001). Although the subjects under study did not present significant differences between mandibular asymmetries and their sagittal or vertical skeletal pattern (p = 0.809 and p = 0.453, respectively), a statistically significant difference has been found depending on the anatomical region (p < 0.001; CI95%=1.020–1.021), being higher in the condyle, followed by the ramus and the corpus.ConclusionsAlthough mandibular asymmetries cannot be correlated with vertical and sagittal skeletal patterns in symmetric patients, knowledge about 3D segmentation procedures and color maps can provide valuable information to identify mandibular asymmetries.

Three-dimensional analysis of posterior tooth inclinations in transverse and sagittal relationships: A cross-sectional study

To compare tooth inclinations in different sagittal skeletal patterns and transverse maxillary relationships three-dimensionally. A cross-sectional study carried out with 132 three-dimensional digital models in the complete permanent dentition divided into six groups (n=22); three groups with maxillary atresia: G1- skeletal class I, G2- skeletal class II and G3-skeletal class III; three groups without maxillary atresia: G4- skeletal class I; G5- skeletal class II and G6- skeletal class III. The comparison between the skeletal pattern was performed by the non-parametric tests of Kruskal Wallis and Dunn and between the groups by the non-parametric test of Mann Whitney. Subjects with skeletal class II and maxillary atresia had a greater lingual inclination of the maxillary teeth than those with class I and III; Subjects with skeletal class II without atresia had a less lingual inclination of the mandibular molars than the other classes (p<0.05). The maxillary premolars showed no variation in dental inclination with atresia, independent of the skeletal class in G1, G2, and G3 (p>0.05). The mandibular premolars showed that the groups without atresia G4, G5, and G6 presented no significant difference (p>0.05). Lower premolars in skeletal class III malocclusion individuals with atresia had a more negative inclination than the others. There is a difference in the inclination of posterior teeth between individuals with and without maxillary atresia and skeletal classes I, II, and III.

Molecular compartmentalization in a syncytium: restricted mobility of proteins within the sea urchin skeletogenic mesenchyme.

Multinucleated cells, or syncytia, are found in diverse taxa. Their biological function is often associated with the compartmentalization of biochemical or cellular activities within the syncytium. How such compartments are generated and maintained is poorly understood. The sea urchin embryonic skeleton is secreted by a syncytium, and local patterns of skeletal growth are associated with distinct sub-domains of gene expression within the syncytium. For such molecular compartments to be maintained and to control local patterns of skeletal growth: (1) the mobility of TFs must be restricted to produce stable differences in the transcriptional states of nuclei within the syncytium; and (2) the mobility of biomineralization proteins must also be restricted to produce regional differences in skeletal growth. To test these predictions, we expressed fluorescently tagged forms of transcription factors and biomineralization proteins in sub-domains of the skeletogenic syncytium. We found that both classes of proteins have restricted mobility within the syncytium and identified motifs that limit their mobility. Our findings have general implications for understanding the functional and molecular compartmentalization of syncytia.

The people behind the papers - Jian Ming Khor and Charles Ettensohn.

Syncytia are multinucleated cells that form distinct functional compartments. In a new paper in Development, Charles Ettensohn and colleagues use the sea urchin embryonic skeleton to study how specialized compartments are generated in a syncytium to give rise to local skeletal patterns. We caught up with first author Jian Ming Khor and corresponding author Charles Ettensohn, Professor at Carnegie Mellon University, to find out more about their research.

Postcontraction [acetylcarnitine] reflects interindividual variation in skeletal muscle ATP production patterns in vivo.

In addition to its role in substrate selection (carbohydrate vs. fat) for oxidative metabolism in muscle, acetylcarnitine production may be an important modulator of the energetic pathway by which ATP is produced. A combination of noninvasive magnetic resonance spectroscopy measures of cytosolic acetylcarnitine and ATP production pathways was used to investigate the link between [acetylcarnitine] and energy production in vivo. Intracellular metabolites were measured in the vastus lateralis muscle of eight males (mean: 28.4 yr, range: 25-35) during 8 min of incremental, dynamic contractions (0.5 Hz, 2-min stages at 6%, 9%, 12%, and 15% maximal torque) that increased [acetylcarnitine] approximately fivefold from resting levels. ATP production via oxidative phosphorylation, glycolysis, and the creatine kinase reaction was calculated based on phosphorus metabolites and pH. Spearman rank correlations indicated that postcontraction [acetylcarnitine] was positively associated with both absolute (mM) and relative (% total ATP) glycolytic ATP production (rs = 0.95, P = 0.001; rs = 0.93, P = 0.002), and negatively associated with relative (rs = -0.81, P = 0.02) but not absolute (rs = -0.14, P = 0.75) oxidative ATP production. Thus, acetylcarnitine accumulated more when there was a greater reliance on "nonoxidative" glycolysis and a relatively lower contribution from oxidative phosphorylation, reflecting the fate of pyruvate in working skeletal muscle. Furthermore, these data indicate striking interindividual variation in responses to the energy demand of submaximal contractions. Overall, the results of this preliminary study provide novel evidence of the coupling in vivo between ATP production pathways and the carnitine system.NEW & NOTEWORTHY Production of acetylcarnitine from acetyl-CoA and free carnitine may be important for energy pathway regulation in contracting skeletal muscle. Noninvasive magnetic resonance spectroscopy was used to investigate the link between acetylcarnitine and energy production in the vastus lateralis muscle during dynamic contractions (n = 8 individuals). A positive correlation between acetylcarnitine accumulation and "nonoxidative" glycolysis and an inverse relationship with oxidative phosphorylation, provides novel evidence of the coupling between ATP production and the carnitine system in vivo.

Pediatric Le Fort, Zygomatic, and Naso-Orbito-Ethmoid Fractures.

Fractures of the pediatric midface are infrequent, particularly in children in the primary dentition, due to the prominence of the upper face relative to the midface and mandible. With downward and forward growth of the face, there is an increasing frequency of midface injuries seen in children in the mixed and adult dentitions. Midface fracture patterns seen in young children are quite variable; those in children at or near skeletal maturity mimic patterns seen in adults. Non-displaced injuries can typically be managed with observation. Displaced fractures require treatment with appropriate reduction and fixation and longitudinal follow-up to evaluate growth.

Nasal Morphology as an Indicator of Maxillomandibular Skeletal Pattern.

To determine the correlation of nasal morphology with maxillary and mandibular patterns. Descriptive cross-sectional study. Place and Duration of the Study: Department of Orthodontics, Liaquat College of Medicine and Dentistry and Qamar Dental Hospital, Karachi, Pakistan, , Liaquat College of Medicine & Dentistry and Darul Sehat Hospital Karachi, Pakistan from January to June, 2022. The pre-treatment lateral cephalograms of 120 patients, aged 18-35 years were included in the study. Eleven nasal parameters were traced on lateral cephalograms and correlated with four maxillary and mandibular skeletal parameters by Pearson correlation coefficient test using SPSS version 26.0. Nasal bone length and nasal base angle showed a negative correlation with maxillary and mandibular position. Nasal upward tip angle was correlated positively with maxillary position whereas nasal tip angle was found to be negatively correlated with maxillary length. A negative correlation was observed between nasolabial angle and mandibular position. Nasal bone angle depicted a positive correlation with maxillary position and a negative correlation with jaw lengths and mandibular inclination. Nasal morphology has a strong correlation with maxillary as well as mandibular base lengths and position but not with inclination of the jaws. The acquaintance of the relationship of different nasal parameters with jaw parameters might be helpful in diagnosis and treatment planning and to attain the favourable treatment outcomes in patients undergoing orthodontic treatment, orthopedic interventions, orthognathic, genioplasty, rhinoplasty, profiloplasty and other procedures. Nasal morphology, Maxillomandibular skeletal pattern, Jaw length, Jaw position, Jaw inclination.

The Correlation between Mandibular Arch Shape and Vertical Skeletal Pattern.

Background and Objectives: The aim of this study was to evaluate the correlation between the mandibular arch shape and the vertical skeletal pattern in growing patients. Materials and Methods: A total of 73 Caucasian patients (33 males and 40 females; mean age 9.4) were retrospectively enrolled from a pool of patients treated in chronological order at the Department of Orthodontics, University of Foggia, Italy, from April 2018 to December 2021. Each patient received a laterolateral radiograph and a digital scan of the dental arch. Eight cephalometric parameters (lower gonial angle, intermaxillary angle, divergence angle, Wits index, Jarabak ratio, OP-MP angle, PP-OP angle, and ANB) and five dental measurements (posterior mandibular arch width, anterior mandibular arch width, mandibular occlusal angle, posterior width on distobuccal molar cusps, and molar angle) were analyzed and then compared. A Spearman's rho correlation test between the cephalometric measurements and the dental measurements was performed. Statistical significance was set at p < 0.05. Results: A negative statistically significant correlation was found between the Jarabak ratio and the intermolar angle; a statistically significant correlation was also observed between the Wits index, the posterior mandibular width, and the occlusal mandibular angle; the ANB angle and the occlusal mandibular angle; the intermaxillary angle (PP-PM) and the mandibular occlusal angle, posterior mandibular width on the disto-vestibular cusp, and the intermolar angle; and the OP-MP angle and mandibular occlusal angle and the posterior mandibular width on the disto-vestibular cusp. Conclusions: The mandibular arch form may be related to certain predisposing features in craniofacial morphology, such as jaw divergence, the Jarabak ratio, and the intermaxillary angle.