Skeletal Malocclusion Research Articles

Position of the mandibular foramen in relation to the occlusal plane in children with skeletal class malocclusion

Frequently, practitioners use the inferior alveolar nerve block in the procedures desired on the teeth in the mandible and the surrounding tissues. This study aimed to reveal the position of the mandibular foramen (MF) according to the malocclusion types on panoramic radiographs of children aged 9-18 years living with malocclusion in Turkey. Panoramic and cephalometric radiographs of 330 patients between 9 and 18 years old were analyzed retrospectively. We grouped the skeletal malocclusion types as Class 1, 2, and Class 3 based on lateral cephalometric radiographs and evaluated the location of MF in malocclusion types according to age and gender. We observed that the distances to the occlusal plane, posterior edge, and gonion point increased with age while the distance to the anterior edge decreased. There was a significant difference according to age and gender in all malocclusion types (p<0.05). We determined that the MF was positioned upward parallel to the increase in age and approached the midpoint of the ramus of the mandible from the posterior. The fact that MF is placed higher than the occlusal plane in Class 3 malocclusions compared to other types and differs by gender will guide clinicians in providing effective and safe inferior alveolar nerve block in pediatric malocclusions.

Calcification patterns and morphology of Sella turcica are related to anteroposterior skeletal malocclusions: A cross-sectional study

BackgroundThe sphenoid bone is an irregular, unpaired, symmetrical bone located in the middle of the anterior skull and is involved in craniofacial growth and development. Since the morphology of Sella turcica (ST) is associated with different craniofacial patterns, this study aimed to investigate if there is a correlation between ST morphology on the one hand and sagittal craniofacial patterns on the other hand. MethodsThis study was conducted with a convenience sample that included Brazilian individuals undergoing orthodontic treatment. Lateral cephalograms were used to evaluate the calcification pattern and morphology of ST, as well as skeletal class by analyzing the ANB angle. Pearson's chi-square test with Bonferroni post-hoc test was performed to evaluate the association between ST calcification pattern and morphology, and anteroposterior skeletal malocclusion. The established significance level was 0.05. ResultsThe study collective was comprised of 305 orthodontic patients (178 (58.4 %) female, 127 (41.6 %) male), who had a mean age of 23.2 (±10.6) years. 131 participants (42.9 %) presented skeletal class I, 142 (46.6%) skeletal Class II, and 32 (10.5%) had a skeletal class III. The degree of prognathism of the mandible showed a homogenous distribution within the study collective (91 (29.9 %) orthognathic, 100 (32.9 %) retrognathic, 113 (37.2 %) prognathic mandible). Concerning the maxilla, 92 (30.2%) individuals presented an orthognathic upper jaw, whereas 60 (19.7%) showed maxillary retrognathism and 153 (50.2%) maxillary prognathism. Compared to patients with skeletal class I, skeletal class III individuals presented significantly more hypertrophic posterior clinoid process (p<0.007) and pyramidal shape of the dorsum of the ST (p<0.038). ConclusionsOur results suggest that the hypertrophic posterior clinoid process and pyramidal shape of the ST dorsum are more prevalent in individuals with skeletal class III malocclusion.

Effect of Orthognathic Surgery on Pre-existing Temporomandibular Disorders.

The management of patients with pre-existing temporomandibular disorders (TMDs) undergoing orthognathic surgery remains a subject of ongoing debate. This study aimed to profile these individuals and evaluate the correlation between orthognathic surgery and alterations in TMD indicators and symptoms. We conducted a retrospective cohort investigation involving patients with skeletal malocclusion and established TMDs. Variables of interest encompassed the performance of orthognathic surgery, documented TMDs (including temporomandibular joint (TMJ) sounds, TMJ pain, muscle discomfort, and jaw locking), and patients' self-assessments of TMJ and muscle pain using a visual analog scale (VAS). The primary outcome measures focused on changes in TMD indicators and symptoms. Among the study cohort, 73.4% exhibited skeletal class III malocclusion, while 26.6% presented with skeletal class II malocclusion. Notably, patients classified as skeletal class III were significantly younger than their skeletal class II counterparts (mean age: 23.06±5.37 vs. 26.71±7.33; P=0.034). The most prevalent pre-existing TMD complaint was TMJ sounds (65.5%), followed by TMJ pain (39.1%), muscle discomfort (23.4%), and jaw locking (12.5%). Skeletal class II patients were more likely to experience TMJ sounds compared to skeletal class III patients (88.2% vs. 57.4%; P=0.022). Statistically significant improvements were observed in the VAS assessments among class III patients following surgery. A majority of patients with pre-existing TMDs seeking orthognathic surgery exhibited skeletal class III malocclusion and were younger than those with skeletal class II malocclusion. Importantly, orthognathic surgery was associated with positive changes in TMD indicators and symptoms in these patients.

Does the 2D:4D Ratio Exhibit Sexual Dimorphism in Skeletal Malocclusions? A Retrospective Study

Objective: It is noteworthy that the 2D:4D ratio, also called as the ratio of the length of the second digit (2D) to the length of the fourth digit (4D), which has the ability to remain stable lifetime, is associated with various hormones and craniofacial skeletal development as a biomarker in early diagnosis. The aim of this study was to investigate the relationship between the 2D:4D ratio and sagittal skeletal malocclusions. Materials and Method: A total of 117 patients (57 females, mean age 13.44±1.98; 60 males, mean age 13.56±2.14) with normal vertical angles were included, and the groups were divided into skeletal classes I, II and III according to the ANB angle. The skeletal class I group consisted of patients with ideal values for both SNA and SNB angles. The skeletal groups were further divided into female and male subgroups by gender. SNA, SNB, SN/GoGn and ANB angles and ANS-PNS and Go-Pog lengths were measured on pretreatment lateral cephalometric radiographs. Digit length measurements were performed with a digital caliper capable of measuring up to 0.01 mm. The 2D:4D ratio was calculated for each group by dividing the 2D length by the 4D length. Statistical analyzes were performed with independent sample t-test and one-way ANOVA in normally distributed data, and Kruskal-Wallis and Man-Whitney U tests in non-normally distributed data. Statistical significance level was accepted as p &lt; 0.05. Results: There was no statistically significant difference between right and left 2D:4D ratios and right and left digit lengths of the same hand in skeletal classes. While statistically significant sexual dimorphism was observed in digit lengths and 2D:4D ratios in skeletal class Is, it was observed that the significance decreased as the severity of malocclusion increased. No significant difference was found in terms of sexual dimorphism in skeletal class IIIs. There was no significantly difference between the skeletal groups in terms of 2D:4D ratio and length measurements. Conclusions: Sexual dimorphism was seen in all parameters, especially in skeletal class I patients, and it was found that males had more 2D and 4D lengths and a lower 2D:4D ratio than females. It was also concluded that as the severity of malocclusion increased, the statistical significance of the parameters observed with sexual dimorphism decreased. The fact that sexual dimorphism is fully seen in skeletal class Is but not in skeletal class III has led to the use of the 2D:4D ratio as a diagnostic biomarker in the early diagnosis of sagittal skeletal malocclusions by gender.

Relationship between Skeletal Malocclusion and Radiomorphometric Indices of the Mandible in Long Face Patients.

This study aimed to assess the relationship between skeletal malocclusion and radiomorphometric indices of the mandible in long face patients. This cross-sectional study evaluated 174 lateral cephalograms and panoramic radiographs of long face patients between the ages of 17 and 30 presenting at the Orthodontics Department of Qazvin Dental School. The gonial angle, antegonial angle, type of antegonial notch, and depth of antegonial notch were measured bilaterally on panoramic radiographs. The correlation between the radiomorphometric parameters and the type of occlusion was analyzed using one-way ANOVA, independent t-test, Chi-square test, and Fisher's exact test (alpha = 0.05). The mean size of gonial angle was significantly different among the three classes of occlusion (p = 0.046), while the difference was not significant regarding the antegonial angle size and antegonial notch depth (p > 0.05). An independent t-test showed that the mean sizes of gonial angle (p = 0.026) and antegonial angle (p = 0.036), and the antegonial notch depth (p = 0.046) in males, were significantly greater than the values in females. According to the Chi-square and Fisher's exact test, the right antegonial notch type was significantly different among the three classes of malocclusion (p = 0.006), while this difference was not significant in the left side (p = 0.318). The right antegonial notch type II was more common in males, while the right antegonial notch type I was more common in females (p = 0.014). According to the results, the indices of gonial angle and type of antegonial notch can be clinically useful for predicting the growth rate of the mandible and designing the appropriate treatment in long face patients.

Role of the Growth Hormone Receptor (GHR) Gene in Skeletal Class II Malocclusion and Its Significant Influence on the Skeletal Facial Profile in Both the Sagittal and Vertical Dimensions: A Systematic Review.

This systematic review aims to determine the role of the growth hormone receptor (GHR) gene in skeletal malocclusion and its significant influence on the growth of the maxilla and the mandible in both sagittal and vertical dimensions. A search of the electronic databases of PubMed, Google Scholar, and Cochrane up to and including the year 2023 was made. In addition to this, a hand search of orthodontic and dentofacial orthopaedic journals was carried out. This search included randomized control trials. The Mesh terms used were "skeletal class II malocclusion", "mandibular retrognathism", "sagittal malocclusion", "genetic expression", "genetic factors", "genetic study", "genetic polymorphism", and "single nucleotide polymorphism". The inclusion criteria included studies such as clinical trials and orthopaedic appliances in the presurgical phase. The exclusion criteria for the study were studies not in the English language, case reports, case series, and studies with irrelevant data. It has been cited in various literature that polymorphic variations of the GHR gene could cause variations in mandibular morphogenesis affecting both the mandibular body length and ramal height. However, its effects are quite variable and are based on different population groups. Polymorphism of the GHR gene can be considered a reliable indicator predicting variations in affecting the growth of the mandible with greater significance in affecting the vertical ramal height compared to the body length of the mandible. Its effects on the maxillary skeletal base are rather limited comparatively.

Cephalometric Association Between Various Shapes of Soft Palate with Different Growth Pattern and Age Groups in Skeletal Class I, II and III Malocclusion

OBJECTIVE:The aim of this study was to find cephalometric association between various shapes of soft palate with different growth pattern and age groups in skeletal class I, II and III malocclusion METHODOLOGY:The pretreatment lateral cephalograms of 382 patients was collected from the department of Orthodontics, Liaquat College of Medicine &amp; Dentistry, Karachi. The study included 96 males and 286 females between the ages of 11 to 30 years. All the patients were divided according to skeletal classification of malocclusion. The type of skeletal malocclusion, growth pattern and the morphological variations of soft palate were assessed. The differences in the proportion of soft palate morphology among skeletal malocclusion and growth pattern were calculated. Variation of the soft palate morphology among the genders and different age groups were also determined. RESULTS: Subjects with Type 1 "leaf-shaped" soft palates were more prevalent (43.2%) whereas, The Type 4 "Straight-line" soft palate was least common (2.9%). Type 1 "leaf-shaped" soft palate was the most common in all skeletal malocclusion classes, growth pattern types and both genders CONCLUSIONS: This study found significant association between soft palate morphology with type of skeletal malocclusion and gender. No significant association found between soft palate morphology and types of growth pattern KEYWORDS: soft palate shapes, growth pattern, age groups, skeletal malocclusion, lateral cephalogram.

The concept of AI-assisted self-monitoring for skeletal malocclusion.

Background: Skeletal malocclusion is common among populations. Its severity often increases during adolescence, yet it is frequently overlooked. The introduction of deep learning in stomatology has opened a new avenue for self-health management. Methods: In this study, networks were trained using lateral photographs of 2109 newly diagnosed patients. The performance of the models was thoroughly evaluated using various metrics, such as sensitivity, specificity, accuracy, confusion matrix analysis, the receiver operating characteristic curve, and the area under the curve value. Heat maps were generated to further interpret the models' decisions. A comparative analysis was performed to assess the proposed models against the expert judgment of orthodontic specialists. Results: The modified models reached an impressive average accuracy of 84.50% (78.73%-88.87%), with both sex and developmental stage information contributing to the AI system's enhanced performance. The heat maps effectively highlighted the distinct characteristics of skeletal class II and III malocclusion in specific regions. In contrast, the specialist achieved a mean accuracy of 71.89% (65.25%-77.64%). Conclusions: Deep learning appears to be a promising tool for assisting in the screening of skeletal malocclusion. It provides valuable insights for expanding the use of AI in self-monitoring and early detection within a family environment.

New insights into the genetics of mandibular retrognathism: novel candidate genes.

Mandibular retrognathism (MR) is acommon skeletal malocclusion in humans with astrong genetic component. Single nucleotide polymorphisms (SNPs) in genes encoding epidermal growth factor (EGF) and EGF receptor (EGFR) could be involved in the etiology of mandibular retrognathism. Therefore, in this study, we investigated whether SNPs in the genes encoding for EGF and EGFR are associated with MR in German teenagers. This nested case-control study evaluated German orthodontic patients, aged 10-18years. DNA, which was isolated from buccal epithelial cells using two cytobrushes, was used for genotyping analysis and digital pretreatment lateral cephalograms were examined to calculate SNB and ANB. Patients with aretrognathic mandible (SNB < 78°) were included as cases, while patients with an orthognathic mandible (SNB = 78-82°) were included as controls. Four SNPs in the genes encoding for EGF and EGFR were chosen and genotyped using real-time PCR. Allele, genotype, and haplotype frequency were compared across groups (α = 5%). Finally, 119 patients were included in this study (45orthognathic mandible, 74retrognathic mandible). The minor alleleG in rs4444903 (EGF) was statistically more frequent in individuals with an orthognathic mandible (p = 0.008). The haplotype formed by the mutant alleles for rs4444903|rs2237051 (EGF; G|A) was statistically more frequent in the orthognathic mandible group (p = 0.007). The SNPs rs4444903 and rs2237051 in EGF, and rs2227983 in EGFR were statistically associated with adecreasing risk of developing aretrognathic mandible according to univariate and multivariate statistical analysis (p < 0.05). SNPs in EGF (rs4444903 and rs2237051) and EGFR (rs2227983) were associated with MR in our German sample and could be genetic biomarkers for early and individualized diagnostic identification of retrognathic mandibular development by means of genetic screening tests.

Vertical Dentofacial Skeletal Divergency Is Not Linked with Oral Health-Related Quality of Life

The aim of this study is to assess how vertical skeletal malocclusion affects oral health-related quality of life (OHRQoL) among a sample of individuals comprising adolescents, young adults, and adults seeking orthodontic treatment. From January 2019 to March 2020, participants were consecutively enrolled. The assessment of OHRQoL involved measurement using the oral health impact profile (OHIP-14). Lateral cephalograms were performed to measure the vertical skeletal divergency with four cephalometric measurements. Descriptive and inferential statistical analyses were performed. The Mann–Whitney test was applied to compare OHRQoL scores according to the vertical dimension category. The mean age of the participants ranged between 30.3 ± 14.9 and 29.9 ± 14.4 and there was a majority of female participants, between 64.1% and 65.9%. There were no statistically significant differences observed between hyperdivergent and normodivergent groups in either the total score or any domain of the OHIP-14 questionnaire. Individuals with hyperdivergent facial morphology did not show a reduced OHRQoL compared with a normodivergent facial type.

A finite element study comparing Advansync® and Twin Block in mandibular anterior repositioning.

This study aims to utilize the finite element method (FEM) to compare the dentoalveolar and mandibular effects associated with anterior mandibular repositioning using AdvanSync® (ADV) and Twin Block (TB). A patient with Class II skeletal malocclusion and mandibular retrognathism was selected. A TB appliance was subsequently applied. Computed Tomography (CT) scans were acquired at the beginning of treatment (T1) and 8 months later (T2). Concurrently, a numerical TB model was validated through FEM simulations, which were compared with the T2 results. The ADV appliance was virtually simulated to evaluate stress and deformation on the condyle, symphysis, first lower molar and lower central incisors. Both simulations demonstrated significant mandibular advancement. However, ADV led to less incisor proclination and more molar intrusion compared to TB. ADV exhibited increased stress in the lower molar area, while TB had higher stress in the lower incisor region. Stress and deformations in the condyle and mandibular symphysis were similar in both simulations, with the highest stress observed at the condylar neck and the lowest at the upper pole of the condylar head. Both appliances achieved similar levels of mandibular advancement, with greater proclination of the lower central incisors and more widespread distribution of stress and molar intrusion when using ADV compared to TB.

Agreement Between Two Cephalometric Analyses of Facial Growth Direction and Biotype

Cephalometry is a morphological and descriptive diagnostic method that provides relevant data on skeletal and dentoalveolar malocclusions of patients seeking orthodontics treatment. Several authors have proposed different cephalometric measurements to determine facial growth direction and facial biotype, the results of these different measurements from the same patient do not always agree on the diagnosis. The aim of this study was to determine the level of agreement between Ricketts and Björk-Jarabak cephalometric analyses for the determination of facial growth direction and facial biotype in patients from a population of Yucatan, Mexico. A total of 260 lateral cephalograms of patients between 18 and 59 years of age were digitally traced using the Ricketts and Björk-Jarabak cephalometric analyses to determine the direction of facial growth and facial biotype using Dolphin Imagine software. Cohen's kappa statistical test was performed to establish the strength of agreement between the diagnostic results obtained by the cephalometric analyses. A poor diagnostic concordance strength was found for growth direction (K=0.105), and acceptable for facial biotype (K=0.362). The concordance strengths for each diagnostic possibility (level) ranged from slight to acceptable, except for the brachyfacial and dolichofacial biotypes, with a moderate strength of agreement. In conclusion, the Ricketts and Björk-Jarabak cephalometric measurements used for the determination of facial biotype and facial growth direction could suggest non-concordant diagnostic assessments in some individuals.

A Cephalometric Study of Sella Turcica: Correlation of Its Size with Different Skeletal Malocclusions.

The present study was done to determine the size of the sella turcica in different skeletal type subjects and to evaluate if any significant difference exists between them, which could be the basis for early diagnosis. A total of 60 lateral cephalograms of patients above 15 years of age were selected and distributed according to skeletal malocclusion into class I (n = 20), class II (n = 20), and 20 class III (n = 20). Syndromic patients (physically/mentally/both) or patients with major illnesses were not included. Two linear measurements of the sella turcica, that is, length and depth in mid-sagittal plane, were obtained in accordance with Silverman and Kisling method. Unpaired t-test and one-way analysis of variance (ANOVA) were performed. The mean length of sella turcica in class I, class II, and class III subjects was 3.81, 3.37, and 3.9, respectively. Similarly, the mean depth of sella turcica in class I, class II, and class III subjects was 7.6, 6.83, and 9.075, respectively. No significant difference in length of the sella turcica could be found between different skeletal types. Maximum depth of sella turcica was found to be in subjects with class III and minimum with class II skeletal types. The linear dimensions of sella turcica can be used to approximate the pituitary gland size. The pedodontist should be familiar with different morphologies of the sella turcica to differentiate normal from abnormal appearance so that treatment can be diagnosed and treated early. Grover N, Khan DUZ, Bhagchandani J, et al. A Cephalometric Study of Sella Turcica: Correlation of Its Size with Different Skeletal Malocclusions. Int J Clin Pediatr Dent 2023;16(S-3):S229-S232.

Upper Airway Dimensions among Different Skeletal Malocclusions: A Retrospective Observational Study by Cephalometric Analysis.

In this retrospective cross-sectional study, lateral cephalometric radiographs of adult patients referred for orthodontic consultation were collected. Cephalometric tracing was performed with dedicated software. For each measure, descriptive statistics were calculated. Cephalometric measurements between the different skeletal classes were compared. Linear regressions were performed between upper airway diameters and cephalometric measurements, sex and age. Significance was predetermined for p < 0.05. Lateral cephalometric radiographs of 120 patients were reviewed. Nasopharynx length (NL) and depth (PD) measurements were significantly shorter in skeletal class III patients (p < 0.05). The superior pharyngeal airway space (SPAS) was found to be significantly shorter in class III patients as compared to class II patients (p < 0.05), and the mean airway space (MAS) of class I patients was found to be significantly shorter compared to class II patients (p < 0.05). Palate length (PL) values were found to be significantly longer in class I (p < 0.05). Linear regressions showed that the sella-nasion-A point angle (SNA) and Riedel's angle between point A, the nasion and point B (ANB) significantly influenced NL and PD (p < 0.05). Class III patients show significantly shorter nasopharynx measurements; clinicians should consider that this sagittal discrepancy could be related to an altered anatomy of the upper respiratory tract.

The relationship between the dimensions of frontal air sinus and skeletal malocclusions: A systematic review and meta-analysis

ObjectiveThe goal of this systematic review and meta-analysis was to assess whether the dimensions of the frontal air sinus correlate with skeletal malocclusion. Study selectionPubMed, Scopus, Embase, and Google Scholar were searched for relevant studies published up to May 23, 2023. The review included observational studies that compared the dimensions of the frontal air sinus between different skeletal malocclusions. The PECOS method was used in this study (“Population, Exposure, Comparator, Outcome, and Study design”). The search was done using the following English keywords: “frontal sinus” AND “lateral cephalometric” AND “malocclusion” AND “surface area”. ResultsSeven studies were included, which involved 1101 participants, of whom 403 were class I, 375 were class II, and 323 were class III. These studies had a moderate risk of bias. The surface area of the frontal sinus in class III was significantly larger than in class I (standardized difference in means (SDM) = −0.971; 95 % CI = −1.147− −0.796; P < 0.001) and in class II (SDM = −1.535; 95 % CI = −1.732− −1.337; P < 0.001). ConclusionClass III malocclusion is associated with a larger surface area of the frontal sinus compared to classes I and II.

Association between skeletal malocclusion, masseter muscle volume, and bite force: CBCT study

Background/Aim: This study aimed to evaluate the masseter muscle volume and maximum bite force in individuals with different types skeletal malocclusion. The researchers conducted a comparative analysis to assess the relationship between skeletal malocclusion groups and masseter muscle volume, as well as maximum bite force. By examining these variables, the study aimed to provide insights into the underlying mechanisms of craniofacial deformities. Materials and Methods: The study was conducted on a sample of 60 young adult patients (18-30) years. These patients were referred to the clinic for Cone Beam Computed Tomography (CBCT) imaging. Radiological measurements were taken using CBCT images, and bite force was measured using a force measurement sensor. Results: The results of the study indicated a statistically significant relationship in both muscle volume and bite force among the different skeletal malocclusion groups. However, no correlation was observed between muscle volume and other variables. The statistically significant relationship between vertical groups and muscle volume/bite force suggests that these measures could potentially serve as supplementary diagnostic tools. However, the uneven distribution of vertical directional groups indicates that they may not be entirely reliable as diagnostic tools. Therefore, further investigation using larger sample sizes is necessary to better understand the relationship between skeletal malocclusion, bite force, muscle volume. Conclusions: The absence of correlation between muscle volume and bite force suggests that CBCT may not be reliable method for soft tissue imaging. This implies inadequacy of CBCT in capturing soft tissue details.

A retrospective investigation of orthognathic patients and functional needs

Abstract Purpose The present study aimed to explore the malocclusion trends, sagittal skeletal discrepancies, and the index of orthognathic functional treatment need (IOFTN) scores in a sample of Iranian and Turkish orthognathic patients. Methods Four hundred and three orthognathic patients were retrospectively examined (203 Iranian/200 Turkish, 229 females/174 males, aged between 16 and 50 years). The following variables were recorded: malocclusion type (incisor-based), overjet, sagittal skeletal relationship (ANB angle) and IOFTN scores. The sagittal skeletal relationships and malocclusion patterns of the orthognathic patients were statistically examined using Chi-square tests and further explored graphically. The relationship between the IOFTN scores and overjet, as well as the sagittal skeletal discrepancies (ANB angle) was evaluated using box plots and at the 95% confidence interval (CI) in different IOFTN treatment categories (1–3,4,5). The characteristics of a subgroup sample of orthognathic patients and previous studies that identified with low IOFTN scores (1–3) were also explored. Results Class III malocclusions and Class III skeletal patterns were the most prevalent (62.3%), forming 69% and 55.7% of the Turkish and Iranian samples, respectively. Turkish and Iranian samples had more Class III [Mean (SD) ANB angle = -1.24° (4.75°)] and Class II cases [Mean (SD) ANB angle=1.06° (5.63°)], respectively. The mean overjet and reverse overjet for Class II and III malocclusions were 6.96 mm (95% CI, 6.40–7.53 mm) and 3.26 mm (95% CI, 2.87–3.65 mm), respectively. The mean ANB angle for Class II and III malocclusions was 6.64° (95% CI, 6.15°–7.13°) and -3.57° (95% CI, -3.92° to -3.21°), respectively. IOFTN scores of 4 or 5 were identified in 93.8% of the sample. Patients with low IOFTN scores (&lt;4) presented with a nearly normal overjet (mean = 3.19 mm, 95% CI, 2.62-3.76 mm, range = 1–5 mm), accompanied by a wide range of ANB angles [mean (SD)=3.44° (3.86°), range = -4° to 9°] Conclusions The findings at the 95% CI for overjet and the ANB angle can be used as identifiers for patients who would benefit from orthognathic surgery. Analysing patients with a low IOFTN score, particularly with scores of 3.3, 3.10, 2.8, and 1.14, revealed that IOFTN could be used in conjunction with a clinical examination plus diagnostic imaging to facilitate the identification of orthognathic surgery patients.

Prevalence of Ponticulus Posticus among Orthodontic Patients of Iranian Population by Lateral Cephalogram.

The term Ponticulus Posticus (PP) refers to a complete or partial bony bridge on the vertebral artery that passes through the superior-lateral surface of the posterior arch of the atlas. This study was conducted with the aim of investigating the prevalence of ponticulus posticus in orthodontic patients referred to Mashhad Dental School. In this cross-sectional study, one thousand cephalograms were selected from the patients referred to the orthodontics department of Mashhad Dental School between 2017 and 2021. In lateral cephalogram images with appropriate quality, the type of malocclusion was determined using the AudaxCeph software (Audax d.o.o., Ljubljana, Slovenia). Then, the images were evaluated for the presence or absence of PP. For the statistical analysis, chi-square and t-test were used. In this study, 861 lateral digital cephalograms were analyzed. The overall prevalence of PP in the studied population was 17.5%. The prevalence of PP was higher in males than in females (P < 0.001). The variables "presence of PP" (P = 0.056) and "type of PP" (P = 0.522) were found to be independent of age groups. Although class II subjects showed a higher prevalence of PP, skeletal malocclusion classes were not found to be correlated with the presence of PP (P = 0.104) nor with its types (P = 0.958). The current study is considered the primary study that provides data concerning the prevalence of PP in the East of Iran. Our study showed that PP was not rare in this region. More studies with 3D radiological examination are needed to increase the accuracy of diagnosing PP and its prevalence in Iran.

An evaluation of inter-relationship between cervical posture and skeletal malocclusions

Introduction: The growth pattern of the cervical spine and the craniocervical structure are interconnected, inflencing one another both morphologically and functionally. As a result, stretching the head in relation to the cervical spine leads to notable changes, including greater anterior facial height, a shorter sagittal dimension, and a posterior rotation of the jaw. This study was conducted to determine the correlation between cervical curvature in different sagittal skeletal malocclusions and association between cervical lordosis and maxillary and mandibular base. Materials and Method: One hundred fity adults presenting with skeletal Class I, II, and III malocclusion were investigated, irrespective of growth pattern. Three groups were delineated based on the lateral cephalograms of the selected participants: Group 1 (50 skeletal Class I), Group 2 (50 skeletal Class II), and Group 3 (50 skeletal Class III). A comprehensive assessment of cervical posture was conducted through the measurement of manually traced 15 specifi angles, which were carefully chosen to provide a detailed characterization of cervical variations across all three groups. Validity was assessed using Wilk and Kolmogorov-Smirnov tests, and analysis was done using One way Analysis of variance and Post hoc Turkey’s test. Result: Statistically signifiant correlations (P&lt;.05) were found between angles OPT/HOR and CVT/HOR (representing cervical inclination with reference to the true horizontal plane),NSL/CVT, and FH/CVT (indicating middle craniocervical posture), NSL/RL, FH/RL, and NL/RL(reflcting rotation of mandibular ramus). Conclusion: It was proven that changes in head posture and craniofacial development are strongly correlated. The rotation of the mandibular ramus in relation to the cranium was compared between groups, and was found that skeletal Class II malocclusion subjects had more posterior rotation of the ramus in relation to the cranium and extended head compared to those with skeletal Class III and skeletal Class I malocclusion subjects.

Evaluation of safe areas for miniscrew use according to various skeletal anomalies with CBCT.

We aimed to determine safe areas to apply miniscrews in the interradicular region of the maxilla and mandible in individuals with various sagittal skeletal malocclusions. Cone beam-computed tomography images of 159 individuals were used. Individuals were divided into three groups: Class I, Class II, and Class III. In the sagittal plane, 3-6-9-mm apical sections were determined from the alveolar crest apex. The buccal cortical bone thickness, interradicular distance, and buccolingual bone distances were measured. In the buccal cortical bone thickness, we observed statistically significant differences between the classes except for the 1-1 region in the maxilla and all regions and sections in the mandible (p < 0.05). The differences in the buccolingual bone distance between classes were statistically significant, except for the 3-mm and 6-mm sections in the 3-4 and 4-5 regions of the maxilla, the 9-mm sections in the 1-2 and 2-3 regions, the 6-mm and 9-mm sections in the 3-4 region, and the 6-mm section in the 4-5 regions of the mandible (p < 0.05). The differences in the interradicular bone distance were statistically significant between the classes in all regions and sections of the mandible except the 6-mm sections in the 1-2 region and in all sections of the maxilla except the 6-mm sections in the 3-4 region (p < 0.05). We observed significant differences in the buccal cortical bone thickness, interradicular bone distance, and buccolingual bone distance among individuals. Understanding the anatomy of interradicular regions and preventing complications.