Posterior Cranial Base Length Research Articles

Cranial Base Measurements in Skeletal Malocclusion among Orthodontic Patients.

Facial growth and development is necessary for proper orthodontic diagnosis and treatment planning. Growth of cranial base is linked to the overall growth of facial bones, especially the maxilla and mandible. Any change in the amount and direction of growth of the cranial base can have direct or indirect effects on the developing maxilla and mandible. Thus the aim of this study was to determine the linear and angular cranial base measurements in different skeletal malocclusion in Nepalese population. Pretreatment lateral cephalograms of 225 patients aged between 17-30 years were collected. Linear measurements Sella-Nasion (S-N), Sella-Articulare (S-Ar), Articulare-Gonion (Ar-Go), Gonion-Gnathion (Go-Gn) and angular measurements Saddle angle (N-S-Ar), Articular angle (S-Ar-Go) and Gonial angle (Ar-Go-Gn) were measured. In angular measurements statistically significant differences were found in the saddle and gonial angles between class I, II, and III skeletal pattern. In linear measurements, anterior and posterior cranial base lengths were not significantly different among groups however, ramal height and mandibular body length were significantly different among groups with a P value < 0.05. Skeletal class III has a larger gonial angle, ramal height and mandibular length. Males have larger linear measurements and females have larger angular measurements.

Cephalometric Assessment of Condylar Position among Individuals with Different Skeletal Malocclusion Patterns

Introduction: There are variations in growth and orientation of cranial base region where the maxilla and mandible articulate. This leads to differential movement of the maxilla and mandible causing changes in glenoid fossa and condylar position. Therefore, this study was conducted to determine the condylar position in patients with different skeletal sagittal malocclusion patterns. Methods: An analytical cross-sectional study was conducted among 165 individuals, having skeletal Class I, Class II and Class III relationship (55 in each group) selected by convenience sampling method after receiving ethical approval and informed consent. Lateral cephalograms were taken and measurements for determining condylar position were done and compared among three groups. Data were analyzed in SPSS version 16. Kruskal-Wallis H test was used to determine the mean difference in between condylar positions of three skeletal malocclusion patterns and Mann-Whitney U test was done for their pairwise comparison. Results: There was no significant difference in posterior cranial base length (P=0.200) and saddle angle (P=0.517) in three skeletal malocclusion class groups. However, the three malocclusion patterns showed significant differences in gonian angle (P=0.001) and articular angle (P=0.013). Significant moderate negative correlation in saddle angle and articular angle (P&lt;0.001) was observed. Conclusion: The findings of this study concluded that condylar position based on posterior cranial base length was not associated with different skeletal malocclusion patterns. However, articular angle was significantly lower in skeletal class III than in class II.

Enlarged occipital spur and craniofacial morphology: a cephalometric analysis.

This cross-sectional study aimed to investigate the association between the occipital spur length and craniofacial morphology in individuals with occipital spur (OS). The study included cephalometric images from 451 individuals (196 females, 255 males, age range was 9-84years). The spur length and craniofacial characteristics were evaluated using cephalograms. Based on spur length, subjects were divided into two groups: the OS group (N = 209) and the enlarged occipital spur (EOS) group (N = 242). Descriptive statistics, Independent T-test, Mann-Whitney U test, chi-square test, Kruskal-Wallis test, and age- and sex-based stratified analyses were performed. The level of significance was set at p < 0.05. Males had significantly larger spur length than females. Spur length was shorter in individuals under 18 than the groups over 18. After adjusting for gender and age, ramus height, mandibular body length, effective length of maxilla, effective length of mandible, anterior cranial base length, posterior cranial base length, anterior facial height, posterior facial height, facial height index, and lower anterior facial height had statistically significant differences between OS group and EOS group. Males exhibit greater spur length than females. Patients under 18 had a shorter spur length than adults. Linear craniofacial measurements were found to be greater in subjects with EOS than the individuals with OS. The craniofacial growth and development of an individual might be associated with EOS. The causal relationship between EOS and craniofacial development requires further longitudinal studies.

Craniofacial Morphology of Temporomandibular Disorder Patients with Different Disc Positions: Stratifying Features Based on Sex and Sagittal Skeletal Pattern.

Disc displacement (DD) appears in the majority of temporomandibular disorder (TMD) patients. The correlation between craniofacial morphology and different disc positions has been underlined, while the craniofacial morphological differences based on sex and sagittal skeletal pattern stratification have been insufficiently studied. In this study, 304 patients with TMD complaints were included and classified into normal position, disc displacement with reduction (DDwR) and disc displacement without reduction (DDwoR) groups according to magnetic resonance imaging. A total of 24 cephalometric measurements, covering the cranial base, vertical relationship, sagittal relationship, mandible position and morphology, and dental relationship, were assessed using lateral cephalograms. A stratified analysis was performed based on the sex and sagittal skeletal pattern. Overall, DD patients had distinctive craniofacial morphological features. The posterior cranial base length and mandibular arc angle were statistically different only in females, while the Y-axis angle, occlusal plane angle and sella nasion point A angle (SNA) might be unique features in males. Skeletal class II had the most statistically different measurements compared to the others. Differences in the Frankfort mandibular incisor angle (FMIA) and saddle angle were especially displayed in skeletal class III patients. The sex and skeletal sagittal pattern could affect the morphological differences in TMD patients with different disc positions.

Association of temporomandibular joint osteoarthrosis with dentoskeletal morphology in males: A cone-beam computed tomography and cephalometric analysis.

The objective of the study was to assess the differences in dentoskeletal morphology in males with and without temporomandibular joint osteoarthrosis (TMJOA). Three hundred seventy-one male participants seeking orthodontic treatment were enrolled in this cross-sectional study. Each participant's osseous status was evaluated using cone-beam computed tomography (CBCT) and classified into normal (N=104), indeterminate for TMJOA (N=110) and TMJOA (N=157) groups. The dentoskeletal characteristics were evaluated using cephalograms. Stratified analysis was performed based on age and skeletal pattern. Descriptive statistics and one-way analysis of variance were performed to investigate dentoskeletal differences among groups. P < .05 was considered statistically significant. The differences in posterior cranial base length, FMA, MP-OP, anterior facial height, articular angle, ramus height and L1-MP were statistically significant. After stratification by age, the differences in FMA, maxillomandibular angle, posterior facial height, facial height ratio, gonial angle and mandibular body length were statistically significant in adults. No statistical difference except for articular angle was observed in adolescents. After stratification by skeletal pattern, statistical differences were mainly apparent in skeletal Class II adults. Males with TMJOA showed a posteriorly positioned and backward-rotated mandible, especially in skeletal Class II adults. Compared with women, the craniofacial morphology of men is less affected by TMJOA. The association between TMJOA and craniofacial morphology also varied across different age groups and skeletal patterns. Prospective studies are required to clarify the cause-effect relationship between TMJOA and craniofacial morphology in males.

Craniofacial morphology of patients with unilateral cleft lip and palate at two stages of skeletal maturation.

The aim of this retrospective cross-sectional investigation was to perform a 3D analysis of craniofacial morphology of patients with unilateral cleft lip and palate (UCLP) at two stages of skeletal maturation. Cone-beam computed tomography (CBCT) scans of 52 UCLP patients (34 prepubertal; 18 pubertal) were collected from an outpatient referral center for the treatment of craniofacial deformities. In total 15 multiplanar craniofacial landmarks were identified, 3D virtual surface models were created, and 13 variables were measured to assess the 3D Euclidean distances between landmarks and spatial position of the landmarks in the projected X, Y and Z components. Maxillary and mandibular pitch (clockwise, counterclockwise) rotation relative to the cranial base was also evaluated. The significance level was set at 5%. Maxillary retrusion value relative to the cranial base was higher and statistically significant greater (p = 0.028) in pubertal (SNA, 77.4° ± 6.2; N-ANS Y, 3.3 mm ± 3.1) than in prepubertal patients (SNA 81.0° ± 5.2; N-ANS Y, 5.8 mm ± 2.7). The posterior cranial base length (S-Ba Y) was significantly longer (p = 0.013) in pubertal (20.7 mm ± 3.4) than in prepubertal patients (18.4 mm ± 2.7). The upper facial height (N-ANS Z) was significantly greater (p = 0.01) in pubertal (46.9 mm ± 4.5) than in prepubertal patients (43.4 mm ± 3.0). Prepubertal and pubertal UCLP patients presented distinct patterns of craniofacial morphology, mainly in the sagittal component of the maxilla and in the posterior cranial base length. Pubertal patients had greater maxillary retrusion and posterior cranial base length.

The Association between Cranial Base and Maxillomandibular Sagittal and Transverse Relationship: A CBCT Study

The cranial base has a crucial effect on the position of the maxilla and mandible. This study aims to investigate the relationship between the cranial base sagittal and transverse dimensions in different skeletal patterns. This is a retrospective study of pre-existing CBCT images of 132 subjects (60 males and 72 females) from Saudi Arabia with a mean age of 35 years old. The grouping of the subjects was based on the ANB angle of Steiner’s analysis. One-way ANOVA was used to compare the means of the sagittal and transverse dimensions between different skeletal patterns, followed by a post hoc test for individual comparisons. Logistic regression analysis was performed to test the relationship between gender, age, and cephalometric values between the three groups. The significance level was 0.05. One-way ANOVA revealed a statistically significant difference in posterior cranial base length (p &lt; 0.05) and total cranial base length (p &lt; 0.05) among different skeletal patterns. Tukey’s post hoc analysis showed that skeletal class II had a smaller posterior cranial base and total cranial base length when compared to the other groups. The class II skeletal pattern has a smaller posterior cranial base and total cranial base when compared to skeletal class I and class III skeletal patterns.

Craniofacial development in patients of Tessier No.0 cleft with a bifid nose using 3D computed tomography.

ObjectiveConsiderable studies have focused mainly on the facial deformity of Tessier No.0 cleft with a bifid nose, but the deformity of the skull is not well understood. Therefore, our study aimed to explore the evolution of cranial dysmorphology and the chronology of Tessier No.0 cleft with a bifid nose, by three-dimensional measurements.MethodsNinety-six non-surgical patients and computed tomographic scans were included (Tessier No.0 cleft with a bifid nose, n = 48; controls, n = 48) and divided into five age subgroups. Craniofacial cephalometric measurements were analyzed by Mimics software.ResultsThe widening of nasal bone was the most remarkable and persistent from 2 years old appropriately. The overall cranial base length in patients compared with controls increased 11.8% (p < 0.01) on average. The middle and posterior cranial fossa increasing accounted for most of this change. The cranial base angles also showed increased obviously. By analyzing the linear of the nasopharynx and respiratory tract, it was found that its development did not affect respiration.ConclusionsThe cranial base deformity of Tessier No.0 cleft with a bifid nose consists of the whole skull base and particularly the middle and posterior cranial base length increase. At the same time, there may be late closure of the spheno-occipital synchondrosis and sella displacement. We believe this study is unique in providing valuable data for elucidating the pathological and morphological abnormalities of skull base development in Tessier No.0 cleft with a bifid nose.

Cranial base measurements in different anteroposterior skeletal relationships using Bjork-Jarabak analysis.

To assess the linear and angular cranial base measurements (Bjork polygon) in different anteroposterior (AP) skeletal relationships using Bjork-Jarabak analysis. Pretreatment lateral cephalograms of 288 (146 women, 142 men, mean ages 21.24 ± 2.72 years and 22.94 ± 3.28 years, respectively) adult patients were divided into Class I, II, and III skeletal relationships according to their ANB angle. Linear and angular measurements of Bjork polygon were measured and compared among different skeletal relationships. Analysis of variance was performed to detect the differences among groups. Independent-sample t-test was used to detect differences between men and women. The Class II skeletal relationship has a significantly larger saddle angle than Class III does (P < .05), whereas Class III has a significantly larger gonial angle than Class II does (P < .05). The articular angle and sum of Bjork polygon angles were not significantly different among groups (P > .05). Anterior (N-S) and posterior (S-Ar) cranial base lengths were similar in the different AP skeletal relationships (P > .05). The ramal height and body of the mandible length were significantly larger in Class III compared with Class I and II (P < .05). Women had a significantly larger articular angle than men did (P < .05), although men had significantly larger linear measurements of Bjork polygon than women did (P < .05). The Class III skeletal relationship has a smaller saddle angle and larger mandibular length and gonial angle. Men have a larger cranial base and mandibular linear measurements and a smaller articular angle compared with women.

COMPARISON OF TWO CRANIAL BASE LENGTHS AND FOUR ANGLES AMONG THREE SAGITTAL SKELETAL BASES IN ADULT POPULATION OF DISTRICT PESHAWAR, PAKISTAN

Background: Research has shown that cranial base length, flexure and inclination play a role in the skeletal malocclusion in sagittal and vertical dimensions. The objectives of this study were to compare the two cranial base lengths and four angles among three sagittal skeletal bases in adult population of district Peshawar, Pakistan. Material &amp; Methods: This cross-sectional study was conducted in the Department of Orthodontics, Khyber College of Dentistry, Peshawar, Pakistan from February 2020 to March, 2020. Ninety lateral cephalograms were selected for the year 2019 from the database of department, with 30 from each group; Skeletal Class I, II and III. SN length (mm), SBa length (mm), N-S-Ba, N-S-Ar, SN-FH and SBa-FH were our ratio variables and were described by mean, range and SD with 95% CI for mean. Twelve hypotheses were tested each by one-way ANOVA and when it showed significant difference, then by post hoc Dunnett’s t test. Results: Results: The sample included 90 cephalograms; 30 each in Class I, II and III, including 38 men and 52 women with mean age 22.54±5.70 years. SN length (mm) was similar in Class II 68.1±2.15 and Class III 68.7±2.01 to Class I (control) 68.4±1.56 (p=.487). SBa length was similar in Class II 45.5±2.48 and Class III 44.9±2.23 to Class I 44.6±1.76 (p=.281). N-S-Ba angle was similar in Class II 126.7o±2.26 and Class III 127.3o±2.70 to Class I 127.1o±2.22 (p=.614). N-S-Ar angle was significantly greater (p&lt;.0001) in Class II 128.2o±2.45 than Class I 123.3o±1.97, and significantly greater (p=.030) in Class III 124.6o±1.70 than Class I. SN-FH angle was similar (p=.193) in Class II 7.9o±1.32 to Class I 7.4o±1.40 and similar (p=.356) in Class III 7.0o±0.94 to Class I. SBa-FH angle was similar in Class II 57.3o±2.19 and Class III 56.8o±1.45 to Class I 56.1o±1.90 (p=.058). Conclusions: Anterior cranial base length (SN length), posterior cranial base length (SBa length), N-S-Ba angle, SN-FH angle and SBa-FH angle were similar in Skeletal Class II to Class I and in Class III to Class I. N-S-Ar angle was greater in Skeletal Class II than Class I and in Class III than Class 1.

Comparison of Cephalometric Measurements of On-Screen Images by CephX Software and Hard-Copy Printouts by Conventional Manual Tracing

Newer diagnostic methods have become widespread in medicine nowadays as a result of extraordinary advancements in the field of electronics. On computers, various orthodontic programs are available as software. When it comes to orthodontics, diagnosis is critical, with the radiographic study being the most important phase. The goal of this research was to assess the level of liability of direct digital radiograph tracing using CephX and compare with hand tracing digital printouts and evaluate the two techniques concerning measurement reproducibility of individual methods. The material consisted of 25 digital lateral cephalometric images, fourteen linear and angular parameters were measured by a single operator digitally and manually. The intraclass correlation coefficient and confidence interval were used to compare the difference of the measurements obtained from manual and digital tracings, and intra-examiner error was evaluated by the coefficient of variation. A comparison of hand and CephX tracing showed a low level of agreement in the anterior facial height, anterior and posterior cranial base length. Only of (LI to A-Pog) line for both manual and digital methods showed poor intra-examiner duplicability. Thus, it can be concluded that digital tracing with CephX is adequate for clinical uses and similar to manual cephalometric tracings.

Correlations between mandibular ramus height and occlusal planes in Han Chinese individuals with normal occlusion: A cross-sectional study

Objectives: The objective of the study is to determine the relationships between ramus height and occlusal planes (OPs) in Han Chinese individuals with normal occlusion. Materials and Methods: Two hundred and four participants with normal occlusion were included and their cephalograms were analyzed. The ramus height (Ar-Go), Frankfort horizontal plane-posterior OP (FH-POP), FH-anterior OP (FH-AOP) and FH-OP, anterior and posterior cranial base length, SNA, SNB, ANB, Frankfort-mandibular plane angle, SN-MP, jaw angle, and mandibular body length were measured on the subjects’ cephalograms. Pearson correlation coefficients were calculated among continuous variables. The ramus height was considered as dependent variable and the OPs as independent variables. Age, sex, and other cephalometric parameters were considered as possible confounding factors. Univariate and multivariate analyses were performed to determine whether the relationships were significant. Results: The FH-POP and FH-OP were moderately associated with ramus height, while the FH-AOP showed a weak association (P &lt; 0.001). After adjusting age and sex, FH-POP, FH-AOP, and FH-OP showed significant negative associations with ramus height (β = −0.36, −0.28, and −0.37, respectively, P &lt; 0.001). The OP flattened with the ramus height increased. After adjusting all the confounding factors, FH-POP and FH-OP showed significant negative associations with ramus height. The ramus height increased by 0.19 mm/1° flattening of FHPOP (β = −0.19, P = 0.002). Conclusion: After adjust age, sex, and other possible confounding factors, the FH-POP and FH-OP were associated with the ramus height. The flattening of FH-POP was associated with the increase of ramus height. The results should be treated with caution since it’s a cross-sectional study.

Cranial Base Angle in Patients With Cleft Lip and Palate-A Systematic Review and Meta-Analysis.

Background: Diverse findings have been reported for the cranial base angle (CBA) in patients with CLP (cleft lip and palate) and non-CLP controls. Objective: The aim of this study is to assess and evaluate the CBA in patients with CLP and non-CLP controls. Methods: Data from PubMed, OVID Technologies, Inc., Cochrane, Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS), Scopus, Web of Science, and EMBASE for Excerpta Medica dataBASE (EMBASE) with relevant terms was extracted until December 31, 2020. Inclusion criteria were data of patients with non-syndromic unilateral cleft lip and palate (UCLP) and bilateral cleft lip and palate (BCLP). In the case of UCLP and BCLP, patients with craniofacial syndromes were excluded. The study proposal was registered with PROSPERO (Registration number: CRD42021228632). Results: Fifteen studies with a total of 2032 participants were included for the systematic review and 14 studies with a total of 1972 participants were included for the meta-analysis. The risk of bias was assessed using the Modified Newcastle Ottawa scale under seven domains by two authors. Thirteen studies were graded as "good" and two as "satisfactory." The CBA in patients with CLP were greater than the non CLP Class I controls in six of the 15 studies. CBA was greater in patients with CLP than non-CLP controls by 1.21° (95% CI of 0.19-2.22). Meta-analysis reported considerable heterogeneity (I2 = 86%). Anterior (ACB) and posterior cranial base (PCB) lengths were shorter in patients with CLP than in the non-cleft Class I controls by 2.14 mm (95% CI of 0.99-3.30) and 2.06 mm (95% CI of 1.52-2.60), respectively. Conclusion: Most studies were graded as good. Patients with CLP had greater CBA and shorter ACB and PCB lengths when compared to non-CLP controls.

Cephalocranial Disproportionate Fossa Volume and Normal Skull Base Angle in Pfeiffer Syndrome.

Pfeiffer syndrome is a rare syndromic craniosynostosis disorder, with a wide range of clinical manifestations. This study aims to investigate the structural abnormalities of cranial fossa and skull base development in Pfeiffer patients, to provide an anatomic basis for surgical interventions. Thirty preoperative CT scans of Pfeiffer syndrome patients were compared to 35 normal controls. Subgroup comparisons, related to differing suture synostosis, were performed. Overall, the volume of anterior and middle cranial fossae in Pfeiffer patients were increased by 31% (P < 0.001) and 19% (P = 0.004), versus controls. Volume of the posterior fossa in Pfeiffer patients was reduced by 14% (P = 0.026). When only associated with bicoronal synostosis, Pfeiffer syndrome patients developed enlarged anterior (68%, P = 0.001) and middle (40%, P = 0.031) fossae. However, sagittal synostosis cases only developed an enlarged anterior fossa (47%, P < 0.001). The patients with solely bilateral squamosal synostosis, developed simultaneous reduced anterior, middle and posterior cranial fossae volume (all P ≤ 0.002). The overall skull base angulation, measured on both intracranial and subcranial surfaces, grew normally. Enlarged anterior cranial fossae in Pfeiffer syndrome children is evident, except for the squamosal synostosis cases which developed reduced volume in all fossae. Volume of the middle cranial fossa is influenced by associated cranial vault suture synostosis, specifically, sagittal synostosis cases develop normal middle fossa volume, while the bicoronal cases develop increased middle fossa volume. Posterior cranial fossa development is restricted by shortened posterior cranial base length. Surgical intervention in Pfeiffer syndrome patients optimally should be indexed to different suture synostosis.

Craniofacial morphology in down syndrome: a systematic review and meta-analysis.

The aim of this study was to evaluate the craniofacial cephalometric characteristics of individuals with Down syndrome (DS), comparing them with healthy subjects. An electronic search was made in Pubmed, Embase, Lilacs, Scopus, Medline and Web of Science without imposing limitations on publication date or language. Studies were selecting following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. The PECO acronym was applied as follows: P (population), individuals with DS; E, (exposition) diagnosis of DS; C (comparison), individuals without DS; O (outcomes) craniofacial characteristics based on cephalometric measurements. Independent reviewers performed data extraction and assessed the methodological quality of the articles using the Newcastle–Ottawa Quality-Assessment-scale. Seven case–control studies were included in meta-analysis. Given the variability of the cephalometric measurements used, only those that had been reported in at least three or more works could be included. Anterior cranial base length (SN), posterior cranial base length (SBa), total cranial base length (BaN), effective length of the maxilla (CoA), sagittal relationship between subspinale and supramentale (ANB), anterior facial height (NMe), and posterior facial height (SGo) values were significantly lower in the DS population than among control subjects. No significant differences were found in sagittal position of subspinale relative to cranial base (SNA) and sagittal position of supramentale relative to cranial base (SNB). Summarizing, individuals with DS present a shorter and flatter cranial base than the general population, an upper jaw of reduced sagittal dimension, as well as a tendency toward prognatic profile, with the medium third of the face flattened and a reduced anterior and posterior facial heights.

Relationship between vertical components of maxillary molar and craniofacial frame in normal occlusion: cephalometric calibration on the vertical axis of coordinates.

ObjectiveThe aim of this study was to evaluate the correlation between the vertical position of maxillary first molar and vertical skeletal measurements in lateral cephalograms by using new linear measurements on the vertical axis of coordinates with calibration.MethodsThe vertical position of maxillary first molar (U6-SN), and the conventionally used variables (ConV) and the newly derived linear variables (NwLin) for vertical skeletal patterns were measured in the lateral cephalograms of 103 Korean adults with normal occlusions. Pearson correlation analyses and multiple linear regression analyses were performed with and without calibration using the anterior and posterior cranial base (ACB and PCB, respectively) lengths to identify variables related to U6-SN.ResultsThe PCB-calibrated statistics showed the best power of explanation. ConV indicating skeletal hyperdivergency was significantly correlated with U6-SN. Six NwLin regarding the position of palatal plane were positively correlated with U6-SN. Each multiple linear regression analysis generated a two-variable model sella and nasion to palatal plane. Among the three models, the PCB-calibrated model yielded highest adjusted R2 value, 0.880.ConclusionsU6-SN could be determined by the vertical position of the maxilla, which could then be used to plan the amount of molar intrusion and estimate its clinical stability. Cephalometric calibration on the vertical axis of coordinates by using PCB for vertical linear measurements could strengthen the analysis itself.

Evaluation of craniofacial morphology in short-statured children: growth hormone deficiency versus idiopathic short stature.

BackgroundShort stature is defined as a height below the 3rd percentile or more than two standard deviations below the mean for a given age, sex, and population. There have been inconsistent results regarding craniofacial morphology in short-statured children. This study aimed to analyze the differences between short-statured children with growth hormone deficiency, idiopathic short-statured children, and normal children.MethodsThirty-one short-statured children with growth hormone deficiency, 32 idiopathic short-statured children, and 32 healthy children were enrolled in this study. The measurements of their craniofacial structures from lateral cephalograms were evaluated.ResultsThere were statistically significant differences among the three groups seven variables (anterior cranial base length, posterior cranial base length, total cranial base length, upper posterior facial height, posterior total facial height, mandibular ramus length, and overall mandibular length) in the linear measurement and five variables (saddle angle, gonial angle, mandibular plane angle, position of mandible, and maxilla versus mandible) in the angular measurement.ConclusionCompared to the control group, many linear and angular measurements of the craniofacial structures were significantly different in the two short-statured groups (p<0.05). Treatment plans by orthodontists should include these craniofacial structure characteristics.

Evaluation of Cranial Base Morphology of Pakistani Population in Skeletal Class I, II and III Malocclusions

Introduction: Cranial Base integrate different patterns of growth in various regions of the skull such as the nasal cavity, the oral cavity, and the pharynx. Anteroposterior jaw position is thought to be affected by cranial base growth. Although scientific literature shows conflicting results regarding both positive and negative correlation between the cranial base and skeletal malocclusions.&#x0D; Materials &amp; Method: 138 patients selected according to the Inclusion criteria were divided into three major categories depending upon ANB angle. Class I, class II group and class III group. Pretreatment lateral cephalometric radiographs were taken. Linear and Angular measurements were measured. All the data was entered in SPSS version 25 and then analyzed by using descriptive statistics including mean, standard deviation and by using inferential statistics including Pearson correlation and ANOVA test.&#x0D; Result: No significant differences were recorded between cranial base deflection angles (N-S-Ar and N-S-Ba) and malocclusions groups while Anterior cranial base length S-N was found to be maximum in class III and posterior cranial base length S-Ba was greater in class I.&#x0D; Conclusion: Cranial base angles N-S-Ar and N-S-Ba did not demonstrate any statistically significant correlation with three malocclusion groups i.e. Class I, Class II and Class III and their correlation was negative.

Mandibular Spatial Reorientation and Morphological Alteration of Crouzon and Apert Syndrome.

From infancy to adulthood, the mandible develops increased ramus height, prominence of the chin, and laterally widened gonial angles. In Crouzon and Apert syndromes, both relative retrognathia and prognathic jaws have been reported. Growth is influenced by a variety of factors, including the growth and relative position of the skull base, functional coordination, and the spatial influence of the laryngopharynx. Thus, this study aimed to explore in detail the evolution of the mandible in both syndromes and its relationship with the entire facial structure and skull base. One hundred twenty-three preoperative computed tomographic scans (Crouzon, n = 36; Apert, n = 33; control, n = 54) were included and divided into 5 age subgroups. Computed tomographic scans were measured using Materialise software. Cephalometrics relating to the mandible, facial structures, and cranial base were collected. Statistical analyses were performed using t test and statistical power analysis. In Crouzon syndrome, the angle between the cranial base and gnathion was increased prior to 6 months of age by 10.29 degrees (P < 0.001) and by adulthood to 11.95 degrees (P = 0.003) compared with normal. After 6 months of age, the distance between bilateral mandibular condylions (COR-COL) was narrower by 15% (P < 0.001) in Crouzon syndrome compared with control subjects. Before 6 months of age, Apert COR-COL decreased 16% (P < 0.001) compared with control subjects and 13% (P = 0.006) narrower than Crouzon. During 2 to 6 years of age, Apert mandibular ramus height caught up to, and became longer than, Crouzon by 12% (P = 0.011). The nasion-sella-articulare angle of the Apert skull was 5.04 degrees (P < 0.001) less than Crouzon overall. In Crouzon syndrome, the changes of the spatial relationship of the mandible to the cranial base develop earlier than the mandibular shape deformity, whereas in Apert syndrome, the spatial and morphological changes are synchronous. The morphological changes of the mandible are disproportional in 3 directions, initially significant shortening of the mandibular width and length, and, subsequently, reduced height. Crouzon has more shortening in mandibular height compared with Apert, reflecting the more shortened posterior cranial base length. The narrowed angle between the mandible and the posterior cranial base in Apert skulls is consistent with the more limited nasopharyngeal and oropharyngeal airway space.

Variation of Cranial Base Morphology among Different Sagittal Skeletal Malocclusion – A Cephalometric Study in Nepalese Population

Introduction: Variation of cranial base morphology among different sagittal skeletal malocclusion has been evaluated previously by many studies. However, the findings of these studies conducted in different population differ due to racial/ ethnic differences. Objective: To obtain measurement data for various cranial base parameters and evaluate the variation in cranial base morphology among different sagittal skeletal malocclusion in Nepalese population. Materials and Methods: Manual tracing and measurement of 4 different cranial base parameters [linear- Anterior Cranial Base Length (ACBL), Posterior Cranial Base Length (PCBL) and Total Cranial Base Length (TCBL); angular - Cranial Base Angle (CBA)] were done on 90 pretreatment lateral cephalogram of healthy adult orthodontic patients. Study samples were matched for age and were equally distributed among three different sagittal skeletal malocclusion group using ANB angle. [skeletal Class I: 30, skeletal Class II: 30 and skeletal Class III: 30]. Analysis Of Variances [ANOVA] followed by Least Significant Difference (LSD) post hoc test was used to determine difference in cranial base measurements among three sagittal skeletal group. Results: While comparing the cranial base parameters among different sagittal skeletal class, mean value for all the parameters reduced systematically from skeletal Class II, via skeletal Class I, to skeletal Class III group. However, a statistically significant difference was found only for TCBL between skeletal Class II and skeletal Class III (p &lt; 0.01). Conclusions: A significant difference in TCBL among different sagittal skeletal malocclusion was observed in Nepalese adults.