Sella Nasion Research Articles

Cephalometric differences in grades II and IV adenoid hypertrophy: A cross-sectional study.

This study aims to determine whether there were cephalometric changes between grades II and IV adenoid hypertrophy. A cross-sectional study was conducted on 120 6-12-year-old patients selected from the ear, nose, and throat department at Imam Al-Hussein Medical City in Karbala. Patients were classified into three groups (each = 40) based on endoscopic findings: control, grade II, and grade IV. The findings were confirmed with cephalometric radiographs. Specific cephalometric points were identified to measure sella-nasion-point A (SNA), sella-nasion-point B (SNB), point A-nasion-point B (ANB), sella-nasion-pogonion (SNPog), sella nasion plane-palatal plane (SNPP), palatal plane-mandibular plane (PPMP), sella nasion plane-mandibular plane (SNMP), saddle, articular, gonial angles, and the y-axis. Additionally, superior-posterior airway space (SPAS), posterior air way space (PAS), mandibular plane-hyoid bone (MP-H), third cervical vertebra-hyoid bone (C3-H), total anterior facial height (TAFH), total posterior facial height (TPFH), upper anterior facial height (UAFH), lower anterior facial height (LAFH), and the Jarabak ratio were measured. Analysis of variance (ANOVA) and Welch tests indicated statistically significant differences (P < 0.05) among the three groups in SNA, SNB, SNPog, PPMP, SNMP, gonial angle, y-axis, SPAS, PAS, MP-H, and the Jarabak ratio. Tukey's honestly significant difference (HSD) and Games-Howell tests indicated a statistically significant difference between grade II and grade IV in SNA, SNMP, y-axis, SPAS, PAS, MP-H, and Jarabak ratio. The present study demonstrated that craniofacial changes start to occur at the moderate adenoid enlargement throughout the downward backward mandibular rotation. More changes would become evident at the severe stage; therefore, an urgent medical intervention and the establishment of nasal breathing by orthodontic treatment with breathing activity would be needed.

Prediction on the chin advancement of the twin block functional appliance in growing Chinese patients using the cephalometric markers: a retrospective study.

In spite of the widespread use of functional appliances, broad variations were applied the treatment response. The aim of this study is to investigate the pre-treatment cephalometric predictors on the chin advancement of twin-block in growing Chinese patients with class II malocclusion. After screening, 90 patients treated by twin-block were included in the study. The treatment outcome was assessed by the alterations in the distance of skeletal pogonion (Pog) to the vertical reference plane perpendicular to the Frankfurt plane (ΔPog-VRP). Moreover, ΔPog-VRP was divided by the cranial growth indicated by the Nasion to Basion changes (ΔN-Ba) to minimize the growth discrepancy among individuals (adjΔPog-VRP). Patients with ΔPog-VRP/adjΔPog-VRP above the median value were categorized into good response group (GRG/adjGRG, N = 45), while the rest were poor response group (PRG/adjPRG, N = 45). Independent t-test was used to compare the pre-treatment cephalometric measurements between GRG/adjGRG and PRG/adjPRG. Stepwise multivariate regression models were used to determine the pre-treatment cephalometric predictors for the chin advancement. Generally, there were not any significant differences between GRG/adjGRG and PRG/adjPRG regarding age, gender and cervical stage before twin-block treatment. Patients from GRG had significantly reduced cephalometric measurements in the vertical dimensions, including ∠N-Go-Me, ∠Mandibular plane-Occlusal plane (∠MP-OP) and the sum of angles (p < 0.05) in comparison to PRG. When the individual growth was taken account, similar findings were observed. The patients from adjGRG had a significantly lower ∠Sella Nasion line-MP (∠SN-MP), ∠Ar-Go-Me and ∠N-Go-Me, as well as an increased Posterior facial height (PFH)/Anterior facial height (AFH) (p < 0.05) compared with their counterparts. ∠N-Go-Me variable was the independent predictor on Pog advancement with (β = -0.26, 95% CI: -0.06 to -0.01, p = 0.01) and without (β = -0.29, 95% CI: -0.06 to -0.01, p < 0.01) adjustments on individual growth. The results of this study showed that patients with a reduced N-Go-Me angle are more likely to experience a greater chin advancement following twin-block treatment.

Clinical outcomes of gingivoperiosteoplasty for unilateral cleft lip and palate performed in early childhood

Conventional gingivoperiosteoplasty (GPP) performed during infancy adversely affects maxillary development. However, the outcomes of this procedure in early childhood have rarely been reported. Therefore, we examined the postoperative outcomes of GPP conducted in patients aged 1.5 years with unilateral cleft lip and palate (UCLP).This study included 87 non-syndromic patients with complete UCLP who had undergone early two-stage palatoplasty during the 1999–2004 period. The protocol comprised soft palate plasty at 1 year of age and hard palate closure at 1.5 years of age. In the GPP group (n=34), we introduced the GPP procedure during hard palate closure; in the non-GPP group (n=53), the labial side of the alveolar cleft remained intact. We examined computed tomography images taken at 8 years of age to observe bone formation at the alveolar cleft site. We also conducted cephalometric analysis to examine maxillary development at 12 years of age.Bone bridges at the alveolar cleft site were observed in 92% and 5.6% of the GPP and non-GPP groups, respectively. Moreover, 59% of the GPP group did not require secondary alveolar bone grafting (sABG), whereas all the patients in the non-GPP group underwent sABG. No statistically significant differences were noted in the maxillary anteroposterior length (GPP: 45.5±3.7mm, non-GPP: 45.9±3.5mm, p=0.67) and sella–nasion–point A angle (GPP: 75.6±4.5°, non-GPP: 73.8±12.6°, p=0.49).This study’s findings suggest that GPP performed at 1.5 years of age minimises the necessity of sABG and does not exert a negative influence on maxillofacial development.

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.

Evaluation of Glenoid Fossa Position in Class II Malocclusion Associated with Mandibular Retrusion and Class III Malocclusion Associated with Mandibular Protrusion

ABSTRACT Objective: This study examined the glenoid fossa in Class II and Class III malocclusions with mandibular retrusion and protrusion. Materials and Methods: A retrospective investigation examined 60 Class II and 60 Class III cephalometric radiographs. Cephalometric landmarks and glenoid fossa measurements were taken. Statistical analysis contrasted the two malocclusion groups’ glenoid fossas. Results: Class II malocclusion had a much lower mean Sella–Nasion–Condylion (SNCd) angle (glenoid fossa sagittal position) than Class III (14.6° ± 1.9). Class II malocclusion had a lower mean Sella–Nasion–Gonion (SNGo) angle (32.5° ± 4.3) than Class III (36.2° ± 3.9). The SNCd angle and SNGo angle in both groups demonstrated a negative correlation, demonstrating a relationship between the glenoid fossa and the mandibular sagittal axis. Conclusion: The glenoid fossa location differs significantly between Class II malocclusion with mandibular retrusion and Class III with protrusion. Class II malocclusion has a posterior glenoid fossa, while Class III has a less posterior one. Understanding these links may help patients receive more personalized treatment.

Dentoskeletal and soft-tissue changes concurrent to use of PowerScope appliance in treatment of Class II malocclusion – A retrospective study

Objectives: The most frequently encountered malocclusion in our daily clinical practice is Class II malocclusion with mandibular retrognathism. Treatment modalities for Class II malocclusion correction depend on numerous factors such as the severity of the malocclusion and the age at which the patient reports for the treatment. One of the innovations in Class II treatment is the PowerScope appliance. The objectives of this study were: (1) To evaluate dentoskeletal changes with the use of PowerScope appliance in the treatment of Class II division I malocclusion using lateral cephalograms in late adolescents. (2) To evaluate the soft-tissue changes with the use of PowerScope appliance in the treatment of Class II division I malocclusion using lateral cephalograms in late adolescents. Materials and Methods: This retrospective and cross-sectional study was done using pre- and post-treatment lateral cephalograms of 15 patients treated with PowerScope appliance who were under decelerated growth phase as assessed by cervical vertebrae maturation index (Stages 4, 5, and 6). All the lateral cephalograms were hand traced and measured by same investigator. Results: A highly statistically significant difference was observed between the pre-and post-angle formed by sella nasion plane and nasion to point B line (SNB), angle formed by nasion to point A line and nasion to point B line (ANB), condylion to point gnathion (Co–Gn), and distance between point A to nasion perpendicular (N perpendicular to Point A) to Pog skeletal parameters. It was found that a highly significant difference was noted for parameters upper molar to palatal plane (U6-PP), lower incisor to nasion to point B line (L1-NB), lower incisor to nasion to point B line (L1-NB*), lower incisor to mandibular plane angle (IMPA), and upper molar to pterygoid vertical line (U6-PTV). A significant difference was present for parameters upper incisor to nasion to point A line (U1-NA), while no difference was observed for upper incisor to sella nasion plane (U1-SN) and upper molar to pterygoid vertical line (U6-PTV). A significant statistical difference was observed between the pre-and post-lower lip to E line parameter. Conclusion: PowerScope caused significant skeletal changes by forward repositioning of the mandible as well as by an increase in the length of the mandible. There was significant retrusion of upper incisors and a highly significant increase in lower incisor protrusion, lower molar mesialization, and upper molar intrusion. Soft-tissue lower lip protrusion was significant.

Relationship of Occlusal Planes with Sella-Nasion and Frankfort Horizontal Planes in Different Skeletal Malocclusion. A Cephalometric Study

Objective: The objective of this study is to assess the relationship of anterior and posterior occlusal planes (AOP &amp; POP) with Sella-Nasion (SN) and Frankfort Horizontal (FH) planes in different skeletal malocclusion. Study Design and Setting: It was a cross-sectional study carried on 202 (40 males and 190 females) pretreatment lateral cephalogram of orthodontic patients of Jinnah Medical and Dental College, Karachi from June to September 2021. Methodology: The sample was divided into different skeletal pattern using ANB angle (Class I ANB 0-4°, Class II ANB&gt;4° and ANB Class III &lt;0°). The AOP and POP measured with respect to SN and FH planes in each class. Two way ANOVA was used to determine the relationship of occlusal planes among skeletal malocclusions. Results: 202 cephalogram, 40 males and 190 females were included in this study, out of which 102 (28 males and 102 females) were of class I, 88 (12 males and 76 females) were class II and 12 females were class III. Class II showed steeper SN-AOP and FH-POP than both Class I and Class III. There was statistically significant relationship between SN and AOP among all the three skeletal malocclusions (p&lt;0.005) and FH-AOP in class I and II (p&gt;0.025).While SN-POP and FH-POP were not statistically significant in all the three classes. Conclusions: Class II malocculsion showed steeper SN-AOP and FH-POP than Class I and Class III. POP to SN and FH were flatter in Class III.

Predictive Equation for Construction of Anatomic Porion with Machine Porion as Reference Point.

The aim of the study was to find a relationship between anatomic porion (PoA) and machine porion (PoM) and to construct PoA with the help of machine porion. About 200 pretreatment lateral roentgenic cephalograms were used for the study. Perpendicular distances of PoA and PoM were measured from Sella-Nasion (SN) plane and SN perpendicular plane. The results were tabulated. With the help of statistical analysis, predictive equation was derived to construct PoA and PoM. p-value was set at p < 0.05. Anatomic porion distance from SN was 24.35 ± 3.96 and from SN perpendicular was 12.89 ± 4.56. Distance of PoM from SN was 22.46 ± 4.20 and from SN perpendicular was 16.76 ± 4.89. Sexual dimorphism was also seen. There is a relationship between the PoM and PoA, thus, PoA, which is more reliable, can be constructed with the help of PoM, which is easy to reproduce. To overcome the inherent limitations of PoA and PoM, the present study aimed to find a relationship between the two so as to easily construct PoA that is more reliable while taking advantage of the ease of reproducibility of PoM.

Prevalence of Ectopic Canine in Different Sagittal and Vertical Skeletal Patterns.

The present investigation aims to find out the prevalence of ectopic canines among skeletal class I, II, and III malocclusions and to evaluate its variability among different genders and their growth patterns. The study sample included orthopantomograms (OPGs), lateral skull views, and study models of 999 patients collected from departmental archives. Among the selected samples, 258 were males and 738 were females. They were divided into skeletal class I, II, and III malocclusions sagittally and hypodivergent, normodivergent, and hyperdivergent groups according to their angle formed between point A-Nasion - point B (ANB) and angle formed between the Sella-Nasion (SN) plane and Gonion (Go) - Gnathion (Gn) plane (SnGoGn) values respectively. Of the 999 samples, 738 (73.9%) were female and 260 (25.8%) were male patients. When compared to men, females had a higher proportion of ectopic canines. An estimated 62.3% of skeletal class I, 29.1% of skeletal class II, and 8.6% of skeletal class III cases were found to have ectopic canines. An estimated 720 (72.1%) patients were found to have maxillary ectopic canines and out of the available sample, 474 patients have horizontal growth patterns, 335 have average growth patterns and 190 patients have vertical growth patterns. Labial impaction was the commonest (65.4%) followed by palatal (24.8%). Bilateral impaction was comparatively more (51.1%) than unilateral impaction (48.2%). Maxilla was more prevalent (72.1%) as compared to the mandible (16.3%) and for both the arches it was (11.6%). Ectopic canines were identified in a total of 62.3% of cases with skeletal class I, 29.1% of cases with skeletal class II, and 8.6% of cases with skeletal class III. The bilateral ectopic canine was mostly seen in skeletal class I and class III malocclusions, whereas, a unilateral presentation was mostly seen in skeletal class II malocclusions. Knowing the likelihood of a maxillary canine erupting ectopically will aid clinicians in starting with interceptive therapy since this condition necessitates complex orthodontic mechanics.

Vertical Facial Changes After 6 Months of Fixed Orthodontic Treatment

Background: The use of fixed orthodontic appliances can change the vertical face due to the movement of the molars. A lateral cephalometric radiograph was used to assess the outcome of the treatment. Analysis of the vertical facial changes was performed by observing the changes of the MP-SN angle. Objective: The purpose of this study was to determine whether there were differences in the vertical face before and after 6 months of fixed orthodontic treatment using the Steiner method. Methods: This study used a case-control design comparing groups before and after 6 months of fixed orthodontic treatment. The sample in this study amounted to 5 people. The vertical measurement of the face is carried out at the MP-SN angle, namely the angle formed by the MP (Mandibular Plane – Go-Gn) line and the SN (Sella-Nasion) line. The data analysis was performed with the program SPSS Version 25. Result: There were no significant changes in the study (p&gt;0.05). The average change is 1.2º. Of the 5 patients, 4 patients (80%) experienced a decrease in MP-SN angle, while 1 patient (20%) experienced an increase in the MP-SN angle. Conclusion: There was no significant change in facial vertical changes before and after 6 months of fixed orthodontic treatment at RSGM UMY. The decrease in the MP-SN angle is caused by the intrusion of the molars which causes the mandible to rotate counterclockwise. The increase in the MP-SN angle is due to the distalization of the molars, resulting in a clockwise rotation of the mandible.

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.

Correlation of Arch Width and Vertical Facial Morphology in Untreated Adults at a Tertiary Care Centre: A Cross-sectional Study

Introduction: The vertical dimension of a face is crucial in determining facial aesthetics and harmony. It is important for the orthodontist to understand the relationship between dental arch width and facial morphology for correct diagnosis and proper treatment plan. Aim: To determine the relationship between the vertical face pattern, dental arch width and also, to compare arch widths among both untreated female and male adults. Materials and Methods: This quantitative cross-sectional study was conducted in the Department of Orthodontics and Dentofacial Orthopaedics, at Sharad Pawar Dental College, Sawangi, Wardha, Maharashtra, India. The duration of the study was 1 month, from June 2019 to July 2019. Dental casts and lateral cephalograms were collected from 50 untreated adults (25 males and 25 females), aged between 18 to 30 years, who had minimal spacing, crowding and no crossbite. On every patient’s cephalogram, the angle between the plane of the mandible to the cranial base anterior Sella Nasion (SN) angle was calculated. Intercanine, intermolar, and interpremolar widths were measured on dental casts. Females and males arch width were compared. The significance of the differences was assessed using Student’s t-test, one-way Analysis of Variance (ANOVA) test and regression analysis. Results: The mean age of male study participants in the study was 24.44±5.04 years, whereas, mean age of females was 24.88±3.08 years. There were 25 males and 25 females of 18-30 years with mean age of 24 and 25 years, respectively. Arch widths of males were found to be significantly greater than, those of females (p&lt;0.05) and it was observed that, interarch width decreased significantly as the Sella Nasion-Mandibular Plane (SN-MP) angle increased. Regression analyses of male subjects revealed a significant positive relationship between the SN-MP angle. Whereas, the SN-MP angle and width of maxillary first premolar’s buccal cusp tip and the width of the second premolar (most buccal and buccal cusp tip), was found to have a strong correlation in female subjects. Conclusion: It was found that, the width of the dental arch is related to vertical face morphology and gender. During orthodontic therapy, it is recommended to use individualised archwires based on each individual’s pretreatment arch shape and width.

Assessment of soft- and hard-tissue changes following combined anterior segmental bi-jaw orthognathic surgery.

Anterior segmental Bi-jaw orthognathic surgery is indicated primarily for the correction of dentoalveolar protrusion. They are also indicated for correcting apertognathia, closing interproximal spaces between segments and can be incorporated with other osteotomies to obtain better results. The aim of this study was to analyze and compare the soft- and hard-tissue changes in patients who underwent combined anterior segmental bi-jaw orthognathic surgery. To compare and evaluate soft- and hard-tissue changes before and after combined anterior segmental bi-jaw orthognathic surgery by assessing (a) parameters in vertical dimension and (b) parameters in horizontal dimension and patient satisfaction was also assessed following surgery at 6 months' time interval. It is a prospective, single center and analytical study with sample size of 20 patients. It required routine setup for orthognathic surgery and manual tracing of lateral cephalograms. The surgical outcomes were assessed by hard tissue (Sella Nasion Point A (SNA) angle, Sella Nasion Point B (SNB) angle, Point A Nasion Point B (ANB) angle, NAPg, U1-NF, L1-MP angles; NA, NB, B-Pg, Nasion-Anterior nasal spine (N-ANS) distance, Anterior nasal spine-Gnathion (ANS-Gn) distance, and overjet and overbite) and soft tissue (facial convexity, NL, LM angles; LM fold, UL and LL protrusions, Upper lip length (ULL), Lower lip length (LLL), Sn-A, Si-B, Pg-Pg*, Ls-U1, Li-L1 distances, interlabial gap, and U1 exposure) variables pre and postsurgery. Descriptive statistics involved the mean and standard deviation, and recorded data were subjected to the statistical analysis using IBM SPSS 20 statistical package. The paired t-test, Pearson correlation coefficient were used. The level of significance P < 0.05 was taken as statistically significant and P < 0.01 as very significant. Overall improvement after surgery in both hard- and soft-tissue parameters was observed and significant changes were seen in every variable, except Si-B (P > 0.05). Correlations between soft- and hard-tissue changes were significant in both sagittal and vertical planes. Patients' satisfaction score showed that all patients had the high overall rate of satisfaction. Our study concludes that combined anterior segmental bimaxillary orthognathic surgery is a simple technique with minimal postoperative complications and limited relapse. The changes in facial esthetics and occlusion following orthognathic surgery depend highly on the stability achieved during the postoperative period.

Automated calibration system for length measurement of lateral cephalometry based on deep learning

Objective. Cephalometric analysis has been significantly facilitated by artificial intelligence (AI) in recent years. For digital cephalograms, linear measurements are conducted based on the length calibration process, which has not been automatized in current AI-based systems. Therefore, this study aimed to develop an automated calibration system for lateral cephalometry to conduct linear measurements more efficiently. Approach. This system was based on deep learning algorithms and medical priors of a stable structure, the anterior cranial base (Sella–Nasion). First, a two-stage cascade convolutional neural network was constructed based on 2860 cephalograms to locate sella, nasion, and 2 ruler points in regions of interest. Further, Sella–Nasion distance was applied to estimate the distance between ruler points, and then pixels size of cephalograms was attained for linear measurements. The accuracy of automated landmark localization, ruler length prediction, and linear measurement based on automated calibration was evaluated with statistical analysis. Main results. First, for AI-located points, 99.6% of S and 86% of N points deviated less than 2 mm from the ground truth, and 99% of ruler points deviated less than 0.3 mm from the ground truth. Also, this system correctly predicted the ruler length of 98.95% of samples. Based on automated calibration, 11 linear cephalometric measurements of the test set showed no difference from manual calibration (p > 0.05). Significance. This system was the first reported in the literature to conduct automated calibration with high accuracy and showed high potential for clinical application in cephalometric analysis.

Mandibular Torus as a New Index of Success for Mandibular Advancement Devices.

In obstructive sleep apnoea (OSA), treatment with mandibular advancement devices (MADs) reduces patients' Apnoea-Hypopnoea index (AHI) scores and improves their sleepiness and quality of life. MADs are non-invasive alternatives for patients who cannot tolerate traditional continuous positive airway pressure (CPAP) therapy. The variability of responses to these devices makes it necessary to search for predictors of success. The aim of our study was to evaluate the presence of mandibular torus as a predictor of MAD efficacy in OSA and to identify other potential cephalometric factors that could influence the response to treatment. This was a retrospective cohort study. The study included 103 patients diagnosed of OSA who met the criteria for initiation of treatment with MAD. Structural variables were collected (cephalometric and the presence or absence of mandibular torus). Statistical analysis was performed to evaluate the existence of predictive factors for the efficacy of MADs. A total of 103 patients who were consecutively referred for treatment with MAD were included (89.3% men); the mean age of the participants was 46.3 years, and the mean AHI before MAD was 31.4 (SD 16.2) and post- MAD 11.3 (SD 9.2). Thirty-three percent of patients had mandibular torus. Torus was associated with a better response (odds ratio (OR) = 2.854 (p = 0.035)) after adjustment for sex, age, body mass index (BMI; kg/m2), the angle formed by the occlusal plane to the sella-nasion plane (OCC plane to SN), overinjection, and smoking. No cephalometric predictors of efficacy were found that were predictive of MAD treatment success. The presence of a mandibular torus practically triples the probability of MAD success. This is the simplest examination with the greatest benefits in terms of the efficacy of MAD treatment for OSA.

Vertical Skeletal Changes after Extraction and Nonextraction Orthodontic Treatment.

Due to the constant battle regarding the controversial topic of orthodontic extraction, this study aims to assess the changes in vertical dimensions of patients treated with premolar extractions compared with nonextraction orthodontic patients. A sample of 60 borderline patients were recruited and divided into extraction and nonextraction groups. Eleven pretreatment cephalometric measurements were recorded using WebCeph and patients were followed-up until the completion of treatment. Intragroup and intergroup comparisons were made using paired t-test and two-sample independent t-test, respectively. The joint significance of differences was measured using F-tests. The intragroup comparison revealed that in the extraction group, the vertical dimension was significantly increased posttreatment for four cephalometric measurements, that is, mandibular plane angle (p < 0.05), palatal plane angle (p < 0.05), Frankfort mandibular plane angle (p < 0.05), and y-axis (p < 0.05). In the comparison of the posttreatment values of both groups, the mean differences of the posttreatment values for sella nasion (SN)-gonion (Go)-gnathion (Gn) angle (p = 0.008), the total anterior (p = 0.050), and lower anterior facial heights (AFH; p = 0.011) were significantly higher. At the same time, the Jarabak ratio was significantly (p = 0.006) lower in the extraction group than in the nonextraction group. The increase in vertical dimension is significantly higher in the extraction group than in the nonextraction group which indicates a significant impact of orthodontic extraction on the vertical dimensions.

Evaluation of Sagittal Change in the Maxilla and Incisor Inclination Following Rapid Palatal Expansion Using Cone Beam Computerized Tomography

Objective: To measure the sagittal changes in the maxilla via angular change in point A with Sella Nasion plane and incisor to palatal plane before (T1) and after (T2) rapid palatal expansion with bonded expander.&#x0D; Study Design: Quasi-experimental study.&#x0D; Place and Duration of Study: Armed Forces Institute of Dentistry Rawalpindi Pakistan, from Feb 2017 from Jan 2018.&#x0D; Methodology: 30 patients both male and female presenting to orthodontics department AFID between the ages of 9 and 12 years, with transverse maxillary deficiency were given a bonded hyrax appliance with an activation schedule of 2 turns per day, the retention period was 2 months followed by further retention with a removable plate. Two cone beam computerized tomography evaluations were done. One pre-expansion (T1) and the other after 2 months of retention (T2).&#x0D; Results: 30 children 16 males (53%) and 14 females (47%) with a mean age of 11.03 ± 0.76 years were studied showing that from pre-treatment to post-treatment Sella Nasion point A value changed insignificantly from 77.03 ± 2.81 to 77.2 ± 3.02and 1 to palatal plane changed insignificantly from 111.82 ± 5.74 to 110.8 ± 5.80. Paired sample t-test results confirmed the statistically insignificant change in Sella Nasion point A and 1to Palatal Plane.&#x0D; Conclusion: Following rapid palatal expansion with a bonded expander in growing patients the change in maxillary location in the sagittal dimension and the change in inclination of incisor to palatal plane following expansion was insignificantly affected statistically and hence clinically.

Effects of Class II elastics during growth on the functional occlusal plane according to skeletal pattern and extraction vs nonextraction.

To investigate the effect of Class II intermaxillary elastics on the functional occlusal plane (FOP) of growing patients. A total of 50 participants aged 11 to 16 years were selected from a university clinic archive >1-year after treatment and after undergoing 6 months of Class II elastic wear, taking pretreatment (T0) and posttreatment (T1) lateral cephalometric radiographs, and consenting to participate at recall (T2). Participants were divided into 3 groups according to skeletal pattern or into 2 groups according to treatment with extraction (E) or nonextraction (NE). Angular changes of FOP relative to the Sella-Nasion (SN), mandibular plane (MP), and Frankfort horizontal (FH) were compared within and between groups. A statistically significant reduction of FOP-SN/FH, but not of FOP-MP, was found from T0-T1-T2 when all patients were grouped together. FOP-SN/MP/FH was significantly the largest in the patients with a hyperdivergent skeletal pattern, but lowest in the patients with a hypodivergent skeletal pattern at T0, T1, and T2 (P < .032). FOP-MP at T0-T2 was statistically larger in group E than in group NE (P < .02). No differences were found for FOP changes (change before treatment minus after treatment and change after treatment minus 1 year after treatment) between different skeletal patterns (P > .433) and treatment groups (P > .193). Use of Class II elastics during the growth period was not found to show adverse effects on FOP rotation. Neither skeletal pattern nor treatment modality differed in the response to Class II elastics with regard to FOP changes. Individual patient growth pattern must be taken into consideration when treatment planning the use of Class II elastics. Orthodontists should take into account individual skeletal and growth patterns while using Class II elastics.

Evaluation of an automated superimposition method based on multiple landmarks for growing patients.

To determine if an automated superimposition method using six landmarks (Sella, Nasion, Porion, Orbitale, Basion, and Pterygoid) would be more suitable than the traditional Sella-Nasion (SN) method to evaluate growth changes. Serial lateral cephalograms at an average interval of 2.7 years were taken on 268 growing children who had not undergone orthodontic treatment. The T1 and T2 lateral images were manually traced. Three different superimposition methods: Björk's structural method, conventional SN, and the multiple landmark (ML) superimposition methods were applied. Bjork's structural method was used as the gold standard. Comparisons among the superimposition methods were carried out by measuring the linear distances between Anterior Nasal Spine, point A, point B, and Pogonion using each superimposition method. Multiple linear regression analysis was performed to identify factors that could affect the accuracy of the superimpositions. The ML superimposition method demonstrated smaller differences from Björk's method than the conventional SN method did. Greater differences among the cephalometric landmarks tested resulted when: the designated point was farther from the cranial base, the T1 age was older, and the more time elapsed between T1 and T2. From the results of this study in growing patients, the ML superimposition method seems to be more similar to Björk's structural method than the SN superimposition method. A major advantage of the ML method is likely to be that it can be applied automatically and may be just as reliable as manual superimposition methods.

Skeletal Stability of Two-Jaw Surgery Without Bone Grafting in Patients With Cleft Lip and Palate.

The purpose of this study was to evaluate the postoperative skeletal stability of orthognathic surgery performed without a bone graft in cleft lip and palate patients. Nineteen cleft lip and palate patients that underwent orthognathic surgery from July 2008 to August 2019 at the Department of Oral and Maxillofacial Surgery of Pusan National University Dental Hospital were selected. None of these patients underwent bone grafting during orthognathic surgery. Lateral cephalograms were taken 1 month before surgery (T0), immediately after surgery (T1), and 6 months after surgery (T2). Lateral cephalograms were analyzed using the V-Ceph program. The analysis was performed using SPSS for Windows version 26.0. The analysis was conducted by repeated-measures analysis of variance. A total of 19 patients were included in this retrospective study (9 males/10 females of overall mean age 22 ± 4.89 years). Mean maxillary depth values at the 3-time points were 85.37° ± 2.62° (T0), 90.13° ± 2.77° (T1), and 89.29° ± 2.91° (T2). Mean McNamara-N Perpend values were -5.52 ± 3.19 mm (T0), 0.09 ± 3.10 mm (T1), and -0.83 ± 3.14 mm (T2). Mean sella nasion point A (SNA) values were 75.42° ± 2.98° (T0), 79.19° ± 2.94° (T1), and 78.45° ± 2.84° (T2). Mean relapse rates were maxillary depth 20.15%, McNamara-N Perpend 17.95%, and SNA 18.74%. Mean horizontal advancement was 5.61 ± 2.32 mm based on McNamara vertical to A point, mean horizontal relapse was -0.92 ± 0.56 mm, and the mean horizontal relapse rate was 17.95%. Favorable skeletal stability can be obtained without bone graft when the amount of maxillary advancement is less than 6 mm in cleft patients.