SNA Angle Research Articles

Comparing the efficiency of maxillary protraction using digital cooperation monitoring in ages 4–7 and 8–11: a prospective study

Abstract Objectives This study compares the effectiveness of face mask therapy applied after rapid maxillary expansion (RME) in 4- to 11-year-old patients with objective co-operation data collected using thermal sensors. The null hypothesis was that there would be no difference in the effectiveness of the maxillary protraction. Materials and method Initial and post-treatment lateral cephalometric radiographs were taken of patients with maxillary retrognathia, aged between 4 to 7 years (6.1 ± 1.88, n = 13) and 8 to 11 years (9.4 ± 1, n = 12) of age. An RME was performed for at least 10 days. The face mask protraction force was set to 450 g per side, and the recommended usage was 10 hr per day. TheraMon® microsensors were integrated into the face mask. Results The daily usage was significantly higher in the younger age group (8.9 ± 1.8 hr) compared to the older group (7.1 ± 0.9 hr). The SNA angle, A-Nasionperp (mm), ANB angle, Wits (mm), maxillary depth, ANS-Me (mm), the molar relationship (mm) and overjet (mm) significantly increased in both groups. Co-A (mm), the saddle angle, articular angle and UL-E Line (mm) showed a significant increase only in the older group, while the L1-A/Pg decreased significantly. The SNB angle decreased significantly only in the younger group. There was no statistically significant difference in the delta values between the two groups. Conclusion The null hypothesis was partly rejected since no difference was observed in the examined skeletal and soft tissue parameters.

Correlation between cone-beam computed tomographic findings and the apnea-hypopnea index in obstructive sleep apnea patients: A cross-sectional study.

The aim of this study was to explore the correlations of cone-beam computed tomographic findings with the apnea-hypopnea index in patients with obstructive sleep apnea. Forty patients with obstructive sleep apnea were selected from the ear-nose-throat (ENT) outpatient clinic, Faculty of Medicine, Mansoura University. Cone-beam computed tomography was performed for each patient at the end of both inspiration and expiration. Polysomnography was carried out, and the apnea-hypopnea index was obtained. Linear measurements, including cross-sectional area and the SNA and SNB angles, were obtained. Four oral and maxillofacial radiologists categorized pharyngeal and retropalatal airway morphology and calculated the airway length and volume. Continuous data were tested for normality using the Kolmogorov-Smirnov test and reported as the mean and standard deviation or as the median and range. Categorical data were presented as numbers and percentages, and the significance level was set at P<0.05. The minimal value of the cross-sectional area, SNB angle, and airway morphology at the end of inspiration demonstrated a statistically significant association (P<0.05) with the apnea-hypopnea index, with excellent agreement. No statistically significant difference was found in the airway volume, other linear measurements, or retropalatal airway morphology. Cone-beam computed tomographic measurements in obstructive sleep apnea patients may be used as a supplement to a novel radiographic classification corresponding to the established clinical apnea-hypopnea index classification.

Anatomical and Physiological Changes Following Primary Palatoplasty Using "The Buccal Flap Approach".

The purpose of this study was to determine the anatomical differences among selected individuals with a cleft palate repaired using "The Buccal Flap Approach" during primary palatoplasty compared to aged-matched participants without cleft palate. Observational, prospective. Two regional hospitals. A total of 30 adult males consisting of 15 adults born with cleft palate who received the Double Opposing Z-Plasty plus Buccal Flaps (DOZP + BF) repair at the time of primary palatoplasty and no history of secondary speech surgery or orthognathic surgery and 15 adults without a history of cleft palate. All participants underwent MRI to visualize anatomy. Ten velopharyngeal and craniofacial anatomical measures. No statistically significant differences between groups were observed for velar thickness, velar length, pharyngeal depth, NSBa angle, SNB angle, or levator veli palatini length. Individuals with the DOZP + BF presented with a greater effective velar length (p < .001), greater effective VP ratio (p < .001), smaller SNA angle (p < .001), and smaller maximal velar stretch (p < .001) compared to the control participants. This study suggests that adult males who received the DOZP + BF repair at the time of primary palatoplasty and no history of secondary speech surgery or orthognathic surgery present with a longer effective velar length and larger effective VP ratio in comparison to the non-cleft group. Future research is needed to compare patients with and without favorable outcomes from multiple surgical types to fully understand how surgical techniques alter the anatomy.

Impact of relaxing incisions on maxillofacial growth following Sommerlad–Furlow modified technique in patients with isolated cleft palate: a preliminary comparative study

ObjectiveTo estimate the impact of relaxing incisions on maxillofacial growth following Sommerlad-Furlow modified technique in patients with isolated cleft palate.Study designA Retrospective Cohort Study.MethodsA total of 90 participants, 60 patients with non-syndromic isolated soft and hard cleft palate underwent primary palatoplasty (30 patients received the Sommerlad-Furlow modified technique without relaxing incision (S.F−RI group), and 30 received Sommerlad-Furlow modified technique with relaxing (S.F+RI group) with no significant difference found between them regarding the cleft type, cleft width, and age at repair. While the other 30 were healthy noncleft participants with skeletal class I pattern as a Control group. The control group (C group) was matched with the patient groups in number, age, and sex. All participants had lateral cephalometric radiographs at least 5 years old age. The lateral cephalometric radiographs were taken with the same equipment by the same experienced radiologist while the participants were in centric occlusion and a standardized upright position, with the transporionic axis and Frankfort horizontal plane parallel to the surface of the floor. A well-trained assessor (S. Elayah) used DOLPHIN Imaging Software to trace twice to eliminate measurement errors. All the study variables were measured using stable landmarks, including 12 linear and 10 angular variants.ResultsThe mean age at collection of cephalograms was 6.03 ± 0.80 in the S.F+RI group, 5.96 ± 0.76 in the S.F−RI group, and 5.91 ± 0.87 in the C group.Regarding cranial base, the results showed no statistically significant differences between the three groups in S–N and S–N-Ba. While the S.F+R.I group had a significantly shortest S-Ba than the S.F−R.I & C groups (P = 0.01 & P < 0.01), but there was no statistically significant difference between S.F−R.I & C groups (P = 0.71).Regarding the skeletal maxilla, there was no significant difference between the S.F+R.I and S.F−R.I groups in all linear measurements (N-ANS and S-PM) except Co-A, the S.F+R.I group had significantly shorter Co-A than the S.F−R.I & C groups (P = < 0.01). While the angular measurement, S.F+R.I group had significantly less SNA angle than the S.F−R.I & C groups (P = < 0.01).Regarding mandibular bone, there were no statistically significant differences in all linear and angular mandibular measurements between the S.F+R.I and S.F−R.I.groups.Regarding intermaxillary relation, the S.F+R.I group had significant differences in Co-Gn—Co-A and ANB compared to the S.F−R.I & C groups (P = < 0.01). While there was no statistically significant difference in PP-MP between the three groups.ConclusionAs a preliminary report, the Sommerlad-Furlow modified technique without relaxing incisions was found to have a good maxillary positioning in the face and a satisfactory intermaxillary relationship compared to the Sommerlad-Furlow modified technique with relaxing incisions.

A comparison of maxillofacial growth in Chinese children with isolated cleft palate treated with two different palatoplasty techniques without relaxing incisions: a preliminary study

ObjectiveTo assess the maxillofacial growth of patients with isolated cleft palate following the Sommerlad-Furlow modified technique and compare it with the effect of the Sommerlad technique.Study designA Retrospective Cohort Study.MethodsA total of 90 participants, 60 patients with non-syndromic isolated soft and hard cleft palate (ISHCP) underwent primary palatoplasty without relaxing incision (30 patients received the Sommerlad-Furlow modified (S-F) technique and 30 received Sommerlad (S) technique). While the other 30 were healthy noncleft participants with skeletal class I pattern (C group). All participants had lateral cephalometric radiographs at least 5 years old age. All the study variables were measured by using stable landmarks, including 11 linear and 9 angular variants.ResultsThe means age at collection of cephalograms were 6.03 ± 0.80 (5–7 yrs) in the S group, 5.96 ± 0.76 (5–7 yrs) in the S-F group, and 5.91 ± 0.87 (5–7 yrs) in the C group. Regarding cranial base, the results showed that there were no statistically significant differences between the three groups in S–N and S–N-Ba. The S group had a significantly shortest S-Ba than the S-F & C groups (P = 0.01), but there was no statistically significant difference between S-F and C groups (P = 0.80). Regarding skeletal maxillary growth, the S group had significantly shorter Co-A, S- PM and significantly less SNA angle than the C group (P = < 0.01). While there was no significant difference between S-F & C groups (P = 0.42). The S group had significantly more MP-SN inclination than the C group (P = < 0.01). Regarding skeletal mandibular growth, there were no statistically significant differences in all linear and angular mandibular measurements between the three groups, except Co-Gn of the S group had a significantly shorter length than the C group (P = 0.05). Regarding intermaxillary relation, the S-F group had no significant differences in Co-Gn—Co-A and ANB as compared with the C group. The S group had significantly less ANB angle than S-F & C groups (P = 0.01 & P = < 0.01). In addition, there were no significant differences in all angular occlusal measurements between the three groups.ConclusionAs a preliminary report, Sommerlad-Furlow modified technique showed that maxillary positioning in the face tended to be better, and the intermaxillary relationship was more satisfactory than that in Sommerlad technique when compared them in healthy noncleft participants.

Vertical and sagittal changes produced by an expander with differential opening and fan-type expander: A post-hoc analysis of a randomised controlled trial.

To compare the sagittal and vertical cephalometric effects in participants treated with an expander with differential opening (EDO) versus the fan-type expander (FE). Two-arm parallel randomised clinical trial (RCT). This study comprised cone-beam computed tomography-derived cephalometric images from 48 participants from a RCT. The sample was randomly allocated into two groups. The study was single-blinded. In total, 24 participants were treated with rapid maxillary expansion (RME) using EDO and 24 participants underwent RME using FE. The primary outcomes were the dentoskeletal vertical changes produced by RME. The secondary outcomes were the dentoskeletal sagittal changes. A cephalometric analysis was performed before treatment and 1 or 6 months after the active phase of RME using Dolphin Imaging Software. Intergroup comparisons of interphase changes were performed using the t-test and Mann-Whitney U test (P < 0.05). The final sample comprised 24 patients (11 men, 13 women; mean age = 7.6 ± 0.9 years) in the EDO group and 24 patients (10 men, 14 women; mean age = 7.8 ± 0.9 years) in the FE group. Both expanders produced a similar clockwise rotation of the mandible (FMA; mean difference [MD] = 0.09°, 95% confidence interval [CI] = -1.01 to 0.84). In the FE group, a greater increase of the SNA angle was observed after expansion compared to the EDO group (MD = 1.04°, 95% CI = -1.90 to -1.58). A greater palatal torque of maxillary incisors was observed in the FE group (MD = 1.32°, 95% CI = 0.05-2.56). Of the participants, 54% reported a little discomfort during the active phase of treatment and 46% of the participants did not report any discomfort. Both expanders produced similar vertical cephalometric changes. FEs caused slightly more maxillary anterior displacement after expansion with a compensatory palatal torque of the maxillary incisors compared to the EDOs. However, the amount of sagittal difference was not clinically relevant. The trial was registered at ClinicalTrials.gov, under the identifier NCT03705871.

Skeletal Pattern of Bangladeshi Patients with Class II Malocclusion Attending in a Selected Private Setting

Background: The term "Class II malocclusion" encompasses a range of dental and skeletal characteristics, making precise diagnosis and treatment planning challenging. This study aimed to examine 32 Bangladeshi patients with Class II malocclusion to evaluate maxillary and mandibular skeletal positions using cephalometric measurements commonly used in clinical practice. Methods: Study casts and lateral cephalograms of 32 patients (17 females and 15 males) with Class II malocclusion were analyzed. Inclusion criteria comprised Class II molar relationship, the absence of craniofacial deformities, and no previous orthodontic treatment. Cephalometric measurements included SNA, SNB, and ANB angles, and data were analyzed using SPSS software. Results: Among the patients, 53% exhibited maxillary skeletal protrusion, 43% had mandibular retrusion, and only 3.1% presented both maxillary protrusion and mandibular retrusion. Surprisingly, 31.2% showed maxillary skeletal retrusion, and 28.1% exhibited mandibular protrusion, highlighting the significant variation in skeletal patterns within this cohort. Conclusion: Our findings emphasize the diverse skeletal patterns present among Bangladeshi patients with Class II malocclusion. The implications of these variations for treatment planning are substantial, as the treatment approach may differ depending on the underlying skeletal pattern. Given this diversity, individualized assessment and tailored treatment strategies are essential to achieve optimal outcomes. While this study has provided valuable insights, future research with larger and more diverse samples is warranted to further explore these complex relationships. Update Dent. Coll. j: 2023; 13(2): 34-37

Impact of Mandibular Symphyseal Distraction Osteogenesis (MSDO) on the Sagittal Dimension and Long-Term Skeletal stability.

To evaluate the long-term effects of mandibular symphyseal distraction osteogenesis (MSDO) on the correction of class II malocclusion correction and dental crowding. Twenty-two patients received MSDO and presented class II malocclusion with transverse mandibular discrepancy. The authors collected data on 2 different cephalometric analyses. On Tweed analysis, The authors recorded ANB, SNA, SNB, and FMA angles. On Delaire analysis, we recorded the distance from Pti (pterygoid inferior) to ENAt (anterior nasal spine) and the distance from Cos (superior condyle) to Pog (pogonion). Superimpositions studies were performed at pre-treatment phase (T1) and post-treatment phase (T2) to evaluate the new position and changes in the dimensions of the mandible and maxilla. On superimposition of Tweed analysis of T1 and T2, reduction of ANB was seen in 18 patients, no change in ANB in 2 patients, and increase in ANB (by 1 deg) in 2 patients. Superimposition of Delaire analysis showed a mean difference of 0.3mm (SD, 3.6mm) between T1 and T2 for the maxilla and a mean difference of 6.0mm (SD, 7.3mm) for the mandible. Mandibular symphyseal distraction osteogenesis performed after the pubertal growth peak can effectively correct class II malocclusion and dental crowding with a single light surgical procedure.

New Method to Assess Sagittal Jaw Position: TWM and TWG Angles: A Cephalometric Study

Aim The aim of the study was to develop new cephalometric angles TWM (T-Tuberculum sella, W-wing point, M-maxillary point) and TWG (T-Tuberculum sella, W-wing point, G point-center of mandibular symphysis) and to assess and evaluate the newly developed angles in determining the maxillary and mandibular sagittal position, respectively. Materials and Methods Ninety pretreatment lateral cephalograms from the records of Department of Orthodontics and Dentofacial Orthopaedics were traced and divided equally into three groups as class I, class II, and class III based on cephalometric values of ANB angle and WITS appraisal. Further for each radiograph, angles such as SNA, TWM, SNB, and TWG were measured and recorded. The TWM angle (Maxilla) was formed using the points T-Tuberculum sella, W-wing point, M-maxillary point, and the TWG angle (mandible) was formed using the points T-Tuberculum sella, W-wing point, G point-center of mandibular symphysis. Results The mean values of TWM and TWG angles for the class I group were 120.1°± 3.6° and 101.4 ± 3.7°, respectively. The one-way analysis of variance (ANOVA) was used followed by Tukey post hoc testing to determine whether there was a statistically significant difference between the mean values of the three groups. A p value ≤ .05 was considered to be statistically significant. Pearson correlation test revealed a strong correlation between SNA and TWM angles and similarly between SNB and TWG angles. Conclusion The two new angles, TWM for maxilla and TWG for mandible established, can be used as an alternative for assessing the sagittal position of the jaw bases and will give a clearer picture, as stable and reproducible landmarks are used.

Mandibular autorotation revisited: A retrospective study of accuracy and stability of maxillary impaction in retrognathic patients with condylar osteoarthritis

The aim of this retrospective study was to evaluate the accuracy of maxillary positioning with mandibular autorotation using the straight locking miniplate (SLM) technique and computer-aided design/computer-aided manufacturing (CAD/CAM) wafers on postoperative stability in patients with skeletal class II malocclusion and condylar osteoarthritis. Cephalometric analysis of the maxillary position and MA center (ARC) before (T0), 3 days (T1), 3 months (T2), and 1 year (T3) after surgery was performed. Analysis of 21 patients revealed a mean movement of −2.0 ± 2.2 mm (x-axis) and 5.4 ± 2.4 mm (y-axis) at U1 and of −1.5 ± 2.4 mm (x-axis) and 4.9 ± 1.6 mm (y-axis) at U7. The SNA, SNB, ANB, and SN-MP angles and ramus inclination at T0 were significantly different from those at T1, T2, and T3. The distance from the ARC to the Co of T2 and T3 was significantly smaller than that of T1 on the x-axis, indicating that the ARC converged horizontally to Co. There was no significant difference in the amount of rotation at any time point. Accurate maxillary positioning with mandibular autorotation using SLM and CAD/CAM wafers may correct the unstable rotation axis of the mandible and prevent early postoperative relapse.

Cephalometric Evaluation of Age-dependent Craniofacial Skeletal Changes in Iranian Population with Class II Malocclusion: A Cross-sectional Study

Background: Class II malocclusion is one of the most prevalent occlusion discrepancies. Knowledge of growth changes in craniofacial components can help clinicians plan orthodontic treatment, determine the proper timing to initiate the treatment, and predict the treatment outcome, especially in growth modification protocols. This study evaluates craniofacial skeleton changes in class II malocclusion subjects compared to class I malocclusion. Methods: In this cross-sectional study, cephalograms of 858 individuals aged between 7 and 23 were investigated. The samples were divided into the class I group (ANB angle 0–4) and class II group (ANB angle≥4 degrees), including 426 and 432 cephalograms, respectively, and each group was divided into seven subgroups considering age. Cephalometric analysis was performed using OnyxCeph software, and statistical analyses of variance, mean, paired t test, and independent samples t test were performed using SPSS software. Results: The results showed no significant differences between class I and class II groups in variables related to the cranial base and vertical facial height. In class II groups, the SNA angle was significantly greater. The total mandibular height (Co-Gn), facial angle (Npog-FH), and SNB angle were significantly greater in class I compared to the class II group. Conclusion: Protrusion of the maxilla affects the formation of class II malocclusion, but an underdeveloped mandible is the main component of Class II malocclusion formation. With increasing age, especially after puberty, the mandible may become more retruded in class II patients.

Craniofacial Cephalometric Characteristics and Open Bite Deformity in Individuals with Amelogenesis Imperfecta-A Systematic Review and Meta-Analysis.

Individuals with amelogenesis imperfecta (AI) often present with malocclusions, especially a dental or skeletal anterior open bite (AOB). To evaluate the craniofacial characteristics in individuals with AI. A systematic literature search was conducted with the PubMed, Web of Science, Embase and Google Scholar databases to identify studies relating to the cephalometric characteristics of individuals with AI, without any language or publication date restrictions. The grey literature was searched using Google Scholar, Opengrey and Worldcat. Only studies with a suitable control group for comparison were included. Data extraction and a risk of bias assessment were carried out. A meta-analysis was performed using the random effects model for cephalometric variables that were evaluated in at least three studies. The initial literature search yielded 1857 articles. Following the removal of duplicates and a screening of the records, seven articles were included in the qualitative synthesis, representing a total of 242 individuals with AI. Four studies were included in the quantitative synthesis. The meta-analysis results showed that individuals with AI present a smaller SNB angle and larger ANB angle than those of control groups in the sagittal plane. In the vertical plane, those with AI present a smaller overbite and larger intermaxillary angle than those without AI. No statistically significant differences were found for the SNA angle when comparing the two groups. Individuals with AI seem to present with more vertical craniofacial growth, leading to an increased intermaxillary angle and decreased overbite. This possibly leads to a more retrognathic mandible with a larger ANB angle due to an anticipated posterior mandibular rotation.

Sagittal and Vertical Changes of the Maxilla after Surgically Assisted Rapid Palatal Expansion: A Systematic Review and Meta-Analysis.

Surgically assisted rapid palatal expansion (SARPE) is often performed to correct the transverse deficiency in the maxilla for skeletally mature patients. However, there is little consensus on the sagittal and vertical displacement of the maxilla after SARPE. This systematic review aims to analyze the position changes of the maxilla in the sagittal and vertical dimensions after the completion of SARPE. Registered with PROSPERO (registration number: CRD42022312103), this study complied with the 2020 PRISMA guideline and was conducted on 21 January 2023. Original studies were screened from MEDLINE (PubMed), Elsevier (SCOPUS), and Cochrane, and supplemented by hand-searching. Cephalometric changes of skeletal vertical and sagittal measurements were the focus. A fixed-effects model was applied in R for meta-analysis. After applying inclusion and exclusion criteria, seven articles were included in the final review. Four studies had a high risk of bias, and the other three had a medium risk of bias. Meta-analysis revealed that the SNA angle increased by 0.50° ± 0.08° (95% confidence interval, 0.33° to 0.66°), and the SN-PP angle increased by 0.60° ± 0.09° (95% confidence interval, 0.41° to 0.79°) after SARPE. In summary, the maxilla displayed statistically significant forward and clockwise downward movement after SARPE. However, the amounts were small and might not be clinically significant. Due to the high risk of bias of included studies, our results must be taken cautiously. Future studies are needed to discern the effects of direction and angulation of the osteotomies of SARPE on the displacement of the maxilla.

Long-term stability after high-pull headgear combined with fixed appliances: A retrospective cohort study of growing class II patients

High-pull headgear with fixed appliances is a common therapeutic plan in class II growing individuals, especially in those with a tendency to hyperdivergence. The stability of this approach has not been adequately assessed in the long-term. The aim of this retrospective study was to assess that long-term stability by means of lateral cephalograms. Seventy-four consecutive patients were included and examined at three time-points: pre-treatment (T1), end of treatment (T2), and at least five years post-treatment (T3). The average initial age of the sample was 9.3 years (standard deviation, SD: 1.6). At T1, the mean ANB was 5.1 degrees (SD: 1.6), the mean SN-PP 5.6 (SD: 3.0) and the mean MP-PP 28.7 degrees (SD: 4.0). The median follow-up time was 8.6 years with an interquartile range of 2.7. A statistically significant, but of small magnitude increase in the SNA angle was noted at T3 compared to T2 after adjusting for the pre-treatment SNA value (mean difference (MD): 0.75; 95% CI: 0.34, 1.15; P<0.001). The inclination of the palatal plane appeared stable in the post-treatment period, while the MP-PP angle showed scarce evidence of decrease during the post-treatment period after adjusting for sex, pre-treatment SNA and SN-PP angles (MD: -2.29; 95% CI: -2.85, -1.74; P<0.001). The sagittal position of the maxilla and the inclination of the palatal plane appeared to be stable after treatment with high-pull headgear and fixed appliances in the long-term. Continuous mandibular growth, both sagittaly and vertically, contributed to the stability of class II correction.

Craniofacial and upper airway morphological characteristics associated with the presence and severity of obstructive sleep apnea in Chinese children.

To identify craniofacial and upper airway morphological characteristics associated with the presence and severity of obstructive sleep apnea (OSA) in children. This study consisted of 82 OSA children and 77 controls (age 5-10 years). All subjects underwent cephalograms and were divided into a 5-7 age group and an 8-10 age group. Cephalometric variables were compared between OSA children and controls, and hierarchical regression analysis was performed to examine the relationship between cephalometric variables and OSA severity [expressed by the obstructive apnea-hypopnea index (OAHI)] in different age groups. Increased A/N ratio, narrowed posterior airway space, decreased SNA and SNB angles, and shortened ramus height were observed among OSA children in different age groups. In the 5-7 age group, the A/N ratio and a lower gonial angle explained 40.0% and 14.7% of the variance in the OAHI, respectively. In the 8-10 age group, the BMI z-score and A/N ratio explained 25.2% and 6.6% of the variance in the OAHI, followed by a lower gonial angle and the hyoid-retrognathion distance (19.1% in total). Adenoid hypertrophy was a major factor associated with OSA in preschool children, whereas obesity replaced adenoid hypertrophy as the main contributor to OSA in late childhood. Several craniofacial skeletal variables such as the SNB angle, ramus height, lower gonial angle, and hyoid position are also associated with the presence and/or severity of OSA, which could be used to help recognize children at a higher risk for OSA.

Effects of skeletal anchorage on mandibular rotation with fixed functional appliance therapy in class II malocclusion patients – A systematic review and meta-analysis

Objectives: The study aimed to systematically investigate the effect of skeletal anchorage on mandibular rotation during FFA therapy during Class II correction in adolescents. Material and Methods: The review protocol was registered under the PROSPERO database (CRD42021256690). Electronic searches of databases and screening were performed up to May 2022. Only randomized clinical trials (RCT) and non-randomized controlled trials (non-RCT) were included in the study. Revised Cochrane risk-of-bias tool for RCTs (RoB 2) and risk of bias in non-randomized studies-of interventions tool for non-RCT were used for studies. Meta-analysis was performed and a forest plot was obtained. The primary outcome was mandibular rotation. Other outcomes assessed were angles SNA, SNB, ANB, mandibular incisor proclination, and failure rates of mini-screws and mini plates. Results: Twelve studies (eight RCTs and four non-RCTs) were included fulfilling inclusion criteria. Evidence showed a low-to-moderate risk of bias for different domains. Meta-analysis for mandibular rotation revealed a greater increase in mandibular plane angle in patients who received FFA with skeletal anchorage as compared to patients who did not receive skeletal anchorage. Conclusion: With or without skeletal anchorage, mandibular rotational changes during FFA therapy are similar. FFA when combined with skeletal anchorage causes more skeletal changes in sagittal parameters than conventional FFA used alone. FFA with skeletal anchorage reduces lower incisor proclination.

Orofacial anatomical and occlusal changes in patients with sickle cell disease in Kuwait

ObjectiveSickle cell disease (SCD) is the most common hemoglobinopathy where morphologic changes to red blood cells affect the development of hard and soft tissues. The purpose of this study is to identify the craniofacial characteristics and maxillomandibular relationship in SCD patients and compare with unaffected subjects, through cephalometric radiographic assessment. Materials and MethodsThe study included 44 Kuwaiti SCD patients (20 female, 24 male) as well as 44 age and gender matched controls. Digital lateral cephalometric, radiographs were recorded. SNA and ANB angles were measured and compared. ResultsThe mean SNA angle was found to be higher among the SCD cases (83.00 ± 3.22) than in controls (81.78 ± 4.58), but the difference was not statistically significant, (p = 0.146). The mean ANB angle in SCD cases (5.27 ± 2.36) was significantly higher, than that in controls (3.97 ± 2.23). The difference in means was statistically significant, (p = 0.01). Almost 50% of the SCD patients had class II malocclusion and 61.5% of the patients had prognathic maxilla. ConclusionsPatients with SCD in Kuwait exhibited characteristics of skeletal class II pattern malocclusion. They also showed evidence of compensatory maxillary expansion.

Three-dimensional evaluation of the maxillary sinus in patients with different skeletal classes and cranio-maxillary relationships assessed with cone beam computed tomography

The objective was to evaluate the relationship between the dimensions of the maxillary sinuses (MSs) and various cephalometric parameters. MS volume (MSV), MS surface (MSS), linear maximum depth (LMD), linear maximum width (LMW), and linear maximum height (LMH) were calculated on CBCT scans of 99 adults. Two sets of two-way (ANOVA) assessed the influence respectively of ANB and SNA angles and of the gender on MS dimensions. Pearson’s correlation was calculated between MS dimensions and different cephalometric variables. Reliability and accuracy of the proposed method was tested with intra-operator and inter-operator intraclass correlation coefficient (ICC). Two-way ANOVA showed no statistically significant difference in MSV, MSS and LMH between ANB groups, whilst males were associated with bigger sinuses. LMW showed statistically significant difference in both ANB and gender groups. LMD showed no statistically significant difference. The second Two-way ANOVA showed significantly larger MSV, MSS and LMD in patients with increased or reduced SNA angle but not between genders. LMW and LMH also showed a significant difference between genders. All linear measurements showed a significant interaction of the two factors. The intra-observer and inter-observer ICC scored high for all the tested measurements. MSV and MSS showed a positive correlation with S-N, PNS-A, S-Go, N-Me, N-Ans and the distance between Mx points. LMW had a negative correlation with Ba-S-N angle and N-Me, LMH with Ba-S-N angle, S-Go and Mx r-Mx l and LMD with N-Me and N-ANS. LMW had a positive correlation with Mx r-Mx l, LMH with S-N, S-N^Ans-Pns, N-Me, N-Ans and LMD with S-N, Ba-S-N, PNS-A, S-Go and distance between Mx points. In conclusion, MSV and MSS did not differ between the three skeletal classes, males showed significantly larger MS than in females. Concerning the influence of the cranio-maxillary relationship (SNA) and gender on MS dimension, subjects with a retrusion (SNA < 80°) or protusion (SNA > 84°) of the maxillary alveolar bone had larger MSV, MSS, LMW, LMH and LMD than subjects with a normal cranio-maxillary relationship (SNA 82 ± 2°). A statistically significant high positive correlation was observed between S-N, Pns-A, S-Go, Mx-R/Mx-r and MS dimension. Further studies that evaluate similar outcomes in different races may be able to enrich our knowledge on this topic.

Lateral cephalometric characteristics in individuals with Down Syndrome compared to non-syndromic controls: A meta-analysis

ObjectivesThe aim of the present meta-analysis was to provide a complete synthesis of all studies involving lateral cephalometric measurements in populations with Down Syndrome (DS). MethodsA literature search was carried out using six electronic databases to identify studies comparing cephalometric characteristics between populations with DS and control (healthy) populations. Studies were selected according to the research objectives, and predefined inclusion and exclusion criteria. Only the cephalometric measurements included in three or more studies selected were analyzed. The random-effects meta-analysis model was used for data analysis, and all analyses were carried out using RevMan5 software. ResultsFrom an initial 871 articles identified through the literature search, ten cross-sectional studies were finally selected based on the inclusion and exclusion criteria. Ten cephalometric measurements underwent meta-analysis, five linear and five angular measurements. Concerning the five linear measurements, namely S-N, ANS-PNS, Go-Gn, Ar-Go, and N-ANS, all were significantly smaller in the DS group with the exception of Go-Gn. Of the five angular measurements, only three were statistically different between the DS and control groups. SNB and ANB angles were smaller in individuals with DS, whereas the basilar angle was larger. Subgroup analysis was also carried out based on age, and it was found that the gonial angle was significantly smaller before puberty, in individuals with DS. No differences between groups were found for the SNA angle. ConclusionThere are significant cephalometric differences between individuals with and without DS. Individuals with DS have a shorter anterior cranial base, maxillary length, upper anterior facial height and mandibular height. The ANB and SNB angles were also smaller in those with DS, but the SNA angle showed no differences. These findings may indicate that the Class III malocclusion commonly found in individuals with DS does not seem to be due to mandibular prognathism. Clinical relevanceLateral cephalometric measurements in individuals with DS show significant differences from individuals without DS. Practitioners need to be aware of this and monitor growth from an early age in these children.

Impact of Minor Suture Fusion on Midface Hypoplasia in Syndromic Craniosynostosis

Purpose: Early onset of minor suture fusion in syndromic craniosynostosis is associated with midface dysplasia and is a common indication for craniofacial surgery. However, the potential effects of fusion severity on craniofacial growth patterns are not well understood. This study seeks to describe the impact of minor suture fusion severity on midface morphology in Crouzon syndrome. Methods: Pre-operative computed tomography images (CT) of 63 patients with Crouzon syndrome and 63 normocepahlic controls were included. Degree of suture fusion was assessed for the frontosphenoidal, sphenethmoidal, sphenosquamosal, sphenopetrosal, spheno-occipital synchondrosis, frontoethmoidal, and zygomaticosphenoidal sutures. Each suture was graded on a 5-point scale. The sella (S), nasion (N), A point (A), basion (BA), and anterior nasal spine (ANS) landmarks were used to calculate the SNA angle, BA-ANS length of the lower midface, and N-S length of the upper midface. Multiple linear regressions were used to analyze data. Results: The mean age was 43 months and 44% were female. The control group was significantly older ( P &lt; .01) than the patients with Crouzon syndrome. Advanced fusion of the spheno-occipital synchondrosis in Crouzon syndrome correlates with regression of the BA-ANS length by 0.563 mm per incremental increase in suture fusion ( P &lt; .01). Additionally, the lower midface (BA-ANS) was restricted to a greater degree than the upper midface (N-S) with progressive suture fusion in all patient types with ratios of these rates ranging between 0.602 and 0.89 for the 7 sutures analyzed. Suture fusion severity did not impact the SNA angle in any of the analyses performed. Conclusion: The severity of sheno-occipital synchondrosis fusion in Crouzon syndrome contributes to midface hypoplasia. Similarly, all anterior skull base sutures limited lower midface growth to a greater degree than the upper midface.