Lateral Cephalometric Measurements Research Articles

Accuracy and clinical validity of automated cephalometric analysis using convolutional neural networks.

This study aimed to assess the error range of cephalometric measurements based on the landmarks detected using cascaded CNNs and determine how horizontal and vertical positional errors of individual landmarks affect lateral cephalometric measurements. In total, 120 lateral cephalograms were obtained consecutively from patients (mean age, 32.5 ± 11.6) who visited the Asan Medical Center, Seoul, Korea, for orthodontic treatment between 2019 and 2021. An automated lateral cephalometric analysis model previously developed from a nationwide multi-centre database was used to digitize the lateral cephalograms. The horizontal and vertical landmark position error attributable to the AI model was defined as the distance between the landmark identified by the human and that identified by the AI model on the x- and y-axes. The differences between the cephalometric measurements based on the landmarks identified by the AI model vs those identified by the human examiner were assessed. The association between the lateral cephalometric measurements and the positioning errors in the landmarks comprising the cephalometric measurement was assessed. The mean difference in the angular and linear measurements based on AI vs human landmark localization was .99 ± 1.05°, and .80 ± .82 mm, respectively. Significant differences between the measurements derived from AI-based and human localization were observed for all cephalometric variables except SNA, pog-Nperp, facial angle, SN-GoGn, FMA, Bjork sum, U1-SN, U1-FH, IMPA, L1-NB (angular) and interincisal angle. The errors in landmark positions, especially those that define reference planes, may significantly affect cephalometric measurements. The possibility of errors generated by automated lateral cephalometric analysis systems should be considered when using such systems for orthodontic diagnoses.

Hard tissue characteristics of patients with bimaxillary protrusion

Bimaxillary protrusion (BP) is a common developmental condition amongst the South African Black population characterized by proclined incisors with resultant procumbency of the lips. The aim of this study was to perform a cephalometric radiographic analysis of the pre-treatment dental and skeletal structures in a sample of Black South Africans in order to identify the characteristic features of BP in this race group and compare them to norms. Records of 67 South African Black patients divided into 28 males and 39 females with a mean age of 17.8 years, clinically diagnosed with BP were included in the study. Cephalometric parameters were hand traced on lateral cephalometric radiographs and measurements recorded for evaluation and comparison to norm values used for this population group to determine the features that both males and females present with. Characteristic pre-treatment dental features of the sample included maxillary incisors that were proclined and protruded with resultant decreased interincisal angle, mandibular incisors which were favourably positioned. Skeletal features included retrognathic jaws (maxilla to a greater degree) resulting in a mild to moderate Class III skeletal pattern but with females exhibiting a smaller ANB angle indicating a greater tendency for a Class III skeletal pattern. The skeletal growth pattern was vertically directed with an average anterior facial height ratio. The findings indicate that most BP patients in this South African Black population presented with dentoalveolar protrusion, retrognathic jaws and a mild to moderate skeletal Class III pattern

Comparison of Facial Growth Between Two Nasoalveolar Molding Techniques in Unilateral Complete Cleft Lip Patients: A Randomized, Prospective, Single-blind Trial.

Nasoalveolar molding (NAM) has become standard treatment in our Craniofacial Center. Two types of pre-surgical NAM, Grayson technique and Figueroa technique, co-exist. We previously found no differences in number of clinic visits, cost and 6 months post-operative outcome between the two techniques. Since Figueroa's method involves passive, whilst Grayson's method involves active, alveolar molding, we extended the previous study to evaluate facial growth between these two groups. This randomized, prospective, single-blind study, conducted between May 2010 and March 2013, recruited 30 patients with unilateral complete cleft lip and palate patients and randomized them for Grayson or Figueroa pre-surgical NAM. Their standard lateral cephalometric measurements at 5 years were used to determine facial growth. Twenty-nine patients completed 5 years of follow-up. There were no statistical differences in facial cephalometric measurements between the two groups. Pre-surgical NAM using either passive or active NAM technique produced similar facial growth patterns after unilateral cleft lip and palate repair.

Preciseness of artificial intelligence for lateral cephalometric measurements.

The aim of the study was to assess the accuracy and efficiency of anew artificial intelligence (AI) method in performing lateral cephalometric radiographic measurements. A total of 200lateral cephalometric radiographs were assessed for quality and included. Three methods were used to perform the cephalometric measurements: (1) the AI method using WebCeph software (AssembleCircle Corp., Gyeonggi-do, Republic of Korea), (2)the modified AI method using WebCeph software after manual modification of the landmarks' position, and (3)using OnyxCeph software (Image Instruments GmbH, Chemnitz, Germany) by manual landmark identification and digital measurements generation. The results of the measurements produced by the three methods were compared, in addition to comparing the time required for the measurements' generation required for each method. Statistically significant differences were detected between the measurements resulting from the three used methods. Fewer differences were detected between the modified AI method and the OnyxCeph method. The AI method produced the measurements the fastest followed by the modified AI method and then the OnyxCeph method. Considering the used AI software, AI followed by manual tuning of the landmarks' position might be an accurate method in lateral cephalometric analysis. AI alone is still not fully reliable at locating the different landmarks on the lateral cephalometric radiographs.

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.

Cephalometric determinants of facial attractiveness: A quadratic correlation study

This research aimed to determine the nonlinear correlation between lateral cephalometric measurements and facial attractiveness, evaluated in the frontal and profile views. A quadratic correlation was studied, in which the vertex of the function indicates the cephalometric value corresponding to the maximum attractiveness. Frontal and profile facial attractiveness of 60 patients with Class I (n= 20), Class II (n= 20), or Class III malocclusion (n= 20) aged 18-35 years without previous orthodontic treatment was evaluated by 14 laypersons (7 men and 7 women) with a visual analog scale. Soft- and hard-tissue measurements were collected on lateral cephalometric radiographs. Pearson and nonlinear quadratic correlations between the attractiveness of the face and cephalometric measurements were calculated. Maximum attractiveness values (MxAt) were determined for the significant cephalometric variables. Significant quadratic correlations were found between frontal facial attractiveness and the following variables: Ls-SnPog' (r= 0.45; MxAt= 3.1 mm), Li-SnPog' (r= 0.41; MxAt= 3.8 mm), the ANB angle (r= 0.42; MxAt= 0.2°) and MPA (r= 0.51; MxAt= 31.9°). Profile attractiveness correlated nonlinearly with Ls-SnPog' (r= 0.42; MxAt= 3.2 mm), Li-SnPog' (r= 0.41; MxAt= 3.9 mm) and MPA (r= 0.46; MxAt= 32.4°). Significant quadratic correlations were found between facial attractiveness and cephalometric measurements, which were stronger than linear correlations. The maximum attractiveness points indicated a tendency for laypeople to consider a more protrusive lower lip and an ANB angle lower than the norm as the most attractive.

Development of a new category system for the profile morphology of temporomandibular disorders patients based on cephalograms using cluster analysis.

This study aims to develop a new category scheme for the profile morphology of temporomandibular disorders (TMDs) based on lateral cephalometric morphology. Five hundred and one adult patients (91 males and 410 females) with TMD were enrolled in this study. Cluster tendency analysis, principal component analysis and cluster analysis were performed using 36 lateral cephalometric measurements. Classification and regression tree (CART) algorithm was used to construct a binary decision tree based on the clustering results. Twelve principal components were discovered in the TMD patients and were responsible for 91.2% of the variability. Cluster tendency of cephalometric data from TMD patients were confirmed and three subgroups were revealed by cluster analysis: (a) cluster 1: skeletal class I malocclusion; (b) cluster 2: skeletal class I malocclusion with increased facial height; (c) cluster 3: skeletal class II malocclusion with clockwise rotation of the mandible. Besides, CART model was built and the eight key morphological indicators from the decision tree model were convenient for clinical application, with the prediction accuracy up to 85.4%. Our study proposed a novel category system for the profile morphology of TMDs with three subgroups according to the cephalometric morphology, which may supplement the morphological understanding of TMD and benefit the management of the categorical treatment of TMD.

Association of Craniofacial Patterns with the Curve of Spee and the Time Required for Orthodontic Levelling.

The curve of Spee (CoS) is an important parameter for an individualized treatment plan. The available information regarding a potential association of the depth of the curve of Spee with various skeletal craniofacial characteristics is conflicting and it is also unknown whether certain craniofacial parameters affect the duration of the levelling phase of orthodontic treatment. A prospective sample of 32 patients with mild to moderate crowding that underwent orthodontic treatment with full fixed appliances was used to study these topics. The craniofacial characteristics were captured on pre-treatment lateral cephalometric radiographs and measurements of the CoS were performed on the initial 3D digital dental models using the Viewbox 4 software. Non-parametric statistics and Spearman’s correlations were applied. Weak negative correlations were detected between the CoS depth and the SNA and SNB angles. There was no other association between the CoS and craniofacial parameters, including various anteroposterior measurements. Furthermore, there was no significant association of any craniofacial parameter with the duration of the levelling. Contrary to certain clinical beliefs, it can be argued that the craniofacial characteristics are not associated with the CoS and the time required for its levelling in subjects with moderate pre-treatment CoS depth.

Does the floor of the maxillary sinus affect tooth movement for premolar extraction space closure?

The study investigated orthodontic tooth movement by comparing various horizontal and angular measures of the teeth having different sinus-root relationship (SRR) of patients undergoing first premolar extraction treatment protocols. This retrospective cross-sectional study included 45 Taiwanese adult patients, classified as the control group (n = 15) and the sinus group (n = 30) according to SRR. The control group had type I SRR (sinus floor above the level connecting the buccal and palatal root apices), whereas the sinus group included patients with type V SRR (the buccal and palatal root displayed apical protrusion into the sinus floor). Morphology was identified using pretreatment orthopantomograms. Lateral cephalometric measurements were conducted before treatment (T1) and at debonding (T2). Post debonding, there were no statistically significant difference in the two groups. However, the incisors in the control group became marginally more upright than those of the sinus group, and the molars demonstrated tipping movement with minimal anchorage loss in the sinus group than in the control group. The total treatment time was not significantly different between the 2 groups. The study revealed that the sinus-root relationship does not affect the orthodontic tooth movement. However, a more extensive 3-D study with larger sample size is strongly recommended before coming to any conclusion. The lining of the floor of the maxillary sinus does not affect the orthodontic tooth movement.

A comparative assessment of the dentoskeletal effects of clear aligners vs miniplate-supported posterior intrusion with fixed appliances in adult patients with anterior open bite. A multicenter, retrospective cohort study

This study aimed to retrospectively evaluate the dentoskeletal effects of clear aligners (Invisalign) vs miniplate-supported posterior intrusion (MSPI) and identify factors associated with posttreatment overbite in adults with anterior open bite. Twenty-nine patients treated with Invisalign and 24 with MSPI combined with full-fixed orthodontic appliances were included from 5 orthodontic practices. Pretreatment and posttreatment lateral cephalometric measurements were included as outcomes. Comparisons across groups and identification offinaloverbite predictors were assessed with regression modeling and machine learning techniques. MSPIinduced significantly greater maxillary molar intrusion (1.5 mm; 95% confidence interval [CI], 0.83-2.17; P<0.001), with subsequent reduction of anterior face height (ANS-Me) (-2.77 mm; 95% CI, -3.64 to -1.91;P<0.001), Mp-SN° (-1.95°; 95% CI, -2.77 to -1.12; P<0.001), and ANB° (-1.69°; 95% CI, -2.44 to -0.94; P<0.001) compared with Invisalign. MSPI resulted in a significantly larger increase in SNB° (0.94°; 95% CI, 0.23-1.65; P= 0.01) and point-Pog projection (2.45 mm; 95% CI, 1.12-3.77; P= 0.001). Compared with MSPI, Invisalign had a significantly greater increase in the distance of maxillary (1.05 mm; 95% CI, 0.38-1.72; P= 0.003) and mandibular (0.9 mm; 95% CI, 0.19-1.60; P= 0.01) incisal edges relative to their apical bases, with borderline greater lingual tipping of only the maxillary incisors (2.82°; 95% CI, -0.44 to 6.09; P=0.09). Appliance type and initial overbite were significant final overbite predictors across all models. However, this difference was only evident in male patients (males [1.65; 95% CI, 0.99-2.32; P<0.001]; female [-0.04; 95% CI, -0.52 to 0.44; P= 0.87]). Both appliances effectively improve overbite. MSPI applied the correction via molar intrusion and counterclockwise mandibular autorotation, whereas Invisalign via maxillary and mandibular incisor extrusion.

Skeletal, Dental, and Soft Tissue Changes after Applying Active Skeletonized Sutural Distractor (ASSD) for Class III Malocclusion Patients

Background: Nonsurgical treatment of Class III malocclusion may reduce the chances for orthognathic surgery in the future. This study aimed to determine the post-treatment skeletal, dental and soft tissue changes in the anteroposterior plane applying active skeletonized sutural distractor (ASSD) in late adolescent Class III malocclusion patients. Materials and Methods: After screening 13,500 students from 18 secondary schools, a sample of 26 subjects was recruited for this study, with a mean age of 15(±1.4) years after considering the inclusion and exclusion criteria. ASSD appliances were inserted into patients, and lateral cephalometric x-rays were taken for pre- and post-treatment analysis. Dental casts of the patients were also taken and scanned using a 3D laser scanner for comparisons. Results: The intraclass correlation coefficients (ICC) for inter-examiner were 0.87 to 0.99 and 0.96 to 0.99 for lateral cephalometric and dental cast measurements, respectively. The difference in pre- and post-treatment of cephalometric measurements of the mandible showed statistically significant changes for mandibular plane angle (p &lt; 0.001) and SNB angle (p = 0.029). The dental cast measurements showed statistically significant changes of inter-molars width (p &lt; 0.001) as well as palatal (p = 0.002). Conclusions: The results showed statistically significant improvement in skeletal, dental, and soft tissue changes after treatment applying ASSD for Class III malocclusion patients.

Potential impact of pediatric obstructive sleep apnea on mandibular cortical width dimensions.

To analyze differences in mandibular cortical width (MCW) among children diagnosed with obstructive sleep apnea (OSA) or at high- or low-risk for OSA. A total of 161 children were assessed: 60 children with polysomnographically diagnosed OSA, 56 children presenting symptoms suggestive of high-risk for OSA, and 45 children at low risk for OSA. Children at high- and low-risk for OSA were evaluated through the Pediatric Sleep Questionnaire. MCW was calculated using ImageJ software from panoramic radiograph images available from all participants. Differences between MCW measurements in the 3 groups were evaluated using analysis of covariance and Bonferroni post-hoc tests, with age as a covariate. The association between MCW and specific cephalometric variables was assessed through regression analysis. The participants' mean age was 9.6 ± 3.1 years (59% male and 41% female). The mean body mass index z-score was 0.62 ± 1.3. The polysomnographically diagnosed OSA group presented smaller MCW than the group at low-risk for OSA (mean difference = -0.385 mm, P = .001), but no difference with the group at high-risk for OSA (polysomnographically diagnosed OSA vs high-risk OSA: P = .085). In addition, the MCW in the group at high-risk for the OSA was significantly smaller than the group at low-risk for the OSA (mean difference = -0.301 mm, P = .014). The cephalometric variables (Sella-Nasion-A point angle (SNA) and Frankfort - Mandibular Plane angle (FMA)) explained only 8% of the variance in MCW. Reductions in MCW appear to be present among children with OSA or those at high-risk for OSA, suggesting potential interactions between mandibular bone development and/or homeostasis and pediatric OSA. Fernandes Fagundes NC, d'Apuzzo F, Perillo L, et al. Potential impact of pediatric obstructive sleep apnea on mandibular cortical width dimensions. J Clin Sleep Med. 2021;17(8):1627-1634.

LE FORT I OSTEOTOMİSİNDE İKİ PLAK İLE MAKSİLLER FİKSASYON YÖNTEMİ :TEKNİK RAPOR VE VAKA SUNUMU

Restoring facial esthetics and occlusion while maintaining long term stability are the goals of orthognathic surgery. Le Fort I osteotomy is frequently used for the correction of dentofacial deformities and is accepted as a relatively stable procedure. Many factors affecting the stability of the mobilized maxilla have been reported. Among these, the use of a stable internal fixation method is of primary importance to postoperative stability. Most oral and maxillofacial surgeons prefer bilaterally applying titanium miniplates in both the anterior apertura piriformis region and the posterior zygomaticomaxillary buttress region to achieve the rigid fixation of the maxillary segment following Le Fort I osteotomy. In the literature, there is currently a lack of agreement on the number of plates required to adequately secure the mobilized maxilla to prevent postoperative relapse. Reducing the number of miniplates allows surgeons to reduce any potential complications, operation time, and costs. In this case report, a patient with maxillary retrognathia and mandibular prognathia, manifesting dental Class III characteristics who underwent one piece Le Fort I osteotomy at Baskent University Faculty of Dentistry, Department of Oral and Maxillofacial Surgery was presented. Under general anesthesia one piece Le Fort I osteotomy was performed. Following down fracture, mobilization of the maxillary segment was completed and 10 mm horizontal advancement movement was achieved. Surgical rigid fixation was performed under intermaxillary fixation with surgical splints. Maxillary fixation was completed with two pre-bent titanium Le Fort I plate placed bilaterally at the piriform apertura with no zygomaticomaxillary buttress fixation. Prior to extubation, intermaxillary fixation and surgical splints were released. Intermaxillary elastics were used six to eight weeks following surgery in addition to a soft, no-chew diet. The patient received both preoperative and postoperative orthodontic treatment. Digital lateral cephalometric radiographs, which were taken one week before orthognatic surgery (T1), one week postoperatively (T2), and nine months postoperatively (T3), were used to analyze skeletal movement and stability of the maxilla. Lateral cephalometric measurements were performed digitally using a computer-assisted software program. Linear and angular measurements of sagittal and vertical maxillary positions was calculated. A horizontal reference plane (HR) +7° to the SN plane at the S point and a vertical reference plane (VR) 90° to the horizontal plane at the Sella point were used in the analyses. After completion of growth and development, the SN plane remains in the same position, giving us the opportunity to measure skeletal movement with these horizontal and vertical reference planes. The difference in the A point-HR distances between the pre and postoperative radiographs indicates the horizontal movement of the maxilla, whereas the difference in the A point-VR distances indicates the vertical movement of the maxilla. The major criteria for maxillary skeletal relapse was the change in the distance from the A point to the horizontal and vertical reference planes. Significant immediate postsurgical changes were found in early postoperative lateral cephalometric radiography (T2). In 9 month follow-up lateral cephalometric measurements (T3) all landmarks in the horizontal and vertical plane showed skeletal stability. The relapse amount in maxillary movement was less than 1 mm in both horizontal and vertical planes. According to the postoperative lateral cephalometric measurements, the two plate anterior fixation method in the one piece Le Fort I ostetomy showed satisfactory results in terms of skeletal stability.

Evaluation of effects of a modified asymmetric rapid maxillary expansion appliance on the upper airway volume by cone beam computed tomography

Background/purposeThe rapid maxillary expansion is accepted as the gold standard for the treatment of unilateral posterior crossbite in growing children. This study used cone beam computed tomography (CBCT) to evaluate the effects of a modified asymmetric rapid maxillary expansion (ARME) appliance on the upper airway volumes. Materials and methodsA modified ARME appliance was used on 12 adolescent male patients (mean age: 13.92 ± 0.82 years) with a class I skeletal relationship and posterior unilateral crossbite. Lateral cephalometric measurements and upper airway volume were evaluated using CBCT images. The posterior airway volumes of the oropharyngeal and nasopharyngeal airways were measured. ResultsCephalometric measurements showed significant (P < 0.05) posterior rotation of the mandible. There was no significant movement of the maxilla according to the cranial base on the sagittal plane. Nasopharyngeal and oropharyngeal airway volumes increased significantly (P < 0.05). ConclusionThe results of this study demonstrate that treatment with the modified ARME has no significant effect on the maxilla but may increase the upper airway volume.

Comparison of the postoperative stability after repositioning of the maxilla with Le Fort I osteotomy using four- versus two-plate fixation

IntroductionLe Fort I osteotomy procedures requires miniplates fixation in both the aperture piriformis and zygomaticomaxillary buttress. PurposeThe purpose of this study was to compare the postoperative stability of the Le Fort I osteotomy using four-plate versus two-plate fixation. Material and methodsThis study involved 39 Class III patients who underwent one-piece Le Fort I osteotomy with bilateral sagittal split ramus osteotomy. In group I, four miniplates were placed at the apertura piriformis and the zygomaticomaxillary buttress, whereas, in group II, fixation was achieved with two miniplates bilaterally placed at the piriform apertura with no posterior fixation. Linear and angular measurements included maxillary sagittal and vertical positions. The primary outcome of this study was stability, as recorded by lateral cephalometric measurements of the preoperative, immediately postoperative and late postoperative periods. ResultsSignificant immediate postsurgical changes were found in both groups. In the late postoperative cephalometric measurements, all skeletal parameters showed significant stability in groups I and II. In terms of vertical and sagittal relapse, there was no significant difference between the four-plate and two-plate groups (p1=0.686 and p2=0.513, respectively). ConclusionA good postoperative stability can be obtained with a two-plate fixation after one-piece Le Fort I osteotomy.

Evaluation of border movement of the mandible before and after orthognathic surgery using a kinesiograph

PurposeThe purpose of this study was to examine the changes in the mandibular border movement between class II and class III jaw deformity patients before and after orthognathic surgery, by using the same device. Subjectsand Methods: Eighty one patients (28 in class II and 53 in class III) who underwent sagittal split ramus osteotomy (SSRO) with Le Fort I osteotomy using absorbable plate fixation and 27 controls with normal occlusion were enrolled. Mandibular border movement (observed using a kinesiograph) was recorded with a mandibular movement measure system (K7) before surgery, and at 6 months and 1 year after surgery. Time-course changes of 5 components of the mandibular border movement (MVO: Maximum vertical opening, CO to MAP: Maximum antero-posterior movement from centric occlusion, MLDL: maximum lateral deviation left, MLDR: maximum lateral deviation right, CO to MO: centric occlusion to maximum opening) were compared between classes II, III and controls statistically. The relationship between lateral cephalometric measurements and the components of mandibular border movement was also examined. ResultsThere was a significant difference in CO to MAP (P = 0.0025) and CO to MO (P < 0.0001) between class II and class III in the time-course change.In class III, mean and standard deviation of MVO were 44.5 ± 6.7 mm before surgery and 39.8 ± 6.8 mm after 1 year. Mean and standard deviation of CO to MAP were 25.2 ± 6.8 mm before surgery and 21.5 ± 7.9 mm after 1 year. Mean and standard deviation of CO to MO were 53.4 ± 9.0 mm before surgery and 47.3 ± 8.4 mm after 1 year.In class II, mean and standard deviation of MVO were 38.8 ± 5.8 mm before surgery and 36.2 ± 7.4 mm after 1 year. Mean and standard deviation of CO to MAP were 18.0 ± 6.3 mm before surgery and 17.8 ± 7.4 mm after 1 year. Mean and standard deviation of CO to MO were 43.1 ± 7.5 mm before surgery and 39.6 ± 10.5 mm after 1 year.In MVO, CO to MAP and CO to MO, the values after 1 year did not significantly reach the pre-operative values in class III (P = 0.0001, P = 0.0007 and P < 0.0001), although there was no significant difference between pre-operation and after 1 year in class II.In CO to MO, class II (mean and standard deviation 39.6 ± 10.5 mm) and class III (mean and standard deviation 47.3 ± 8.4 mm) still remained smaller values than control (mean and standard deviation 52.7 ± 9.2 mm) after 1 year (P < 0.0001 and P = 0.0095). ConclusionThis study suggests that bi-maxillary surgery can have more influence on the reduction in the range of mandibular border movement including vertical or antero-posterior motion than lateral deviation motion, in both groups. The difference in the time-course change in the mandibular border movement between the groups might depend more on the mandibular length than on the movement direction of the mandible by surgery such as advancement or setback.

Estimation and Determination of Stature and Gender of Adult Chhattisgarh Population using Digital Lateral Cephalograms

Context: Digital lateral cephalograms are crucial in ascertaining stature and gender which lead to a clue for establishing identity as they are cost-effective, are easily available, and have reliable accuracy. Aims: The present study has an objective to determine gender and stature among 1000 adult Chhattisgarh males and females in the age range of 21–50 years using 14 linear lateral cephalometric measurements. The study attempted to derive a prediction equation for stature using lateral cephalometric parameters. Settings and Design: An observational, cross-sectional study was planned for stature and gender estimation using digital lateral cephalogram with study duration from July 2017 to August 2018. Methods: A total of 500 male and 500 female adult subjects in the age range of 21–50 years were subjected to digital lateral cephalogram, and 14 linear measurements were recorded for all subjects. Stature was measured using a stadiometer. Statistical Analysis: Linear regression analysis and correlation of lateral cephalometric parameters with stature were used for stature determination. Discriminant function analysis for gender prediction was used for ascertaining gender from lateral cephalometric parameters. Results: Of total 14 linear measurements, nine measurements among males and five among females were found to be positively and significantly correlated with stature. Correct gender determination was done in 83.5% of subjects using discriminant function analysis from lateral cephalometric measurements. Conclusions: Digital lateral cephalometric analysis can be used with fair accuracy for stature and gender prediction among adult Chhattisgarh population.

Comparison of Two Retention Appliances with Respect to Clinical Effectiveness

The aim of this study was to compare the clinical effectiveness of Essix and Hawley retainers during the retention period. A total of 30 subjects whose fixed orthodontic treatment results were evaluated according to the American Board of Orthodontics Phase III Objective Grading system were included in this study. After the removal of orthodontic attachments, the study participants were equally divided into two retention protocols: upper-lower Essix and upper-lower Hawley. The subjects were instructed to wear their retainers full time for 6 months, except during meals, and during nights only for 6 months. The clinical effectiveness of the retainers was evaluated according to the overjet, overbite, maxillary, and mandibular intercanine widths, intermolar widths, arch lengths, irregularity indexes, and lateral cephalometric measurements. All dental model and lateral cephalometric measurements were performed by the same investigator during three periods: pre-treatment, post-treatment, and post-retention. The overjet, overbite, maxillary, and mandibular intercanine widths; intermolar widths; and arch lengths and lateral cephalometric measurements were not statistically significantly different between the groups and identified time periods. Although the maxillary and mandibular irregularity indexes increased from the post-treatment to post-retention periods, the difference was not statistically significant. Pre-treatment, post-treatment, and post-retention lateral cephalometric measurements were not statistically significantly different between and within the groups. According to the results of a repeated-measures analysis of variance with two factors, and although an increase was found in the maxillary and mandibular irregularity indexes, the clinical effectiveness of Essix and Hawley retainers was found to be similar during the retention period.

Lateral cephalometric measurements of Iranians with surgically repaired unilateral cleft lips and palates

Since results of surgical correction of unilateral cleft lip and palate (UCLP) are controversial, and there is no study in this regard among Iranians, this study was conducted to document lateral cephalometric measurements of such cases, with respect to age, gender, and cleft side. In this cross-sectional study, 45 lateral cephalographs of individuals with UCLP who had undergone surgery but not orthodontic treatment were traced and 30 skeletal, dental and soft-tissue cephalometric measurements were measured. Parameters were compared between patients with UCLP and cephalometric norms. They were also compared between males and females, two age groups (≤8 and>8 years), and sides of cleft using the Student's t-test. Only S-N-Pog and U1-SN values were significantly different between this sample and cephalometric norms. The variables were not significantly different between males and females. However, the values of ANB, Wits appraisal, Go-Gn, Go-Pog, U1-SN, interincisal angle, distance of upper lip to Ricketts E-line, and nasopharyngeal depth were significantly different between patients≤8 and>8 years (P<0.05). The S-N-Pog angle, Wits appraisal, Go-Gn, Go-Pog, U1-SN, interincisal angle and hypopharyngeal depth were significantly different between patients with right- and left-side clefts (P<0.05). Measurements of patients with repaired UCLP were similar to cephalometric norms except for two parameters.

Role of dental radiologists in diagnosis of patients with high risk of obstructive sleep apnea using lateral cephalogram: A case–control study

Intoduction: OSA consists of repetitive short episodes of UA collapse with complete (apneas) or partial (hypopneas) obstruction of airway during sleep, associated with snoring and transient arousal, causing sleep fragmentation and insufficient and nonrestorative sleep. Aim: To recognize patients with high risk of obstructive sleep apnea using lateral cephalometric measurements in patients receiving routine dental treatment. Materials and Methods: The study was conducted on 120 patients, which were divided into two groups based on Berlin questionnaire which include 10 questions in 3 categories (snoring, day time drowsiness and hypertension/obesity) the study Group included 60 Patients and 60 normal patients. Digital Lateral Cephalometric analysis was done in all individuals to measure upper air way diameter (UAD), mandibular to hyoid distance (MHD) and to evaluate shape of soft palate (velar), by two observers at two different intervals. The data were statistically evaluated with student't' test and chi Square test using SPSS version 23.0.0. Results: The study comprised of 120 subjects who were divided into different age groups ranging from 18-65yrs. There were 61 males and 59 females when patients were divided according to gender and had no statistical significance. Based on Berlin questionnaire 51.7% were on high risk and 48.3% were on low risk. The UAD was reduced in study group than in control group and was statistically significant (P = 0.044). The MHD distance was increased in study group when compared with control group and was statistically highly significant (P