Lateral Cephalograms Research Articles

Vertical Dimension Control in Two Different Treatment Protocols: Invisalign First and Bite Block-A Retrospective Study.

The aim of the present study was to compare the vertical dimension changes, before and after treatment, in two groups of growing patients, one group treated with clear aligner therapy versus a group treated with Quad-helix and bite-block therapy. The studied sample was composed of n. 40 patients (20 females and 20 males with a mean age of 8.6 ± 1.8 years), enrolled from the Department of Orthodontics at Policlinico of Rome Tor Vergata. The original sample was randomly divided into two groups: Group IF (Invisalign First) and Group BB (Quad-helix and bite block). Pre- (T0) and post-treatment (T1 after 12 months) lateral cephalograms were collected from all the selected patients. Nine cephalometric parameters, both angular and linear, were measured and recorded for each cephalogram. No statistically significant changes were found between both the IF and BB groups at T0, while statistically significant changes were observed in both groups (BB and IF) between T0 and T1 (after 12 months of active therapy), p < 0.005. Both therapies were able to control the patient's vertical condition. To date, the use of conventional appliances seems to have slightly better efficacy in controlling the vertical dimension than aligner therapy.

Assessing position changes of impacted third molars in treatment of class II malocclusion with premolars extraction.

Third molars (M3) remaining impacted in Class II malocclusion characterised with sagittal mandibular deficiency is a high probability. The null hypothesis of this study is that mesioangular M3s changes position through the eruption way inClass II malocclusion treatmentrequiring moderate anchoragewith four first premolars extraction.The aim of this study is to reconsider the decision to surgically extract impacted third molars in four premolars extraction treatment of Class II malocclusion. The materials consisted of the pre-treatment and post-treatment lateral cephalograms and orthopantomographs of 30 individuals with skeletal and dental Class II malocclusion with a mean chronological age of 13.48 years, who were treated by the same clinician (H.G.) with four first premolar extractions via the straight wire technique at the Ankara University Faculty of Dentistry Department of Orthodontics, Ankara, Turkey. The sagittal position of the upper and lower incisors and molars, M3position and M3space were evaluated with the paired-t test; the relationship between the sagittal position of the upper and lower incisors and molars and the change in M3position were evaluated with correlation analysis. Results: The study found the retroclination and mesial movement of the upper incisors and molars, and an increase in the M3space by the fixed orthodontictreatment. An insignificant steepening of both the upper right M3position and the lower right M3position was found. A statistically significant increase in the lower right and left side M3spaces was found. Positive correlations between lower right M3angulation and the sagittal position of the lower incisors and first molars were found. Improvement in the mesioangulation of the M3s and an increase in the M3space were achieved in this study. Based on the findings, it is useful to review the decision for prophylactic surgical extraction of the M3s before orthodontic treatment in such cases, taking into account the risks of postoperative complications.

A cephalometric analysis of the antegonial notch in relation to the direction of mandibular growth.

Masticatory muscle forces influence craniofacial morphology development. The antegonial notch (Notch) is a bony concavity on the inferior border of the mandible. Considering the Notch is located anteriorly to the insertion of the masseter muscle and varies among individuals, we hypothesised that these muscles influence the formation of the Notch. Therefore, this study aimed to investigate the correlation between mandible morphology and Notch formation. Sixty Japanese patients who visited the Department of Orthodontics at our university hospital were retrospectively evaluated. Morphological and morphometric analyses of the Notch and related craniofacial parameters were conducted using lateral cephalograms taken at the patients' initial visits. Standard values for the Notch area and depth were determined, and the morphology of the Notch and mandible was analysed using Spearman's rank correlation coefficient (p < 0.05). The mean Notch area and depth was 78.71 ± 36.54 mm2 and 3.11 ± 1.09mm, respectively. The Notch area was significantly correlated with ramus inclination (p = 0.044, r = 0.261) and with the Y-axis (p = 0.039, r = 0.267). This study indicated that both the masticatory muscles and mandibular growth could contribute to the Notch formation.

Impact of Stabilization Splint Therapy on Orthodontic Diagnosis in Patients with Signs and Symptoms of Temporomandibular Disorder.

The relation between the orthopedic temporomandibular joint (TMJ) instability and temporomandibular disorder (TMD) most commonly remain unrecognized by orthodontists. In this study we aimed to evaluate the dentofacial characteristics and temporomandibular disorder symptomatology of patients with orthopedic instability before and after deprogramming with a stabilization splint. Sixty patients with the signs and symptoms of TMD were assessed using the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and underwent stabilization splint therapy to place the condyles in a more stable musculoskeletal position. The extent of condylar displacement was evaluated using the condylar position indicator (CPI). Sixteen angular and linear hard tissue landmarks were traced and compared from lateral cephalograms taken in the maximum intercuspation (MI) position before, and in the centric relation (CR) position after, the splint therapy. Following the splint therapy, the signs and symptoms of TMD were significantly reduced or completely eliminated in more than 90% of patients. Compared with the values registered before the splint therapy, a significant reduction in the mean values of condylar displacement was observed on both sides of the vertical (p < 0.001), horizontal (p < 0.05), and transverse (p < 0.001) planes of space after the splint therapy. A comparison of pre- and post-splint lateral cephalograms revealed that, following the splint therapy, the mandible moved more posteriorly and rotated in a more clockwise direction. In patients with orthopedic instability and the signs and symptoms of TMD, muscle deprogramming with a stabilization splint therapy is highly recommended to improve the health of the temporomandibular joint and masticatory structures and contribute to a more correct orthodontic diagnosis.

Evaluating anchorage and torque control in adolescent patients with Class II Division 1 malocclusion among 3 appliances

The objective of this study was to compare the differences in anchorage and torque control among the Tweed edgewise, Roth, and physiological anchorage Spee-wire systems (PASS) appliances (Zhejiang Xinya Technology Co, Ltd, Hangzhou, China). A sample of 90 adolescent patients with Angle Class II Division 1 malocclusion (30 Tweed edgewise appliances, 30 Roth appliances, and 30 PASS appliances) with maximum anchorage requirements in the maxilla were collected for this study. The pretreatment baseline levels of the 3 groups were compared initially, and then the differences between the 3 appliances in anchorage and torque control were analyzed after superimposing the pretreatment and posttreatment lateral cephalograms and maxillary 3-dimensional (3D) digital models, respectively. There was no statistical difference in the pretreatment baseline levels of 3 groups, including gender, age, sagittal skeletal types (ANB), vertical skeletal types (SN-GoGn), anchorage requirements, and occlusal plane inclination (SN-OP). After superimposing the pretreatment and posttreatment lateral cephalograms and 3D digital models, respectively, no statistical differences were observed between the measurement results obtained from lateral cephalograms and 3D digital models. Among the measurement variables assessed in this study, statistical differences were observed in the mesial displacement of maxillary first molars, the incisor retraction, and the torque variation of maxillary central incisors among the 3 groups. Specifically, the Tweed group exhibited lower mesial displacement of maxillary first molars compared with the PASS and Roth groups. Furthermore, the Tweed group exhibited the greatest amount of incisor retraction and torque variation of maxillary central incisors, followed by the Roth group and then the PASS group. The remaining measurement variables for the 3 groups showed no statistical differences, including vertical variation of maxillary first molars and central incisors, torque variation of maxillary first molars and canines, mesiodistal inclination variation of maxillary first molars and canines, width variation between maxillary first molars, and width variation between maxillary canines. Compared with contemporary preadjusted straight wire appliances, the Tweed edgewise appliance has superiority in molar anchorage control. In contrast, compared with the Roth appliances, the PASS appliances without any auxiliary anchorage devices could make full use of physiological anchorage to achieve adequate control of molar anchorage. Clinical orthodontists may need to pay extra attention to physiological anchorage. The difference in torque control varies depending on the respective characteristics of bracket designs.

Esthetic preferences of orthodontists, general dentists, and laypersons for Indian facial profiles: A cross-sectional study.

Background: Disparity in the esthetic perceptions between a patient and clinician could result in patient dissatisfaction with orthodontic treatment outcomes. The aim of this study was to compare the perceptions of a group of orthodontists, general dentists, and laypersons about the attractiveness of Indian facial profiles. Methods: In this study, a male and a female participants' photographs and lateral cephalograms were digitally manipulated by inserting them into Dolphin software; we considered four soft tissue parameters at a nasolabial angle, upper lip E-line, lower lip E-line, and pg-pg', so that 20 profiles were created for each model. A visual analog scale (VAS) along with a question about surgical correction opinion was given to 18 orthodontists, 18 general dentists, and 18 laypersons to score (1-5) from least to most attractive. Spearman's rank correlation was computed to assess correlation, as well as ANOVA, followed by post hoc Tukey analysis to compare the mean scores, and Chi-square test to determine the opinion about surgical treatment. Results: There was an overall weak and negative correlation between the three groups, indicating that orthodontists attributed lower pleasantness scores to almost all the altered female and male facial profiles. Additionally, statistically significantly lower mean scores were attributed by orthodontists to many females and few male facial profiles. More orthodontists identified the need for surgical correction for a few severely distorted profiles but there was a statistically non-significant difference among the groups for most of the profiles. Conclusions: It was concluded that participants in the three groups had diverse concepts of facial attractiveness in all the parameters considered. Compared to general dentists and laypersons, orthodontists were much more precise, firmer, and meticulous in identifying a favorable or good-looking profile.

Is occlusal contact re-established within 6 months after bonding of a fixed anterior bite plane in adolescents with a Class II division 2 incisor relationship? A randomised controlled trial.

To determine if re-establishment of occlusal contact was achieved within 6 months after insertion of a fixed anterior bite plane in individuals with Class II division 2 incisor relationship, and to evaluate the occlusal and vertical skeletal changes and acceptance of the intra-oral scanner and bite plane. Single-centre two-arm parallel group randomised controlled trial with 1:1 allocation to intervention and control groups. Dundee Dental Hospital and Research School, UK. A total of 38 participants aged 9-16 years (11 males, 27 females) with Class II division 2 incisor relationship and increased overbite (greater than one-third incisor overlap). Participants were randomised to intervention (n = 19) and control (n = 19) groups using block randomisation. The intervention group had a fixed anterior bite plane, and the occlusion and vertical facial dimensions were monitored with intra-oral scans, lateral cephalograms and photographs. The control group received no treatment and occlusal and vertical facial dimensions were monitored with scans and photographs. Questionnaires were completed by participants and parents/carers. An intention-to-treat analysis was planned. The overbite reduced in all participants in the intervention group (mean initial overbite: 5.07 mm, 95% confidence interval [CI] = 4.15-6.00; mean overbite after 6 months: 2.45 mm, 95% CI = 1.93-2.96). There was a mean incisor intrusion of 0.29 mm (95% CI = 0.17-0.42) and mean eruption of the first molars of 0.23 mm (95% CI = 0.09-0.37). There was no significant change in incisor inclination or vertical skeletal change. Feedback from participants and their parents/carers were generally positive. Fixed anterior bite planes effectively reduce an increased overbite in adolescents with a Class II division 2 incisor relationship, due to a combination of incisor intrusion and molar eruption with no change in incisor inclination or vertical skeletal change. Intra-oral scanning and fixed anterior bite planes are acceptable in adolescents.

Skeletal and dental features of class II malocclusion among Palestinian population: a retrospective cephalometric study

Aim. This study aims to assess the dentofacial characteristics for a sample of palestinian population with skeletal Class II malocclusion. Methods. A total of 170 lateral cephalograms for non-growing patients (age ranged between 19 and 32 years) with skeletal Class II malocclusion were retrieved. The lateral cephalograms were analyzed using virtual cephalometric analysis software - WeDoCeph® (Audax®, Ljubljana, Slovenia) to assess sagittal and vertical Skeletal parameters including SNA, SNB, ANB, SN/Mandibular Plane angle SN/Go-Gn, FMA and the Y axis angle were measured. Moreover, the upper and lower dental angular parameters (Maxillary incisor long axis with Sella - Nasion line (U1-SN), Maxillary incisor long axis with Nasion - point A angular (U1-A Point), Mandibular incisor long axis with mandibular plane (L1-MP), Mandibular incisor with nasion-point B (L1- NB) angular were also measured. The mean and standard deviation for each measurement were calculated using the Statistical Package for Social Sciences (Minitab) for Windows. Gender differences were analyzed using the independent t-test. Results. One-hundred and seventy lateral cephalometric radiographs were retrieved and analyzed. The Class II skeletal value (ANB value of 6.7 degrees) was mainly due to retrognathic mandible (SNB 75.5 degrees) rather than prognathic maxilla (SNA 82.2 degrees). In the vertical dimension, the Y axis angle, SN/Go-Gn angle, and FMA were generally increased. Regarding the dental parameters, the upper incisors were mostly retroclined, while the lower incisors were mostly proclined. There was a significant gender difference in two parameters (SN/Go-Gn and the L1-MP), where females showed more vertical growth and more lower incisors proclination. Conclusions. Skeletal class II malocclusion in the studied sample was characterized by retrognathic mandible, increased vertical growth, and compensated upper and lower incisors. Compared with male subjects, females significantly had more vertical growth and more lower incisor proclination.

Condylar Remodeling and Skeletal Changes Following Occlusal Splint and Manual Therapy: A Cone Beam Computed Tomography Study in Temporomandibular Disorders.

Background: Temporomandibular disorders (TMD) may be associated with degenerative disease of temporomandibular joint (TMJ), such as condyle erosion and subchondral cysts. Occlusal splint and cranio-mandibular manual therapy, or combined therapy, is recommended as a conservative treatment to alleviate pain-related signs and symptoms in TMD. This study aimed to assess osseous condylar changes and skeletal changes following occlusal splint and cranio-mandibular manual therapy in TMD using cone beam computed tomography (CBCT). Methods: A retrospective cohort study included 24 patients diagnosed with TMD. Combined therapy was performed until pain-related signs and symptoms disappeared. CBCT scans were performed before and after therapy. Osseous structure of condyles and their subsequent modifications were analyzed on CBCT images: flattening, erosion, and subchondral cyst. Sella-Nasion-A point (SNA), Sella-Nasion-B point (SNB), A point-Nasion-B point (ANB), Sella-Articulare-Gonion (Condylar angle), and anterior and posterior facial height (AFH, PFH) were measured on CBCT-generated lateral cephalograms. A paired t-test, Wilcoxon rank-sum test, McNemar test, and Stuart-Maxwell test were used for the statistical analyses. Results: The treatment period with combined therapy was 7.42 ± 3.27 months, and 21 out of 33 TMJ presenting degenerative disease (63.6%) had significant complete remodeling (p < 0.05). Following therapy, SNB significantly decreased from 75.61 ±3.47° to 74.82 ± 3.41° (p = 0.02), ANB significantly increased from 4.05° (3.35-4.9°) to 4.8° (3.3-6.12°) (p < 0.001), AFH significantly increased from 112.85 mm (109.28-118.72) to 115.3 mm (112.58-118.88) (p < 0.001), PFH/AFH significantly decreased from 64.17 (61.39-66.1) to 63 (59.68-64.51) (p = 0.012), and condylar angle significantly increased from 140.84 ± 8.18° to 144.42 ± 8.87° (p = 0.007). Conclusion: Combined therapy promoted significant condylar remodeling in TMJ degenerative disease, along with skeletal changes (mandibular retrusion and increase in facial height). Therapeutic strategies should consider condylar remodeling in TMD. Skeletal and dental parameters should be evaluated prior to occlusal splint therapy.

Evaluation of Incisor Position in a Sample of Orthodontic Patients.

To achieve a successful result, the orthodontist must use a systematic approach to plan the orthodontic treatment. Defining the correct position of the upper and lower incisors and evaluating their relationship with intermaxillary discrepancy and facial divergence have been recognized as the starting point for the diagnostic decision regarding extractions and anchorage requirements. The aim of our study was to analyze the relationship between intermaxillary discrepancy (ANPg^), mandibular inclination (SN^GoGn), lip incompetence, and the positioning of the upper and lower incisors (UIPs and LIPs) in a group of orthodontic patients. This retrospective study included 290 lateral cephalograms in 122 males (42.1%) and 168 females (57.9%) aged 8 to 53 years (median 14; interquartile range IQR 12-17). Data were analyzed by means of one-way Analysis of Variance (ANOVA) and linear regression analysis. This study showed a statistically significant increase in LIP values in patients with lip incompetence (p < 0.001). Moreover, the distribution of LIPs in groups with various SN^GoGn and ANPg^ angles was significantly different (p < 0.001). The regression analysis also showed a positive association between the LIP and SN^GoGn and between the LIP and ANPg^. The LIP presented a statistically significant difference in patients with and without lip incompetence, which varied significantly in subjects with different sagittal malocclusions and vertical face patterns.

Classification of cervical vertebral maturation stages with machine learning models: leveraging datasets with high inter- and intra-observer agreement

ObjectivesThis study aimed to assess the accuracy of machine learning (ML) models with feature selection technique in classifying cervical vertebral maturation stages (CVMS). Consensus-based datasets were used for models training and evaluation for their model generalization capabilities on unseen datasets.MethodsThree clinicians independently rated CVMS on 1380 lateral cephalograms, resulting in the creation of five datasets: two consensus-based datasets (Complete Agreement and Majority Voting), and three datasets based on a single rater’s evaluations. Additionally, landmarks annotation of the second to fourth cervical vertebrae and patients’ information underwent a feature selection process. These datasets were used to train various ML models and identify the top-performing model for each dataset. These models were subsequently tested on their generalization capabilities.ResultsFeatures that considered significant in the consensus-based datasets were consistent with a CVMS guideline. The Support Vector Machine model on the Complete Agreement dataset achieved the highest accuracy (77.4%), followed by the Multi-Layer Perceptron model on the Majority Voting dataset (69.6%). Models from individual ratings showed lower accuracies (60.4–67.9%). The consensus-based training models also exhibited lower coefficient of variation (CV), indicating superior generalization capability compared to models from single raters.ConclusionML models trained on consensus-based datasets for CVMS classification exhibited the highest accuracy, with significant features consistent with the original CVMS guidelines. These models also showed robust generalization capabilities, underscoring the importance of dataset quality.

Comparative Evaluation and Correlation of Hyoid Bone Position, Airway Dimension, and Psychological Status in Class II Vertical and Horizontal Malocclusion Cases With Temporomandibular Disorder Compared to Class I Non-Temporomandibular Disorder Cases.

Introduction Temporomandibular disorder (TMD) involves discomfort and impaired function in the masticatory muscles and temporomandibular joint (TMJ), with a multifaceted etiology that includes biomechanical, neuromuscular, psychological, and biological factors. This research aims to assess and correlate the hyoid bone position, airway dimensions, and psychological status in class II Hz (horizontal) and Vt (vertical) malocclusion cases with TMD in contrast to non-TMD class I cases. Methodology This research was carried out at the Orthodontics Department, Sharad Pawar Dental College and Hospital, Sawangi, with consent obtained from the ethical committee. A total of 63 adult patients with class I, class II horizontal, and class II vertical malocclusions were selected. TMD was diagnosed using the Helkimo index, and patients were categorized accordingly. Psychological status was evaluated using the Warwick-Edinburgh scale, while the placement of hyoid bone and airway dimensions were assessed using lateral cephalograms. Statistical analysis involved descriptive and inferential statistics using SPSS version 27.0, with a significance level ofp < 0.05. Results The research showed a noteworthy difference in the hyoid bone's location, airway dimensions, and psychological status among the three groups. Class II TMD patients (both vertical and horizontal) exhibited higher hyoid bone positions and larger Go-Hy-Me angles (angle formed by the gonion-hyoid line and the hyoid-menton line)compared to class I patients. In addition, class II vertical TMD patients showed the most reduced airway dimensions. Psychological assessments indicated higher stress, anxiety, and depression levels in class II TMD patients, particularly in the vertical group, compared to class I non-TMD patients. Conclusion This study highlights the intricate relationships between hyoid bone position, airway dimensions, and psychological status in TMD patients. TMD patients present with hyoid bones positioned closer to the cranium and mandible, larger Go-Hy-Me angles, and reduced airway dimensions. Psychological distress exacerbates TMD symptoms, negatively impacting overall well-being and quality of life. Orthodontists should consider these interrelated factors when devising treatment plans to improve patient outcomes. Future longitudinal studies with larger samples and advanced imaging techniques are recommended to further elucidate these interactions.

Comparison between twin block appliance and mandibular advancement on clear aligners in the improvement of airway dimension: incremental versus maximum bite advancement.

The aim of the present retrospective study was to compare the changes resulting from treatment using the MA and the TB with special regard to the oro-and naso-pharyngeal sagittal airway dimensions in subjects with dentoskeletal Class II malocclusions and positive history of Sleep Disorder Breathing (SDB) diagnosed through the Pediatric Sleep Questionnaire (PSQ). This retrospective study involved 2 groups of subjects: patients treated with Twin Block (TB group: n = 22, 10 males, 12 females; mean age 12.0 ± 1.3 years) and patients treated with Mandibular Advancement (MA group: n = 23, 11 males, 12 females; mean age 12.2 ± 1.1 years). Pretreatment (T1) and posttreatment (T2) lateral cephalograms were analyzed. All patients underwent the PSQ to diagnose SDB. In both treated groups there was an increase in the airways dimensions and an improvement in symptoms related SDB. The statistical comparison of the changes between T1 and T2 in the TB group showed a significant increment in upper airway size (PNS-AD2, +1.50 mm + -3.30; McNamara's upper pharynx dimension, +2.21 + -4.21) after active treatment. The MA group showed similar results during active treatment with a significant increase in both upper (PNS-AD2, +2.72 + -2.65; McNamara's upper pharynx dimension, +2.97 + -3.07) and lower (PNS-AD1, +2.17 mm + -3.54) airway size. Despite the different structure of these two devices and the different advancement protocols, both appliances were valuable as a suitable treatment option for Class II patients with respiratory disorders, inducing an increase of upper and lower airway size and a significant reduction in diurnal symptoms.

A Method for Studying the Size and Position of the Apical Bases of the Jaws Using Computed Tomography of the Jaws

The study of the apical bases has been relevant in orthodontics for many decades; its study was carried out both on jaw models and on lateral cephalograms. Dentistry today is impossible without three-dimensional studies, which allows you to study an object from any angle and visualize the smallest changes in the anatomical structures of the area under study. The use of cone beam computed tomography to study the apical bases of the jaws makes it possible to study the configuration, size, and position of both the bases themselves and the structures that form them. The parameters we proposed allow us to study the width, length and angle of inclination of the apical base on single CBCT sections. Clinical use of the proposed analysis will contribute to more complete and accurate orthodontic treatment planning.

EVALUATION OF THE RELATIONSHIP OF CURVE OF SPEE WITH DENTOSKELETAL MORPHOLOGY IN SAGITTAL MALOCCLUSIONS

Curve of Spee is defined as the line on a cylinder which is tangent to incisal edges of lower anteriors, occlusal surface of lower second molar and anterior border of condyle. The aim of the study is to determine whether there is a relationship between curve of Spee and craniofacial morphology in different sagittal malocclusions and to determine the influence of craniofacial morphological features in different sagittal malocclusions on curve of Spee. The research consists in the analysis of lateral cephalograms and study models of 90 patients, age 15-25 years which includes skeletal class I, class II and skeletal class III. Patients are divided into three groups: group A-flat curve of Spee i.e. &lt; 2mm, group B - normal curve of Spee i.e. 2-3 mm, and group C - deep curve of Spee i.e. &gt;3mm. In the literature, there is little data on research that has been done on this topic, on the other hand, in our daily work as orthodontists, we encounter the problem of leveling the deep bite.

Evaluating the efficiency of mandibular molar protraction using Herbst appliances versus temporary anchorage devices: a retrospective case-controlled study

BackgroundMandibular second premolar agenesis is a common problem in orthodontics and is often treated in conjunction with maxillary counterbalancing extractions. However, in cases without maxillary crowding or dental protrusion, space closure may pose challenges leading to compromised occlusal results or patient profile. Multiple techniques have been described to treat these patients; nevertheless, there is a paucity of data comparing effectiveness of space closure utilizing various anchorage techniques. The goal of this study is to assess the effectiveness of the Herbst device during mandibular molar protraction and compare it to the use of temporary anchorage device (TADs) in patients with mandibular second premolar agenesis.Materials and methodsThis retrospective study included 33 patients with mandibular premolar agenesis treated without maxillary extractions. Of these patients, 21 were treated with protraction Herbst devices and 12 with TADs. Changes in molar and incisor positions, skeletal base positions and occlusal plane angulations were assessed on pretreatment (T0) and post-treatment (T1) lateral cephalograms. Scans/photographs at T0 and T1 were used to evaluate canine relationship changes representing anchorage control. Space closure and breakage/failure rates were also compared. Data was analyzed with paired and unpaired t-tests at the significance level of 0.05.ResultsWithin the Herbst group, changes in mandibular central incisor uprighting and mandibular molar crown angulations were statistically significant. However, no significant differences were noted between the Herbst and TAD groups. Protraction rates as well as overall treatment times were comparable (0.77 mm/month vs. 0.55 mm/month and 3.02 years vs. 2.67 years, respectively). Canine relationships were maintained or improved toward a class I in 82.85% of the Herbst sample, compared to in 66.7% of the TAD sample. Emergency visits occurred in 80.1% of the Herbst group, with cementation failures or appliance breakages as the most common reasons.ConclusionThe Herbst device could be a viable modality in cases with missing mandibular premolars where maximum anterior anchorage is desired, or if patients/parents are resistant to TADs. Furthermore, they could be beneficial in skeletal class II patients with mandibular deficiency who also need molar protraction. However, the increased incidence of emergency visits must be considered when treatment is planned.

Evaluation of soft tissue profile changes around the nose and upper lip following maxillary anterior alveolar osteotomy with Wassmund and Wunderer technique in Japanese

PurposeThe extent to which maxillary anterior alveolar osteotomy alters the facial profile remains unclear. The present study retrospectively analyzed and evaluated changes in maxillary anterior fragments and soft tissue from the nose to upper lip from pre- to postoperatively in patients who underwent the Wassmund and Wunderer (WW) technique. MethodsThirty-seven Japanese patients with maxillary prognathism underwent orthognathic surgery with the WW technique were retrospectively included in the present study. Changes in both hard- and soft-tissue landmarks and correlations between both tissues were evaluated using lateral cephalograms taken immediately before and ≥6 months after orthognathic surgery. ResultsThe maxillary anterior segment showed predominantly posterior movement, with only slight upward movement. Posterior shift and lingual inclination of the maxillary anterior teeth were prominent. As for soft tissues, the change in the nasal tip was small and posterior change was large in the subnasal and upper lip areas. Nasolabial angle, nasal height, and inclination of nasal tip increased, while upper lip protrusion, nasal tip angle, and philtrum length decreased. Correlations were found between posterior changes in hard tissues and posterior changes in soft tissues. Among these, posterior changes and lingual inclination of the maxillary anterior teeth strongly correlate with posterior changes of the upper lip. ConclusionPosterior shift of the maxillary anterior segment using the WW technique is useful because it can greatly improve the protrusion of the upper lip while minimizing nasal morphological changes, and the positioning of the maxillary anterior teeth may be an important key factor.

Correlation of Clivus Length and Angle with Chronological Age, Gender, Sagittal Growth Pattern of the Jaws, and Skeletal Maturation Using Lateral Cephalometry.

Determination of remaining growth potential of patients is the most important factor in orthodontic treatment. This study aimed to assess the correlation of clivus length and angle with age, gender, sagittal growth pattern of the jaws, and skeletal maturation using lateral cephalometry. This cross-sectional study was conducted on 390 lateral cephalograms (Vatech, paX-i3D Green, South Korea) of patients aged 6 to 25 years. The patients were assigned to three groups of skeletal class I, II, III (n=130) with equal gender distribution. The clivus length and angle, Welcher angle, maxillary and mandibular effective length, sella turcica to Nasion (SN), and the angles between SN and point A (SNA), between SN and point B (SNB), and between NA and NB (ANB )were measured. Correlations of variables with age and gender, and cervical vertebral maturation stage (CVMS) were analyzed using the Pearson and Spearman's correlation tests, independent t-test, and one-way ANOVA at 0.05 level of significance. Clivus length had a significant correlation with SNA (r= 0.103, p= 0.042), SNB (r= 0.108, p= 0.033), maxillary (r= 0.547, p< 0.001) and mandibular (r= 0.589, p< 0.001) effective lengths, SN length (r= 0.586, p< 0.001), and CVMS (r= 0.697, p< 0.001). Clivus angle had a significant correlation with SNA (r= 0.105, p= 0.039), SNB (r= 0.155, p= 0.002), maxillary (r= 0.507, p< 0.001) and mandibular (r= 0.596, p= 0.001) effective lengths, SN length (r= 0.566, p< 0.001), and CVMS (r= 0.699, p< 0.001). The mean clivus length (p= 0.006) and angle (p= 0.002) were significantly higher in males, and had a significant correlation with age (r= 0.636 and r= 0.718, p< 0.001). The mean clivus length and angle were not significantly different in class I, II, III (p> 0.05). All parameters were greater in males, and increased with age (except Welcher angle). Clivus length and angle had significant correlations with position of both jaws but not with sagittal relationship.

Comprehensive treatment approach for hemifacial microsomia: Integrating orthognathic surgery with sequential customized implantation

ObjectiveThis study aims to evaluate the clinical outcomes of combining orthognathic surgery with staged patient-specific implants (PSIs) for comprehensive craniofacial asymmetry reconstruction in adult hemifacial microsomia (HFM) patients. MethodsSix adult HFM patients (1 Type I and 5 Type IIa) underwent orthognathic surgery to correct skeletal malocclusion and chin deviation. Sequential PSIs were implanted to address craniofacial asymmetry. Digital lateral cephalograms and cranial CT scans were obtained at four time points: pre-orthognathic surgery (T0), within three months after orthognathic surgery (T1), one year after orthognathic surgery and just before personalized implantation (T2), and after personalized implantation (T3). Evaluation parameters included skeletal and dentoalveolar measures, occlusal cant, chin deviation, skeletal stability, and facial contour symmetry. ResultsAt T1, no significant differences were observed in skeletal movements compared to planned surgical movements (p > 0.05). Similarly, at T2, skeletal movements did not significantly differ from those observed at T1 (p > 0.05), indicating surgical precision and stability. Analysis of skeletal and dentoalveolar parameters, occlusal cant, and chin deviation revealed significant increases in SNB, FH-NPo, and ST N vert-Pog at T1 compared to T0 (p < 0.05), along with notable improvements in chin deviation and occlusal cant (p < 0.05). Comparison of T2 to T1 showed no significant changes in SNB, FH-NPo, ST N vert-Pog, chin deviation, or occlusal cant (p > 0.05), indicating substantial postoperative stability. Following personalized implantation (T3), further significant improvements were observed in skeletal symmetry. ConclusionCombining orthognathic surgery with staged PSIs effectively reconstructs craniofacial asymmetry in adult HFM patients, achieving significant improvements in skeletal alignment, occlusal cant, and chin deviation, with stable outcomes over time.

Application of Cone-Beam Computed Tomography-Generated Cephalograms in Children and Adolescents

This study investigates the potential of cone-beam computed tomography (CBCT)-generated cephalograms as a replacement for conventional lateral cephalograms (LCs) in children and adolescents. This retrospective study included 60 individuals, equally divided into permanent and mixed dentition groups. Both groups underwent conventional LCs and CBCT scans on the same day. LCs were then derived from CBCT scans. The same examiner performed digital measurements twice, with a week’s interval, identifying landmarks and obtaining 7 angular and 5 linear measurements. In the permanent dentition group, significant differences were observed between the two imaging modalities for 6 angular and 2 linear measurements. In the mixed dentition group, significant differences were observed for 3 angular and 2 linear measurements. However, none of these differences exceeded the clinically acceptable limit of 2.0º or 2.0 mm. No significant differences in any measurement were found between the two groups (&lt;i&gt;p&lt;/i&gt; &lt; 0.05). CBCT-generated LCs demonstrated comparable results with good reliability in both dentition groups, suggesting their potential as suitable alternatives for children and adolescents who require CBCT for clinical purposes.