Anteroposterior Discrepancy Research Articles

Application of a 3D Fusion Model to Evaluate the Efficacy of Clear Aligner Therapy in Malocclusion Patients: Prospective Observational Study

Background Investigating the safe range of orthodontic tooth movement is essential for maintaining oral and maxillofacial stability posttreatment. Although clear aligners rely on pretreatment digital models, their effect on periodontal hard tissues remains uncertain. By integrating cone beam computed tomography–derived cervical and root data with crown data from digital intraoral scans, a 3D fusion model may enhance precision and safety. Objective This study aims to construct a 3D fusion model based on artificial intelligence software that matches cone beam computed tomography and intraoral scanning data using the Andrews’ Six Element standard. The model will be used to assess the 3D effects of clear aligners on tooth movement, to provide a reference for the design of pretreatment target positions. Methods Between May 2022 and May 2024, a total of 320 patients who completed clear aligner therapy at our institution were screened; 136 patients (aged 13-35 years, fully erupted permanent dentition and periodontal pocket depth <3 mm) met the criteria. Baseline (“simulation”) and posttreatment (“fusion”) models were compared. Outcomes included upper core discrepancy (UCD), upper incisors anteroposterior discrepancy (UAP), lower Spee curve deep discrepancy (LSD), upper anterior teeth width discrepancy (UAW), upper canine width discrepancy (UCW), upper molar width discrepancy (UMW), and total scores. Subanalyses examined sex, age stage (adolescent vs adult), and treatment method (extraction vs nonextraction). Results The study was funded in May 2022, with data collection beginning the same month and continuing until May 2024. Of 320 initial participants, 136 met the inclusion criteria. Data analysis is ongoing, and final results are expected by late 2024. Among the 136 participants, 90 (66%) were female, 46 (34%) were male, 64 (47%) were adolescents, 72 (53%) were adults, 38 (28%) underwent extraction, and 98 (72%) did not. Total scores did not differ significantly by sex (mean difference 0.01, 95% CI –0.13 to 0.15; P=.85), age stage (mean difference 0.03, 95% CI –0.10 to 0.17; P=.60), or treatment method (mean difference 0.07, 95% CI –0.22 to 0.07; P=.32). No significant differences were found in UCD (mean difference 0.001, 95% CI –0.02 to 0.01; P=.90) or UAP (mean difference 0.01, 95% CI –0.03 to 0.00; P=.06) by treatment method. However, adolescents exhibited smaller differences in UCD, UAW, UCW, and UMW yet larger differences in UAP and LSD (df=134; P<.001). Extraction cases showed smaller LSD, UAW, and UCW but larger UMW differences compared with nonextraction (df=134; P<.001). Conclusions The 3D fusion model provides a reliable clinical reference for target position design and treatment outcome evaluation in clear aligner systems. The construction and application of a 3D fusion model in clear aligner orthodontics represent a significant leap forward, offering substantial clinical benefits while establishing a new standard for precision, personalization, and evidence-based treatment planning in the field. Trial Registration Chinese Clinical Trial Registry ChiCTR2400094304, https://www.chictr.org.cn/hvshowproject.html?id=266090&v=1.0

Teenage Patients with Class II Subdivision Treated with Aligners and Elastics: A Retrospective Study.

Background and Objectives: This study aimed to evaluate the outcomes of Class II subdivision teenage patients treated with Invisalign® clear aligners (CAs) and elastics. Materials and Methods: A total of 23 individuals aged 14.3 ± 2.5 years were enrolled in this study. The participants were divided into Group 1 (mandibular midline deviation) and Group 2 (maxillary midline deviation). The midline deviation from the facial midline; anteroposterior discrepancy; overjet (OJ), overbite (OB), and Peer Assessment Rating (PAR) scores; upper incisor and lower incisor (L1) positions; and angulation were measured at the beginning (T0) and end (T1) of the orthodontic treatment. Results: Group 1 showed significant higher variations in OJ (-2.3 ± 2.3 vs. -0.6 ± 0.8, p < 0.001), OB (-2.1 ± 2.3 vs. -1.1 ± 1.4, p < 0.001), PAR score (-32.0 ± 11.7 vs. -27.3 ± 13.1, p < 0.001), L1-to-mandibular-plane angle (-3.6 ± 7.0 vs. -1.3 ± 3.2, p < 0.001), and interincisal angle (10.07 ± 8.7 vs. 5.9 ± 5.3, p = 0.007). The midline deviation was the only measurement with higher variation in Group 2. The average distance between the mesiobuccal cusp of the maxillary first molar and the buccal groove of the mandibular first molar was 0.3 ± 0.5 mm. Conclusions: A total of 21 patients achieved bilateral Class I (91% success rate) and demonstrated great improvement (72-96%) in PAR scores. Regardless of the etiology of malocclusion, the orthodontic correction of the Class II subdivision with CAs showed high accuracy and predictable results.

A comparison of the new parameter, “MKG angle” with ANB, Wits’ appraisal, Yen, Pi, and W angles

Objectives: The objectives of the study are to compare and assess the precision of MKG angle with ANB, Wits’ appraisal, Yen, Pi, and W angles and reproducibility between them. Material and Methods: 160 pre-treatment cephalograms of 80 skeletal class I and 80 skeletal class II patients were selected from the Department of Orthodontics and Dentofacial Orthopedics and were divided into Group 1 and Group 2. MKG angle, ANB angle, Wits’ appraisal, W, Yen, and Pi angles were measured, and MKG angle was compared with each of them for the evaluation of its precision. Results: The statistical analysis was done using SPSS software version 26.0. The mean, standard deviation, t-test, and Pearson correlation coefficient were calculated. Descriptive statistics were done to know the mean and standard deviation. The Pearson correlation coefficient was done to know the correlation between the MKG angle and other parameters in both the groups. A statistically significant difference was observed between MKG angle and all other parameters – ANB, Wits’ appraisal, YEN, W, Pi angles in general population. Conclusion: MKG angle can be used to assess the anteroposterior discrepancy but as an adjunct with other parameters.

Comparative evaluation of the reliability of MNG angle with other anteroposterior skeletal dysplasia indicators – A retrospective cephalometric study

The aim of the study was to evaluate the reliability of the MNG angle for various skeletal malocclusions and to compare and correlate it with ANB angle, Beta angle, Yen angle and W angle in Gujarati population. Lateral cephalograms of 50 Gujarati adults, were divided into three groups based on the ANB angle and the Beta angle measurements. The Yen angle, W angle and MNG angle were measured for all the cephalograms. The mean value for MNG angle was derived for each group. The one-way analysis of variance (ANOVA) and Bonferroni post hoc tests were used to compare the differences between the mean values of the 3 groups. Spearman’s correlation analysis was used to determine correlations among the five skeletal parameters. Analysis of the obtained data revealed a mean MNG angle of -1.22° ± 3.9°, 3.11° ± 2.8° and -6.0° ± 1.5° for Class I, II and III respectively. Spearman’s correlation analysis demonstrated a significant co-relation between ANB angle, Beta angle and MNG angle with a p value of ≤ 0.05 for skeletal Class I and Class II malocclusions. The MNG angle can be used as a dependable maker to assess the antero-posterior discrepancy, especially for Class II skeletal pattern.

Factors influencing young patient arrival date at the orthodontic office: a study of 456 cases

The arrival date young patient's first orthodontic consultation is unrestricted but may influence the choice of treatment plan as well as its modalities. The objective of this study was to determine the factors that influence the date of the first consultation at the orthodontic office: advice from a third party or a health professional, the patient's gender, the socioeconomic level, the actual need for orthodontic treatment, and the vertical and anteroposterior skeletal dysmorphia. Young patient's file younger than 16 years were systematically included. A Wilcoxon and Kruskal-Wallis test was performed in univariate and multivariate analysis. The threshold was 5%. 456 young patients were included. Anteroposterior skeletal discrepancy, referral by an acquaintance, and socioeconomic level appeared to be factors influencing patient arrival date. Gender, actual need for orthodontic treatment, referral from a health professional, and vertical skeletal discrepancy did not influence the arrival date at the office. The date of consultation is not related to the actual orthodontic treatment need. Word-of-mouth seems to play an important role. Patients seem to relate an anteroposterior discrepancy to the need to consult an orthodontist, but do not relate it to vertical discrepancy, although ventilation may be related to severe dysmorphia. This study encourages more communication about orthodontic treatment indications with patients and caregivers.

Advansync in management of class II malocclusion: A systematic review

Class II malocclusions are of interest to practising orthodontists since they constitute a significant percentage of the cases they treat. In individuals with Class II malocclusions, there is an anteroposterior discrepancy between the maxillary and mandibular dentitions, which is usually accompanied by a skeletal discrepancy. In such malocclusions, a functional appliance (myofunctional or fixed functional) is chosen as a treatment method depending on the severity and need of the particular case. This systematic review aims to evaluate the dental-alveolar, skeletal and soft tissue changes with the use of Advansync™ (A Class II corrector/ fixed functional appliance) in the treatment of Class II malocclusion. A literature search was done on Pubmed, EbscoHost , Google Scholar, Science Direct. This was conducted by two reviewers independently and any conflicts in results were managed through discussion. A Risk of Bias was done for the final articles included in the study. A total of 3,099 records were identified while searching through the database based on Mesh terms and search strategies. Based on the inclusion and exclusion criteria’s the total articles which were eligible for the systematic review were six. As the study was specific in terms of age and gender there was a high risk of selection bias but low risk of reporting bias.Out of the 6 studies, 5 had a low risk of bias and based on their cumulative findings, the effectiveness of Advansync is similar to those of other Class II correctors. The advantage of Advansync over other correctors is that the appliance saves treatment time and can be incorporated from the second month of treatment thereby shortening the duration of treatment.Fixed Class II correctors are used widely in Orthodontics. The selection of the appropriate appliance for the patient is the need of the hour. Thus, this systematic review gives us an insight on the use of Advansync in Class II correction.

Temporomandibular joint disorders in skeletal class II patients referred to orthognathic surgery: A cross-sectional study.

The aim of this study was to assess the prevalence of Temporomandibular Disorders (TMD) in subjects with skeletal class II dentofacial deformity referred for orthognathic surgery, as well as to elucidate its association with sociodemographic and psychosocial features. This was a cross-sectional study using the Research Diagnostic Criteria for Temporomandibular Disorders. The sample comprised class II skeletal patients referred to an Oral and Maxillofacial Surgery center in the Brazilian Northeast. Seventy-three subjects were enrolled and completed the data collection, which consisted of a physical examination according to Axis I of the Research Diagnostic Criteria for Temporomandibular Disorders and facial analysis. Women represented 82.2% of the sample. Among the assessed subjects, 68.5% were already undergoing orthodontic treatment, and the mean overjet of patients was 6.97 mm. The prevalence of TMD in this sample was 46.6%, with muscular disorders being the most common. Patients with an anteroposterior discrepancy greater than 7 mm showed a higher occurrence of TMD (p = 0.017). This study demonstrated a high prevalence of TMD in skeletal class II patients referred for orthognathic surgery, especially in those with a pronounced overjet, being Group I (muscular disorders) and Group III (degenerative disorders) the most prevalent.

TADS assisted camouflage orthodontic treatment of class ii malocclusion in a non-growing patient- A case report

In individuals with Class II malocclusions, there is an anteroposterior discrepancy between the maxillary and mandibular dentitions, which may or may not be accompanied with a skeletal discrepancy, the most effective treatment option to eliminate is by modified three-piece base arch combined with TADS for simultaneous deep bite correction and en masse retraction.The present case report showcases the treatment results and biomechanics involved for en masse retraction and intrusion of anterior teeth using three-piece intrusion arch and temporary anchorage device.The modified three-piece base arch combined with TADS is effective in controlled translation and intrusion of anteriors and would be a preferable mechanotherapy in low angle case with deep bite, proclined anteriors and Class II malocclusion.

Combined Orthodontic and Prosthetic Treatment of a Patient with Angle Class II Division 1 Malocclusion: A Case Report

Abstract Skeletal class II division 1 malocclusion is primarily characterized by maxillary protrusion, mandibular retrusion or a combination of both. Treatment modalities for these patients are different depending on the age and the severity of the case. In adult patients with skeletal class II division 1, where the discrepancy is very severe, orthodontic and orthognathic surgery combined are often necessary to ensure an appropriate treatment, while prosthodontic treatment may be a challenge due to the skeletal discrepancies of the maxilla and the mandible. This clinical report presents a 45-year-old patient with a diagnosis of Angle Class II division 1 malocclusion. After clinical and radiographic observation and consultation with an orthodontist and maxillofacial surgeon, a combination of surgical and orthodontic therapy was proposed. Considering that the patient refused the surgical procedure due to fear, orthodontic therapy was carried out first, which improved the aesthetic and functional characteristics, but did not give results in increasing the vertical dimension of the occlusion. Therefore, further therapy was prosthetic, and was carried out by making all-ceramic maxillary and mandibular fixed dental prostheses; the patient was successfully rehabilitated and the anteroposterior discrepancy between the dental arches was corrected. Combined orthodontic and prosthetic treatment can be a good option in the complex treatment of patients with skeletal class II division 1 malocclusion providing functional rehabilitation of the stomatognathic system and improving facial appearance and the quality of life of the patient.

Treatment of a severe skeletal Class II malocclusion through growth modification: a problem-oriented case report

Abstract A skeletal Class II malocclusion is an anteroposterior discrepancy resulting from a combination of skeletal and dental factors. In adolescent patients, it is possible to leverage their growth potential to address bone deformities and minimise the need for future surgical interventions. In the present case report, a combination treatment approach was adopted which included a functional appliance, fixed appliances, and temporary anchorage support, to treat a 13-year-old Chinese male with a severe skeletal Class II malocclusion. After a treatment duration of 36 months, the patient achieved a favourable occlusion and an improved facial profile. Subsequently, a stable occlusal relationship and balanced facial proportions were maintained during a 2-year retention period.

Predictability of Wits appraisal, ANB, Beta, Yen, W, µ and Pi angle as indicators of anteroposterior dysplasia in Jharkhand population

: The measurements for assessing the antero-posterior discrepancy between the apical bases are many with their individual benefits and shortcomings. So, it is very important to categorize the reliability of the major diagnostic criteria for successful planning of treatment and to fore see the outcome. The present study assesses the predictability of Wits appraisal, ANB, Beta, Yen, W, µ and Pi angles as an indicators of anteroposterior dysplasia. A total of 120 lateral cephalograms of skeletal Class I, II and III patients were selected based on Down’s facial angle and then tracing was carried out manually to measure Wits appraisal, ANB, Beta, Yen, W, µ and Pi angles. Analysis of variance and correlation coefficient analysis were done to assess the significance of association between these variables. Yen angle is highly predictable and a homogenously distributed angular parameter used to assess sagittal discrepancy. The most desirable differentiation results among the three skeletal relationship were represented by Beta angle followed by Yen angle. Statistically significant correlation among the seven parameters for skeletal Class I relationship were shown by Yen and W angle, for skeletal Class II relationship by Beta angle and µ angle and for skeletal Class III relationship by Beta angle and W angle. No statistically significant correlation existed between Yen Angle and Beta Angle in all the three groups. Yen angle was found to have the most homogenous and predictable parameter. A statistically significant correlation for skeletal Class I relationship were observed between Yen and W angle, for skeletal Class II relationship between Beta and µ angle and for skeletal Class III relationship between Beta angle and W angle and they can be used interchangeably in assessing skeletal jaw relationship.

Photographic Frankfort plane subnasale pogonion (FSA) angle for assessment of anteroposterior discrepancies in malocclusion subjects: A prospective study.

Anterior-posterior discrepancy assessment is a crucial component of orthodontic diagnosis and is often carried out using hard tissue cephalometric analysis. The purpose of this study was to compare the photographic Frankfort plane subnasale pogonion (FSA) angle with established cephalometric parameters to determine the accuracy of the angle in determining maxillomandibular anteroposterior discrepancies. In this prospective study, a total of 60 subjects, 20 in each skeletal sagittal malocclusion, were included in the final sample based on the selection criteria. Both photographic and cephalometric records were taken, and the parameters assessed were the beta angle, Steiner's analysis, the ANB (A point- Nasion- B point) angle in the cephalograms, and the FSA angle in the profile photographs. Statistical analysis was done with SPSS software. The correlation between the measured parameters was assessed using Pearson's correlation test. A high positive and significant correlation between the FSA angle and beta angle (r = 0.793) was noted, and a high negative and significant correlation between the FSA angle and ANB angle (r = -0.848) was noted. The photographic FSA angle can be used as a reliable parameter to diagnose anteroposterior discrepancies.

Early Orthosurgical Treatment of a Skeletal Class III: Can the Self-Esteem Be Improved?

Young patients with a skeletal Class III malocclusion with a strong psychological and appearance impact may require surgical correction during their growth. This case report describes the orthosurgical treatment of a 11-year-old boy with history of bullying, presenting severe Class III skeletal malocclusion, anterior cross-bite and mandibular prognathism. He also had significant vertical and anteroposterior discrepancies and a concave profile with prominent lips. The treatment plan included extraction of the first premolars, a maxillary LeFort I osteotomy and a mandibular bilateral sagittal split osteotomy. The orthodontic treatment combined with the two-jaw surgery improved his jaws alignment, occlusal function, and the most important: his self-esteem and quality of life.

English

BACKGROUND Skeletal class II division 1 malocclusion is an antero posterior discrepancy between maxilla and mandible which is usually treated by functional appliances when the patient is in the growing phase. It has been shown that these functional orthodontic appliances may lead to pressure on the oral mucosa, soft tissue tension, oral constriction, toothache and pain. They may also lead to fatigue or to functional speech and respiratory disorders, and they may affect the appearance of the face. All of these undesired consequences affect the patients’ degree of compliance in a negative manner, and may in turn affect the patients’ perception towards the treatment. This study was conducted to investigate patient perception of treatment need, appliance acceptance, expectations of treatment influence on oral health, value of dental aesthetics and information concerning treatment procedures. METHODS Total 30 samples were selected 15 samples were cases treated with twin block appliance and other 15 samples were treated with clear block appliance. After 8 months of treatment, a questionnaire survey was conducted assessing discomfort, expectations and experiences of all patients being treated with clear block appliance and twin block appliance. RESULTS Clear block seemed to be better with regard to all the parameters used in the study but on statistical analysis the difference between the two groups was insignificant. CONCLUSIONS Clear block appliance was designed to increase the compliance of the patient. However, clear block and twin block appliance have similar effects. KEY WORDS Class II, Clear Block, Twin Block

Influence of Facial Morphology on Masticatory Function and Quality of Life in Elders Using Mandibular Overdentures: 3-Year Results.

Background: Facial types may interfere in the oral health-related quality of life (OHRQoL) and masticatory performance of implant-retained mandibular overdenture (IMO) wearers.Purpose: Investigate the medium-term changes in the masticatory function (MF) and OHRQoL parameters of IMO users, as a function of facial pattern, anteroposterior skeletal discrepancy, and sex.Methods: Forty IMO users, most of them Caucasian (90%) with average age of 69.17 years were classified according to their facial pattern and antero-posterior discrepancy prior to rehabilitation. MF was evaluated by the multiple sieves method to determine the average particle size (X50), heterogeneity (B) and masticatory efficiency (ME, calculated as the percentage of material retained in the 5.6 and 2.8 mm sieves), using Masticatory performance (MP) and swallowing threshold (ST) tests. OHRQoL was measured by applying the dental impact on daily life (DIDL) questionnaire. The data were analyzed by Wilcoxon-paired tests to analyze changes in MF parameters over time, and mixed-effect multilevel regression models were employed to verify differences between groups.Results: Significant changes were still observed in the 3rd year for the ST test with improvements in B for Mesofacial and in time for Dolichofacial individuals, while ME_2.8 deteriorated for Brachyfacial participants. B values of Class I and male individuals improved and brachyfacial individuals still presented worse homogenization (B) than Mesofacial participants in both masticatory tests. Class II and III participants still showed improvements in ME_5.6 and time compared to Class I despite increases in X50. Class II individuals needed less cycles than Class I in the 3rd year. Brachyfacial participants scored lower in the Appearance domain than Mesofacial ones in the 3rd year. Dolichofacial participants and Class III patients scored lower in the Oral Comfort domain than Mesofacial and Class I, respectively. In addition, age influenced the Pain, Oral Comfort and General Performance domains in the 3rd year.Conclusions: Differences in facial morphology continue to influence the MF and OHRQoL outcomes in the 3rd year, and age influenced some OHRQoL domains. Brachyfacial individuals continue to benefit least from rehabilitation with IMO according to masticatory parameters.

Adenotonsilectomia e Classe II esquelética – estudo de casocontrole

Introduction: The maxillomandibular lateral growth imbalance with mandibular retrusion related to the maxilla indicates the skeletal Class II pattern. This craniofacial morphological abnormality is often attributed to nasorespiratory obstruction due to pharyngeal and palatine tonsils hypertrophy. The adenotonsillectomy is indicated to young patients with respiratory obstruction. However, there is no information in the scientific literature concerning the impact of tonsils surgically removal on craniofacial growth and development. Objective: To identify the association between adenotonsillectomy and skeletal Class II. Material and Methods: An unpaired case-control study was performed. Adult subjects who agreed to participate filled a questionnaire and after identification of the skeletal pattern through radiographic cephalometric analysis were allocated into two groups: CASE GROUP composed of 23 subjects with skeletal Class II malocclusion and CONTROL GROUP composed of 27 subjects without skeletal Class II malocclusion. With specific software the images were evaluated and measured to compare craniofacial measurements between the experimental groups and this data was interpreted to verify the association between skeletal Class II and the occurrence of adenotonsillectomy in early childhood. Results: the adenotonsillectomy demonstrated protective potential for skeletal Class II development due to a strong epidemiological association between adenotonsillectomy and skeletal Class II anteroposterior discrepancy (ORC = 0.33), without gender interference (ORA = 0.91). Conclusions: Among the long-term benefits of performing adenotonsillectomy in early childhood, it may be considered the prevention of craniofacial growth alterations such as Class II maxillomandibular discrepancy.

Changes in Pharyngeal Airway After Mandibular Setback Surgery: A Retrospective Cephalometric Study

Aim: To cephalometrically evaluate the alterations taking place in the pharyngeal airway space, hyoid bone, soft palate, and head posture after mandibular setback surgery (bilateral sagittal split osteotomy) for correction of mandibular prognathism, as well as to evaluate the immediate postsurgical and more than 6 months postsurgical adaptations of these structures. Setting and Design: A retrospective cephalometric study. Materials and Method: The study group consisted of 40 nongrowing patients (20 females and 20 males) with mandibular prognathism and ANB less than or equal to –2 degree for which mandibular setback surgery by bilateral sagittal split ramus osteotomy was performed along with fixed appliance therapy. There presurgical (T1), immediate postsurgical (T2), and more than 6 months postsurgical (T3) lateral cephalograms were analyzed. Statistical Analysis Used: Intragroup comparison was done by paired t-test. Results: Skeletal measurements after orthognathic surgery remained stable in the long term. It was evident that mandibular setback surgery narrowed the pharyngeal airway; however, these changes were not significant except at the base of the tongue. During the follow-up airway measurements at the base of the tongue, the intersection of tongue at the inferior border of mandible and the vallecula increased but they did not reach the presurgical values. Soft palate length increased significantly after surgery. Angulation of soft palate to nasal line also increased significantly following surgery but decreased during follow-up. Extension of the head occurred after surgery which was maintained even at long term. Conclusion: Careful analysis of airway should be performed, particularly in connection with large anteroposterior discrepancies and in those who have risk factors for development of obstructive sleep apnea. Such cases should be corrected by combined maxillary and mandibular osteotomies.

Comparison of ANB Angle, Yen Angle and W Angle in Chinese Population

Introduction: An accurate, reliable and stable method of accessing sagittal jaw relationship with cephalometric analysis is essential in orthodontic diagnosis and treatment planning. Many methods have been developed to assess antero-posterior jaw discrepancy but they all have some shortcomings including ANB angle. Thus the purpose of this study is 1) To provide mean values and standard deviations for ANB angle, Yen angle and W angle for a sample of skeletal Class I, II and III Chinese males and females malocclusion patients; 2) To verify the existence of sexual dimorphism; 3) To compare these three methods for assessing sagittal jaw relationship 4) To assess the correlation between these and 5) To find out which is the most reliable amongst them.&#x0D; Materials &amp; Method: 120 pretreatment lateral cephalograms of Chinese patients, including both males and females between 18 to 25years old, were collected from the Department of Orthodontics; Wuhan Union Hospital which were divided into 3 groups as Class I, II and III skeletal pattern. Each pattern consists of 40 samples. The values of the males and females were compared with independent t-test while the inter-group comparisons were conducted with ANOVA and Tukey’s test. Pearson correlation test was performed to correlate between these angles.&#x0D; Result: There were no statistically significant differences between the mean values of these angles in male and female within the groups in all three classes. ANOVA analysis showed significant differences were found in ANB angle, Yen angle and W-angle in all the three Groups. Strong correlation existed between Yen angle and W angle.&#x0D; Conclusion: There is no existence of sexual dimorphism in our study. ANB angle is affected by growth of Nasion while Yen angle is affected by rotation of jaws. ANB angle is easy to assess while W angle is most stable and reliable.

The National Dental Practice-Based Research Network Adult Anterior Open Bite Study: Treatment recommendations and their association with patient and practitioner characteristics

This aim of this paper is to describe and identify the practitioner and patient characteristics that are associated with treatment recommendations for adult anterior open bite patients across the United States. Practitioners and patients were recruited within the framework of the National Dental Practice-Based Research Network. Practitioners were asked about their demographic characteristics and their treatment recommendations for these patients. The practitioners also reported on their patients' dentofacial characteristics and provided initial cephalometric scans and intraoral photographs. Patients were asked about their demographic characteristics, previous orthodontic treatment, and goals for treatment. Four main treatment groups were evaluated: aligners, fixed appliances, temporary anchorage devices (TADs), and orthognathic surgery. Extractions were also investigated. Predictive multivariable models were created comparing various categories of treatment as well as extraction/nonextraction decisions. Ninety-one practitioners (mostly orthodontists) and 347 patients were recruited from October 2015 to December 2016. Increased aligner recommendations were associated with white and Asian patients, the presence of tongue habits, and female practitioners. TADs were recommended more often in academic settings. Recommendations for orthognathic surgery were associated with demographic factors, such as availability of insurance coverage and practitioner race/ethnicity, and dentofacial characteristics, such as anteroposterior discrepancies, more severe open bites, and steeper mandibular plane angles. Extraction recommendations were largely associated with severe crowding and incisor proclination. Both doctorand patient demographic factors, as well as dentofacial characteristics, were significantly associated with treatment recommendations for adult anterior open bite patients.

Correcting the Anteroposterior Discrepancy of Class Ⅱ Patient with Overject by the Vertical Control of Miniscrew

Background: While various orthodontic appliances were designed to manage the anteroposterior and vertical discrepancy, miniscrew was one of the powerful appliances and was widely utilized as anchorage to treatment the anteroposterior relationship. Method and Result: In the study we treated the severe Class Ⅱ skeletal discrepancy subject with protrude upper incisors and mandibular hypoplasia by the vertical control with the miniscrew. After two years treatment, all the objectives were achieved. The skeletal Class Ⅱ discrepancy was improved (ANB 6.3), the protrude upper incisors were treated (U1 angulation 92.8, U1-L1 120.7) and the occlusive plan was leveled (Occ Plane 8.2). Class Ⅰ molars and canines relationship were obtained. Conclusion: The vertical control was vital for the correction of anteroposterior discrepancy. The anteroposterior, vertical and transverse dimension and the time, especially the long term of post-treatment stability, interacts with each other.