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AIM: The purpose of this study was to evaluate the mandibular growth and/or projection following maxillary incisor proclination, overbite correction, and maxillary dentoalveolar expansion without the use of any class II mechanics, in growing class II division 2 patients treated with clear aligners. MATERIALS AND METHODS: Before and after treatment cone-beam computed tomographic (CBCT) generated lateral and posteroanterior cephalograms of thirty-two patients with skeletal class II division 2, 16 in the treatment group and 16 in the untreated group, were reviewed to evaluate treatment-related changes. Upper incisors were proclined and protruded, as well as upper arch expansion and overbite correction were performed as part of their regular treatment. Cephalometric analysis was performed to evaluate skeletal and dental changes. Unpaired statistical t-tests were performed to determine if significant skeletal class II correction was achieved in the treatment group. RESULTS: In the treatment group, after treatment, the upper incisors became more proclined and protruded, and the inter-molar width increased while the overbite was reduced compared to the control group. An increase in skeletal mandibular growth and forward projection was also observed, thus contributing to an improvement of the sagittal skeletal relationship as evidenced by ANB and Wits values compared to the control group. CONCLUSION: A combination of upper incisor proclination, correction of deep overbite, and maxillary dentoalveolar expansion using clear aligners appears to contribute to an improvement of the skeletal class II relationship in growing patients with class II division 2. CLINICAL SIGNIFICANCE: This study shows that unlocking the mandible by correcting a deep overbite, proclining upper incisors, and expanding the upper arch in growing class II division 2 patients can improve skeletal class II using clear aligners. How to cite this article: Mirzasoleiman P, El-Bialy T, Wiltshire WA, et al. Evaluation of Mandibular Projection in Class II Division 2 Subjects Following Orthodontic Treatment Using Clear Aligners. J Contemp Dent Pract 2024;25(4):295-302.

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The peptidoglycan (PG) layer, a core component of the bacterial cell wall, has been retained in the Physcomitrium patens chloroplasts. The PG layer entirely encompasses the P. patens chloroplast, including the division site, but how PG biosynthesis cooperates with the constriction of two envelope membranes at the chloroplast division site remains elusive. Here, focusing on the PG synthase penicillin-binding protein (PBP), we performed cytological and molecular analyses to dissect the mechanism of chloroplast division in P. patens. We showed that PBP, acting in the final step of PG biosynthesis, is likely a chloroplast inner envelope protein that can aggregate at mid-chloroplasts during chloroplast division. Physcomitrium patens had five orthologs of PLASTID DIVISION2 (PDV2), an outer envelope component of the chloroplast division complex. Our data indicated that PpPDV2 proteins interact with PpPBP and are responsible for recruiting PpPBP to the chloroplast division site, in addition to PpDRP5B. Furthermore, we found that PBP deletion and carbenicillin application restrain constriction of the chloroplast division complex, rather than its assembly. This work provides direct molecular evidence for a link between chloroplast division of P. patens and PG biosynthesis and indicates that PG biosynthesis is required for the constriction of the chloroplast division apparatus in P. patens.

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This case report describes a 19-year-old man presented with a 5.7-mm deep overbite, Class II division 2 malocclusion with the right upper maxillary canine completely buccal ectopia, deviated midline in the upper arch, severe crowding and retroclination of the maxillary and mandibular incisors. The patient was treated with clear aligners to correct the Class II relationship and the deep overbite. A series of clear aligners were used to move bilateral maxillary molars distally with unilateral mini-screw anchorage. The final results showed that clear aligners with mini-screws could effectively achieve the required upper distal molar movement thanks to a reasonable design of the stages and anchorage. The treatment was completed in 19 months and the patient was satisfied with the treatment outcome in this context of mild to moderate Class II division 2 malocclusion.

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BACKGROUND: In some countries, enrolled nurses (also known as Licensed Practical Nurses) have become essential members of the healthcare team, supporting registered nurses to address patient care needs. Registered nurses' readiness to practice is well documented in the literature, however, less is known about the preparedness of enrolled nurses for practice. OBJECTIVE: To explore and synthesize the available evidence on the graduate enrolled nurse practice readiness upon completion of their nursing qualification and at the time of entering the nursing workforce. DESIGN: A scoping review was conducted. DATA SOURCES: Databases such as CINAHL Complete, Directory of access journal, Cochrane Library, Medline, PubMed, Scopus, Web of Science, ProQuest and Google scholar were searched. REVIEW METHOD: The review was conducted using The Joanna Briggs Institute Methodology for Scoping reviews. RESULTS: Seven studies were identified for inclusion and two themes were constructed as 'ambiguous roles and expectations' and 'lack of educational preparation'. Findings from the selected studies showed a lack of clarity on the role of an enrolled nurse. In some healthcare settings, enrolled nurses were expected to undertake the same role as registered nurses. Furthermore, it was expected that enrolled nurses would be educationally prepared to work in specialty areas such as mental health, acute care and aged care upon completion of their studies. Though, none of these studies provided any conclusive evidence of whether enrolled nurses were ready to transition to practice. CONCLUSION: In line with the limited evidence, there is a need to undertake further studies to understand the graduate enrolled nurse practice readiness from graduates' and industry stakeholders' perspectives. The findings will assist the education providers to strengthen their curriculum and health industry to support enrolled nurse transition to practice.

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AIM AND OBJECTIVE: To evaluate and compare the position of the tongue from rest to centric occlusion in subjects with skeletal class II division 1 and skeletal class II division 2 malocclusions with subjects of skeletal class II normal occlusion. MATERIAL AND METHODS: The study was conducted on 30 individuals equally divided into three groups of skeletal class II division (div) 1, skeletal class II div 2, and skeletal class I normal occlusion. The study was conducted on two lateral cephalograms for each subject: one taken at rest and one in centric occlusion. RESULTS: On evaluation of tongue posture, a statistically significant difference was observed at the middle portion of the tongue in class II div 1 malocclusion, and at the posteromedial portion of the dorsum of the tongue in class II div 2 skeletal malocclusions as the tongue moved from rest to centric occlusion. While statistically significant differences were found between class II div 2 malocclusion and class I normal occlusion, no statistically significant differences were observed between class II div 1 and class II div 2 malocclusions. CONCLUSION: Tongue position was observed to be the same in both class II div 1 and class II div 2 malocclusions, with no statistically significant differences. However, a great change was seen in the tongue position from rest to centric occlusion.

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INTRODUCTION: The case in this study had moderate hypodontia, with both lower lateral incisors and the lower-left second premolar missing. A Class II division 2 relationship with severe crowding in the upper arch and a traumatic deep bite over a skeletal I base complicated the occlusion. MATERIALS AND METHODS: The plan was to extract the upper first premolars to relieve upper arch crowding and the lower-left impacted second premolar to preserve the bilateral class I molar relationship. A class I occlusal relationship was achieved through space opening in the lower lateral incisors region and space closure in the upper and lower premolars regions. RESULTS: The use of orthodontic screws for bite opening and anterior segment retraction, in conjunction with bi-metric slot size selection in bracket prescription, was effective in controlling incisor inclination and interincisal angle. The use of an implant fixture before beginning the finishing stage allowed for a reduction in total treatment time and facilitated the provision of the final prosthesis before debonding the case. As a result, the patient was able to receive a satisfactory occlusion on the day of debonding. CONCLUSION: This case of moderate hypodontia was successfully resolved by combining space closure and space opening effectively. To solve the arch problems in such Class II division 2 cases with severe crowding, extractions were required. To complete the case, this was combined with intrusive and retractive mechanics. In hypodontia cases, implants are an excellent choice for both aesthetics and functional restoration.

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Date of birth>09/06/2004; sex: female. Pre-treatment documents>13years 4months old: 07/07/2017. Diagnosis>Skeletal class II with mandibular retrusion, normodivergent facial pattern; class II division 2. Treatment planning>bimaxillary buccal fixed appliance. Duration of active treatment>29months. Post-treatment documents>15years 6months; 20/12/2019. Post-retention documents>16years 7months old; 04/01/2021. Retention period>2years 9months and still continued.

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BACKGROUND: The predictability of incisor movement achieved by clear aligners among Class II division 2 patients is poorly understood. The aim of this retrospective study was to determine the effectiveness of clear aligners in proclining and intruding upper incisors and its influencing factors. METHODS: Eligible patients with Class II division 2 malocclusion were included. For clear aligner therapy, three types of incisor movements were designed: proclination, intrusion and labial movement. Pre-treatment and post-treatment dental models were superimposed. The differences between predicted and actual (DPA) tooth movement of incisors were analyzed. Univariate and multivariate linear regression were used to analyze the potential influencing factors. RESULTS: A total of 51 patients and their 173 upper incisors were included. Actual incisor proclination and intrusion were less than predicted ones (both P < 0.001), while actual labial movement was greater than predicted one (P < 0.001). Predictability of incisor proclination and intrusion was 69.8% and 53.3%, respectively. Multivariate linear regression revealed that DPA of proclination was significantly positively associated with predicted proclination (B = 0.174, P < 0.001), ipsilateral premolar extraction (B = 2.773, P < 0.001) and ipsilateral canine proclination (B = 1.811, P < 0.05), while negatively associated with molar distalization (B = - 2.085, P < 0.05). The DPA of intrusion was significantly positively correlated with predicted intrusion (B = 0.556, P < 0.001) while negatively associated with labial mini-implants (B = - 1.466, P < 0.001). The DPA of labial movement was significantly positively associated with predicted labial movement (B = 0.481, P < 0.001), while negatively correlated with molar distalization (B = - 1.004, P < 0.001), labial mini-implants (B = - 0.738, P < 0.001) and age (B = - 0.486, P < 0.05). CONCLUSIONS: For Class II division 2 patients, predicted incisor proclination (69.8%) and intrusion (53.3%) are partially achieved with clear aligner therapy. Excessive labial movement (0.7 mm) of incisors may be achieved. Incisor movement is influenced by predicted movement amount, premolar extraction, canine proclination, molar distalization, mini-implants and age.

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Condylar displacement and remodelling are phenomena closely related to orthognathic surgery and critically involved in occlusal and skeletal stability. The aim of the present case report is to describe over time condylar displacement and surface remodelling after bilateral split sagittal osteotomy (BSSO) in an adult patient with severe class II skeletal malocclusion treated with ortho-surgical approach. A male of 21years comes to our observation. The extraoral examination shows a symmetrical square-shaped face, a convex profile, an acute nasolabial angle and a deep labiomental fold. Intraoral examination reveals a class II division 2 with a 2mm deviation of the mandibular midline to the left and the presence of a scissor bite of the bicuspids between quadrants II and III. The Spee curve and overbite are extremely accentuated (OV 14.3mm) as the overjet (11.1mm). Axiographic reconstructions of CBCT show a normal shape and position of both condyles. The cephalometric analysis shows a reduced lower facial height, a normal upper jaw position, a mandibular underdevelopment masked by a very developed symphysis and an extremely low divergence (FMA 11.2°). BSSO for mandibular setback was performed in the 13th month of orthodontic therapy. Original CBCT data before surgery (T0), at the end of treatment (T1), 2years postoperatively (T2) and 5years postoperatively (T3) were collected and reconstructed for 3-dimensional (3D) qualitative analyse. At the end of the surgical-orthodontic treatment (26months), good function and good aesthetics were achieved. The qualitative and comparative analysis of the superimpositions and the cuts made on the CBCT at T0, T1, T2, T3 showed a physiological remodelling and adaptation of the condyles.

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The aim of this case report is to illustrate the fixed orthodontic, surgical and periodontal implant management of a young adult with multiple agenesis associated with a class II division 2 malocclusion. The challenge here was the multidisciplinary synchronisation in order to achieve a coordinated treatment with the best possible aesthetic, prosthetic and functional prognosis. The patient suffered from a total of 10 agenesis including third molars and underwent implant replacement with bone grafting and periodontal planning of the 6 missing premolars. The orthodontic treatment lasted 22months and was followed by a period of just under a year for periodontal and implant prosthetic completion. The 3-year follow-up after the orthodontic phase showed an excellent prognosis in terms of aesthetics, function and stability.

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Resumo A correção da sobremordida profunda com o uso de alinhadores ortodônticos é um desafio para o ortodontista. O sucesso do tratamento depende de mecânicas auxiliares para melhor controle dos movimentos desejados. O objetivo do presente artigo foi descrever um caso clínico sobre a correção da sobremordida profunda associada a má oclusão dentária de Classe II, tratada com alinhadores ortodônticos. A paciente adulta apresentava Classe II, divisão 2 e subdivisão direita, linha média inferior desviada para direita, sorriso gengival e sobremordida exagerada, com apinhamentos em ambos os arcos. Ao final do tratamento, correta relação de sobremordida e sobressaliência foi adquirida, assim como relação molar e canino de Classe I, linhas médias coincidentes e adequado arco do sorriso, mantendo simetria e estética facial. Considerando as limitações do uso de alinhadores para a correção da sobremordida profunda, o caso apresentou resultados satisfatórios, com oclusão, função e relação estética adequadas. O correto plano de tratamento auxiliado aos acessórios ortodônticos e colaboração do paciente, tornaram possível a correção da sobremordida e Classe II com alinhadores ortodônticos. (AU)

Abstract Correcting deep overbite using orthodontic aligners is a challenge for orthodontists. Successful treatment depends on auxiliary mechanics to a better control of the desired movements. The aim of this article was to describe a clinical case of deep overbite correction associated with Class II malocclusion, treated with orthodontic aligners. The patient presented with Class II, division 2, and right subdivision, lower midline deviated to the right, gummy smile, and exaggerated overbite, with crowding in both arches. At the end of treatment, a correct overbite and overjet relationship were achieved, as well as a Class I molar and canine relationship, coincident midlines and an adequate smile arch, maintaining facial symmetry and aesthetics. Considering the limitations of using aligners to correct deep overbite, the case presented satisfactory results, with adequate occlusion, function and aesthetic relationship. The correct treatment plan, aided by orthodontic accessories and the patient's cooperation, made it possible to correct the overbite and Class II with orthodontic aligners(AU)

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A patient with a Class II division 2 malocclusion is presented, illustrating the application of a modified double J retractor (DJR) and palatal miniscrews along with clear aligners to correct the malocclusion and normalize the incisor torque. In terms of incisor torque recovery, a nonextraction approach might be a good choice if the Class II correction could be successfully achieved with total arch distalization. When maxillary molar distalization was limited by anatomical boundaries, the treatment plan was changed to bilateral maxillary first premolar extractions, which led to even more retroclination of the maxillary incisors after space closure. Anterior interdental miniscrews were used to intrude the maxillary incisors. A modified DJR and palatal miniscrews were used to regain torque and achieve palatal root movement of the maxillary incisors. The treatment effects and biomechanical designs were evaluated for torque recovery of the retroclined maxillary incisors.

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Background Smiling is one of the effective ways for people to express their feelings. It is an integral part of the diagnosis and planning and a key point of the treatment objectives in orthodontic care. Many factors are associated with a pleasant smile, such as correct anatomy, gingival health, and teeth proportion. Therefore, different malocclusion classes can affect the characteristics of smile esthetics. This study aimed to evaluate the effect of skeletal class II malocclusion on the characteristics and dynamics of the smile in the sagittal and frontal planes. Methodology The study sample included 60 patients comprising three groups of malocclusion classes, namely, Class I, Class II division 1, and Class II division 2. A video recording was taken for 5-10 seconds for each patient using a specific camera mounted at a fixed distance from the imaged face. Two facial expressions were captured for each patient, one representing the lips at rest and the second representing the unrestricted natural smile. The facial still images were derived from the streaming video recording, and two images were chosen for each plane (the frontal plane and the sagittal plane) for each patient. In total, 12 variables were assessed on these captured images. One-way analysis of variance (ANOVA) was used to detect significant differences between the three groups. Results There were statistically significant differences in some of the measured variables. The mean values of thickness of the upper lip, commissure height, gum width, maxillary incisor display, and interlabial gap were greater in the Class II division 1 group than in the other two groups. The proclined incisors were evident in the Class II division 1 group, while the retroclined incisors were evident in the Class II division 2 group. Conclusions The skeletal Class II malocclusion influences the characteristics of the smile, either assessed on the anterior or lateral imaging angles, in addition to its influence on the resting position of the lips. Orthodontists should always analyze patients' facial expressions, including those related to the upper and lower lips at rest and when patients smile naturally. Depending on the results of this analysis, treatment planning could be built to improve the characteristics of the natural smile in patients with Class I and Class II malocclusions.

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AIM: The aims of our research were as follows: 1) Description of changes in the position of the upper and lower lips, as a result of the change in the position of upper and lower incisors after orthodontic treatment of malocclusion of Class II, division 2 type. 2) Determination of correlation between changes in the position of lips and incisors in the profile of the face after orthodontic treatment of malocclusion of Class II, division 2 type.MATERIALS AND METHODS: Our study analyses the documentation of 115 patients with malocclusion of Class II, division 2 type treated with a fixed orthodontic appliance in the upper and lower dental arches at the Orthodontic Department of the Clinic of Dentistry in Olomouc from January 1, 1996 to December 31, 2017. There were 78 women and 37 men aged 11 to 36 years included in the database. Cephalometric images of patients from the group taken before and after the treatment were used for the purpose of cephalometric analysis according to Kamínek (1) and Burstone's analysis (2) of soft tissues. Subsequently, all output data were processed statistically. RESULTS: While the protrusion of the incisors after treatment of malocclusion of Class II, division 2 type was 3 mm, the facial profile showed statistically significant changes in soft tissues in the ventral direction by 1 mm on average just in the area of the upper and lower lips, which means a shift corresponding to one third of teeth movement. CONCLUSION: A statistically significant change in the position of incisors, soft tissues as well as correlation between changes in hard and soft tissues in the face profile after orthodontic treatment of malocclusion of Class II, division 2 type were demonstrated. The more the incisors were inclined, the more the lips moved forward, and the patient's profile turned out to be aesthetically improved (Tab. 2, Fig. 3, Ref. 39).

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Introduction The objective of this observational study is to compare the dental and skeletal changes that occur following the release of incisor locking in class II division 2 patients in the decelerating phase of the adolescent growth spurt. Materials and methods Lateral cephalograms of 17 subjects with skeletal class II and division 2 malocclusion, taken at the pre-treatment (T1) and post-leveling and alignment (T2) phases, were analyzed. All these patients were treated with non-extraction methods in the initial stage. A total of 25 skeletal and dental parameters, which included linear and angular measurements, were evaluated. Statistical analysis A paired t-test was used to compare the difference in the dimensional values between (T1) and (T2) points of the time period. The results were considered statistically significant at Bonferroni adjusted p<0.002. Results A statistically significant positional change was noted in the condylar position both in the vertical and sagittal directions, resulting in sagittal changes of the mandible in the forward direction. The deep bite was relieved by vertical changes in the dental structures in both the posterior and anterior segments. Growth changes in the vertical direction were also noted but not conclusive. Conclusions There was a definite horizontal shift of the mandible, improving maxillo-mandibular relations following the unlocking of the bite in class II division 2 patients. This shift is mostly attributed to the condylar repositioning in the forward and downward directions.

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AIM: This study sought to correct the assessment of orthodontic camouflage treatment to provide a harmonized soft-tissue profile, consistent occlusion, and a pleasant smile. BACKGROUND: Class-II, division 2 malocclusions can be treated through dental compensation and growth modification methods instead of surgical-orthodontic treatment, which can be determined by the growth and age of the patient. CASE DESCRIPTION: This case report was of a 14-year-old Chinese female whose chief complaint was crowding of anterior teeth and required treatment for the same. On necessary clinical and radiographical examination, diagnosis of convex facial profile with class-II, division 2 malocclusion was arrived and hence treated with orthodontic camouflage. On treatment completion of 33 months, cephalometric assessment revealed that the anterior maxillary teeth had been successfully intruded and substantially distalized, with a slight counterclockwise rotation of the mandible. The treatment results and profile changes were demonstrated with good patient cooperation. CONCLUSION: Using a utility arch with orthodontic camouflage treatment can help to reinforce molar anchoring and improve a deep bite in the maxillary dentitions. The patient was treated with the devised treatment plan and acceptable results were obtained with patient satisfaction as recorded after 1 year of follow-up. CLINICAL SIGNIFICANCE: To correct a maxillomandibular discrepancy, an orthodontist may conduct a process known as camouflage therapy without necessity of surgery. However, patient selection forms a crucial role, and hence systematic arrival of the diagnosis and treatment protocol is a pivotal factor.

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BACKGROUND: Since there is no comparison between the effects of Sabbagh Universal Spring 2 (SUS2) appliance on Class II division 1 (div 1) versus Class II division 2 (div 2) patients, this preliminary study was conducted to comparatively assess, for the first time, the effects of SUS2 on 34 cephalometric indices in Class II/1 versus Class II/2 patients. MATERIALS AND METHODS: This before-after clinical trial was conducted on 75 observations of 25 patients with Class II malocclusion, of whom 12 (9 females and 3 males) had Class II div 1 and 13 (11 females and 2 males) had Class II div 2 malocclusion diagnosed by clinical examination and cephalometric assessment. The growth level of all patients had to be CS3 according to the cervical vertebral maturation index. Lateral cephalographs were obtained before treatment (T0) and the patients underwent fixed orthodontic treatment. Lateral cephalographs were taken again (T1) and the patients received SUS2 functional appliance for 6 months. A final lateral cephalograph (T2) was then obtained. Thirty-four dentoskeletal indices were measured on lateral cephalographs, and changes in indices over time were determined and compared using repeated-measures analysis of variance, post hoc test, and t-test (α =0.05). RESULTS: Within-group comparisons showed significant changes over time in SNB, sella nasion (SN)/occlusal plane, ANB, articular (Ar)-pogonion (Pog), L1-NB, condylion (Co)-gnathion, S-Ar/Ar-G, B-RL1, L1/nasion-point B (NB), U6-RL2, incisor mandibular plane angle, overjet, overbite, U1-RL1, and L1-RL2 (P < 0.05). The two groups were significantly different in terms of changes occurred to overjet, interincisal angle, U1/RL1, L1-NB, U1-NA, U1/NA, the Jarabak ratio, A-RL1, U1/SN, Pog-NB, and Co-A (P < 0.05). CONCLUSION: The SUS2 showed therapeutic efficacy for both Class II div 1 and 2 patients although it more commonly caused dentoalveolar rather than skeletal changes. Our study showed no considerable difference between the two groups after using this appliance, and the difference in the Jarabak ratio indicated better long-term growth pattern of div 2 patients and its conformity with camouflage treatments (mild or moderate Class II).

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Class II malocclusions are one of the most commonly encountered problems in orthodontics. A class II division 2 type of malocclusions is one in which there is distocclusion of the molars along with retroclined central incisors. These occur but quite rarely in the practice and not many varieties of treatment modalities have been published in the recent literature. The use of protraction and retraction utility arch has been advocated in the following case along with fixed orthodontic treatment in a prepubertal male child to obtain stable results. HOW TO CITE THIS ARTICLE: Kannan S, Saravanan S, Arora N, et al. Treatment of Class II Division 2 Pattern malocclusion Using Protraction Utility Arch in a Prepubertal Patient: A Clinical Case Report. Int J Clin Pediatr Dent 2020;13(4):416-420.

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INTRODUCTION: The collum angle that defines the crown root angulation of the single rooted teeth plays an important in treatment planning. OBJECTIVE: To compare the collum angle (crown root angulation) of maxillary and mandibular anterior teeth in different skeletal malocclusions using Cone Beam Computed Tomography (CBCT). MATERIALS AND METHODS: Sixty subjects were categorized into four groups (fifteen subjects in each group) Class I, Class II division 1, Class II division 2 malocclusion and Class III based on Angle classification, Wits and ANB. The collum angle of maxillary and mandibular anterior teeth was measured using CBCT. One way ANOVA, Post hoc comparison with Tukey HSD and Paired t-test were used to analyse the measured data. RESULTS: The collum angle of corresponding right and left side teeth were averaged. Thus, the mean and standard deviation of the collum angle (n-30) were generated for maxillary and mandibular central incisors, lateral incisors, and canines. A statistically significant increase was observed in the maxillary central incisors of Class II division 2 and mandibular lateral incisors of class III malocclusion. The collum angle was increased in mandibular canines of Class III malocclusion when compared with class I and Class II division 2 malocclusion. The collum angle was negative in mandibular central incisors of Class II division 2. No statistically significant difference was observed in the mean collum angle between the right and left side anterior teeth in all the four groups. CONCLUSION: A variation in Collum angle was observed between the maxillary and mandibular anterior teeth and malocclusions. The effect of these variations in collum angle in torque expression and biomechanics should be kept in mind by the orthodontist before treatment planning especially in Class II division 2 malocclusion.

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PURPOSE: The aim of this study was to compare the mandibular posterior space in subjects with skeletal class II division 1 and division 2 malocclusions in two different age groups. METHODS: Pretreatment cephalometric radiographs of 160 patients from 9 to 13 years of age (n = 80) and 15 to 18 years of age (n = 80) with class II division 1 or division 2 malocclusion were used for the study. Equal numbers of male and female patients (n = 20) were included in the two age groups in each of the malocclusion groups. Eight linear and six angular measurements were taken for mandibular posterior space evaluation. The data obtained from the study were compared using the independent t-test. RESULTS: In the present study, the mandibular posterior space was greater in both malocclusion groups in subjects aged 15-18 years than in those aged 9-13 years (p < 0.05). The available posterior spaces behind the mandibular first molars were 4.4 mm and 6.3 mm in females (class II divisions 1 and 2, respectively) and 5.3 mm and 7 mm in males (class II divisions 1 and 2, respectively) in the 9­ to 13-year-old age group. This space increased significantly by 6.9 mm (p < 0.001) and 3.2 mm (p < 0.01) in females (class II division 1 and 2, respectively) and 3.8 mm (p < 0.01) and 3 mm (p < 0.01) in males (class II division 1 and 2, respectively) in the 15- to 18-year-old age group. CONCLUSION: Class II division 1 and division 2 malocclusions had similar and inadequate posterior space dimensions for the eruption of the third and an unknown portion of the second molars.

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