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OBJECTIVES@#To evaluate the effects of a Twin-block appliance on the condyles of patients with ClassⅡmalocclusion by conducting a systematic review and a Meta-analysis.@*METHODS@#Pubmed, Embase, Cochrane Library, Chinese BioMedical Literature Database, China National Knowledge Infrastructure, and VIP Database were electronically searched. Randomized controlled trials, controlled clinical trials, and single-arm trials on condylar changes produced by a Twin-block appliance in patients with ClassⅡmalocclusion were included. Two reviewers independently extracted and assessed the risk of bias. Meta-analyses were conducted with Review Manager 5.3.@*RESULTS@#Eight studies were included; among which, seven were of high quality. After treatment with a twin block appliance, condyles moved anteriorly. The anterior joint spaces decreased (P<0.000 01), whereas the posterior spaces increased (P<0.000 01). The superior spaces were not changed (P=0.11). Moreover, a significant difference was observed in the increase of the condylar space index (P<0.000 01). After treatment, the anteroposterior diameters of the condyles and condylar height increased (P=0.000 2 and P<0.000 01, respectively). By contrast, no significant changes were discovered in the medial external diameters of the condyles (P=0.42).@*CONCLUSIONS@#A Twin-block appliance can promote the growth of a condyle in the posterior and upper direction and move it forward in favor of the correction of Class Ⅱ malocclusion.
Subject(s)
Humans , Malocclusion, Angle Class II/therapy , Temporomandibular Joint , Bone and Bones , China , Orthodontic Appliances, Functional , CephalometryABSTRACT
@#A 9-year-old male ADHD patient with class II dentoskeletal malocclusion came to the Pediatric Department of Universitas Airlangga, Surabaya, with a chief complaint of a protrusive look. The patient had a behavior disorder of ADHD (Attention Deficit Hyperactivity Disorder), in which its symptoms may be challenging in dental treatment since it heavily depends on the patient’s obedience and case selection. References and similar studies of myofunctional therapy in Class II Malocclusion Patients with ADHD are still scarce. Most patients with class II malocclusion present with hyperactive perioral muscle and altered tongue position. Hence, myofunctional appliance is a reliable treatment choice. A special rule where the patient was asked to focus on the operator’s instruction for 10 minutes and then a 5-minute break, was applied to this patient to overcome ADHD symptoms as a behavior management strategy. This is in line with a theory stating that children with ADHD are prone to distraction, causing them to have a shorter duration of focus, limited sustained attention span, poor impulse control, and motor overactivity compared to normal children. This strategy gave a positive result in maintaining the cooperation of the patient using the twin block for 6 months which is lead to positive progress in malocclusion correction.
Subject(s)
Attention Deficit Disorder with Hyperactivity , Myofunctional TherapyABSTRACT
ABSTRACT@#Functional appliances have been used over a century in clinical orthodontic treatments for skeletal Class II malocclusion patients. Its popularity is attributed to its high patient adaptability and ability to produce rapid treatment changes. The twin block and lip bumper can be combined depending on the patient’s cases. The purpose of therapy with twin block is effective in mandibular growth deficiencies to induce supplementary lengthening of mandibular by stimulating increased growth at the condylar cartilage. The patient was a ten-year-old male patient with skeletal Class II malocclusion. He had a convex facial profile, SNA (sella, nasion, A point) angle of 77.5°, SNB (sella, nasion, B point) angle of 73.0°, ANB (A point, nasion, B point) angle of 4.5°, overjet of 6.5 mm, overbite of 11/41 = 5.0 mm, 21/31 = 4.5 mm, abnormal upper labial frenulum, crossbite in the second left premolar of maxilla, crowded anterior teeth of mandibular, deficiency of mandibular growth, lower lip sucking habit, anterior teeth of maxilla with diastema and proclination. Orthodontic treatment for patient is a combination of twin block and lip bumper appliances. After seven months, frenectomy is used to eliminate and correct the spacing in the frenulum. After 10 months, the patient’s skeletal and profile had improved to skeletal Class I malocclusion, SNA angle of 78.0°, SNB angle of 75.0°, ANB angle of 3.0°, overbite and overjet of 4.0 mm, and the lower lip sucking habit had stopped. Twin block and lip bumper appliances are particularly good alternative treatment in managing selected cases of skeletal Class II malocclusion.
Subject(s)
Malocclusion, Angle Class IIABSTRACT
@#Introduction: A parallel design randomized clinical trial was conducted to compare dentoalveolar and skeletal changes in two groups of patients who had completed twin block therapy; one group had a three-month night-time retention period whereas the other group had no retention period, after twin block therapy but before fixed appliances. Methods: 26 participants of Malay ethnicity aged 10 to 15 years were included in the trial and had an overjet of 5mm or greater, molar relationship greater than half cusp Class II on a skeletal Class II base which had been corrected to a Class I molar relationship following twin block therapy. Following randomization, the 26 were divided into two groups of 13. Group A had fixed appliances bonded immediately whereas group B continued wearing twin block at night for three months, after which fixed appliances were bonded. Lateral cephalograms assessed were those taken before randomization, upon twin block therapy completion (T1) and six months after bond-up of fixed appliances (T2). Results: Paired t-test showed several statistically significant dentoalveolar and skeletal changes in group A. In contrast, only condylar head position exhibited a statistically significant change in group B. Despite a statistical significance, changes measured in both groups were minimal at less than 2mm and therefore clinically insignificant. Independent t-test showed no statistically significant difference between the changes recorded in both groups. Conclusion: The results suggest that a three-month night-time retention period after twin block therapy does not lead to any changes that may be considered clinically beneficial.
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@#Introduction: The aim of the study was to compare the changes in the skeletal and dentoalveolar structures in Malay patients with Class II Division 1 malocclusion treated by prefabricated re-mouldable customizable functional appliance (T4FTM) and Twin Block (TB) appliance. Methods: A randomised clinical trial was carried out with samples randomly assigned to active (TB appliance) and experimental (T4FTM appliance) groups. Pre- and post-treatment lateral cephalometric radiographs were taken for each subject and the overjet was clinically measured at the same intervals. 20 angular and linear measurements were chosen and measured separately. Results: Independent t test was used to compare the changes between the two groups. A significant difference between the groups was seen with overjet at 2.14 mm (p < 0.01), Sv_Pog distance at 1.83mm (p < 0.05), Sv_ii distance at 2.55 mm (p < 0.001), horizontal distance from the upper to the lower incisor tip at 1.81 mm which was statistically significant (p < 0.05). The other variables SNB and ANB angles too showed a significant difference. However, all the favourable changes were noted in the TB group. Conclusion: T4FTM appliance could be an effective appliance for the management of British Standard Institute's Class II Division 1 malocclusion on Class II skeletal pattern. However, the TB group differed significantly and had a more favourable correction in terms of the sagittal skeletal and dentoalveolar discrepancy.
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Twin Block appliances are largely used for the correction of skeletal class II malocclusions due to mandibular retrognathism. Due to its patient comfort and ease, this appliance became the major tool for class II skeletal correction. Literature review on this appliance shows mixed responses, some claiming that the results are good and stable while others just put this as an appliance giving temporal acceleration in growth. Hence a study was designed to investigate the stability attained in antero posterior skeletal correction attained with Twin Block appliance. 30 subjects who were treated for mandibular retrognathism were identified. Average age group was 12.9[T1], 14.8 [T2] and 16.5 years [T3]. Pre-treatment, post treatment and a minimum of one year post treatment cephalograms were collected and analyzed. Results obtained from the present study showed that the treatment outcomes that were achieved immediately after twin block therapy was stable and that twin block appliance could be recommended in patients with sufficient growth with mandibular retrognathism.
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Objective: To detect the clinical effect of T win-Block appliance in the treatment of the patients with Class II division 1 malocclusion, and to provide the basis for clinical treatment. Methods: A total of 30 patients with class II division 1 malocclusion were treated with Twin-Block appliance. The variables of the patients before and after treatment were measured with Ricketts cephalometric radiographys. Results: Compared with before treatment, the length of corpora mandibulae (Xi-Pm) of the patients after treatment was increased by 2. 50 mm (P<0. 05), the SNB angle was increased by 2. 58° (P<0. 05), and the ANB was decreased by 2. 71 (P<0. 01); the molar relationship distance and the Overjet were decreased by 2. 81 mm and 3. 68 mm, respectively (P<0. 01); the Ll-OP was decreased by 1.89 mm, the distance of Ll-APog was increased by 1.84 mm, and the angle Ul-APog was decreased by 7. 35° (P<0. 01); the Ls-TVL was increased by 1. 85 mm, the Sm-TVL was increased by 2. 12 mm (P<0. 05), and the Pos-TVL was increased by 2. 89 mm (P<0. 05). Conclusion: The Twin-Block appliance could obviously promote the development of mandibular bone, upright the anterior teeth and improve the lip angle of upper anterior teeth and the proflie in the treatment of the patients with class II division 1 malocclusion in the growth development period.
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Objective: To observe the clinical effects of upper articular cavity injection with hyaluronate(HA) combined with Twinblock in the treatment of temporomandibular joint(TMJ) clicks. Methods: 60 patients with TMJ clicks were divided into 3 groups(n = 20) and were treated by articular cavity injection combined with Twin-block(group 1),Twin-block only(group 2) and injection of sodium hyaluronate gel(group 3) respectively. The effects were evaluated and compared before and after treatment by both doctors and patients. Results: The effective rate of group 1,2 and 3 was 95％,and 65％ respectively(P ＜ 0. 05). After treatment the TMJ clicks were almost dispeared in group 1,remitted in group 2 and slightly remitted in group 3. Conclusion: The articular cavity injection of HA combined with Twin-block is more effective in the treatment of TMJ clicks than Twin-block or articular cavity injection of HA.
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Objective@# To investigate the morphology and position changes of displaced disk with reduction after treatment by modified Twin-block. @*Methods @#19 patients were diagnosed as displaced disk with reduction and they were treated with modified Twin-block from July 2015 to June 2016. 28 temporomandibular joints (TMJ) of these patients were included in the analysis. The disk length, disk-condylar distance, and disk-condylar angle were measured with MRI before and after treatment. Paired t-test was used. Disk morphology before and after treatment was also documented and analyzed by Wilcoxon signed rank test. The statistical significance was set at P<0.01.@*Results @# 28 TMJ disks were anteriorly displaced with reduction. 24 of them were repositioned while the other 4 were still anteriorly positioned after treatment. The disk length was increased significantly (P<0.01) while the disk-condylar distance and disk-condylar angle were decreased significantly after treatment (P<0.01). The disk morphology as hemiconvex (16) and bi planar (9) were the majority before treatment, while biconcave (16) and biplanar (10) were changed to the larger part after treatment. There was improvement on the disk deformation with a statistical significance (P<0.01). Larger disk-condylar distance, disk-condylar angle and severer deformation of disks were observed in the 4 disks without reposition.@*Conclusion @# Modified twin-block is an effective appliance for disk displacement with reduction by repositioning the disk and modifying the disk deformation. However the effect is not good for disks with severer deformation and displacement. Further studies with larger sample and stratified group are still needed.
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ABSTRACT Objectives: To evaluate the cephalometric changes in skeletal, dentoalveolar and soft tissue variables induced by Clark's Twin Block (CTB) in Class II, Division 1 malocclusion patients and to compare these changes in different cervical vertebral maturation stages. Methods: Pre- and post-treatment/observation lateral cephalograms of 53 Class II, Division 1 malocclusion patients and 60 controls were compared to evaluate skeletal, dentoalveolar and soft tissue changes. Skeletal maturity was assessed according to cervical vertebral maturation stages. Pre- and post-treatment/observation mean changes and differences (T2-T1) were compared by means of Wilcoxon sign rank and Mann-Whitney U-tests, respectively. Intergroup comparisons between different cervical stages were performed by means of Kruskal-Wallis test and Mann-Whitney U-test (p ≤ 0.05) . Results: When compared with controls, there was a significant reduction in ANB angle (p < 0.001), which was due to a change in SNB angle in CS-2 and CS-3 (p < 0.001), and in SNA (p < 0.001) and SNB (p = 0.016) angles in the CS-4 group. There was significant increase in the GoGn-SN angle in CS-2 (p = 0.007) and CS-4 (p = 0.024), and increase in Co-Gn and Go-Gn amongst all cervical stages (p < 0.05). There was significant decrease in U1-SN and increase in IMPA amongst all cervical stages (p < 0.05). There was significant retraction of the upper lip in CS-3 (p = 0.001), protrusion of the lower lip in CS-2 (p = 0.005), increase in nasolabial angle in CS-4 (p = 0.006) and Z-angle in CS-3 (p = 0.016), reduction in H-angle in CS-2 (p = 0.013) and CS-3 (p = 0.002) groups. When pre- and post-treatment mean differences were compared between different cervical stages, significant differences were found for SNA, SNB and UI-SN angles and overjet. . Conclusions: The Twin-Block along with the normal craniofacial growth improves facial esthetics in Class II, Division 1 malocclusion by changes in underlying skeletal and dentoalveolar structures. The favorable mandibular growth occurs during any of the cervical vertebral maturation stages, with more pronounced effect during CS-3 stage.
RESUMO Objetivo: avaliar as alterações em variáveis cefalométricas esqueléticas, dentoalveolares e do perfil tegumentar, induzidas pelo aparelho Twin Block de Clark (TBC), em pacientes com má oclusão de Classe II, divisão 1, e comparar as alterações nos diferentes estágios de maturação das vértebras cervicais. Métodos: telerradiografias laterais pré- e pós-tratamento de 53 pacientes com má oclusão de Classe II, divisão 1, foram comparadas às telerradiografias de 60 pacientes controle, para avaliar as alterações esqueléticas, dentoalveolares e no perfil tegumentar. A maturação esquelética foi avaliada de acordo com os estágios de maturação das vértebras cervicais. As alterações médias e as diferenças entre o pré- e o pós-tratamento (T2 - T1) foram comparadas por meio do teste de postos sinalizados de Wilcoxon e do teste U de Mann-Whitney, respectivamente. Foram realizadas comparações intergrupos para os diferentes estágios de maturação das vértebras cervicais, por meio do teste de Kruskal-Wallis e teste U de Mann-Whitney (p ≤ 0,05). Resultados: em comparação aos pacientes do grupo controle, constatou-se que houve uma redução significativa do ângulo ANB (p < 0,001), em virtude de alterações no ângulo SNB nos estágios CS2 e CS3 (p < 0,001), e nos ângulos SNA (p < 0,001) e SNB (p = 0,016) no estágio CS4. Houve um aumento significativo do ângulo GoGn-SN nos estágios CS2 (p = 0,007) e CS4 (p = 0,024), e um aumento em Co-Gn e Go-Gn em todos os estágios de maturação das vértebras cervicais (p < 0,05). Houve redução significativa em U1-SN e um aumento do IMPA em todos os estágios de maturação das vértebras cervicais (p < 0,05). Houve retração significativa do lábio superior em CS3 (p = 0,001), protrusão do lábio inferior em CS2 (p = 0,005), aumento do ângulo nasolabial em CS4 (p = 0,006) e do ângulo Z em CS3 (p = 0,016), além de redução do ângulo H em CS2 (p = 0,013) e CS3 (p = 0,002). Quando as diferenças médias entre pré- e pós-tratamento foram comparadas entre os diferentes estágios de maturação das vértebras cervicais, foram identificadas diferenças significativas para os ângulos SNA, SNB e UI-SN, assim como para o overjet. Conclusões: o uso do aparelho Twin-Block, associado ao crescimento craniofacial normal, melhora a estética facial em pacientes com má oclusão de Classe II, divisão 1, por meio de alterações nas estruturas esqueléticas e dentoalveolares subjacentes. Esse crescimento mandibular mais favorável pode ocorrer durante qualquer um dos estágios de maturação das vértebras cervicais, com um efeito mais acentuado durante o estágio CS3.
Subject(s)
Humans , Male , Female , Adolescent , Cervical Vertebrae/growth & development , Cephalometry , Orthodontic Appliances, Functional , Malocclusion, Angle Class II/therapy , Mandible/growth & development , Nose/anatomy & histology , Esthetics, Dental , Lip/anatomy & histologyABSTRACT
Abstract Introduction: Narrow airway dimensions due to mandibular deficiency can predispose an individual to severe respiratory distress. Hence, treatment with mandibular advancement devices at an early age might help improving the pharyngeal passage and reduce the risk of respiratory difficulties. Therefore, the aim of the current study was to evaluate the mean changes in the pharyngeal dimensions of children with mandibular deficiency treated with Clark's twin-block appliance (CTB) followed by fixed orthodontic treatment. Methods: Orthodontic records of 42 children with mandibular deficiency were selected. Records comprised three lateral cephalograms taken at the start of CTB treatment, after CTB removal and at the end of fixed appliance treatment, and were compared with 32 controls from the Bolton-Brush study. Friedman test was used to compare pre-treatment, mid-treatment and post-treatment pharyngeal dimensions. Wilcoxon signed rank test was used to compare the airway between pre-treatment and post follow-up controls. Mann-Whitney U test was applied to compare the mean changes in pharyngeal dimensions between treatment group and controls from T2 to T0. Post-hoc Dunnet T3 test was used for multiple comparisons of treatment outcomes after CTB and fixed appliances, taking a p-value of ≤ 0.05 as statistically significant. Results: Superior pharyngeal space (p < 0.001) and upper airway thickness (p = 0.035) were significantly increased after CTB, and the change in superior pharyngeal space remained stable after fixed mechano-therapy. Conclusion: CTB can have a positive effect in improving pharyngeal space and the resultant increase in airway remains stable on an average of two and a half years.
Resumo Introdução: a redução nas dimensões das vias aéreas causada pela deficiência mandibular pode predispor um indivíduo a dificuldades respiratórias severas. Assim, o tratamento com aparelhos de avanço mandibular na infância pode contribuir para melhorar a via aérea faríngea e reduzir o risco de problemas respiratórios. Objetivo: o objetivo do presente estudo foi avaliar as alterações médias nas dimensões da faringe de crianças com deficiência mandibular tratada com o aparelho Twin Block (TBC) seguido pelo tratamento ortodôntico fixo. Métodos: a documentação ortodôntica de 42 crianças com deficiência mandibular, consistindo de três telerradiografias de perfil - tiradas ao início do tratamento com TBC (T0), após a remoção do aparelho (T1) e ao final do tratamento ortodôntico fixo (T2) - foi selecionada e comparada à de 32 crianças controle do estudo Bolton-Brush. O teste de Friedman foi utilizado para comparar as dimensões da faringe antes, durante e após o tratamento. O teste de postos de Wilcoxon foi utilizado para comparar as vias aéreas antes do tratamento e depois do acompanhamento das crianças controle. O teste U de Mann-Whitney foi empregado para comparar as alterações médias nas dimensões da faringe entre o grupo tratado e as crianças controle, de T0 a T2. O teste T3 de Dunnett foi utilizado como post-hocpara realizar comparações múltiplas dos resultados do tratamento após o uso do TBC e dos aparelhos fixos, considerando-se como estatisticamente significativo um valor de p ≤ 0,05. Resultados: o espaço faríngeo superior (p < 0,001) e a espessura das vias aéreas superiores (p = 0,035) aumentaram significativamente após o uso do TBC, e a alteração no espaço faríngeo superior permaneceu estável após a mecanoterapia fixa. Conclusão: o TBC pode produzir um efeito positivo no espaço faríngeo, e aumento resultante nas vias aéreas permanece estável, em média, por dois anos e meio.
Subject(s)
Humans , Child , Pharynx , Cephalometry , Orthodontic Appliances, Functional , Malocclusion, Angle Class II/therapy , MandibleABSTRACT
Myofunctional appliances become active through muscular forces that bring about the dentoalveolar and skeletal changes. Functional appliances can be both removable or fixed. Twin block appliance given by William Clark is one of the most popular functional appliance owing to its ease of fabrication for the orthodontist and its ease of wear for the patient. It is known to bring about both skeletal and dental changes and has been used extensively in Class II growing patients. This was a case report of a 12-year-old patient treated in two phases, first the functional phase using the twin block, followed by the second phase of fixed orthodontic appliance.
Subject(s)
Child , Female , Humans , Malocclusion, Angle Class II/epidemiology , Malocclusion, Angle Class II/therapy , Orthodontic Appliance Design , Orthodontic Appliances, Functional , Orthodontics, Corrective/instrumentation , Orthodontics, Corrective/methodsABSTRACT
Objective:To assess the effect and mechanism of ClassⅢ malocclusions treatment with Frankel-Ⅲ appliance and reverse Twin-block appliance. Methods:Twenty subjects of ClassⅢ malocclusion were included in this study(9 males,11 females). Among them, 10 subjects were randomly selected for treatment with reverse Twin-block appliance (T group) and 10 subjects for Frankel-Ⅲ appliance (F group). All patients were treated all the day for total of 4-11 months. The cephalometric records of these subjects were examined before and after treatment. The acquired data were processed with SPSS 10.0. Results: The results showed a mandible receded backward in both groups. Both group could accelerate the development of the maxillary bone. But the Frankel-Ⅲ was more effective. F group had significant effects of uprighting upper frontal teeth and flaring lower teeth. the average treatment time was 6.5 months in reverse twin-block appliance therapy group and 9 months in Frankel-Ⅲ appliance group. Conclusion: Both reverse Twin-block appliance and Frankel-Ⅲ appliance can treat angle classⅢ malocclusions effectively. The effects of maxillary changes of Frankel-Ⅲ appliance is better than reverse Twin-Block. Treatment period is shorter in T group than in F group.
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Objective; To evaluate the efficacy of Twin-block appliance in Class Ⅱ division 1 of adolescents. Methods: Several e-lectronic databases (PubMed, The Cochrane library, Embase, CBMdisk, CNKI, VIP)were searched. Abstract that appears to fulfill the initial selection criteria were selected by consensus and original articles were retrieved. Five Chinese journals were hand searched for possible missing articles. Randomized controlled trials(RCTs) that evaluate the efficacy of Twin-block appliance in Class Ⅱ division I adolescents without any surgical intervention or syndromic characteristics were considered. A comparable untreated control group was required to factor out normal growth changes. The quality of included studies was evaluated according to Cochrane Reviewers Handbook 4.2.6 Meta-analysis was performed by using RevMan 5.0.0 software. Results: Four RCTs including 289 patients were identified. The results of our meta-analysis showed a significant increase on SNB angle, Ar-Gn, Nasolabial angle and Labial-mental fold compared with control group(P<0.05). Whereas overjet, overbite, ANB angle and Ls-E had a significant decrease. In addition, SNA angle and Li-E didnt show statistical significant changes(P>0. 05). Conclusion; In Class II division 1 of adolescents, Twin-block appliance can effectively decrease their overjet, overbite, ANB angle, and induce anterior-posterior growth of mandible. The effect on restrain forward growth of the maxilla was unclear. More RCTs are required to evaluate the efficacy of Twin-block appliance.
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Objective To evaluate the curative effects of the modified fixed reverse Twin-block ap-pliance (TBA)combined Edgewise in the treatment of adult Angle Ⅲ anterior crossbite. Methods The appliance was used in 18 subjects with adult Angle Ⅲ skeletal malocclusion and clinical characters and X-ray cephalometry were then compared before and after treatment. Results The mandibular soft tissue changes could be achieved fast and the profile had changed effectively. Moderate labioclination of maxil-lary anterior teeth played a role in the improvement of axillary soft tissue protrusion. The cases were fol-lowed up as long as 3 years. No relapse occurred in all the patients. Anterior occlusion was normal. Con-clusion All findings indicate that adult Angle Ⅲ anterior crossbite can be quickly corrected with the mod-ified fixed reverse TBA combined Edgewise. The effect on mandibular soft tissue is significant.
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O paciente Padrão II de morfologia facial portador de maloclusão Classe II, possui características clínicas específicas, as quais são vistas pela interação entre os tecidos mole e ósseo, o retrognatismo mandibular é uma delas, expressado na morfologia da face. O tratamento da maloclusão Classe II foi e tem sido pesquisado na Ortodontia e Ortopedia Funcional dos Maxilares. É de suma importância recursos que auxiliem nas diretrizes do crescimento e desenvolvimento crânio facial em busca de devolver o equilíbrio entre as bases ósseas, quando essas sofreram alguma alteração entre a forma e função. Este estudo teve como finalidade avaliar o tratamento em pacientes portadores de maloclusão Classe II, com retrusão mandibular em fase de crescimento com o aparelho Twin-Block. A amostra foi composta de 14 pacientes, sendo sete do gênero feminino e sete do gênero masculino com média de idade de 12 anos e 1 mês. Foram analisadas em telerradiografias cefalométricas as seguintes medidas: SNB, comprimento mandibular (Xi-Pog), profundidade facial (PF), altura facial anterior inferior (AFAI), comprimento do corpo mandibular (Go-Gn), comprimento do ramo (Co-Go). O tratamento foi realizado por um período médio de 12 meses e foram encontrados os seguintes resultados. Por meio desta pesquisa pode-se concluir que o aparelho Twin-block , possibilitou um bom manejo no crescimento mandibular, através do deslocamento da mandíbula, pelo aumento do comprimento mandiibular e altura facial anterior inferior da face. Melhorando a harmonia entre as bases ósseas e tecido tegumentar.
The patient who has malocclusion of type Class II Pattern II shows specific clinical characteristics that when interact with the indolent tissue and bone can promote an antero-posterior unbalance between the bone basis, the tendency to the retrognathism in the mandible is one of them, which can get a certain degree of aesthetical and functional discomfort. This study has had the aim to study the conditions of mandible growth and possible alterations teeth-skeleton by the use of the apparatus Twin-block in patients with maloclusão Class II, division 1st, with mandible regression in a growth level. It was analyzed cefalométricas radiographies in lateral part of the head from one sample compounded by 14 patients; seven are from women and seven from men about 12 years old and 1 month and analyzed the following cefalometric measures: SNB, mandible length (Ricketts), facial depth, AFAI, mandible length (USP), length of the section (USP). The apparatus was installed for a medium period of time of 12 months. Through the collected data in this research we might conclude that. The Twin-block has shown as a functional orthopedic apparatus used to correction of important skeletal differences between the jaw and the mandible, improving the harmony between the bases
Subject(s)
Humans , Male , Female , Adolescent , Malocclusion, Angle Class II , Mandibular Advancement , Orthodontic Appliances, Functional , OrthodonticsABSTRACT
O objetivo deste estudo foi avaliar as alterações dento-esqueletais decorrentes do uso do aparelho funcional Twin Block e do aparelho extra-oral de Thurow, em pacientes portadores de maloclusão de Classe II, tratados na fase de pré-surto de crescimento puberal, durante o período de doze meses. Cinqüenta e oito pacientes foram selecionados aleatoriamente segundo critérios de inclusão para compor a amostra. Dezenove pacientes utilizaram o aparelho funcional, dezenove o aparelho extra-oral de Thurow e o restante compuseram o grupo Controle. Foram analisadas radiografias cefalométricas ao início e ao final de doze meses de acompanhamento. Os valores cefalométricos obtidos foram tratados estatisticamente (ANOVA), seguindo um agrupamento de medidas para análise das modificações das estruturas dento-esqueletais. O teste de Bonferroni foi utilizado para a comparação dos pares de grupos. Os resultados sugerem que o aparelho funcional Twin Block promoveu aumento significativo (p < 0,001) no comprimento total da mandíbula, redução na relação ântero-posterior maxilo-mandibular e aumento da altura facial inferior quando comparado ao grupo Controle. Ocorreu redução significativa (p < 0,001) da inclinação dos incisivos superiores em ambos os grupos. Quanto à projeção dos incisivos superiores o grupo Twin Block promoveu redução significativa (p < 0,001), enquanto o aparelho de Thurow apresentou aumento significativo (p < 0,001). Os incisivos inferiores, quanto à angulação, mostraram significativa redução no grupo Thurow. A demais medidas avaliadas não mostraram alteração estatisticamente significativa.
The aim of this study was to evaluate dento skeletal changes due to Twin-Block and to Thurow appliances use in class II malocclusion patients, treated during pre growing spur phase for 12 months. Sample was composed by 58 randomly selected patients, following inclusion criteria. Nineteen patients used Twin-Block appliance, 19 were submitted to Thurow ones and the rest belonged to control group. Cephalometrics were done in the beggining and by 12 months of treatment. Data obtained from cephalometry was statistically analyzed, as measurements were divided into groups for dental and skeletal structural changes to be evaluated. Bonferroni test was used for paired groups comparation. Results suggest the Twin Block functional appliance promotes statistically significant changes (p < 0,001) as regard to total mandible length, a maxilo-mandibular antero-posterior reduction and anterior facial length increasing when compared to control group. Significant reduction (p < 0,001) of upper incisors inclination and significant increasing (p < 0,001) in lower incisors proclination for Thurow group when compared to control group may also be considered. Maxillary growth restriction, maxillary distalization nor first molars antero-posterior position changes were observed.
Subject(s)
Humans , Child , Mandibular Advancement/instrumentation , Mandibular Advancement/methods , Malocclusion, Angle Class II , Malocclusion, Angle Class II/therapy , Orthodontic Appliances , Orthodontic Appliances, Functional , Analysis of Variance , Cephalometry/methods , Image Processing, Computer-AssistedABSTRACT
Objective: To evaluate the effects of the modified fixed r everse Twin-block appliance(TBA) combined with maxillary protraction appliance( MPA) in the treatment of early Angle Ⅲ skeletal anterior crossbite. Met hods:TBA combined with MPA was used in 15 growing subjects with early An gle Ⅲskeletal malocclusion (group TBA-MPA). Another 15 subjects with the same type of malocclusion were treated by MPA(group MPA). The effects of treatment we re studied by cephalometric measurments.Results:3-5 months afte r treatment SNB, B-Vert T, Po-Vert T,NPo-FH,Co-Po and 1-NB in group 1 were decreased more than those in group 2 (P0.05).Conclusion:Angle Ⅲ skeletal ante rior crossbite can be corrected successfully with reverse TBA combined with maxi llary protraction appliance by mandible retrusion and maxilla forward growth.