Functional treatment of bilateral posterior crossbite improves mandibular kinematics during chewing.

OBJECTIVES: To evaluate the effects of treatment of bilateral posterior crossbite (BPXB) on mandibular kinematics by the percentage of reverse chewing cycles (RCCs) during soft and hard bolus chewing before and after the correction of the malocclusion with function-generating bite (FGB). MATERIALS AND METHODS: This prospective study included 71 subjects: 19 patients with occlusally symmetric BPXB (M = 9; F = 10; mean age 9.3 ± 2.2[yr.mo]), 32 patients with occlusally asymmetric BPXB (19 with more teeth in crossbite on the right side (right prevalent side), M = 7; F = 12; mean age 8.2 ± 1.6 [yr.mo] and 13 on the left side, M = 7; F = 6; mean age 9.6 ± 1.9 [yr.mo]) and 20 controls without malocclusion (M = 8; F = 12; mean age 10.2 ± 1.7 [yr.mo]). Masticatory patterns were recorded before (T0) and after (T1) the correction of the malocclusion with FGB, with the K7-I® kinesiograph using standardized soft and hard boluses. RESULTS: BPXB was corrected in all included patients. At T0, the percentage of RCCs in BPXB was significantly increased compared to controls (P < .0001); symmetric BPXB showed no difference in RCCs between the sides, whereas asymmetric BPXB showed significantly more RCCs on the side with more teeth in crossbite (prevalent side). After treatment with FGB (T1), the percentage of RCCs was significantly reduced in both symmetric BPXB patients (soft bolus, P = .003; hard bolus, P < .001) and asymmetric BPXB patients (prevalent side: soft and hard bolus, P < .00001; non-prevalent side: soft bolus, P = .01 and hard bolus, P = .0002). CONCLUSION: Functional correction of BPXB with FGB significantly improved mandibular kinematics during chewing.

Evaluation of mandibular motion in adolescents with skeletal class II division 1 malocclusion during mandibular advancement using clear functional aligners: a prospective study.

BACKGROUND: This study aimed to evaluate the characteristics of mandibular protrusive condylar trajectory in adolescents with skeletal Class II Division 1 malocclusion and the changes of condylar trajectory during mandibular advancement (MA) treatment using clear functional aligners. METHODS: This prospective study consisted of a cross-sectional study and a longitudinal study. In cross-sectional study, sixty-one adolescents were divided into two groups: Class I (n = 30) and Class II Division 1 (n = 31). The condylar trajectory was measured and compared using the Mann-Whitney U test. The longitudinal study was the MA treatment group using clear functional aligner and consisted of 16 participants from Class II Division 1group. The condylar trajectory was collected at three-time points: pre-treatment (T1), during MA treatment at approximately 3 months (T2, 105.6 days average), and at the end of MA treatment (T3, 237.6 days average). The changes at T1, T2, and T3, as well as the symmetry between the left and right condyles across all groups, were examined using the Wilcoxon paired test. RESULTS: A greater increase in the anteroposterior displacement and space displacement during protrusive movements was observed in the Class II Division 1 group compared with that in the Class I group, with a large difference being observed in the left and right condylar movements. The condylar anteroposterior displacement and space displacement decreased significantly at T2 and increased significantly at T3; however, no significant difference was observed between T1 and T3. A significant difference was observed between the condylar movement on the left and right sides at T1; however, no significant difference was observed at T2 and T3. CONCLUSIONS: Adolescents with Class II Division 1 malocclusion had higher protrusive capacity than those with Class I. Moreover, their left and right condylar motion was more asymmetric. The range of condyle motion decreased first and then increased during MA therapy, and the left and right condyle movement became more symmetrical, which may be the adaptive response of neuromuscular function to the changes in jaw position.

[Orthodontic treatment of adult patients with mandibular retrognathia]. / Ortodonticheskoe lechenie vzroslykh patsientov s nizhnei retrognatiei.

This article describes a case report of the patient with mandibular retrognathia, class II malocclusion, constriction and deformation of dental arches and bimaxillary protrusion. Due to the patient's refuse to undergo the orthognathic surgery, after diagnostic, it was decided to carry out the orthodontic dentoalveolar compensation. The combined use of the functional fixed telescopic appliance (FFTA), bracket system and orthodontic miniscrews made it possible to effectively normalize the mandibular position, achieve orthognathic occlusion, eliminate bimaxillary protrusion and improve the face profile. This method significantly reduced invasiveness and time of orthodontic treatment.

[Algorithm for treatment of patients with class II malocclusion rejecting orthognathic surgery]. / Algoritm lecheniya patsientov s nizhnei retrognatiei, otkazavshikhsya ot kostno-rekonstruktivnoi operatsii.

The aim of this study is to develop algorithms for the treatment of patients with class II malocclusion and incisor protrusion using the combination of bracket system, functional fixed telescopic appliance (FFTA) and skeletal anchorage, which allows to achieve effective dentoalveolar compensation of skeletal forms of class II malocclusion. MATERIALS AND METHODS: Orthodontic treatment of 60 patients with class II malocclusion at the age of 18 to 44 years, using the bracket system, FFTA and orthodontic miniscrews was performed. In order to assess the results of treatment, cone-beam computed tomography were obtained at the beginning and at the end of treatment. RESULTS: As a result of the treatment normalization of lower jaw position, dental position and occlusion were achieved, the lower incisors protrusion was eliminated and the facial profile was improved, reliably confirmed by lateral cephalograms. CONCLUSION: The proposed treatment algorithm proved to be effective for stable correction of skeletal class II malocclusion in patients rejecting orthognathic surgery.

A Three-Dimensional Evaluation of Skeletal and Dentoalveolar Changes in Growing Class II Patients after Functional Appliance Therapy: A Retrospective Case-Control Study.

Background: The aim was to assess three-dimensionally mandibular and maxillary changes in growing Class II patients treated with removable functional appliances followed by fixed appliances. Methods: Twenty-four Class II patients (age range: 9 to 14, mean: 12.1 ± 1.1 years) treated with removable functional appliances followed by fixed appliances (functional appliance group-FAG) were retrospectively selected and compared to an age-matched control group (CG) treated with fixed appliances only. To be included in the study, pre- and post-treatment CBCT scans had to be available. The CBCTs were used to analyze, in 3D, the changes following treatment and growth. Results: Before treatment, overjet (FAG: 9 mm ± 2.8 (mean ± standard deviation); CG: 4 mm ± 1.7), ANB (FAG: 5.7° ± 2.0; CG: 3.2° ± 1.4), and effective mandibular length (FAG: 113.0 mm ± 4.1; CG: 116.6 mm ± 5.9) were statistically significantly different between the two groups. After treatment, overjet (FAG: -6.8 mm ± 2.8; CG: -1.8 mm ± 1.8) and effective mandibular length (FAG: 6.3 mm ± 2.6; CG: 3.9 mm ± 2.6) statistically significantly changed. There was a significant difference in the treatment effect between the FAG and the CG in overjet, ANB, and effective mandibular length. Conclusions: The results indicate that functional appliances are effective in correcting Class II malocclusions. The growth modification in the FAG resulted in an increase in mandibular length. Yet, the final length of the mandible in the FAG was smaller when compared to the CG.

Effect of Low-Level Laser Therapy on Patients With Class II Mandibular Deficiency Treated with Farmand Functional Appliance.

Introduction: Considering the positive effects of a low-level laser on new bone formation, we aimed to investigate the effects of a low-level laser in the treatment of patients with class II mandibular deficiency treated with Farmand functional appliance. Methods: Twenty-two growing patients aged 10-14 years were randomly divided into "Farmand" and "Farmand+Laser" groups. All patients were treated with Farmand functional appliance. Patients in the "Farmand+laser" group were exposed to laser irradiation (980 nm, 100 mw, 4 points around temporomandibular joints, 100 seconds each point) weekly for three months after 3-4 weeks of using the appliance. Lateral cephalometry radiographs were taken from all patients before and after the treatment period, and changes in skeletal and dental parameters were measured. Results: The association of the particular laser irradiation with the functional appliance led to a greater increase in the effective length of the mandible (Co-Gn, P=0.048), the anterior sagittal position of the mandible (SNB, P=0.029), and the length of the ramus (Co-Go, P=0.028), and it showed a further decrease in the discrepancy between the jaws (ANB, P=0.000) compared with the functional appliance alone. Conclusion: The application of the laser with the chosen parameters and protocol in conjunction with the functional appliance improved the effects of the functional appliance and reduced the discrepancy between the two jaws.

Improvement in the transverse dimension of dental arches in mixed dentition patients with posterior crossbite treated with functional therapy.

OBJECTIVES: To evaluate the effects of treatment of posterior crossbite (PXB) in the mixed dentition with the Function Generating Bite (FGB) appliance on the transverse dimension of the dental arches. MATERIALS AND METHODS: This study included 84 PXB patients (female = 46; male = 38; mean age, 8.2 ± 1.8 years) and 69 control (C) patients (female = 31; male = 38; mean age, 8.9 ± 1.4 years). Measurements were taken with digital calipers on maxillary and mandibular study casts before (T0) and after (T1) treatment for the following measures: intermolar (IMD), intermolar gingival (IMGD), intercanine (ICD), and intercanine gingival distances (ICGD). RESULTS: At T0, there was a significant difference in all maxillary measurements between the PXB and C groups (P < .001), reflecting maxillary hypoplasia in PXB patients. At T1, there was no difference between the groups. In PXB patients, the mean increase between T0 and T1 for IMD was 4.34 ± 2.42 mm; this difference measured 3.51 ± 2.19 mm for IMGD, 2.78 ± 2.37 mm for ICS, and 1.89 ± 1.7 mm for ICGD. There was no significant difference in mandibular measurements between groups at T0 and T1. CONCLUSIONS: Functional therapy with FGB is effective in significantly increasing the transverse dimension of the maxillary dental arch in PXB patients. Considering its efficacy in treating masticatory dysfunction, FGB may be considered a good treatment option for the correction of PXB in growing children.

Effectiveness of functional orthodontic appliances in obstructive sleep apnea treatment in children: literature review.

INTRODUCTION: Obstructive sleep apnea syndrome is a common condition in childhood and if left untreated can result in many health problems. An accurate diagnosis of the etiology is crucial for obstructive sleep apnea treatment success. Functional orthodontic appliances that stimulate mandibular growth by forward mandibular positioning are an alternative therapeutic option in growing patients. OBJECTIVE: To perform a literature review about the effects of functional orthodontic appliances used to correct the mandibular deficiency in obstructive sleep apnea treatment. METHODS: The literature search was conducted in June 2020 using Cochrane Library; PubMed, EBSCO (Dentistry & Oral Sciences Source), LILACS Ovid; SciELO Web of Science; EMBASE Bireme and BBO Bireme electronic databases. The search included papers published in English, until June 2020, whose methodology referred to the types and effects of functional orthopedic appliances on obstructive sleep apnea treatment in children. RESULTS: The search strategy identified thirteen articles; only four articles were randomized clinical studies. All studies using the oral appliances or functional orthopedic appliances for obstructive sleep apnea in children resulted in improvements in the apnea-hypopnea index score. The cephalometric (2D) and tomographic (3D) evaluations revealed enlargement of the upper airway and increase in the upper airspace, improving the respiratory function in the short term. CONCLUSION: Functional appliances may be an alternative treatment for obstructive sleep apnea, but it cannot be concluded that they are effective in treating pediatric obstructive sleep apnea. There are significant deficiencies in the existing evidence, mainly due to absence of control groups, small sample sizes, lack of randomization and no long-term results.

Comparison of stepwise vs single-step advancement with the Functional Mandibular Advancer in Class II division 1 treatment.

OBJECTIVE: To compare two groups of subjects at the peak of the pubertal growth period treated with the Functional Mandibular Advancer (FMA; Forestadent, Pforzheim, Germany) appliance using either single-step or stepwise mandibular advancement. MATERIALS AND METHODS: This study was conducted on 34 Class II division 1 malocclusion subjects at or just before the peak phase of pubertal growth as assessed by hand-wrist radiographs. Subjects were assigned to two groups of mandibular advancement, using matched randomization. Both groups were treated with the FMA. While the mandible was advanced to a super Class I molar relation in the single-step advancement group (SSG), patients in the stepwise mandibular advancement group (SWG) had a 4-mm initial bite advancement and subsequent 2-mm advancements at bimonthly intervals. The material consisted of lateral cephalograms taken before treatment and after 10 months of FMA treatment. Data were analyzed by means paired t-tests and an independent t-test. RESULTS: There were statistically significant changes in SNB, Pg horizontal, ANB, Co-Gn, and Co-Go measurements in both groups (P < .001); these changes were greater in the SWG with the exception of Co-Go (P < .05). While significant differences were found in U1-SN, IMPA, L6 horizontal, overjet, and overbite appraisals in each group (P < .001), these changes were comparable (P > .05). CONCLUSION: Because of the higher rates of sagittal mandibular skeletal changes, FMA using stepwise advancement of the mandible might be the appliance of choice for treating Class II division 1 malocclusions.

Effectiveness of functional orthodontic appliances in obstructive sleep apnea treatment in children: literature review / Eficácia dos aparelhos ortodônticos funcionais no tratamento da apneia obstrutiva do sono em crianças: revisão da literatura

Abstract Introduction: Obstructive sleep apnea syndrome is a common condition in childhood and if left untreated can result in many health problems. An accurate diagnosis of the etiology is crucial for obstructive sleep apnea treatment success. Functional orthodontic appliances that stimulate mandibular growth by forward mandibular positioning are an alternative therapeutic option in growing patients. Objective: To perform a literature review about the effects of functional orthodontic appliances used to correct the mandibular deficiency in obstructive sleep apnea treatment. Methods: The literature search was conducted in June 2020 using Cochrane Library; PubMed, EBSCO (Dentistry & Oral Sciences Source), LILACS Ovid; SciELO Web of Science; EMBASE Bireme and BBO Bireme electronic databases. The search included papers published in English, until June 2020, whose methodology referred to the types and effects of functional orthopedic appliances on obstructive sleep apnea treatment in children. Results: The search strategy identified thirteen articles; only four articles were randomized clinical studies. All studies using the oral appliances or functional orthopedic appliances for obstructive sleep apnea in children resulted in improvements in the apnea-hypopnea index score. The cephalometric (2D) and tomographic (3D) evaluations revealed enlargement of the upper airway and increase in the upper airspace, improving the respiratory function in the short term. Conclusion: Functional appliances may bean alternative treatment for obstructive sleep apnea, but it cannot be concluded that they are effective in treating pediatric obstructive sleep apnea. There are significant deficiencies in the existing evidence, mainly due to absence of control groups, small sample sizes, lack of randomization and no long-term results.

Resumo Introdução: A síndrome da apneia obstrutiva do sono é uma condição comum na infância e, se não tratada, pode resultar em muitos problemas de saúde. Um diagnóstico preciso da etiologia é crucial para o sucesso do tratamento dessa condição clínica. Aparelhos ortodônticos funcionais que estimulam o crescimento mandibular através do anteroposicionamento mandibular são uma opção terapêutica para pacientes em crescimento. Objetivo: Fazer uma revisão da literatura sobre os efeitos do aparelho ortodôntico funcional usado para corrigir a deficiência mandibular no tratamento da apneia obstrutiva do sono. Método: A pesquisa bibliográfica foi feita em junho de 2020 nos os bancos de dados eletrônicos da Cochrane Library; PubMed, EBSCO (Dentistry & Oral Sciences Source), Lilacs Ovid; SciELO Web of Science; Embase Bireme e BBO Bireme. A busca incluiu artigos publicados em inglês, até junho de 2020, cuja metodologia referia-se aos tipos e efeitos dos aparelhos ortopédicos funcionais no tratamento da apneia obstrutiva do sono em crianças. Resultados: A estratégia de busca identificou 19 artigos; apenas quatro eram estudos clínicos randomizados. Todos os estudos que usaram aparelhos orais ou aparelhos ortopédicos funcionais para apneia obstrutiva do sono em crianças resultaram em melhorias no índice de apneia-hipopneia. As avaliações cefalométrica (2D) e tomográfica (3D) mostraram alargamento das vias aéreas superiores e aumento do espaço das vias aéreas superiores, que melhoraram a função respiratória em curto prazo. Conclusão: Os aparelhos funcionais podem ser um tratamento opcional para apneia obstrutiva do sono, mas não é possível concluir que sejam eficazes na população pediátrica. Existem deficiências significativas nas evidências existentes, principalmente devido à ausência de grupos de controle, tamanho pequeno das amostras, falta de randomização e ausência de resultados em longo prazo.

Upper airway changes following single-step or stepwise advancement using the Functional Mandibular Advancer.

OBJECTIVES: Purpose of the present study was to determine and compare possible changes in the dimensions of the pharyngeal airway, morphology of the soft palate, and position of the tongue and hyoid bone after single-step or stepwise mandibular advancement using the Functional Mandibular Advancer (FMA). PATIENTS AND METHODS: The sample included 51 peak-pubertal Class II subjects. In all, 34 patients were allocated to two groups using matched randomization: a single-step mandibular advancement group (SSG) and a stepwise mandibular advancement group (SWG). Both groups were treated with FMA followed by fixed appliance therapy; the remaining 17 subjects who underwent only fixed appliance therapy constituted the control group (CG). The study was conducted using pre- and posttreatment lateral cephalometric radiographs. Data were analyzed by paired t test, one-way analysis of variance, and Pearson's correlation coefficient. RESULT: In the SWG and SSG, although increases in nasopharyngeal airway dimensions were not significant compared with those in the CG, enlargements in the oropharyngeal airway dimensions at the level of the soft palate tip and behind the tongue, and decreases in soft palate angulation, were significant. Tongue height increased significantly only in the SWG. Compared with the CG, while forward movement of the hyoid was more prominent in SSG and SWG, the change in the vertical movement of the hyoid was not significant. No significant difference between SWG and SSG was observed in pharyngeal airway, soft palate, tongue or hyoid measurements. CONCLUSIONS: The mode of mandibular advancement in FMA treatment did not significantly affect changes in the pharyngeal airway, soft palate, tongue, and hyoid bone.

Skeletal Class III malocclusion treatment using mandibular and maxillary skeletal anchorage and intermaxillary elastics: a case report

ABSTRACT Introduction: Skeletal Class III malocclusion is one of the most challenging malocclusions to treat. In around 40% of Class III patients, maxillary retrognathia is the main cause of the problem and in most patients, orthopedic/surgical treatments includes some type of maxillary protraction. Objective: The aim of this case report was to describe a treatment method for a patient with maxillary retrognathia and Class III skeletal discrepancy using mandibular and maxillary skeletal anchorage with intermaxillary elastics. Case report: A 13-year-old boy with maxillary retrognathia and mandibular prognathism was treated using bilateral miniplates. Two miniplates were inserted in the mandibular canine area and two other miniplates were placed in the infrazygomatic crests of the maxilla. Class III intermaxillary elastics were used between the miniplates. Results: After eight months of orthopedic therapy, ANB angle increased by 4.1 degrees and ideal overjet and overbite were achieved. Mandibular plane angle was increased by 2.1 degrees and the palatal plane was rotated counterclockwise by 4.8 degrees. Conclusion: This case showed that the skeletal anchorage treatment method may be a viable option for treating patients with Class III skeletal malocclusion.

RESUMO Introdução: a Classe III esquelética é considerada uma das más oclusões mais difíceis de se tratar. Em cerca de 40% dos pacientes afligidos por ela, a principal causa do problema é o retrognatismo maxilar e, na maioria desses pacientes, o tratamento ortopédico/cirúrgico inclui algum tipo de protração da maxila. Objetivo: o objetivo do presente relato de caso é descrever o método de tratamento de um paciente Classe III com discrepância esquelética e retrognatismo maxilar, usando elásticos intermaxilares e ancoragem esquelética superior e inferior. Relato de caso: paciente de 13 anos de idade, com retrognatismo maxilar e prognatismo mandibular, tratado com miniplacas inseridas bilateralmente. Duas miniplacas foram instaladas na região dos caninos inferiores, e outras duas miniplacas foram inseridas na região da crista infrazigomática maxilar. Elásticos intermaxilares de Classe III foram conectados às miniplacas. Resultados: após 8 meses de tratamento ortopédico, o ângulo ANB aumentou 4,1o e obteve-se sobressaliência e sobremordida ideais. O ângulo do plano mandibular aumentou 2,1o e o plano palatal girou 4,8o no sentido anti-horário. Conclusão: esse caso clínico demonstrou que o método de tratamento com ancoragem esquelética pode ser uma opção válida para pacientes com má oclusão de Classe III esquelética.

Class II malocclusion treatment with the Herbst appliance in patients after the growth peak.

OBJECTIVE: The objective of this study was to evaluate dentoskeletal effects in the treatment of Class II malocclusion performed with the Herbst appliance in patients at post-peak stage of growth. METHODS: The sample consisted of 16 patients with Class II malocclusion and average initial and final ages of 14.04 (ranging from 11.50 to 35.66) and 17.14 (ranging from 13.68 to 38.64) years, respectively, who were treated for an mean time of 2.52 years. Lateral cephalograms were obtained at treatment onset (T1) and completion (T2) to evaluate the effects of therapy. Initial dental casts were also used to evaluate the overjet and the anteroposterior severity of molar relationship at treatment onset. The cephalometric changes between initial and final stages were compared by means of the non-parametric Wilcoxon test. RESULTS: The results showed that the Herbst appliance did not promote significant changes in the maxillary component and the effective length of the mandible significantly increased without improving the maxillomandibular relationship. Changes in the maxillary and mandibular dentoalveolar components revealed that the maxillary incisors exhibited retrusion and lingual tipping, while the mandibular incisors presented increased protrusion and buccal tipping. The dental relationships exhibited significant improvements with the treatment. CONCLUSION: Based on the present results, it was concluded that the effects of treatment performed with the Herbst appliance in patients at post-peak stage of growth are predominantly of dentoalveolar nature.

The influence of fränkel-2 function regulator in the lower anterior teeth crown length / Influência da utilização do regulador de função frankel-2 no comprimento da coroa clínica dos dentes anteriores inferiores

Functional orthopedic appliances used for Class II malocclusion treatment, usually work by guiding jaws growth and modifying dental positions. Among these dentoalveolar effects, it is the lower incisors buccal tipping, that helps to improve the overjet, but may cause gingival recessions, especially when associated with other etiological factors. The objective of this study was to evaluate the clinical crown length of the lower anterior teeth in individuals with Angle's Class II malocclusion, after treatment with Fränkel-2 function regulator appliance (RF-2). Fifty Class II-malocclusion individuals were divided into 2 groups: G1 ­ 14 male, and 11 female, treated with the Fränkel-2 function regulator appliance for 18 months, with average pre-treatment age (T1) of 11 years (sd=7 months) and average post-treatment age (T2) of 12 years and 7 months (sd=7 months); and G2 ­ a control group with 25 individuals (12 male and 13 female) with average age at T1 of 10 years and 3 months (sd=11 months) and at T2 of 12 years and 1 month (sd=11 months), which was part of a normal occlusion sample. The 100 dental cast models were analyzed at T1 and T2, with a digital caliper, measuring the distance from the incisal edge to the most concave portion of the gingival margin of lower incisors and canines. Data were checked by a Student's t-test and a paired t-test. Considering T2, the group 1 presented a significant increase in the crown length of all lower anterior teeth. On the other hand, in the group 2, this was observed only for the teeth 33, 42 and 43, suggesting that patients treated with RF-2 had more gingival recession than the control group.

Os aparelhos ortopédicos funcionais utilizados para o tratamento da má oclusão de Classe II normalmente atuam guiando o crescimento dos maxilares e modificando as posições dentais. Dentre esses efeitos dento alveolares está a inclinação dos incisivos inferiores para vestibular, o que auxilia na melhora do overjet, mas pode causar recessões gengivais, especialmente se associado a outros fatores etiológicos. O objetivo deste estudo foi avaliar o comprimento da coroa clínica dos dentes anteriores inferiores em indivíduos com má oclusão de Classe II, após o tratamento com o aparelho regulador de função Fränkel-2 (RF-2). Cinquenta indivíduos com Classe II foram divididos em dois grupos: G1 ­ 14 meninos e 11 meninas, tratados com o aparelho regulador de função Frankel-2, por 18 meses, com média de idade pré-tratamento (T1) de 11 anos (DP=7 meses) e média de idade pós-tratamento (T2) de 12 anos e 7 meses (DP=7 meses); e G2 ­ um grupo controle com 25 indivíduos (12 meninos e 13 meninas) com média de idade em T1 de 10 anos e 3 meses (DP=11 meses) e em T2 de 12 anos e 1 mês (DP=11 meses), que fazia parte de uma amostra de oclusão normal. Os 100 modelos de gesso foram avaliados em T1 e T2, com um paquímetro digital, medindo a distância da borda incisal à parte mais côncava da margem gengival dos incisivos e caninos inferiores. Os dados foram checados pelo teste t de Student e pelo teste t pareado. Considerando T2, o grupo 1 apresentou um aumento significante no comprimento das coroas de todos os dentes anteriores inferiores. Por outro lado, no grupo 2, isto foi observado somente para os dentes 33, 42 e 43, sugerindo que os pacientes tratados com o RF-2 apresentaram mais recessões gengivais do que o grupo controle.

Class II malocclusion treatment with the Herbst appliance in patients after the growth peak

OBJETIVO: avaliar os efeitos dentoesqueléticos do tratamento da má oclusão de Classe II com o aparelho de Herbst em pacientes que se encontravam na fase pós-pico de crescimento. MÉTODOS: a amostra consistiu de 16 pacientes com má oclusão de Classe II com medianas das idades inicial e final de 14,04 (amplitude 11,50 - 35,66) e 17,14 anos (amplitude 13,68 - 38,64), respectivamente, que foram tratados por um período médio de 2,52 anos. Telerradiografias em norma lateral foram obtidas ao início e final do tratamento para avaliar as alterações decorrentes do tratamento. Os modelos de gesso iniciais foram utilizados para avaliar o trespasse horizontal e a severidade da relação anteroposterior existente entre os molares ao início do tratamento. As alterações cefalométricas entre as fases inicial e final foram comparadas pelo teste não-paramétrico de Wilcoxon. RESULTADOS: os resultados mostraram que o aparelho de Herbst não promoveu alterações significativas no componente maxilar, o comprimento efetivo da mandíbula aumentou significativamente, sem promover uma melhoria da relação maxilomandibular. As alterações dos componentes dentoalveolares superiores e inferiores mostraram que os incisivos superiores apresentaram uma retrusão e inclinação lingual, ao passo que os incisivos inferiores evidenciaram um aumento na protrusão e inclinação para vestibular. As relações dentárias apresentaram uma melhora significativa com o tratamento. CONCLUSÃO: com base nos resultados desse trabalho, concluiu-se que os efeitos da terapia com o aparelho de Herbst em pacientes na fase pós-pico de crescimento são de natureza predominantemente dentoalveolar.

OBJECTIVE: The objective of this study was to evaluate dentoskeletal effects in the treatment of Class II malocclusion performed with the Herbst appliance in patients at post-peak stage of growth. METHODS: The sample consisted of 16 patients with Class II malocclusion and average initial and final ages of 14.04 (ranging from 11.50 to 35.66) and 17.14 (ranging from 13.68 to 38.64) years, respectively, who were treated for an mean time of 2.52 years. Lateral cephalograms were obtained at treatment onset (T1) and completion (T2) to evaluate the effects of therapy. Initial dental casts were also used to evaluate the overjet and the anteroposterior severity of molar relationship at treatment onset. The cephalometric changes between initial and final stages were compared by means of the non-parametric Wilcoxon test. RESULTS: The results showed that the Herbst appliance did not promote significant changes in the maxillary component and the effective length of the mandible significantly increased without improving the maxillomandibular relationship. Changes in the maxillary and mandibular dentoalveolar components revealed that the maxillary incisors exhibited retrusion and lingual tipping, while the mandibular incisors presented increased protrusion and buccal tipping. The dental relationships exhibited significant improvements with the treatment. CONCLUSION: Based on the present results, it was concluded that the effects of treatment performed with the Herbst appliance in patients at post-peak stage of growth are predominantly of dentoalveolar nature.