Functional orthopedic treatment for anterior open bite in children. A systematic review of randomized clinical trials.

PURPOSE: This systematic review aimed to assess the effects of orthopedic functional appliances for anterior open bite (AOB) in primary or mixed dentition children. METHODS: A search for randomized controlled trials (RCT) was conducted in November 2020 in electronic databases with no data or language restrictions. Primary outcomes were skeletal cephalometric variables and adverse events. We used the Cochrane risk-of-bias tool to assess methodological quality and the GRADE approach to assess the certainty of the evidence. RESULTS: We identified five RCTs (220 participants). Very low certainty evidence showed an improvement in overbite (mean difference [MD] 3.60; 95% confidence interval [CI] 2.63-4.57) and in the angulation of the upper incisors to the palatal plane (MD 3.70; 95% CI 0.85-6.55) with Frankel's functional regulator, compared to no treatment. There was no difference in the measured cephalometric variables when comparing removable palatal crib to fixed palatal crib, bonded spurs, and chin cup. When comparing removable versus magnetic bite blocks, a beneficial effect was observed in overbite, overjet, skeletal anteroposterior angular measurements, and skeletal vertical linear measures in the magnetic group. No adverse events were reported. CONCLUSION: There was insufficient evidence to infer the effects of these treatments for AOB, and high-quality RCTs are needed to increase the estimated effects. PROSPERO REGISTER: CRD42020175634, prospectively registered (05 July 2020).

Orthodontists' preferences in the use and timing of appliances for the correction of malocclusions in growing patients / Preferencias de los ortodoncistas en el uso y momento oportuno de uso de aparatos para la corrección de maloclusiones en pacientes en crecimiento

Objective: To evaluate orthodontists' preferences in the use and timing of appliances for the correction of Class II and Class III malocclusions in growing patients and the sociodemographic factors that influence these preferences. Material and Methods: Active members of the Colombian Orthodontics Society (SCO) were invited to complete a previously validated survey on the use of Class II and Class III correctors in growing patients. Results: 180 orthodontists responded (80 male, 100 female). The appliances used most frequently in the treatment of Class II malocclusion were Planas indirect tracks (32.78%) and Twin-blocks (30.56%). Facemasks (62.22%) and Progenie plates (25%) were the most prevalent appliances used in the treatment of Class III malocclusions. Regarding treatment timing, 52% of the orthodontists stated that Class II malocclusions must be treated during late mixed dentition or early permanent dentition, 42% stated that treatment for Class III malocclusions should occur during early mixed dentition. Appliance use and treatment timing were significantly associated with sex (p= 0.034), years of practice (p= 0.025), and area of work (private clinics or public institutions), (p= 0.039). Conclusion: Twin-blocks and Facemask appliances were the preferred appliances for Class II and Class III treatment, respectively, in growing patients. Most of the orthodontists believed that Class II malocclusions must be treated during late mixed dentition and that Class III malocclusions must be treated during early mixed dentition. Sociodemographic variables are related factors that influence orthodontists' preferences in the use of these appliances.

Objetivo: Evaluar las preferencias de los ortodoncistas en el uso y momento oportuno de uso de aparatología para la corrección de maloclusiones Clase II y Clase III en pacientes en crecimiento y los factores sociodemográficos que influyen en estas preferencias. Material y Métodos: Se invitó a miembros activos de la Sociedad Colombiana de Ortodoncia (SCO) a completar una encuesta previamente validada, sobre el uso de correctores para Clase II y Clase III en pacientes en crecimiento. Resultados: Respondieron un total de 180 ortodoncistas (80 hombres, 100 mujeres). La aparatología más utilizada en el tratamiento de las maloclusiones de Clase II fueron pistas indirectas de Planas (32,78%) y bloques gemelos (30,56%). La máscara facial (62,22%) y las placas progenie (25%) fueron los aparatos más utilizados en el tratamiento de las maloclusiones de Clase III. En cuanto al momento oportuno del tratamiento, el 52% de los ortodoncistas afirmó que las maloclusiones de Clase II deben tratarse durante la dentición mixta tardía o la dentición permanente temprana, el 42% afirmó que el tratamiento para las maloclusiones de Clase III debe ocurrir durante la dentición mixta temprana. El uso de aparatos y el momento oportuno del tratamiento se asociaron significativamente con el sexo (p= 0,034), los años de práctica (p= 0,025) y el área de trabajo (clínicas privadas o instituciones públicas) (p= 0,039). Conclusión: Los aparatos bloques gemelos y la máscara facial fueron los preferidos para el tratamiento de Clase II y Clase III, respectivamente, en pacientes en crecimiento. La mayoría de los ortodoncistas consideran que las maloclusiones de Clase II deben tratarse durante la dentición mixta tardía y que las maloclusiones de Clase III deben tratarse durante la dentición mixta temprana. Las variables sociodemográficas son factores relacionados que influyen en las preferencias de los ortodoncistas en el uso de estos aparatos.

Efectividad del Bionator de California en la disminución del grado de severidad de los trastornos temporomandibulares / Effectiveness of the California Bionator in reducing the degree of severity of temporomandibular disorders

RESUMEN Fundamento: Existen modalidades de tratamiento para los trastornos temporomandibulares, una de ellas es la Ortopedia funcional de los maxilares. Objetivo: Evaluar la efectividad del Bionator de California en la disminución del grado de severidad de los trastornos temporomandibulares. Metodología: Se realizó estudio experimental, abierto, controlado y aleatorizado en el servicio de Prótesis Estomatológica de la Clínica Estomatológica de Fomento en el período de septiembre de 2019 a septiembre de 2021. Se seleccionaron 60 pacientes con trastornos temporomandibulares que cumplieron los criterios de selección, mediante asignación aleatoria se establecieron los grupos: Estudio (tratado con Bionator de California) y control (tratado con férula neuromiorrelajante). Se utilizaron métodos del nivel teórico, empírico y estadístico. La variable de respuesta principal fue: Efectividad del Bionator de California en el grado de severidad del trastorno temporomandibular. Resultados: Al inicio del estudio predominó la severidad moderada de trastornos temporomandibulares en ambos grupos, pero a los 6 meses de tratamiento predominaron los asintomáticos (66.7 %) en el grupo estudio y 36.7 % en el grupo control, con diferencia estadísticamente significativa entre ambos grupos. Conclusiones: El tratamiento con el Bionator de California fue efectivo porque se logró disminuir el grado de severidad de los trastornos temporomandibulares.

ABSTRACT Background: There are treatment modalities for temporomandibular disorders, one of them is functional orthopedics of the jaws. Objective: To evaluate the effectiveness of the California Bionator in reducing the degree of severity of temporomandibular disorders. Methodology: An experimental, open, controlled and randomized study was carried out in the Dental Prosthesis service at Fomento Dental Clinic from September 2019 to September 2021. 60 patients with temporomandibular disorders who met the selection criteria were selected. The groups were established by random assignment: Study (treated with Bionator from California) and control (treated with a neuromyorelaxant splint). Method theoretical, empirical and statistical levels were used. The main response variable was: Effectiveness of the California Bionator in the degree of severity of the temporomandibular disorder. Results: At the beginning of the study moderate severity of temporomandibular disorders prevailed in both groups, but after 6 months of treatment asymptomatic predominated (66.7%) in the study group and 36.7% in the control group, with a statistically significant difference between both groups. Conclusions: The treatment with the California Bionator was effective because the degree of severity of temporomandibular disorders was reduced.

Tratamiento con Activador Abierto Elástico de Klammt en pacientes con Síndrome de Clase III / Treatment with Klammt Elastic Open Activator in patients with Class III Syndrome

RESUMEN Introducción: en los últimos años se utilizan con éxito una gama de aparatos funcionales para las Clases III. Uno de ellos es el Activador Abierto Elástico de Klammt, que presenta un diseño sencillo, a diferencia de otros aparatos que son empleados para corregir este tipo de maloclusión. Objetivo: evaluar la eficacia del tratamiento con activador abierto elástico de Klammt en el Síndrome de Clase III. Métodos: se realizó un estudio analítico, longitudinal, prospectivo, en el servicio de Ortodoncia de la Clínica Estomatológica "José Martí" de Consolación del Sur, Pinar del Río. El universo estuvo constituido por 15 pacientes con síndrome de Clase III, la muestra se conformó por 10 pacientes que cumplieron con los criterios de inclusión. Se realizó a cada paciente el diagnóstico clínico y estudio cefalométrico antes y después del tratamiento ortodóncico. Resultados: luego del tratamiento, se produjeron cambios positivos en el sobrepase, relación molar y resalte incisivo. Los resultados cefalométricos esqueletales más notables fueron: un aumento del ángulo ANB por la disminución del SNB, además de la disminución de la longitud mandibular. Estos resultados fueron corroborados al aplicar la prueba no paramétrica de Wilcoxon para un nivel de significación de 0,05. Conclusiones: el Activador Abierto Elástico de Klammt constituye un método eficaz en pacientes con Síndrome de Clase III, sobre todo cuando se emplea desde edades tempranas.

ABSTRACT Introduction: in recent years a range of functional appliances has been successfully used for Class III. One of them is Klammt Open Elastic Activator, which has a simple design, unlike other devices that are used to correct this type of malocclusion. Objective: to evaluate the effectiveness of Klammt elastic open activator treatment in Class III Syndrome. Methods: an analytical, longitudinal and prospective study was carried out at José Martí Orthodontic Service Clinic in Consolación del Sur, Pinar del Río. The target group consisted of 15 patients with Class III syndrome, the sample was comprised of 10 patients who met the inclusion criteria. Clinical diagnosis and cephalometric studies were performed on each patient and after orthodontic treatment. Results: after treatment, there were positive changes in the overpass, molar relation and incisor protrusion. The most notable cephalometric-skeletal results were: an increase in the ANB angle due to a decrease in the SNB, as well as a decrease in mandibular length. These results were corroborated by applying the Wilcoxon nonparametric test for a significance level of 0.05. Conclusions: Klammt Open Elastic Activator is an effective method in patients with Class III Syndrome, especially when it is applied in early ages.

Esthetic perception of facial profile changes after extraction and nonextraction Class II treatment

Abstract This retrospective study evaluated facial profile pleasantness determined by two protocols of Class II treatment. The sample comprised facial profile silhouettes obtained retrospectively from the pretreatment (T1) and posttreatment (T2) cephalograms of 60 patients (42 males and 18 females) divided into two groups. One group of 30 patients (mean age of 12.84 years) was treated with the extraction of maxillary first premolars (mean treatment time of 2.7 years), and the other group of 30 patients (mean age of 12.81 years) was treated with a mandibular advancement appliance (Forsus) (mean treatment time of 2.49 years). The facial profile silhouettes (T1 and T2) were randomly distributed in an album containing one patient per sheet. The examiners consisted of 60 orthodontists and 60 lay individuals, who analyzed the profiles in regard to facial pleasantness, using the Likert scale. A comparison between stages T1 and T2 of the two treatment protocols and between the examiners was performed by mixed-design analysis of variance at a significance level of 5%. The results demonstrated a significant difference between T1 and T2 (greater scores for T2 compared to T1), and between lay individuals and orthodontists (orthodontists assigned higher scores), but with no significant difference between the treatment protocols. Both protocols produced positive effects on the facial profile esthetics, from the standpoint of lay individuals and orthodontists.

Effects of Class II division 1 malocclusion treatment with three types of fixed functional appliances

ABSTRACT Objective: This study aimed at comparing the dentoskeletal changes in patients with Class II division 1 malocclusion, treated with three types of fixed functional appliances. Methods: A sample comprising 95 patients with the same malocclusion, retrospectively selected, and divided into four groups, was used: G1 consisted of 25 patients (mean age 12.77 ± 1.24 years) treated with Jasper Jumper appliance; G2, with 25 patients (mean age 12.58 ± 1.65 years) treated with the Herbst appliance; G3, with 23 patients (mean age 12.37 ± 1.72 years) treated with the Mandibular Protraction Appliance (MPA); and a Control Group (CG) comprised of 22 untreated subjects (mean age 12.66 ± 1.12 years). Intergroup comparison was performed with ANOVA, followed by Tukey test. Results: The Jasper Jumper and the Herbst group showed significantly greater maxillary anterior displacement restriction. The Jasper Jumper demonstrated significantly greater increase in the mandibular plane angle, as compared to the control group. The MPA group demonstrated significantly greater palatal inclination of the maxillary incisors. Vertical development of the maxillary molars was significantly greater in the Herbst group. Conclusions: Despite some intergroup differences in the amount of dentoskeletal changes, the appliances were effective in correcting the main features of Class II malocclusions.

RESUMO Objetivo: o objetivo do presente estudo foi comparar as alterações dentoesqueléticas em pacientes com má oclusão de Classe II, divisão 1, tratados com três tipos de aparelhos funcionais fixos. Métodos: a amostra compreendeu 95 pacientes, selecionados retrospectivamente e divididos em quatro grupos: G1, composto por 25 pacientes (idade média de 12,77 ± 1,24 anos), tratados com aparelho Jasper Jumper; G2, com 25 pacientes (idade média de 12,58 ± 1,65 anos), tratados com aparelho Herbst; G3, com 23 pacientes (idade média de 12,37 ± 1,72 anos), tratados com o Aparelho de Protração Mandibular (APM); e um Grupo Controle (GC), composto por 22 sujeitos não tratados (idade média de 12,66 ± 1,12 anos) que apresentavam a mesma má oclusão. A comparação intergrupos foi realizada com ANOVA, seguida do teste Tukey. Resultados: os grupos Jasper Jumper e Herbst apresentaram significativamente maior restrição de deslocamento anterior da maxila. O Jasper Jumper demonstrou aumento significativamente maior no ângulo do plano mandibular, em comparação ao grupo controle. O grupo APM demonstrou inclinação palatina significativamente maior dos incisivos superiores. O desenvolvimento vertical dos molares superiores foi significativamente maior no grupo Herbst. Conclusões: apesar de algumas diferenças intergrupos na quantidade de alterações dentoesqueléticas, os aparelhos foram eficazes na correção das principais características das más oclusões de Classe II.

[A review of the effectiveness and long-term stability of the functional appliance].

The orthopedic treatment of the orthodontics is a typical and crucial technique and method that uses functional appliances to fully work out the potentials of the jaws and muscles, and accordingly to correct the functional or mild skeletal malocclusions in pre-pubertal children and adolescents. A successful orthopedic treatment involves its short-time effectiveness and its long-term stability. For many years, however, the effectiveness of the functional appliance is controversial and the long-term stability of the functional appliance has always been overlooked. Thus, with an aim of presenting guidelines on orthopedic treatment, the effectiveness and the long-term stability of the functional appliance are discussed in this article.

A review of the effectiveness and long-term stability of the functional appliance / 中华口腔医学杂志

The orthopedic treatment of the orthodontics is a typical and crucial technique and method that uses functional appliances to fully work out the potentials of the jaws and muscles, and accordingly to correct the functional or mild skeletal malocclusions in pre-pubertal children and adolescents. A successful orthopedic treatment involves its short-time effectiveness and its long-term stability. For many years, however, the effectiveness of the functional appliance is controversial and the long-term stability of the functional appliance has always been overlooked. Thus, with an aim of presenting guidelines on orthopedic treatment, the effectiveness and the long-term stability of the functional appliance are discussed in this article.

Long-term stability of Class II division 1 treatment with the MARA combined with fixed appliances / Avaliação da estabilidade em longo prazo da correção da Classe II divisão 1 com aparelho MARA associado ao aparelho ortodôntico fixo

Introduction: Successful treatment of class II Division 1 malocclusion is also implied to the long-term stability of treatment changes and many are the factors that can influence that. Objective: This research aimed to evaluate the long-term stability of the cephalometric changes obtained during Class II malocclusion correction with the MARA (Mandibular Anterior Repositioning Appliance) associated with fixed appliances. Methods: The treatment group comprised 12 patients who were evaluated at three stages: pretreatment (T1), posttreatment (T2) and long-term posttreatment (T3). The mean initial age of the patients was 12.35 years and the mean final age was 15.65 years. The mean age at the long-term posttreatment stage was 22.53 years and the mean long-term posttreatment period was 6.88 years. The control group comprised 12 subjects with normal occlusion and no orthodontic treatment with ages comparable to the treatment group at the posttreatment and long-term posttreatment stages. Intra-treatment group comparison between the three stages was performed with repeated measures analysis of variance (ANOVA), followed by Tukey tests. Intergroup comparison of posttreatment changes and normal growth changes of the treatment group were performed with t tests. Results: reduction of the maxillary protrusion and improvement of the maxillomandibular relationships remained stable during the long-term posttreatment period. Maxillary incisors inclination and overjet presented a tendency to relapse in relation to the control group Conclusions: Despite the different amount of growth potential, the reduction of the maxillary protrusion and maxillomandibular relationship improvement remained stable with no difference from normal occlusion behavior. Palatal inclination of the maxillary incisors and the overjet improvement showed a slight tendency towards relapse when compared to normal occlusion. Therefore, an increase of active retention time could be recommended to prevent that.(AU)

Introdução: o tratamento bem-sucedido da má oclusão de classe II Divisão 1 está implícito na estabilidade em longo prazo das correções e muitos são os fatores que podem influenciar esta estabilidade. Objetivos: observando que a terapia com o aparelho MARA (Mandibular Anterior Repositioning Appliance) associado ao aparelho ortodôntico fixo mostrou-se eficaz na correção da Classe II, este trabalho estabeleceu como objetivo avaliar cefalometricamente a estabilidade em longo prazo das correções obtidas durante este tratamento. Materiais e métodos: foram analisadas as alterações durante e após o tratamento através das telerradiografias em norma lateral de 12 pacientes (09 meninos e 03 meninas) nas fases: inicial (T1), final (T2) e pós-tratamento (T3), com idade média inicial de 12,35 anos e 15,65 anos ao final do tratamento. A idade media no estágio de pós tratamento em longo prazo foi de 22,53 e o tempo de acompanhamento pós tratamento foi em media 6,88 anos. As alterações foram comparadas a um Grupo Controle com oclusão normal, não tratados ortodonticamente, com idades compatíveis ao grupo experimental nos estágios final e pós tratamento em longo prazo. Os dados obtidos foram analisados através da análise de variância (ANOVA) para medidas repetidas e o teste de comparações múltiplas de Tukey. As alterações ocorridas no período de póstratamento foram comparadas com as alterações do Grupo Controle durante o período correspondente utilizando o teste t independente. Resultados: Observou-se uma redução da protrusão maxilar, assim como, uma melhora das relações maxilomandibulares, as quais, permaneceram estáveis durante o período de póstratamento. A inclinação dos incisivos superiores e o overjet apresentaram tendência à recidiva em relação ao grupo controle. Conclusões: A redução da protrusão maxilar e melhora da relação maxilomandibular mantiveram-se estáveis, sem diferença estatisticamente significante do comportamento na oclusão normal. A retroinclinação dos incisivos superiores e a melhora do overjet mostraram uma ligeira tendência à recidiva quando comparada ao comportamento da oclusão normal. Portanto, um aumento do tempo de retenção ativo pode ser recomendado para evitar essa recidiva.(AU)

Resultados del tratamiento de maloclusión clase II división 1 con activador abierto elástico de Klammt / Results of type II division 1 malocclusion treatment, with Klammt elastic open activator

Fundamento: El activador abierto elástico de Klammt ha sido utilizado en Cuba en los últimos años. Es un aparato funcional que se encuentra entre las opciones de tratamiento de la maloclusión clase II división 1.Objetivo: describir los resultados del tratamiento ortopédico para la corrección de maloclusión clase II división 1 con activador abierto elástico de Klammt.Métodos: se realizó un estudio de intervención, cuasiexperimental, que incluyó a 20 niños de la escuela primaria Antonio Maceo, del Área de Salud II del municipio Cienfuegos. Para el diagnóstico se tomaron telerradiografías laterales de cráneo al inicio y al año de tratamiento, a las cuales se aplicaron mediciones lineales y/o angulares de Steiner, Ricketts y McNamara. Se evaluaron los cambios cefalométricos esqueletales y de tejidos blandos antes y después del tratamiento.Resultados: se observaron cambios en las mediciones de las radiografías laterales del cráneo, con variaciones cefalométricas cráneofaciales de significación estadística importante; lo mismo ocurrió en los tejidos blandos, que denotaron en general un mejoramiento del perfil, sobre todo del ángulo nasolabial, esencialmente originado en su componente labial.Conclusión: se constató la efectividad del activador abierto elástico de Klammt en el tratamiento de las maloclusiones clase II división 1, ya que se logró la corrección de estas en pacientes de edades tempranas, lo cual se evidenció en las variaciones resultantes en el biotipo facial hacia patrones más favorables.

Foundation: Klammt elastic open activator has been used in Cuba in the last years. It is a fuctional aparathus whis is found among the treatment options for type II division 1 maloclussion. Objective: To describe Klammt elastic open activator for correcting type II division 1 maloclussion with Klammt elastic open activator.Methods: A quasi-experimental intervention was carried out, including 20 children from the Antonio Maceo elementary school, from the Cienfuegos municipality Health Area II. For the diagnosis skull lateral cephalograms were taken at the beginning and at a year time from treatment beginning, to which linear and/or angular measurements of Steiner, Ricketts and McNamara were applied. Changes in measurements of skull lateral radiographs were observed, with cephalometric variations of craniofacial of important statistical significance; the same occurred in soft tissues, which generally denoted an improvement of the profile, especially of the nasolabial angle, essentially originating in its labial component. Skeletal and soft tissue cephalometric changes were evaluated before and after treatment.Results: Changes in measurements of skull lateral radiographs were observed, with cephalometric variations of craniofacial of important statistical significance; The same occurred in soft tissues, which generally denoted a profile improvement, especially of the nasolabial angle, essentially originating in its labial component.Conclusion: The effectiveness of Klammt elastic open activator in the treatment of class II malocclusions division 1 was verified, as it was corrected in patients of early age, which was evidenced in the resulting variations in the facial biotype towards more favorable patterns.

[Relationship between the mandibular hypoplasia and temporomandibular joint internal derangement in adolescents with skeletal class â ¡ malocclusion].

Mandibular hypoplasia is very common clinically. Studies have reported that temporomandibular joint internal derangement (TMJID) might manifest as mandibular retrusion, and whether there is a direct correlation between them remains controversial in academia. On the other hand, for adolescent patients with skeletal class Ⅱ malocclusion, the growth of mandible could be motivated by orthopedic force, and then the mandibular retrusion corrected. However, if TMJID is the direct cause of mandibular retrusion, orthopedic treatment will not have a significant effect on it. Base on literature review and analysis as well as our own research, this article will review the distribution of structural abnormalities of the temporomandibular joint in adolescents with mandibular hypoplasia and its association with skeletal class Ⅱ malocclusion, as well as the effect of TMJID on the treatment of skeletal class Ⅱ malocclusion in adolescents.

[MRI analysis of the effect on mandibular retrusion with anterior disc displacement treated by using Herbst appliance].

Objective: To investgate the effect of Herbst appliance on the growth and remodeling of the temporomandibular joint (TMJ) in class Ⅱ patients with mandibular retrusion by using MRI. Methods: Between December 2010 and October 2014, 12 class Ⅱ patients (11-16 years old) with mandibular retrusion were chosen. The patients were divided into two groups. The control group included 7 patients (14 joints) with normal disc condyle relationship and the anterior disc displacement (ADD) group included 5 patients (10 joints) with anterior disc displacement. The MRI images of TMJ were measured, including condylar height, joint space index and disc position ratio, before and after the treatment. Results: The condylar height of the patients in the control group was significantly increased (P<0.001) after treatment, and no significant difference in joint space index (P=0.821) and disc position ratio (P=0.146) was found. The joint space index of the patients ([-14.70±8.82]% and [4.90±11.35]%) in ADD group changed significantly (P<0.001) after treatment, and no significant difference in condylar height (P=0.294) and disc position ratio (P=0.120) was found. Conclusions: The normal disc condyle relationship was beneficial to the reconstruction of the condylar process, and the increase of the condylar height. The condyle moved forward in patients with anterior disc displacement after treatment.

[A cone-beam CT investigation on condylar growth in beagle dog treated with Herbst appliance and prostaglandin E2 during late stage of growth].

Objective: To assess the mandibular condylar growth using cone-beam CT (CBCT) in beagle dogs treated with Herbst appliance and exogenous prostaglandin E2 (PGE2) during late stage of growth. Methods: Twenty-four male beagle dogs aged 8 months were divided into four groups according to the random number table (n=6 in each group): natural growth group, mandibular protraction group (Herbst group), injected prostaglandin E2 group (PGE2 group), mandibular protraction plus injected prostaglandin E2 group (Herbst+PGE2 group). The beagle dogs in Herbst+PGE2 group and PGE2 group were injected 0.1 ml of prostaglandin E2 (dose of 0.05 mg) into bilateral temporomandibular joint articular cavity. The dogs in natural growth group and Herbst group were injected 0.1 ml of saline into bilateral temporomandibular joint articular cavity as control. PGE2 and saline were injected once every 3 days for 60 days, respectively. CBCT was taken before the application of Herbst appliance and after removal of the appliance for all beagle dogs in four groups at the same time. The CBCT images were reconstructed using Invivo5 software and the relevant parameters of temporomandibular joint were measured. Results: No significant difference was found in natural growth group before and after the experiment (P>0.05). After the treatment, the condylar height and condylar size in Herbst group ([0.19+0.04] and [0.18+0.30] mm), PGE2 group ([0.38+0.14] and [0.51+0.24] mm) and Herbst+PGE2 group ([0.65+0.08] and [0.70+0.24] mm) slightly increased (P<0.05). The condylar changes in all experimental groups were greater than the natural growth group (P<0.05), and the ranges of change, in descending order, were Herbst+PGE2 group, PGE2 group and Herbst group (P<0.05). However, the condylar longitudinal distances, condyle width, condylar transverse diameter, glenoid fossa width and glenoid fossa depth had no statistically significant difference among the four groups (P>0.05). Conclusions: Injection of exogenous PGE2 into the temporomandibular joint articular cavity, or using Herbst appliance separately, a certain amount of growth was observed on the mandibular condyle in beagle dogs during late stage of growth. The combination of Herbst appliance and exogenous PGE2 injection made the condylar growth more obviously.

A cone-beam CT investigation on condylar growth in beagle dog treated with Herbst appliance and prostaglandin E2 during late stage of growth / 中华口腔医学杂志

Objective@#To assess the mandibular condylar growth using cone-beam CT (CBCT) in beagle dogs treated with Herbst appliance and exogenous prostaglandin E2 (PGE2) during late stage of growth.@*Methods@#Twenty-four male beagle dogs aged 8 months were divided into four groups according to the random number table (n=6 in each group): natural growth group, mandibular protraction group (Herbst group), injected prostaglandin E2 group (PGE2 group), mandibular protraction plus injected prostaglandin E2 group (Herbst+PGE2 group). The beagle dogs in Herbst+PGE2 group and PGE2 group were injected 0.1 ml of prostaglandin E2 (dose of 0.05 mg) into bilateral temporomandibular joint articular cavity. The dogs in natural growth group and Herbst group were injected 0.1 ml of saline into bilateral temporomandibular joint articular cavity as control. PGE2 and saline were injected once every 3 days for 60 days, respectively. CBCT was taken before the application of Herbst appliance and after removal of the appliance for all beagle dogs in four groups at the same time. The CBCT images were reconstructed using Invivo5 software and the relevant parameters of temporomandibular joint were measured.@*Results@#No significant difference was found in natural growth group before and after the experiment (P>0.05). After the treatment, the condylar height and condylar size in Herbst group ([0.19+0.04] and [0.18+0.30] mm), PGE2 group ([0.38+0.14] and [0.51+0.24] mm) and Herbst+PGE2 group ([0.65+0.08] and [0.70+0.24] mm) slightly increased (P<0.05). The condylar changes in all experimental groups were greater than the natural growth group (P<0.05), and the ranges of change, in descending order, were Herbst+PGE2 group, PGE2 group and Herbst group (P<0.05). However, the condylar longitudinal distances, condyle width, condylar transverse diameter, glenoid fossa width and glenoid fossa depth had no statistically significant difference among the four groups (P>0.05).@*Conclusions@#Injection of exogenous PGE2 into the temporomandibular joint articular cavity, or using Herbst appliance separately, a certain amount of growth was observed on the mandibular condyle in beagle dogs during late stage of growth. The combination of Herbst appliance and exogenous PGE2 injection made the condylar growth more obviously.

MRI analysis of the effect on mandibular retrusion with anterior disc displacement treated by using Herbst appliance / 中华口腔医学杂志

Objective@#To investgate the effect of Herbst appliance on the growth and remodeling of the temporomandibular joint (TMJ) in class Ⅱ patients with mandibular retrusion by using MRI.@*Methods@#Between December 2010 and October 2014, 12 class Ⅱ patients (11-16 years old) with mandibular retrusion were chosen. The patients were divided into two groups. The control group included 7 patients (14 joints) with normal disc condyle relationship and the anterior disc displacement (ADD) group included 5 patients (10 joints) with anterior disc displacement. The MRI images of TMJ were measured, including condylar height, joint space index and disc position ratio, before and after the treatment.@*Results@#The condylar height of the patients in the control group was significantly increased (P<0.001) after treatment, and no significant difference in joint space index (P=0.821) and disc position ratio (P=0.146) was found. The joint space index of the patients ([-14.70±8.82]% and [4.90±11.35]%) in ADD group changed significantly (P<0.001) after treatment, and no significant difference in condylar height (P=0.294) and disc position ratio (P=0.120) was found.@*Conclusions@#The normal disc condyle relationship was beneficial to the reconstruction of the condylar process, and the increase of the condylar height. The condyle moved forward in patients with anterior disc displacement after treatment.

Relationship between the mandibular hypoplasia and temporomandibular joint internal derangement in adolescents with skeletal class Ⅱ malocclusion / 中华口腔医学杂志

Mandibular hypoplasia is very common clinically. Studies have reported that temporomandibular joint internal derangement (TMJID) might manifest as mandibular retrusion, and whether there is a direct correlation between them remains controversial in academia. On the other hand, for adolescent patients with skeletal class Ⅱ malocclusion, the growth of mandible could be motivated by orthopedic force, and then the mandibular retrusion corrected. However, if TMJID is the direct cause of mandibular retrusion, orthopedic treatment will not have a significant effect on it. Base on literature review and analysis as well as our own research, this article will review the distribution of structural abnormalities of the temporomandibular joint in adolescents with mandibular hypoplasia and its association with skeletal class Ⅱ malocclusion, as well as the effect of TMJID on the treatment of skeletal class Ⅱ malocclusion in adolescents.

Mordida cruzada anterior y recesión periodontal: Tratamiento con el MUH Shield. Reporte de caso / Anterior cross bite and periodontal recession: Treatment with the MUH Shield. Case report

Fundamento: Según el Programa Nacional de Atención Estomatológica Integral, se observa una disminución de la prevalencia de caries dental en la población infantil y adolescente, mientras que las periodontopatías ocupan el segundo lugar en la jerarquización de las enfermedades bucales, y la Organización Mundial de la Salud las considera entre las afecciones más comunes del género humano. Entre los factores causantes de recesión periodontal se encuentran la malposición dentaria, las inserciones frénicas anormales y los defectos de la oclusión. Objetivo: Descruzar la mordida anterior simple, asimismo mejorar el estado periodontal del paciente con el aparato tipo MUH Shield. Reporte del caso: Paciente masculino de raza negra, ocho años de edad, con antecedentes de retención dentaria temporal, que acudió a consulta por maloclusión, con trastorno mucogingival asociado a una mordida cruzada anterior simple, sobrepase de 2 mm, resalte de 1 mm. Conclusiones: Se logró descruzar la mordida anterior a las nueve semanas de tratamiento con el aparato tipo MUH Shield y se mejoró el estado periodontal del paciente.

ABSTRACT Background: According to the National Program of Integral Stomatological Care, there is a decrease in the prevalence of dental cavities in children and adolescents, while periodonthopathies rank second in the hierarchy of oral diseases, and the World Organization of Health considers them among the most common conditions of mankind. Among the factors causing periodontal recession are dental miss position, abnormal phrenic insertions, and defects of occlusio. Objective: To uncross the simple anterior bite, as well as to improve the periodontal status of the patient with the MUH Shield type device Case report: An eight years old white male patient, with a history of temporary dental retention, who came to the clinic due to malocclusion, with a bucogingival disorder associated with a simple anterior cross bite, exceeding 2 mm, and a 1 mm margin Conclusions: The anterior bite was uncrossed after nine weeks of treatment with the MUH Shield type device and the patient's periodontal status was improved.

A comparative study of the MARA appliance and the activator-headgear combination in the treatment of class II division 1 malocclusion / Estudo comparativo dos aparelhos MARA e ativador combinado com AEB no tratamento da má oclusão de classe II divisão 1

O tratamento da má oclusão de Classe II Divisão 1, usando aparelhos ortopédicos associados ao aparelho ortodôntico fixo, mostrou excelentes resultados, quando usado em pacientes em crescimento. Este estudo teve como objetivo comparar os efeitos do tratamento da correção de Classe II com os aparelhos MARA (G1) e o Ativador combinado ao AEB (G2) e um grupo controle não tratado (G3). Cada grupo experimental foi constituído por 18 pacientes, com idade média de 11,70 (G1) e 10,88 (G2), tratados por tempo médio de 3,60 (G1) e 3,17 (G2) anos. O grupo controle (G3) consistiu de 20 indivíduos com idade média de referência de 11,07 anos. Os grupos foram avaliados antes (T1) e após (T2) o tratamento. Telerradiografias laterais foram utilizadas para avaliar as alterações esqueléticas e dentoalveolares após o tratamento (T2-T1), sendo utilizado um período comparável para o grupo controle. As comparações intergrupos em relação às alterações do tratamento foram realizadas usando a Análise de Variância (ANOVA), seguidas pelo teste de Tukey. Os efeitos dentoalveolares e a restrição maxilar melhoraram a relação maxilomandibular em G1 e G2. As alterações mandibulares foram decorrentes principalmente do crescimento craniofacial natural, sem alterações significativas nos tecidos moles. Concluiu-se que ambos os aparelhos corrigiram similarmente a má oclusão de Classe II.(AU)

The treatment of Class II Division 1 malocclusion using orthopedic devices combined with fixed orthodontic appliances has shown excellent results when used in growing patients. This study aimed to compare the treatment effects of Class II correction with MARA appliance (G1), AcHg combination appliance (G2), and an untreated control group (G3). Each experimental group was composed of 18 patients, with a baseline mean age of 11.70 (G1) and 10.88 (G2) years, treated for a mean time of 3.60 (G1) and 3.17 (G2) years. The control group (G3) consisted of 20 individuals with a baseline mean age of 11.07 years. The groups were evaluated before (T1) and after (T2) treatment. Lateral cephalometric radiographs were used to evaluate skeletal and dentoalveolar changes upon treatment (T2-T1), and a comparable period was used for the control group. Intergroup comparisons regarding treatment changes were performed using repeated measures analysis of variance (ANOVA) followed by Tukey's test. The dentoalveolar effects and maxillary restriction improved the maxillomandibular relationship in G1 and G2. Mandibular alterations were mainly due to natural craniofacial growth, with no significant alterations of soft tissues. It was concluded that both the appliances corrected similarly the Class II malocclusion.(AU)