Three-dimensional finite element study of mandibular first molar distalization with clear aligner / 华西口腔医学杂志

OBJECTIVES@#This study aimed to construct the finite element model of the mandibular first molar with the invisible appliance and explore the dentition movement characteristics of the mandibular first molar when using micro-implant anchorage and different initial positions of the first molar.@*METHODS@#Models of the mandible, tooth, periodontal membrane, and invisible appliance were constructed using cone beam computed tomography (CBCT) data. The two groups were divided into the non-anchorage group and the micro-implant group (between the roots of the first molar and the second molar) based on whether the elastic traction of the micro-implant was assisted or not. The two groups were divided into the following conditions based on the starting position of the first molar: Working condition 1: the distance between the first molar and the second premolar was 0 mm; working condition 2: the distance between the first molar and the second premolar was 1 mm; working condition 3: the distance between the first molar and the second premolar was 2 mm; working condition 4: the distance between the first molar and the second premolar was 3 mm. The data characte-ristics of total displacement and displacement in each direction of dentition were analyzed.@*RESULTS@#In the non-ancho-rage group, all the other teeth showed reverse movement except for the first molar which was moved distally. Meanwhile, in the micro-implant group, except for a small amount of mesial movement of the second molar in wor-king condition 1, the whole dentition in other working conditions presented distal movement and anterior teeth showed lingual movement, among which the distal displacement of the first molar in working condition 4 was the largest. With the change of the initial position of the first molar to the distal, the movement of the first molar to the distal, the premolar to the mesial, and the anterior to the lip increased, while the movement of the second molar to the mesial decreased.@*CONCLUSIONS@#The micro-implant can effectively protect the anterior anchorage, increase the expression rate of molar distancing, and avoid the round-trip movement of the second molar. The initial position of the first molar movement is related to the amount of distancing and the remaining tooth movement.

Morphology changes of maxillary molar distalization by clear aligner therapy / Cambios de la morfología en la distalización de molares maxilares mediante terapia con alineadores transparentes

SUMMARY: To evaluate the skeletal, dento-alveolar and soft tissue morphology changes after maxillary molar distalization by clear aligner therapy and identify the significant efficacy of molar distalization,18 patients in conformity with the inclusion criteria were selected. Pre- and post-treatment Cone Beam Computed Tomography (CBCT) were examined to measure the angular and linear parameters. All subjects were completed non-extraction clear aligner treatment by distalizing molars. A paired-t test and independent-samples t-test were performed to observe the difference between before and after treatment and the difference between the first molar and second molar respectively. P-values <0.05 were considered statistically significant. Predicted movement rate was calculated by the formula: (actual movement(mm)/planned movement(mm)) x100%. Most variables of pre- and post-treatment showed no statistical difference(P<0.05), excepting SNA angle (P<0.05) and Upper lip/E-line linear (P<0.01) due to incisor retraction. The first and second molar revealed a translation movement without significant tipping and vertical movement. Clear aligners provided a high predictability (83.44 %) of distalization the maxillary first molar, and 85.14 % of the maxillary second molar. Clear aligners can effectively achieve distal displacement of molars.

RESUMEN: Se seleccionaron 18 pacientes, de acuerdo con los criterios de inclusión, para evaluar los cambios en la morfología esquelética, dentoalveolar y de los tejidos blandos después de la distalización de los molares maxilares, mediante la terapia con alineadores transparentes e así identificar la significativa eficacia de la distalización de los molares. Se examinó a través de tomografía computarizada de haz cónico (CBCT) antes y después del tratamiento para medir los parámetros angulares y lineales. Todos los sujetos completaron el tratamiento con alineadores transparentes sin extracción mediante la distalización de los molares. Se realizó una prueba t pareada y una prueba t de muestras independientes para observar la diferencia entre antes y después del tratamiento y la diferencia entre el primer molar y el segundo molar, respectivamente. Los valores de p<0,05 se consideraron estadísticamente significativos. La tasa de movimiento prevista se calculó mediante la fórmula: (movimiento real (mm)/movimiento planificado (mm)) x 100 %. La mayoría de las variables de pre y postratamiento no mostraron diferencia estadística (P<0,05), excepto el ángulo SNA (P<0,05) y el labio superior/línea E lineal (P<0,01) debido a la retracción del incisivo. El primer y segundo molar revelaron un movimiento de traslación sin inclinación significativa y movimiento vertical. Los alineadores transparentes proporcionaron una alta previsibilidad (83,44 %) de la distalización del primer molar superior y del 85,14 % del segundo molar superior. Los alineadores transparentes pueden lograr efectivamente el desplazamiento distal de los molares.

Efficacy of mandibular molar distalization by clear aligner treatment / 中南大学学报(医学版)

OBJECTIVES@#At present, the research on clear aligner of molar distalization mainly focuses on the upper jaw, while the research on mandibular molars is few.This study aims to evaluate the therapeutic effect of mandibular molars distalization with clear aligner via cone beam CT (CBCT) and Dolphin software.@*METHODS@#Twenty cases of mandibular molars with clear aligner were included according to the inclusion and exclusion criteria. CBCT was taken before treatment (T0) and when the first molar was moved in place (T1). Dolphin software was used to measure the effectiveness of molar distalization. Three-dimensional changes in direction and the impact on the incisors and facial soft and hard tissues were evaluated.@*RESULTS@#The effective rates of crown and root distalization of the second and first mandibular molars were 74%, 49%, and 71%, 47%, respectively. The second and first molars were both the distal buccal cusp with the largest distalization [(2.15 ± 0.91) mm and (1.85±1.09) mm], respectively, with significant difference between the T0 and T1 (@*CONCLUSIONS@#Clear aligner can effectively move mandibular molars farther, the crown is more effective than the root, and it is tilted. The second mandibular molar is more effective than the first mandibular molar in its distant displacement and three-dimensional changes. Molar distalization causes minor changes in mandibular incisors and facial soft and hard tissues.

Treatment of class II malocclusion and unerupted upper canines with self-ligating appliance

Treatments without tooth extractions have become more popular over the last two decades. In this context, expansion of the maxillary arch is an interesting treatment option for cases in which space is required and other factors not favoring extractions (such as the facial profile) are present. According to several authors, this posterior expansion can be obtained using a system comprising self-ligating brackets and superelastic nickel-titanium arches. The present article aims to report a case of a young patient with Class II, Division 2 malocclusion, with impacted upper canines and significant arch length-tooth discrepancy. Methods: The case was treated by means of a passive self-ligating appliance in association with Class II elastics and coil spring for distalizing the molars. This treatment alternative was effective for correcting Class II and obtaining space to correct tooth positioning.

The clinical effects of Invisalign-aided molar distalization in the treatment of mild or moderate crowding in anterior teeth / 口腔疾病防治

Objective@# The present study evaluated the clinical effects of Invisalign-aided molar distalization in the treatment of mild or moderate crowding in anterior teeth. @*Methods@#Eleven adults with class Ⅱ dental malocclusion and a class Ⅰ skeletal pattern were selected as subjects. The patients’ molar occlusion did not exhibit an end-to-end relationship. Subjects were selected for straight profile, mild or moderate crowding in maxillary teeth and normal or mild crowding in mandibular teeth. Nonextraction and Invisalign-aided molar distalization were planned for treatment. Model measurement and cephalometric analysis were performed before and after treatment. A paired t test was used for the statistical analysis.@*Results@#The crowding and class Ⅱ molar relationship were corrected in all 11 patients. The upper first molars were moved distally by 2.32 mm (t = 3.315, P < 0.01) and were inclined distally by 3.35° (t = 3.959, P < 0.01) on average. The central incisors were protruded by 1.72 ° (t = 3.274, P < 0.01) on average. The buccal movement of the upper first molars was 1.32 mm (t = 2.461, P < 0.05) on average. The above differences were statistically significant. @*Conclusion @#Upper molar distalization can be achieved using a class Ⅱ elastic-aided Invisalign technique. The end-to-end molar occlusion can be corrected, and front teeth with mild or moderate crowding can be aligned using our treatment protocol.

Immediate changes in the mandibular dentition after maxillary molar distalization using headgear / 대한치과교정학회지

The purpose of this study was to investigate immediate changes in the mandibular dentition after maxillary molar distalization using headgear in non-growing patients. Sixteen patients (mean age, 18.9 ± 2.0 years) with Class II molar relationship and crowding were included in the present study. To correct the molar relationship, headgear was used for maxillary molar distalization. Cone-beam computed tomography-generated half-cephalograms (CG Cephs) and dental casts were used to evaluate dental changes for each subject before and immediately after molar distalization using headgear. The mean duration that subjects wore the headgear was 6.3 months. CG Cephs showed that the first maxillary molars were distalized 4.2 ± 1.6 mm with 9.7°± 6.1° of distal angulation. The intercanine, interpremolar, and intermolar widths of the mandible increased after maxillary molar distalization. The present study's results suggest that maxillary molar distalization using headgear induces a spontaneous response in the untreated mandibular dentition of non-growing patients.

Evaluation of the invisible bracketless appliance on maxillary molar distalization / 实用口腔医学杂志

Objective:To evaluate the clinical effects of invisible bracketless appliance on the upper molar distalization.Methods:15 patients with class Ⅱ malocclusion(at the average age of 25.3 years) were treated by invisible bracketless appliance,the pre and post three-dimensional digital models were superimposed and measured,the effects of molar distalization were analysed.Results:After treatment,the maxillary first molars were distalized by 2.58 mm on both sides.The left and fight second molars were distalized by 2.57 mm and 2.68 mm respectively.Bilateral central incisors were moved mesially by 0.34 mm.There was no significant difference in the horizontal movement of central incisor.But the left and fight first molars were moved buccally by 0.96 mm and 0.97 mm respectively,the left and fight second molars were moved buccally by 1.01 mm and 1.11 mm separately.Bilateral first molars were intruded by 0.26 mm,the left and right second molars were intruded by 0.37 mm and 0.36 mm,respectively.But the central incisors had no significant vertical movement.There was no significant difference in the buccally or palatally rotation of bilateral first and second molars.Conclusion:Invisible bracketless appliance is efficient for distalization of upper molar,but it may result in mild molar intrusion and anterior anchorage loss.

Distalización de molares maxilares utilizando dispositivos de anclaje esqueletal directo en pacientes con maloclusiones Clase II. Revisión bibliográfica

Introducción: La relación molar de Clase II de Angle se encuentra aproximadamente en un 20% de la población. Cuando la maloclusión es de origen dentario, generada principalmente por una migración de los segmentos laterales, la opción de tratamiento más frecuente para generar espacio y establecer una relación molar de Clase I, es la distalización molar. Un gran número de aparatos y protocolos de tratamiento se han descrito en la literatura. Uno de los más utilizados es el Péndulo, pero debido a su diseño que utiliza anclaje dentario, y a que su fuerza pasa a nivel de la corona de los primeros molares, presenta muchas desventajas. Objetivo: El propósito de esta revisión es analizar los dispositivos de distalización molar que utilizan anclaje esqueletal directo, en los que la fuerza aplicada pasa cerca del centro de resistencia del primer molar superior, con el objetivo de determinar si son superiores en cuanto a eficiencia y minimización de los efectos adversos, cuando se compara con los aparatos convencionales. Resultado: De un total de 25 artículos seleccionados con base en el año de publicación y el empleo de anclaje esqueletal, se utilizaron 7 artículos para revisión, basados en criterios de inclusión y exclusión. Discusión: Al comparar los aparatos, se observa gran variabilidad en duración de tratamiento, cantidad y tasa de distalización. A pesar de estas diferencias todos mostraron éxito clínico el finalizar la mecánica de distalización. Por otra parte, existe una distalización espontánea de los segundos premolares superiores e incluso de los primeros premolares, pero con estos dispositivos que no utilizan estas piezas dentarias como anclaje y que, por lo tanto, quedan libres y son distalizados con la ayuda de las fibras transeptales. Conclusión: Se concluye que la distalización molar ha demostrado ser un procedimiento eficaz cuando se utilizan aparatos con anclaje esqueletal directo y con un vector de fuerza que pase cerca del centro de resistencia de los primeros molares. Estos métodos no generan efectos secundarios en la región de anclaje cuando se compara con aparatos convencionales, donde existen migración mesial de premolares y piezas anteriores. En todos los casos analizados los molares superiores se distalizaron a una relación de clase I en un corto período , incluso a pesar de la presencia de los segundos y terceros molares maxilares.

Introduction: The Angle Class II molar ratio is approximately 20% of the population. When malocclusion is of dental origin, mainly generated by a migration of lateral segments, the most frequent treatment option to generate space and to establish a Class I molar relationship is molar distalization. A large number of treatment devices and protocols have been described in the literature. One of the most used is the Pendulum, but because of its design that uses dental anchorage and its force happens at the level of the crown of the first molars, presents many disadvantages. Objective: The purpose of this review is to analyze molar distalization devices using direct skeletal anchors, in which the applied force passes near the center of resistance of the upper first molar, in order to determine if they are superior in efficiency and minimization of adverse effects when compared with conventional appliances. Results: The search process included a total of 25 articles selected based on year of publication and use of skeletal anchorage, 7 articles were finally used for review, based on inclusion and exclusion criteria. Discussion: When comparing the devices, there is great variability in duration of treatment, amount of distalization and rate of distalization. In spite of these differences all showed clinical success to finalize the mechanics of distalization. On the other hand, here is a spontaneous distalization of the second upper premolars and even the first premolars with these devices that do not use these dental pieces as an anchorage, therefore, they remain free and are distalized with the help of the transseptal fibers. Conclusion: It is concluded that molar distalization has proved to be an effective procedure when using devices with direct skeletal anchors and with a force vector passing close to the resistance center of the first molars. These methods do not generate side effects in the anchoring region when compared to conventional apparatus where there is mesial migration of premolars and anterior parts. In all the cases analyzed, the maxillary molars were distalized to a class I relationship in a short period of time, even in spite of the presence of the second and third maxillary molars.

Treatment of an adult patient with skeletal crossbite and mandibular deviation by distalization of the mandibu-lar molar / 实用口腔医学杂志

An adult patient with skeletal crossbite and mandibular deviation was treated by mandibular molar distalization using micro-im-plant and intermaxillary traction.After treatment,the facial contour of the patient was improved,the Class Ⅰ molar and cuspid relationship was achieved.

Comparison of transverse dental changes induced by the palatally applied Frog appliance and buccally applied Karad's integrated distalizing system / 대한치과교정학회지

OBJECTIVE: To compare the transverse dental changes induced by the palatally applied Frog appliance and buccally applied Karad's integrated distalizing system (KIDS). METHODS: We evaluated the pre- and post distalization orthodontic models of 39 patients, including 19 treated using the Frog appliance, which is palatally positioned (Frog group), and 20 treated using KIDS, which is buccally positioned (KIDS group). Changes in intermolar and interpremolar distances and the amount of maxillary premolar and molar rotation were evaluated on model photocopies. Wilcoxon and Mann-Whitney U tests were used for statistical evaluations. A p-value of < 0.05 was considered statistically significant. RESULTS: Significant distopalatal rotation of premolars and distobuccal rotation of molars were observed in Frog group (p < 0.05), while significant distopalatal rotation of molars (p < 0.05), with no significant changes in premolars, was observed in KIDS group. The amount of second premolar and first molar rotation was significantly different between the two groups (p < 0.05 and p < 0.001, respectively). Furthermore, expansion in the region of the first molars and second premolars was significantly greater in KIDS group than in Frog group (p < 0.001 for both). CONCLUSIONS: Our results suggest that the type and amount of first molar rotation and expansion vary with the design of the distalization appliance used.

Changes produced by the pendulum appliance with skeletal anchorage and comparison with conventional pendulum appliance / Alterações produzidas com o aparelho pêndulo com ancoragem esquelética e comparação com o aparelho pêndulo convencional

Os propósitos destas pesquisas foram primeiramente avaliar as alterações esqueléticas, dento-alveolares e tegumentares obtidas com o aparelho pêndulo com ancoragem esquelética (BAPA) em pacientes com má oclusão Classe II e, posteriormente compará-los com os efeitos produzidos com o aparelho pêndulo com ancoragem convencional (CPA). A amostra composta de 18 pacientes (14 meninas;4 meninos) com idade média de 14.01 (D.P. 1.08) com má oclusão de Classe II tratados com BAPA como dispositivo distalizador antes do aparelho fixo, no Departamento de Ortodontia da Faculdade de Odontologia da Universidade Cidade de São Paulo. Telerradiografias laterais foram tomadas no início do tratamento (T0) e no final da distalização (T1), mensuradas e posteriormente analisadas estatisticamente. Apenas o período da distalização ativa foi avaliado. O grupo controle foi composto de 18 pacientes (14 meninas;4 meninos) com idade média de 13.61 (D.P. 1.24) com a mesma má oclusão tratados com CPA como dispositivo distalizador antes do aparelho fixo, no Departamento de Ortodontia da Faculdade de Odontologia de Bauru, Universidade de São Paulo. Para avaliar os efeitos desta amostra foi utilizada a mesma metodologia acima mencionada. Posteriormente, para comparar as alterações entre os grupos, a amostra tratada com CPA foi denominada Grupo 1 (G1), e a amostra tratada com BAPA denominada Grupo 2 (G2). O tempo médio de distalização foi 5.76 e 6.16 meses, no G1 e G2 respectivamente. Ambos os grupos foram compatibilizados em relação à idade inicial, tempo de tratamento, severidade da má oclusão de Classe II e características cefalométricas iniciais. A comparação intra-grupo foi realizada com teste t dependente, e a comparação intergrupos foi realizada com o teste t. Em G2 houve aumento significante da altura facial anteroinferior, distalização molar, inclinação distal e intrusão significante dos primeiros e segundos molares superiores. Os primeiros pré-molares apresentaram distalização e extrusão significantes. A sobremordida diminuiu e a relação molar melhoraram significativamente. Comparando as alterações do tratamento entre grupos, foram significativamente maiores a distalização, inclinação distal e intrusão dos primeiros molares no G2 comparados ao G1. Os incisivos superiores inclinaram para vestibular no G1, e ligeiramente retroinclinaram para lingual no G2, além disso os primeiros pré-molares foram distalizados no G2, porém foram mesializados no G1. O Grupo 1 apresentou aumento significativamente maior da sobressaliência, e menor correção da relação molar de Classe II do que G2. A distalização dos molares superiores foi obtida com sucesso em ambos os grupos, entretanto, utilizando o BAPA observou-se várias vantagens, tais como: Distalização exclusiva dos molares superiores; movimento distal espontâneo dos pré-molares superiores; sem efeitos colaterais indesejáveis nos incisivos superiores e nos lábios; e também o estabelecimento de uma relação molar de Classe I.(AU)

The purposes of these investigations were firstly to evaluate the dentoalveolar, skeletal and soft tissue effects obtained with the bone-anchored pendulum appliance (BAPA) in patients with Class II malocclusion and secondly, to compare these effects with the conventional pendulum appliance (CPA). A sample of 18 patients (14 females; 4 males) with a mean age of 14.01 years (S.D 1.08) with Class II malocclusion treated with BAPA as distalizer device before fixed appliance in Orthodontic Department at the Dental School, University of São Paulo City. Lateral headfilms were taken at the beginning of treatment (T0) and at the end of distalization period (T1), measured and then statistically analyzed. Only the active distalization period was evaluated. The comparison group was composed by 18 patients (14 females; 4 males) with a mean age of 13.61 years (S.D 1.24) with the same malocclusion treated with CPA before fixed appliance in Orthodontic Department at Bauru Dental School, University of São Paulo. To evaluate the effects in this sample was used the same methodology abovementioned. Then, to compare changes between groups, the sample treated with CPA was named Group 1 (G1), and the sample treated with BAPA was named Group 2 (G2). The average distalization period was 5.76 and 6.16 months, respectively for G1 and G2. Both groups were compatibilized regarding initial age, treatment time, severity of Class II malocclusion and initial cephalometric characteristics. Intragroup comparisons were performed using dependent t tests and intergroup comparisons were performed using t tests. In G2 there was significant increase in the lower anterior face height, molar distalization, distal tipping and intrusion of the first and second maxillary molars. The first premolars had significant distalization and extrusion. Overbite significantly decreased and molar relationship was significantly improved. Comparing the groups, there were significantly greater maxillary first molar distalization, distal tipping and intrusion in G2 compared to G1. The maxillary incisors were labially tipped in G1 and lingually tipped in G2. The first premolars were distalized in G2 while were mesialized in G1. G1 showed a significantly greater overjet increase and smaller Class II molar relationship correction than G2. Distalization of the maxillary molars was successfully achieved in both groups, but using the BAPA several advantages were observed including exclusive maxillary molars distalization, spontaneous distal movement of the maxillary premolars, no undesirable side effects in the maxillary incisors and lips and establishment of a Class I molar relationship.(AU)

Comparative evaluation of molar distalization therapy using pendulum and distal screw appliances / 대한치과교정학회지

OBJECTIVE: To compare dentoalveolar and skeletal changes produced by the pendulum appliance (PA) and the distal screw appliance (DS) in Class II patients. METHODS: Forty-three patients (19 men, 24 women) with Class II malocclusion were retrospectively selected for the study. Twenty-four patients (mean age, 12.2 +/- 1.5 years) were treated with the PA, and 19 patients (mean age, 11.3 +/- 1.9 years) were treated with the DS. The mean distalization time was 7 months for the PA group and 9 months for the DS group. Lateral cephalograms were obtained at T1, before treatment, and at T2, the end of distalization. A Mann-Whitney U test was used for statistical comparisons of the two groups between T1 and T2. RESULTS: PA and DS were equally effective in distalizing maxillary molars (4.7 mm and 4.2 mm, respectively) between T1 and T2; however, the maxillary first molars showed less distal tipping in the DS group than in the PA group (3.2degrees vs. 9.0degrees, respectively). Moreover, significant premolar anchorage loss (2.7 mm) and incisor proclination (5.0degrees) were noted in the PA group, whereas premolar distal movement (1.9 mm) and no significant changes at the incisor (0.1degrees) were observed in the DS group. No significant sagittal or vertical skeletal changes were detected between the two groups during the distalization phase. CONCLUSIONS: PA and DS seem to be equally effective in distalizing maxillary molars; however, greater distal molar tipping and premolar anchorage loss can be expected using PA.

Comparison of the Effects of Modified Jones Device and Face Bow in Molar Distalization / 昆明医科大学学报

Objective To explore the clinical effects of modified Jones device and face bow in molar distalization.Methods 18 patients with mild-to-moderate Angle classⅡmalocclusion caused by crowded front teeth were selected in this study,and they could be treated by tooth extraction or non- extraction correction. The selected patients were randomly divided into two groups,and were treated by molar distalization with modified Jones device and face bow,respectively. X-ray cephalometric and model measurement was performed in patients in two groups before and after treatment.Result Both modified Jones device and face bow had obvious effects in molar distalization, but had statistically significant differences in the molar moving speed, anterior overjet and the inclination of the first molar.Conclusions Both methods can effectively push the maxillary molar to far,but face bow method needs good cooperation of patients and can't continue to work,so the clinical curative effect is not very stable. By modified Jones device can more quickly and effectively promote maxillary molar move far,and does not depend on the patient's coordination,so it is worth clinical popularizing.

Comparison of two position implant-supported molar distalization systems / 实用口腔医学杂志

Objective:To compare 2 position implant-supported molar distalization systems in clinical application.Methods:25 pa-tients with Class II and mild to moderate crowding dentition were included,18 females and 7 males,aged 15 to 29 years old(22.58 on average ).All the patients were treated with non-extraction method by distalizing the upper molar with micro-implant anchorage.In ex-perimental group(n =12)the micro-implants were inserted on infrazygomatic crest above the maxillary first molar mesial buccal root. In control group(n =13)the micro-implants were inserted on buccal alveolar bone between maxillary second premolar and maxillary first molar.In both groups micro-implants were inserted to distalize the maxillary molars.The displacement patterns of maxillary inci-sors and molars were measured and compared.Results:Successful primary micro-implant placement was obtained in 87.5%(21 /24) of the implantation in control group and 100%(26 /26)in experimental group.The distal movement(mm)of the molars in control and experiment group was 2.29 ±0.96 and 2.91 ±0.96 respectively(P >0.05).Experimental group showed significant intrusive displace-ment of the molars.Horizontal incisor displacement in experimental group was more than that in control group.Conclusion:Micro-im-plant inserted in infrazygomatic crest may facilitate intrusion and distalization of the maxillary molar and incisor.

Combined treatment with headgear and the Frog appliance for maxillary molar distalization: a randomized controlled trial / 대한치과교정학회지

OBJECTIVE: To evaluate the efficiency of the Frog appliance (FA) alone or in combination with headgear for distalizing the maxillary molars. METHODS: Fifty patients (25 males and 25 females) aged 12.6 - 16.7 years who received treatment for Class II malocclusion at the Orthodontic Clinic of Al-Baath University were selected for this study and randomly divided into 2 equal groups. Maxillary molar distalization was achieved using the FA alone (group 1) or a combination of the FA with high-pull headgear worn at night (group 2). Lateral cephalograms were obtained before and after treatment. RESULTS: The maxillary molars moved distally by 5.51 and 5.93 mm in groups 1 and 2, respectively. Distal movements were associated with axial tipping by 4.96degrees and 1.25degrees, and with loss of anchorage by mesial movement of the second maxillary premolars by 2.70 and 0.90 mm in groups 1 and 2, respectively. The combined use of the FA and nighttime high-pull headgear decreased the distalization time and improved the ratio of maxillary molar distalization movement relative to the overall opening space between the first maxillary molars and second premolars. CONCLUSIONS: The FA can effectively distalize the maxillary molars, this distalization associates with some unfavorable changes. Nighttime use of high-pull headgear combined with the FA can reduce these unfavorable changes and improve treatment outcomes.

Combined treatment with headgear and the Frog appliance for maxillary molar distalization: a randomized controlled trial / 대한치과교정학회지

OBJECTIVE: To evaluate the efficiency of the Frog appliance (FA) alone or in combination with headgear for distalizing the maxillary molars. METHODS: Fifty patients (25 males and 25 females) aged 12.6 - 16.7 years who received treatment for Class II malocclusion at the Orthodontic Clinic of Al-Baath University were selected for this study and randomly divided into 2 equal groups. Maxillary molar distalization was achieved using the FA alone (group 1) or a combination of the FA with high-pull headgear worn at night (group 2). Lateral cephalograms were obtained before and after treatment. RESULTS: The maxillary molars moved distally by 5.51 and 5.93 mm in groups 1 and 2, respectively. Distal movements were associated with axial tipping by 4.96degrees and 1.25degrees, and with loss of anchorage by mesial movement of the second maxillary premolars by 2.70 and 0.90 mm in groups 1 and 2, respectively. The combined use of the FA and nighttime high-pull headgear decreased the distalization time and improved the ratio of maxillary molar distalization movement relative to the overall opening space between the first maxillary molars and second premolars. CONCLUSIONS: The FA can effectively distalize the maxillary molars, this distalization associates with some unfavorable changes. Nighttime use of high-pull headgear combined with the FA can reduce these unfavorable changes and improve treatment outcomes.

Molar Distalisation By Palatal Implants- A Case Report.

Palatal implants have been used to establ ish stat ionary anchorage. The stability of a palatal implant for distalization of molars bodily and for anchorage maintenance was assessed. The implant was a stepped screw titanium (4.5 mm diameter x 8.5 mm length), and it was placed in the palatal region. A surgical template containing a metal drill housing was prepared. Angulation of the drill housing was controlled according to the radiologic tracing of the maxilla transferred to a plaster cast section in the paramedian plane. The implant was placed using a noninvasive technique and left transmucosally to facilitate the surgical procedure and to reduce the number of operations. The paramedian region was selected (1) to avoid the connective tissues of the palatine suture and (2) because it is considered to be a suitable host site for implant placement. After three months of healing, the implant was osseointegrated and orthodontic treatment was initiated. The results showed that the molars were distalized bodily at five months, and no anchorage loss was observed. At the end of the treatment, the smile was improved, and an ideal Class I molar and canine relationship, an ideal overbite, and an ideal overjet were all achieved. In conclusion, palatal implants can be used effectively for anchorage maintenance and in space-gaining procedures. Use of a three-dimensional surgical template eliminated implant placement errors, reduced chair time, minimized trauma to the tissues, and enhanced osseointegration. This method can be used effectively to achieve distalization of molars bodily without anchorage loss.

Distalização de segundo molar inferior impactado através da utilização de ancoragem esquelética com miniplaca: relato de caso / Distalization of impacted mandibular second molar using miniplates for skeletal anchorage: case report

O presente estudo consiste no relato de um caso onde a distalização do segundo molar inferior impactado do lado direito foi obtida através da ancoragem esquelética com o uso de miniplaca. A verticalização dos segundos molares inferiores impactados, durante muito tempo, colocou-se como um grande desafio para ortodontistas e cirurgiões bucais devido à escassez de recursos de ancoragem destinados para esse fim. A utilização da ancoragem esquelética foi iniciada na clínica ortodôntica em meados dos anos 80 e, desde então, diversas modalidades têm sido desenvolvidas para esse princípio, como a utilização de mini-implantes, implantes dentários e, finalmente, miniplacas, que foram testadas e apresentaram resultados animadores. O assunto é relevante para ortodontistas e cirurgiões bucais, uma vez que o uso das miniplacas pode influir de forma significativa no tratamento de molares inferiores impactados.

This study describes a case with an impacted right mandibular second molar which was distalized using miniplates for skeletal anchorage. Uprighting impacted mandibular second molars has been a great challenge for orthodontists and oral surgeons because of the scarcity of anchorage options. Skeletal anchorage was first used in clinical orthodontics in the middle of the 1980s. Since then, several devices have been developed for that purpose, such as mini-screws, tooth implants and, lately, miniplates, which have been tested and showed encouraging results. This topic is relevant for orthodontists and oral surgeons because the use of miniplates may significantly change the treatment of impacted mandibular molars.

Noncompliance screw supported maxillary molar distalization in a parallel manner / 대한치과교정학회지

OBJECTIVE: Intraoral noncompliance upper molar distalization techniques have gained in popularity and have subsequently found to be successful in Class II correction. The aim of the present study was to introduce a screw supported intraoral distalization appliance and investigate its efficiency. METHODS: Twenty-one subjects (11 females, 10 males; average age of 14.9 years) with Angle Class II malocclusion participated in this study. Two screws were inserted behind the incisive foramen and immediately loaded to distalize the upper first molars. An intraoral screw supported distalization appliance was used to distalize the upper molars in order to achieve a Class I molar relationship. Skeletal and dental changes were evaluated using cephalometric and three-dimensional (3D) model analysis. RESULTS: Upper molars were distalized 3.95 mm on average and a Class I molar relationship was achieved without any anchorage loss. The upper molars were tipped only 1.49degrees and the upper right and left molars were rotated only 0.54degrees and 0.74degrees respectively which were statistically non-significant (p > 0.05). CONCLUSIONS: The newly designed screw supported noncompliance distalization appliance was found to be an effective device for achieving bodily molar distalization without any anchorage loss.

Distal jet modification: an option in distalization / Modificación del distal jet: una opción en distalización

The objective of the present study was to describe how a distalizer can be made so that some failures existing in these devices can also be eliminated. Because such devices are easy to make and have a low cost, they are becoming a viable option for treating Class II malocclusions without extraction regardless of the patient’s co-operation.

El objetivo del presente estudio fue describir cómo un distalizador puede ser hecho de modo que algunos fracasos existentes en estos dispositivos también pueden ser eliminados. Debido a que estos dispositivos son fáciles de hacer y tienen un bajo costo, se están convirtiendo en una opción viable para el tratamiento de pacientes con maloclusiones clase II sin extracción independientemente de su cooperación.