MARPE Guide: A Case Report.

AIM: This paper presents a prototyped surgical guide for placement of MARPE-mini-implant-assisted rapid palatal expander. BACKGROUND: Investigations conducted in the last decades have increased the technological resources used in orthodontics. This scientific advance applies to several clinical procedures, including the planning of devices used in guided surgeries, using computed tomography images and intraoral scanning. CASE DESCRIPTION: This case report presents maxillary expansion in an adult patient (18 years and 5 months), using the MARPE technique, by virtual planning and fabrication of a surgical guide (laser-printed on a 3D printer MoonRay D225-SprintRay, 2014), after merging of 3 files: digital file of the expander (.stl), computed tomography of the suture, and intraoral scanning of the patient, using the planning software NemoStudio (version 20122, 16.50.0.56). CONCLUSION: Fabrication of a surgical guide for the MARPE technique provides an accurate transfer of the virtual planning to the surgical procedure. It allows three-dimensional orientation of the expander position and perforations of mini-implants, which are necessary to establish anchorage in areas with sufficient bone, assuring the system stability and a successful procedure. CLINICAL SIGNIFICANCE: The mini-implant assisted rapid palatal expansion (MARPE) has been investigated as a promising option for correction of malocclusion related with maxillary atresia in adult patients and is an option to orthognathic surgery. Digital treatment planning is fundamental to establish individual, reproducible, and accurate parameters, as in the present case, which evidenced significant benefits in both occlusal and respiratory aspects.

Tooth movement rate and anchorage lost during canine retraction: A maxillary and mandibular comparison.

OBJECTIVES: To investigate the canine retraction rate and anchorage loss during canine retraction using self-ligating (SL) brackets and conventional (CV) brackets. Differences between maxillary and mandibular rates were computed. MATERIALS AND METHODS: Twenty-five subjects requiring four first premolar extractions were enrolled in this split-mouth, randomized clinical trial. Each patient had one upper canine and one lower canine bonded randomly with SL brackets and the other canines with CV brackets but never on the same side. NiTi retraction springs were used to retract canines (100 g force). Maxillary and mandibular superimpositions, using cephalometric 45° oblique radiographs at the beginning and at the end of canine retraction, were used to calculate the changes and rates during canine retraction. Paired t-tests were used to compare side and jaw effects. RESULTS: The SL and CV brackets did not show differences related to monthly canine movement in the maxilla (0.71 mm and 0.72 mm, respectively) or in the mandible (0.54 mm and 0.60 mm, respectively). Rates of anchorage loss in the maxilla and in the mandible also did not show differences between the SL and CV brackets. Maxillary canines showed greater amount of tooth movement per month than mandibular canines (0.71 mm and 0.57 mm, respectively). CONCLUSIONS: SL brackets did not show faster canine retraction compared with CV brackets nor less anchorage loss. The maxillary canines showed a greater rate of tooth movement than the mandibular canines; however, no difference in anchorage loss between the maxillary and mandibular posterior segments during canine retraction was found.

Dental skeletal effects of the metallic splinted Herbst appliance after growth spurt: a lateral oblique cephalometric assessment.

The aim of this study was to evaluate dental and skeletal changes induced by the use of Herbst appliance compared to natural growth in young adults with Class II division I malocclusion with mandibular retrusion, by means of lateral oblique radiographs. Forty-six subjects, I4 -18 years old, after pubertal growth peak, with Class II division I malocclusion were assessed. Subjects were divided into two groups: the Experimental group included 23 subjects treated with Metallic Splinted Herbst and the Control group included 23 subjects followed without treatment. The Experimental and Control groups were paired by sex and chronological age. Oblique lateral cephalometric radiographs of the left and the right side of the mandible before treatment (TI) and after 8 months' treatment (T2) were used to evaluate dental and skeletal changes. Statistical analysis was performed with Intra Class Correlation and Student t-test, according to the study hypothesis. The results showed that the appliance corrected the Class II relationship in an 8-month period by mesial tipping movement of lower permanent first molars. It had little influence on mandibular structure and mandibular length and no influence on maxillary structure and upper molar. To conclude, late treatment of Class II malocclusion with the Herbst appliance was accomplished by means of dentoalveolar changes. These findings suggest that this type of treatment can be used in patients after growth has ceased because the results do not depend upon skeletal changes.

O objetivo é avaliar mudanzas dento esqueléticas induzidas pelo uso do aparelho de Herbst considerando crescimento natural através da telerradiografía cefalométrica em 45o em adultos jovens com Classe II divisao 1 e retrusao mandibular. Uma amostra de 46 individuos com idade entre 14 a 18 anos, após surto de crescimentopubertário, Classe II divisao 1 foram avaliados e divididos em dois grupos: grupo Experimental, 23 individuos que foram tratados com Herbst splint metálico e grupo Controle, 23 individuos que foram acompanhados sem tratamento. Os grupos experimental e Controle foram pareados por genero e idade cronológica. Foram usadas telerradiografias cefalométrica em 45o dos lados esquerdo e direito da mandíbula antes do tratamento (T1) e após periodo de 8 meses de tratamento e seguinte (T2) para avaliar as mudanzas dento esqueléticas. Análise estatistica foi realizada com o indice de Correlagao Intra Classe e teste t de Student de acordo com a hipótese do estudo. Os resultados mostraram que houve corregaoda relagao de Classe II no periodo de 8 meses por movimento mesial do primeiro molar inferior. O aparelho teve pequena influencia na estrutura mandibular e compri-mento mandibular e nenhuma influencia na estrutura maxilar e molar superior. Em conclusao, o tratamento tardio da má-oclusao de Classe II com o aparelho MESPHER foi alcangado através de mudangas dento alveolares.

Dental skeletal effects of the metallic splinted Herbst appliance after growth spurt: a lateral oblique cephalometric assessment / Efeitos dentoesqueléticos do aparelho splint metálico de Herbst apóssurto de crescimento: estudo com telerradiografias em 45o

The aim of this study was to evaluate dental and skeletal changes induced by the use of Herbst appliance compared to natural growth in young adults with Class II division 1 malocclusion with mandibular retrusion, by means of lateral oblique radiographs. Fortysix subjects, 14 18 years old, after pubertal growth peak, with Class II division 1 malocclusion were assessed. Subjects were divided into two groups: the Experimental group included 23 subjects treated with Metallic Splinted Herbst and the Control group included 23 subjects followed without treatment. The Experimental and Control groups were paired by sex and chronological age. Oblique lateral cephalometric radiographs of the left and the right side of the mandible before treatment (T1) and after 8 months' treatment (T2) were used to evaluate dental and skeletal changes. Statistical analysis was performed with Intra Class Correlation and Student ttest, according to the study hypothesis. The results showed that the appliance corrected the Class II relationship in an 8month period by mesial tipping movement of lower permanent first molars. It had little influence on mandibular structure and mandibular length and no influence on maxillary structure and upper molar. To conclude, late treatment of Class II malocclusion with the Herbst appliance was accomplished by means of dentoalveolar changes. These findings suggest that this type of treatment can be used in patients after growth has ceased because the results do not depend upon skeletal changes (AU)

O objetivo é avaliar mudanças dento esqueléticas induzidas pelo uso do aparelho de Herbst considerando crescimento natural através da telerradiografia cefalométrica em 45o em adultos jovens com Classe II divisão 1 e retrusão mandibular. Uma amostra de 46 indivíduos com idade entre 14 a 18 anos, após surto de crescimento pubertário, Classe II divisão 1 foram avaliados e divididos em dois grupos: grupo Experimental, 23 indivíduos que foram tratados com Herbst splint metálico e grupo Controle, 23 indivíduos que foram acompanhados sem tratamento. Os grupos experimental e Controle foram pareados por gênero e idade cronológica. Foram usadas telerradiografias cefalométrica em 45o dos lados esquerdo e direito da mandíbula antes do tratamento (T1) e após período de 8 meses de tratamento e seguinte (T2) para avaliar as mudanças dento esqueléticas. Análise estatística foi realizada com o índice de Correlação Intra Classe e teste t de Student de acordo com a hipótese do estudo. Os resultados mostraram que houve correçãoda relação de Classe II no período de 8 meses por movimento mesial do primeiro molar inferior. O aparelho teve pequena influencia na estrutura mandibular e compri mento mandibular e nenhuma influência na estrutura maxilar e molar superior. Em conclusão,o tratamento tardio da máoclusão de Classe II com o aparelho MESPHER foi alcançado através de mudanças dento alveolares (AU)