Accuracy of arch expansion with two thermoplastic materials in Invisalign® patients: EX30® and SmartTrack®.

OBJECTIVE: The purpose of this retrospective study was to compare accuracy of arch expansion using two different thermoplastic materials in Invisalign aligners: EX30® (Polyethylene Terephthalate Glycol, or PETG) and SmartTrack® (polyurethane). METHODS: The study sample comprised 65 adult patients consecutively treated with Invisalign from two private practices: group 1 - treated with EX30® (358 teeth) and group 2 - treated with SmartTrack® (888 teeth). Six hundred and twenty-three measurements were assessed in three digital models throughout treatment: model 1 - initial, model 2 - predicted tooth position, and model 3 - achieved position. Sixteen reference points per arch were marked and, after best alignment, 2 points per tooth were copied from one digital model to another. Linear values of both arches were measured for canines, premolars, and first molars: on lingual gingival margins and cusp tips of every tooth. Comparisons were performed by Wilcoxon and Mann-Whitney test. RESULTS: Both termoplastic materials presented significant differences between predicted and achieved values for all measurements, except for the lower molar cusp tip in the SmartTrack® group. There is no statistical difference in the accuracy of transverse expansion between these two materials. Overall accuracy for EX30® aligners in maxilla and mandible were found to be 37 and 38%, respectively; and Smarttrack® presented an overall accuracy of 56.62% in the maxilla and 68.72% in the mandible. CONCLUSIONS: It is not possible to affirm one material expands better than the other. Further controlled clinical studies should be conducted comparing SmartTrack® and EX30® under similar conditions.

Accuracy of Invisalign® aligners in adult patients: a retrospective study of angular tooth movements.

OBJECTIVE: This retrospective study aimed to assess the predictability of Invisalign® aligners regarding rotational, mesio-distal and buccal-lingual tip movements. METHODS: Two materials were included in the analysis - EX30, used until 2013; and SmartTrack, in current use. The study comprised 56 adult patients treated with Invisalign Comprehensive. Data sample were assessed on three sets of digital models; model 1 - initial, model 2 - predicted, and model 3 - achieved. Sixty reference points were marked in each dental arch, and two reference planes assisted the superimposition. The degree of rotation, mesio-distal and buccal-lingual tip was obtained via trigonometric calculations, through a previously published validated method. The accuracy of outcomes was compared according to the types of tooth movement and teeth groups,and the influence of predetermined variables on movement accuracy was also investigated. RESULTS: Rotation and mesio-distal tip did not present any significant difference when comparing EX30 and SmartTrack groups. Only buccal-lingual tip presented a significant difference, incisor and canine groups treated with EX30 aligners presented an increase in accuracy (p= 0.007 and p = 0.007, respectively). For each additional degree planned for rotation movements, there was an increase of 0.35° in the discrepancy, and an increase of 0.40° and 0.41° for mesio-distal and buccal-lingual tip, respectively. EX30 and SmartTrack discrepancies were compared by multilevel linear regression. CONCLUSION: EX30 aligners reached higher accuracy for buccal-lingual tip in anterior teeth. However, for rotation and mesio-distal tip, SmartTrack and EX30 are similarly accurate. The total amount of planned movement has a significant impact on accuracy rates, with a decrease in accuracy for every additional degree.

Accuracy of arch expansion with two thermoplastic materials in Invisalign® patients: EX30® and SmartTrack®

ABSTRACT Objective: The purpose of this retrospective study was to compare accuracy of arch expansion using two different thermoplastic materials in Invisalign aligners: EX30® (Polyethylene Terephthalate Glycol, or PETG) and SmartTrack® (polyurethane). Methods: The study sample comprised 65 adult patients consecutively treated with Invisalign from two private practices: group 1 - treated with EX30® (358 teeth) and group 2 - treated with SmartTrack® (888 teeth). Six hundred and twenty-three measurements were assessed in three digital models throughout treatment: model 1 - initial, model 2 - predicted tooth position, and model 3 - achieved position. Sixteen reference points per arch were marked and, after best alignment, 2 points per tooth were copied from one digital model to another. Linear values of both arches were measured for canines, premolars, and first molars: on lingual gingival margins and cusp tips of every tooth. Comparisons were performed by Wilcoxon and Mann-Whitney test. Results: Both termoplastic materials presented significant differences between predicted and achieved values for all measurements, except for the lower molar cusp tip in the SmartTrack® group. There is no statistical difference in the accuracy of transverse expansion between these two materials. Overall accuracy for EX30® aligners in maxilla and mandible were found to be 37 and 38%, respectively; and Smarttrack® presented an overall accuracy of 56.62% in the maxilla and 68.72% in the mandible. Conclusions: It is not possible to affirm one material expands better than the other. Further controlled clinical studies should be conducted comparing SmartTrack® and EX30® under similar conditions.

RESUMO Objetivo: O objetivo deste estudo retrospectivo foi comparar a acurácia na expansão da arcada utilizando alinhadores Invisalign com dois tipos de material termoplástico: EX30® (Polietileno Tereftalato Glicol, ou PETG) e SmartTrack® (poliuretano). Método: A amostra desse estudo incluiu 65 pacientes adultos tratados consecutivamente em dois consultórios particulares: grupo 1 - tratado com EX30® (358 dentes), e grupo 2 - tratado com SmartTrack® (888 dentes). Foram avaliadas 623 medidas em três pares de modelos digitais, ao longo do tratamento: modelo 1 - inicial, modelo 2 - posição dentária planejada, modelo 3 - posição alcançada. Foram marcados 16 pontos de referência por arcada e, após o bestfit, 2 pontos por arcada foram copiados de um modelo digital para o outro. Medidas lineares de ambas as arcadas foram aferidas para caninos, pré-molares e primeiros molares, localizadas na margem gengival lingual e ponta de cúspide de todos os dentes. Foram realizadas comparações usando os testes Wilcoxon e Mann-Whitney. Resultados: Ambos os materiais termoplásticos apresentaram diferenças significativas entre os valores planejados e alcançados em todas as medidas, exceto na ponta de cúspide dos primeiros molares inferiores do grupo SmartTrack®. Não houve diferença estatística entre esses dois materiais quanto à acurácia da expansão transversa. Em termos gerais, a acurácia dos alinhadores EX30® na maxila e mandíbula foi de 37% e 38%, respectivamente. O grupo SmartTrack® apresentou acurácia de 56,62% e 68,72% na maxila e mandíbula, respectivamente. Conclusões: Não foi possível afirmar que um material expande melhor que o outro. Estudos clínicos controlados futuros devem ser conduzidos comparando SmartTrack® e EX30® sob condições similares.

Accuracy of Invisalign® aligners in adult patients: a retrospective study of angular tooth movements

ABSTRACT Objective: This retrospective study aimed to assess the predictability of Invisalign® aligners regarding rotational, mesio-distal and buccal-lingual tip movements. Methods: Two materials were included in the analysis - EX30, used until 2013; and SmartTrack, in current use. The study comprised 56 adult patients treated with Invisalign Comprehensive. Data sample were assessed on three sets of digital models; model 1 - initial, model 2 - predicted, and model 3 - achieved. Sixty reference points were marked in each dental arch, and two reference planes assisted the superimposition. The degree of rotation, mesio-distal and buccal-lingual tip was obtained via trigonometric calculations, through a previously published validated method. The accuracy of outcomes was compared according to the types of tooth movement and teeth groups,and the influence of predetermined variables on movement accuracy was also investigated. Results: Rotation and mesio-distal tip did not present any significant difference when comparing EX30 and SmartTrack groups. Only buccal-lingual tip presented a significant difference, incisor and canine groups treated with EX30 aligners presented an increase in accuracy (p= 0.007 and p = 0.007, respectively). For each additional degree planned for rotation movements, there was an increase of 0.35° in the discrepancy, and an increase of 0.40° and 0.41° for mesio-distal and buccal-lingual tip, respectively. EX30 and SmartTrack discrepancies were compared by multilevel linear regression. Conclusion: EX30 aligners reached higher accuracy for buccal-lingual tip in anterior teeth. However, for rotation and mesio-distal tip, SmartTrack and EX30 are similarly accurate. The total amount of planned movement has a significant impact on accuracy rates, with a decrease in accuracy for every additional degree.

RESUMO Objetivo: Esse estudo retrospectivo teve como objetivo aferir a previsibilidade dos alinhadores Invisalign em relação aos movimentos de rotação e inclinações mesiodistal e vestibulolingual. Material e Métodos: Foram incluídos dois materiais nessa análise: EX30®, utilizado até 2013; e SmartTrack®, atualmente em uso. Esse estudo avaliou 56 pacientes tratados com Invisalign Comprehensive. Os dados foram avaliados em três pares de modelos digitais; modelo 1 - inicial, modelo 2 - planejado, e modelo 3 - alcançado. Foram marcados 60 pontos de referência em cada arcada, sendo a sobreposição realizada com auxílio de planos de referência. O grau de rotação e inclinações mesiodistal e vestibulolingual foi obtido por cálculos de trigonometria, usando um método validado publicado anteriormente. Os resultados foram comparados de acordo com os tipos de movimento dentário e grupos de dentes, também foi investigada a influência de variáveis predeterminadas na confiabilidade dos movimentos. Resultados: Os movimentos de rotação e inclinação mesiodistal não apresentaram diferença estatística, quando comparados os grupos EX30® e SmartTrack®. Somente a inclinação vestibulolingual apresentou diferença estatisticamente significativa, sendo que os grupos de incisivos e caninos tratados com alinhadores EX30® apresentaram um aumento na previsibilidade(p= 0,007 e p= 0,007, respectivamente). Para cada grau adicional planejado para movimento de rotação, ocorreu um aumento de 0,35° na discrepância, e aumentos de 0,40° e 0,41° para as inclinações mesiodistal e vestibulolingual, respectivamente. As discrepâncias entre EX30® e SmartTrack® foram comparadas por regressão linear multinível. Conclusão: Os alinhadores EX30® alcançaram maior previsibilidade para a inclinação vestibulolingual em dentes anteriores. No entanto, para rotação e inclinação mesiodistal, SmartTrack® e EX30® apresentaram previsibilidade similar. A quantidade total de movimento planejado apresenta influência significativa nas taxas de previsibilidade, com diminuição na acurácia para cada grau adicional.

Tissue repair after selective alveolar corticotomy in orthodontic patients: A preliminary study.

OBJECTIVES: To analyze histologic findings of bone remodeling at the time of surgery and 90 days later at corticotomized and noncorticotomized sites. MATERIALS AND METHODS: Eight adult patients with bilaterally inclined mandibular molars were included in this split-mouth study. Corticotomy was performed on the test side, and bone was harvested on both mandibular hemi-arches. Bone blocks were shipped to Forsyth Institute lab (Boston, Mass). After surgery, cantilevers were activated to upright inclined mandibular molars on both sides. Approximately 90 days after surgery, new mandibular bone blocks were harvested from test and control sites. Histologic analyses were performed on both groups (test and control sides) at two time points: baseline (T0) and 90 days after surgery (T90). Bone blocks were stained with hematoxylin and eosin, and Masson's trichrome. The protocols enabled screening of new bone formation and collagen in mineralized and nonmineralized connective tissue. Outcomes were compared using a clustered generalized estimating equations model Results: The test group at T90 exhibited an increase of 16% of primary bone ( P < .05), an increase of 6.6 in osteocytes quantity ( P = .039), and an increase of 4.06 in reversal lines quantity ( P = .924). Both groups exhibited a decrease in the inorganic proportion. CONCLUSIONS: The intentional bone injury performed in adult patients undergoing orthodontic treatment can be considered temporary and reversible. Evidence indicates that baseline bone characteristics are unaltered.

Tratamento da assimetria facial causada por hiperplasia condilar: série de casos / Treatment of facial asymmetry caused by condylar hyperplasia: case series

Introdução: a hiperplasia do côndilo (HC) mandibular tem sido descrita como o crescimento excessivo de um dos côndilos sobre o contralateral, causando um crescimento desequilibrado, que resulta em assimetria facial. A classificação e o diagnóstico da HC, a atividade de crescimento dos côndilos, e as formas de tratamento foram abordados no presente estudo. Material e Métodos: foram descritas as formas de tratamento de três pacientes apresentando HC. As soluções cirúrgicas são representadas por condilectomia, cirurgia ortognática, e uma combinação de ambos. Resultados: após a realização do procedimento cirúrgico específico indicado para cada caso, houve melhora significativa na simetria facial e na função mastigatória. Conclusões: o diagnóstico da HC se baseia em achados clínicos e radiológicos, e esses avaliam as consequências do crescimento desproporcional. A cintilografia óssea funciona como um indicador da rapidez da progressão dessa condição, sendo essencial no planejamento cirúrgico do tratamento

Resposta tecidual à corticotomia alveolar seletiva após verticalização ortodôntica acelerada de molares inferiores em pacientes adultos / Tissue response to selective alveolar corticotomy after speedy orthodontics in uprighting lower molars in adult patients

O objetivo deste trabalho foi analisar e descrever histologicamente, o processo de remodelação óssea no momento da cirurgia e 90 dias após, em regiões submetidas ou não à corticotomia alveolar seletiva. Foram avaliados 8 pacientes adultos sem distinção de classe de maloclusão, e com necessidade de verticalização dos segundos molares inferiores bilateralmente. Neste estudo aleatório boca-dividida, a verticalização dos molares inferiores e coleta de osso mandibular aconteceu bilateralmente, enquanto que a corticotomia unilateralmente. As extrações dos blocos ósseos foram obtidas através de uma broca trefina acoplada ao contra ângulo, as peças continham aproximadamente 6 mm de osso cortical e trabecular, e foram armazenadas em formol tamponado a 10% até a data de envio ao laboratório do Instituto Forsyth (Boston, EUA). Após 90 dias da cirurgia, novas biopsias ósseas foram extraídas do segmento mandibular teste e controle. As avaliações histológicas foram realizadas no grupo teste e controle em dois momentos distintos: no momento da corticotomia (T0), e 90 dias após (T90). Os blocos ósseos foram corados com hematoxilina e eosina (HE) para análise descritiva das peças. A coloração com tricrômico de Masson (TM) foi utilizada com o intuito de identificar neoformação óssea e colágeno no tecido conjuntivo mineralizado e não mineralizado. Para descrição da remodelação óssea foram analisadas as seguintes características celulares: proporção entre os componentes de osso secundário e primário, quantificação do número de osteócitos, proporção entre os componentes inorgânicos e orgânicos do osso, e quantificação do número de linhas reversas. Os resultados foram comparados por meio do modelo de estimativa de equações generalizadas (GEE) clusterizado, ajustando pelas medidas basais. O grupo teste em T90 apresentou aumento de 0,16% na proporção de osso primário (p<0,001), aumento de 6,54 na quantidade de osteócitos (p=0,039), e aumento de 4,06 na quantidade de linhas reversas de remodelação óssea (p=0,924). Ambos os grupos apresentaram queda na proporção inorgânica, com um diminuição de 0,02% e 0,03% nos grupos teste e controle, respectivamente (p=0,105). Os dados sugerem que o processo de reabsorção óssea alveolar desencadeado pela corticotomia seja parcialmente revertido em 90 dias, pois foi possível observar características de formação e deposição óssea. O dano ósseo intencional realizado em pacientes adultos tratados ortodônticamente, pode ser considerado temporário e reversível, e as condições ósseas iniciais são restabelecidas.

The aim of this study was to analize and describe histological findings of bone remodeling at the time of surgery and 90 days later, at corticotomized and non-corticotomized sites. This randomized split mouth study included 8 adult patients, with bilaterally inclined mandibular molars, regardless their malocclusion type. A one-stage intervention was performed to corticotomize the test site, and harvest bone in both mandibular hemi-arches. Bone blocks were harvested using a trephine bur in a low speed hand piece. The specimens of aproximatelly 6 mm were stored in 10% buffered formalin at room temperature, until dispatch to Forsyth Institute lab (Boston, USA). After surgery, cantilevers were activated to upright inclined mandibular molars on both sides. Approximately 90 days post-surgery, new bone blocks were harvested from test and control sites located in the mandible. Histological analysis were performed in the control and test group at two time points: baseline (T0) and, ninety days post-surgery (T90). Bone blocks were stained with Hematoxylin & Eosin for descriptive analysis. Masson's trichrome staining protocol was used to identify new bone formation and collagen in mineralized and non-mineralized connective tissue. The following items were investigated to describe bone turnover: (1) ratio between secondary and primary bone, (2) ratio between inorganic and organic bone, (3) quantity of osteocytes and, (4) reversal lines of bone remodeling.The histologic analysis results were compared using clustered Generalized Estimating Equations (GEE) model, adjusted by baseline measures. The test group at T90 presented: increase of 0.16% in ratio of primary bone (p<0.001), increase of 6.54 in the quantity of osteocytes (p=0.039), and increase of 4.06 in the quantity of reversal lines (p=0.924). Both groups presented decay in inorganic proportions, with a decrease of 0.02% and 0.03% in test and control group, respectively (p=0.105). Data suggest that bone turnover provoked by corticotomy, might be partially reverted in 90 days, through bone formation and deposition. The intentional bone injury performed in adult patients undergoing orthodontic treatment, can be considered temporary and reversible, there is evidence to indicate baseline bone characteristics are restored.

Immediate vs late orthodontic extrusion of traumatically intruded teeth.

Although the published papers about this matter is limited to clinical case reports, the aim of this review was to quantify the success rate of immediate vs late orthodontic extrusion of traumatically intruded teeth. From 55 reports in a PubMed and Medline computerized search, 13 reported patients involving 22 traumatically intruded anterior upper teeth with orthodontic extrusion were selected. In the sample of 13 patients, six were males and seven females and the average age was 16.4 years old. The selection criteria were patients presenting traumatized anterior upper teeth resulting in intrusive luxation, with at least 1 year follow-up period. Orthodontic extrusive forces were applied in the immediate group within 10 weeks post-trauma, while in the late group the forces were applied only after 3 months post-trauma. Immediate and late orthodontic extrusion was extremely favorable. The success rate (without or with complications) was 95.4% against only 4.5% (1 tooth) because of inflammatory root resorption with rapid progression. All mature teeth (100%) were endodontically treated. Among the 12 immature traumatically intruded teeth, eight were endodontically treated and four were not. A high rate of success was reported in the literature in traumatically intruded teeth orthodontically extruded, either immediate or late.