Orthodontic traction of impacted maxillary canines using segmented arch mechanics

ABSTRACT The principles of orthodontic mechanics strongly influence the success of impacted canine traction. The present study discusses the main imaging exams used for diagnosis and localization of impacted canines, the possible associated etiological factors and the most indicated mechanical solutions.

RESUMO Os princípios vetoriais da mecânica ortodôntica têm influência direta no sucesso do tracionamento dos caninos impactados. O objetivo desse artigo é discorrer sobre os possíveis fatores etiológicos associados à impacção dos caninos, os exames de imagem indicados no processo de diagnóstico e localização das unidades retidas, e as melhores soluções mecânicas para o tracionamento desses dentes.

Why canines induce resorption of neighboring roots? An imaging correlation

ABSTRACT Despite the explanations about the mechanisms and reasons why dental follicles of unerupted maxillary canines do not cause root resorption in neighboring teeth, questions remain about the time expected for this event and the lack of protocols for preventive clinical management, which may serve as insights for further studies. Here, these mechanisms are correlated with imaging findings of CT scans and 3D reconstructions of a typical clinical case.

RESUMO Apesar das explicações dos mecanismos e dos porquês os folículos pericoronários dos caninos superiores não irrompidos podem reabsorver as raízes dos dentes vizinhos, questiona-se a inexistência de previsibilidade do tempo em que isso ocorre e a ausência de protocolos de condutas clínicas preventivas, como insights para novas pesquisas. Correlaciona-se, também, esses mecanismos com os aspectos imaginológicos de cortes tomográficos e reconstruções 3D de um caso clínico característico.

Orthodontic traction of impacted canines: Concepts and clinical application

ABSTRACT Orthodontic traction of impacted canines stands as a major challenge for Orthodontics. It is a relatively frequent clinical complaint which management, more often than not, requires a multidisciplinary approach. Surgical exposure of the impacted canine, and the complex orthodontic mechanics applied to align the tooth back into the arch, may frequently lead to complications involving supporting tissues, not to mention the long treatment time and high costs imposed to patients. In face of that, it is worth highlighting the relevance of early diagnosis as to intervene efficiently and as soon as possible. This paper presents a review of the main concepts involving prevalence, etiology and classification of impacted canines, and describes the different clinical management options that would help solve the problem. It illustrates the topic by presenting a treatment delivered to a 13 year 7 months old male patient, suffering from a Class II, division 2, left subdivision, malocclusion, associated to a deep bite and a prolonged retention of a primary upper canine caused by the impaction of the permanent tooth. Corrective orthodontic therapy was associated to a rapid maxillary expansion and to the use of a high pull headgear. Impacted canine was submitted to orthodontic traction and correctly positioned back into the arch. This approach proved to be efficient in meeting both functional and aesthetic goals.

RESUMO O tracionamento de caninos impactados representa um dos grandes desafios da Ortodontia. Trata-se de um problema clínico relativamente frequente, cujo tratamento muitas vezes requer uma abordagem multidisciplinar. A exposição cirúrgica do canino impactado e a complexa mecânica ortodôntica aplicada para alinhar o dente na respectiva arcada podem, com frequência, levar a complicações nos tecidos de suporte, sem mencionar o longo tempo de tratamento e os custos elevados para o paciente. Por isso, vale a pena ressaltar a importância dos diagnósticos precoces, para que a interceptação do problema seja feita o mais cedo possível e de maneira eficaz. O presente trabalho apresenta uma revisão dos principais conceitos envolvendo a prevalência, etiologia e classificação dos caninos impactados, e descreve os vários tipos de abordagem clínica para a resolução do problema. Ao final, ilustra o tema com a apresentação de um tratamento realizado em um paciente de 13 anos e 7 meses de idade, portador de má oclusão de Classe II, divisão 2, subdivisão esquerda, associado a mordida profunda, que apresentava retenção prolongada de um canino superior decíduo, devido à impacção de seu sucessor permanente. O tratamento ortodôntico corretivo foi associado à expansão rápida de maxila e ao uso de aparelho extrabucal de tração cervical. O canino impactado foi tracionado ortodonticamente e posicionado corretamente na arcada. Essa abordagem foi eficiente para atingir as metas funcionais e estéticas propostas.

"Maxillary lateral incisor partial anodontia sequence": a clinical entity with epigenetic origin

ABSTRACT The relationship between maxillary lateral incisor anodontia and the palatal displacement of unerupted maxillary canines cannot be considered as a multiple tooth abnormality with defined genetic etiology in order to be regarded as a "syndrome". Neither were the involved genes identified and located in the human genome, nor was it presumed on which chromosome the responsible gene would be located. The palatal maxillary canine displacement in cases of partial anodontia of the maxillary lateral incisor is potentially associated with environmental changes caused by its absence in its place of formation and eruption, which would characterize an epigenetic etiology. The lack of the maxillary lateral incisor in the canine region means removing one of the reference guides for the eruptive trajectory of the maxillary canine, which would therefore, not erupt and /or impact on the palate. Consequently, and in sequence, it would lead to malocclusion, maxillary atresia, transposition, prolonged retention of the deciduous canine and resorption in the neighboring teeth. Thus, we can say that we are dealing with a set of anomalies and multiple sequential changes known as sequential development anomalies or, simply, sequence. Once the epigenetics and sequential condition is accepted for this clinical picture, it could be called "Maxillary Lateral Incisor Partial Anodontia Sequence."

RESUMO A relação entre a anodontia parcial do incisivo lateral e o deslocamento palatino do canino superior não irrompido não pode ser considerada uma anomalia dentária múltipla com etiopatogenia genética definida, a ponto de ser considerada como uma "síndrome". Os genes envolvidos sequer foram identificados e localizados no genoma humano, e nem mesmo presumiu-se em qual cromossomo se localizaria o gene responsável. O deslocamento palatino do canino superior em casos de anodontia parcial do incisivo lateral superior está potencialmente associado às mudanças ambientais provocadas pela sua ausência no local de formação e erupção, o que caracterizaria uma etiologia epigenética para essa associação. A falta do incisivo lateral superior na região canina implica em tirar um dos guias referenciais da trajetória eruptiva do canino superior, que ficaria, assim, não irrompido e/ou impactado no palato. Como consequência, e em sequência, promove-se uma má oclusão, atresia maxilar, transposição, retenção prolongada do canino decíduo e reabsorções nos dentes vizinhos. Dessa forma, pode-se afirmar que estamos frente a um conjunto de anomalias e alterações múltiplas sequenciais conhecido como anomalias de desenvolvimento sequencial ou, simplesmente, sequência. Uma vez aceita a condição epigenética e sequencial para esse quadro clínico, ele poderia ser chamado de "Sequência da Anodontia Parcial do Incisivo Lateral Superior".

Causas locales de caninos permanentes retenidos en pacientes de la Clínica Estomatológica René Guzmán Pérez de Calixto García / Local Causes of Permanent Canines Retained in Patients of the René Guzmán Pérez Dental Clinic of Calixto García

Introducción: los dientes retenidos se consideran aquellos que llegada su edad cronológica de erupción no se encuentran en su lugar en la arcada dentaria. Objetivos: determinar las principales causas locales de caninos permanentes retenidos en pacientes ingresados en el Servicio de Ortodoncia de la Clínica Estomatológica René Guzmán Pérez del municipio de Calixto García. Métodos: se realizó un estudio observacional descriptivo transversal, desde enero de 2012 a enero de 2013. El universo investigativo estuvo representado por los pacientes ingresados en el Servicio de Ortodoncia. La muestra quedó conformada por 108 pacientes comprendidos entre los 10 y 19 años de edad, que acudieron a consulta, a los cuales se les realizó el diagnóstico de diente retenido. Resultados: el sexo femenino fue el más afectado con el 58,3%. En la posición subgingival, en el maxilar se observaron 61 pacientes (56,5%), 24 del sexo masculino (22,2%) y 37 del femenino (34,3%). La causa local mayoritaria fue la discrepancia hueso diente negativa observada en 45 pacientes (41,7%). Conclusiones: la retención canina predominó en el sexo femenino en proporción de 1,4/1, respecto al sexo masculino. La afección, fue observada mayoritariamente en la posición subgingival y particularmente en el maxilar superior. La discrepancia hueso diente negativa, el mantenimiento prolongado de los caninos temporarios y la pérdida prematura de dientes temporarios fueron las principales causas locales de la retención canina.

Introduction: impacted teeth are those that do not erupt in the right place of the dental arch at their chronological age. Objectives: to determine the main local causes of permanent impacted canines in admitted patients from the Orthodontic Service at René Guzman Pérez the Dental Clinic, in Calixto García municipality. Methods: an observational descriptive cross-sectional study was carried out from January 2012 to January 2013. Admitted patients from the Orthodontic Service with permanent impacted canines composed the investigation universe. The sample was composed by 108 patients between 10 and 19 years of age who presented to the clinic, to which a diagnose of retained teeth was made. Results: the female sex was the most affected one with 58.3%. In the subgingival position, in the maxillary arch, 61 patients were included (56.5%), 24 from male sex (22.2%) and 37 from females (34.3%). The major local cause was the tooth- bone negative disagreement observed in 45 patients (41.7%). Conclusions: the permanent impacted teeth was predominant in the female sex in proportion 1.4/1, in respect with male sex. The problem was mainly observed in subgingival position, particularly in the superior maxillary. The tooth- bone disagreement, the elongated maintenance of temporary canines and the premature loss of temporary teeth were the main local causes of canine retention.

The orthodontics treatment of severe skeletal class m malocclusion with bilateral maxillary impacted canines: A case report / 实用口腔医学杂志

An adolescent patient,in the peak of growth and development,with severe skeletal Class Ⅲ malocclusion and maxillary impacted canines was treated by removable and fixed appliances in the upper and lower dental arches.After treatment,the crossbite was relieved,the facial contour was improved,the integrity of the denture was kept and the Class Ⅰ molar relationship was achieved.

Maxillary Canine Impactions: Orthodontic and Surgical Management.

Canines are important teeth in terms of esthetic and function. The Maxillary Canines are also known as ‘Corner stone of smiles’ or ‘Eye teeth’. Impaction of canines is a common occurrence and clinicians must have a sound knowledge to manage such cases. Dachi and Howell reported that the incidence of maxillary canine impaction is 0.92%, and mandibular canine impaction is 0.35% among which 8% patients bilateral impactions. No prosthesis can match the originality of contour, shape and color of original canine. So every attempt should be made to retrieve the impacted canine. With early detection, timely interception and well managed surgical and orthodontic treatment; impacted canines can be erupted and guided to an appropriate location in the dental arch. This paper presents a literature review regarding etiology, clinical and radiographic diagnosis, as well as surgical and orthodontic management of impacted canine along with case presentations.

Crown-root morphology of adjacent lateral incisors in patients with palatally impacted maxillary canines:A cone-beam CT study / 医学研究生学报

Objective Maxillary canine palatal impaction is a common deformity in stomatology and its etiology remains dis-putable.The aim of this study is to investigate the crown-root morphology of the adjacent lateral incisors in patients with palatally impacted maxillary canines using cone-beam computed tomography ( CBCT) in order to explore its etiology. Methods Using CBCT scanning, we examined 94 maxillary canines in 84 patients, including 27 palatally impacted maxillary canines in 24 patients ( the experi- mental group) , 37 buccally impacted maxillary canines in 30 age-and sex-matched subjects ( control group A) , and 30 normal maxil-lary canines in 30 age-and sex-matched subjects ( control group B) .We selected some necessary reference planes, measured the ori-entation and position of the chosen canines, and studied the morphology of the adjacent lateral incisors by CS 3D imaging, followed by statistical analysis of 17 of the linear variables obtained. Results Compared with control group A, the experimental group showed significantly shorter tooth length ([22.930 ±1.849]mm vs [21.240 ±1.651]mm, P<0.05), crown length ([9.270 ±0.559]mm vs [8.150 ±0.889] mm, P<0.05), and mesiodistal width at 4 mm to the cementoenamel junction (CEJ) ([7.260 ±0.579]mm vs [5.900 ±0.581] mm, P<0.05) as well as shorter buccolingual width at the CEJ level, mesiodistal width at 4 mm to the CEJ, buc-colingual width at 4 mm apical to the CEJ, distance from the canine cusp to the coronal and occlusal planes, and coronal angulation of the canine (all P<0.05).There was a negative correlation between maxillary canine palatal impaction and age (P<0.05). Conclusion One of the main causes of maxillary canine palatal impaction is that the adjacent lateral incisor is too small to provide suf-ficient guidance to the canine.The severity of maxillary canine palatal impaction increases with the age of the patient.

Four impacted canines in an adult patient: A challenge in orthodontics.

This case report illustrates the management of four impacted canines in an adult patient associated with prolonged retention of the four deciduous teeth. The treatment plan was formulated to extract the lower deciduous teeth, application of the forced eruption with the permanent canines, and extract the upper permanent canines and maintenance of the maxillary deciduous canines. No reshaping of the maxillary deciduous teeth was performed because the patient was satisfied with the results.

A study of maxillary canine impaction and root resorption of adjacent incisor in three-dimensional space / 实用口腔医学杂志

Objective:To localize the impacted maxillary canine and to observe the root resorption of adjacent incisor in 3 dimen-sions using cone beam computed tomography(CBCT).Methods:92 impacted maxillary canines in 63 patients were scanned by CBCT.The three-dimensional images were obtained by multiplanar reconstructions(MPR).The cusp tip of each impacted canine was localized and set to the X,Y and Z planes after the observation of sagittal,coronal and axial views.The root resorption of adjacent in-cisors was observed.Results:In the X-axis,92% of impactions were mesial by 1 0.4 to 1 5.1 mm,8% distal by 2 to 5 mm;in the Z-axis,60% of impactions were palatal by 1 to 4 mm,40% buccal by 0 to 4 mm.41 .3% of the impacted canines were without root resorption of adjacent incisor,36.5% with slight,1 4.3% with moderate and 7.9% with severe root resorption of the adjacent inci-sor.Conclusion:The most frequent location of impacted maxillary canine is palatal and mesial with high incidence of root resorption of adjacent incisor.

Tracionamento ortodôntico-cirúrgico para caninos superiores impactados: revisão crítica e sugestão de protocolo / Surgical-orthodontic traction for impacted maxillary canines: a critical review and suggested protocolc

Maxillary canine impaction is a common occurrence, especially in the palate, despite sufficient space in the arch for tooth alignment. A proper approach requires knowledge of different specialties of dentistry, such as orthodontics, surgery, radiology, and periodontology, which are generally not centered on a single professional. The causes for canine impaction may be either generalized or localized, and the diagnosis should be made through specific clinical and radiographic examination. The prognosis of surgical–orthodontic treatment depends on the position of the canine in relation to the neighboring teeth and height of the alveolar process, in addition to careful surgical technique, considering that there are risks involved, such as ankylosis, loss of tooth vitality, root resorption of the involved tooth and adjacent teeth, and damage to supporting tissues. Given the important role played by impacted maxillary canines, their traction is the treatment of choice in orthodontically treated patients. The present study reviews the literature on important factors to be considered when approaching impacted canines, such as therapeutic possibilities, their advantages and disadvantages.

A impactação de caninos superiores é uma ocorrência freqüente, especialmente na região palatina, ainda que na presença de espaço suficiente para seu alinhamento na arcada. A abordagem exige conhecimentos de diferentes especialidades da odontologia, tais como a ortodontia, cirurgia, radiologia e periodontia e que, em geral, não se centram em um único profissional. Pode ser causada por fatores de ordem geral ou local, sendo que seu diagnóstico deve ser realizado por meio de exames clínico e radiográfico específicos. O prognóstico do tratamento ortodôntico–cirúrgico ira depender da posição do canino em relação aos dentes vizinhos e da sua altura no processo alveolar, além de técnica cirúrgica cuidadosa, haja vista que envolve riscos, como: anquilose, desvitalização, reabsorção radicular do dente envolvido e dos dentes adjacentes e dano aos tecidos de suporte. Em virtude das importantes funções desempenhadas pelos caninos inclusos superiores, o seu aproveitamento através do tracionamento é o tratamento de eleição nos pacientes assistidos ortodonticamente. O presente trabalho traz uma revisão bibliográfica acerca de importantes fatores a serem considerados na abordagem dos caninos impactados, tais como as possibilidades terapêuticas, suas vantagens e desvantagens.