Primary failure of eruption and tooth resorption / Défaut primaire d'éruption et résorption radiculaire externe

Introduction: The number of adult patients who seek an orthodontic treatment is increasing. These Primary failure of eruption (PFE) is defined as the partial or complete failure of eruption of at least one posterior tooth, without any mechanical obstacle. A better understanding of the biological mechanisms involved in PFE would enable to refine the diagnostic and prognostic criteria. This rare disease is currently related to PTHR1 gene variants. This gene codes for a transmembrane receptor involved in bone metabolism. However, there is few evidence associating PFE and bone remodeling abnormalities such as external root resorption. External root resorption is the loss of cementum and dentin tissues, resulting from the activation of clastic cells. Materials and Methods: Human teeth affected by PFE were extracted and histological sections were made after fixation of the tissues in 4% PFA. The observations were correlated with three-dimensional imaging by cone beam computed tomography (CBCT) carried out in the preoperative phase. Results: Histological and radiographic analysis confirm the presence of ankylosis area in patients with no history of orthodontic treatment. Large areas of resorption of external root replacement were detected. Discussion: The results call the causal link between the appearance of ankylosis areas and the establishment of orthodontic traction in patients with PFE into question. The installation of an orthodontic force in this context could be only an aggravating factor, accelerating the processes of ankylosis or triggering them more prematurely. Conclusion: With or without orthodontic treatment, teeth with PFE are likely to progress to ankylosis and resorption of replacement external root.

Introduction: Les défauts primaires d'éruption (DPE) se caractérisent par l'échec total ou partiel de l'éruption d'une ou plusieurs dents postérieures, sans obstacle mécanique. Une meilleure compréhension des mécanismes biologiques impliqués dans les DPE permettrait d'affiner les critères diagnostiques et pronostiques. Cette pathologie rare est actuellement imputée à des variants du gène PTHR1. Ce gène code pour un récepteur transmembranaire impliqué dans le métabolisme osseux. Cependant, on trouve peu de données associant DPE et anomalies du remodelage osseux de type résorption radiculaire externe. La résorption radiculaire externe correspond à la perte de tissus cémentaire et dentinaire résultant de l'activation de cellules clastiques. Matériels et méthodes: Des dents d'origine humaine atteintes de DPE ont été avulsées et des coupes histologiques réalisées après fixation des tissus. Les observations ont été corrélées avec l'imagerie tridimensionnelle par tomographie volumique à faisceau conique (TVFC ou encore CBCT). Résultats: Les analyses histologiques et radiographiques montrent la présence de plage d'ankylose chez des patients sans antécédent de prise en charge orthodontique. De larges zones de résorptions radiculaires externes de remplacement ont été détectées. Discussion: Les résultats remettent en cause le lien de causalité entre l'apparition d'ankylose et la mise en place de traction orthodontique chez les patients atteints de DPE. La mise en place d'une force orthodontique dans ce contexte pourrait n'être qu'un facteur aggravant, accélérant les processus d'ankylose ou les déclenchant plus prématurément. Conclusion: Avec ou sans traitement orthodontique, les dents atteintes de DPE sont susceptibles d'évoluer vers l'ankylose et la résorption radiculaire externe de remplacement.

The orthodontic-oral surgery interface. Part two: diagnosis and management of anomalies in eruption and transpositions.

The orthodontic-oral surgery interface is important for the multidisciplinary management of patients presenting with complex dental anomalies. This article provides an overview of anomalies of eruption and transpositions, their diagnosis, aetiology, presenting features and the different management options. It also highlights the role of the general dental practitioner (GDP) in identifying such anomalies and the importance of timely referral to specialist care.

[Diagnosis and management of ankylosed permanent maxillary incisors: proposal for a decision tree]. / Diagnostic et gestion des incisives maxillaires ankylosées : proposition d'un arbre décisionnel.

INTRODUCTION: Ankylosis of a maxillary incisor involves evolutive resorption for which clinical management is difficult for both general practitioners and orthodontists. This anomaly can give rise to potentially major aesthetic, functional and occlusal defects. The ankylosed tooth will be lost, in the short or long term, depending on the bone remodeling. MATERIALS AND METHODS: The aim of this review was to determine the different therapeutic options known to date and allow the construction of several clinical decision support systems (summary tables and decision tree). RESULTS: The different techniques were classified in three categories: abstention, conservative treatments and surgical treatments. The therapeutic objectives, indications and potential complications were listed for each technique. The possible persistence of an ankylotic zone or the ability to move the tooth after treatment was also recorded. DISCUSSION: The therapeutic solution is decided on after a precise diagnosis in order to evaluate the extent of the resorption and its localization. The chosen treatment will be more or less stable, conservative, aesthetic and expensive, and will have varying success rates. The time component must be taken into account and an individualised diagnosis and treatment plan are necessary to select the most appropriate therapeutic option for patients.

Ankylosis of Permanent First Molar: Diagnosis by Cone Beam Computed Tomography / Anquilosis del Primer Molar Permanente: Diagnóstico por Tomografía Computarizada con Haz Cónico

ABSTRACT: Ankylosis is an anomaly of tooth eruption characterized by the fusion of cementum and alveolar bone, and may affect from small regions to the entire root surface. Clinical assessment combined with imaging exams can aid diagnosis. Radiographic testing enables assessing only proximal regions of possibly affected roots. Whereas cone beam computed tomography (CBCT) allows a three-dimensional assessment of axial, coronal, and sagittal planes of all dental extension, eliminating thus overlapping images and helping to confirm the correct diagnosis. The present study contains a case report of a male patient with ankylosis in tooth 16 diagnosed by CBCT, aiming at providing information for dentists about this anomaly, its characteristics and situations in which CBCT should be indicated.

RESUMEN: La anquilosis es una anomalía de la erupción del diente caracterizada por la fusión de cemento y hueso alveolar, y puede afectar desde pequeñas regiones hasta toda la superficie de la raíz. La evaluación clínica combinada con los exámenes de imagen puede ayudar a diagnosticar esta anomalía. Las pruebas radiográficas permiten evaluar sólo las regiones proximales de las raíces posiblemente afectadas. La tomografía computarizada de haz de cono (CBCT) permite una evaluación tridimensional de los planos axial, coronal y sagital de toda la extensión dental, eliminando así las imágenes superpuestas y ayudando a confirmar el diagnóstico correcto. En el presente estudio se presenta un reporte de caso de un paciente con anquilosis en el diente 16 diagnosticado por CBCT, con el objetivo de proporcionar información para los dentistas sobre esta anomalía, sus características y situaciones en las que debe indicarse la CBCT.

Double Anterior Segmental Osteotomy Under Local Anesthesia for Correcting Adult Protrusion With Thin Alveolus and Ankylosed Tooth.

BACKGROUNDS: This paper describes an additional benefit in double anterior segmental osteotomy to correct severe anterior protrusion in adult patients with extremely thin mandibular alveolus and ankylosed tooth. For the optimal anterior segmental retraction, an ankylosed posterior tooth needed surgical inclination reposition. During anterior segmental osteotomy surgery under local anesthesia, additional single tooth osteotomy was performed without challenge. METHODS: For anterior segment retraction, osteotomy cuts were made by the surgeon to define a block of bone embedding 6 mandibular anterior teeth. First premolars were extracted during initial orthodontic treatment period. But the ankylosed lower left lateral incisor and lower right second premolar root which remains mesially with uprighted crown hindered further anterior segment retraction. The authors removed cortical bone around second premolar root and repositioned to be upright. Anterior segment was retracted to proper position utilizing the space gained. RESULT: Thin alveolar mandibular anterior segment retraction and the second premolar uprighting were managed effectively with additional single tooth segmental osteotomy during anterior segmental osteotomy. CONCLUSION: Double anterior segmental osteotomy can be an effective alternative to conventional orthognathic surgery in selected adult patients.

Timely relocation of subapically impacted maxillary canines and replacement of an ankylosed mandibular molar are the keys to eruption disturbances in a prepubertal patient.

Eruption disturbances such as impaction and ankylosis complicate orthodontic treatment because soft-tissue and hard-tissue considerations must be taken into account. Treatment is further complicated when such eruption disturbances occur in a growing patient. Extraction of impacted or ankylosed teeth can be an option that carries the weight of additional prostheses and bony defects, whereas exposure or luxation followed by orthodontic traction can preserve the patient's teeth and bony structure with improved esthetics. Therefore, an accurate diagnosis is needed in establishing an efficient and effective force system to achieve the desired tooth movements with few unwanted sequelae. This case report describes the process of differential diagnosis with the aid of 3-dimensional imaging in constructing a force-driven system, using the centers of resistance as reference points, to successfully bring a pair of impacted maxillary canines into alignment and protract a mandibular molar to achieve an acceptable occlusion in an adolescent girl.

Ankylosis of impacted canines: a retrospective post-surgical study.

Ankylosis is generally discovered following resistance to orthodontic displacement of an impacted canine. This retrospective study, drawing on direct perioperative observation of impacted teeth and of their sites, is intended, among other things, to analyze the causes of resistance to orthodontic movement and to report on the therapeutic interest of the surgical tooth displacement technique in this type of clinical situation. We demonstrate that primary coronal ankylosis can be detected by the orthodontic practitioner using radiographic records, that cervical ankylosis consequent to operative trauma during release is necessarily unpredictable and that it should be suspected when the tooth resists traction for more than 3 months in the absence of any other obvious cause of resistance. Hence, the risk of ankylosis linked to the level of surgical difficulty increases with the depth of coronal submergence within the bone. Moreover, the immediate placement of traction following release reduces the risk of ankylosis. In addition, temporarily suspending traction is a risk factor for secondary apical ankylosis. Finally, surgical positioning should be borne in mind as the final effective option when faced with any form of dental retention.

Establishing the diagnostic criteria for eruption disorders based on genetic and clinical data.

INTRODUCTION: Proper diagnosis and management of eruption disturbances remains challenging but is critical to a functional occlusion. The objective of this study was to establish definitive criteria to differentiate and diagnose eruption disorders, specifically primary failure of eruption (PFE) and ankylosis. METHODS: Sixty-four affected persons were placed into 3 cohorts: PFE diagnosed through confirmed PTH1R mutation (n = 11), PFE diagnosed based on clinical criteria (n = 47), and ankylosis diagnosed based on clinical criteria (n = 6). These groups were assessed to identify clinical features that differentiate PFE and ankylosis. RESULTS: Ninety-three percent of the subjects in the genetic and clinical PFE cohorts combined (n = 58) and 100% in the genetic PFE cohort had at least 1 infraoccluded first permanent molar. Additionally, a novel functional PTH1R mutation, 1092delG, was identified and linked to PFE in the deciduous dentition. CONCLUSIONS: An infraoccluded, supracrestal first molar is a hallmark of PFE, often involving both arches in the permanent or deciduous dentition, and with unilateral or bilateral affection, infraoccluded second premolar or second molar, and multiple affected adjacent teeth. Our results further suggest that PFE and ankylosis might be clinically indistinguishable without knowledge of prior trauma, treatment history, genetic information, or obliteration of the periodontal ligament space.

Tratamiento simultáneo de anquilosis temporomandibular unilateral congénita y del microlaterognatismo asociado / Simultaneously treament of congenital unilateral temporomandibular ankylosis and consecutive microlatherognathism

Este artículo tiene como objetivo reportar los resultados obtenidos a corto y largo plazo, del tratamiento con enfoque multidisciplinario de una anquilosis unilateral congénita de la articulación temporomandibular asociada a un síndrome de malformación embrionaria, en un niño de 12 años de edad, en el que se utilizó un distractor externo bidimensional con un doble propósito: como fijador para mantener el espacio logrado con la artroplastia y como distractor para elongar la rama mandibular hipotrófica, activado 5 días después de la osteotomía, con el objetivo de eliminar la anquilosis y el microlaterognatismo mandíbular consecutivo de ella, simultaneamente de manera funcional y dinámica(AU)

The paper reports the short- and long-term results obtained from the multidisciplinary treatment of a congenital unilateral ankylosis of the temporomandibular joint associated to an embryonic malformation in a 12-year-old boy, using an external bidimensional distraction device with a two-fold purpose: as fixator to maintain the space achieved by arthroplasty, and as distractor to elongate the hypotrophic mandibular branch, activated 5 days after osteotomy, with the purpose of eliminating ankylosis and consecutive mandibular microlaterognatism, both functionally and dynamically(AU)

Algorithm for the differential diagnosis of posterior open bites: two illustrative cases.

PURPOSE: Posterior open bites can result from several causes: trauma, degenerative changes, tongue thrust habits, single-tooth ankylosis, multiple-tooth ankylosis, and/or condylar hyperplasia. Occasionally, posterior open bites are secondary to a combination of condylar hyperplasia and dental ankylosis, which can be difficult to diagnose and treat because of the large array of causative problems. MATERIALS AND METHODS: This article presents 2 unusual cases of posterior open bite secondary to multiple etiologies in adolescent male patients. A useful method of algorithmic diagnosis, treatment, and protocol is presented that was used for these cases. RESULTS: The 2 cases were successfully diagnosed and treated using the formulated algorithm for posterior open bites. CONCLUSIONS: The algorithms presented facilitate the differential diagnosis of posterior open bites with ambiguous etiology.

Resonance frequency analysis: a new diagnostic tool for dental ankylosis.

Ankylosed teeth are considered in orthodontic treatment planning; however, diagnostic tools to quantify the rigidity of the tooth-to-bone connection are rare. Resonance frequency analysis (RFA) can quantify the rigidity of the dental implant-to-bone connection and thus may serve as a potential diagnostic tool to identify ankylosed teeth. To test this assumption, we examined 15 and 30 primary mandibular molars, with and without clinical signs of ankylosis, using the Osstell Mentor system. A cut-off implant stability quotient (ISQ) of 43 provided a specificity of 100% and a sensitivity of 53.3% when measured in the mesio-distal direction or a sensitivity of 20% when measured in the bucco-lingual direction. Based on a receiver-operating characteristic (ROC), the area under the curve (AUC) of 0.807 showed the mesio-distal direction of measurement to be a test of moderate discriminatory power. Given its non-invasiveness, RFA may serve as a quantitative diagnostic supplement to the clinical examination of potentially ankylosed primary molars.

Open bite: diagnosis, treatment and stability.

Open bite has fascinated Orthodontics due to the difficulties regarding its treatment and maintenance of results. This anomaly has distinct characteristics that, in addition to the complexity of multiple etiological factors, have aesthetic and functional consequences. Within this etiological context, several types of mechanics have been used in open bite treatment, such as palatal crib, orthopedic forces, occlusal adjustment, orthodontic camouflage with or without extraction, orthodontic intervention using mini-implants or mini-plates, and even orthognathic surgery. An accurate diagnosis and etiological determination are always the best guides to establish the objectives and the ideal treatment plan for such a malocclusion. This report describes two cases of open bite. At the end of the treatment, both patients had their canines and molars in Class I occlusion, normal overjet and overbite, and stability during the posttreatment period.

Open bite: diagnosis, treatment and stability

Open bite has fascinated Orthodontics due to the difficulties regarding its treatment and maintenance of results. This anomaly has distinct characteristics that, in addition to the complexity of multiple etiological factors, have aesthetic and functional consequences. Within this etiological context, several types of mechanics have been used in open bite treatment, such as palatal crib, orthopedic forces, occlusal adjustment, orthodontic camouflage with or without extraction, orthodontic intervention using mini-implants or mini-plates, and even orthognathic surgery. An accurate diagnosis and etiological determination are always the best guides to establish the objectives and the ideal treatment plan for such a malocclusion. This report describes two cases of open bite. At the end of the treatment, both patients had their canines and molars in Class I occlusion, normal overjet and overbite, and stability during the posttreatment period.

A mordida aberta tem fascinado enormemente a Ortodontia devido à dificuldade de tratamento e manutenção da estabilidade. É uma anomalia com características distintas que, além da complexidade dos múltiplos fatores etiológicos traz consequências estéticas e funcionais. De acordo com a etiologia, muitas mecânicas têm sido utilizadas no tratamento da mordida aberta, entre elas, grades palatinas, forças ortopédicas, ajuste oclusal, terapia de camuflagem com ou sem exodontias, intervenção ortodôntica com auxilio de mini-implantes ou mini-placas até a cirurgia ortognática. Considerando que um diagnóstico apropriado e a determinação da etiologia sempre serão os melhores guias para conduzir os objetivos e o plano de tratamento ideal desta maloclusão, dois casos de mordida aberta foram apresentados. Ao final do tratamento ambos os casos apresentaram oclusão de Classe I de caninos e molares, trespasse horizontal (overjet) e trespasse vertical (overbite) normais e na avaliação pós-contenção, mostraram estabilidade.

Anquilose dentária na dentição decídua e mista: revisão da literatura / Dental ankylosis in deciduous teeth: a literature review

O objetivo deste trabalho foi revisar a literatura sobre a o diagnóstico, conduta e seqüelas clínicas frente aos casos de pacientes que apresentam dentes anquilosados na dentição decídua e mista. A etiologia, tratamento e as consequências da presença dentes decíduos anquilosados ainda é escassa. Portanto, uma extensa busca na literatura sobre o assunto poderá colaborar para um melhor diagnóstico e conduta clínica pelo cirurgião dentista.

The objective of this study was to perform a literature review in the diagnosis, conduct and clinical sequels in patients with dental ankylosis in deciduous and mixed dentition. The etiology, treatment and consequences of the presence of dental ankylosis is still scarce. Therefore, a extensive search in the literature reports on the issue, could collaborate for a better diagnosis and clinical practice of the surgeon dentist.

Failure after closed traction of an unerupted maxillary permanent canine: Diagnosis and treatment planning.

This report describes the treatment of a 13-year-old girl with unerupted maxillary permanent canines. It illustrates how recognizing an unexpected problem influenced the decision-making process. Despite 6 months of closed-eruption traction, the left canine had not erupted. However, the neighboring teeth were intruded, suggesting a diagnosis of canine ankylosis. When the site was surgically reopened, the wire chain used for the orthodontic traction appeared to be osseointegrated. It was renewed, and traction was applied for another 16 months, and the tooth was successfully brought into the arch. Bone tissue passing through the chain might have prevented forced eruption. In young patients with unerupted maxillary permanent canines, failure of closed traction can be attributed to ankylosis, and this accounts for tooth extraction as the treatment of choice. However, this clinical report suggests that additional measures might be warranted before the definitive diagnosis of ankylosis can be made and the tooth extracted.

Tomografia computadorizada volumétrica de feixe cônico como método imaginológico auxiliar no diagnóstico de anquilose dentária: relato de caso clínico / Cone beam computed tomography as an imaging method to help at the diagnosis of dental ankylosis: a report of clinical case

O presente estudo apresenta um caso clínico de diagnóstico de anquilose alveolodentária com auxílio da tomografia computadorizada de feixe cônico.

Disruptions of the pulp-dentin complex in an investigated case of pink secondary retained molar.

A pink retained left mandibular first molar without carious lesions was diagnosed in a healthy 12-year-old girl presenting normal clinical tests. An orthopantomogram failed to detect other retained teeth. Both periapical radiography and computed tomography showed the absence of a periodontal ligament space in the bifurcation area and the presence of radiolucency or calcifications in the pulp cavity. The coronal part of the removed tooth was subjected to histological and immunohistochemical analysis using anti-PCNA (proliferation marker) and anti-p53 (apoptosis marker) antibodies. Root surfaces were observed by scanning electron microscopy. The pink color of the molar reflected the extension of resorptive tissue into the clinical crown and the underlining proliferation of pulp vessels. Ankylosis observed in the bifurcation area was also detected in the coronal part of the pulp. Whereas odontoblasts secreted tertiary dentin despite no evidence for a carious lesion, only osteocytes in the newly formed bone were apoptotic and the root surfaces were free of resorption lacunae. The etiopathology of the lesion in this case indicated a pulp origin, suggesting that new therapies targeting this tissue should be developed.