Incidence of Lower Anterior Third Molars on Dental Crowding. A New Approach / Incidencia de Terceros Molares Inferiores en el Apiñamiento Dental. Un Nuevo Enfoque

ABSTRACT: This paper main objective is to estimate the level of association between lower anterior crowding and the presence of lower third molars on study models and panoramic dental radiographs of patients treated by the Orthodontics Postgraduate Students at the Dentistry Faculty at the University of Cartagena (Cartagena de Indias, Colombia) and also other dental and radiographs care centers in Cartagena de Indias. It was made using a cross-sectional study at the Dentistry Faculty at the University of Cartagena and others dental care centers in the city. There were 366 study models and panoramic dental radiographs selected by strict inclusion/exclusion criteria for patients. An instrument that includes age, gender, presence or absence of third molars, position of third molars according to Winter's classification, stage of formation of the third molars according to Nolla's classification, and crowding magnitude according to Harfin's classification was used. Data were analyzed based on frequency distributions and proportions; inferential analysis was performed through proportional odds model using the software package IBM SPSS Statistics v23. It was found that the patients with Nolla 6 from the right side are more likely to have mild-moderate crowding magnitude than patients with Nolla 10 on that same side. In conclusion, this research provides as main result the implication of the eruption of the lower third molars and particularly those erupting in mesioangular and horizontal positions in the anterior crowding (AA).

RESUMEN: El objetivo de este trabajo fue estimar el nivel de asociación entre el apiñamiento dentario anteroinferior y la presencia de terceros molares inferiores en modelos de estudio y radiografías panorámicas de los pacientes atendidos por estudiantes del posgrado de ortodoncia de laFacultad de Odontología de Cartagena de Indias, Colombia y también otros centros dentales y de radiografías en Cartagena de Indias. Se realizó un estudio transversal en la Facultad de Odontología de la Universidad de Cartagena y otros centros de atención odontológica de la ciudad. Se utilizaron 366 modelos de estudio y radiografías dentales panorámicas seleccionadas por estrictos criterios de inclusión / exclusión para los pacientes. Se utilizó un instrumento que incluía edad, sexo, presencia o ausencia de terceros molares, posición de los terceros molares de acuerdo con la clasificación de Winter, etapa de formación de los terceros molares de acuerdo con la clasificación de Nolla y magnitud de apiñamiento según la clasificación de Harfin. Los datos se analizaron en base a las distribuciones y proporciones de frecuencia; el análisis inferencial se realizó a través del modelo de probabilidades proporcional utilizando el software IBM SPSS Statistics v23. Se encontró que los pacientes con Nolla 6 en el lado derecho son más propensos a tener una magnitud de apiñamiento de leve a moderada en comparación a los pacientes con Nolla 10 en ese mismo lado. En conclusión, esta investigación proporciona como resultado principal la implicación de la erupción de los terceros molares inferiores y particularmente aquellos que erupcionan en posiciones mesioangulares y horizontales en el apiñamiento dentario anterior (AA).

Premolar cystic ameloblastoma in a child

Mandibular swellings may occur as a result of many benign lesions of odontogenic or non-odontogenic origin. Ameloblastomas are benign tumours of odontogenic origin, whose importance lies in its potential to grow into enormous size with resulting bone deformity, it is a slow-growing, persistent, and locally aggressive neoplasm. The unicystic ameloblastoma [UA] represents an ameloblastoma variant, presenting as a cyst clinically and radiographically, but showing typical ameloblastomatous epithelium lining histologically. It commonly occurs in second and third decades of life and is rare in children under 12 years of age, and better response to conservative treatment. It shares many clinical and radiographic features with odontogenic cysts/tumours and/or periapical disease of endodontic origin. Reported here is an unusual case of unicystic ameloblastoma involving the crown of an unerupted mandibular first premolar in a 9-year boy in an uncommon location, which was misdiagnosed as periapical lesion of inflammatory origin clinically, and as a dentigerous cyst radiographically. This highlights the importance to routinely submit the removed surgical specimen for histopathological examination

Probabilidad de retención de segundos molares permanentes mandibulares (Estudio piloto) / Retention probability of permanent mandibular second molars (Pilot study)

Objetivos: Determinar la frecuencia del segundo molar mandibular permanente (MM2) con probabilidad de impactación, en un grupo de pacientes de Ortodoncia de Temuco, Chile. Método: Estudio de corte transversal, con muestra por conveniencia. Se revisaron 2095 fichas de individuos de ambos sexos, con ausencia de patología sindrómica. Los datos recolectados se obtuvieron de radiografías panorámicas. Se midió el ángulo del segundo molar con respecto al plano oclusal, la invasión distal del primer molar y la distancia entre distal del primer molar y el borde anterior de la rama mandibular. Resultados: El promedio de edad de los pacientes relevados fue de 10 años. Se observó un 1,43% de probabilidad de retención de MM2 (n=30); en promedio y el plano el ángulo MM2 resultó de 27° el izquierdo y 26° el derecho; la invasión de MM2 en distal del primer molar resultó de 1,5 mm; el ángulo entre MM2 y el planos oclusal es de 123°; la distancia entre la cara distal del primer molar y el borde anterior de la rama mandibular fue 13 mm. Conclusiones: Existe una baja prevalencia de segundos molares mandibulares permanentes con probabilidad de impactación. La invasión a la cara distal del primer molar fue mayor en pacientes con riesgo de impactación.

Objectives. To determine the frequency of risk of impaction of the permanent mandibular second molar (MM2) in a population of orthodontics patients in Temuco, Chile. Method. We conducted a cross-sectional study with a convenience sample. The records of 2095 individuals of both sexes with no syndromic pathology were analyzed. The data were obtained from panoramic radiographies. The following elements were measured: second molar angle in relation to the occlusal plane, distal invasion of the first molar and distance between the first molar and the front edge of the ramus. Results. The mean age of the individuals studied was 10. It was observed that 1.43 % presented MM2 retention probability (n=30) on average. The MM2 angle plane was 27° (left side) and 26° (right side). The invasion of MM2 in distal face of first molar was 1.5 mm on average. The angle between the occlusal plane and MM2 was 123°. The distance between the distal face of the first molar and the front edge of the ramus was 13 mm. Conclusions. The prevalence of MM2 risk of impaction is low. The invasion of the distal face of the first molar is more frequent in patients with risk of impaction.

Dentigerous cyst associated with dilacerated and inverted maxillary central incisor: an unusual case report / Cisto dentígero associado ao incisivo central superior invertido e dilacerado: relato de um caso incomum

One of the most common types of developmental odontogenic cyst is the dentigerous cyst. It encloses the crown of the tooth and is attached at the cementoenamel junction. Although its association with mandibular molars is common, it is rarely associated with the maxillary central incisors. Discussion: The present case report describes an unusual occurrence of dentigerous cyst associated with the impacted permanent maxillary central incisor in an inverted position and showing dilaceration of the root. The cyst was enucleated along with the extraction of the impacted tooth. We have discussed clinical presentation, radiographic features and treatment modalities of this uncommon and rare presentation of this lesion. Conclusion: Trauma to the deciduous teeth should not be overlooked, since it can result in the development of a pathology which could indirectly affect the permanent successors...

Um dos tipos mais comuns de cisto odontogênico de desenvolvimento é o cisto dentígero. Ele inclui a coroa do dente e está conectado à junção cemento-esmalte. Apesar de sua associação com molares inferiores ser comum, ele raramente está associado com incisivos centrais superiores. Discussão: O presente relato descreve um caso raro de cisto dentígero associado ao incisivo central superior permanente impactado em uma posição invertida, apresentando dilaceração da raiz. O cisto foi enucleado durante a extração do dente afetado. Foram discutidas a apresentação clínica, as características radiográficas e as modalidades de tratamento desta apresentação incomum e rara de lesão. Conclusão: O trauma em dentes decíduos não deve ser negligenciado,pois pode resultar no desenvolvimento de uma patologia que pode afetar indiretamente os sucessores permanentes...

The histopathological examination of the dental follicleof asymptomatic impacted tooth: is it necessary? / Exame histopatológico do folículo dental de denteimpactado assintomático: é necessário?

Introduction: During the development of a tooth, the pericoronal tissue may develop pathological changes.The clinical dilemma occurs in the early diagnostic of the tissue around the crown of an uneruptedtooth. Objective: The purpose of this paper is to present a clinical case with different diagnoses of a smallradiolucency area around the crown of impacted teeth on the same patient. The histological diagnosis ofthe follicle related to tooth 48 was of dentigerous cyst and the histological finding of follicular tissue associatedto tooth 38 showed some features of unicystic ameloblastoma. The follicles of teeth 18 and 28 didnot present histopathological changes. Conclusion: The radiographic appearance may not be a reliableindicator of the absence of disease in pericoronal tissues. We recommend histopathological analysis onall surgically extracted follicle tissue, even when radiographic and clinical findings are not indicative ofpathological alterations.

Introdução: Durante o desenvolvimento dental, o tecido pericoronário pode sofrer alterações patológicas.O dilema clínico está no diagnóstico precoce dos tecidos em torno da coroa de um dente retido. Objetivo: O objetivodeste trabalho é apresentar um caso clínico em que houve diferentes diagnósticos histológicos relacionadosaos tecidos pericoronários em um mesmo paciente sem a presença de alteração radiográfica característica.Os diagnósticos histológicos dos folículos dos terceiros molares sugeriram cisto dentígero relacionado ao dente48, características de ameloblastoma unicístico ao dente 38, e os tecidos dos dentes 18 e 28 não apresentaramalterações histopatológicas. Conclusão: O aspecto radiográfico neste caso não foi um indicador confiável daausência de doença em tecidos pericoronários. Logo, recomendamos que todos os tecidos pericoronários sejamencaminhados para o exame histopatológico mesmo que os achados radiológicos e clínicos não mostrem alteraçõespatológicas.

Erupted compound odontome associated with impactedmaxillary second premolar: a case report / Odontoma composto erupcionado associado a segundopré-molar superior impactado: um relato de caso

Introduction: Odontomas are the most common odontogenic tumour. They are considered to be hamartomasrather than neoplasms. They are generally asymptomatic and are discovered on routine radiographicexamination. Odontomas might be associated with disturbance in tooth eruption. Other symptoms includeretention of deciduous teeth, pain, swelling, expansion of cortical bone, tooth displacement. Eruption ofodontoma in the oral cavity is rare with only 11 cases being reported about erupted compound odontomas.Case report: An unusual case of erupted compound odontome associated with pain and impacted maxillaryleft second premolar is reported. We have also discussed the clinical, radiographic and histopathologicfeatures of this rare condition.

Introdução: Odontomas são os mais comuns entre os tumores odontogênicos. Eles são considerados hamartomas,ao invés de neoplasias. Eles geralmente são assintomáticos e descobertos em exames radiográficos derotina. Odontomas podem estar associados com distúrbio na erupção dentária. Outros sintomas incluem retençãode dentes decíduos, dor, inchaço, expansão do osso cortical e deslocamento do dente. A erupção de um odontoma na cavidade oral é rara, com apenas 11 casos relatados de odontomas compostos erupcionados.Relato de caso: Um caso incomum de odontoma composto associado à dor e segundo pré-molar superior esquerdoimpactado é relatado neste artigo. Os aspectos clínicos, radiográficos e histopatológicos dessa doençarara também são discutidos.

Influence of dental exposure to oral environment on smear layer removal and collagen exhibition after using different conditioning agents

Although in vitro studies have shown encouraging results for root surface conditioning with demineralizing agents, in vivo studies have failed to show its benefits in periodontal healing. This can be attributed to several factors, among which, the hypermineralization of dental surface. Therefore, this in vitro study compared, using scanning electron microscopy (SEM), the effect of root surface conditioning with different conditioners (1% and 25% citric acid, 24% EDTA and 50 mg/mL tetracycline hydrochloride) in impacted teeth and in teeth that had their roots exposed to the oral environment. One trained examiner assessed the SEM micrographs using a root surface modification index. There was a tendency of more root surface modification in the group of impacted teeth, suggesting that the degree of root mineralization influences its chemical demineralization.

Apesar de estudos in vitro terem demonstrado resultados favoráveis ao condicionamento da superfície radicular com agentes desmineralizantes, estudos in vivo não mostraram seus benefícios na cicatrização periodontal. Isto pode ser atribuído a vários fatores, entre os quais, a hipermineralização da superfície dental. Portanto, este estudo in vitro comparou, usando microscopia eletrônica de varredura, o efeito do condicionamento da superfície radicular com diferentes condicionadores (1% e 25% de ácido cítrico, EDTA 24% e 50 mg/mL de cloridrato de tetraciclina) em dentes impactados e dentes que tinham suas raízes expostas ao meio bucal. Um examinador treinado avaliou as microscopias eletrônicas de varredura utilizando um índice de modificação da superfície radicular. Houve uma tendência de maior modificação da superfície radicular no grupo de dentes impactados, sugerindo que o grau de mineralização da raiz influencia a sua desmineralização química.

Bilateral lower second molar impaction in teenagers: An emergent problem.

The frequency of simultaneously impacted second and third molars in teenagers is increasing and becoming a common occurrence in adolescent oral surgery practice. The traditional treatment is the removal of the third molar by conventional access but repositioning of the surgical flap to the distal face of the first molar can predispose to complications such as pericoronitis and delayed healing of the attached gingiva. We present a case in which we use the germectomy approach to remove the impacted third molar for the eruption of the second molar through a vestibular incision. This incision offers excellent bone exposure and exit route for the third molar without disturbing the gingiva attached architecture on the distal face of the first molar providing good healing environment.

Pathosis associated with radiographically normal follicular tissues in third molar impactions: a clinicopathological study.

BACKGROUND: The follicular tissue around impacted third molars has a potential to develop pathosis. However, it is generally assumed that the absence of abnormal radiolucency indicates the presence of a normal follicle. AIMS: The aim of this study was to investigate abnormalities associated with radiographically normal follicular tissue of third molar impactions. MATERIALS AND METHODS: One hundred eighty-five impacted third molars from 170 patients with no signs of abnormal radiolucency (follicular space < 3 mm) were used for this study. Follicular tissues of the relevant teeth were collected. Specimens were fixed in 10% formalin and stained routinely with hematoxilin and eosin to be independently examined by two pathologists. A diagnosis was registered only when the results from both pathologists were in concordance. Clinical details for each patient were registered in WHO standard forms to undergo chi-square statistical analysis. RESULTS: Fifty-three per cent of the specimens had developed pathosis. The incidence of pathosis was higher in the age group of 20-30 years, in men compared to women and in the mandible compared to the maxilla. CONCLUSION: The findings of this study suggest that radiographic appearance may not be reliable in the diagnosis of pathosis in follicular tissue as a surprisingly high rate of pathosis was found in the absence of any radiographically detectable sign.

[Evaluation of histopathologic changes in impacted third molar follicles in Mashhad dental school in 2005]

Since remaining impacted teeth may result in pathologic lesions, prophylactic extraction of third molar-which is the most frequent impaction-is among the most common surgical procedures. Our study was performed to evaluate the histopathoiogical changes of impacted molar teeth follicles. In this descriptive study, 54 impacted molar teeth follicles of 50 patients with age range of 15-38, and examined in the surgery ward of Mashhad dental school from June to November 2005, were extracted by a surgeon and pathologic evaluation were performed. In this study, the most commonly extracted teeth were mandibular molars [79%] and 74% of patients were under 25. The most frequent location of the extracted teeth was mesioangular [46%]. In microscopic evaluation of specimens, 61% were unchanged dental follicles, 12.9% were odontogenic cysts and 24% had inflammation. Considering the low incidence of pathologic changes in impacted third molar follicles, it is better not to extract them except in a clear indication. These teeth are better to be monitored by imaging with the 6-12 month intervals

Comparative Ki-67 Expression and Apoptosis in the Odontogenic Keratocyst Associated with or without an Impacted Tooth in Addition to Unilocular and Multilocular Varieties

It is not known whether the presence of an impacted tooth or the radiographic types in an odontogenic keratocyst (OKC) change the clinical biologic behavior and therapeutic approaches. This study evaluated the comparative proliferative activity and apoptosis in OKC associated with or without an impacted tooth, as well as between the unilocular and multilocular OKC varieties. Immunohistochemical expression of Ki-67 as a proliferation marker and the apoptotic reactions were assessed by the TUNEL method for 32 cases of OKC (OKC with impacted tooth, n=16; OKC without impacted tooth, n=16) and 10 cases of dentigerous cyst (DC). OKC showed a greater proliferative potential and more apoptotic reactions than DC. In particular, OKC contained proliferating and apoptotic cells situated predominantly in the suprabasal and superficial layers, respectively. However, no significant difference was found between OKC associated with or without impacted tooth, or between the unilocular and multilocular OKC varieties, in terms of proliferative activity or apoptosis. In conclusion, OKC is characterized by an increase in both cell proliferation and apoptosis, suggesting a unique proliferative and differentiation process. It is believed that incomplete removal or other contributing factors, rather than intrinsic growth or apoptosis, may be the main reasons for the aggressive biologic behavior or recurrence in multilocular OKC.

Os caninos e os seus envolvimentos no equilíbrio estético, tracionamento de caninos näo irrompidos: uma controvérsia / Envolvment of canines in esthetical equilibrium, traction of impaired canines: a controversy

Os autores demonstram a importância deste controvertido assunto ser revisado, visando näo preconizar um tratamento mas, sim, discutir os trabalhos e as experiências de vários pesquisadores para que cada profissional possa estabelecer o seu modo de atuaçäo