O ameloblastoma é uma das neoplasias odontogênicas mais freqüentes universalmente. Seu estudo se reveste de grande importância porque, não obstante benigna, é localmente agressiva, com alto índice de recorrências, sendo o tratamento cirúrgico radical, com margem de segurança, freqüentemente preconizado, e tido, por boa parcela de especialistas, como única alternativa efetiva para seu tratamento. Em decorrência, observam-se, muitas vezes, seqüelas importantes, do ponto de vista funcional e estético, para os pacientes acometidos por essa neoplasia. O objetivo do presente trabalho foi revisar a literatura, traçando um perfil comparativo, por continente, da biodemografia do ameloblastoma, com ênfase na discussão de suas possíveis diferenças e similitudes regionais. As informações coletadas na literatura disponível para consulta indicaram ter sido a segunda neoplasia de origem odontogênica mais prevalente universalmente, ressalvada a consideração sobre os odontomas serem ou não, classificados como neoplasias. Foi mais freqüente no gênero masculino. A localização mais comum do ameloblastoma foi no segmento posterior da mandíbula, sendo essa, uma unanimidade nos trabalhos consultados. Houve diferenças regionais quando se comparou aspecto relativo aos itens estudados (freqüência do ameloblastoma em relação às neoplasias odontogênicas; incidência do ameloblastoma em relação ao gênero). Foi encontrada, na revisão de literatura pesquisada, uma freqüência significativa de informações incompletas com relação aos itens estudados, sendo exceções, os trabalhos referentes aos continentes, europeu e africano / Ameloblastoma is one of the universally most prevalent odontogenic neoplasias. Its correct knowledge has great importance in view of its local aggressiveness potential, although being a benign neoplasia, with a high number of recurrences. The elective treatment for ameloblastoma is the surgical radical resection with safety margins, being in the opinion of many specialists, the only correct method for its management. Notwithstanding of this fact, functional and aesthetical damage has been frequently observed after treatment, among the patients suffering from this neoplasia. The purpose of the present study was to perform a literature review, building a comparative continental profile of ameloblastoma biodemographics, emphasizing the discussion of its possible regional differences and similarities. The information collected from the literature indicated ameloblastoma as the second most frequent odontogenic neoplasia, despite of the consideration on the odontoma classification as a true neoplasia or not. Ameloblastoma was more frequent among male gender and the most common location was in the posterior segment of the jaw, being this data unanimous among the literature. There were regional differences regarding some of the studied variables (freqüency of ameloblastoma related to odontogenic neoplasias and related to gender). Incomplete data was an important occurrence during the literature reviewing, with exception of the papers from European and African continents.

Orientador: Fábio Ramôa Pires / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-19T10:43:01Z (GMT). No. of bitstreams: 1 Romanach_MarioJose_D.pdf: 5231704 bytes, checksum: 202539e51f52c9c5972d8aedecc9f4c9 (MD5) Previous issue date: 2011 / Resumo: Cistos gengival do adulto (CGA), periodontal lateral (CPL) e odontogênico glandular (COG) são cistos odontogênicos raros que apresentam características microscópicas similares e comportamento clínico distinto. O objetivo deste trabalho foi comparar o perfil clínico-patológico e imunoistoquímico de 45 casos destes três tipos de cistos odontogênicos (CGA = 14, CPL = 15, COG = 16) oriundos de 4 diferentes laboratórios de Patologia Oral. Os CGAs acometeram principalmente na gengiva da região de pré-molares inferiores de mulheres com média de idade de 56 anos. Os CPLs acometeram principalmente as regiões anterior e de pré-molares da mandíbula de mulheres com média de idade de 54 anos. Os COGs acometeram principalmente a região de molares mandibulares de mulheres com média de idade de 50 anos. Microscopicamente, epitélio com espessura maior que 5 camadas contendo estruturas intra-epiteliais pseudo-ductais, células colunares e mucosas foram observadas predominantemente nos COGs quando comparados aos CGAs e CPLs. A positividade para CK 5 e CD138 foi encontrada principalmente nas camadas basal e intermediária enquanto que CKs 8 e 19 marcaram as camadas intermediária e superficial dos três tipos de cistos. COGs apresentaram índice de positividade para p63 aumentado (59%) em relação aos encontrados em CGAs (26%) e CPLs (48%). A cápsula de COGs mostrou maior positividade para actina de músculo liso-alfa e CD138 quando comparada aos CPLs e CGAs. Concluimos que CGA, CPL e COG possuem características histopatológicas e imunoistoquímicas similares que podem justificar uma provável origem comum / Abstract: Gingival cyst of adult (GCA), lateral periodontal cyst (LPC) and glandular odontogenic cyst (GOC) are rare odontogenic cysts that present similar microscopic features and distinct clinical behavior. The aim of the present study was to compare the clinicopathological and immunohistochemical profile of 45 cases of these 3 types of odontogenic cysts (GCA = 14, LPC = 15, GOC = 16) from 4 different Oral Pathology laboratories. GCA mainly affected the gingiva of the lower pre-molars region of women with median age of 56 years-old. LPC mainly affected the anterior and pre-molars regions of the mandible of women with median age of 54 years-old. GOC mainly affected the mandibular molars region of women with median age of 50 years-old. Microscopically, epithelium with more than 5 layers containing duct-like intraepithelial structures and colunar and mucous cells were predominantly observed in GOC when compared to GCA and LPC. The positivity for CK 5 and CD138 was mainly observed in the basal and intermediate layers while CK 8 and CK 19 staining was seen in the intermediate and superficial layers of the cystic epithelium in all cysts. GOC presented higher p63 positivity index (59%) comparing with those found in GCA (26%) and LPC (48%). The connective tissue capsule of GOC exhibited higher positivity for smooth muscle actin and CD138 when comparing with GCA and LPC. We conclude the GCA, LPC and GOC share similar microscopic and immunohistochemical features that could justify a likely common origin / Doutorado / Patologia / Doutor em Estomatopatologia

Orientador: Oslei Paes de Almeida / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-26T10:32:36Z (GMT). No. of bitstreams: 1 Martinez_MarisolMartinez_D.pdf: 11593706 bytes, checksum: 9204e3ab03e2563ba5f0fa74b21ca2e2 (MD5) Previous issue date: 2014 / Resumo: Os tumores odontogênicos (TO) são um grupo heterogêneo de lesões derivadas de tecidos dentários, que ocorrem nos ossos gnáticos e tecidos adjacentes. Os TO são raros, na grande maioria benignos, representando menos de 4% de todos os espécimes recebidos em laboratórios de patologia bucal. Os TO malignos frequentemente apresentam dificuldades para diagnóstico e correta classificação, com vários pontos ainda não bem esclarecidos. O objetivo desse trabalho foi comparar as características clínicas, histológicas e imunohistoquímicas do carcinoma ameloblástico (CA) e fibrosarcoma ameloblástico (FSA) e dos seus respectivos correspondentes benignos ou seja ameloblastoma (AM) e fibroma ameloblástico (FA). O carcinoma escamocelular intra-ósseo primário (CEIP) também foi comparado com carcinoma escamocelular de mucosa bucal (CEMB). Foi avaliada a expressão imunohistoquímica de citoqueratinas 5, 7, 8, 14, 19, marcadores de proliferação celular Ki-67, p53, p63 e moléculas de adesão celular CD138 (Syndecan), E-cadherin e ?-catenin. Os resultados mostraram que o CA expressaram mais altos níveis Ki-67, p53 e p63 do que AM por tanto, poderiam ser usados como marcadores para diferenciar essas duas lesões. A expressão de CKs 5 e 19 foram alteradas com relação ao padrão observado em AM, pelo que alterações genéticas de essas proteínas poderiam estar presentes nas células malignas. CK19 pode ser um bom marcador para tumores odontogênicos benignos como AM mas não em malignos pois a expressão nestes é variável. Nas moléculas de adesão celular particularmente CD138 não foi observada diminuição da expressão em AC comparada com AM. As características histológicas assim como o perfil imunohistoquímico do CEMB e CEIP foram similares, por tanto, sugere-se que as características clínicas e radiográficas sejam os principais parâmetros para ser considerados no diagnóstico. Nos casos de fibroma ameloblástico (FA) e fibrosarcoma ameloblástico (AFS) a expressão de CKs foi similar em intensidade e localização e Ki-67 em FSA foi mais alto comparado com FA enquanto que p53 foi negative e ambas lesões. A expressão das moléculas de adesão foi similar em ambas lesões sendo mais intensa com CD138. Finalmente, foram ilustradas as características clínicas e histopatológicas de um caso de fibroodontoma ameloblástico pigmentado e um caso de CEIP originado a partir da transformação maligna de um queratocisto / Abstract: Odontogenic tumors correspond to a heterogenous group of lesions derived from dental tissues, involving the jaws and adjacent tissues. OT are rare, the majority benign, representing less than 4% of all specimens of an oral pathology laboratory. OTs frequently present difficulties for the correct diagnosis and classification, with various points yet to be clarified. The objective of this study was to analyze the clinical, histological and the expression of immunohistochemical markers in malignant odontogenic tumors and the benign counterparts. We assessed CK5, 7, 8, 14, 19, Ki-67, p53, p63, CD138 (Syndecan), E-cadherin and ?-catenin expression by immunohistochemistry in 15 and 9 cases of ameloblastoma (AM) and ameloblastic carcinoma (AC) respectively. Dez cases of primary intraosseous squamous cell carcinoma (PIOSCC), 9 cases of squamous cell carcinoma of mouth (OSCC), 8 cases of ameloblastic fibroma and ameloblastic fibrosarcoma (AFS). Also, these were compared expression patterns between these groups. In summary, Ki-67, p53 and p63 expression were higher in AC than in AM and could be used as markers of malignant transformation of AM. CKs 5 and 19 expression in AC are altered in relation to the pattern found in AM, also CK19 is a good marker for benign odontogenic tumors as AM. Our results do not permit to confirm that expression of CD138, is decreased in AC in relation to AM. The histological features as well as the immunohistochemical profile of OSCC and PIOSCC were similar, therefore, suggests that the clinical and radiographic features are the main parameters to be considered for diagnosis. In both AF and AFS the CKs expression in odontogenic islands was similar in intensity and localization, except CK7 that in most cases of AF was focally positive, while in AFS most cases were negative. Ki-67 proliferative index was higher in AFS that in AF, and p53 was negativo in both lesions. Expression of adhesion molecules was similar in AF and AFS, being most intense for CD138 / Doutorado / Patologia / Doutora em Estomatopatologia

No description available.

ABSTRACT Objectives: Cone beam computerized tomography use is becoming more common in preparation for surgical planning and treatment diagnosis by clinicians. The scanning result gives clinicians a more accurate understanding of each patients’ anatomy, which aids in designing better treatment plan, avoidance of vital anatomy, etc. Modern treatments involving extraction of teeth has become more sophisticated due to advent of dental implant treatment. Along with the procedure, more sophisticated treatment techniques involving manipulation of sinus has flourished. Traditional periapical and panoramic radiograph are not as adapt at identifying sinus pathologies. As patients age, proximity of sinus floor and apex of teeth may become closely related where possibility of one affecting another is observed. This study aims to study the prevalence of odontogenic related pathologies in relation to maxillary sinus in the population who had CBCT images taken at Temple University Kornberg School of Dentistry. The study also looks in detail the relationship of such pathology in relation to teeth status, age, gender, and ethnicity. Methods: 821 CBCT scans completed at Temple University Kornberg School of Dentistry Department of Oral Maxillofacial Radiology from January 1st, 2009 to July 31, 2013 were evaluated with iCAT computer imaging software. Patients under 18, no posterior dentition, or complete edentulous were excluded from the study. A total of four hundred fourty four (444) CBCT scans were included in the study. Patients with odontogenic related maxillary sinus pathology were selected and teeth status, age, gender and ethnicity recorded. Individual scans had sinus pathology identified and examined for proximity and relationship to respective tooth/teeth. Each individual tooth’s status were also recorded. Chi-square test was conducted to verify validity Results: After reviewing 680 scans, only 444 were included in the study due to exclusions. Scans were subdivided by age (18-35: 77, 36-53: 113, 54-71: 188, 72> : 46), gender (280 male and 164 female), ethnicity (African American 86, Asian 45, Caucasian 291, Hispanic 22), tooth status (caries, 26, crown 87, healthy 31, impacted 11, root canal 88, restoration 58), tooth position ( 3rd molar 9, 2nd molar 86, 1st molar 138, 2nd premolar 20, 1st premolar 6, canine 3). Overall 63.06% of scans were classified as healthy, and 36.04% were classified as presenting odontogenic related maxillary sinus pathology. None of the parameters showed significant predilection to odontogenic related pathology, however, 1st molar has the highest risk of exhibiting pathology in the maxillary sinus with 2nd molar second. The pathology incidence rates are slightly higher in male patients 41% vs 34%. Age is not a significant factor as all age groups demonstrates similar incidence rate except 72> group. Dentition status showed root canal and crown being the most commonly associated with pathology at 29% each. In Caucasian population, crown and root canal was most commonly related. African American was restoration and healthy teeth. Asian population had the most link with large restorations. Conclusions: Maxillary 1st molar is the most commonly involved tooth with maxillary sinus pathologies with 2nd molar as second most common. Caucasian individuals had the most odontogenic related pathologies. In general, crown and root canal are associated with a significant number of pathologies found in the sinus and should be evaluated prior to any surgical evaluation prior to any sinus manipulative surgery or odontogenic treatment. / Oral Biology

O tumor odontogênico queratocístico (TOQ) é uma neoplasia cística benigna originada de remanescentes epiteliais da odontogênese, que se destaca pela alta recorrência e eventual associação com a síndrome do carcinoma nevóide de células basais (SCNCB). O presente estudo buscou responder questionamentos relacionados à sua terapêutica cirúrgica e suprir a carência de pesquisas atuais sobre as lesões associadas à SCNCB, que são ainda mais recorrentes, analisando uma amostra formada por 40 TOQs primários. As variáveis de interesse determinaram grupos amostrais, que receberam análise dos tempos livres de recorrência por função Kaplan-Meier, comparação desses tempos pelo teste log-rank com nível de significância de 5% (p < 0,05) e determinação do risco acumulado para o evento nos primeiros cinco anos. Vinte e sete lesões foram tratadas por exérese (GE) e 13 receberam terapêutica descompressiva (GD). Tratamentos complementares ocorreram em 38 (95%) lesões, sendo ostectomia periférica isolada em 10 (GO) e combinada à solução de Carnoy em 28 (GC). Treze eram associadas à SCNCB (GS) e as demais (n = 27) representaram lesões não sindrômicas (GnS). No período de acompanhamento médio de 43,5 meses (12 102 meses), seis (15%) recorrências foram diagnosticadas. Não houve diferença significativa entre os tempos livres de recorrência nos grupos comparados (p > 0,05), nem expressividade do risco acumulado para o evento na terapêutica descompressiva (15,4%) e na associação com a SCNCB (12,5%). A aplicação da solução de Carnoy não aumentou a efetividade da ostectomia periférica, mas se relacionou com risco acumulado de recorrência de 0% ao final do quinto ano de acompanhamento pós-exérese nas lesões sindrômicas. Portanto: 1) a terapêutica descompressiva não aumentou o risco para recorrências; 2) a ostectomia periférica mostrou efetividade similar quando combinada à solução de Carnoy, pelo menos nas lesões não associadas à SCNCB; 3) o risco de recorrência das lesões associadas à SCNCB também foi controlado por tratamentos complementares. / The keratocystic odontogenic tumor (KOT) is a benign cystic neoplasm originating from odontogenic epithelial remnants which is highlighted by its high recurrence rate and occasional association with the nevoid basal cell carcinoma syndrome (NBCCS). The present study aimed to answer questions related to its surgical therapy and to fulfill the lack of recent researches over the lesions associated to the NBCCS, which are even more recurrent, analyzing a sample ok 40 primary KOTs. Variables of interest determined sample groups that underwent recurrence-free period analyses by Kaplan-Meier function, comparing these results by log-rank test with a significance level of 5% (p < 0.05) and determination of cumulative risk for the recurrence event within the first five years. Twenty seven lesions were treated by exeresis (GE) and 13 underwent decompressive therapeutic (GD). Complementary treatment occurred in 38 (95%) lesions being as isolated peripheral ostectomy in 10 (GO) and combined with Carnoys solution in 28 (GC). Thirteen were associated to NBCCS (GS) and the others (n = 27) represented non syndromic lesions (GnS). For the mean follow-up period of 43.5 months (12 102 months), six (15%) recurrences were diagnosed. There was no significant difference among recurrence-free periods for the compared groups (p > 0.05) or cumulative risk expression for the decompressive therapeutic (15.4%) or for the association with NBCCS (12.5%). Carnoys solution application did not increase the efficacy of the peripheral ostectomy but was related to the cumulative recurrence risk of 0% at the end of the fifth year of post-exeresis follow-up for syndromic lesions. Therefore: 1) the decompressive therapeutic did not increase the recurrence risk; 2) peripheral oostectomy demonstrated similar efficacy when combined to Carnoys solution, at least for lesions not associated to NBCCS; 3) the recurrence risk of lesions associated to NBCCS was also controlled by complementary treatments.

Made available in DSpace on 2015-05-14T12:55:59Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2259419 bytes, checksum: 7fa6d27f4906e00633cba96e2058ad2a (MD5) Previous issue date: 2011-12-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Metaplastic and degenerative changes are usually observed in the epithelial lining of odontogenic cysts. These processes in odontogenic tumors are considered rare. This study aimed to conduct a study to assess the presence and biological significance of clear cells in the epithelial lining of a series of odontogenic cystic lesions. A total of 48 histological slides of these lesions were examined by two calibrated examiners. The paraffin blocks corresponding to the lesions that were observed in clear cell were re-processed and 22 slides were stained by the periodic acid Schiff (PAS) after diastase digestion, and evaluated for the presence of mucous cells. It was performed a descriptive statistical analysis of data and these were represented as graphs and tables. Mucous cells were found in 41,66% cases of radicular cysts, 50% of keratocystic odontogenic tumors, 100% of dentigerous cysts and 100% of unicystic ameloblastomas. The results of this research may suggest that degenerative and metaplastic phenomena usually occur in the epithelium of odontogenic cysts and odontogenic cystic tumors, which may represent a phenomenon associated with the chronic inflammatory process that is usually observed in these lesions, or be indicative of the multipotentiality odontogenic epithelium. / Alterações degenerativas e metaplásicas são usualmente observadas no revestimento epitelial dos cistos odontogênicos. Nos tumores odontogênicos estes processos são considerados mais raros. Esta pesquisa objetivou realizar um estudo para avaliar a presença e o significado biológico das células claras no revestimento epitelial de uma série de lesões odontogênicas císticas. Um total de 48 lâminas histológicas das referidas lesões foram examinadas por dois avaliadores previamente calibrados. Os blocos parafinados correspondentes às lesões em que foram observadas células claras foram novamente processados e 22 lâminas foram coradas pela técnica do ácido periódico de Schiff (PAS) após digestão pela diástase e avaliadas quanto à presença de células mucosas. Foi realizada a análise estatística descritiva dos dados e estes foram representados na forma de gráficos e tabelas. Células mucosas foram observadas em 41,66% dos casos de cistos radiculares, 50% dos tumores odontogênicos ceratocísticos, 100% dos cistos dentígeros e 100% dos ameloblastomas unicísticos. Os resultados dessa pesquisa podem sugerir que fenômenos degenerativos e metaplásicos são de ocorrência usual no epitélio de cistos odontogênicos e de tumores odontogênicos císticos, podendo representar um fenômeno associado ao processo inflamatório crônico que, comumente, é observado nessas lesões, ou ser indicativo da multipotencialidade do epitélio odontogênico.

O tumor odontogênico queratocístico (TOQ) é uma neoplasia cística benigna originada de remanescentes epiteliais da odontogênese, que se destaca pela alta recorrência e eventual associação com a síndrome do carcinoma nevóide de células basais (SCNCB). O presente estudo buscou responder questionamentos relacionados à sua terapêutica cirúrgica e suprir a carência de pesquisas atuais sobre as lesões associadas à SCNCB, que são ainda mais recorrentes, analisando uma amostra formada por 40 TOQs primários. As variáveis de interesse determinaram grupos amostrais, que receberam análise dos tempos livres de recorrência por função Kaplan-Meier, comparação desses tempos pelo teste log-rank com nível de significância de 5% (p < 0,05) e determinação do risco acumulado para o evento nos primeiros cinco anos. Vinte e sete lesões foram tratadas por exérese (GE) e 13 receberam terapêutica descompressiva (GD). Tratamentos complementares ocorreram em 38 (95%) lesões, sendo ostectomia periférica isolada em 10 (GO) e combinada à solução de Carnoy em 28 (GC). Treze eram associadas à SCNCB (GS) e as demais (n = 27) representaram lesões não sindrômicas (GnS). No período de acompanhamento médio de 43,5 meses (12 102 meses), seis (15%) recorrências foram diagnosticadas. Não houve diferença significativa entre os tempos livres de recorrência nos grupos comparados (p > 0,05), nem expressividade do risco acumulado para o evento na terapêutica descompressiva (15,4%) e na associação com a SCNCB (12,5%). A aplicação da solução de Carnoy não aumentou a efetividade da ostectomia periférica, mas se relacionou com risco acumulado de recorrência de 0% ao final do quinto ano de acompanhamento pós-exérese nas lesões sindrômicas. Portanto: 1) a terapêutica descompressiva não aumentou o risco para recorrências; 2) a ostectomia periférica mostrou efetividade similar quando combinada à solução de Carnoy, pelo menos nas lesões não associadas à SCNCB; 3) o risco de recorrência das lesões associadas à SCNCB também foi controlado por tratamentos complementares. / The keratocystic odontogenic tumor (KOT) is a benign cystic neoplasm originating from odontogenic epithelial remnants which is highlighted by its high recurrence rate and occasional association with the nevoid basal cell carcinoma syndrome (NBCCS). The present study aimed to answer questions related to its surgical therapy and to fulfill the lack of recent researches over the lesions associated to the NBCCS, which are even more recurrent, analyzing a sample ok 40 primary KOTs. Variables of interest determined sample groups that underwent recurrence-free period analyses by Kaplan-Meier function, comparing these results by log-rank test with a significance level of 5% (p < 0.05) and determination of cumulative risk for the recurrence event within the first five years. Twenty seven lesions were treated by exeresis (GE) and 13 underwent decompressive therapeutic (GD). Complementary treatment occurred in 38 (95%) lesions being as isolated peripheral ostectomy in 10 (GO) and combined with Carnoys solution in 28 (GC). Thirteen were associated to NBCCS (GS) and the others (n = 27) represented non syndromic lesions (GnS). For the mean follow-up period of 43.5 months (12 102 months), six (15%) recurrences were diagnosed. There was no significant difference among recurrence-free periods for the compared groups (p > 0.05) or cumulative risk expression for the decompressive therapeutic (15.4%) or for the association with NBCCS (12.5%). Carnoys solution application did not increase the efficacy of the peripheral ostectomy but was related to the cumulative recurrence risk of 0% at the end of the fifth year of post-exeresis follow-up for syndromic lesions. Therefore: 1) the decompressive therapeutic did not increase the recurrence risk; 2) peripheral oostectomy demonstrated similar efficacy when combined to Carnoys solution, at least for lesions not associated to NBCCS; 3) the recurrence risk of lesions associated to NBCCS was also controlled by complementary treatments.

>Magister Scientiae - MSc / Odontogenic myxoma (OM) is one of the rare odontogenic tumours that affect the maxilo-facial regions. Skeletal myxomas are more common than soft tissue types in the facial regions. Odontogenic myxomas (OM) are non metastasizing tumours and therefore are considered benign. These lesions are known for their distinctive infiltrative nature which makes complete surgical removal a challenging task.Since the tumour occurs inside the bone and can reach a considerable size with little or no clinical manifestation, the radiologic examination remains the main method to determine the size and the extension of the tumour preoperatively.Aim of the study To assess the different imaging techniques which are currently in use for the diagnosis of the odontogenic myxomas.Materials and methods The images were retrieved from the library of the Department of Diagnostics and Radiology at the Tygerberg Oral Health Centre.Initially each of the imaging modalities was assessed independently to describe the imaging features of odontogenic myxoma on conventional radiograph,Computed Tomography (CT) and Magnetic Resonance Image (MRI). Secondly the imaging features of the three techniques were correlated and contrasted to determine the most valuable imaging modality in the diagnosis of the tumour.Results In this study we found that MRI was superior to other modalities in the ability to show and determine the true extension of the tumours. Therefore, MRI distinguished the tumour tissue from the surrounding structures and soft tissues.Myxomas were found to display characteristic patterns of growth on MRI. These patterns include lobulations and/or budding, nodulation and crevices formation.Moreover T2 weighted images deduced the contents of the tumour by emitting different signal intensities from the various components of the tumours.Additionally, characteristic pattern of contrast uptake differentiated the myxomatous, collagenous parts and presumed the nature of the trabeculae whether it is bony or fibrous.CT also showed the tumour and determined the subtle extension of the tumour into the adjacent structures and bone. Expansion and status of the cortical margin were reliably detected on CT. It also determined the pattern of growth in all tumours whether it is lobulation and/or budding, crevices formation or combination of them. In the present study this feature seemed to be a characteristic finding for all the tumours on CT. Moreover CT was able to compare densities of the tumours to surrounding muscles.Conventional radiography (CR) showed great limitations with regard to diagnostic abilities. Although it displayed the existence of the abnormality in all cases,conventional radiograph failed to detect margins and extension in most of the lesions. Therefore conventional radiograph is not reliable for presurgical assessment of the tumour or in differentiation the tumour from other benign and some malignant tumour. Conclusion In spite of the many limitations and shortcomings, conventional radiography remains the preliminary step in the diagnosis process. However digital imaging techniques provide images of great diagnostic value which is especially helpful in the diagnosis of odontogenic myxoma.

Zysten und zystenähnliche Erkrankungen sind häufig auftretende Krankheiten des Ober- sowie Unterkiefers. Das Ziel der durchgeführten Studie war es, die Prävalenz und die topografische Verteilung von Kieferzysten für eine Leipziger Population darzustellen. Dafür wurden aus 4245 oralpathologischen Fällen der Jahre 2000 bis 2010 jene herausgefiltert, die einen Bezug zur Zielstellung aufwiesen. Es wurden Daten von 1336 Fällen (31,5%) ermittelt und retrospektiv ausgewertet. Die Auswertung erfolgte an Hand folgender Merkmale: Alter, histologische Beurteilung, Geschlecht, Größe, Lokalisation, Vorliegen eines Rezidivs, sowie entzündliche oder regressive Veränderung. Mit 932 Fällen stellten radikuläre Zysten die größte Gruppe (69,8%), gefolgt von follikulären Zysten (n=257; 19,2%), keratozystischen odontogenen Tumoren (n=62; 4,6%) sowie Residualzysten (n=54; 4,0%). Jeweils mit Anteilen kleiner als 1% wurden die folgenden Entitäten festgestellt: Ameloblastome (n=12), laterale parodontale Zysten (n=5), solitäre Knochenzysten (n=5), nasopalatinale Zysten (n=3), aneurysmatische Knochenzysten (n=2), paradentale Zysten (n=2), sowie Eruptionszysten als auch glanduläre odontogene Zysten (jeweils n=1). Mit 62,4% aller Patienten waren Männer signifikant häufiger betroffen (833 zu 502). 52,5% aller Zysten traten im Unterkiefer auf, damit signifikant öfter als im Oberkiefer (701 zu 603 Fälle). Die Altersspannweite reichte von einem bis zu 92 Jahren. Durchschnittliche trat eine Zyste erstmals mit 42,86 ± 17,30 Jahre (n=1335) auf. Weiterhin betrug die Durchschnittsgröße einer Zyste 1,17 ± 0,9 cm (n=1327). In 1101 Fällen (82,5%) konnte eine entzündliche Komponente histologisch nachgewiesen werden, vordergründig bei radikulären (n=932) sowie follikulären Zysten (n=106). Rezidive einer Erkrankung wurden in 17 Fällen beschrieben, besonders oft in keratozystischen odontogen Tumoren (n=8) sowie Ameloblastomen (n=4). Regressive Veränderungen konnten an 9 Zysten festgestellt werden, mit 4 Fällen am häufigsten bei keratozystischen odontogenen Tumoren. Die Prävalenz als auch die Verteilung der Kieferzysten in Leipzig zeigte sich in weiten Teilen sehr ähnlich zu den aus anderen Populationen.