Presencia de lesiones quísticas en sacos pericoronarios de terceros molares mandibulares / Presence of cystic lesions in pericoronary sacs of mandibular third molars

Introducción: a pesar de que un tercer molar no erupcionado repre- senta un riesgo de formación quística, la práctica clínica desestima el análisis histopatológico de los folículos de dichos molares. Objetivo: identificar la frecuencia de lesiones quísticas en los sacos pericoronarios de terceros molares mandibulares. Material y métodos: estudio des- criptivo, transversal, analítico y observacional, en donde se incluyeron sacos pericoronarios de terceros molares mandibulares para su análisis histopatológico, descripción de características clínico-radiográficas y su asociación con la presencia de cambios histológicos o lesiones quís- ticas. Resultados: se incluyeron 48 muestras de sacos pericoronarios, la histopatología de los sacos pericoronarios mostró que 83.3% tenían algún tipo de alteración: 13 quistes paradentales (27.1%), cuatro quistes dentígeros (8.3%), 12 folículos hiperplásicos (25.0%) y 11 folículos inflamados (22.9%). La presencia de lesiones quísticas en la población fue de 35.4%. Se detectó asociación estadísticamente significativa entre el sexo y la presencia de lesiones quísticas (p = 0.039) y entre el nivel de erupción y la presencia de cambios histológicos (p = 0.046). Con- clusiones: la frecuencia de lesiones quísticas o cambios histológicos en folículos de terceros molares mandibulares es alta, principalmente en molares parcialmente erupcionados o submucosos y sin importar la ausencia de sintomatología o alteraciones radiográficas (AU))

Introduction: although a non-erupted third molar represents a risk of cystic formation; clinical practice rejects the histopathological analysis of the follicles of said molars. Objective: identify the frequency of the histopathological changes in pericoronary sacs of mandibular third molars. Material and methods: descriptive cross- sectional, observational and analytic study, where pericoronary sacs of mandibular third molars were included for histopathological analysis, description of clinical-radiographic characteristics and their association with the presence of histological changes or cystic lesions. Results: 48 samples of pericoronary sacs were included, the histopathology of the pericoronary sacs showed 83.3% had some type of alteration: 13 paradental cysts (27.1%), four dentigerous cysts (8.3%), 12 hyperplastic follicles (25.0%) and 11 inflamed follicles (22.9%). The presence of cystic lesions in the population was 35.4%. A statistically significant association was detected between sex and the presence of cystic lesions (p = 0.039); and between the level of eruption and the presence of histological changes (p = 0.046). Conclusions: the frequency of cystic lesions or histological changes in mandibular third molar follicles is high, mainly in partially erupted or submucosal molars and regardless of the absence of symptoms or radiographic alterations (AU)

Should the solid variant of odontogenic keratocyst and keratoameloblastoma be classified as the same entity? A clinicopathological analysis of nine cases and a review of the literature.

The solid variant of odontogenic keratocyst (SOKC) is an extremely rare odontogenic lesion, which remains poorly defined even in the 2017 World Health Organization odontogenic tumour classification. It is difficult to distinguish between SOKC and so called keratoameloblastoma (KAB), both rare lesions that have similarities in clinical, histological and biological characteristics. Here, we report clinicopathological data and results of molecular analysis of nine cases with a literature review. First, they were compared to previously reported cases of SOKC and/or KAB, and many overlaps were found in clinical and pathological characteristics. Second, we performed PCR analysis for BRAF V600E mutation. Although ameloblastoma-like epithelia were often encountered, none exhibited BRAF V600E mutation, which has been reported to occur frequently in ameloblastomas but not in odontogenic keratocysts (OKCs). One of two cases of SOKC in the present series from which fresh frozen tissue specimens were available was found to harbour PTCH1 mutations, indicating that these were more likely to be a subtype of OKC. Moreover, we also examined the differences between SOKC and primary intraosseous carcinoma (PIOC) with regard to the expression of cytokeratins (pan-CK, CK5/6, CK7, CK8/18, CK10, CK14 and CK19), p53 and Ki-67. The proportions of p53-and Ki-67-positive cells were significantly higher in PIOC than in SOKC. These findings suggest that immunostaining for p53 and Ki-67 would be useful to differentiate between SOKC and PIOC. We also conducted a review of SOKC and KAB cases reported in the English language literature.

The World Health Organization Classification of Odontogenic Lesions: A Summary of the Changes of the 2017 (4th) Edition.

The 4th edition of the World Health Organization (WHO) Classification of Head and Neck Tumors was published in January 2017. The edition serves to provide an updated classification scheme, and extended genetic and molecular data that are useful as diagnostic tools for the lesions of the head and neck region. This review focuses on the most current update of odontogenic cysts and tumors based on the 2017 WHO edition. The updated classification has some important differences from the 3rd edition (2005), including a new classification of odontogenic cysts, 'reclassified' odontogenic tumors, and some new entities.

Reclassification and treatment of odontogenic keratocysts: A cohort study.

The odontogenic keratocyst (OKC) is a recurrent cyst that has been recently reclassified from an odontogenic tumor to an odontogenic cyst. The aim of the present study was to investigate its treatment and address issues related to its association with nevoid basal cell carcinoma syndrome (NBCCS). Lesions from the cohort of patients included in the present study consisted of 40 OKCs, of which 27 lesions were treated by enucleation (GE) and 13 underwent decompression (GD). Complementary treatment occurred in 38 (95%) lesions, of which 10 underwent isolated peripheral ostectomy (GO) and 28 underwent peripheral ostectomy combined with Carnoy's solution (GC). Thirteen lesions were associated with NBCCS (GS), while the others (n=27) were non-syndromic lesions (GnS). The recurrence-free periods (RFP) in the sample groups were compared using the Kaplan-Meier function and log-rank test at a significance level of 5% (p < 0.05) and were used to calculate the cumulative risk of recurrence (CRR) in each postoperative year. During the follow-up period, which had a mean of 43.5 months (range: 12-102 months), six (15%) recurrences were diagnosed. There was no significant difference among the RFP for the compared groups (p > 0.05) or increased CRR for the decompression (15.4%) over five years. Application of Carnoy's solution did not increase the efficacy of the peripheral ostectomy, but was related to a CRR of 0% for the syndromic lesions over five years. Therefore, 1) decompression did not increase the recurrence risk; 2) peripheral ostectomy demonstrated a similar efficacy as the combination with Carnoy's solution; 3) the association of NBCCS did not seem to significantly influence OKC recurrence; and 4) syndromic lesions seem to behave in the same manner as non-syndromic lesions when submitted to complementary treatments.

Bi-maxillary dentigerous cyst in a non-syndromic child - review of literature with a case presentation.

Dentigerous cysts are the most common developmental odontogenic cysts of the jaw, which usually occur in the second and third decade of life. It is most frequently associated with impacted mandibular third molar teeth and impacted canines. Bilateral/multiple dentigerous cysts are rare and typically associated with developmental syndromes. Non-syndromic dentigerous cyst occurring bilaterally or involving both arches at the same time is very rare. Here, we discuss the review of literature with a case of unusual occurrence of non-syndromic bi-maxillary dentigerous cysts in a child.

Tumor odontogénico queratoquístico en seno maxilar: reporte de un caso clínico / Keratocystic odontogenic tumor in the maxillary sinus: report of a clinical case

El tumor odontogénico queratoquístico, es una patología que se encuentra asociada a la retención de un órgano dentario, en especial al tercer molar, es reconocido por su potencial destructivo y extenso, erosionando placas corticales que envuelven mucosa y tejidos blandos, la etiología del tumor odontogénico queratoquístico está probablemente relacionada con el desarrollo de la lámina dental (o restos de Serres) y con una mayor recidiva dentro de los tumores odontogénicos, siendo motivo de su reclasificación en el 2005 por la OMS. Se presenta casoclínico de un tumor odontogénico queratoquístico en el seno maxilarderecho, se exponen los métodos utilizados para la exploración clínica,radiológica y el tratamiento quirúrgico elegido.

The keratocystic odontogenic tumor is a condition associated withtooth retention, particularly of the third molar. It is recognized as beingpotentially highly destructive, by eroding cortical plates overlying theoral mucosa and soft tissues. The etiology of keratocystic odontogenictumor is probably related to the development of the dental lamina (orremains of Serres) and the recurrence rate is high compared to that ofother odontogenic tumors, the reason for their reclassifi cation by theWHO in 2005. We present a clinical case of a keratocystic odontogenictumor in the right maxillary sinus, including an explanation of themethods used for clinical and radiological examination, and the chosensurgical treatment.

Prevalence profile of odontogenic cysts and tumors on Brazilian sample after the reclassification of odontogenic keratocyst.

PURPOSE: The aim of this study was to evaluate the impact of the reclassification of odontogenic keratocyst (OKC) as a tumor on the prevalence profile of odontogenic cysts (OCs) and odontogenic tumors (OTs). STUDY DESIGN: Two referral Oral and Maxillofacial Pathology services in Brazil were evaluated. All cases diagnosed as OCs or OTs were selected and classified according to the 1992 WHO-classification (cases before 2005 WHO classification of tumors excluding OKC) and the 2005 WHO classification of tumors, going forward including cases of odontogenic keratocyst tumor (KCOT). The frequency and prevalence of OCs and OTs were compared before and after the reclassification. RESULTS: Among 27,854 oral biopsies, 4920 (17.66%) were OCs and 992 (3.56%) were OTs. The prevalence of OTs before 2005 WHO classification of tumors was 2.04%, while the prevalence after 2005 WHO classification was 11.51% (p < 0.0001). Before 2006, the most frequent tumor diagnosed was odontoma with 194 cases (39.67%), and after 2005 WHO classification of tumors the KCOT was the most frequent with 207 cases (41.07%). CONCLUSIONS: The increase in the prevalence of OTs after 2005 WHO is related to the improvement of pathology services and to the inclusion of KCOT in the OTs group.

Reclassification and treatment of odontogenic keratocysts: A cohort study

Abstract: The odontogenic keratocyst (OKC) is a recurrent cyst that has been recently reclassified from an odontogenic tumor to an odontogenic cyst. The aim of the present study was to investigate its treatment and address issues related to its association with nevoid basal cell carcinoma syndrome (NBCCS). Lesions from the cohort of patients included in the present study consisted of 40 OKCs, of which 27 lesions were treated by enucleation (GE) and 13 underwent decompression (GD). Complementary treatment occurred in 38 (95%) lesions, of which 10 underwent isolated peripheral ostectomy (GO) and 28 underwent peripheral ostectomy combined with Carnoy's solution (GC). Thirteen lesions were associated with NBCCS (GS), while the others (n=27) were non-syndromic lesions (GnS). The recurrence-free periods (RFP) in the sample groups were compared using the Kaplan-Meier function and log-rank test at a significance level of 5% (p < 0.05) and were used to calculate the cumulative risk of recurrence (CRR) in each postoperative year. During the follow-up period, which had a mean of 43.5 months (range: 12-102 months), six (15%) recurrences were diagnosed. There was no significant difference among the RFP for the compared groups (p > 0.05) or increased CRR for the decompression (15.4%) over five years. Application of Carnoy's solution did not increase the efficacy of the peripheral ostectomy, but was related to a CRR of 0% for the syndromic lesions over five years. Therefore, 1) decompression did not increase the recurrence risk; 2) peripheral ostectomy demonstrated a similar efficacy as the combination with Carnoy's solution; 3) the association of NBCCS did not seem to significantly influence OKC recurrence; and 4) syndromic lesions seem to behave in the same manner as non-syndromic lesions when submitted to complementary treatments.

Cistos odontogênicos e não odontogênicos diagnosticados no laboratório de patologia oral da UFRJ em um período de 30 anos / Odontogenic and non-odontogenc cysts diagnosed in oral pathology laboratory of UFRJ in a period of 30 years

Os cistos odontogênicos e não-odontogênicos são observados somente nos ossos gnáticos e casuísticas de diferentes regiões têm sido publicadas na literatura de língua inglesa. O objetivo deste trabalho foi determinar a frequência dos cistos odontogênicos e não-odontogênicos diagnosticados no Laboratório de Patologia Oral da UFRJ entre os anos de 1984 até 2015. Essas lesões foram obtidas após revisão dos arquivos da instituição. As características avaliadas foram: (1) tipo de cisto diagnosticado, (2) idade do paciente, (3) gênero do paciente e (4) localização da lesão. Os resultados da frequência de cada tipo de cisto e suas características clínicas foram apresentados de maneira descritiva considerando pacientes de todas as idades, pacientes adultos (maiores que 17 anos) e pacientes jovens (menores que 17 anos). Como resultado, 1141 cistos foram diagnosticados neste período, sendo 1026 (90%) odontogênicos e 105 (10%) nãoodontogênicos. Os cistos odontogênicos mais frequentes foram o cisto radicular (449 casos, 39,3%), cisto dentígero (195 casos, 17%) e o queratocisto odontogênico (147 casos, 12,8%). Os cistos não-odontogênicos mais frequentes foram o cisto do ducto nasopalatino (32 casos, 2,8%), cisto epidermóide (25 casos, 2,1%) e cisto de retenção de muco (17 casos, 1,4%). Os cistos odontogênicos e não-odontogênicos diagnosticas no laboratório de Patologia Oral da UFRJ parecem mostrar um perfil clinicopatológico semelhante ao encontrado em outros estudos do mundo, com poucas variações em relação à idade, gênero e localização preferencial. (AU)

Odontogenic and non-odontogenic cysts are observed only in the gnathic and casuistic bones of different regions have been published in the English-language literature. The objective of this study was to determine the frequency of odontogenic and non-odontogenic cysts diagnosed in the Oral Pathology Laboratory of the Federal University of Rio de Janeiro between 1984 and 2015. These lesions were obtained after reviewing the institution's files. The evaluated features were (1) type of microscopically diagnosed cyst, (2) age, (3) gender, and (4) location of the cyst. The frequency of each type of cyst and its clinical features were descriptivelly presented considering patients of all ages, younger than 17 years, and older than 17 years. One thousand one hundred and forty one cysts were diagnosed in this period, 1026 (90%) of them were odontogenic and 105 (10%) were non-odontogenic. The most frequent odontogenic cysts were radicular cyst (449 cases, 39,3%), dentigerous cyst (195 cases, 17%), and odontogenic keratocyst (147 cases, 12,8%). The most frequent non-odontogenic cyst were the nasopalatine duct cyst (32 cases, 2,8%), epidermoid cyst (25 casos, 2,1%) e mucus retention cyst (17 cases, 1,4%). The odontogenic and non-odontogenic cysts diagnosed in the Oral Pathology Laboratory of the UFRJ seem to show a clinicopathological profile similar to that found in other studies in the world, with few variations in relation to age, gender and preferential location. (AU)

Quiste odontogénico ortoqueratinizado: reporte de un caso / Orthokeratinized odontogenic cyst: report of a case

El quiste odontogénico ortoqueratinizado es un quiste de desarrollo poco común de los maxilares. Descrito en 1956 por Philipsen como una variante del queratoquiste odontogénico (tumor odontogénico queratinizante) y posteriormente identifi cado como una entidad totalmente aparte por Wrigth, sigue siendo hoy en día una lesión en controversia. En este trabajo se reporta el caso de un paciente masculino de 15 años de edad que acude al Servicio de Cirugía Maxilofacial del Hospital Regional®Lic. Adolfo López Mateos¼, ISSSTE, el cual es diagnosticado como un quiste odontogénico ortoqueratinizado. Tener una adecuada ruta clínica para el diagnóstico clínico, complementado por imagen, y sobre todo contar con el resultado de la biopsia incisional son pasos fundamentales para poder diagnosticar y no sobretratar padecimientos que, con procedimientos menos invasivos y agresivos, tienen mejor pronóstico...

Análise retrospectiva das lesões do complexo oral e maxilofacial do Serviço de Cirurgia oral do Hospital Universitário Clementino Fraga Filho: um estudo retrospectivo de 24 anos / Retrospective analysis of injuries of the oral complex and maxilofacial in Oral Surgery Service of the Hospital Universitário Clementino Fraga Filho: a study retrospective of 24 years

Os estudos epidemiológicos podem auxiliar na identificação da prevalência das lesões em uma determinada população, assim como na coleta de dados relativos a localização, idade, gênero e saúde geral do paciente, bem como hábitos nocivos existentes, e possíveis fatores etiológicos associados. Na literatura, os estudos epidemiológicos das doenças de boca exibem, em sua maioria, uma alta prevalência de lesões benignas de mucosa, principalmente do tipo hiperplásicas, assim como mucoceles, e alterações inflamatórias periapicais. No entanto, a real prevalência das lesões pode variar de acordo com a idade dos pacientes e da origem dos casos. O objetivo deste trabalho foi identificar a prevalência e as características sócio- demográficas de lesões orais dos pacientes encaminhados para tratamento cirúrgico no serviço de Cirurgia Oral do Hospital Universitário Clementino Fraga Filho (HUCFF), da Universidade Federal do Rio de Janeiro. O período de estudo compreendeu de 1989 a 2013, perfazendo 24 anos As lesões diagnosticadas foram classificadas de acordo com a sua natureza. Os dados coletados foram analisados levando-se em conta os valores absolutos e percentuais. Dos 328 casos da amostra, 159 (48,5%) eram pacientes do sexo feminino e 169 (51,5%) pacientes do sexo masculino, e a média de idade geral foi de 34,26 anos. Os cistos e tumores odontogênicos de desenvolvimento ocorreram mais comumente com 154 casos, representando 47,0%. As doenças da polpa e do periápice e as lesões intra-ósseas não odontogênicas foram responsáveis por 18,9% e 10,7% das lesões, respectivamente. Dezenove casos (5,7%) eram lesões hiperplásicas; 16 (4,9%) eram lesões de glândulas salivares; 13 (4%) eram lesões malignas; e 13 (4,0%) eram cistos não- odontogênicos. Dez casos (3,0%) eram de lesões com diagnóstico inconclusivo, e as neoplasias benignas foram as menos comumente diagnosticadas, com apenas 6 casos (1,8%). Levando-se em consideração as lesões de maior prevalência, o cisto radicular foi a patologia mais comumente encontrada representando 16,8% da amostra, seguido do cisto dentígero (15,3%), do ameloblastoma (10,7%), do tumor odontogênico ceratocístico (9,5%) e dos odontomas (5,5%). (AU)

Epidemiological studies can assist in identifying the prevalence of oral lesions in a given population. Other information that can be collected is data on affected sites, patient´s age and gender and overall health, the presence of hazardous habits and associated etiological factors. In the literature, epidemiological studies of oral diseases nearly always exhibit a high prevalence of mucosal benign hyperplastic lesions, as well as mucoceles and periapical inflammatory lesions. However, the actual prevalence of lesions may depend on patient´s age range and in the origin of the cases. The aim of this study was to determine the prevalence and socio-demographic characteristics of odontogenic and non- odontogenic lesions of patients referred for surgical treatment at the Oral Surgery Service of the Clementino Fraga Filho University Hospital (HUCFF), of the Federal University of Rio de Janeiro. The study period totalized 24 years, from 1989 to 2013. The lesions were classified according to their nature. The collected data was analyzed taking into account the absolute values and percentages. Of the 328 sample cases, 159 (48.5%) were female patients and 169 (51.5%) male patients, and the average age was of 34.26 years. Dvelopment Odontogenic Cysts and Tumors occurred more commonly with 154 cases, representing 47.0% of the study group. Pulpal and periapical diseases and non-odontogenic bone lesions accounted for 18.9% and 10.7% cases, respectively. Nineteen cases (5.7%) were hyperplastic lesions; 16 (4.9%) were salivary glands lesions; 13 (4%) were malignant neoplasms; and 13 (4.0%) were nonOdontogenic cysts. Ten cases (3.0%) were represented by lesions with inconclusive diagnosis. Benign neoplasms were the least commonly diagnosed cases, with only 6 tumors (1.8%). Taking into consideration the lesions of higher prevalence, the periapical cyst was the most commonly found oral disease representing 16.8% of the sample, followed by the dentigerous cyst (15.3%), the ameloblastoma (10.7%), the keratocystic odontogenic tumor (9.5%) and the odontomas (5.5%). (AU)

Tumor odontogénico queratoquístico: revisión bibliográfica y presentación de un caso / Keratocystic odontogenic tumor: review of the literature and report of a case

La Organización Mundial la Salud (OMS) a través del Centro Internacional de Referencia de los Tumores Odontogénicos en su última clasificación 2005, ha decidido incluir al Quiste Odontogénico queratoquístico Paraqueratinizado dentro del grupo de los Tumores Odontogénicos, como Tumor Odontogénico Queratoquístico y ha permanecido el Quiste Odontogénico Queratoquístico Ortoqueratinizado, como una entidad se-parada dentro de los Quistes Odontogénicos ya existente, es decir uno pasa a ser una neoplasia benigna y otro una entidad quística.Los autores presentamos un caso clínico quirúrgico de un tumor Odontogénico Queratoquístico...

Ameloblastoma uniquístico plexiforme: a propósito de un caso / Plexiform unicystic ameloblastoma: a propos of a case

El ameloblastoma es un tumor odontogénico benigno de origen epitelialcon estroma fi broso maduro sin ectomesénquima odontogénico, decomportamiento localmente agresivo e infi ltrante con alta capacidad de recidiva. Representa entre 11 y 13 por ciento de los tumores odontogénicosmandibulares y 1 por ciento de los tumores y quistes maxilomandibulares. El tratamiento debe orientarse de acuerdo con el potencial del tumor,las características del crecimiento según su variable clínica y el tipo histológico. Debe ser un tratamiento que asegure un mejor pronóstico para el paciente

The ameloblastoma is a benign odontogenic tumor of epithelial origin with mature fi brous stroma, without odontogenic ectomesenchyme. It exhibits locally aggressive and invasive behavior, with a high level of recurrence. Ameloblastomata account for between 11 and 13% of mandibular odontogenic tumors, and 1% of maxillo-mandibular tumors and cysts. Treatment should be guided by the potential of the tumor and its growth characteristics based on the clinical variable and histological type, the preferred treatment being that which ensures the best prognosis for the patient.

Cystic Conditions of the jawbones: A Review of Early Classification Systems.

Cystic conditions of the jawbones were recognized long before the establishment of the American Academy of Oral Pathology (AAOP) in 1948, but it was around this time when they were studied, characterized, and classified. The history of the classification systems implemented by oral pathologists to study the cystic conditions of the maxillary bones is intimately related with the birth of oral and maxillofacial pathology as a specialty of dentistry. The purpose of this paper is to review the early classification systems proposed for the cystic conditions of the jawbones.

Cisto dentígero de grandes dimensões: acesso intraoral e reabilitacão / Dentigerous cvst: intra-oral occess ond rehobilitotion

O cisto dentígero é uma lesão ósseo-destrutiva, classificada como cisto odontogênico de de­ senvolvimento de etiopatogênia desconhecida. É o segundo cisto odontogênico mais frequente nos maxilares. Apresenta radiograficamente imagem radiotransparente, unilocular, observados geralmente em exames de rotina ou pelo atraso de erupção de um dente. Acomete indivídu­ os nas três primeiras décadas de vida, apresenta crescimento lento e indolor. As modalidades terapêuticas mais utilizadas são a marsupialização, descompressão e enucleação, porém o tra­ tamento varia conforme a idade, tamanho do cisto, proximidade com estruturas anatômicas e condições clinicas do dente envolvido. Sendo assim o objetivo desse artigo é relatar um caso clinico com inusitada reabsorção radicular desde o seu diagnostico até a fase de reabilitação e preservação...

The dentigerous cyst is abone destructive lesions classified as odontogenic cyst develo­ pment of unknown etiopathogenesis. It is the second most common odontogenic cyst in the jaws. Presents radiographically radiolucent image, unilocular usually seen in routine screening or the eruption delay of a tooth. Affects individuais in the first three decades of life, its growth is slow and painless. The most common therapeutic modalities are marsupialization, decompres­ sion and enucleation, but treatment varies according to age, cyst size, proximity to anatomical structures and clinical conditions of the involved tooth. Thus the aim of this paper is to report a clinical case since its diagnosis until the phase of rehabilitation and proservation...

Odontogenic tumors, WHO 2005: where do we go from here?

As our knowledge of disease improves, its classification continually evolves. The last WHO classification of odontogenic tumors was 9 years ago and it is time for revision. We offer the following critique as a constructive, thought provoking challenge to those chosen to provide contemporary insight into the next WHO classification of odontogenic cysts, tumors, and allied conditions.

Automated classification of four types of developmental odontogenic cysts.

Odontogenic cysts originate from remnants of the tooth forming epithelium in the jaws and gingiva. There are various kinds of such cysts with different biological behaviours that carry different patient risks and require different treatment plans. Types of odontogenic cysts can be distinguished by the properties of their epithelial layers in H&E stained samples. Herein we detail a set of image features for automatically distinguishing between four types of odontogenic cyst in digital micrographs and evaluate their effectiveness using two statistical classifiers - a support vector machine (SVM) and bagging with logistic regression as the base learner (BLR). Cyst type was correctly predicted from among four classes of odontogenic cysts between 83.8% and 92.3% of the time with an SVM and between 90 ± 0.92% and 95.4 ± 1.94% with a BLR. One particular cyst type was associated with the majority of misclassifications. Omission of this cyst type from the data set improved the classification rate for the remaining three cyst types to 96.2% for both SVM and BLR.