Segmental Odontomaxillary Dysplasia: A Case Report and Review of the Literature.

Segmental odontomaxillary dysplasia (SOD) is a rare and unusual nonhereditary developmental disorder that affects one side of the maxilla, impacting the hard tissue, soft tissue, and dentition in the affected area. It most frequently presents with enlargement of the gingival and osseous tissue of the affected side and hypodontia of the involved quadrant. Cutaneous irregularities of the impacted area are also common. We report a case of SOD arising in the right maxilla of a three-year-old female. Our report and review of the literature highlight the clinical, radiographic, and histopathologic characteristics of SOD, as well as the management of patients and the proposed etiologies of its pathogenesis.

Regional odontodysplasia diagnosed and treated via multidisciplinary approach: a case report.

Regional odontodysplasia (RO) is a rare non-hereditary dental anomaly associated with dysplasia. Its etiology remains unclear but is known to affect both the mesodermal and ectodermal dental components, as well as deciduous and permanent dentitions. Its young age of onset and complexity has great physical and psychological impact on the affected patients. However, the clinical management of RO remains unified without standardized treatment guidelines. Thus, this study aimed to report an RO case, the first from Jiangxi Province, China, and discuss its clinical diagnosis and treatment to provide a reference to treat similar cases more effectively in the future.

Regional Odontodysplasia: A Systematic Review of Case Reports.

Regional odontodysplasia is a rare developmental disorder characterised by hypoplasia and hypomineralisation of enamel and dentin. Our systematic review aimed to organise the knowledge on localisation, symptomatology and treatment methods in patients with regional odontodysplasia based on case reports published in the databases PubMed, Scopus and Web of Science. Case reports were described in 28 different countries, considering 180 patients (including 91 females). Regional odontodysplasia occurs mainly in both deciduous and permanent dentition (66.1%). The affected teeth were observed more frequently in the maxilla (70.0%), especially on the left side (45.6%). The most common reported symptoms were ghost teeth, poorly developed buds, yellowish-brown colour of crowns and delayed eruption of permanent teeth in affected quadrants. The most popular treatment method was surgical treatment (78.6%) with subsequent prosthetic therapy (34.6%). Based on the review of cases, pathognomonic clinical and radiological signs can be found, however, it is difficult to reach a consensus on the choice of treatment method.

Regional Odontodysplasia Affecting the Maxilla.

Regional odontodysplasia (RO) is a rare dental anomaly of unknown etiology that can affect both deciduous and permanent dentition. RO is characterized by severe hypoplasia of enamel and dentin, and teeth affected are friable and more susceptible to caries and fractures. Most of the lesions occur in the anterior maxilla and correlation with clinical and radiographic features is essential to provide a correct diagnosis. The major criteria for diagnosis are predominantly based on radiography, which shows presence of large pulp chambers and a marked reduction in the radiopacity of enamel and dentin, making the distinction between these mineralized structures difficult. Early diagnosis is important to minimize future sequels and allow preventive or conservative treatment. The therapeutic approach of the RO should be based on the degree of severity of the anomaly and in the individual functional and aesthetic needs of each case. A classic case of RO affecting the maxilla is exemplified in this Sine Qua Non Radiology-Pathology article.

Odontodisplasia Regional y Agenesia de Premolares. Reporte de un Caso / Regional Odontodysplasia and Premolar Agenesis. Case Report

RESUMEN: La odontodisplasia regional (OR) es una alteración en el desarrollo, no hereditario y que afecta tanto la dentición temporal como la dentición definitiva. Involucra a los tejidos mesodérmicos y ectodérmicos de los dientes lo que es condescendiente con hallazgos clínicos, radiográficos e histológicos. Su etiología aun es desconocida y se presenta mayoritariamente en mujeres. Clínicamente puede afectar al maxilar, a la mandíbula o ambas arcadas pero generalmente solo se ve comprometida una ellas, principalmente el más afectado es el hueso maxilar. Radiográficamente se observa una pobre diferencia entre los tejidos del esmalte y la dentina, siendo tejidos menos radiopacos que su contraparte sana generando un aspecto descrito como "diente fantasma". Histológicamente se observan zonas hipocalcificadas del esmalte con un orden de prismas irregulares mientras que la dentina se observa con un número reducido de túbulos dentinarios y de consistencia más fibrosa en su zona coronal. El tratamiento de la OR es controversial ya que su incidencia es baja y la literatura al respecto no es clara. El objetivo de este manuscrito, fue reportar un caso de OR y revisar la literatura relacionada. Presentamos un caso de OR en una paciente de 12 años que presenta ausencia de los dientes 2.4, 2.5 y 2.6; restos radiculares y agenesia de los dientes 3.5 y 4.5. Se describirán sus aspectos clínicos, radiográficos e histológicos. Se realizó una búsqueda sistemática en las siguientes bases de datos: Clínical key, Science Direct, PubMed y SciELO.

ABSTRACT: Regional odontodysplasia (RO) is a variation in the development; it is not hereditary and it affects both deciduous and permanent dentition. It involves the mesodermal and ectodermal tissues of dental pieces, and coincides with clinical, radiographic and histological findings. Its etiology is still unknown and it reportedly occurs mostly in women. Clinically it can affect the maxilla, mandible or both arches but generally only one is compromised, mainly the maxilla which is affected the most. Radiographically there is limited difference between enamel and dentin tissue, which is less radiopaque than their healthy counterpart, generating an aspect described as "phantom tooth". Histologically hypocalcified areas of the enamel are observed with an irregular order of prisms while the dentine is observed with a reduced number of dentinal tubules and more fibrous consistency in the coronal area. RO treatment is controversial since its incidence is low and the literature on these events is not clear. The aim of this manuscript was to report a case of RO and review related literature. We present a case of RO in a 12-year-old patient who presents absence of parts 2.4.2.5 and 2.6; radicular remains and agenesis of parts 3.5 and 4.5. Its clinical, radiographic and histological aspects are described. A systematic search was carried out in the following databases: Clinical key, Science Direct, PubMed and SciELO.

Regional Odontodysplasia Crossing the Midline.

Regional odontodysplasia is a non-hereditary development dental anomaly involving epithelial and mesenchymal-derived dental tissues. The condition affects both primary and permanent teeth. Clinically, affected teeth are hypoplastic, soft upon probing, have a yellow-brown discoloration and present high susceptibility to caries. Radiographically, the teeth show enlarged pulp chambers, open apices and no clear differentiation between enamel and dentin. The reduced radiopacity of the enamel and dentin gave rise to the term ghost teeth. We present the case of a three-year-old boy diagnosed with regional odontodysplasia involving more than one quadrant, showing facial asymmetry and missing primary and permanent teeth.

Anomalías en el Desarrollo y Formación Dental: Odontodisplasia / Development Abnormalities and Dental Training: Odontodysplasia

El papel que desempeñan las alteraciones genéticas en el desarrollo dental es fundamental. Se ha descubierto que si no existe una correcta expresión del gen o se da una mutación de este, el individuo podría presentar ausencias o malformaciones de estructuras de la boca. Por esta razón se describe la forma en que se da el desarrollo de las estructuras dentales, teniendo en cuenta cómo las interacciones genética y ambiental influyen en su correcto desarrollo. Entre los genes involucrados se encuentran el PAX9 y el MSX1, que según recientes investigaciones son los implicados en las ausencias congénitas de estructuras dentarias o sus posibles alteraciones, teniendo en cuenta que la delación de estos genes o su mutación son factores hereditarios. Los genes odontogénicos PAX9 y MSX1, son genes homeóticos (homebox) que codifican para factores de transcripción y son responsables, durante la odontogénesis, de la expresión de genes asociados con la regulación espacial y temporal dentro del primer arco braquial. En determinado momento de la organogénesis pueden darse fallas en la expresión de los factores necesarios para la formación y buen desarrollo dental, causando anomalías como la Odontodisplasia Regional (OR), también denominada diente fantasma o detención localizada del desarrollo dental, la cual es una anomalía estructural del desarrollo, compleja y rara; parece ser el resultado de una o más mutaciones puntuales en el cromosoma 4 y 14. Se reportan dos casos donde se describen las características clínicas, radiográficas, y el seguimiento clínico.

The role of genetic alterations in tooth development is essential. It has been discovered that if there is a correct expression of the gene or there is a mutation of this, the individual could present absence or malformations of structures of the oral cavity or other body parts. For this reason we describe how given the development of dental structures, taking into account how genetic and environmental interactions influence their proper development. Among the genes involved are in the PAX9 and MSX1, which according to recent research are involved in congenital absence of dental structures or alterations, considering that the denunciation of these genes or the mutation is inherited. The odontogenic PAX9 and MSX1 genes are homeotic genes (homebox) that encode for transcription factors and are responsible, during odontogenesis, the expression of genes associated with spatial and temporal regulation within the first brachial arch. At some point during organogenesis may be flaws in the expression of the factors necessary for the formation and tooth development, causing among other abnormalities Regional Odontodysplasia (RO), also called ghost tooth or detention tooth dental development located, which is a structural anomaly development complex and rare; seems to be the result of one or more point mutations in the chromosome 4 and 14. In this report we show two cases with odontodysplasia where there are clinical and radiographic features of two patients with this anomaly, one of them has been made up and treatment, and the other begins his analysis stage.

Regional odontodysplasia: literature review and report of an unusual case located in the mandible.

The purpose of this report was to describe the clinical, radiological, and histopathological features of a case of regional odonto- dysplasia (RA) in a seven-year-old boy who was followed for approximately two years. The case is unusual in that the dysplasia occurred in the mandible, and there was a normal-appearing tooth within the lesion, suggesting that there may be local factors that determine susceptibility of individual teeth in RA. The diagnosis of RA was based on the typical features of "ghost" teeth and evidence of disrupted calcification characterized by psammomatous bodies, hypomineralization of enamel, and the presence of interglobular dentin. Sequential orthopantomograms provide evidence of delayed dental development.

Expressão de ADLH-1 e CD44 em lesões epiteliais displásicas e no carcinoma epidermóide intra-oral / Expression of ALDH-1 and CD44 in dysplastic epithelial lesions and intra-oral squamous cell carcinoma

O estudo das células-tronco cancerígenas (CTCs) durante o processo de malignização e no carcinoma epidermóide intra-bucal já instalado é essencial para um melhor entendimento de como essas células participam da formação e manutenção de uma neoplasia. Atualmente, a identificação de células com características de células tronco se dá principalmente através da expressão de marcadores celulares como o ALDH1 e o CD44. A proteína ALDH1 é responsável pela oxidação de aldeídos intracelulares e vem sendo utilizada para o isolamento de CTCs em inúmeros canceres incluindo casos de cabeça e pescoço. A proteína CD44 é uma glicoproteína envolvida na adesão e migração celular, também participa do processo de metástase e já foi associada às CTCs. Nesse trabalho, a expressão dessas proteínas foi analisada em 45 casos de displasias epiteliais e 13 casos de carcinomas epidermóide intra-bucais. As lesões displásicas foram classificadas em casos leves (19), moderados (18) e intensos (8) e foram também divididas em casos de baixo risco (22) e alto risco de transformação maligna (23). A expressão imunohistoquímica para a ALDH1 foi encontrada predominantemente na camada basal em 16 casos de displasias epiteliais e em 7 carcinomas epidermóides, com a marcação difusa pela epitélio neoplásico. A expressão imunohistoquímica de CD44 foi encontrada em 42 displasias epiteliais e em 12 carcinomas epidermóides, sendo que nas displasias, a expressão ocorreu predominantemente na camada basal do epitélio e no carcinoma epidermóide a expressão foi disseminada. Ambos marcadores exibiram aumento de expressão com a evolução do grau das displasias.

The study of cancer stem cells (CTCs) in the process of malignant transformation and intra-oral squamous cell carcinoma already installed is essential for a better understanding of how these cells participate in the formation and maintenance of a neoplasm. Currently, identification of cells with characteristics of stem cells is primarily through the expression of cell markers such as CD44 and ALDH1. The ALDH1 protein is responsible for the oxidation of intracellular aldehydes and has been used for the isolation of CTCs in numerous cancers including head and neck cases. The CD44 protein is a glycoprotein involved in cell adhesion and migration, also participates in the process of metastasis and has been associated with CTCs. In this work, the expression of these proteins was analyzed in 45 cases of epithelial dysplasia and 13 cases of intraoral squamous cell carcinomas. The dysplastic lesions were classified as mild (19), moderate (18) and intense (8) cases and were also divided into low-risk cases (22) and high risk of malignant transformation (23). The immunohistochemical expression for ALDH1 was found predominantly in the basal layer in 16 cases of epithelial dysplasia and squamous cell carcinoma in 7, with diffuse labeling by neoplastic epithelium. Immunohistochemical expression of CD44 was found in 42 epithelial dysplasias and 12 squamous cell carcinomas, and in dysplasias, the expression occurred predominantly in the basal layer of the epithelium and in squamous cell carcinoma expression was widespread. Both markers showed increased expression with the evolution of the degree of dysplasia.

Análise histopatológica de lesões leucoqueratósicas da mucosa oral avaliadas pelos exames de luminescência, cromoscopia e microscopia confocal reflectante / Histological analysis identified and assessed by tests of luminescence, chromoendoscopy and confocal reflectance leukokeratosis lesions

O câncer de mucosa oral é um problema de saúde pública, com maior incidência em homens acima de 50 anos. Uma das manifestações clínicas mais precoces do câncer da mucosa oral são as lesões leucoqueratósica. O aspecto clínico não homogêneo e o tamanho maior de 200mm2, em mucosa não queratinizada como a do assoalho da boca e ventre da língua, são aspectos que implicam na possibilidade de evolução da lesão. A dificuldade do diagnóstico das lesões precoces está na seleção do local a ser biopsiado principalmente frente a lesões extensas e heterogêneas. O objetivo desta pesquisa é avaliar se a utilização do exame clínico juntamente com os métodos auxiliares de diagnóstico das lesões leucoqueratósica da mucosa oral (VELscope®, Azul de toluidina e Solução de lugol) contribui para uma maior precisão do diagnóstico de displasias nestas lesões quando comparado ao histopatológico. E, identificar os padrões morfológicos destas lesões quando avaliadas por meio da microscopia confocal reflectante. Foram selecionados 30 pacientes, maiores de 18 anos, portadores de lesão clínica compatível com leucoplasia oral triados no ambulatório da disciplina de Estomatologia Clínica da Faculdade de Odontologia da Universidade de São Paulo e que precisavam ser submetidos à biópsia para o estabelecimento do diagnóstico final. Foram realizados os testes de Azul de Toluidina, Solução de Lugol, VELscope®, microscopia confocal reflectante e posteriormente, a biópsia incisional para obtenção do diagnóstico final. Os pacientes incluídos possuíam média de idade 60,66 anos, sendo 70% (21/30) do gênero feminino e 30% (9/30) do gênero masculino. O tabagismo foi relatado por 16,7% (5/30) dos pacientes, sendo 60% (3/5) homens. A associação do tabagismo e etilismo foi relatada em 10% (3/30) dos pacientes, o tabagismo isoladamente por 6,6% (2/30) e o de etilismo por 3,3%(1/30)...

Cancer of the oral mucosa is a public health problem, with higher incidence in men above 50 years. One of the earliest manifestations of cancer of the oral mucosa lesions are leukokeratosis. The inhomogeneous clinical aspect and the larger size of 200mm2 in non-keratinized mucosa as the floor of the mouth and constipation of the tongue, are aspects that imply the possibility of evolution of the lesion. The difficulty of diagnosis of early lesions is in the selection of the site to be biopsied primarily against large and heterogeneous lesions. The objective of this research is to evaluate the use of clinical examination along with diagnostic aids leucoqueratósica of oral lesions (VELscope ®, Toluidine blue and Lugol solution) methods contributes to greater accuracy of diagnosis of dysplasia in these lesions when compared the histopathological. And identify the morphological patterns of these lesions when evaluated by reflectance confocal microscopy. 30 patients older than 18 years, with clinical lesion compatible with oral leukoplakia screened in the outpatient discipline of Clinical Dentistry, Faculty of Dentistry, University of São Paulo and that needed to be biopsied to establish the final diagnosis were selected. Tests toluidine blue, Lugol's solution, VELscope ®, reflectance confocal microscopy (RCM) and subsequently, incisional biopsy to obtain the final diagnosis were performed. Patients enrolled had a mean age 60.66 years, 70% (21/30) were female and 30% (9/30) were male. Smoking was reported by 16.7% (5/30) of patients, 60% (3/5) homens.A association of smoking and alcohol use was reported in 10% (3/30) of patients, smoking alone by 6.6% (2/30) and of alcoholism by 3.3% (1/30)...

Regional odontodysplasia. A literature review and three case reports.

AIM: The purpose of this article is to report some unusual characteristics related to gender, location and manifestations of severe Regional Odontodysplasia detected in three subjects. Regional Odontodysplasia is a rare disturbance of dental development whose aetiology is still unknown. Anomalies involve enamel, dentin, pulp and dental follicle causing atypical structure, colour, shape, size and eruptive disturbances of the affected teeth. Its early onset may lead to craniofacial development disturbances. CASES REPORTS: This article reports three cases with unusual characteristics observed in male children who were assisted by a paediatric dentist. Generally the disease affects one hemiarch and it is very rare that it crosses the midline as in one of the presented cases. Regional Odontodysplasia has been predominantly described in the maxilla and in women, however these three cases are in boys and two of them occured in the mandible. CONCLUSION: Regional Odontodysplasia is a rare disease, causing severe dental, growing and craniofacial development anomalies. Treatment needs to be personalised, aiming at preservation of the affected teeth taking into account their risk to develop severe infections. Parents should be made aware of the need for an extensive follow-up.

Early diagnosis of regional odontodysplasia in an infant.

Regional odontodysplasia is a rare and significant dental malformation. It is a dental alteration of unknown etiology, involving both mesodermal and ectodermal dental components, which present clinical, radiographic, and histologic features. This article reports a clinical case of a 10-month-old child who was diagnosed with regional odontodysplasia in the maxilla, confirmed by radiographic examination, with a follow-up of 5 years. The clinical, radiographic, and histologic features were reviewed.

Caracterização da displasia fibrosa em imagens de tomografia computadorizada helicoidal empregando a análise da lacunaridade / Characterization of fibrous dysplasia in helical computed tomography images employing the analysis of lacunarity

A displasia fibrosa é uma alteração de desenvolvimento caracterizada pela substituição do osso normal por tecido conjuntivo denso e trabéculas ósseas imaturas, geralmente encontrada em adolescentes e adultos jovens. Uma alteração genética que envolve a proteína Gs-alfa parece ser a base do processo. A exata incidência e prevalência são difíceis de estabelecer, mas as lesões representam cerca de 5% a 7% dos tumores ósseos benignos. Nos ossos craniofaciais tem predileção pela maxila, podendo causar deformidade grave e assimetria, afetando igualmente ambos os sexos. Radiograficamente, pode apresentar diferentes padrões de imagem dependendo do grau de mineralização e maturação da lesão. .A avaliação da displasia fibrosa nas radiografias da região craniofacial pode ser difícil por causa das aparências variáveis e das estruturas que se sobrepõem, de modo que a tomografia computadorizada é um recurso relevante para o seu correto diagnóstico e planejamento de tratamento. O objetivo deste estudo foi caracterizar a displasia fibrosa através da análise da lacunaridade, um método multiescala para descrever padrões de dispersão espacial. Foram avaliados 10 pacientes (6 homens e 4 mulheres) comprometendo a maxila em sua grande maioria.

Para a análise da lacunaridade, empregou-se cortes tomográficos axiais e coronais e, posteriormente, selecionou-se as regiões de interesse das áreas displásicas e do osso normal contralateral por meio do software MATLAB®. Após testes e análises estatísticas, concluiu-se que os cortes coronais, com ampliação de 3x do seu tamanho original, mostraram superioridade em relação aos axiais e, que a lacunaridade foi menor nas áreas da região displásica em relação ao osso normal, ou seja, a primeira apresentou uma maior homogeneidade de textura que a segunda. Mediante isso, pela técnica da validação cruzada leave-one-out é possível separar os grupos com uma alta acurácia (94,75%) concluindo-se que a lacunaridade é um método de análise de imagens contributivo na caracterização da displasia fibrosa.

Fibrous dysplasia is an alteration of development characterized by replacing normal bone for dense connective tissue and immature trabecular bones, typically found in teenagers and young adults. Genetic modification which involves alpha-Gs protein appears to be the basis of the process. The exact incidence and prevalence are difficult to be established, but injuries represent about 5% to 7% of benign bone tumors. On the craniofacial bones, the tumors have a predilection for the maxilla and often can cause severe deformity and asymmetry affecting both sexes equally. Radiographically, it may have different patterns depending on the image degree of mineralization and maturation of the lesion. The evaluation of radiographs of fibrous dysplasia in the craniofacial region can be difficult because of the different appearances and structures that overlaps, however, CT is an important resource for proper diagnosis and treatment planning.

The aim of this study was to characterize the fibrous dysplasia by analyzing the lacunarity which is a multiscale method to describe patterns of spatial dispersion. We evaluated 10 patients (6 males and 4 females) and the maxillary was the most affected area. To the lacunarity analysis, we used an axial and coronal view and then were selected the regions of interest in the areas of dysplastic and contralateral normal bone by means of MATLAB® software. After tests and statistical analysis can be conclued that the coronal magnification 3x its original size showed superiority compared to thrust, and that the lacunarity was lower in the areas of dysplastic region in relation to normal bone, namely the first presented a more uniform texture than the second. Through this, the technique of cross-validation "leave-one-out" is possible to separate the groups with a high accuracy (94.75%) concluding that the lacunarity is a method of image analysis to characterize the contributory fibrous dysplasia.

Cemento-osseous dysplasia-like lesion and complex odontoma associated with an impacted third molar.

We present a case of a 36-year-old female with a benign fibro-osseous lesion consistent with cemento-osseous dysplasia (COD) that was located coronally to the crown of an impacted mandibular third molar tooth and was associated with a complex odontoma. The pathogenesis of this unusual association is discussed and the odontogenic origin of COD is suggested.

Queilite actínica: avaliação das alterações teciduais e graduação histológica em 458 casos / Actinic chelitis: evaluation of tissue changes and histological graduation in 458 case

A queilite actinica é uma lesão que acomete o vermelhão do lábio, principalmente o inferior, devido à exposição crônica e prolongada à radiação ultravioleta solar. Sabe-se'";que uma parcela dos casos de queilite actinica evoluirá para carcinoma epidermoide de lábio, mas quantos casos e quais, exatamente, ainda não é possível dizer. O prognósticoda queilite actinica, assim como a decisão terapêutica, são, atualmente, baseados em seu aspecto histopatológico mais importante: a displasia epitelial. O objetivo deste trabalhofoi avaliar as alterações citológicas e arquiteturais do epitélio de uma ampla amostra de casos de queilite actinica. Após essa etapa, os casos foram classificados segundo doissistemas de graduação: o proposto pela OMS e o binário. Depois dessa fase, foram selecionados casos de todas as graduações para serem submetidos, pela técnica deimuno-histoquímica, aos anticorpos anti-Ki 67 e anti-p53 mutada. Um total de 458 casos foram examinado. As alterações epiteliais mais frequentemente encontradas foi a perdade polaridade do estrato basal, o pleomorfismo nuclear e celular e o hipercromatismo. As graduações mais frequentes foram lesão de baixo risco e displasia epitelial moderada.Os resultados para as proteínas Ki 67 e p53 não mostraram relação estatisticamente significante com os graus histológicos. Que seja de nosso conhecimento, esta é a maior sériede queilites actínicas já analisada histologicamente e conclui-se que fatores como a determinação de quais as alterações teciduais devem ser consideradas, a representatividade do corteexaminado e a correspondência entre as alterações morfológicas e a instabilidade genética dos tecidos comprometem o uso prognóstico dos diferentes graus de displasia epitelial.

Actinic cheilitis is a lesion that affects the lip vermilion, due to chronic and prolonged exposure to solar ultraviolet radiation. It is known that a proportion of the actiniccheilitis cases wiIl evolve into squamous ceIl carcinoma of the lip, but how many cases and which ones wiIl suffer this process is not yet possible to say. The actinic cheilitisprognosis, as weIl as, the therapeutic decision are currendy based on epithelial dysplasia degree presented, which is considered the main histological characteristic. The aim ofthis study was to evaluate the epithelium architectural and cytological changes presented in a large sample of cases of actinic cheilitis. AfteIWards, the cases were classifiedfolIowing two grading systems: After this stage, cases were classified by two grading systems: the one proposed by WHO and the binary system. After, cases of allhistological grades were selected and submitted by means of immunohistochemistry, to the antibodies against Ki-67 and mutated p53. A total of 458 cases were exarnined andthe epithelial changes most frequendy found were the loss of polarity of basal ceIl; nuclear and celIular pleomorphism; and hyperchromatism. The grades most frequendyfound were low risk and moderate epithelial dysplasia. Results for p53 protein and Ki 67 showed no statistically significant relationship with the histological grades. To the best ofour knowledge, this is the largest series of actinic cheilitis histologically analyzed. It was concluded that factors such as determining which histological changes should beconsidered, the section representativeness, hence the correspondence between the morphological changes and genetic instability, compromise the prognostic use of epithelial dysplasia grading.