Rare presentation of adenomatoid odontogenic tumor in a pediatric patient: a case report

The adenomatoid odontogenic tumor (AOT) is a painless benign tumor with slow growth, usually asymptomatic. It has three variants: follicular, extrafollicular, and peripheral. In the follicular type, the tumor is associated with an impacted tooth, and maxillary canines are the most frequently affected. Association with primary teeth is very rare. Treatment consists essentially in a total lesion enucleation. The objective of this paper is to present the clinical case of a 7-year-old female patient with an adenomatoid odontogenic tumor associated with the crown of the left lower deciduous canine (73), dislodging it to the mandibular base and consequently shifting and also impacting the permanent lower canine (33). The lesion was treated with careful enucleation, preserving the permanent canine, which then had its eruption path released favoring its migration to an ideal position.     

Combined calcifying epithelial odontogenic tumor and adenomatoid odontogenic tumor

A case of combined epithelial odontogenic tumor associated with an unerupted maxillary canine tooth is described. The relative proportion of adenomatoid odontogenic tumor tissue and calcifying epithelial odontogenic tumor areas in a given tumor in determining the behaviour and growth potential of this entity is discussed.     

Adenomatoid odontogenic tumor: a report of an unusual maxillary lesion.

Adenomatoid odontogenic tumor is an odontogenic tumor that appears in the anterior portion of the jaws and more frequently, in the anterior maxilla usually in association with the crowns of inclused teeth. A case report of adenomatoid odontogenic tumor with an associated impacted right maxillary first premolar is presented. Under general anesthesia the lesion and the impacted tooth were removed. There was no recurrence at the 1 -year follow-up.     

PTCH mutations in sporadic and Gorlin-syndrome-related odontogenic keratocysts

Odontogenic keratocysts are relatively common lesions that may occur in isolation or in association with nevoid basal cell carcinoma syndrome (or Gorlin syndrome). The PTCH gene has been reported to be associated with Gorlin syndrome. We investigated 10 cases of non-syndromic keratocysts and two other cases associated with Gorlin syndrome, looking for PTCH mutations. Four novel and 1 known PTCH mutations were identified in five individual patients. Of the 5 mutations identified, 2 were germ-line mutations (2619C>A; 1338_1339insGCG) in 2 cysts associated with Gorlin syndrome, and 3 were somatic mutations (3124_3129dupGTGTGC; 1361_1364delGTCT; 3913G>T) in 3 non-syndromic cysts. This report describes PTCH mutations in both non-syndromic and Gorlin-syndrome-related odontogenic keratocysts in Chinese patients, and suggests that defects of PTCH are associated with the pathogenesis of syndromic as well as a subset of non-syndromic keratocysts.     

Maxillary odontogenic keratocyst with respiratory epithelium: a case report

We report a case of odontogenic keratocyst with a respiratory epithelial lining and a malformed impacted tooth in the maxilla of a 39-year-old Japanese female who suffered from swelling symptoms for half a year. CT examinations revealed an air-filled cystic lesion with an impacted tooth crown in the maxillary bone which expanded to the nasal cavity as well as to the maxillary sinus. Histopathologically, the surgically removed cyst wall consisted of fibrous granulation tissue with a lining of parakeratinized squamous epithelium as well as ciliated pseudostratified epithelium and with retention of desquamated keratin materials in the lumen. The impacted tooth was malformed lacking a root portion. We discuss the frequency of respiratory epithelium in odontogenic keratocysts.     

Investigation of chromosome 9q22.3-q31 DNA marker loss in odontogenic keratocysts

Multiple basal cell carcinomas and odontogenic keratocysts of the jaws are a feature of the inherited naevoid basal cell carcinoma syndrome (NBCCS), although both occur more commonly as single, sporadic cases. The NBCCS gene has been mapped to chromosome 9q22.3-q31 and loss of heterozygosity for DNA markers from this region has been observed in familial and sporadic basal cell carcinomas. Based on these observations, we undertook a pilot study to determine if a similar pattern of chromosome loss occurs in odontogenic keratocysts. DNA extracted from microdissected odontogenic keratocyst epithelium was examined for loss of heterozygosity for six polymorphic DNA markers mapping to human chromosome 9q22.3-q31. Allelotype loss was detected in epithelium from three, single, sporadic odontogenic keratocysts. These results implicate homozygous inactivation of the NBCCS gene in the initiation and progression of the odontogenic keratocyst.     

Adenomatoid odontogenic tumour: review of the literature and an analysis of 33 cases from South Africa

The adenomatoid odontogenic tumour (AOT) is a benign lesion of odontogenic origin. It is a slow growing tumour that results in a painless expansion of the jaws. This is a retrospective review of the demographic, clinical and radiographic features of AOTs diagnosed in a black South African population over 20 years. Of the 746 odontogenic tumours diagnosed, 4% were AOTs. The patients’ ages ranged from 9 to 37 years with a mean age of 15 years. The highest incidence was in the second decade of life (85%). The female to male ratio was 5.6:1. The maxilla was more commonly affected than the mandible in a ratio of 1.5:1. The sizes of the lesions ranged from 2 to 7 cm, with 60% involving an entire quadrant. All were of the central follicular type and appeared as well-demarcated radiolucent lesions. The canine was the most common impacted tooth. The treatment of choice was enucleation of the lesion, with no recurrences being reported.     

Podoplanin expression in human tooth germ tissues and cystic odontogenic lesions: an immunohistochemical study

J Oral Pathol Med (2010) 39 : 115–120
Background:  Podoplanin expression was described in mouse tooth germ and apical bud cells. The aim of this study was to analyse the podoplanin expression of human tooth germ tissues, adult teeth and odontogenic lesions immunohistochemically.
Study Design:  Nine human tooth germ biopsies and seven healthy permanent teeth extracted for orthodontic reasons were examined. Anti-podoplanin (D2-40) reactivity was investigated immunohistochemically. Five well-defined cystic odontogenic lesions (10 radicular cysts, 10 follicular cysts, three keratocystic odontogenic tumours, five ameloblastomas, and two adenomatoid odontogenic tumours) were analysed simultaneously.
Results:  Podoplanin expression was detected in the majority of epithelial and ecto-mesenchymal cells of human tooth germ tissues, odontoblasts and superficial dental pulp fibroblasts of permanent teeth. Cystic odontogenic lesions revealed positive reactions predominantly at the invasion front edge within basal epithelial layers.
Conclusion:  Podoplanin appears to be involved in the orthologic and pathologic processes of the formation of elongated cell extensions and odontoblastic fibers, in the epithelial–mesenchymal transition and local invasion during tooth germ development as well as in both reactive and neoplastic odontogenic cystic lesions.     

Calretinin expression in odontogenic cysts

Calretinin is a calcium-binding protein with a possible role as a calcium buffer, calcium-sensor, or regulator of apoptosis. Calretinin is expressed in neural tissue, is a specific marker of mesothelial cells, and has been demonstrated in the odontogenic epithelium during odontogenesis in rat molar tooth germs. Moreover, it has been found to be expressed in a high proportion of solid, unicystic, and multicystic ameloblastomas, whereas, on the contrary, no positive staining has been found in odontogenic keratocysts, residual cysts, and dentigerous cysts. The purpose of this study was to evaluate calretinin expression in radicular cysts, follicular cysts, orthokeratinized keratocysts, and parakeratinized keratocysts. A total of 70 odontogenic cysts, 24 radicular cysts, 24 follicular cysts, and 22 odontogenic keratocysts (10 orthokeratinized keratocysts, 12 parakeratinized keratocysts) were evaluated. All the radicular cysts, follicular cysts, and orthokeratinized keratocysts were negative. However in 8 of 12 parakeratinized keratocysts, there was a positivity to calretinin in the parabasal-intermediate layers of the cyst epithelium. This positivity to calretinin in the parabasal layers in parakeratinized keratocysts, similar to that found for other markers like PCNA and p53, could point to an abnormal control of the cell cycle and could help to explain the differences in the clinical and pathologic behavior of odontogenic keratocysts, in particular the differences found between orthokeratinized keratocysts and parakeratinized keratocysts.     

磷酸化p38促分裂原活化的蛋白激酶、尿激酶型纤溶酶原激活物及Ki-67在牙源性上皮性肿瘤中的表达

目的 检测磷酸化p38促分裂原活化的蛋白激酶(phosphorylated-p38 mitogen-activated protein kinase,p-p38MAPK)、尿激酶型纤溶酶原激活物(urokinase plasminogen activator,uPA)及Ki-67在牙源性上皮性肿瘤中的表达,探讨p-p38MAPK对牙源性上皮性肿瘤细胞增殖活性及侵袭性的影响.方法 根据2005年WHO关于牙源性肿瘤的分类标准,应用免疫组化方法检测p-p38MAPK、uPA和Ki-67在成釉细胞瘤(ameloblastoma,AB)、牙源性角化囊性瘤(keratocystic odontogenic tumour,KCOT)、牙源性钙化上皮瘤(calcifying epithelial odontogenic tumor,CEOT)、牙源性腺样瘤(adenomatoid odontogenic tumour,AOT)及牙源性钙化囊性瘤(calcifying cystic odontogenic tumour,CCOT)(以上为肿瘤组)和5例牙胚(对照组)中的表达.结果 p-p38MAPK在肿瘤组的阳性表达率为26%(17/65),在肿瘤细胞胞质和胞核均可见着色;uPA在肿瘤组的阳性表达率为78%(51/65),主要表现为肿瘤细胞胞质着色;Ki-67在肿瘤组的阳性表达率为95%(62/65),为弥散的肿瘤细胞胞核着色.p-p38MAPK、uPA和Ki-67在牙源性上皮性肿瘤的阳性表达率显著高于对照组(P＜0.05),三者的阳性表达呈正相关(P＜0.05).结论 p-p38MAPK信号传导通路可能以正性调节的方式调控uPA从而促进牙源性上皮性肿瘤的发生,可能是肿瘤发生、侵袭和增殖的重要途径之一.     

External tooth resorption associated with a peripheral odontogenic fibroma: review and case report

The purpose of the study is to document a rare case of a peripheral odontogenic fibroma with associated cervical and coronal tooth resorption in a 38 year old woman. Histopathological features are described, the clinical management outlined and follow‐up observations over 27 years detailed. The exophytic firm lesion, coral pink in appearance, located on the labial aspect of a maxillary right lateral incisor was excised, fixed in formalin and prepared for histological evaluation. The resorption cavity and adjacent soft tissue were treated by the topical application of trichloroacetic acid prior to restoration with a glass‐ionomer cement and subsequent root canal treatment. Histologically, the body of the lesion was characterized by the presence of odontogenic epithelium embedded in a mature fibrous stroma. Areas of dystrophic calcification could also be identified. The features were consistent with a diagnosis of a peripheral odontogenic fibroma. The clinical result of treatment assessed 27 years postoperatively showed no evidence of recurrence of the peripheral odontogenic fibroma. External cervical and coronal tooth resorption can, on rare occasions, prove to be a clinical feature associated with peripheral odontogenic fibroma. Treatment of the tumour mass and the resorptive lesion can provide a successful outcome.     

Two adenomatoid odontogenic tumours of the maxilla: A case report

An adenomatoid odontogenic tumour (AOT) is a well-recognised benign tumour that enlarges slowly. We report here the rare occurrence of two separate tumours in the anterior maxillary region that have not been documented previously. They were associated with unusual findings such as relatively large size, a supernumerary tooth, rapid growth with cortical perforation, and multilocular appearance with root resorption on plain radiograph.     

PTCH1 and SMO gene alterations in keratocystic odontogenic tumors

Keratocystic odontogenic tumors (KCOTs, previously known as odontogenic keratocysts) are aggressive jaw lesions that may occur in isolation or in association with nevoid basal cell carcinoma syndrome (NBCCS). Mutations in the PTCH1 (PTCH) gene are responsible for NBCCS and are related in tumors associated with this syndrome. Mutations in the SMO gene have been identified in basal cell carcinoma and in medulloblastoma, both of which are features of NBCCS. To clarify the role of PTCH1 and SMO in KCOTs, we undertook mutational analysis of PTCH1 and SMO in 20 sporadic and 10 NBCCS-associated KCOTs, and for SMO, 20 additional cases of KCOTs with known PTCH1 status were also included. Eleven novel (1 of which occurred twice) and 5 known PTCH1 mutations were identified. However, no pathogenic mutation was detected in SMO. Our findings suggest that mutations are rare in SMO, but frequent in PTCH1 in sporadic and NBCCS-associated KCOTs. Abbreviations: NBCCS, nevoid basal cell carcinoma syndrome; KCOTs, keratocystic odontogenic tumors; BCCs, basal cell carcinomas.     

Calcifying epithelial odontogenic tumour presenting at a surgical site: case report

We describe the management of a calcifying epithelial odontogenic tumour with an atypical clinical presentation at the site of a previously surgically exposed impacted maxillary canine in a 51-year-old woman.     

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牙源性囊肿是一组常见于颌骨内的良性病变,一般可根据临床体征和影像学发现作出初步诊断。颌骨牙源性囊肿的手术治疗方法应根据囊肿类型、患者年龄、病变大小及罹患部位等决定。青少年含牙囊肿,预期囊内含牙可自行萌出者,可采用袋形术。病变范围较小的颌骨牙源性囊肿,刮除术为最好的治疗方法。若根尖周囊肿的病源牙可保留,术前应完成根管治疗。术中辅以Carnoy液处理囊壁可减少角化囊肿术后复发。破坏范围大的颌骨牙源性囊肿可选择第一期袋形术,第二期刮除术,有利于减少邻近结构的损伤。颌骨切除术较少应用于治疗颌骨囊肿,主要适应证是病变破坏范围大,多次复发的牙源性角化囊肿。     

Blood group antigens A and B in ameloblastomas, odontogenic keratocysts and non-keratinizing cysts

abstract — The expression of blood group antigens A and B has been studied in 8 ameloblastomas, 16 odontogenic keratocysts from patients with basal cell nevus syndrome, 11 odontogenic keratocysts from patients without the syndrome, and 12 non-keratinizing odontogenic cysts, using a double layer immunofluorescence staining technique. The amount of antigen in the lesions was compared with the content of antigen in normal buccal mucosa from each patient. All ameloblastomas reacted negatively, three cysts from the patients with the basal cell nevus syndrome reacted negatively, and the odontogenic keratocysts from patients without the syndrome as well as the non-keratinizing odontogenic cysts all gave a positive reaction.     

36例与阻生牙相关的牙源性角化囊肿的临床影像学特点分析

目的:分析与阻生牙有关的牙源性角化囊肿的临床和影像学特点。方法:对235例牙源性角化囊肿中36例与阻生牙有关的临床、影像学资料进行回顾分析。结果:在与阻生牙有关的牙源性角化囊肿病例中,男女比例为1.77∶1,下颌磨牙-下颌支部26例,占72.22%;19例（52.8%）在20~30岁就诊。单房型27例（75%）,多房型9例（25%）;牙冠位于囊内13例（36.11%）,整个牙位于病变内15例（41.67%),而阻生牙位于病变一侧8例（22.22%）。结论:与阻生牙有关的牙源性角化囊肿的一个主要影像学特点是,整个牙被病变包绕或位于囊肿一侧,而表现为冠周密度减低影像者较少。     

Expression of cell cycle and apoptosis-related proteins in sporadic odontogenic keratocysts and odontogenic keratocysts associated with the nevoid basal cell carcinoma syndrome.

Odontogenic keratocysts are occasionally (4-5%) associated with the nevoid basal cell carcinoma syndrome, a pleiotropic, autosomal disorder presenting a spectrum of developmental abnormalities and a predisposition for the development of different neoplasms. The aim of this study was to establish whether keratocysts showing clinically aggressive behavior associated with nevoid basal cell carcinoma syndrome reflect differences in cellular proliferation rate and/or in the expression of oncoproteins and tumor suppressor genes. For this reason, formalin-fixed paraffin-embedded sections of odontogenic keratocysts associated with the nevoid basal cell carcinoma syndrome (16 cases) and sporadic odontogenic keratocysts (16 cases) were compared for expression of proliferating cell nuclear antigen (PCNA) and p53, bcl-2, and bcl-1 (cyclin D1) onco-proteins. Most of the epithelial lining of odontogenic keratocysts associated with the nevoid basal cell carcinoma syndrome showed nuclear immunopositivity for p53 protein and overexpression of cyclin D1 with various degrees of staining intensity. All sporadic odontogenic keratocysts were negative for p53 and cyclin D1. The expressions of bcl-2 oncoprotein were found to be substantially similar between the two groups of lesions, with a cytoplasmic immunopositivity localized only in the resting reserve basal layer of the epithelium. PCNA expression showed no statistically significant difference between the two groups of lesions. In conclusion, the finding of cyclin D1 and p53 overexpression in odontogenic keratocysts associated with the nevoid basal cell carcinoma syndrome could be considered a hallmark of a mutated cellular phenotype, thus leading to the hypothesis that their aggressive clinical behavior could be due to a dysregulation of the expression of cyclin D1 and p53 proteins, involved in a check-point control of cellular proliferation.     

An adenomatoid odontogenic tumor with unusual clinical features

Adenomatoid odontogenic tumors are uncommon odontogenic lesions characterized by duct-like structures that form from the epithelial component of the lesion. Most of these masses develop in the second or third decade of life, and there is a strong female bias in occurrence. Typically, these lesions arise in the lateral incisor/canine region of the maxilla, where they produce a swelling. Only in very rare cases is the lesion found distal to the premolar area. Nearly all of these growths are associated with an embedded anterior maxillary tooth (usually a canine), and most resemble a 1-3 cm diameter dentigerous cyst. Radiopacity is reported in two-thirds of cases. This article describes the case of a 9-year-old Caucasian male who presented with a painless swelling in the left premolar-molar region of his maxilla. This case is of particular interest because the features (patient age, gender, lesion location, size, and radiographic findings) were not typical of adenomatoid odontogenic tumor.