PCNA在角化囊肿及始基囊肿中的表达及意义

目的：探讨牙源性角化囊肿中PCNA的表达及意义。方法：采用免疫组化方法,检测PCNA在正常牙囊或残余牙板上皮及牙源性角化囊肿、始基囊肿中的表达。结果：PCNA在正常牙囊或残余牙板上皮中呈阴性表达,PCNA在角化囊肿及始基囊肿中呈阳性表达,表达率分别为35%和2.7%,统计学检验两者阳性表达率有显著性差异。结论：角化囊肿比始基囊肿可能更具有细胞增殖活性。     

牙源性囊肿抗增殖细胞核抗原抗体细胞动态分析

作者应用抗增殖细胞核抗原(PCNA)抗体免疫组织化学方法,研究囊肿壁内衬表皮细胞动态。以牙源性囊肿手术摘除的囊肿壁内衬表皮完整者作为标本。其中根端囊肿和含牙囊肿各20例,始基囊肿及牙源性角化囊肿25例,钙化性囊肿1例。造釉细胞瘤15例和正常牙龈5例作对照。 结果:囊肿内衬上皮及结缔组织的细胞核PCNA略呈阳性,尤其在囊肿衬里上皮的基底细胞及其上的2～3层细胞多见。根端囊肿表现在组织学上炎症反应     

牙源性角化囊肿细胞增殖抗原和表皮生长因子受体表达

目的　探讨牙源性角化囊肿衬里上皮细胞的增殖特点。方法　采用免疫组化染色方法 ,对牙源性角化囊肿、成釉细胞瘤、含牙囊肿、正常口腔粘膜上皮中细胞增殖抗原 Ki- 6 7和表皮生长因子受体 (EGFR)的表达进行分析比较。结果　牙源性角化囊肿中 Ki- 6 7表达较含牙囊肿高 ,与正常口腔上皮相似 ;复发的与未复发的牙源性角化囊肿 Ki- 6 7指数无显著性差异。牙源性角化囊肿中 EGFR表达呈阳性。结论　牙源性角化囊肿上皮增殖活跃 ,上皮增殖生长可能与表皮生长因子家族有关。     

下颌骨造釉细胞瘤肺转移报告及文献复习

造釉细胞瘤又称成釉细胞瘤,是较常见的颌骨良性肿瘤,属于临界瘤,具有明显的局部浸润、破坏颌骨和高复发率的特点。其发生有多种组织来源:可能来自于造釉器和牙板的残余上皮或牙周组织中的上皮残余;也可能来自于口腔粘膜上皮基底细胞;或来自于含牙囊肿和角化囊肿的衬里上皮[1]。     

开窗术治疗牙源性角化囊肿

Philipsen(1956年)提出将具有角化上皮的牙源性囊肿称为“牙源性角化囊肿”。1971年WHO简化囊肿的分类,将始基囊肿和角化囊肿归为一类,但不是所有的始基囊肿都是角化囊肿。牙源性角化囊肿占颌骨囊肿的3％～     

口腔颌面部肿瘤

成釉细胞瘤中MMP-2的表达及RNA干扰的抑制作用;口腔颌面部结节病14例临床分析;减压术治疗下颌骨大型牙源性角化囊肿的临床研究;唾液腺上皮性肿瘤1209例临床分析;成釉细胞瘤研究进展     

364例牙源性颌骨囊肿治疗与预后的探讨

本文报告牙源性囊肿３６４例，根尖囊肿，始基囊肿，含牙囊肿和角化囊肿分别占３９．６％，２２．８％，２８．８％和８．８％。全部病例行囊肿摘除骨腔刮治术。手术并发症主要为感染（占７７．１％）。囊肿复发率为５．５％，造釉细胞瘤变率为２．５％。本资料，始基囊肿和角化囊肿复发率／瘤变率近似，又明显高于含牙囊肿（Ｐ＜０．０５）。认为前两者组织学术源相同。提出根尖囊肿，含牙囊肿甚至始基囊肿囊肿区完好牙应予保留。除角化囊肿外，囊肿区保留牙与感染复发无明显关系。对术后感染，囊肿复发与瘤变防治问题作了讨论。     

牙源性囊肿及成釉细胞瘤细胞核DNA定量研究

目的　探讨角化囊肿、根尖囊肿、含牙囊肿和成釉细胞瘤上皮细胞的增殖特点。方法对角化囊肿、根尖囊肿、含牙囊肿上皮基底细胞和棘细胞及成釉细胞瘤外周柱状细胞和中央星网状细胞进行细胞核DNA含量测定 ,结合倍体和直方图分析。结果　牙源性角化囊肿及成釉细胞瘤细胞DNA增殖倍体含量较高 ,细胞增殖相对活跃。角化囊肿棘细胞增殖较基底细胞活跃。根尖囊肿DNA含量高与炎症刺激细胞增生有关 ,含牙囊肿细胞增殖不活跃。结论　细胞增殖活跃可能是牙源性角化囊肿及成釉细胞瘤具有局部侵袭性生长行为的生物学基础     

牙板在囊肿与肿瘤病因中的作用

一般认为牙源性囊肿与肿瘤来源于牙板剩余。作者通过对恒磨牙牙板发育过程的研究得出结论,认为牙板剩余不一定是角化囊肿与造釉细胞瘤的主要起源。作者对10只恒河猴胚和8只小猴(年龄自妊娠后60天至出生后24个月)的颌骨进行了组织学观察。最初,胚胎第67天,见到第一恒磨牙牙板自第二乳磨牙远中向后增生。胚胎第81天,第一恒磨牙帽状期开始,     

肿瘤抑制基因p53在牙源性肿瘤及囊肿中的表达及其意义

为了观察ｐ５３癌蛋白与牙源性肿瘤的关系，本文用免疫组织化学（经微波处理暴露抗原）方法观察了ｐ５３在牙源性肿瘤中的过表达。结果显示，在１６例成釉细胞瘤中有９例出现ｐ５３的表达，在１／２成釉细胞纤维瘤及１／１成釉细胞结维肉瘤中有过表达。阳性反应在不同类型的牙源性肿瘤中部位不同、阳性反应程度也不同。此外，对于牙源性囊肿的观察发现，３／６的牙源性角化囊肿、２／６的含牙囊肿的衬里上皮中发现ｐ５３的阳性表达、而６例根尖囊肿均为阴性。本研究结果显示，ｐ５３在牙源性肿瘤中、尤其是成釉细胞瘤中有较高的表达率，其阳性表达部位有助于认识不同的牙源性肿瘤和病变的来源、类型以及生物学行为。     

The Prevalence of EBV and KSHV in Odontogenic Lesions

ObjectivesOdontogenic lesions evolve as a result of altered dental development. This study aimed to evaluate the prevalence and the coinfection of Epstein-Barr virus (EBV) and Kaposi sarcoma–associated herpesvirus (KSHV) in radicular cysts, dentigerous cysts, odontogenic keratocysts, and ameloblastomas.MethodsPolymerase chain reaction (PCR) was used to analyse 66 cases of odontogenic lesions for the presence of EBV-DNA and KSHV-DNA. These lesions were 15 radicular cysts, 16 dentigerous cysts, 18 odontogenic keratocysts, and 17 ameloblastomas.ResultsEBV-DNA was detected in 24 (36.4%) of the studied samples as follows: 6 samples (40.0%) of radicular cysts, 4 (25.0%) of dentigerous cysts, 10 (55.6 %) of odontogenic keratocysts, and 4 (23.5%) of ameloblastomas (P = .168). KSHV-DNA was found in 16 (24.2%) of the studied samples as follows: 1 sample (6.7%) of radicular cysts, 6 (37.5%) of dentigerous cysts, 8 (44.4 %) of odontogenic keratocysts, and 1 (5.9%) of ameloblastomas (P = .001). Additionally, EBV and KSHV were positively correlated in all studied samples (P = .002).ConclusionsBoth EBV and KSHV are found in odontogenic cysts and ameloblastomas. KSHV and EBV are more prevalent in odontogenic keratocysts than in other studied odontogenic lesions. Further, there is a high prevalence of EBV and KSHV coinfection in odontogenic cysts and ameloblastomas.     

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.     

Metaplasia and degeneration in odontogenic cysts in man

Abstract. In a histologic study of the walls of 638 odontogenic cysts, the incidence of metaplastic and/or degenerative changes was recorded. There were 402 denial cysts, 81 dentigerous cysts, 15 lateral periodontal cysts, 1 gingival cyst and 139 odontogenic keratocysts.
Mucus cells were present in 39.6 % of the dental cysts, 42.0 % of the dentigeious cysts, 20.0 % of the lateral periodontal cysts and 3.7 % of the odontogenic keratocysts. There was no difference in incidence between the maxilla and mandible. The incidence of mucus cells increased with the age of the patient from whom the cyst was removed. Ciliated cells were present in 0.7 % of the dental cysts and 1.5 % of the odontogenic keratocysts, but were absent from dentigerous cysts and lateral periodontal cysts. Keratin was present in 2.0 % of the dental cysts, 2.5 % of the dentigerous cysts, and all of the odontogenic keratocysts, but was absent from lateral periodontal cysts. Hyaline bodies were present in 6.7 % of the dental cysts, 1.2 % of the dentigerous cysts, none of the lateral periodontal cysts and 9.4 % of the odontogenic keratocysts. Mineralized bodies were present in 2.5 % of the dental cysts, 7.4 % of the dentigerous cysts, 6.7 % of the lateral periodontal cysts and 12.9 % of the odontogenic keratocysts. The origin of these changes is discussed in the light of these findings.     

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.     

Discrimination of parakeratinised odontogenic keratocysts from other odontogenic and non-odontogenic cyst types by expression of a 38kd cell-surface glycoprotein

We have identified strong expression of a 38-kD cell surface glycoprotein (gp38), a marker of basal cell carcinomas (BCCs), in basal and suprabasal epithelial cell membranes of parakeratinised odontogenic keratocysts. In contrast, orthokeratinised cysts and most other odontogenic cyst types, ameloblastomas, normal stratified oral epithelium, cell rests of Malassez and glands of Serres, all proved negative. To our knowledge this is the first histochemical marker to distinguish between these major cyst types. It has obvious uses in the diagnosis of inflamed keratocysts and the separation of ameloblastomas from BCCs and may find a role in studies of the developmental biology of other odontogenic structures.     

Comparison of radiographic and MRI features of a root-diverging odontogenic myxoma,with discussion of the differential diagnosis of lesions likely to move roots

Lesions that can produce divergence of the roots of teeth in the mandible include odontogenic cysts (odontogenic keratocysts, lateral periodontal cysts and radicular cysts), ameloblastomas, odontogenic myxomas, central giant cell granulomas, adenomatoid odontogenic tumors and aneurismal bone cysts, and other tumors. Moreover most benign jaw lesions can do this occasionally. However, when lesions--which show interradicular tear-shaped radiolucencies--are small it is often difficult to interpret them radiographically, because they do not show characteristic radiographic features. We describe a comparison of radiographic and magnetic resonance (MR) features of a root-diverging odontogenic myxoma, with discussion of the differential diagnosis of lesions likely to move roots. In addition, we discuss radiographic and MR features of possible lesions, which show similar radiographic findings to odontogenic myxoma.     

An observational retrospective study of odontogenic cyst´s and tumours over an 18-year period in a Portuguese population according to the new WHO Head and Neck Tumour classification

Background Odontogenic cysts and tumours of the jaws represent one of the most prevalent groups of oral-maxillofacial lesions. We aimed to evaluate the clinical and pathological characteristics of a cohort of odontogenic cysts (OC) and odontogenic tumours (OT) of the jaws in a Portuguese population. Material and Methods This observational retrospective study analysed patients diagnosed with either an OC or OT of the jaws at a central hospital of Oporto, Portugal, between 1988 and 2006. Data collected from patients’ files included demographic, clinical, radiological and histopathological information. Recurrence was evaluated using univariate and multivariate analysis. Results The sample consisted of 397 patients, 231 males (58.2%) and 166 females (41.8%), with a mean-age of 36.7±17 years. Twenty-seven patients (6.8%) presented with more than one lesion providing a total of 433 lesions. There were 396 (91.5%) OC, mostly represented by radicular cysts (n=257;59.4%), dentigerous cysts (n=79;18.2%), or odontogenic keratocysts (n=50;11.5%). There were 37 (8.5%) OT, mostly represented by ameloblastomas (n=16;3.7%), and odontomas (n=9;2.1%). The most common initial clinical manifestation was swelling (n=224;51.7%). Recurrence was observed in 30 cases (6.9%), mostly in ameloblastomas (n=6;37.5%) and odontogenic keratocysts (n=12;24%). In the multivariate analysis the diagnosis classification of the lesion was the only independent and significant variable related with the recurrence (P=0.04). Conclusions Radicular cysts were the most commonly occurring type of OC and ameloblastomas the most commonly occurring OT. Amelobastomas and odontogenic keratocysts were the lesions with the highest rates of recurrence. This large sample provides useful information about the frequency profile and characteristics of OC and OT over a period of 18 years, allowing valuable comparison with data from other countries. Key words:Odontogenic cysts and tumours, radicular cyst, dentigerous cyst, odontogenic keratocyst, ameloblastoma, recurrence.