bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrastructure of altered rat enamel beneath fluoride‐induced cysts
Authors: Simmelink J. W. , Lange A.
Published: April 2006

The effect of a single injection of sodium fluoride (60 mg/kg) on the development of rat molar enamel beneath fluoride‐induced sub ameloblastic cysts was studied by transmission electron microscopy using un decalcified sections. Three bands of altered enamel were identified and defined as the cyst surface band, the hypo plastic band, and the hyper calcified band. The irregular cyst surface band, not previously described, was found to have two components: electron‐dense enamel globules and organic spherules. The electron‐dense globules consisted of small, randomly arranged crystals (confirmed by selected area electron diffraction) occurring within a stippled organic matrix. The organic spherules have staining properties similar to stippled material and lack a crystalline component. They may be a form of organic material being extruded from the underlying developing enamel. The critical role of normal matrix production and ameloblast Tomes’ process Structure on the development of the crystal orientation and rod pattern is discussed.
Expression of Class I and Class II major histocompatibility complex antigens on epithelial cells in recurrent aphthous stomatitis
Authors: Savage N. W. , Seymour G. J. , Kruger B. J.
Published: April 2006

Abstract The concept of an immunopathogenesis in the establishment and progression of the recurrent aphthous stomatitis (RAS) lesion is well accepted. In this study the expression of Class I and Class II major histocompatibility complex (MHC) antigens on the epithelial cells in the preulcerative, ulcerative and healing phases of RAS lesions was investigated using monoclonal antibodies in an immunohistological technique. Both Class I and Class II MHC antigens were found on the basal cells in preulcerative lesions. As the lesions progressed to the ulcerative phase, antigen expression occurred on the cell membranes throughout the entire thickness of the epithelium. With healing, the expression of both Class I and Class II MHC antigens on epithelial cells declined to a stage where there was little or no detectable antigen on the cell membranes. Although cytotoxity of epithelial cells in RAS lesions is accepted the role of MHC antigen expression on these cells is uncertain and remains to be ascertained. Nevertheless, the results of the present study indicate that MHC antigens are expressed by epithelial cells in RAS and their expression follows a defined sequence.
Angular cheilitis: a clinical and microbial study
Authors: Öhman S. Christer , Dahlen G. , Moller A. , Öhman A.
Published: April 2006

Abstract The purpose of this prospective study was to re‐examine the relative importance of various factors in the pathogenesis of angular cheilitis. Sixty‐four patients with cheilitis were examined clinically and microbiologically. In addition, a subsample of 23 patients was examined for serum iron and transferrin. The clinical appearance of the lip lesions fell into 4 categories. A ground rhagad at the corner of the mouth involving adjacent skin, was the most frequent type among dentate patients, whereas among denture wearers a deep lesion following (he labial marginal sulcus was frequently observed. Dentate patients and denture wearers with cheilitis often had atopic constitution or cutaneous diseases. Pathogenic microorganisms were cultured from the lesions in all 64 patients; Staphylococcus aureus in 40 patients and Candida albicans in 45. The results of this study indicate a correlation between angular cheilitis and pathogenic microorganisms. Furthermore, among dentate patients, a correlation exists between cutaneous discomfort and angular cheilitis. Other etiological factors suggested for this disorder were found to be of subordinate importance.
Indirect immunofluorescence of oral lichen planus
Authors: Camisa C. , Allen C. M. , Bowen B. , Olsen R. G.
Published: April 2006

Abstract Sections of lesional tissue from 6 patients who exhibited only oral lesions of lichen planus (LP) were incubated with autologous serum and studied immunopathologically for the presence of lichen planus specific antigen (LPSA). None of the specimens was positive for LPSA. Serum from the oral LP patients was subsequently incubated with allogeneic cutaneous LP lesional tissue sections, which resulted in the demonstration of LPSA in 2 of the 4 sera examined. These results suggest an immunologic relationship between cutaneous LP and at least some cases of oral LP.
The identification of myoepithelial cells in human salivary glands. A review and comparison of light microscopical methods
Authors: Palmer R. M.
Published: April 2006

Abstract Myoepithelial cells have frequently been implicated in salivary gland tumour histogenesis. A major problem has been the reliable identification of these cells at the light microscopical level, both in tumours and in normal salivary glands. Many methods have been advocated, often with comparatively little evaluation in normal human tissue and with limited comparison between techniques. This paper reviews the application of histological staining techniques, enzyme histochemistry and immunocytochemistry with antibodies to actin, myosin and keratins. The only reliable method was immunocytochemistry with an antibody to smooth muscle myosin, with immunofluorescence on frozen tissue and immunoenzyme labelling on methacarn‐fixed/paraffin‐processed material. Formalin fixation did not permit successful staining. Monoclonal antibodies to specific keratin polypeptides may prove to be a useful label of myoepithelial cells but at the present time the available cytokeratin antibodies preferentially stain duct cell populations.
Malignant fibrous histiocytoma of the tongue: report of a case and ultrastructural observations
Authors: McMillan M. D. , Smillie A. C. , Ferguson J. W.
Published: April 2006

A 42‐year‐old female presented with a 2.5 cm symptomless swelling on the left lateral surface of the tongue. Histologically, there were large, often pleomorphic, fibroblast‐like and histiocyte‐like cells, multinucleate giant cells and cells of variable morphology. Many of the cells had abundant vesicular cytoplasm. There were also aggregations of neutrophilic or eosinophilic leukocytes, or both. The cells in some areas formed a fascicular or storiform pattern, or both. Ultrastructurally, the vesicular appearance was due mostly to markedly dilated endoplasmic reticulum, but many of the neoplastic cells contained some lipid. There were some myofibroblasts and a few xanthofibroblasts. The cells of variable morphology had many of the ultrastructural features of the fibroblast and histiocyte‐like cells. There were also some small undifferentiated cells with minimal cytoplasm. These ultrastructural features confirmed the histological diagnosis of malignant fibrous histiocytoma.
The effect of iron deficiency on early oral carcinogenesis in the rat
Authors: Prime S.S. , MacDonald D. G. , Sawyer D. R. , Rennie J.
Published: April 2006

In order to further investigate the known influence of iron deficiency on 4NQO oral carcinogenesis in the rat, groups of iron‐deficient and iron‐sufficient Charles River white rats were painted with carcinogen for 8 weeks or 14 weeks and then left untreated for 32 weeks or 26 weeks respectively. Tumour development and epithelial dysplasia were assessed at the time of killing. Animals painted for 14 weeks showed more severe dysplasia than those painted for 8 weeks, but no significant differences were noted between corresponding iron‐deficient and iron‐sufficient groups.
A semi‐quantitative assessment of the histopathology of oral lichen planus
Authors: Hedberg N. , Ng A. , Hunter N.
Published: April 2006

In a retrospecitve study of 112 cases, an attempt has been made to further delineate the histopathological parameters which are useful in making a diagnosis of oral lichen planus. The results of this study show that mononuclear infiltration beneath and adjacent to the epithelium, parakeratosis and degeneration of the basal layer of the epithelium were consistent features. Linear regression analyses of the parameters studied provided partial support for a cell‐mediated immune mechanism.
Mast cells in oral lichen planus
Authors: Jontell M. , Hansson H‐A. , Nygren H.
Published: April 2006

Biopsies from lichen planus affected oral mucosa were compared with biopsies from healthy oral mucosa, in terms of the number of mast cells, their location and their morphological alteration at the light microscopic and electron microscopic level. In comparison with the normal oral mucosa an increased number of mast cells was found below the subepithelial infiltrate. This difference was statistically highly significant (p < 0.001). In the deeper part of the infiltrate mast cells were found to contain granules which presented an altered morphology upon electron microscopic examination. These cells had many of the ultrastructural changes that have been reported for mast cells undergoing degranulation. The present morphological observations suggest that mast cells participate in the recruitment of lymphocytes to the subepithelial infiltrate.
Intracytoplasmic crystalloids in granular cell ameloblastoma
Authors: Takeda Y.
Published: April 2006

A case of granular cell ameloblastoma with numerous intracytoplasmic crystalloids is reported. The intracytoplasmic crystalloids are linear in shape and up to 15 μm in length, and stained similar to the intracytoplasmic granules of granular cell ameloblostomas which have been identified histochemically as lysosomes. The intracytoplasmic crystalloids in the granular cell ameloblastoma presented here probably reflect a variant type of lysosome, possibly due to cellular degeneration.
Enlargement of rat submandibular salivary gland induced by single amputation of lower incisor teeth
Authors: Takeda Y. , Hirose H. , Enomoto S.
Published: April 2006

Histological, histometric and ultrastructural studies of rat submandibular salivary glands (SMG) following single amputation of lower incisor teeth were made. The SMG enlargement occurred after the tooth amputation, and its maximal increase of weight was reached 7 days later. The results of histological and histometric observations showed that the enlargement of SMG was due to both hypertrophy and hyperplasia of the acinar cells, and hypertrophic acinar cells were ultrastructurally characterized by well‐developed organelles such as rough‐surfaced endoplasmic reticulum and Golgi apparatus which filled the entire cytoplasm. Hydropically swollen nerve endings with disappearance of vesicles were frequently found. In later stages, degenerative or necrotic cells were scattered in the acini, and the size and the structure of the remaining acinar cells became gradually similar to those of non‐treated glands. The morphological changes seen in the enlarged SMG induced by single amputation of the lower incisor teeth in rat were similar in many ways to those of sialadenosis induced experimentally by active sympathomimetic drugs.
The dentinogenic ghost cell tumor
Authors: Tajima Y. , Ohno J. , Utsumi N.
Published: April 2006

An unusual case of dentinogenic ghost cell tumor, a peculiar variant of calcifying odontogenic cyst, is reported. The tumor consisted predominantly of ghost cells with occasional areas of “dentinoid” in close proximity to masses of ghost cells. The presence of ameloblastoma‐like nests of epithelium was characteristic of the present case were interpreted as a degenerative phenomenon exhibiting an inductive effect with formation of abundant ghost cells, occurring within a pre‐existing ameloblastoma. The term of “dentinogenic ghost cell tumor” is employed for this unique lesion presented in this report. The literature describing the neoplastic potential of the calcifying odontogenic cyst is briefly reviewed.
Pulpal responses to amalgam restorations in cavities with and without smear layer removal
Authors: Jodaikin A. , Austin J.C. , Cleaton‐Jones P. E.
Published: April 2006

A conventional low copper amalgam was placed in cavities with and without smear layer removol and the amlagam restorations were covered with a resin overlay. The restored teeth were retrieved at 2, 28 and 56 days postoperatively in order to test for leakage and then pulpal reactions. More inflammation was seen in the teeth from which the smear layer had been removed. Abscesses were present in 6 teeth at 28 days but only one was associated with demonstrable bacteria. This study does not support smear layer removal before insertion of low copper amalgam restorations.
HLA‐DR antigen detection in giant cell lesions
Authors: Regezi J. A. , Zarbo R. J. , Lloyd R. V.
Published: April 2006

Sixty‐six giant cell lesions ranging from inflammatory to neoplastic were evaluated for HLA‐DR antigens using formalin/paraffin tissue and a monoclonal antibody labelled by the avidin‐biotin peroxidase. HLA‐DR antigens were expressed in nearly all lesions, predominantly on round, macrophage‐like cells. Granulomatous inflammatory lesions were generally more immunoreactive than non‐inflammatory lesions. Multinucleate giant cells were relatively unreactive in non‐inflammatory lesions as compared to inflammatory lesions. Determination of HLA‐DR expression does not appear to be helpful in discriminating between the various giant cell lesions.
Product identification of ameloblastomas: an immunohistochemical study
Authors: Nadimi H. , Toto P. D.
Published: April 2006

Twenty‐nine solid, plexiform and follicular ameloblastomas and control human developing teeth al different stages of maturation were formalin‐fixed, paraffin‐embedded and sectioned for the study of laminin, fibronectin, and mannosyl, glucosyl, and galactosyl residues using the peroxidase antiperoxidase (PAP) and avidin‐biotin peroxidase complex (ABC) staining methods, respectively. Monospecific antibodies to laminin and fibronectin and the affinity of the lectins for mannosyl, glucosyl, and galactosyl residues with RCA‐I. Laminin is present during the stage of morphodifferentiation of normal tooth development within the basement membrane. Following cytodifferentiation and calcified matrix deposition, laminin is not detectable. Laminin is also found in the basement membrane of both follicular and plexiform ameloblastomas. In contrast, fibronectin is reactive only up to the stage of morphodifferentiation among the mesenchymal cells and at the epithelial‐mesenchymal interface, and it becomes unreactive upon differentiation of odontoblasts and mesenchymal pulp tissue as well. Unlike laminin, fibronectin is unreactive in the basement membrane of plexiform follicular and ameloblastomas.
Histological distribution of phosphophoryn in normal and pathological human dentins
Authors: Takagi Y. , Sasaki S.
Published: April 2006

Dentin phosphophoryn is a highly phosphorylated protein which has a hydrophilic character but is not soluble in dilute acetic acid. A histochemical method was developed for staining this protein with Stains‐all® in situ utilizing those chemical properties. We have succeeded in detecting the presence of this protein in circumpulpal orthodentin of human permanent and deciduous teeth, but not in mantle dentin, secondary dentin and reparative dentin. Phosphophoryn staining was also absent in the dentin of dentinogenesis imperfecta (DI) Type II, a genetic disorder of dentin formation. From these results, it is suggested that phosphophoryn is synthesized and secreted only by physiologically‐differentiated odontoblasts and that the mineralization processes of mantle, secondary, reparative and DI dentins may be different from that of circumpulpal orthodentin.
Pigmentary changes in rat oral mucosa following antimalarial therapy
Authors: Savage N. W. , Barber M. T. , Adkins K. F.
Published: April 2006

Pharmacogenic pigmentation of the oral mucosa has been reported following the use of a number of anti‐malarial drugs. The nature and distribution of the pigment is inconclusive in the literature. The aim of the present study was to document pigment deposition within the oral mucosa of DA rats following prolonged chloroquine and pyrimethamine administration. The drugs were given as a combined dosage and separately to different groups via stomach gavage tube. After 12 weekly administrations the palatal mucosa was examined histochemically and ultrastructurally for changes in numbers and size of active melanocytes using the dopa‐oxidase technique. The serum was analysed for changes in ACTH and testosterone levels. Morphometric analysis of cells incubated for dopaoxidase showed a significant increase in the size of dopa positive cells with both drugs but an increase in the number of active melanocytes with chloroquine only. Serum levels of ACTH remained unchanged with both drugs but pyrimethaminc caused an elevation in testosterone.
Human papillomavirus Type 2 DNA in oral verrucous carcinoma
Authors: Adler‐Storthz K. , Newland J. R. , Tessin B. A. , Yeudall W. A. , Shillitoe E. J.
Published: April 2006

Tissues from patients with oral verrucous carcinoma were examined for the presence of human papillomavirus (HPV). The tissues were stained for the presence of the type common papillomavirus antigen by immunohistochemical staining and the presence of HPV DNA was determined by in situ hybridization with biotin‐labelled HPV DNA probes. Seventeen tissue specimens were obtained from 9 patients, and included pre‐malignant lesions and primary and recurrent tumors. One pre‐malignant lesion was positive for papillomavirus structural antigen. This lesion and lesions from 2 other patients hybridized at low stringency (Tm‐35°) to 3 different HPV probes. By hybridization under high stringency conditions (Tm‐20°), the virus in each case was identified as being HPV2.
Effect of diphosphonate on the prevention of X‐radiation‐induced inhibition of bone formation in rats
Authors: Ubios A. M. , Guglielmotti M. B. , Cabrini R. L.
Published: April 2006

A histologic and histometric study of the effect of EHDP (ethane‐ 1–hydroxy‐1,1–diphosphonate) on the alveolar wound healing of irradiated animals is presented. This drug was selected based on its osteosclerotic effect when applied at low doses. The three left mandibular molars of 80 male Wistar rats were extracted. The rats were grouped into 4 sets of 20 rats each. Group I received no further treatment; Group II received daily intraperitoneal injections of EHDP (7.5 mg/Kg of body weight during 10 days); Group III: 15 Gy of X‐radiation were applied to the head; and Group IV were irradiated and injected with EHDP as were animals of Groups III and II. Half of the animals were killed after 14 days and the other half 30 days post‐extraction. Sections were made at the level of the mesial socket of the first molar in a buccolingual orientation, on which histometric determinations of bone activity were made. The results showed the attenuation of the inhibitory effect of radiation on bone formation when the animals were treated with EHDP.
A histochemical study of APUD ability in the taste buds of experimentally induced zinc‐deficient mice
Authors: Kondo I. , Watanabe Y. , Ito Y. , Hisada T.
Published: April 2006

To explore the relationship between taste acuity and zinc deficiency, a histochemical investigation was made into the taste buds of mice fed a zinc‐deficient diet. Nine weeks after the start of the diet, the average serum zinc level of the mice was 45% lower than that of a control group of mice. Moreover, growth was arrested significantly. Two‐bottle preference tests revealed that the intake ratio of 10‐5M quinine hydrochloride solutions had increased markedly in the zinc‐deficient mice compared with the controls. The circumvallate taste buds showed no morphological changes. Fluorescent histochemical examination showed an uptake of a monoamine precursor (5‐HTP) by the gustatory cells in the zinc‐deficient mice after the 5‐HTP treatment. Upon immunohistological examination, however, no serotonin immunoreactivity appeared in the gustatory cells of the zinc‐deficient mice after the 5‐HTP treatment. These results suggest that zinc‐deficiency may induce hypogeusia and decrease the ability to transform a monoamine precursor to monoamine in the gustatory cells, albeit the monoamine precursor uptake ability is not affected.
Evaluation of pH changes in inflammation of the subcutaneous air pouch lining in the rat, induced by carrageenan, dextran and staphylococcus aureus
Authors: Punnia‐Moorthy A.
Published: April 2006

The lowering of tissue pH in inflammation is generally accepted as the important mechanism for the failure of local anaesthesia in inflamed tissues. However, studies relating to pH changes in inflammation are scant in the literature and more importantly the findings are inconsistent. The purpose of this study is therefore to re‐evaluate the pH changes using more reliable models of inflammation and pH measurement techniques. Wistar rats were used in the study. The inflammatory model used was based on the air pouch granuloma technique. Carrageenan, dextran and staphylococcus aureus were used as irritants and the pH measurements were made with a miniaturised glass tissue pH electrode designed by Roche. Results showed only a small lowering of pH in inflammation, of the order of about 0.5 pH unit. It may be possible that even such a small pH reduction would affect the buffer capacity of the tissues rendering the local anaesthetics less effective, but this needs to be confirmed with further studies.
Intraoral Masson's vegetant intravascular hemangioendothelioma
Authors: Bowman J. M. , Levy B. A. , Sauk J. J. , Weinstein M. D.
Published: April 2006

Two cases of Masson's vegetant intravascular hemangioendothelioma are described. The intraoral appearance of these reported lesions are rare. Due to histologic similarities to angiosarcoma and the benign progression of vegetant intravascular hemangioendothelioma, a thorough discussion of these diseases is presented.
The implications of inflammation in odontogenic keratocysts
Authors: Rodu B. , Tate A. L. , Martinez M. G.
Published: April 2006

The histologic features of 112 odontogenic keratocysts (OKC's) were examined from both a clinical and histopathological perspective with emphasis on the microscopic presence of inflammation and its relationship to transformation of the classic epithelial cyst lining found in OKC's to a nonkeratinized lining characteristic of common inflammatory odontogenic cysts. Eighty‐five (76%) of these cases exhibited inflammation. The sensitivity of inflammation as a predictor of this aforementioned transformation is 100%, and its positive predictive value is 88%. The specificity of the same parameters remains high at 73%. Using previous studies, the implications of these findings on the biologic behavior of OKC's is discussed with special reference to therapeutic considerations.
Experimental extra‐follicular histogenesis of follicular cysts
Authors: Altini M. , Cohen M.
Published: April 2006

An animal model has been developed in which implantation cysts have been produced very close to developing teeth within the jaws of Vervet monkeys. Various deciduous teeth were extracted from both the maxilla and the mandible of 6 young Vervel monkeys. After 4 weeks, full thickness mucoperiosteal flaps were raised in these areas, up to 6 recipient sites were prepared in each monkey by drilling holes in the alveolar bone and small pieces of autogenous palatal mucosa were placed in these graft recipient sites. One monkey was killed after 5, 8, 22 and 25 weeks respectively and 2 after 52 weeks. Of the 33 implants placed, cyst formation occurred from 11 (33%). The distribution of the cysts was irregular in that 4 cysts were produced in each of 2 animals while no cysts were found in another 2 animals. The cysts produced were filled with keratin and lined partly by a thick keratinising epithelium and partly by a thin non‐keratinising epithelium only a few cell layers thick. In one of the animals killed after 52 weeks, (he follicle of an erupting premolar tooth had collided with one of the cysts resulting in the cyst lining becoming incorporated into the follicle, partly replacing the follicular reduced enamel epithelium and forming now an integral part of the follicle. This observation supports the hypothesis that the follicular odontogenic keratocyst has an extra‐follicular origin arising alter the eruption of a tooth into a pre‐existing cyst cavity.
Ultrastructure of oral leukoplakia and lichen planus. II. A correlated scanning and transmission electron microscopic study of epithelial surface cells
Authors: Jungell P. , Malmström M. , Wartiovaara J. , Konttinen Y.
Published: April 2006

Nine cases of homogenous leukoplakia and 21 cases of lichen planus (11 reticular and 10 erosive) were studied under the scanning and transmission electron microscopes. Characteristic differences between leukoplakia and lichen planus in surface patterns of the epithelial surface cells were noted. Microridges in leukoplakia form parallel and anastomosing rows whereas the picture in lichen planus is irregular with microridges varying in width. The transmission electron microscopic findings confirm and correlate with these findings, the microridges representing invaginations of the plasma membrane. The keratin patterns exhibited by the surface cells were also characteristic regarding type and site of lesion. Scanning electron microscopy can be used as an additional diagnostic aid in differentiating these lesions.
Intravascular fasciitis: a case report of an intraoral location
Authors: Kahn M. A. , Weathers D. R. , Johnson D. M.
Published: April 2006

Nodular fasciitis is a benign reactive fibroblastic proliferation which usually arises from the superficial or deep fascia of the extremities and trunk. In 1981 a distinct variant, intravascular fasciitis (IVF), was reported which possessed the same clinical and histological features of more ordinary forms of nodular fasciitis but, in addition, had a striking involvement of associated arteries and/or veins. A case of intraoral IVF is presented and its clinical and histologic features are compared with those of IVF found elsewhere in the body. A brief discussion of etiology and differential diagnostic considerations is also included.
Pathological characteristics metastatic carcinoma in the human mandible
Authors: Hashimoto N. , Kurihara K. , Yamasaki H. , Ohba S. , Sakai H. , Yoshida S.
Published: April 2006

Based on the large celloidin‐embedded section method, human mandibles from 62 autopsied carcinoma cases were examined histologically to determine the pathological characteristics of any mandibular metaslases. Metastasis was confirmed histologically in 10 (16%) of the 62 cases and was comparatively frequent with gastric and pulmonary carcinomas. The hemopoietic areas in the mandibular marrow seemed to favor the early deposition of tumor cells. These micrometastatic foci seemed to increase in size, spreading to all parts, including the periodontal tissue or anterior part of the mandibular body. Increased hemopoietic activity following lodgement, seemed to play an important role for further metastases. Roentogenographic examination did not seem to be the best method of detecting metastasis.
The calcifying potential of the pulpless open apex in untreated teeth of dogs
Authors: Tziafas D. , Beltes P. , Molyvdas I.
Published: April 2006

Pulpectomies were performed on 22 immature premolars (44 root canals) from 3 young dogs. The root canals remained unfilled and the access cavities were sealed with amalgam. After observation periods of 7, 15 and 45 days, the apical and periapical regions of the teeth were evaluated histopathologically. Hard tissue formation was found in 32 open apices. The apical calcification occurred only in specimens with intracanal vital tissue. The severity of periapical inflammatory response had no relationship to the presence or absence of apical hard tissue formation. No apical bridging was seen in specimens where epithelial proliferation had occured.
Effect of the application of a mucin‐based saliva substitute on the oral microflora of xerostomic patients
Authors: Weerkamp A. H. , Wagner K. , Vissink A. , 's‐Gravenmade E. J.
Published: April 2006

A cross‐sectional study among 46 xerostomic patients was carried out to determine the influence of a mucin‐based artificial saliva on the microflora of standardized oral washings. Patient and non‐xerostomic control groups were formed according to the use of saliva substitute (ad libitum or from an intraoral reservoir) and dentition (dentate, edentulous, full dentures). Only few differences were observed among the subgroups based on dentition within a specified salivary group. However, the total number of microorganisms and the proportions of veillonellae, actinomycetes, streptococci and S. salivarius were significantly reduced in xerostomic patients not using artificial saliva, whereas lactobacilli, Candida and S. mitior were significantly increased compared to the control groups. Ad libitum use of artificial saliva had little effect, but semi‐continuous wetting of the oral cavity through an intra‐oral reservoir reversed the xerostomia‐induced shifts in the indigenous microflora. However, no significant effect was observed on the proportions of lactobacilli and yeasts, leaving a potentially acidogenic flora.
Scanning electron microscopic study of Warthin's tumor
Authors: Hwang B. T. , Sugihara K. , Kawashima K. , Yamashita S.
Published: April 2006

Three cases of Warthin's tumors were studied with a scanning electron microscope. The free surface of the epithelium was composed mainly of round or ovoid dome‐like structures bearing microvilli and apocrine protrusions. Ciliated epithelial cells were detected in 2 of the tumors. The tumor epithelium encircled various amounts of cellular debris resembling degenerate lymphoid cells. A few tiny cystic spaces were also found. Within the lymphoid stroma, tightly packed lymphocytes, a meshwork of reticulum cells and medullary cord‐like structures were observed. Our findings support the concept that Warthin's tumors develop from heterotopic salivary gland ducts within pre‐existing lymph nodes.
A comparative study of the clinical and histological features of recurrent and nonrecurrent odontogenic keratocysts
Authors: Woolgar J. A. , Rippin J. W. , Browne R. M.
Published: April 2006

Abstract ‐ The clinical features of 44 recurrent odontogenic keratocysts were compared with those of 228 single non‐recurrent keratocysts which had been followed for 5 or more years. Histological comparisons were made with 44 nonrecurrent cysts matched for age, sex and site. There were no significant differences in the age, sex and site between patients with recurrent and nonrecurrent cysts. There were no significant histological differences except for a greater amount of inflammation in the non‐recurrent cysts. It is suggested that operative factors have a major influence on the likelihood of recurrence.
DNA‐ploidy studies in a keratocyst undergoing subsequent malignant transformation
Authors: High A. S. , Quirke P. , Hume W. J.
Published: April 2006

Using techniques that allow flow cytometry to be performed on tissue stored in paraffin wax, we have examined the DNA content of cells from an odontogenic keratocyst which underwent malignant transformation. On histological examination, the primary lesion was an odontogenic keratocyst showing dysplastic changes within the squamous epithelium. Flow cytometry revealed a prominent, abnormal DNA stemline, which was also present in the subsequent squamous cell carcinoma.
Melanotic neuroectodermal tumor of infancy with high serum levels of alpha‐fetoprotein Ultrastructural study and immunological evidence of glial fibrillary protein and alpha‐fetoprotein
Authors: Dourov N. , Mayer R. , de Martelaere F. , Godart S. , Gepts W. , Maurus R.
Published: April 2006

We report an infant melanotic neuroectodermal tumor in the anterior part of the upper gingiva, which was associated with high urinary excretion of vanilmandelic acid. Scrum levels of alpha‐fetoprotein were abnormally high (200 ng/ml). They returned to normal after removal of the tumor (10 ng/ml). The tumor was characterized historically and ultrastructurally by the presence of melanocytic and astrocytic cells containing glial fibrillary protein. Intracellular alpha‐fetoprotein was demonstrated by the immunoperoxydase method (PAP) in scattered foci of interstitial cells.
Surface ultrastructural changes in chemically induced premalignant lesions in the hamster cheek pouch
Authors: Hassanin M. B. , Ashrafi S. H. , Das A. K.
Published: April 2006

The histopathological and topographical alterations occurring during the early stages of chemical carcinogenesis in the hamster cheek pouch using 7, 12‐dimethylbenz (α) anthracene (DMBA) were studied by light and scanning electron microscopy. At the scanning electron microscopic level, cellular overlapping and mild disturbance of intercellular bridges were noticed as early as the second week of DMBA application; these changes progressed with time. Clear epithelial dysplastic changes at the light microscopic level were detected by the sixth week of the experiment. The results of this investigation demonstrate the usefulness of scanning electron microscopy as an adjunct tool to study early alterations in cell morphology which occur in the stratified squamous epithelium of the hamster cheek pounch in response to a chemical carcinogen.
Immunohistochemical analysis of cells in mucosal lesions of oral lichen planus
Authors: Takeuchi Y. , Tohnai I. , Kaneda T. , Nagura H.
Published: April 2006

We immunohistochemically analyzed the immunological background of the pathogenesis of oral lichen planus (OLP). Abundant lymphocytes infiltrated OLP mucosal lesions, particularly in satellite cell necrosis (SCN) regions, and cytotoxic/suppressor T lymphocytes were predominant in seven of 10 OLP cases. Some carried IL‐2 receptors, particularly in SCN. Keratinocytes of the mucosal lesions expressed both HLA‐ABC and HLA‐DR antigens. This suggests that activated cytotoxic/suppressor T lymphocytes may play a major role in cytotoxity to keratinocytes as effector cells in OLP. OKM1‐, OKM5+, HLA‐DR+ and IL‐1+ cells, vascular endothelial cells and clusters of spindle‐shaped or oval cells, which had the same surface characteristics as a monocyte macrophage subset, were abundant and, together with migrating lymphocytes, might play a role in the immune response in mucosal lesions of OLP.
Immunoelectron microscopical localization of immunoglobulins, secretory component and J chain in the human minor salivary glands
Authors: Sumi Y. , Nagura H. , Kaneda T. , Oka T.
Published: April 2006

Localization of IgA, secretory component (SC) and J chain was investigated immunocytochemically in minor salivary glands of the lip and palate to define the mechanism involved in the transport of immunoglobulin A (slgA) into the saliva from the minor salivary glands. SC synthesis was detected in mucous acinar cells and ductal epithelial cells. Free SC is secreted into the saliva through secretory granules in the mucous acinar cells. Dimeric IgA containing J chain is translocated through these cells as slgA by a SC‐medialed transport mechanism involving cytoplasmic vesicles.
The in vitro cytotoxic effect of leukocytes from patients with recurrent aphthous ulceration upon mouse 3T3 fibroblasts
Authors: Thomas D. W. , Bagg J. , Walker D. M.
Published: April 2006

This study compared the in vitro cytotoxic activity against cultured NIH 3T3 mouse fibroblasts of peripheral blood leukocytes (PEL) from 13 patients with minor recurrent aphthous ulceration (RAU), 5 patients with non‐aphthous oral ulceration and 23 age‐ and sex‐matched healthy control subjects. Leukocytes from patients with RAU exerted a significantly greater degree of cytotoxicity towards the 3T3 cells than did those of control subjects. This enhanced cytotoxicity was abrogated by depletion of PEL bearing the CDS antigen (T‐lymphocytes). In contrast, PEL from patients with non‐aphthous oral ulceration failed to exert an enhanced cytotoxic activity against 3T3 fibroblasts, when compared to PEL from healthy control subjects. It was concluded that PEL from patients with RAU exert a significantly enhanced cytotoxicity towards an unrelated xenogeneic target cell. This activity is a specific feature of RAU and in the assay system described appears to be mediated by T‐lymphocytes.
Postmortem pink teeth: in vitro production
Authors: van Wyk C. W.
Published: April 2006

The aim of this study was to produce pink teeth experimentally with cadaver blood and to correlate the time sequence of the coloration with the pattern of hemolysis of the blood. The blood from 7 cadavers (postmortem period 8–58 h) was used to stain 7 groups of 14 teeth each. All the teeth were divided longitudinally and one half received blood which contained a piece of skin (to imitate pulpal autolysis) and the other half cadaver blood only. Circumpulpal discoloration commenced on the sixth day postmortem and increased to 18 days. At 6 days, hemolysis was evident histologically and the separation between plasma and blood cells had disappeared in centrifuged blood. No difference was noticed between the blood with and without skin. It is concluded that pink staining of teeth can only occur after hemolysis and that discoloration becomes obvious macroscopically at about 6 days.
Chondrosarcoma. II. Chondrosarcoma of the jaws: analysis of 37 cases
Authors: Garrington G. E. , Collett W. K.
Published: April 2006

Analysis was made of 37 cases of Chondrosarcoma of the maxilla or the mandible. The most common complaint at initial presentation was the presence of a mass. Pain was a presenting symptom in less than half of the patients. The usual roentgenographic appearance was an ill‐defined radiolucency with mottled areas of calcification. When teeth were involved, some cases showed a widened periodontal membrane space on periapical dental radiographs. Histologically, the tumors usually showed recognizable cartilage and a lobular growth pattern, but cellular evidence of malignancy was often subtle. Radical surgery was the treatment of choice. Prognosis appears best when such surgery is performed soon after the onset of symptoms. Also, patients presenting with mandibular tumors and with tumors of the better differentiated histologic grades enjoy a better survival time. Neck dissection is probably not warranted for Chondrosarcoma of the jaws. Contrary to the relationship between these two tumors in other skeletal sites, the overall prognosis for Chondrosarcoma of the jaws does not appear to be as good as that for osteosarcoma of the jaws.
Histochemical studies on glycosaminoglycans of odontogenic cysts
Authors: Smith G. , Smith A. J. , Browne R. M.
Published: April 2006

Histochemical examination of odontogenic cyst connective tissue has demonstrated that hyaluronic acid is the predominant glycosaminoglycan present with lesser amounts of the sulphated glycosaminoglycans. Mast cells were frequently observed in the connective tissue, particularly just beneath the epithelium and may be responsible for the enhanced staining for heparin observed in this area. Local tissue metabolism and inflammation will contribute to the release of glycosaminoglycans from connective tissue into the lumenal fluid. Staining of glycosaminoglycans was generally minimal in the epithelium, although hyaluronic acid and chondroitin sulphate were detected in goblet cells. Glycosaminoglycans previously demonstrated in cyst fluids are probably derived from several sources in the cyst and will be important in its expansile growth.
Osteoclast activating factor is now interleukin‐1 beta: historical perspective and biological implications
Authors: Jandinski J. J.
Published: April 2006

Interleukin‐1 (IL‐1) represents a family of polypeptides with widespread immunological and non‐immunological activity. Recent studies show that Osteoclast activating factor (OAF) is homologous to IL‐1B. In this review, the biological properties, cell sources and actions of IL‐1 are discussed. The numerous biological effects of IL‐1 on various host systems suggest that elevated levels of the mediator may be an indicator of a pathological process. Since the IL‐1 family plays an important role as a key mediator of the inflammatory, immunological and bone resorptive responses it is of considerable concern to dentists.
Resolution of candidal lesions of the dorsal rat tongue by ketoconazole
Authors: Allen C. M. , Rossie K. M. , Haring J. I. , Beck F. M.
Published: April 2006

The purpose of this study was to determine whether the mucosal alterations of the dorsal rat tongue produced by Candida albicans infection were reversible upon treatment with the antifungal drug ketoconazole. Following experimentally‐produced infection, 17 rats showed clinical evidence of persistent lesions over a period of 20 weeks. Eight of these animals were then treated with ketoconazole daily for 2 weeks (20 mg/kg/day). Appropriate non‐infected controls and ketoconazole‐only controls were also maintained. Five weeks after the ketoconazole treatment, all animals were killed and the dorsal tongues evaluated clinically and histologically. Control groups showed no abnormalities. Of the 8 animals in the treated‐lesion group, all showed lesional resolution, while only 2 of the 9 animals in the untreated‐lesion group showed resolution of their lesions (p=0.002). These findings indicate that the epithelial changes produced by this candidal isolate for this period of time are reversible.
Study of AIDS‐related lymphadenopathy in the intraparotid and perisubmaxillary gland lymph nodes
Authors: Poletti A. , Manconi R. , Volpe R. , Carbone A.
Published: April 2006

Salivary gland lymph node involvement is rare in patients at risk for AIDS. Intraparotid and perisubmaxillary gland lymph node biopsies from 2 intravenous drug abusers serologically positive for human immunodeficiency virus (HIV) affected by persistent generalized lymphadenopathy (PGL) were also analyzed immunohistologically. We found hypervascular reactive lymphoid hyperplasia with prevalence of suppressor T‐cells within follicular centers often lacking surface IgD‐positive mantle zone cells and showing disruption of the network of dendritic reticulum cells revealed with DRC‐1 and anti‐S‐100 protein antibodies. Within the nodes there were numerous cysts lined by metaplastic squamous epithelium/positive for epithelial membrane antigen and containing numerous lymphocytes positive for leukocyte common antigen, macrophages positive for alpha1 ‐antichymotrypsin, and Langerhans cells positive for OKT6. Salivary gland lymph nodes are immunohistologically similar to those of other sites in PGL and their increased epithelial metaplastic component containing cells involved in the immune response might represent an exuberant reaction to HIV infection.
Immunohistochemical staining for vimentin filaments and S‐100 protein in myxoma of the jaws
Authors: Lombardi T. , Kuffer R. , Bernard J.‐P. , Fiore‐Donno G. , Samson J.
Published: April 2006

Two jaw myxomas have been analyzed by a panel of antibodies to characterize this tumour type. Vimentin, but not keratin, neuron‐specific enolase (NSE), glial fibrillary acidic protein (GFAP), neurofilament (NF), desmin and Factor VIII‐related antigen (FVIII‐AG), demonstrated positivity in the cytoplasm of the neoplastic cells. Moreover, an antibody against S‐100 protein also showed a strong positive reaction in the cytoplasm of the tumour cells examined. Thus directly indicating a mesenchymal derivation for odontogenic myxoma, and is the first demonstration of S‐100 protein within the cells of this tumour type.
Patterns of keratin‐expression in rests of Malassez and periapical lesions
Authors: Gao Z. , Mackenzie I. C. , Williams D. M. , Cruchley A. T. , Leigh I. , Lane E. B.
Published: April 2006

Using immunocytochemistry and a panel of monoclonal antibodies directed against various keratin polypeptides we examined specimens of normal periodontal ligament, periapical granulomas and inflammatory dental cysts. Epithelial elements with the appearance of rests of Malassez were identified in 6 specimens of normal periodontium and 10 periapical granulomas. Altered epithelium was present in 16 periapical granulomas and a lining epithelium in 10 inflammatory dental cysts. The patterns of binding of antibodies by these epithelia indicated that (a) keratin 19 was expressed by all epithelia, and (b) rests of Malassez also expressed keratin 5 but not large amounts of other keratins and (c) epithelial proliferation in periapical lesions was associated with increased expression of keratin 14, a marker of stratifying epithelia, new expression of keratins 4 and 13, differentiation markers for non‐cornifying epithelia and variable, low levels of keratins 8 and 18, markers of simple epithelia. Proliferation of the epithelial rests of Malassez to form the lining of inflammatory dental cysts thus appears to be associated with a change from an unusual epithelial phenotype to that of a stratified non‐cornifying epithelium in which some simple epithelial keratins are coexpressed.
Mechanisms of carcinogenesis with particular reference to the oral mucosa
Authors: Boyd N. M. , Reade P. C.
Published: April 2006

Three types of stimulus, chemical, physical and viral, are known to be carcinogenic to susceptible animals. This review considers these stimuli and their possible mechanisms in general terms and their possible relevance to the induction of oral mucosal carcinoma in particular.
Factors associated with the development of neoplasia
Authors: Boyd N. M. , Reade P. C.
Published: April 2006

A number of factors have been associated with the development of the phenotypic expression of neoplastic disease. The following article reviews the evidence implicating these factors in carcinogenesis and considers them under the groupings of familial or genetic factors, dietary factors, hormonal factors, age and gender.
Immunohistochemical localization of intermediate filament proteins in calcifying epithelial odontogenic tumors
Authors: Mori M. , Tatemoto Y. , Yamamoto N. , Okada Y.
Published: April 2006

Three calcifying epithelial odontogenic tumors (CEOT) were examined immunohistochemically. The localization of intermediate filaments was characterized through the use of polyclonal anti‐keratin antiserum (TK which detects 41–65 kd keratins), 2 monoclonal keratin antibodies (PKK1 specific for the 44, 46, 52 & 53 kd keratins and KL1, specific for the 55–57 kd keratins) and monoclonal antibodies for vimentin and desmin. The tumor epithelial cells were slightly positive or negative for PKK1 detectable keratins, but slightly to strongly positive for KL1 and TK antibodies. Tumor epithelium was slightly positive for vimentin but negative for desmin. The tumor foci were composed of both dark‐staining and pale‐staining cells; the former had a more intense reaction with KL1 and TK antibodies than the latter. Homogeneous acellular material was either PAS‐positive or negative, with or without calcification, and keratin‐negative.
Effects of epidermal growth factor and nerve growth factor on isoproterenol‐induced DNA synthesis in rat parotid and pancreas following removal of submandibular‐sublingual glands
Authors: Schneyer C. A. , Humphreys‐Beher M.
Published: April 2006

When epidermal (EFG) (10 ng/kg body wt) or nerve growth factor (NGF) (1 ng/kg body wt) was given intraperitoneally to sialadenectomized young rats (submandibular‐sublingual (SM‐SL) glands removed) prior to injection of isoproterenol (ISO) (50 mg/kg body wt), the inhibition of ISO‐induced thymidine incorporation into DNA of parotid gland and pancreas caused by removal SM‐SL glands was reversed, and thymidine incorporation of sialadenectomized ISO‐treated organs was as high as that of parotid and pancreas of surgically intact animals given ISO. EOF alone caused an increase in [3H] thymidine incorporation into DNA of parotid (63%) and pancreas (59%); removal of the SM‐SL glands caused a decrease of 57–70% in thymidine incorporation into DNA of parotid, pancreas, liver, lung, kidney, and spleen. A growth effect attributable to the EGF and NGF of the submandibular gland was thus apparent for all organs examined, but even if they had large complements of β1, adrenoceptors, only the exocrine organs showed the ISO‐induced β1, adrenoceptor response to EOF and NGF. EGF and NGF thus interact only with β1 adrenoceptors of exocrine organs to cause marked increase in [3H] thymidine incorporation of these organs.