Gigantiform cementoma: clinicopathologic presentation of 3 cases

Gigantiform cementoma is a rare, benign fibro-cemento-osseous disease of the jaws, seen most frequently in young girls. Radiographically, it typically presents as multiquadrant, expansile, mixed radiolucent-opaque lesions that cross the midlines of the jaws. Although cases with a familial pattern are noted in a few publications, sporadic cases have been reported without a family history. The term gigantiform cementoma has been used interchangeably with designations of other fibro-osseous entities, yet its application should be restricted by the criteria defined herein. In this article, we report 3 cases of gigantiform cementoma. Clinical, radiographic, and microscopic features of these lesions are presented, along with criteria to differentiate gigantiform cementoma from other fibro-osseous diseases of the jaws. A possible pathogenetic mechanism and treatment recommendations are discussed.

Papillary lesions of the oral cavity: relationship to human papillomaviruses

Human papillomaviruses are a group of genetically related organisms that infect stratified squamous epithelium. Unlike many other viruses that infect oral epithelium and induce lysis of the cells they penetrate, HPVs induce proliferative changes in these cells that result in both benign and malignant tumors. The common skin wart (verruca vulgaris) is induced by HPV 2 and 4. Genital warts (condylomas) and the common solitary oral papilloma are associated with HPV 6 and 11. Either HPV 13 or 32 causes focal epithelial hyperplasia. All of these wart-like lesions are benign growths of the stratified squamous lining of the oral cavity and lips and can be treated by surgical excision or laser ablation. HPV 16 and other less frequently encountered genotypes are associated with uterine cervix cancer in 95 percent to 98 percent of cases, and the evidence for a causal role is robust. There are emerging data that implicate HPV in certain subsets of oral cancer, particularly those that arise in the oropharynx/tonsillar region. Some instances of the various histologic subtypes subsumed under proliferative verrucous leukoplakia and verrucous carcinoma also harbor HPV.

A laser-powered hydrokinetic system for caries removal and cavity preparation

BACKGROUND

Laser systems have been developed for the cutting of dental hard tissues. The erbium, chromium:yttrium-scandium-gallium-garnet, or Er,Cr:YSGG, laser system used in conjunction with an air-water spray has been shown to be efficacious in vitro for cavity preparation.

METHODS

The authors randomly selected subjects for cavity preparation with conventional air turbine/bur dental surgery or an Er,Cr:YSGG laser-powered system using a split-mouth design. They prepared Class I, III and V cavities, placed resin restorations and evaluated subjects on the day of the procedure and 30 days and six months postoperatively for pulp vitality, recurrent caries, pain and discomfort, and restoration retention. Sixty-seven subjects completed the study.

RESULTS

There were no statistical differences between the two treatment groups for the parameters measured with one exception; there was a statistically significant decrease in discomfort levels for the laser system at the time of cavity preparation for subjects who declined to receive local anesthetic.

CONCLUSIONS

The Er,Cr:YSGG laser system is effective for preparation of Class I, III and V cavities and resin restorations are retained by lased tooth surfaces.

CLINICAL IMPLICATIONS

Hard-tissue cutting lasers are being introduced for use in operative dentistry. In this study, an Er,Cr:YSGG laser has been shown to be effective for cavity preparation and restoration replacement.

Sanguinaria-associated oral leukoplakia: comparison with other benign and dysplastic leukoplakic lesions

OBJECTIVE

This study was undertaken to compare and contrast biomarkers and ploidy data from maxillary gingiva leukoplakias associated with dentifrices and mouthrinses containing the herbal compound sanguinaria with other forms of oral benign and premalignant mucosal keratosis.

STUDY DESIGN

Representative archived specimens of benign keratosis, sanguinaria-associated keratosis, and keratosis with dysplasia were used for computerized image analysis and biomarker immunohistochemical assays to assess ploidy, DNA content, and p53 and proliferating cell nuclear antigen immunoreactivity of nuclei.

RESULTS

DNA content was significantly higher and higher numbers of cell populations with hyperploid nuclei were encountered in the dysplastic group than in the other two groups (P <.001). Sanguinaria-associated keratosis did not harbor significant numbers of p53-expressing nuclei, yet it showed a significant elevation in proliferating cell nuclear antigen-labeled nuclei in total, in the basal layer, and in the spinous layer in comparison with benign keratoses (P <.001). In addition, 1.5% of the sanguinaria-associated leukoplakia epithelial cell population was characterized by nuclei with a greater than 4-fold increase in DNA content.

CONCLUSIONS

Sanguinaria-associated keratoses show some marker and image analysis profiles similar to those of non-sanguinaria dysplastic lesions of the lip and mucosa. Preparations containing sanguinaria should be avoided until the risk for malignant transformation is determined.

Malignant epithelial odontogenic tumors

Malignant epithelial odontogenic tumors are very rare. They may arise from the epithelial components of the odontogenic apparatus. The rests of Malassez, the reduced enamel epithelium surrounding the crown of an impacted tooth, the rests of Serres in the gingiva, and the linings of odontogenic cysts represent the precursor cells for malignant transformation. Because metastatic carcinoma is the most common malignancy of the jaws, the diagnosis of a primary intraosseous carcinoma must always be made to the exclusion of metastatic disease. Odontogenic carcinomas include malignant (metastasizing) ameloblastoma, ameloblastic carcinoma, primary intraosseous squamous cell carcinoma, clear cell odontogenic carcinoma, and malignant epithelial ghost cell tumor. There are specific histopathologic features that support the diagnosis of a primary carcinoma of odontogenic epithelium which are presented in this article. Immunohistochemical (IHC) staining is important for distinguishing clear cell odontogenic carcinoma from metastatic renal cell tumors, yet IHC stains are not particularly helpful for other lesions in this group-all of which exhibit low molecular weight cytokeratin positivity. Aggressive growth and nodal and distant metastases occur with all of these entities.

Topographical characteristics and shear bond strength of tooth surfaces cut with a laser-powered hydrokinetic system

STATEMENT OF PROBLEM

Erbium lasers, specifically Er;YAG and Er, Cr;YSGG that emit in the near red wavelengths, cut both enamel and dentine. Bonding to these cut surfaces with composites has not been assessed for all laser systems.

PURPOSE

This investigation assessed the shear bond strength of composite bonded to tooth structure treated with an Er,Cr;YSGG-powered hydrokinetic system (HKS, Millennium system) and then was compared with surfaces treated with a carbide bur.

MATERIAL AND METHODS

Extracted human molars were cut into enamel and dentin with both systems. Nonetched and acid-etched subgroups were evaluated. Shear bond strength was measured with an Instron test machine with a knife-edge loading head. In addition, SEMs were evaluated.

RESULTS

There were no significant differences in shear bond strength between etched bur cut (23.3 +/- 2.5 MPa), etched laser-cut enamel (23.7 +/- 4.5 MPa), and nonetched laser-cut enamel (20.5 +/- 2.8 MPa). For nonetched enamel, bond strength values for laser-cut surfaces were significantly higher than the bur-cut surfaces (8.7 +/- 4.3 MPa). Bond strength differences for dentin between bur (14.3 +/- 1.7 MPa) and laser cuts (11.5 +/- 4.3 MPa) were not significant (P =.03). SEM revealed that laser cutting of enamel did not cause formation of a smear layer.

CONCLUSION

There were no significant differences in shear bond strength between etched bur-cut, etched laser-cut, and nonetched laser-cut enamel. With nonetched enamel, bond strength values for nonetched laser-cut surfaces were significantly higher than for the bur-cut surfaces. No bond strength differences between bur and laser cutting existed for dentin. Similar topography was observed for bur and laser prepared surfaces of etched enamel and nonetched dentin.

Two approaches to the diagnosis of lesions of the oral mucosa

This article describes two approaches to the classification of oral mucosal lesions. One is based on the etiopathogenesis of the lesion and the second on the clinical appearance. These two approaches are compared and contrasted, and their integration is described. Combining these two classification schemas allows an excellent understanding of the various lesions so than an expeditious and correct diagnosis can result. Appropriate management and treatment can then follow.

Nodular fasciitis and solitary fibrous tumor of the oral region: tumors of fibroblast heterogeneity

OBJECTIVE

Fibroblastic proliferations of the oral cavity are extremely varied, yet they share certain features-spindle cell morphology, collagen synthesis, and fasciculation. Nodular fasciitis is a cellular fibroblastic lesion, uncommonly located in the oral submucosa, that shows smooth muscle actin (SMA) immunoreactivity. Solitary fibrous tumor expresses a CD34 fibroblast phenotype. The aim of this study is to report instances of nodular fasciitis and solitary fibrous tumor in the orofacial region and investigate immunohistochemical markers to compare and contrast fibroblastic phenotypic heterogeneity in these tumors.

STUDY DESIGN

Seven benign cellular fibrogenic tumors initially diagnosed as nodular fasciitis over a 10-year period were examined. Immunohistochemical markers, including S-100 protein, SMA, CD68, CD34, and vimentin, were used to further characterize these lesions.

RESULTS

All tumors occurred in adults, and the buccal mucosa was found to be the favored site. The spindle cells in these tumors showed phenotypic heterogeneity both within and between tumors. All were vimentin-reactive and harbored small populations of CD68-positive macrophage/dendrocytes. Five tumors were SMA-positive and CD34-negative; the tumor in one case was SMA-negative and CD34-positive, and that in another was SMA-positive and CD34-positive.

CONCLUSION

Although rare, nodular fasciitis and solitary fibrous tumor arise in oral submucosa, usually in the cheek. The histopathologic features and immunomarkers indicative of myofibroblastic differentiation are seen in nodular fasciitis, whereas solitary fibrous tumor is CD34-positive; however, one instance was found to be positive for both markers. All of these cases harbored subpopulations of CD68-positive cells. Immunomarkers are a valuable adjunct in differentiating nodular fasciitis from solitary fibrous tumor, yet some tumors may harbor heterogeneous fibroblast phenotypes.

Human papilloma virus type 16 E6 gene expression in oral exophytic epithelial lesions as detected by in situ rtPCR

OBJECTIVE

We adopted an in situ reverse transcriptase polymerase chain reaction method of detecting and determining the frequency of early (E6) gene expression of human papilloma virus type 16 at the individual cell level in a sample of oral exophytic lesions with various degrees of epithelial hyperplasia and dysplasia in immunosuppressed and immunocompetent patients.

STUDY DESIGN

The significance of differences between the study groups was determined by Mantel-Haenszel chi-square analysis and calculation of odds ratios, accounting for immunosuppression and degree of dysplasia, respectively.

RESULTS

Grouped together, the lesions of dysplasia (mild to severe) and squamous cell carcinoma were found to be 16 times more likely to express human papilloma virus E6 mRNA than the benign lesions (P = .0013); in the lesions of immunosuppressed patients, human papilloma virus 16 E6 was roughly 10 times more likely to be expressed than in those of the immunocompetent patients (P = .0008, accounting for dysplasia).

CONCLUSIONS

Our data indicate that human papilloma virus 16 E6 gene expression, and perhaps integration of the virus in the host genome, might play a role in the development of oral neoplasia in association with immunosuppression.

Pulpal thermal responses to an erbium,chromium: YSGG pulsed laser hydrokinetic system

PROBLEM

Laser systems are known to raise pulpal temperatures when applied to tooth surfaces. Dental biocalcified tissues can be cut with an erbium,chromium:yttrium-scandium-gallium-garnet laser-powered hydrokinetic system. This device is effective for caries removal and cavity preparation in vitro. Pulpal monitoring of temperature changes during hard tissue cutting by a hydrokinetic system have not been reported.

OBJECTIVES

This study compared the effects of hydrokinetic system, dry bur, and wet bur tooth cutting on pulpal temperature.

STUDY DESIGN

In vivo thermocouple intrapulpal measurements were made on cuspid teeth in anesthetized beagle dogs. In vitro measurements were made on extracted human molar teeth preserved in high-salt solution and later rinsed in phosphate-buffered saline (pH 7.4) to simulate in vivo conditions. The hydrokinetic system was compared with conventional air-turbine-powered bur cutting. The hydrokinetic system cuts and bur preparations were randomly made on the buccal surfaces at the cervical one third of the crown and extended until exposure of the pulp was confirmed clinically.

RESULTS

Pulpal temperatures associated with the hydrokinetic system either showed no change or decreased by up to 2 degrees C. Wet bur preparations resulted in a 3 degrees to 4 degrees C rise. With dry bur preparations, a 14 degrees C rise in temperature was recorded.

CONCLUSIONS

Under the conditions of this study, the erbium,chromium:yttrium-scandium-gallium-garnet laser-powered hydrokinetic system, when used for cavity preparation, had no apparent adverse thermal effect as measured in the pulp space.

Immunopathogenesis of oral lichen planus and recurrent aphthous stomatitis

Oral mucosal bullous/desquamative/ulcerative diseases involve immunopathological mechanisms that account for loss of adhesion between contiguous keratinocytes or to structures within the basal lamina. Some are antibody mediated, in which specific adhesion molecules of the desmosome, hemidesmosome, and basement membrane become antigenic targets. Oral lichen planus and recurrent apthous ulcers, although manifesting disparate clinical appearances and natural history, share immunopathological features that involve T cell-mediated immunity. Although the antigens, haptens, or autoantigens are not usually apparent, current research poses the hypothesis that both of these common oral mucosal diseases are a delayed-type hypersensitivity or cell-mediated response to an antigenic stimulus residing within the epithelium. This article reviews the research evidence for this hypothesis.

Oral keratinocyte immune responses in HIV-associated candidiasis

INTRODUCTION

Candidiasis is the most commonly encountered opportunistic infection among HIV-positive subjects. The purpose of this study was to assess specific keratinocyte immune parameters in the pseudomembranous and erythematous forms of HIV-associated oral candidiasis.

MATERIAL/METHODS

This collaborative study from three centers analyzed 25 HIV-positive and 10 HIV-negative subjects with either pseudomembranous or erythematous candidiasis. Oral biopsy specimens from lesional tissues were procured, and histopathologic features were correlated with immunohistochemical and in situ hybridization investigations for the expression of interleukin 1 alpha, interleukin 8, antimicrobial calprotectin, lymphocyte populations, and Candida antigen.

RESULTS

Both pseudomembranous and erythematous candidiasis among HIV-infected subjects showed a mild interface lymphocytic mucositis with the presence of neutrophilic subcorneal abscesses in the latter. Erythematous candidiasis cases that failed to show surface mycelia, did yield positive results for Candida antigens in the parakeratinized layer. The expression of inflammatory chemokines were positive in all groups and calprotectin appeared to serve as a keratinocyte barrier to hyphal penetration.

CONCLUSIONS

The erythematous form of candidiasis is often devoid of hyphae yet the presence of Candida antigens in the surface epithelium implicates an immune or allergic process. The intactness of chemokines and antimicrobial calprotectin in keratinocytes may explain why disseminated candidiasis is rarely encountered in HIV-infected patients.

Pulpal response to cavity preparation by an erbium, chromium:YSGG laser-powered hydrokinetic system

The near red-pulsed erbium, chromium:yttrium-scandium-gallium-garnet laser hydrokinetic system, or Er,Cr:YSGG laser HKS, is effective in cutting dental hard tissues. In this longitudinal study, the authors studied the continuously erupting open-apex incisors of New Zealand albino rabbits and the constricted apex teeth of beagles to determine the effects of HKS-produced lesions at various energy levels and of preparations produced by a tapered fissure bur on dental pulp. No pulpal inflammatory responses could be identified either immediately or 30 days after surgery in HKS preparations that removed enamel and dentin without pulp exposure.

Immunocompetent cells in oral candidiasis of HIV-infected patients: an immunohistochemical and electron microscopical study

OBJECTIVE

The purpose of this study was to elucidate the pathogenesis of oral candidiasis, a common cause of discomfort and social impairment among HIV-infected individuals.

STUDY DESIGN, MATERIALS AND METHODS

The oral mucosal immune system cells were analysed by immunohistochemistry and electron microscopy in biopsies from five erythematous and four pseudomembranous candidiasis cases and were compared with those from seven HIV-positive and 10 HIV-negative controls without candidiasis.

RESULTS

The superficial lamina propria and basal epithelial layer was populated by CD1a+ Langerhans cells with infiltration of CD8+ lymphocytes. Within the submucosa are CD36+ dendritic macrophages and lymphocytes, although CD4+ subsets were absent from the infiltrate. The expression of human leukocyte antigen system, DR locus (HLA-DR) and leukocyte specific adhesion molecules was low in erythematous, yet more marked in pseudomembranous candidiasis. In the pseudomembranous form, CD14+ leukocytes were found in the basal epithelial layer. Langerhans cells were significantly more numerous and were richer in dendrites and Birbeck granules in erythematous than in pseudomembranous candidiasis.

CONCLUSIONS

Candidiasis is associated with alterations in the number and differentiation of lymphocytes and dendritic cells, being more severe in the pseudomembranous than erythematous form. We propose that these alterations play a role in the pathogenesis and evolution of the disease.

Cellular immune correlates of clinical severity in oral lichen planus: preliminary association with mood states

OBJECTIVES

We investigated cellular immune and psycho-immune dysfunctions in patients with erosive and non-erosive oral lichen planus (OLP) lesions.

METHODS

Patients with erosive or non-erosive OLP were screened at the UCLA Dental Clinic. The profile of mood states (POMS) was administered. T lymphocyte subpopulations were monitored by dual fluorescence. T lymphocytes were stimulated with phytohemagglutinin (PHA) for assessment of markers of activation by flow cytometry and of interleukin (IL)-2 production by ELISA. Plasma cortisol and neopterin levels were assessed by radioimmunoassay.

RESULTS

Circulating T cells that express the cluster of differentiation no. 4 (CD4+) but devoid of the CD45RA marker, and POMS score were significantly associated (r = 0.83, P < 0.05) in the patients we studied. We found a significantly higher (P < 0.05) per cent and absolute lymphocyte numbers of circulating CD4+CD45RA- cells in the OLP patients with erosive lesions, compared to OLP patients with non-erosive lesions. The ratio of CD4+ CD45RA+ over CD4+CD45RA- cells was significantly (P < 0.05) biased toward the CD4+CD45RA- subpopulation in OLP patients with erosive lesions (ratio = 0.19 +/- 0.09) compared to patients with non-erosive OLP lesions (ratio = 0.47 +/- 0.15). The expression of CD54, but not that of CD69, was significantly blunted (P < 0.05) in OLP patients following CD3+ cell stimulation. IL-2 production and plasma neopterin were normal in these patients. There was no correlation between plasma cortisol and T cell populations.

CONCLUSIONS

We find fine differences in psycho-immune interactions between patients afflicted with non-erosive OLP lesions compared to those with erosive OLP lesions.

Histopathology of idiopathic chronic recurrent vertigo

Vestibular neuritis is a degenerative neuropathy of the peripheral vestibular system. The etiology of this condition is uncertain, although it is generally believed to be viral. A small percentage of patients with vestibular neuritis have chronic recurrent episodes of vertigo. Detailed cytologic descriptions of acute or chronic vestibular neuritis are lacking, and no previous studies have reported evidence of chronic inflammation in human temporal bone specimens. The authors of this study examined temporal bone specimens from three patients with a history of chronic recurrent vertigo of unknown cause. Varying degrees of inflammation and destruction were seen in the vestibular system, and mild involvement of the cochlear system was noted. These findings are consistent with postinfectious inflammatory changes of the cochlear-vestibular system analogous to a postinfectious syndrome involving the central nervous system.

Effects of an erbium, chromium: yttrium, scandium, gallium, garnet laser on mucocutanous soft tissues

OBJECTIVES

Lasers are effective tools for soft tissue surgery. The erbium, chromium: yttrium, scandium, gallium, garnet laser is a new system that incorporates an air-water spray. This study evaluates the cutting margins of this laser and compares healing with laser and conventional scalpel and punch biopsy-induced wounds.

STUDY DESIGN

New Zealand white rabbits were divided into serial sacrifice groups; the tissues were grossly and microscopically analyzed after laser and convential steel surgical wounding.

RESULTS

Wound margins were found to show minimal edge coagulation artifact and were 20 to 40 mm in width. Laser wounds showed minimal to no hemorrhage and re-epithelialization and collagenization were found to occur by day 7 in both laser and conventional groups.

CONCLUSIONS

The new laser system is an effective soft tissue surgical device; wound healing is comparable to that associated with surgical steel wounds. The minimal edge artifact observed with this laser system should allow for the procurement of diagnostic biopsy specimens.

Cause of oral ulcers in HIV-infected patients: a study of 19 cases

OBJECTIVES

To study the cause and clinical aspects of oral ulcers in HIV-infected patients.

STUDY DESIGN

Forty-one consecutive HIV-positive patients with long-standing oral ulcers were examined; 19 were evaluated by biopsy. From these 19 cases, viral, bacterial, and fungal cultures and biopsies were taken in each patient. When indicated, special microbial stains were undertaken to identify bacteria or fungi. Ten cases without granulomatous bacterial fungal or lymphomatous features were available for in situ hybridization to detect viral DNA of herpes simplex virus 1 and 2, cytomegalovirus, varicella-zoster virus, and Epstein-Barr virus.

RESULTS

Most of the oral ulcers occurred in patients with severe immunodepression. Median CD4 T-lymphocyte count was 60 cell/mm3 (range, 3 to 335). It was ascertained that nine (47%) patients had nonspecific aphthous-like ulcers, and ulcers caused by herpes group viruses were identified in six (31.5%) patients. One (5%) person was diagnosed with non-Hodgkin's lymphoma; and in one (5%) patient, multiple ulcers were an expression of lues maligna. Two ulcers (10.5%) in the palate harbored mycotic granulomatous foci (cryptococcosis, histoplasmosis). In this population, almost all of these ulcers were found to be large, persistent, and painful.

CONCLUSIONS

Nontumefactive oral ulcers in HIV-positive patients may be a source of diagnostic difficulties because of the diverse array of underlying pathologic entities and multiplicity of etiologic agents. Biopsy should always be performed on long-standing ulcers because either infection or a neoplastic process may be extant. In the absence of infection or neoplasm, such lesions are then designated as ulcers not otherwise specified.

Oral lichen planus and its association with squamous cell carcinoma: an update on pathogenesis and treatment implications

Lichen planus of the oral mucosa (OLP) is characterized by lymphocytic mucositis, basal cell lysis, and lymphocyte transmigration into the epithelial compartment. Some reports have suggested a high incidence of oral squamous cell carcinoma (OSCCA) in OLP patients and have implicated OLP as a premalignant lesion. We describe five cases of OSCCA arising in patients with preexisting OLP. At our institution, the incidence of OSCCA in patients with OLP approximates that reported in other series. The immunopathologic basis for OLP, its potential association with malignancy, and the variable clinical picture of OSCCA in patients with OLP are reviewed. Specific recommendations are given for treatment and follow-up of lesions, including the role of future testing with viral and oncogene markers.

Herpes simplex and cytomegalovirus coinfected oral ulcers in HIV-positive patients

Four HIV-positive patients with herpes simplex virus and cytomegalovirus coinfected oral ulcers are presented. All patients had persistent oral pain associated with nonhealing mucosal ulcers. Lesions occurred on the palate, retromolar pad, tongue, and lip, and the clinical appearance of the ulcers was nonspecific. Histologic and immunohistochemical stains showed herpes simples virus alterations in keratinocyte nuclei and cytomegalovirus alterations in mesenchymal/endothelial cell nuclei and cytoplasm. Lesions in one patient responded to ganciclovir therapy. One patient improved with acyclovir, and another healed normally after excisional biopsy. Each virus alone has been described as causing oral ulcerations; their appearance together in the same lesion would suggest a synergistic relationship.

Preliminary investigations on the utility of an erbium, chromium YSGG laser

A variety of laser systems are under investigation as potential tools in dentistry. Most of these systems have been shown to be efficacious for soft tissue surgery of the mucous membranes; however, cutting bone and dental hard tissues has only recently been possible. In this report from the University of California at Los Angeles School of Dentistry, a review of laser applications in dentistry is discussed. The utility of a new laser system using an erbium YSGG medium with air water spray to cut soft tissues, bone, enamel and dentin is under investigation and preliminary research findings are presented.

Clear cell odontogenic carcinoma. A clinicopathologic analysis

Clear cell odontogenic tumor is a rare neoplasm of the jaws that histologically may be confused with metastatic renal cell carcinoma. A review of 17 cases revealed that these tumors are aggressive, with a tendency to recur locally after surgery; they also may metastasize both regionally and distantly. There is a marked female predilection, and most cases are discovered during the fifth to seventh decades of life. Seventy percent occur in the mandible, appearing as poorly marginated radiolucencies. We conclude that this tumor is malignant and should be referred to as clear cell odontogenic carcinoma; it requires an aggressive surgical approach.

Papillary squamous neoplasms of the head and neck

Papillary squamous neoplasms of the upper respiratory tract are rare variants of squamous cell carcinoma and are related temporally to proliferative verrucous leukoplakia. Fifty-two cases of papillary squamous neoplasms were selected from 2366 cases of squamous cell carcinoma. This is the first study to characterize the biological behavior of papillary squamous neoplasms. Papillary squamous neoplasms exhibit two distinct, yet sometimes overlapping, histologic patterns including an exophytic papillary and an inverting verrucous morphologic appearance. A high rate of synchronous or metachronous lesions were found, especially with the inverting-type of papillary squamous neoplasm. Stage T3 and T4 lesions had a high rate of neck metastasis. Early surgical intervention and close long-term follow-up is mandatory.

Leukocyte adhesion molecules in oral lichen planus: a T cell-mediated immunopathologic process

Oral lichen planus exhibits features of a mucosal type IV immunopathologic process. Adhesion molecules involved in the trafficking and homing of T lymphocytes to the subepithelial compartment were assessed by immunohistochemical methods. Laminin, type IV collagen and type VII collagen extracellular matrix components at the epithelial-connective tissue junction are significantly increased and serve as ligands for beta 1 integrins on lymphocyte membranes. Endothelial-associated intercellular adhesion molecule 1 and extracellular matrix basement membrane components are also significantly increased in the submucosa. Keratinocyte expression of major histocompatibility complex class II molecules and intercellular adhesion molecule 1 may serve as ligands for lymphocyte T cell receptor complex and beta 2 integrins, respectively. These adhesion molecules are probably involved in the trafficking of lymphocytes to the epithelial connective tissue interface in response to as of yet undefined antigens.

Immunopathology of oral mucosal ulcerative, desquamative, and bullous diseases. Selective review of the literature

Cell/cell and cell/matrix adhesion proteins are responsible for maintaining the integrity of the mucosal lining of the oral cavity. Disease processes that destroy keratinocytes or adversely affect their adhesion to one another or to the subjacent basement membrane will result in erosions, ulcerations, and desquamations. Immunologic processes that have a deleterious effect on the integrity of the epithelial/basement membrane/submucosa complex are reviewed, and current research findings with respect to pathogenesis are discussed. In particular, T-cell-mediated hypersensitivity is involved in recurrent aphthous stomatitis and lichen planus; humoral-mediated immunity to cadherin intercellular adhesion molecules is important in the process of acantholysis in pemphigus vulgaris, and genetic defects and antibody-mediated processes give rise to junctional separation in epidermolysis bullosa and mucous membrane pemphigoid, respectively. An immune complex mechanism appears to underlie the pathogenesis of erythema multiforme.

Inflammatory diseases of the mucous membranes. Part 2. Immunopathologic ulcerative and desquamative diseases

Bullous and desquamative diseases of the oral mucosa are not common, with the exception of ulcerative lichen planus. All produce mild to severe mucosal pain and some can be life-threatening. Recent studies have helped elucidate the pathogenesis of immunopathologic diseases, although the precise etiology for most of them remains unknown. Minor and major aphthae, lichen planus, pemphigoid, pemphigus and erythema multiforme are discussed.

Inflammatory diseases of the mucous membranes. Part 1. Viral and fungal infections

With the advent of modern molecular biology and advances in immunology, the pathogenesis of oral mucosal disease processes has become significantly more clear, allowing reliable diagnostic criteria and more precisely targeted management strategies. This paper reviews current findings relative to pathogenesis, diagnosis and treatment of viral and fungal infections of the oral mucous membranes.

The effects of human immunodeficiency virus infection on macrophage phagocytosis of Candida

The effects of infection by human immunodeficiency virus (HIV) on phagocytic function towards Candida pseudotropicalis were tested using monocytotropic and nonmonocytotropic HIV strains on peripheral blood monocytes. There were no differences in either quantitative phagocytic activity or efficacy between the two infected and control mock-infected monocytes. Immunofluorescence for cytoplasmic p24 antigen and in situ hybridization for detection of HIV-specific RNA sequences revealed that very few cells (10(-4)) exhibit productive infection. Occasional cells with active infection as defined by microscopically detectable fluorescence labelling contained phagocytized yeasts.

White lichenoid lesions of the buccal mucosa in patients with HIV infection

We report on eight patients who developed white lichenoid lesions of the buccal mucosa during the course of human immunodeficiency virus infection. In five patients the lesions appeared after the administration of zidovudine, in two after the intake of both zidovudine and ketoconazole, and in one after ketoconazole. In the majority of cases, lesions presented as bilateral reticular keratosis or atrophic changes of the buccal mucosa. Three patients manifested lichenoid atrophic changes of the dorsum of the tongue. The histopathologic features were hyperkeratosis, epithelial atrophy, basal cell liquefaction, and the presence in the lamina propria of either a patchy or diffuse lymphocytic infiltrate. All specimens tested negative for Epstein-Barr virus and human papillomavirus. Our study suggests that lichenoid lesions of the buccal mucosa, similar to what has been described as lichenoid drug reactions or idiopathic lichen planus, can be observed during human immunodeficiency virus infection and that administration of zidovudine and ketoconazole should be considered as a possible cause.

Deep mycoses and palatal perforation with granulomatous pansinusitis in acquired immunodeficiency syndrome: case reports

Palatal perforation with granulomatous pansinusitis caused by deep mycotic infection is a rare complication of acquired immunodeficiency syndrome. Two cases of palatal ulceration with osseous destruction, one caused by Histoplasma capsulatum the other by Cryptococcus neoformans, are discussed. Treatment with a palatal obturator restored function and speech in both patients during the remainder of their lives.

Immunohistochemical mapping of epidermal growth-factor receptors in normal human oral soft tissue

Epidermal growth-factor receptor (EGF-r) has been identified on basilar cells of stratified squamous epithelia and skin adnexa in man. Recent studies have mapped EGF-r to various oral cells in animals; however, complete mapping of EGF-r in normal human oral mucosa has not been done. Normal tissues from eight sites in human oral mucosa were examined for their expression of EGF-r using avidin-biotin peroxidase complex with mouse anti-EGF-r monoclonal antibody. Immunoreactivity was detected in palatal gingiva, buccal gingiva, soft palate, lateral tongue, dorsal tongue and floor of the mouth. The connective tissues of the periodontal ligament and dental pulp were non-reactive. EGF is known to exist in most body fluids, particularly saliva. In normal human mucosa, EGF is localized to connective tissue subjacent to epithelium. With the receptor in the overlying epithelium, a possible epithelial-mesenchymal interaction may exist between the receptor and ligand. A paracrine mode of action may be postulated, functioning to regulate the complex biological functions of the human oral tissues.

Keratinocyte expression of calprotectin in oral inflammatory mucosal diseases

Oral mucosal inflammation evolves in response to microbial pathogens and non-infectious antigens which activate humoral and cell-mediated immunologic processes. Most of these disease processes invoke a leukocyte response culminating in cellular infiltration of the submucosa and, to some degree, transmigration into the epithelium itself. Calprotectin, a leukocyte-derived dimeric protein complex that has potent antibacterial and antifungal effects, has recently been identified in skin and mucosal keratinocytes implying that epithelium may biochemically contribute to the overall mechanism of host defense. In this study, the upregulation of calprotectin as assessed immunohistochemically is pursued for oral diseases of immunopathologic, fungal and viral origin. In lichen planus, candidiasis, herpes virus stomatitis, and oral hairy leukoplakia, calprotectin was found to be expressed to a significantly higher level than in normal control mucosal samples.

On the differential diagnosis of clear cell tumours of the head and neck

Clear cell tumours, both benign and malignant, derive from a diverse group of epithelial cell types including renal epithelium, keratinising epithelium, cutaneous adnexa, salivary glands, odontogenic epithelium, melanocytes and even mesenchymally derived cells of adipose and tendon sheath. In the head and neck, clear cell tumours represent a singular challenge to the pathologist since the classic morphological features of malignant neoplasia exemplified by cytological atypia are frequently absent in malignant clear cell variants, thereby excluding reliance on this histopathological hallmark for the establishment of a diagnosis. The differential diagnosis of both benign and malignant clear cell tumours must take into account patterns of growth as well as the phenotype of accompanying cell populations when attempting to arrive at a definitive histological diagnosis. In this review article, the histopathology of head and neck tumours that harbour significant clear cell populations will be compared and contrasted.

c-myc oncoprotein expression in oral precancerous and early cancerous lesions

Squamous cell carcinoma of the oral cavity is often preceded by clinically evident precancerous lesions. These lesions exhibit progressive cytomorphologic changes connoting cellular transformation to malignant neoplasia. Molecular events underlie the microscopically identifiable cytological changes that herald transformation. Various proto-oncogenes are activated, overexpressed or mutated in the process of transformation. This investigation was designed to determine whether the nuclear binding c-myc oncoprotein, an activator of cell division, parallels or precedes cytomorphological changes at various histologically defined stages in oral precancerous lesions. Employing immunohistological methods, it was determined that c-myc nuclear labelling paralleled the progressive histological changes among various stages of transformation. It was also noted that some, yet not all, instances of benign keratoses which lacked any cytologic evidence of atypia harboured c-myc oncoprotein positive nuclei. It is concluded that c-myc expression is correlated with progressive cell transformation in oral cancerous lesions.

The distribution of the antimicrobial protein, calprotectin, in normal oral keratinocytes

Calprotectin is a heterodimeric peptide isolated from neutrophil cytosol that exhibits profound antimicrobial effects. Using monoclonal antibody MAC 387, calprotectin was found to be expressed in oral keratinocytes from normal, non-inflamed oral mucosa. Orthokeratinized sites including the attached gingiva and hard palate expressed low levels of calprotectin with a restricted pattern; immunoreactants were identified only within subcorneal keratinocytes. Parakeratinized mucosa from the lips, soft palate, tongue and buccal mucosa expressed calprotectin in a more widespread, yet variable pattern, immunoreactants being detectable in only a portion of the spinous layer in some cases whereas in others the pattern of expression was more topographically diffuse. Antigen was not detected in basilar and lower strata cells. Both cytoplasmic and nuclear decoration could be identified. The results indicate that oral mucosa harbours an antimicrobial deterrent to micro-organisms that may enhance the physical epithelial barrier of host defence.

Polymerase chain reaction: relevance for oral pathology

The polymerase chain reaction (PCR) is a recent innovation in biotechnology for amplifying specific nucleic acid sequences by use of repeated cycles of DNA synthesis. Application of PCR has been extended to a wide variety of biological and medical disciplines; fields of application include molecular genetics, pathology, microbiology, forensic medicine, and infectious diseases. Because of its speed and powerful sensitivity, PCR has become a highly valuable method for detecting small amounts of target nucleic acid sequence with the caveat that it has certain limitations. Importantly, false-positive reactions can result from the amplification of contaminating DNA whereas false-negative reactions can result from introduction of inadequate numbers of primer sequences. The application of PCR in the context of oral pathology is presented along with a discussion of the utility of this technique to aid in the elucidation of the etiology of oral disease.

Viral infections of the head and neck among HIV-seropositive patients

Many viruses cause opportunistic infections in HIV-positive patients. Those that cause oral lesions include herpes simplex, varicella zoster, Epstein-Barr virus, cytomegalovirus, and papillomavirus. Importantly, many of the herpes-group viruses are able to augment immunosuppression and some actually transactivate HIV replication-inducing genetic sequences. This article reviews the role of viral agents in the activation of HIV replication and details the features of the reported oral lesions that represent viral opportunistic infections.

Detection of human papillomavirus-genomic DNA in oral epithelial dysplasias, oral smokeless tobacco-associated leukoplakias, and epithelial malignancies

Human papillomavirus (HPV) is an infectious agent that is increasingly associated with mucosal cancers, in particular cancer of the cervix. The present investigation was undertaken in an attempt to determine whether HPV could be easily detected in biopsies of oral tissues, specifically oral squamous cell carcinomas, oral epithelial dysplasias, smokeless tobacco keratoses, verrucous hyperplasia, and verrucous carcinoma. In situ DNA hybridization methods were used to isolate specific HPV genomes. Among 100 instances of benign leukoplakia, only 4% of non-tobacco-related and 10% of smokeless tobacco-related lesions harbored viral sequences. We were able to detect viral sequences in dysplastic lesions 3% of the time. Alternatively, 17% and 20% of the verrucous hyperplasias and verrucous carcinomas were positive for viral nucleic acids. Six percent of the squamous cell carcinomas harbored HPV. On the basis of these findings, it is concluded that HPV of known genotype can be identified in oral premalignant and malignant neoplasms.

Comparison of clinical characteristics in myogenic, TMJ internal derangement and atypical facial pain patients

Temporomandibular joint (TMJ) disorders have been collectively grouped as myofascial pain-dysfunction syndrome (MPDS) or temporomandibular joint dysfunction syndrome (TMJDS). In the past, these terms have been used synonomously to describe a set of clinical signs and symptoms that include pain in the TMJ and muscles of mastication, limited or deviant opening of the mandible, and/or joint sounds. The present study segregated two major subgroups subsumed within this diagnostic classification and assigned them to a myogenic facial pain (MFP) group and a TMJ internal derangement (TMJID) group. Previous studies may have included both of these disorders as MPDS/TMJDS. While some signs and symptoms are similar, the primary differentiation is based on meniscus displacement present with TMJID patients and pain distribution patterns between the two groups. While MFP/TMJID patients comprise the majority of the facial pain population, a third major group of patients is encountered, being classified under the diagnostic appellation of atypical facial pain (AFP). Patients with AFP usually complain of vague and wandering pain in the maxilla or mandible; however, no identifiable source of infection or organic disease can be uncovered. One hundred fifty patients seeking consultation and care for facial pain met the criteria for inclusion into one of three clinical groups. The groups were compared for age, sex, duration of symptoms, bruxism and/or clenching habits, and disturbed sleep patterns. Differences in surface electromyographic levels from the facial and cervical muscles were also examined. Minnesota Multiphasic Personality Inventory (MMPI) scores from 95 subjects were compared with self-report measures of depression and anxiety. It was concluded that subcategorization of myofascial pain dysfunction patients into a MFP and TMJID group is justified on the basis of psychometric differences, clenching habits, masseter EMG levels, and male:female ratio. Furthermore, psychopathological factors are more significant among MFP and AFP subjects than TMJID patients.