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.

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.

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.

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.

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.

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.

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.

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.