Squamous odontogenic tumor.

Squamous odontogenic tumors are rare benign neoplasms of the jaws that are thought to originate from remnants of the dental lamina. They have been confused with other lesions composes of nests of squamous epithelium including well-differentiated squamous carcinoma. The clinicopathologic features of two squamous odontogenic tumors are presented. The electron-microscopic appearance of one of these is described, and the 16 previously reported cases are reviewed.

Characterization of immunocompetent cells in the diseased canine periodontium.

The beagle dog with naturally occurring periodontal disease is one of the most widely used animal models in periodontal research for histological studies on disease pathogenesis and on the effect of potential therapeutic regimens. However, previous studies were restricted to morphological assessment of immunocompetent cells because of the lack of available cell-specific markers. In this study we systematically characterized the specificity and immunoreactivity of a panel of anti-human antibodies for identification (ABC method) of immunocompetent cells in formalin-fixed, EDTA-decalcified, paraffin-embedded inflamed periodontal tissues obtained from six beagle dogs. Canine lymph nodes and a panel of different human tissues served as positive controls. Polyclonal anti-CD3 immunolabeled canine T-lymphocytes specifically. Anti-CD79alpha (clone HM57) reacted with B-lymphocytes and plasma cells, and CD79alpha (clone JCP117) showed no staining in canine tissues. Neutrophils, monocytes, small macrophages, and keratinocytes reacted with an anti-myeloid/histiocyte antibody (clone MAC387). Anti-CD68 (clones PG-M1 and EBM11) immunolabeled large macrophages and plasma cells. Clone EBM11 also stained osteoclasts and cementoclasts. With the exception of JCB117, all antibodies revealed similarly favorable immunolabeling of canine and human immunocompetent cells. Long-term EDTA decalcification appeared to weaken immunostaining of plasma cells with HM57. MAC387 and CD68 can be used to distinguish macrophages in different differentiation stages in canine periodontal tissues. (J Histochem Cytochem 46:1443-1454, 1998)

Detection and characterization of interleukin-1 in human dental pulps.

Pulp tissue was obtained from clinically intact third molars and premolars, and from teeth affected by caries and periodontal disease. After incubation and homogenization, supernatants were centrifuged, sampled and assayed for lymphocyte activating factor-like activity using the thymidine-incorporated D10.G4.1 cell-line assay. Significantly higher levels of mitogenic activity were found in the pulp supernatants of symptomatic carious teeth, and in those of third molars with attendant pericoronitis, than in pulps from symptomatic and asymptomatic periodontally affected teeth and asymptomatic third molars and premolars. As both interleukin-1 (IL-1) and interleukin-2 (IL-2) may be involved in the proliferation of D10.G4.1 cells, supernatants from carious pulps were further tested for IL-2 activity using murine natural killer (NK) cells. Those that had elicited a proliferative response of D10.G4.1 cells did not enhance NK proliferation, indicating that the factor responsible for clonal replication of D10.G4.1 cells was IL-1. To confirm the presence of IL-1, immunohistochemistry using a monoclonal antibody to IL-1 was performed on frozen and paraffin-embedded sections of pulps from each group. IL-1 was immunolocalized within cells in pulps from the caries symptomatic group. The cell type producing IL-1 was further characterized as an alpha-naphthyl-acetate-esterase-positive macrophage within the connective tissue stroma of pulps from the caries symptomatic group. This novel demonstration of IL-1 and IL-1 producing cells in human dental pulp indicates the involvement of this mediator of inflammation in dental disease.

The 'fixed' removable partial denture: report of case.

Careful monitoring of tissue that had been the site of three previous surgical procedures was necessary, but the patient needed a functional, esthetically acceptable prosthesis. The Andrews bridge was selected because it combines the stabilizing qualities of a fixed prosthesis with the accessibility to the tissues of a removable prosthesis. The recurring nature of the verrucous carcinoma along with extensive tissue loss were additional factors in selecting this appliance. The final results satisfied all the criteria. The patient has been seen at regular follow-up visits for 2 years since the last surgical procedure and there has been no clinical change in the previously involved tissue. The patient has tolerated the prosthesis well and is satisfied with her appearance.

Warty dyskeratoma of the oral mucosa. Correlated light and electron microscopic study.

A warty dyskeratoma arising from the palatal mucosa of a 36-year-old man was studied by light and electron microscopy. The ultrastructural features of this lesion were compared with those of the lesions of Darier's disease. Histologic sections showed a keratin-filled depression of the epithelial surface, suprabasal clefting, and acantholytic, dyskeratotic grains and corps ronds. Electron microscopic examination revealed a decrease in the number of intact attachment sites on the surfaces of the epithelial cells adjacent to the suprabasal cleft. Acantholytic grains within the cleft contained dense bands of tonofilaments and were devoid of attachment sites. Corps ronds within the stratum granulosum appeared as dyskeratotic vacuolated cells. Warty dyskeratomas and the lesions of Darier's disease are clinically distinct, but the acantholytic and dyskeratotic cells characteristic of both show many ultrastructural similarities.

Parosteal osteosarcoma of the maxilla.

Parosteal osteosarcoma is a low-grade form of osteosarcoma that rarely affects the jaws. A case involving the maxilla of a 25-year-old man is presented, and four previously reported cases are reviewed.

Intraoral spindle cell lipoma: case report with correlated light and electron microscopy.

A nontender submucosal nodule in the anterior floor of the mouth of a 33-year-old woman was removed surgically. Light and electron microscopic studies revealed features of a spindle cell lipoma, i.e., a well-circumscribed, unencapsulated mass composed of a mixture of univacuolated lipocytes and fibroblast-like spindle cells within a mucinous and collagenous stroma. To our knowledge this is the first reported case of a spindle cell lipoma in the oral cavity.

Myospherulosis of the oral hard and soft tissues.

Myospherulosis is a unique, inflammatory, granulomatous lesion, which results from the action of lipid substances on extravasated erythrocytes. Petrolatum-based antibiotic ointments are the most frequent etiologic agents of iatrogenically acquired lesions. Six intraoral cases of myospherulosis are presented, including the first reported case in oral soft tissues. The literature of reported cases is summarized and the epidemiology, histopathology, and ultrastructure of the lesions are discussed. Predisposing events and recommendations for future use of petrolatum-based antibiotic ointments are presented.

Heterotopic gastrointestinal cyst of the tongue.

A 6.5-month-old white male presented with a cyst involving the left posterior half of his tongue which partially compromised his airway. A computed tomography scan revealed that the mass also involved the left floor of the mouth. Surgical excision of the mass was performed, and the mass was demonstrated to be a gastrointestinal heterotopic cyst. The clinical and pathological features of this rare lesion are presented and the pathogenesis is discussed.

Growth of intestinal neomucosa on prosthetic materials.

The short bowel syndrome is a potential complication of the surgical management of diseases of the large and small intestine. Recently methods have been examined for expanding the small bowel absorptive area using prosthetic materials. We investigated the feasibility of growing intestinal mucosa on prosthetic patches and tubes. Ileal defects were patched with a 2 X 5-cm patch of either Dacron (n = 15), polyglycolic acid mesh (PGA) (n = 9), or polytetrafluroethylene (PTFE) (n = 5) prosthesis in New Zealand white male rabbits. Gross and microscopic analysis at 2, 4, and 8 weeks revealed that the serosal surface was covered with neomucosa by 4 weeks. Dacron and PTFE grafts were either minimally attached or extruded and PGA grafts had dissolved. At 8 weeks, none of the patches were present but with all three materials the resultant area of neomucosa was only 15% of the original defect. The neomucosa was functional as determined by glucose uptake and disaccharidase activity. Three centimeter Dacron tubes were interposed in the distal ileum of 10 rabbits and in a bypassed ileal segment in 11 rabbits. There was an 80% mortality within 2 weeks, and no evidence of neomucosal growth. Although prosthetic patches support the growth of functional neomucosa, there is a minimal increase in the final surface area. The type of prosthesis did not influence the outcome. The use of Dacron tubes is associated with high mortality and no neomucosal growth. The use of prosthetic materials is not likely to be useful in the clinical management of the short bowel syndrome.