Search PubMed⌕ Search

Biomedical subjects

D R Weathers

Publications and source records attributed to D R Weathers.

At least 19 recordsLinked to original sources
PubMed1997

Distinguishing features of focal cemento-osseous dysplasia and cemento-ossifying fibromas. II. A clinical and radiologic spectrum of 316 cases.

The distinguishing histopathologic features of focal cemento-osseous dysplasia (FCOD) (including lesions occurring in both anterior and posterior jaws) and cemento-ossifying fibroma (COF) (ossifying fibroma and cementifying fibroma) were demonstrated in our earlier work. The aim of the current study was to further refine their clinical and radiographic features. We have assessed 18 clinical and radiographic parameters by univariate comparisons (chi-squared and Student t tests), and a multivariate assessment (logistic regression) in 241 cases of FCOD and 75 of COF. These cases were diagnosed from a combination of clinical, radiographic, and histopathologic information. FCOD was seen predominantly in black women, with a peak incidence in the fourth and fifth decades, whereas COF showed no female predilection except in the fourth decade (p < 0.005). COF occurred in patients an average of 10 years younger than patients with FCOD (p < 0.0001). Most patients with FCOD were asymptomatic (62%); the average lesion size was 1.8 cm. More than half of patients with COF displayed jaw expansion and a considerably larger size lesion (mean 3.8 cm, p < 0.001). The mandible was the most frequent site for both FCOD (86%) and COF (70%). Radiographically, a well-defined border was observed in 53% of cases of FCOD and 85% of cases of COF (p < 0.01). Cases of FCOD mostly demonstrated an irregularly mixed radio-opacity (69%), whereas 53% of COFs presented as a radiolucency (p < 0.005). In FCOD, there was a close association with tooth apices (70.6%, p < 0.0001) or with previous extraction sites (21%, p < 0.05); however, the majority of COF cases (86%) showed no relationship with either. Combining the radiographic feature of a periapical location with the pathology of multiple curetted fragments and "ginger root" bony trabeculae, allowed 90% sensitivity and 89% specificity in a logistic regression model to predict the lesion to be an FCOD. These findings provide guidelines not only to distinguish these two entities clinically, but also aid in reaching an accurate diagnosis histopathologically.

Adolescent↗
PubMed1997

Distinguishing features of focal cemento-osseous dysplasias and cemento-ossifying fibromas: I. A pathologic spectrum of 316 cases.

Focally expressed cemento-osseous dysplasia (periapical cemento-osseous dysplasia and focal cemento-osseous dysplasia) and cemento-ossifying fibroma (ossifying fibroma and cementifying fibroma) are two clinically recognized entities that are not easily differentiated histopathologically because of the lack of recognition of specific microscopic features. We have assessed 20 pathologic parameters for their ability to distinguish reliably between the two. Included in this study were 241 cases of focally expressed cemento-osseous dysplasia and 75 cases of cemento-osseous fibroma diagnosed from a combination of clinical, radiographic, and histopathologic information. Results revealed that 92.5% of focally expressed cemento-osseous dysplasia were composed of multiple small fragments of tissue whereas 88.0% of cemento-osseous fibromas showed a large intact specimen. Thick curvilinear trabeculae ("ginger root" pattern) or irregularly shaped cementum-like masses were typically seen in focally expressed cemento-osseous dysplasia, whereas thin isolated trabeculae with prominent osteoblastic rimming were more commonly observed in cemento-osseous fibroma. The stroma of focally expressed cemento-osseous dysplasia often displayed characteristic cavernous-like vascularity that was almost always associated with bony trabeculae. Free hemorrhage was frequently interspersed in the artifactual spaces throughout focally expressed cemento-osseous dysplasia. In contrast, the cases of cemento-osseous fibroma showed more cellularity in the stroma in which a storiform pattern was present in more than half the lesions studied. Giant cells, when present in cemento-osseous fibroma, were clustered in the center of the cellular stroma. The features described here allowed distinction histopathologically in 94% of cases studied. Three progressive stages of focally expressed cemento-osseous dysplasia and subtypes of cemento-osseous fibroma may be recognizable microscopically.

Blood Vessels↗
PubMed1997

A chemical treatment regimen to reduce bacterial contamination in dental waterlines.

This article describes a pilot study in which the authors used aerobic bacterial cultures to compare the effects of 1:10 mouthwash, 1:20 mouthwash and 2 percent ethanol in reservoir systems with seven conventional water systems. The long-term, low-concentration antiseptic reduced bacteria to within acceptable limits.

Anti-Infective Agents, Local↗
PubMed1994

Necrosis in benign salivary gland neoplasms. Not necessarily a sign of malignant transformation.

Necrosis that occurs in a salivary gland neoplasm is usually considered to be an ominous sign, suggesting malignant transformation, particularly in lesions that have had no prior manipulation such as fine-needle aspiration. We describe five pleomorphic adenomas and two canalicular adenomas of salivary gland origin that exhibited necrosis, yet were otherwise benign. All lesions displayed a distinctive histopathologic pattern characterized by a narrow rim of viable tumor tissue at the periphery of the neoplasm combined with a diffuse central region that demonstrated apparent ischemic necrosis. No invasion of adjacent normal tissue was identified, and no recurrence or metastasis has been seen with these lesions. Caution should be exercised in the evaluation of salivary gland neoplasms with central necrosis to avoid misdiagnosis of all such lesions as malignant.

Adenoma↗
PubMed1992

Merkel cell carcinoma of the labial mucosa. An immunohistochemical and ultrastructural study with a review of the literature on oral Merkel cell carcinomas.

Merkel cell carcinoma is a rare cutaneous neuroendocrine tumor that occurs predominantly in the head and neck region of older patients. An 88-year-old white man had an erythematous, umbilicated tumor on his lower lip, which on histopathologic examination showed solid sheets of infiltrating basaloid round cells with a high mitotic index. Globular, paranuclear immunostaining for low-molecular-weight cytokeratins (Nos. 8, 18, and 19) and neurofilament was observed. On ultrastructural examination, the tumor cells demonstrated paranuclear whorls of intermediate filament aggregates and occasional electron-dense granules. This unique cytokeratin- and neurofilament-staining pattern with coexpression enabled the Merkel cell carcinoma to be differentiated from other small cell malignant tumors that included metastatic neuroendocrine carcinomas from other regions. The follow-up 1 year after surgery and radiation showed that the patient remained disease free. Review of the literature revealed 11 cases of oral Merkel cell carcinomas with a predilection for the labial mucosa of older men. The mode of treatment and the clinical course of these cases are also presented, with an update on therapeutic management of Merkel cell carcinomas.

Aged↗
PubMed1988

Inhibition of E rosetting and of OKT 11 in patients with oral dysplasia and neoplasia.

A group of patients with oral dysplastic or early neoplastic lesions has been followed for 6 years to examine the change in ALS (antilymphocyte serum) induced 25% E rosette inhibition during the course of their disease. Control patients with other oral problems were examined similarly. The E rosette inhibition titer differences seen in our previous studies between control and diseased patients do not appear to persist with a longitudinal examination of these patients. While at early examination the patients exhibit higher inhibition titers than controls, later analysis shows that they seem to return to normal. To improve methodology, inhibition of OKT 11 uptake was substituted for E rosette inhibition and it is clear that both methods measure the same phenomenon. Thus, the former is more accurate and quantitative than the latter and will be used in future work. Continuation of these studies with the examination of more patients will be of value in assessing possible T lymphocyte changes in patients with oral lesions.

Antigens, Surface↗
PubMed1987

Intravascular fasciitis: a case report of an intraoral location.

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.

Adult↗
PubMed1985

Effects of smokeless tobacco on the periodontal, mucosal and caries status of adolescent males.

The use of smokeless tobacco (ST) products, such as snuff and chewing tobacco, was investigated in a school population of 565 males with a mean age of 13.8 years. All students completed a tobacco usage questionnaire and were given intraoral examinations by a team of dentists to determine the possible relationship of ST usage to the presence of gingivitis, gingival recession, mucosal pathology and caries. The overall prevalence of ST usage was 13.3%, which was much higher than the 1.4% prevalence of cigarette smoking. Pairwise chi square analysis revealed that there was no relationship between ST usage and the prevalence of gingivitis, but that the prevalence of gingival recession was significantly elevated in ST users, P less than 0.001. The odds of having gingival recession were 9 times greater in the students using smokeless tobacco as compared to healthy, non-user cohorts. ST usage did not affect the prevalence of gingival recession in students without gingivitis. The frequency of occurrence of soft tissue pathology was significantly elevated, about 6-fold in students who used smokeless tobacco, as compared to non-users, P less than 0.01. This was principally due to the increased prevalence of white mucosal lesions in smokeless tobacco users. However, there was no attributable risk for mucosal pathology in ST users who were free of gingivitis. Similarly, the use of smokeless tobacco was associated with a 1.6-fold elevation in mean DMF in students with gingivitis, P less than 0.001, but this increase in caries experience was not seen in ST users who were free of gingivitis. In summary, in students with clean mouths that were free of gingivitis, the use of smokeless tobacco was not associated with a change in the prevalence of gingival recession, mucosal pathology, or in the mean DMF score. In contrast, smokeless tobacco usage was a significant risk factor in individuals with co-existing gingivitis, associated with a marked increase in the prevalence of gingival recession, mucosal pathology and caries experience.

Adolescent↗
PubMed1985

Characterization of two types of crystalloids in pleomorphic adenomas of minor salivary glands. A light-microscopic, electron-microscopic, and histochemical study.

Crystalloids have been previously described in salivary gland tumors. In order to ascertain the incidence of these structures, the authors reviewed a series of 294 minor salivary gland tumors. One hundred thirty pleomorphic adenomas were identified, and 6 of these contained crystalloids. No crystalloids were found in other benign or malignant salivary gland tumors. These six file cases and a recent seventh case containing crystalloids were studied by light and electron microscopy and with histochemistry. Two types of crystalloids were found. One case contained previously described tyrosine-rich crystalloids, and the other six contained crystalloids composed of radially arranged collagen fibers. Both types of crystalloids are further characterized and discussed.

Adenoma, Pleomorphic↗
PubMed1983

Intraoral multifocal adult rhabdomyoma. Report of a case and review of the literature.

Adult rhabdomyomas are uncommon, benign neoplasms of the head and neck region. They are usually solitary, but may rarely be multifocal. We report the clinical and morphologic features of a multifocal adult rhabdomyoma apparently present in the floor of the mouth of an elderly woman for 20 years. At the time of exploratory surgery, the surgeon believed there was diffuse multinodular enlargement of both sublingual glands. The differential diagnosis of a biopsy specimen that was taken for frozen section included salivary gland oncocytosis, a reactive process. On examination of permanent sections, however, the lesion was found to be a multifocal rhabdomyoma. No evidence of salivary gland tissue was found. Ultrastructural study demonstrated the characteristic attempts by this tumor to recapitulate its origin from skeletal muscle by the formation of abnormal contractile elements.

Aged↗
PubMed1981

Reactivation of Hand-Schüller-Christian disease six and thirteen years after discontinuation of systemic therapy.

We present two cases of reactivation of Hand-Schüller-Christian disease or multifocal eosinophilic granuloma 6 and 13 years after discontinuation of systemic therapy. Both patients received oral therapy with methotrexate and prednisone continuing for 2--3 years after the disease was thought to be in remission. Relapses were detected because of disease symptoms and treated with surgery with or without radiation. Neither patient has required reinstitution of systemic therapy. These cases are cited as evidence of the chronicity of the disorder and as a reminder that reactivation is possible after years of disease inactivity. Therefore, long-term clinical follow-up of patients in remission is indicated.

Child, Preschool↗
PubMed1981

Aggressive fibromatosis involving the paramandibular soft tissues. A study with the aid of electron microscopy.

The distinction at the level of light microscopy between aggressive fibromatosis and low-grade malignancies with fibroblastic features may be difficult. An electron microscopic study of four cases of aggressive fibromatosis of the mandibular soft tissue was undertaken to determine whether any ultrastructural characteristics could be identified that would aid in a more uniform distinction between these lesions. The pertinent findings include the identification of cells of fibroblastic derivation showing a range of organelle-poor to organelle-rich features, cytoplasmic microfibrils, and dilated rough endoplasmic reticulum profiles. These features are discussed in the light of previously published findings of other forms of aggressive fibromatosis and closely related lesions. The study reaffirms that although electron microscopy may be useful in confirming the cell of origin in these lesions, the accurate diagnosis of fibrous tumors still rests with the proper correlation of clinical and light microscopic features. Clinical follow-up of the cases supports both the diagnosis of aggressive fibromatosis and the recommended treatment of adequate local excision.

Adolescent↗
PubMed1981

Relationship of vitamin A intake and E rosette inhibition to oral dysplasia and neoplasia.

The present study investigated the 25% E rosette inhibition titer and vitamin A intake levels of patients with dysplastic or neoplastic lesions of the oral cavity as compared to control subjects with or without a variety of other oral diseases. All subjects were followed with repeat examinations beginning at the time of entry in the study and approximately every 6 months thereafter. E rosette inhibition titers generally increased as the lesions became more dysplastic. In the control group titers remained at a low level throughout the study. Vitamin A intake levels were mostly below one-half or above twice the recommended daily allowance in patients with dysplasias and in a few controls with nondysplastic oral disease. Some patients with dysplasias were in the normal range. The results of vitamin A measurements were compatible with a variety of studies suggesting a role for vitamin A in the genesis of epithelial dysplasias. The pattern of observed E rosette inhibition titers was in keeping with previous work in our laboratory as well with that of others who described a correlation between the height of titers and the degree of dysplasia.

Adult↗
PubMed1980

Verruciform xanthoma.

Twenty-one cases of verruciform xanthoma are reported, bringing to fifty the total cases in the literature. The lesion was found most often in middle-aged persons, and the most common location was the gingiva or alveolar ridge. The cause of the verruciform xanthoma is still uncertain.

Adolescent↗