Binge drinking among college students: a comparison of California with other states

The aim of the present study was to describe the expression and distribution of bone morphogenetic protein (BMP) in odontogenic tumors by immunohistochemistry using monoclonal antibody against bovine BMP (BMPMcAb). Eight types of odontogenic tumors (44 cases), including ameloblastoma (20 cases), cementifying fibroma (8 cases), benign cementoblastoma (5 cases), dentinoma (3 cases), compound odontoma (2 cases), adenomatoid odontogenic tumor (2 cases), calcifying epithelial odontogenic tumor (2 cases) and odontogenic fibroma (2 cases), were studied. The results showed that, according to the immunostaining pattern of BMPMcAb, tumors could be classified into two types: all cementifying fibromas, benign cementoblastomas, dentinomas, odontogenic fibromas, and compound odontomas demonstrated a positive reaction, whereas all ameloblastomas, adenomatoid odontogenic tumors, and calcifying epithelial odontogenic tumors were negative. BMPMcAb-positive odontogenic tumors were those tumors with formation of enamel, dentin, cementum or bone. Therefore, BMP might play an important role in the formation of calcified dental tissues and the development of odontogenic tumors contaning such tissues.     

Ameloblastic fibro-odontoma: report of two cases

Ameloblastic fibro-odontoma is a rare odontogenic tumour. It affects young people and is usually located in the posterior jaws. Two cases of this tumour are presented: both lesions had produced an asymptomatic swelling. The histology showed the presence of an odontogenic epithelium immersed in a fibrous mesenchyme; dental hard tissues were also present. No recurrences were found after 12 and 4 years from the surgical enucleation of the tumour.     

The new-generation laser surgical apparatus Doktor in the combined treatment of stomatological disease in an outpatient setting

Presents the design, technological characteristics (wavelength 10.6 mu cm, power up to 7 W, permanent mode) of a new-generation surgical laser Doktor and its use in the treatment of dental and maxillofacial diseases (diseases of the periodontium and buccal mucosa, pericoronitis, trophic ulcers, retention cysts, furuncles and carbuncles of the skin of the neck and face, odontogenic inflammatory processes, injuries, tumors) and in reconstructive, plastic, and cosmetologic surgery.     

Odontogenic epithelium induces similar molecular responses in chick and mouse mandibular mesenchyme

Previous observations have shown that, during the initiation phase of odontogenesis, signals from mouse odontogenic epithelium can elicit teeth in non-odontogenic but neural crest-derived mesenchyme isolated from ectopic sites including chick mandibular mesenchyme. In the present study the formation of ectopic tooth buds and dental mesenchyme in chick mandibular mesenchyme was examined using heterospecific recombinations between E11 mouse odontogenic epithelium and stage 23 chick lateral mandibular mesenchyme. Both morphological criteria and chick-specific probes for Msx-1, Msx-2, and Bmp-4 mRNAs were used as markers for early dental mesenchyme. Our results demonstrated that interactions of mouse odontogenic epithelium with chick mandibular mesenchyme induce early changes in the chick mandibular mesenchyme including the appearance of a translucent zone, cell proliferation, and induction of expression of Msx-1, Msx-2, and Bmp-4, which have been shown to be associated with the formation of dental mesenchyme. In addition, tooth bud-like structures that resemble E13 tooth buds in vivo both morphologically and in their patterns of gene expression formed after 6 days in the heterospecific recombinations. The tooth bud-like structures consist of invaginated mouse mandibular epithelium and condensed chick mandibular mesenchyme expressing high levels of Msx-1 and Bmp-4, but undetectable levels of Msx-2. Unlike the induction of Msx-1, Msx-2, and Bmp-4 in the underlying mesenchyme, which is specific for signals derived from odontogenic epithelium, the induction of a translucent zone and cellular proliferation in the underlying mesenchyme may be related to the growth-promoting potential of embryonic epithelia and not be specific to signals derived from the odontogenic epithelium. Similar to mouse odontogenic epithelium, agarose beads soaked in recombinant BMP-4 induced a translucent zone, cellular proliferation, and expression of Msx-1, Msx-2, and Bmp-4 in chick mandibular mesenchyme after 24 hours. These observations together showed that avian mandibular mesenchyme has odontogenic potential that is expressed upon interactions with inductive signals from mouse odontogenic epithelium. Similar to odontogenesis in vivo, formation of dental mesenchyme in chick mandibular mesenchyme is mediated by the activation of Msx-1, Msx-2, and Bmp-4.     

Odontogenic fibroma in Sprague-Dawley rats: a report of 2 cases

Two cases of odontogenic fibroma occurring in aged Sprague-Dawley rats are described. Both neoplasms were associated with a maxillary incisor and had identical histomorphological features. They were composed of solid proliferations of primitive, dental pulp-like mesenchyme separated by areas of collagenization. Small strands and islands of mainly undifferentiated odontogenic epithelium immunostaining for keratins were scattered throughout both tumours. As a further characteristic, the lesions contained small foci of mineralization which were either cementum-like or resembled dysplastic dentin. The odontogenic fibroma represents a further type of odontogenic tumour in rats, which due to its typical histomorphology, can easily be differentiated from other odontogenic tumours such as ameloblastic odontoma or ameloblastoma.     

A survey of epithelial odontogenic tumors and cysts in dogs and cats

A retrospective histologic study of 12 canine and eight feline epithelial odontogenic tumors and cysts was conducted from oral masses (n = 3,917) obtained between 1980 and 1990. No sex or breed predilection was identified. Ameloblastoma was observed in two dogs (case Nos. 1, 2) 6 and 8 months of age. Calcifying epithelial odontogenic tumors were seen in a dog (case No. 3) and in two cats (case Nos. 4, 5) between 8 and 16 years of age. Ameloblastic fibroma (or fibroameloblastoma) was observed in cats (case Nos. 6-10) only. Inductive fibroameloblastoma was observed in four cats (case Nos. 6-9) up to 1 year of age, whereas ameloblastic fibroma was seen in a 14-year-old cat (case No. 10). A single ameloblastic odontoma was identified in a 20-month-old dog (case No. 11). Two complex odontomas occurred in a 6-month-old (case No. 12) and a 4-year-old (case No. 13) dog. Odontogenic cysts were identified in five dogs (case Nos. 14-18) aged 4.5 months to 16 years and in a 1-year-old cat (case No. 19) and have not been previously reported in these species. These cysts were lined by a stratified epithelium reminiscent of the appearance of ameloblastic epithelium. An odontogenic keratocyst with prominent central parakeratotic keratinization was identified in one 9-year-old female dog (case No. 20). Almost all epithelial odontogenic tumors were circumscribed, benign tumors that warranted a good prognosis for survival, although local recurrence may have followed (or may follow) incomplete excision. Calcifying epithelial odontogenic tumors may be locally invasive. Of six odontogenic cysts (case Nos. 14-19), two (case Nos. 15, 18) gave rise to basi-squamous carcinomas. The classification and behavior of epithelial odontogenic tumors and cysts in human beings, dogs, and cats are discussed.     

The maxillary sinus and odontogenic cysts

An unilateral maxillary sinusitis is frequently caused by dental pathology. An odontogenic cyst in the maxillary sinus usually lacks accompanying symptoms of infection. In three patients, a 35-year-old man and two women aged 16 and 28, an odontogenic cyst in the maxillary sinus was diagnosed. Consultation of a maxillofacial surgeon is needed because orthopantomographic imaging is diagnostically most helpful. In these patients combined treatment by an ENT surgeon and a maxillofacial surgeon is important.     

Cutaneous odontogenic sinus tract to the chin: a case report

We report a case of cutaneous odontogenic sinus tract to the chin. The patient first noticed the cutaneous condition in 1977. Inappropriate medical and dental treatment was ineffective. Correct diagnosis and treatment was completed in 1993. We offer diagnostic and treatment guidelines for the management of similar cases.     

Compound odontoma in a dog

Compound odontomas are rare tumors of dental origin. Though benign, their effect as a space occupying lesion can be dramatic. A large compound odontoma in the caudal right mandible of a five and a half month old dog was managed by surgical enucleation of the abnormal tissues. No recurrence was evident 6 months later.     

Clinical evaluation of pulsed ND:YAG dental laser applied on oral soft tissues

This investigation was conducted to evaluate the pulsed Nd: YAG dental laser, as a surgical tool for many of the oral surgical procedures. Gingivoplasty, minor gingivectomy, operculectomy excision of pedunculated tumors, frenectomy, incision and drainage of oral abscesses, control of oral bleeding and many other procedures were included in the study. The results presented here suggest that the pulsed Nd: YAG laser can be used to cut efficiently through vascular tissues, necrotic tissues and thin pedunculated masses. So it could be considered selective but not conclusive in surgery of the oral soft tissues.     

Immature teratoma of the ovary with a neural component ("solid" teratoma). A clinicopathologic study of 20 cases

Twenty cases of immature teratoma of the ovary with a neural component are analyzed. A plea is made for use of the nomenclature adopted from the new World Health Organization classification of ovarian tumors, the past confusion over terminology and histogenesis of this rare tumor is discussed. All the primary tumors in the present series contained at least some immature tissues (predominantly of neural origin) and were thus graded from 1 to 3 according to the criteria of Thurlbeck and Scully. No grade 0 tumors ("benign solid teratomas") were identified. We believe that thorough sectioning almost always insures the identification of immature elements. The prognosis was closely related to the histologic grade, but correlated poorly withthe clinical stage, the latter being influenced by the common finding (25 per cent of the cases in this series) of peritoneal implants composed exclusively of mature glial tissue, which is associated with a benign clinical evolution. This phenomenon of maturation or differentiation appears to be the rule rather than the exception in this tumor, since implants are usually of better or equal differentiation when compared with their primary tumors and older patients tend to have lower grade tumors than younger patients. Since the majority of patients with this tumor are young, primary surgical therapy should be conservative, unilateral salpingooophorectomy often being sufficient. Spontaneous or operative rupture of the tumor capsule carries an increased risk of subsequent dissemination. We have noted impressive clinical responses in patients with disseminated tumors of a high histologic grade after treatment with triple chemotherapy (vincristine, actinomycin D, and cyclophosphamide) but do not recommend adjuvant therapy in patients with only grade 0 implants.     

Clear cell odontogenic carcinoma with lymph node metastasis

Clear cell odontogenic tumors are rare. Review of the literature showed 9 cases with a prominent clear cell component. These lesions have exhibited an aggressive behavior characterized by an infiltrative local growth pattern, recurrence, or metastases. We report a case of an odontogenic tumor that exhibited a biphasic pattern and was characterized by lymph node involvement identical histologically to the primary tumor. We conclude that the presence of a clear cell component in an ameloblastomatous tumor should be viewed as a sign of de-differentiation, and that a malignancy with or without metastases should be considered and ruled out in such cases.     

Morphological changes of epithelial rests of Malassez in rat molars induced by local administration of N-methylnitrosourea

The objective was to examine the possibility that epithelial rests of Malassez can give origin to odontogenic tumours. A mixture of N-methylnitrosourea (MNU) and alginate impression material for dental use was injected onto the periosteum of the buccal side of the left mandible of 5-week-old, male Wistar rats (300 mg/kg body wt). The mixture was left at the site for several months. The rats were killed 1, 3, 5, and 8 months after the injection. After 5 and 8 months, the epithelial rests of Malassez in the cervical and bifurcational regions of the first, second, and third left mandibular molars were significantly enlarged and the alveolar bone around the lesion was resorbed by multinucleated cells in all rats. The epithelial masses were characterized by enamel organ-like structures, deposition of eosinophilic amorphous material, duct-like structures, and squamous metaplasia. In addition to these masses in the molar regions, odontogenic tumours were induced in the incisal region and carcinomas and sarcomas in the buccal region, knee, bladder, and skin. Local administration of a mixture of MNU and alginate impression material can induce odontogenic tumours from the epithelial rests of Malassez at high incidence.     

Morphologic analysis of odontogenic cysts with computed tomography

PURPOSE: The purpose of this study was to analyze the effects of lesion site and epithelial keratinization on the morphologic characteristics of odontogenic cysts and clarify determinate factors for cyst morphology. MATERIAL AND METHODS: Computed tomographic images of 92 odontogenic cysts were analyzed: 31 primordial, 31 dentigerous and 30 radicular. Thirty-four cysts were located in the maxilla (6 primordial, 10 dentigerous, and 18 radicular) and 58 in the mandible (25 primordial, 21 dentigerous, and 12 radicular). Histologically, 31 cysts showed epithelial keratinization (18 primordial and 13 dentigerous). No keratinization was seen in radicular cysts. The morphologic features of cysts were assessed by measuring long length parallel to dental arch and short length vertical to it and calculating the long/short ratio. In addition, the computed tomography pattern of the cyst was classified into unilocular, lobulated, and multilocular patterns. Appearance of the sclerotic rim and surrounding cortex were classified into three and four patterns respectively to evaluate the developmental features of the cyst. RESULTS: As a whole, the long length of the primordial cysts was statistically larger than the other two cyst groups and resulted in a larger long/short ratio. Statistical differences of CT pattern were also seen among cyst groups. There was no preference in any cyst group for the appearance of the sclerotic rim and cortex. There were statistical differences between maxilla and mandible in short axis and long/short ratio. The maxillary cysts generally showed round shapes irrespective of their histologic characteristics. A multilocular pattern was more frequent in the keratinized group of mandibular primordial cysts. In dentigerous cysts, a multilocular pattern was seen only in the keratinized group and the long/short ratio was statistically larger; cyst shape was elliptical along the long axis. CONCLUSION: Our results demonstrated morphologic differences of odontogenic cysts caused by lesion site and keratinization. The dentigerous cyst with predominant keratinization should be included in the primordial cyst (odontogenic keratocyst) group.     

Mediastinal teratomas: review of 15 pediatric cases

One hundred fifty-three children with a teratoma presented to one hospital between 1970 and March 1992. The clinical and pathological features of 15 patients with mediastinal teratomas are reviewed; six were newborn and nine aged from infancy to 13 years. Thirteen patients including the six newborns presented with respiratory distress and all 15 patients had a mass on chest radiograph. A definite diagnosis of teratoma was not made preoperatively in any of these patients. At operation, a median sternotomy was used to approach seven anterior tumors and a lateral thoracotomy performed in the other eight patients. Histologically two were mature, 10 had immature elements, and three were malignant teratomas. The patients with malignant tumors were all over 12 years of age and died within 6 months of treatment. All six neonates had immature teratomas. Raised serum alpha-fetoprotein levels provided useful markers in two patients with recurrent tumors. Three conclusions can be drawn: (1) mediastinal teratomas are rare in children and frequently are not diagnosed before operation; (2) in newborns these tumors may be immature and present with respiratory distress; and (3) a median sternotomy gives excellent exposure for anterior mediastinal tumors.     

Postoperative complications after Mainz pouch construction--with emphasis on measures to deal with narrowing of the duct aperture

Cutaneous sinus tracts in the face and neck region are often dental in origin. The purpose of this study was to characterize the clinical features and treatment of 37 consecutive cases of odontogenic cutaneous sinus tracts, collected and reviewed in a 15-year period. More than half of the patients (21 cases, 57%) were referred from medical doctors, particularly plastic surgeons and dermatologists. The sinus tracts were associated with caries (26 cases), incomplete endodontic treatment (7), crown fracture (2), vertical root fracture (1) and impacted mandibular third molar (1). They occurred most often in adolescents and adults (30 cases, 81%). The most common causative teeth were mandibular teeth (34 teeth, 85%). The chin, submental, and cheek areas were the most common sites of sinus tracts (30 cases, 81%). The majority of causative teeth (32 teeth, 80%) were treated endodontically. All fistulas healed uneventfully after proper dental treatment, without cosmetic surgery. In 63% (20 cases) of the recorded cases, complete resolution occurred within 8 weeks. Half of the patients had had fistulas for more than 6 months before receiving dental treatment, demonstrating that delays in proper diagnosis and treatment were common. As most patients suffered from unnecessary medication or surgery due to the delay of dental treatment, early dental consultation and treatment is important. Conventional endodontic treatment should be the treatment of choice if the tooth is salvageable. The increasing incidence of incomplete endodontic treatment in association with the occurrence of sinus tracts indicates that standardized endodontic therapy should be emphasized for prevention.     

Pericoronal hamartomatous lesions in the opercula of teeth delayed in eruption: an immunohistochemical study of the extracellular matrix

Opercula of teeth delayed in eruption were examined histopathologically and immunohistochemically to determine the possible causes for tooth eruption failure. Specimens were obtained from 58 patients with non-erupted teeth by surgical removal of their gingival opercula. Among the 61 specimens, 31 (50.8%) were diagnosed as pericoronal myxofibrous hyperplasia (PMH), 8 (13.1%) as infantile ameloblastic fibromatosis (IAF), and 19 (31.2%) as odontomas. Histopathologically, PMH is characterized by hyperplasia of odontogenic mesenchymal tissues with a myxoid appearance in which odontogenic epithelial islands and mesenchymal multinucleated giant cells are scattered randomly. Between the mucosal epithelium and the PMH, there is a layer of fibrosis, whose matrix is strongly immunopositive for tenascin. The PMH seems to induce its overlying gingival mucosa to remodel the connective tissue, which obstructs tooth eruption. IAF is usually located adjacent to the PMH and shows an ameloblastic fibroma-like histology with atrophic ameloblastic components and poor encapsulation. The findings suggest that IAF associated with PMH is not a true neoplasm and should be distinguished from ameloblastic fibromas by the name of IAF, and that both lesions are included in the range of hamartomas formed only in the pericoronal tissue of teeth in eruption. We propose to categorize these lesions into a new disease entity of pericoronal hamartomas of odontogenic origin.     

Expression of beta-catenin, alpha-catenin, and E-cadherin in Barrett''s esophagus and esophageal adenocarcinomas

We used a radioactive in situ method to study expression of the RNA component of human telomerase (hTR) during normal human development and differentiation using archival tissues. In embryonic tissues, the highest and most uniform expression was present in undifferentiated neuroepithelium. Expression was stronger in immature epithelium than in accompanying immature mesenchyme. Differentiation of most tissues was accompanied by decreased or absent expression. Except for testis and adrenal, the adult pattern of expression was present by the 10th postnatal week. In adult tissues, high expression was present in the testis (primary spermatocytes and Sertoli cells), moderate expression was present in lymphoid follicles (germinal centers), and weak expression was present in epithelia (regenerative cells) but was absent in the nervous system and mesenchymal derived tissues. Expression in adult tissues was predominantly limited to dividing cells, although certain differentiated postmitotic cells expressed the hTR. Our studies demonstrate the complex interrelationship of hTR expression with human development, differentiation, and cell division.     

The neurotropic activity of peptide immunomodulators

Ultrastructure of dental enamel was examined under electron microscope after exposure to hydroxyethylene diphosphonic (HEDP) acid and prophilometry of enamel surface was carried out after its exposure to acid salts; clinical studies in 105 patients aged 18-50 years with different diseases of hard dental tissues were carried out in order to assess the duration of filling preservation after dental enamel treatment with HEDP salts. Clinical results were assessed from subjective sensations of patients and data of examination. The criteria of assessing the results were presence of a filling in a filled carious cavity, marginal adhesion of the filling, alteration of color along the external interface of the filling, caries relapses, status of dental pulp and periapical tissues. Clinical and laboratory studies showed that treatment with HEDP acid creates favorable conditions for tooth filling.