Development of a hardened THz energy meter for use on the kilojoule-scale, short-pulse OMEGA EP laser.

A highly adaptable and robust terahertz (THz) energy meter is designed and implemented to detect energetic THz pulses from high-intensity (>1018 W/cm2) laser-plasma interactions on the OMEGA EP. THz radiation from the laser driven target is detected by a shielded pyrometer. A second identical pyrometer is used for background subtraction. The detector can be configured to detect THz pulses in the 1 mm to 30 µm (0.3- to 10-THz) range and pulse energies from joules to microjoules via changes in filtration, aperture size, and position. Additional polarization selective filtration can also be used to determine the THz pulse polarization. The design incorporates significant radiation and electromagnetic pulse shielding to survive and operate within the OMEGA EP radiation environment. We describe the design, operational principle, calibration, and testing of the THz energy meter. The pyrometers were calibrated using a benchtop laser and show linear sensitivity to up to 1000 nJ of absorbed energy. The initial results from four OMEGA EP THz experiments detected up to ∼15µJ at the detector, which can correspond to hundreds of mJ depending on THz emission and reflection models.

First measurements of remaining shell areal density on the OMEGA laser using the Diagnostic for Areal Density (DAD).

A glass Cherenkov detector, called the Diagnostic for Areal Density (DAD), has been built and implemented at the OMEGA laser facility for measuring fusion gammas above 430 keV, from which remaining shell ⟨ρR⟩ abl can be determined. A proof-of-principle experiment is discussed, where signals from a surrogate gas Cherenkov detector are compared with reported values from the wedge range filter and charged particle spectrometer and found to correlate strongly. The design of the more compact port-based DAD diagnostic and results from the commissioning shots are then presented. Once absolutely calibrated, the DAD will be capable of reporting remaining shell ⟨ρR⟩ abl for plastic and glass capsules within minutes of a shot and with potentially higher precision than existing techniques.

A picosecond beam-timing system for the OMEGA laser.

A timing system is demonstrated for the OMEGA Laser System that guarantees all 60 beams will arrive on target simultaneously with a root mean square variability of 4 ps. The system relies on placing a scattering sphere at the target position to couple the ultraviolet light from each beam into a single photodetector.

Otodental syndrome: a case presentation in a 6-year old child.

BACKGROUND: Otodental syndrome is a rare condition characterised by globodontia, and sensorineural high frequency hearing loss. To date, only 20 cases of otodental syndrome have been reported. CASE REPORT: A 6 year-old girl presented with a chief complaint of delay in the eruption of primary canines. Following clinical, radiographic and audiologic evaluations, the patient was diagnosed with otodental syndrome. CONCLUSION: Globodontia is a diagnostic feature of the otodental syndrome, which often provides the path to discovery of the associated hearing loss. Missing teeth, arch-size discrepancies, chewing problems and teething disturbances are the other major complications.

Ameloblastic fibro-odontoma: a clinicopathologic study of 12 cases.

OBJECTIVE: The ameloblastic fibro-odontoma (AFO) is an uncommon odontogenic tumor occurring in childhood with limited reported data on recurrence. The purpose of this AFO study was to review its clinicopathologic features, investigate treatment modalities and establish a recurrence rate. STUDY DESIGN: The clinicopathologic features of 12 new cases of AFO were analyzed and compared with those of 208 cases from the literature, with special emphasis on the clinical behavior, treatment, and recurrence rate. RESULTS: The average age was 9.4 (+/- 6.7) years with a male-to-female ratio of 1.6:1. The mandible was the site of occurrence in 59.5%. The tumor most often presented radiographically as a unilocular mixed density lesion associated with the crown of an impacted tooth. Displacement of teeth, delayed eruption and bony expansion were commonplace. There were 5 recurrences among 68 cases with adequate follow-up for a recurrence rate of 7.4%. All recurrences were attributed to incomplete removal at the time of the initial surgery. CONCLUSIONS: The AFO is a childhood tumor most often affecting the posterior jaws and frequently causing bony expansion with profound affects on the dentition. Conservative surgical removal with extraction of the associated teeth is recommended. The established recurrence rate is less than 10%.

Peripheral ossifying fibroma--a clinical evaluation of 134 pediatric cases.

PURPOSE: Reported clinicopathologic studies on the peripheral ossifying fibroma (POF), a reactive gingival lesion, have not addressed the pediatric population in specific detail. This study, the first devoted to children, investigated the clinical features of a large number of POFs and compared the findings to cases reported in the English language literature. METHODS: Detailed clinical and historical information of 134 surgically removed POFs in patients aged 1-19 formed the basis of this study. Clinical manifestations, histogenesis, treatment rationale with pediatric considerations, and biologic behavior were emphasized. RESULTS: The POF was found more frequently in females (60%). It had a predilection for the maxillary gingiva (60%) and for the incisor/cuspid region. The average patient age was 14 years. Only 2 (1%) POFs were found to be unequivocally associated with primary teeth. The clinician seldom included the POF in the differential diagnosis. The recurrence rate after surgical excision was 8%. CONCLUSIONS: This study revealed that a POF arising from the periodontal ligament of a primary tooth is most likely a rare event. However, the pediatric patient with a POF has special management considerations compared to the adult. Because of the POF behavior pattern, a proper treatment protocol is warranted with close postoperative follow-up.

Ductal papillomas of salivary gland origin: A report of 19 cases and a review of the literature.

The term ductal papilloma is used to identify a group of 3 rare benign papillary salivary gland tumors known as inverted ductal papilloma, sialadenoma papilliferum, and intraductal papilloma. They represent adenomas with unique papillary features and arise from the salivary gland duct system. We describe the clinical and microscopic features of 19 new cases of ductal papillomas and combine them with 116 cases previously published in the English-language medical literature. These 19 cases were composed of 13 inverted ductal papillomas, 3 sialadenoma papilliferums, and 3 intraductal papillomas. Collectively, these 19 ductal papillomas occurred most commonly in the sixth to eighth decade of life, with an average patient age of 54 years. Men predominated 1.37:1. The sialadenoma papilliferums presented as papillary lesions clinically with all 3 misinterpreted as squamous papillomas by the surgeons. The inverted ductal papillomas and intraductal papillomas appeared as submucosal nodules. The lip and the palate were the most common locations for inverted ductal papilloma and sialadenoma papilliferum, respectively. The sites for the 3 intraductal papillomas were the parotid papilla of the Stensen's duct, the upper lip, and the buccal mucosa. With light microscopy, inverted ductal papillomas appeared to arise from the excretory ducts near the mucosal surface, whereas intraductal papillomas appeared to arise from the excretory ducts at a deeper level. Sialadenoma papilliferum had a more complex histology, with a biphasic growth pattern of exophytic papillary and endophytic components. All 19 cases were treated by surgical excision. Follow-up information was available in only 2 cases, both inverted ductal papillomas. Neither case recurred during a 20-year period. Sialadenoma papilliferum, with a literature-derived recurrence rate of 10% to 15%, seems to assert a more significant biological behavior than inverted ductal papilloma and intraductal papilloma. Our findings justify the separation of these 3 entities based on clinical and histologic parameters. They are tumors of adulthood and, in addition, have in common their relationship to the excretory duct system, their anatomical distribution, and their general behavior.

Benign fibro-osseous lesions: a review of current concepts.

The benign fibro-osseous lesions (BFOL) represent a clinically diverse group of disorders of bone that share similar histopathologic features. As a group, they are relatively common in the craniofacial complex, especially the jaws. Although the general concept of BFOL is relatively well known, specific diagnostic interpretation of individual cases is often challenging. New concepts and controversies have arisen over the past 10 to 15 years regarding classification and diagnostic criteria. However, among the new theories and contentions, there is now essential agreement that the osseous dysplasias represent a single disease process, while the so-called "juvenile active ossifying fibroma" and other "aggressive," "active," "psammomatoid" ossifying/cementifying fibromas remain controversial. This review is presented to update the surgical pathologist on the various entities comprising the spectrum of BFOL and to examine the criteria for their diagnosis.

Tenerife revisited: the critical role of dentistry.

The authors record the contribution of dentistry to the identification of victims of one of the most significant disasters in the history of aviation-the March 1977 collision of two Boeing 747 jumbo jets in the Canary Islands, which resulted in 583 fatalities. Dental identification was the primary method of victim identification because a high percentage of the bodies were severely burned. Virtually all aspects of the U.S. identification efforts have been reported with the exception of the valuable role of dentistry. The dental team's organization, methodology, and significant contributions to forensic dentistry and a variety of remarkable problems that the team encountered are documented.

Subacute necrotizing sialadenitis: report of 7 cases and a review of the literature.

Subacute necrotizing sialadenitis (SANS) is a nonspecific inflammatory condition of unknown etiology affecting oral minor salivary glands. The lesion is most often characterized by a localized palatal swelling, accompanied by an abrupt onset of pain. In this report, we describe the clinical, microscopic, and ultrastructural features of 7 new cases of SANS and combine them with those of 15 cases previously published in the English language medical literature. Patient ages ranged from 15 to 45 years, with a mean age of 21.9 years. A male to female ratio of 3.4 to 1 was observed, but probably reflects a male sampling bias because 14 of the 22 cases occurred in a military population. Seventeen cases occurred on the hard palate, 4 on the soft palate, and 1 on the tonsillar pillar. The lesions were nonulcerated swellings ranging in size from 0.3 to 2.5 cm in diameter. All lesions except one were painful, and most had been present for a week or less at the time of diagnosis. Histopathologic features included diffuse involvement of minor salivary glands by lymphocytes, histiocytes, neutrophils, and variably by eosinophils. Loss of acinar cells, early acinar cell necrosis, and atrophy of ductal cells were also observed. Although possible viral particles have been reported ultrastructurally in some cases of SANS, none were observed in our study. SANS appears to be a self-limiting process with most cases resolving 2 to 3 weeks after biopsy. SANS has been questioned as an entity by some investigators who prefer to include it within the spectrum of necrotizing sialometaplasia. However, we believe there is justification for the separation of these 2 entities based on clinical and histopathologic parameters. Although the specific etiology of SANS remains unknown, it most likely represents an infectious process or perhaps an immune response to an unknown allergen.

The role of the dental hygienist in mass disasters.

The authors examine the specialty of dental hygiene and address its role in the identification of mass-disaster fatalities. Very little exists in the literature on what dental hygienists can often and what they have contributed as members of dental-identification teams. To encourage forensic dentists to seek out the valuable assistance of these highly trained professionals, the authors illustrate how their services can be used in mass disasters.

Problems in mass-disaster dental identification: a retrospective review.

A wide variety of problems may prevent or hinder a dental-identification (ID) team in its efforts to identify mass casualties. Since these problems have been infrequently reported in a comprehensive manner, the authors identified and summarized these problems to increase the awareness of dental-ID team members and to prepare them for future mass-disaster missions. The authors analyzed 50 mass disasters--ten in which the authors as members of military dental ID teams played a major role and 40 from the literature--and summarized problems that they confronted.

Oncocytoid artifact of the parotid gland: a newly reported artifact.

Electrocautery can induce significant alterations in the connective tissues and epithelium of specimens removed for diagnostic or therapeutic purposes. When electrocautery is used during parotid surgery, it can cause an oncocytoid artifact. The alterations described in this article are enlarged, tightly packed serous acinar cells with coarse to granular eosinophilic cytoplasm, distinct cell borders, and round basal nuclei that on cursory microscopic examination resemble oncocytes with respect to morphology. These changes are seen in conjunction with other, more recognized changes secondary to electrocautery and are believed to occur as a consequence of the electrothermal discharge. On the basis of our findings, this artifact is common is parotid surgical specimens and was misdiagnosed as benign oncocytic lesions in 5 cases.

Ameloblastic carcinoma of the mandible.

BACKGROUND: Ameloblastic carcinoma is a rare, aggressive odontogenic neoplasm of the jaws in which the epithelial cells exhibit cytologic features of recognizable ameloblastoma and malignancy. Cases with metastasis have been infrequently reported. METHODS: A case of a 64-year-old white woman with mandibular ameloblastic carcinoma with documented distant metastasis is presented. The patient's presenting symptoms included facial asymmetry of the right jaw over 2 months and the development of moderate trismus. Clinical manifestations, pathology, treatment, and biologic behavior are discussed. The nomenclature and classification of odontogenic carcinomas are reviewed, including entities that should be considered in the differential diagnosis. RESULTS: The patient underwent surgical resection consisting of mandibulectomy, parotidectomy, and modified radical neck dissection followed by radiation to both necks and tumor bed. Postsurgically, the patient developed pulmonary metastasis at 11 months and expired with widespread metastatic disease at 28 months. CONCLUSIONS: This case demonstrated an unusual behavior pattern in that local recurrence and regional metastasis did not occur. Distant metastasis occurred despite apparent adequate control of the primary mandibular tumor. The ameloblastic carcinoma is a highly malignant neoplasm which requires aggressive therapy. Prognosis is poor. Further reporting of ameloblastic carcinoma is encouraged.

Fibromatosis of the oral and paraoral region.

The fibromatoses represent a group of infiltrating fibrous proliferations that exhibit a clinical behavior and biologic potential intermediate between benign fibrous lesions and fibrosarcoma. The head and neck region is a common site of involvement for these lesions especially in children and young adults. However, the oral structures per se are not often the site of origin. In this study of 31 cases of fibromatosis that involved the oral and paraoral region, patient ages ranged from birth to 51 years with 74% appearing in the first decade. The most common clinical presentation was a painless mass that involved the cheek, tongue, or submandibular region. Erosion of bone was a frequent finding in lesions arising in soft tissue contiguous with the jaws. After surgical excision, lesions recurred in five patients for a recurrence rate of 23.8%. One lesion recurred twice. The average interval from initial treatment to recurrence was 7.6 months. The recurrence rate observed in this series is significantly lower than that generally reported for fibromatosis of the head and neck (50% to 70%). This is most likely due to the exclusion in this investigation of lesions in the supraclavicular region.

Cartilage in the walls of odontogenic keratocysts.

Only one histologically documented case of cartilage in the wall of an odontogenic keratocyst has been reported in the English language literature. Four new cases are presented with the clinical, radiographic and histopathologic features described. To our knowledge this finding has not been reported in association with any other type of odontogenic cyst.

Utilization of an oral pathology service: a professional responsibility.

The role of oral pathologists as members of the comprehensive health care team is reviewed. The importance of utilizing an Oral Pathology Service in the everyday practice of dentistry and medicine and the inherent medicolegal considerations are discussed. Standards of care for submission of surgically removed oral tissues is an issue that warrants further delineation.

Necrotizing sialometaplasia. A clinicopathologic study of sixty-nine cases and review of the literature.

The clinicopathologic findings in 69 cases of necrotizing sialometaplasia (NS) were analyzed and compared with 115 reported cases of NS in the English-language literature. Data comparing age, sex, race, location, clinical presentation, and possible predisposing factors are summarized. Analysis of the data indicates that NS can occur in a variety of clinical settings and may exhibit a spectrum of histologic features. Recognition of NS, regardless of its clinical or microscopic presentation, is essential to avoid inappropriate or unnecessary treatment for this benign reactive process.

Bilateral traumatic bone cysts of the mandible: an unusual clinical presentation.

This case report describes an unusual clinical presentation of bilateral traumatic bone cysts of the mandible. These lesions presented clinically as bilateral dentigerous cysts associated with the mandibular third molar teeth. Because of this unusual presentation, a combination of clinical examination, thorough history, radiographic studies, surgical exploration, and microscopic evaluation was necessary in order to render a definitive diagnosis on this case. Knowledge and awareness of these features are important to assist in the initial diagnosis as well as patient management and follow up.