Robert P. Langlais

Elongated and mineralized stylohyoid ligament complex: A proposed classification and report of a case of Eagle's syndrome

A classification of the radiographic appearance of elongated and mineralized stylohyoid ligament complexes based on three types of complexes--Type I, elongated; Type II, pseudoarticulated; and Type III, segmented--is proposed. These types are further described by a pattern of calcification: calcified outline, partially calcified, nodular, and completely calcified. The classification is illustrated in a case of Eagles syndrome in a 55-year-old Mexican-American man with symptoms of chronic otalgia and cephalgia. The surgical management and follow-up of this patient are discussed.

Relationship between density variability and imaging volume size in cone-beam computerized tomographic scanning of the maxillofacial region: an in vitro study

OBJECTIVE In limited-volume cone-beam computerized tomography (CBCT) imaging, projection data discontinuity caused by maxillofacial hard tissue structures outside the reconstructed volume are reported to affect the density value of the hard and soft tissue structures within the volume. The intensity of this effect is purported to be related to the size of the imaging volume. The aim of this study was to characterize the effect of the size of the scanned volume on density values in vitro. STUDY DESIGN Test objects were positioned in a custom phantom in the following 4 patterns: bimandible and vertebrae, bimandible, left mandible and vertebrae, and left mandible. We used a newly developed flat panel detector CBCT system (Alphard Vega; Asahi Roentgen, Kyoto, Japan) to acquire scans of the left molar region using cylindrical volumes of approximately 5, 10, 15, and 20 cm in diameter and height. The density values of the mandible and the adjacent soft tissue regions were analyzed. RESULTS Highest density variability was observed in the smallest-volume (5 cm) scans. Density variability increased when more objects were included outside the area being imaged. Fewer effects were noted in CBCT scans of larger (10, 15, and 20 cm) volumes. CONCLUSION Larger-volume CBCT scans may yield more consistent density values. Smaller CBCT volumes have the advantages of better image resolution and lower radiation doses. The optimization of the image characteristics is maximized by careful consideration of the purpose of the CBCT examination.

Drug-induced gingival overgrowth.

Certain anticonvulsants, cyclosporine, and a variety of calcium channel blockers have been shown to produce clinically and histologically similar gingival enlargements in certain susceptible patients. These drugs appear to be similar with respect to their pharmacologic mechanism of action at the cellular level. The primary target tissue is the most essential difference among them. Therefore it is tempting to speculate that these agents may act similarly on a common secondary target tissue, such as gingival connective tissue, and cause a hyperplastic response. This tissue reaction may involve a disturbance of calcium ion influx into specific cell populations with a resulting alteration in collagen metabolism and other host cell response mechanisms. A connection between ion exchange, folate uptake, collagenase activation, and bacterial inflammation may exist. Until a more effective approach can be developed from future research results, treatment should continue to emphasize plaque control, professional debridement, and resective gingival procedures to improve function, esthetics, and access for home care.

Evaluation of high-resolution cone beam computed tomography in the detection of simulated interradicular bone lesions

OBJECTIVES The purpose of this study is to assess the accuracy of limited-volume high-resolution cone beam CT (CBCT) in the detection of periodontal bone loss. METHODS 163 simulated periodontal lesions of different depths were created in dried human hemimandibles. Specimens were imaged using the intraoral paralleling technique and limited-volume CBCT (3DX Accuitomo; Morita Co. Ltd, Kyoto, Japan). Ten viewers examined the images. Data were analysed with receiver operating characteristics (ROC) analysis. ROC curves were generated and the areas under the maximum-likelihood curves (A(z)) were compared. Other statistical analyses were used to detect the normality of the distribution of the results. RESULTS The results are reported as the individual viewer ROC curve areas for each of the two imaging modalities. In all experiments the A(z) area for CBCT (0.770-0.864) was larger than the A(z) area for periapical film (0.678-0.783); statistical tests showed a statistically significant difference between the two modalities. CONCLUSIONS Results indicate that the CBCT technique has better accuracy and diagnostic value than periapical films in the detection of interradicular periodontal bone defects.

Jaw and skull changes in neurofibromatosis

Thirty-eight patients with neurofibromatosis were examined clinically and radiographically for manifestations of the disease in the head and neck region. Ninety-two percent of the sample had at least one intraoral or radiographic sign of the disease. This suggests that the incidence of jaw and skull involvement in neurofibromatosis may be greater than previously reported in the literature.

Radiobiologic risk estimation from dental radiology: Part I. Absorbed doses to critical organs

The aim of the present study was to generate one consistent set of data for evaluating and comparing radiobiologic risks from different dental radiographic techniques. To accomplish this goal, absorbed doses were measured in fourteen anatomic sites from (1) five different panoramic machines with the use of rare-earth screens, (2) a twenty-film complete-mouth survey with E-speed film, long round cone, (3) a twenty-film complete-mouth survey with E-speed film, long rectangular cone, (4) a four-film interproximal survey with E-speed film, long round cone, and (5) a four-film interproximal survey with E-speed film, long rectangular cone. The dose to the thyroid gland, the active bone marrow, the brain, and the salivary glands was evaluated by means of exposure of a tissue-equivalent phantom, fitted with lithium fluoride thermoluminescent dosimeters (TLDs) at the relevant locations.

Cross-sectional radiography for implant site assessment

An accurate tomographic technique is described for acquisition of optimal cross-sectional images of implant sites before implant surgery. The described technique is applicable to tomographic systems equipped with a cephalometric head positioner. This cross-sectional tomographic technique was performed on a series of patients and the images of the first 20 patients subsequently evaluated. The cross-sectional images allowed for the characterization of the alveolar crest and visualization of anatomic structures in a buccolingual dimension while providing an accurate estimation of available vertical space from the crest.

Radiobiologic risk estimation from dental radiology. Part II. Cancer incidence and fatality.

With the use of the measured absorbed doses from part I of this article, the specific radiobiologic risk to the patient from (1) five different panoramic machines with rare-earth screens, (2) a 20-film complete-mouth survey with E-speed film, long round cone, (3) a 20-film complete-mouth survey with E-speed film, long rectangular cone, (4) a 4-film interproximal survey with E-speed film, long round cone, and (5) a 4-film interproximal survey with E-speed film, long rectangular cone, was calculated. The estimated risks are expressed in two ways: the probability of radiation-induced cancer in specific organs per million examinations and the probability of expression of a fatal cancer per million examinations. The highest risks calculated were from the complete-mouth survey with the use of round collimation. The lowest risks calculated were from panoramic radiography and four interproximal radiographs with rectangular collimation.

Garré's osteomyelitis: Literature review and case report

Abstract An in-depth review of the literature on Garres osteomyelitis has been presented, along with an additional case, in a 7-year-old Caucasian boy with an unusual presentation. In most instances, the periosteal proliferation is in response to an attenuated infection associated with a periapical inflammation, a recent extraction, or an infected or traumatized operculum. In this case the diagnosis was complicated by an absence of clinical signs, indicating the presence of an attenuated infection. While the appearance of the lesion on occlusal and periapical radiographs was consistent with a clinical diagnosis of Garres osteomyelitis, conditions such as Ewings sarcoma and others could not be eliminated on the basis of the clinical and radiographic findings alone. In this instance a definitive diagnosis could be made only after biopsy.

Xerostomia: Diagnosis and treatment planning considerations

Long-term xerostomia results in a poor prognosis for the remaining dentition, existing restorations, and denture acceptance. The dentist must be able to recognize xerostomia by the clinical signs and the potential for xerostomia on the basis of a medical history, since xerostomia may not always be the patients chief complaint. A literature review concerning the etiology, diagnosis, and management of xerostomia is presented.