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31.
Pemphigus vulgaris (PV) is an autoimmune disease accounting for 80% of all cases of pemphigus. Before the advent of corticosteroid therapy, pemphigus was fatal, with a mortality rate of up to 75% in the first year. It is still a serious disorder, but the 5% to 10% mortality rate is now primarily due to the side effects of therapy. In 75% to 80% of cases, PV lesions first appear in the oral cavity. Dentists are therefore in a unique position to recognize the oral manifestations of the disease, allowing early diagnosis and initiation of treatment. The diagnosis is based on pathological examination and immunofluorescence testing. Systemic corticosteriods and steroid-sparing agents are the mainstays of treatment; topical corticosteroids may also be used to accelerate healing of persistent oral lesions. This article describes a 71-year-old woman with multiple chronic ulcers in the oral cavity, in whom PV was diagnosed 4 months after the symptoms first appeared. The article also reviews the current literature on diagnosis and treatment of the condition.  相似文献   
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Objectives : An epidemiologic analysis was performed to identify patient and dentist factors influencing over- and undertreatment of restorative services in a sample of insured adults. Methods : At baseline, 681 Washington State employees and their spouses, aged 20 to 34 years and residing in the Olympia or Pullman areas, were interviewed by telephone. Oral assessments were conducted to measure personal characteristics, oral disease, and restoration quality. Adults were followed for two years to measure use of restorative services from dental insurance claims. Each adult's baseline and claims data were linked with provider and practice variables collected from the dentist who provided treatment. Results : For overtreatment, 39 percent of adults received one or more replacement restorations in nondecayed teeth with satisfactory fillings at baseline, while 18 percent of adults had one or more restorations placed in teeth with no decay and fillings. An adult's probability of overtreatment was higher if the adult had more fillings at baseline, or if an adult's dentist was younger, had a busy practice, advertised, charged higher fees, had less continuing education, or had a solo practice. For undertreatment, about 16 percent of adults either received no replacement restorations in teeth with unsatisfactory fillings at baseline, or had decayed teeth at baseline that were not filled or crowned. An adult's probability of undertreatment was higher if an adult had less decayed or more missing surfaces at baseline, or if an adult's dentist believed in sharing information with patients, had a busy practice, or reported not placing fillings when radiographic evidence of new caries was present. Conclusion : A minority of adults aged 20 to 34 experienced potential over- or undertreatment of restorative services, which are influenced by both patient and dentist factors.  相似文献   
34.
Matrix metalloendoproteinase inhibitor (TIMP) is constitutively expressed by a variety of cells and is present in most connective tissues, and in serum and amniotic fluid. In our previous studies, collagenase inhibitor activity has been identified in saliva (5). To determine the nature of this inhibitor, fresh human parotid saliva was first concentrated by ammonium sulfate precipitation and the 20–60% saturated ammonium sulfate fraction containing the inhibitor activity was chromatographed on an AcA 54 gel filtration column. The inhibitor eluted with an apparent Mr of 29000 and a 42-fold purification was achieved. For characterization, the inhibitor was further purified by heparin-Sepharose chromatography. The inhibitor, which bound to heparin-Sepharose in 0.0 M NaCl at neutral pH and remained bound after a 0.18 M NaCl step elution, was eluted with 0.25 M NaCl. The partially purified inhibitor was characterized by its stability at low pH (pH 2.0) and after heat treatment (60° C and 95° C), and by its resistance to organomercurial (APMA) and trypsin treatments. These properties, together with immunoreactivity with an anti-human TIMP polyclonal antibody on immunoblots. are consistent with the collagenase inhibitor activity being TIMP. Collagenase in either the active or precursor forms was not delected in parotid or submandibular ductal saliva nor after AcA 54 chromatography of parotid ductal saliva. The presence of TIMP in saliva has important implications. First, it has the potential to suppress the activity of matrix metalloendoproteinases released during periodontal inflammation; and second, in the analysis of collagenolytic enzymes in gingival crevicular fluid, it is clear that care must be taken to avoid contamination of the crevicular fluid with saliva.  相似文献   
35.
BACKGROUND: Allergies to natural rubber latex (NRL) were unknown in dentistry until 1987. That changed with the publication of a report documenting NRL-based anaphylaxis in a dental worker. This case and others prompted regulatory and manufacturing changes in rubber products and increased awareness throughout the profession. However, other common dental chemicals cause allergic reactions and irritation and often are handled with insufficient precautions. Although recognition of NRL allergy has improved, awareness of other potential allergens and irritants in dentistry still is limited. OVERVIEW: Recent research indicates that the prevalence of NRL protein allergy may be decreasing. In contrast, occupation-related dermatoses associated with other dental products may be more common. Encounters with bonding agents, disinfectants, rubber, metals and detergents can cause occupation-based irritant contact dermatitis and allergic contact dermatitis. These conditions may be found in more than one-quarter of dental and medical personnel. Therefore, dental-specific information about the recognition and management of allergic and irritant reactions is needed. CONCLUSIONS AND CLINICAL IMPLICATIONS: The prevalence of occupation-related dermatitis may be increasing in dentistry. Reducing exposure to potential irritants and allergens and educating personnel about proper skin care are essential to reversing this trend.  相似文献   
36.
OBJECTIVE: Even though some chemical agents can disinfect biofilms in dental unit waterlines, there remains concern that all remnants of the biofilm matrix are not eliminated. Even with periodic treatments, the bacterial populations in dental unit waterlines recur rapidly. In addition, with some previously tested products, patient safety, as well as toxic, caustic and corrosive residual chemicals are also a concern. This study evaluated ICX, A-dec's new water treatment solution, in a series of experiments for prevention, microbial spectrum of activity, minimum inhibitory time determination, and treatment of established biofilms. METHODOLOGY: New dental unit waterline tubing was treated continuously during simulated patient care over 28 days with municipal water. It was then treated with ICX. Effluents from lines with established biofilms (averaging > 10(4) CFU/ml at day 0) were treated to assess levels of CFU counts within 21 days of exposure to ICX. RESULTS: Tubing treated with ICX did not develop a detectable biofilm using ruthenium red staining, and microbes in effluents remained undetectable. CONCLUSION: ICX is effective in maintaining the effluent within the American Dental Association's and the Centers for Disease Control's recommendation for < 500 CFU/ml. In addition, considering the preliminary finding that ICX reduces microbial contamination of effluents from established biofilm lines, it may be useful in long-term treatment alone or when coupled with a shock treatment to assist in biofilm destruction.  相似文献   
37.
Many authors have studied the correlation of cranial base flexure and the degree of mandibular prognathism and classification of malocclusion. This indicates that the cranial base flexure may or may not have an effect on the degree of mandibular prognathism and classification of malocclusion. This study evaluates the correlation of the pretreatment cranial base angle and its component parts to other dental and skeletal cephalometric variables as well as treatment time. The sample consisted of 99 Angle Class II and Class I malocclusions treated in the mixed dentition with cervical headgear and incisor bite plane. Thirty of the patients required full appliance treatment. Treatment duration averaged 4.3 years (SD, 1.5 years). Only the starting cephalograms were used to acquire linear, proportional, and angular cranial base dimensions using Ba-S-N (total cranial base), Ba-S/FH (posterior cranial base), and SN/FH (anterior cranial base). Pearson product moment correlation coefficients were computed and used to assess the association of the following skeletal and dental variables: N-Pg/FH, MP/FH, Y-axis/FH, U1/L1, L1/MP, A-NPg mm, A-Perp, B-Perp, and treatment time with the cranial base measurements. Significance was determined only when the confidence level was P < .05. Although there was no significant correlation of BaSN or SN/FH with NPg, the angular BaS/FH, linear BaS mm, and proportional length of BaS %BaN were all statistically negatively correlated to the facial angle. This indicates that the posterior cranial base leg is the controlling factor in relating the cranial base to mandibular prognathism.  相似文献   
38.
Abbey LM 《Dental clinics of North America》2002,46(3):575-87, vii-viii
Transfer of knowledge from the basic biopsychosocial sciences to patient care is a major task for dental students during their education. Computer-based interactive patient simulations can help students affect this transfer because simulations allow students to develop and practice problem solving and decision-making skills interactively within the context of patient problems. A program for authoring computer-based interactive simulations is described. Patient simulations can effectively integrate basic science relevance, preparation for clinical problem solving, teaching new clinical content and several other necessary elements into curriculum infrastructure. Case simulations also can contribute to evolving educational standards set out by accrediting bodies.  相似文献   
39.
Within the last 20 years there has been a decrease in the caries prevalence of US schoolchildren, a change in the intraoral caries pattern, and a slowing of the progress of lesions. Simultaneously, the prevalence of enamel milder, cosmetically acceptable forms and is more noticeable in fluoride-deficient communities than those with optimal or above-optimal water fluoride concentrations. Circumstantial evidence indicates that a principal contributor to the caries decline is the extensive use of fluoride dentifrices. Conversely, although use of a fluoride dentifrice can add to the total daily amount of ingested fluoride in preschool children, there is little evidence to suggest that dentifrice ingestion is a principal factor causing the fluorosis increase. The value of fluoride methods may be assessed in relative or absolute terms. The relative, or percentage, caries reduction attributed to fluoride mouthrinses and gels appears to be a property intrinsic to the methods themselves and generally is little affected by the caries activity of the population being treated. Conversely, the absolute, or numerical, caries reduction is dependent upon the level of disease in the population. Thus, the reported caries decline reduces the number of surfaces prevented from developing caries, even though the percentage reduction remains substantially unchanged. Although inadvertent ingestion of fluoride can result from the use of mouthrinses and gels, there is little evidence to suggest that they have contributed to the fluorosis increase. When using topical methods, prudence should prevail to avoid ingestion of fluoride. Fluoride dentifrices should continue to be used routinely, and although lower potency dentifrices may be considered, the literature does not provide strong support for their need. Use of fluoride mouthrinses and gels for individual patients should be predicted upon their caries activity or risk. Use of these methods in public health programs is a matter of cost-effectiveness, which will be influenced by the caries prevalence of the target population.  相似文献   
40.
Teeth with vertical root fractures (VRFs) have complete or incomplete fractures that extends through the enamel, dentin and pulp, down the long axis of the tooth. Several different variables were investigated and statistically evaluated as to their correlation with the presence of VRFs. Specifically analyzed were gender, tooth location, age, radiographic and clinical findings, bruxism, and pulpal status. The data were collected from three different endodontists, from three different geographic locations, comprising a total of 227 teeth. Although VRFs may occur in conjunction with any of the parameters investigated, only certain factors were found to occur in a significant number of cases. The results indicate that VRFs are statistically more prevalent in mandibular molars and maxillary premolars. They are associated with periradicular bone loss, pain to percussion, extensive restorations, and seem to occur more often in females and older patients. However, VRFs are not necessarily related to periapical bone loss, a widening of the periodontal ligament space, associated periodontal pockets, a sinus tract, particular pulpal status, or bruxism.  相似文献   
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