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71.
Twenty polyester dental identification microdisks were bonded to the surface of 20 extracted human mandibular molars and placed in 0.9% saline solution for 26 weeks, after which the teeth with bonded microdisks were embedded in bovine muscle tissue and incinerated for 11 minutes. Under the conditions of this study, 2 of the 20 polyester microdisks did not demonstrate deterioration and remained legible after storage in saline. The teeth and bonded microdisks did not appear to be affected by 11 minutes of incineration. A list of ideal characteristics for identification microdisks did proposed.  相似文献   
72.
This paper summarizes and evaluates the oral complications associated with orotracheal intubation in neonates. The palatal defect resulting from orotracheal intubation is best described as palatal grooving, rather than clefting since no oral nasal communication has been demonstrated. Palatal grooving may be caused by the inhibition of the molding tongue forces on the lateral palatine shelves. The incidence of palatal grooving increases with duration of intubation and reportedly resolves following extubation. However, posterior cross-bites, high palatal vaults, and poor speech intelligibility have been reported in children who previously have been intubated. Impingement of an orotracheal tube on the alveolus rather than on the palate may cause alveolar grooving which can cause dilaceration of primary teeth. Bilateral linear enamel hypoplasia in premature neonates is caused by an interruption in amelogenesis from intrauterine disturbances. However, gross unilateral incisal enamel hypoplasia in children who have been intubated is probably due to traumatic intubation. Avoiding excessive pressure on the maxillary alveolus during intubation is suggested. An appliance is available which secures oral tubes and protects the palate and alveolus.  相似文献   
73.
Langerhans cells (LC) are cell types found in the skin and gingiva. LC have immunological functions as phagocytic cells and as antigen-presenting cells for T and B lymphocytes. Sections from biopsies of the gingiva in cases of periodontal disease were found to have increased numbers of LC. These biopsies also contained intragingival bacteria. Serial sections of frozen specimens of human gingiva were prepared for staining. Hematoxylin and eosin were used for tissue survey, the Gram stain for assessment of bacterial invasion, anti-Leu-6 monoclonal antibody associated with peroxidase technique (PAP) to identify LC, antibacterial sera to Bacteroides gingivalis and Actinobacillus actinomycetemcomitans associated with peroxidase to specifically identify these two common periodontopathogenic bacteria. Additional positive identification of bacteria was performed by preparing the same histological section containing gram-stained particles for scanning electron microscope and transmission electron microscope LC confirmation. The results suggest that the increased number of LC seen in diseased sites of oral epithelium containing intragingival microorganisms may be one of the host immune mechanisms to penetration by bacteria.  相似文献   
74.
Thirteen peptidase substrates were hydrolysed by this plaque. After fasting the monkeys for 24 h, the rates of hydrolysis of N-leucyl-, N-alanyl-, N-isoleucyl- and N-tyrosyl-2-naphthylamines, glycyl-L-proline 4-nitroanilide, N alpha-benzoyl-DL-arginine-2-naphthylamine and L-leucyglycine were significantly increased. Changes in these peptidase activities may serve to enhance the mobilization of amino acids and peptides, and they may explain why the growth rates of dental-plaque bacteria in vivo are generally unaffected by the availability of the host's diet.  相似文献   
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Research has shown that cleft lip and palate individuals have higher nasal airway resistance than normal subjects (Warren, Duany, and Fischer, 1969). The present work examined the predictive nature of modeled velopharyngeal orifice area calculations obtained using the hydrokinetic equation (Warren and DuBois, 1964) under conditions simulating increased degrees of nasal obstruction. The results of this project suggested that Warren's hydrokinetic method can be used to obtain accurate estimates of velopharyngeal orifice area under conditions of increased nasal airway resistance when airflow rates are nonvariant.  相似文献   
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78.
The two cases presented here demonstrate a successful therapeutic modality with resection followed by immediate reconstruction with bone grafts. At least one of the cases presented seems to indicate that the tumor is relatively less aggressive than the simple ameloblastoma. The histopathology of the two cases suggests that this odontogenic tumor has a wider histologic variation than originally described by Pindborg.  相似文献   
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