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991.
Oral exophytic lesions in 23,616 white Americans over 35 years of age   总被引:2,自引:0,他引:2  
This study provides the first detailed epidemiologic analysis of benign oral soft tissue masses and bony prominences. Of 1,453 such lesions found in 23,616 white persons over 35 years of age, the most common were palatal and mandibular tori, with a combined prevalence rate of 27.1 lesions/1,000 persons. Other lesions commonly found were irritation fibromas (12.0 lesions/1,000 population); hemangiomas (5.5/1,000); papillomas (4.6/1,000); epulides fissurata (4.1/1,000); mucoceles (2.5/1,000); and others. The prevalence of all oral masses was 61.4/1,000 (33.5 if bony lesions are excluded). Sex-specific and site-specific clinical information is offered and is contrasted with the literature.  相似文献   
992.
993.
994.
Ten patients undergoing treatment with bridges supported by osseo-integrated oral titanium implants were studied regarding the oral microflora. Saliva samples for microbiological studies were collected before the abutment operation, 1 week after the operation, after the bridges were inserted and again 52 weeks after the abutment operation. The implants did not induce colonization with "plaque streptococci" such as Streptococcus mutans and Streptococcus sanguis. A marked colonization with potentially pathogenic microorganisms such as Staphylococcus aureus, Pseudomonas species and enterobacteria was observed after the abutment operation. This was probably due to the use of surgical dressing.  相似文献   
995.
The pathway and synaptic basis for the efferent discharge in the digastric nerve evoked by stimulation of the orbital cortex were studied in cats anesthetized with alpha-chloralose. Transection of the brain stem at the boundary between the pons and the medulla oblongata abolished discharge. Intracellular recording from anterior digastric motoneurones revealed that the orbital cortical stimulation evoked excitatory post-synaptic potentials with a latency that was longer by one synaptic delay than that of spike potentials evoked in medial bulbar reticular neurones making a direct excitatory projection to anterior digastric motoneurones. It was concluded that the excitatory effects was mediated by the medial bulbar reticular formation.  相似文献   
996.
Cultured epithelial cells (E-cells) derived from the rests of Malassez exhibited a diploid karyotype with a modal number of 38 chromosomes, which is the number reported for the pig. Unlike the cell rests in vivo, which appear to be quiescent, E-cells in culture secreted several proteins. The doubling time of E-cells was 36 h. 80 per cent remained sufficiently viable to attach to the culture dish after extensive trypsinization. Their size distribution was unchanged over 9 subcultures. The E-cells secreted prostaglandins of the E and F series into the culture medium. As prostaglandins have been implicated in bone resorption associated with dental cysts, prostaglandin production by epithelial cells derived from the rests of Malassez may contribute to the mechanism of cyst growth.  相似文献   
997.
998.
A study of 43 pediatric oral surgery patients was conducted in a clinical environment. The anesthetic regimen of a minimum dose of ketamine hydrochloride, nitrous oxide-oxygen, and a local anesthetic was tested for recovery time and degree of acceptance by parents and patients. With this regimen, the average recovery time from completion of the procedure was 30 minutes. The combination of these drugs provided a rapid, smooth induction, additional time while the ketamine-induced anesthesia was dissipating, no major complications, and good acceptance by parents and patients.  相似文献   
999.
1000.
Controlled mechanical stimulation of the upper lip in seven subjects resulted in a period of complete or partial inhibition of the electromyographic activity of the masseter muscle. When a painful stimulus was delivered to the lip, a later inhibitory period with a more variable duration was produced. Innocuous stimulation at various intraoral sites led to an early inhibitory period with characteristics similar to those of inhibition produced by innocuous lip stimulation. An increase in stimulus intensity to a noxious level resulted in a second period of inhibition comparable to that produced by noxious lip stimuli. The intensity of the stimulus and the level of muscle activity maintained by the subject were found to influence the incidence and duration of the inhibitory periods. Thus, innocuous and noxious stimulation, whether applied intraorally or extraorally, may result in two distinct periods of inhibition in the jaw-closing muscles. The role in orofacial function of the first inhibitory period has yet to be demonstrated, but the second period is probably involved as a protective reflex.  相似文献   
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