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991.
INTRODUCTION: Ammonia production from the metabolism of urea by urease enzymes of oral bacteria moderates plaque acidification and may inhibit dental caries, as suggested by in vitro studies and indirect clinical observations. The objective of this study was to examine the relationship of urease activity with dental caries at the clinical level. METHODS: Urease activity was measured in dental plaque and saliva samples from 25 caries-free subjects (CF) and in eight subjects with six or more open caries lesions (CA). Plaque and saliva collection was repeated for each subject 1 week later using identical procedures. RESULTS: Urease-specific activity in the dental plaque of CF subjects was significantly higher compared to that in the subjects with caries. The association of low plaque urease levels with increased caries was further supported by odds ratio analysis using different plaque urease cut-off points. Using a receiver operating characteristic curve it was estimated that there was an approximately 85% probability of correctly classifying the subjects as CA or CF based on the relative ordering of their plaque urease activity levels. No statistically significant differences were observed in salivary urease activity. CONCLUSION: This study suggests that loss of alkali-generating potential of tooth biofilms via the urease pathway has a positive relationship to dental caries.  相似文献   
992.
Attention deficit hyperactivity disorder (ADHD) is a common developmental disorder. The present study tested the hypotheses that children with ADHD, particularly those exhibiting severe hyperactivity and impulsivity, have a different stress reaction (measured by salivary cortisol) during a dental recall visit and are more dentally anxious than children in a control group. Eighteen children with ADHD and a control group of 71 children, all 13 yr of age, underwent a clinical dental examination and completed the Corah Dental Anxiety Scale (CDAS). Four saliva samples were gathered for analysis of cortisol: one prior to dental examination, one after, and two the following morning. The subgroup ADHD with hyperactivity/impulsivity had statistically significantly lower cortisol levels than the control group 30 min after awakening. When cortisol values were plotted on a timeline, this subgroup always had lower cortisol concentrations than children in the control group. There was a significant correlation between CDAS scores and cortisol concentrations prior to the dental examination in both the ADHD and the control group. Behavioral expressions of anxiety in children with ADHD may be different from those in other children, not only due to the characteristics of their disorder, but also because of lower stress reactivity.  相似文献   
993.
OBJECTIVE: Poor oral health has been reported to be a risk indicator of mortality, however, few data are available regarding the relationship between chewing ability and mortality. We examined the relationship between self-assessed chewing ability and mortality in elderly subjects. DESIGN: Prospective study. SUBJECTS AND METHODS: Participating in the study were 697 people (277 males, 420 females) from 1282 individuals (80 years old) residing in Fukuoka Prefecture, Japan. Data on oral and systemic health status through questionnaires, accompanied by physical and laboratory blood examinations were obtained. Chewing ability was assessed based on the number of types of food each subject reported as able to chew by questionnaire. RESULTS: A total of 108 subjects died between 1998 and 2002. Those with the lowest number of chewable foods were associated with higher risk of mortality than those with the ability to chew all of the 15 types of food surveyed [hazard ratio (HR) = 2.38, 95% confidence interval (95% CI) = 1.07-5.29], though other parameters including current smoking, low serum albumin, and poor physical health status were more significant. Further, reduced chewing ability of soft foods increased the risk (HR = 2.65, 95% CI = 1.20-5.87). CONCLUSION: Chewing ability was associated with mortality in a population of 80-year-old community residents, and may be a predictor for survival rate.  相似文献   
994.
BACKGROUND: Limited published scientific evidence is available to provide guidance to clinicians on possible increased risks of invasive oral procedures associated with the human immunodeficiency virus (HIV) status of the patient. The aim of this study was to assess post-procedural complications in patients infected with HIV. MATERIAL AND METHODS: This was a retrospective cross-sectional study of the records of 101 consecutive HIV patients treated at the School of Dentistry of Madrid Complutense University and Sandoval STD Clinic in Madrid between January 2003 and February 2005. Data were gathered by an experienced dental practitioner using a structured epidemiological questionnaire for information on gender, age, HIV transmission category, medical history, hepatitis B virus (HBV) or hepatitis C virus (HCV) coinfection and other diseases, TCD4+ and TCD8+ count, HIV viral load (VL), platelet count, neutrophil count, international normalized ratio and haemoglobin level; tobacco and alcohol intake, highly active antiretroviral treatment and presence of oral lesions. Information was also collected on complications related to dental treatment (invasive or non-invasive) during the previous 6 months. Chi-squared test and Fisher's exact test were used to establish statistical significance. RESULTS: Data were gathered on 314 dental procedures in 101 patients. The overall complication rate was 2.2% (7/314); in 147 invasive procedures, seven complications (4.8%) were documented (one persistent pain, two prolonged bleeding, three infections, one bone sequestrum) including extractions, periodontal scaling, endodontic treatment and biopsy. No differences were found in TCD4+, TCD8+, platelet count, HBV or HCV co-infections or HIV VL between patients with and/or without complications. Patients with complications were mainly in B stage of HIV disease (P=0.020). Oral lesions and smoking habit>20 cig day-1 were documented in 83.3% (P=0.086) and 50% (P=0.060), respectively, of patients with complications. CONCLUSIONS: The complication rate was 2.2% overall and 4.8% after invasive dental procedures. Presence of oral lesions, smoking habit or HIV clinical stage B may be predictive factors for oral complications in HIV patients. No relationship was found between complications and virological, immunological or other laboratory values. Studies with wider samples and negative control group are warranted to confirm the absence of an association between HIV positivity and higher risk of oral complications.  相似文献   
995.
Siwiec RM  Solomon GD 《Headache》2007,47(10):1449-1450
Carotid artery dissection has been reported to occur spontaneously and after many types of neck trauma. A case patient is presented who developed a right-sided oculosympathetic palsy and was found to have bilateral carotid artery dissection after she visited her dentist. To the best of our knowledge, this case represents the first report of bilateral carotid dissection following dental work.  相似文献   
996.
BACKGROUND: Few published reports in the dental literature have focused on adult attention-deficit/hyperactivity disorder (ADHD) and its dental implications. TYPES OF STUDIES REVIEWED: The authors conducted a MEDLINE search for the period 2000 through 2005 using the terms "adult" and "attention-deficit" to define ADHD's pathology, medical treatment and dental implications. RESULTS: ADHD is a developmental condition that affects slightly more than 4 percent of the adult U.S. population. Its symptoms include inattention, hyperactivity and impulsivity that can cause personal, social, occupational and leisure-time dysfunction. Medications used to treat the disorder include stimulants, selective noradrenergic uptake inhibitors and tricyclic antidepressants. CLINICAL IMPLICATIONS: The oral health of people with ADHD may be compromised by inattention and impulsivity that impair home care regimens and can lead to cigarette addiction, which may cause oral cancer and damage the periodontium, and excessive ingestion of caffeinated sugar-laden soft drinks that promote dental caries. To safely care for this patient population, dentists must be familiar with the stimulant and nonstimulant medications used to treat adult ADHD, because these drugs can cause adverse orofacial and systemic reactions and interact adversely with dental therapeutic agents.  相似文献   
997.
BACKGROUND: The authors conducted an in vitro study to evaluate the effect of an at-home bleaching product on the microhardness of six restorative materials under different surface treatments. METHODS: Four resin-based composite materials (a hybrid, flowable, microhybrid and nanohybrid), an ormocer (organic modified ceramic) material and a ceramic material were bleached with 15 percent carbamide peroxide. The authors prepared two groups of samples (polished and unpolished) (n = 7) from each resin-based composite material and the ormocer. The authors polished all of the samples in the ceramic group. Two samples from each group served as negative controls. The authors measured the microhardness of the samples before bleaching, after eight hours and 56 hours of bleaching, and 24 hours and one month after the end of bleaching. RESULTS: The statistical analysis showed that the at-home bleaching technique did not have a statistically significant effect on the microhardness of any of the restorative materials tested (hybrid, P = .0679; flowable, P = .5088; microhybrid, P = .0601; nanohybrid, P = .6166; ormocer, P = .2154; ceramic, P = .9943). CONCLUSION: At-home bleaching with 15 percent carbamide peroxide did not cause any harmful changes to the microhardness of tooth-colored restorative materials. CLINICAL IMPLICATIONS: Clinicians do not need to replace resin-based composite, ormocer or ceramic restorations after at-home bleaching treatment when the restorations are in posterior teeth.  相似文献   
998.
BACKGROUND: The esthetic replacement of teeth has become an important standard for implant dentistry. While defining this goal has not been difficult, the ability to restore implants esthetically has been fraught with obstacles and sometimes has not been attainable. The purpose of this review is to summarize essential anatomical and surgical considerations for cosmetic implant dentistry. METHODS: This article provides a summary of the predominant findings from clinical studies and case reports that help develop implant surgical guidelines for better esthetic outcomes. RESULTS: Soft- and hard-tissue requirements for placing an implant in an ideal position are defined. The authors discuss the best treatment approaches as well as the limitations associated with esthetic implant placement. They evaluate the available data specifically for the maxillary anterior sextant, since this anatomical region has higher esthetic demands. CONCLUSIONS: Several parameters and various surgical techniques have been developed to manipulate soft- and hard-tissue contours and to control the esthetic outcome for implant-supported restorations. CLINICAL IMPLICATIONS: It is essential for practitioners to understand the anatomical basis for and limitations of implant dentistry in the esthetic zone.  相似文献   
999.
BACKGROUND: The authors present a case that demonstrates the efficient replacement of a fixed prosthesis after a patient's abutment tooth fractured and required extraction. The fractured tooth had a local infection, and the maxillary bone was low-density and limited in height. CASE DESCRIPTION: The authors removed the tooth and grafted the site with particulate bone, while concurrently placing two implants in the edentulous region. After four months, they placed one additional implant and secured a fixed provisional prosthesis within one week. CLINICAL IMPLICATIONS: The patient wanted to minimize the time that she would have to be without a fixed prosthesis. The authors met her expectations by using an accelerated treatment plan.  相似文献   
1000.
BACKGROUND: This study examined the association of knowledge, dental care visits and oral health status with oral health literacy in dental patients. METHODS: The authors administered to adult patients in two private dental offices the short version of the Rapid Estimate of Adult Literacy in Dentistry-30 (REALD-30), a word-recognition test. An interview provided primary predictor variables for REALD-30 and variables that would serve as controls in multivariate logistic regression analyses. RESULTS: About 29 percent of the sample scored below 22 on the 30-point test, a score that the authors defined as a low literacy level. Those with incorrect knowledge (odds ratio [OR] = 5.98; P < .01) and fair-to-poor oral health status (OR = 3.08; P = .06) were more likely to have a low literacy level than were their reference groups. Not having had a dental care visit in the last year was not associated with literacy (OR = 2.26; P = .17). A change from an unfavorable to favorable category for the primary predictor variables would decrease the probability of having a low literacy level by 35 to 61 percent. CONCLUSIONS: A significant number of patients may have a low level of oral health literacy, which possibly interferes with their ability to process and understand oral health information. PRACTICE IMPLICATIONS: Providers should identify patients who are having difficulty understanding and using dental health information and address their needs.  相似文献   
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