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991.
OBJECTIVE: This study presents race/ethnic-specific distributions of dental expenditures and their sources of payment by socioeconomic characteristics among US working-age adults. METHODS: Data for persons aged 19-64 years from the 1987 National Medical Expenditure Survey (NMES) (n = 18,696) were used to calculate mean dental expenditures and their 95 percent confidence intervals. RESULTS: Dental expenditures were reported by 44.5 percent of participants. Non-Hispanic whites and persons with higher income were more likely to report dental expenditures than their counterparts. Among persons reporting expenditures, those with lower income had lower expenditures than higher-income persons. No differences in the amount of expenditures by race/ethnicity, sex, or employment status were observed. In all race/ethnic groups almost half the expenditures were paid out-of-pocket and one-third by dental insurance. CONCLUSION: While sociodemographic characteristics determined who had dental expenditures, they did not determine the amount or source of those expenditures. 相似文献
992.
A. J. Smith M. Alexander D. Mackenzie A. Lennon M. P. Riggio T. W. MacFarlane 《Journal of clinical periodontology》1998,25(4):334-339
Abstract. The aim of this cross-sectional study was to investigate the clinical application of chairside tests for gingival crevicular fluid (GCF) aspartale amino-transferase (AST) levels and plaque BANA hydrolysis activity with the presence of the periodontal pathogens Porphyromonas gingivalis and Actinohacillus action-mycetemcomitans. The study comprised 100 periodontitis sites (pocket depths≥4 mm. GI = 3) from 10 patients with chronic adult periodontitis and 100 control sites (pocket depths <4 mm. GI<3) from 10 periodontally healthy patients comprising 55 healthy sites (pocket depths <4 mm. GI=0) and 45 gingivitis sites (pocket depths <4 mm, GI=1 or 2). The values for both BANA hydrolysis and AST levels were significantly higher in samples from periodontitis compared with gingivitis and healthy sites (p<0.001), A. actinomycetemcomitans was identified in 45% and P. gingivalis in 17% of periodontitis sites but neither pathogen was recovered from control sites and there was no significant correlation with (he clinical parameters measured. There was no significant relationship between the presence of P. gingivalis and/or A. actinmycetemcomitans with BANA hydrolysis or AST levels. A significant correlation (p=0.0017) was observed between BANA hydrolysis and pocket depth and between AST hydrolysis and the GI (p=0.01). This study failed to demonstrate a positive association between chairside analysis of GCF metabolites for AST levels and/or BANA hydrolysis with P. gingivalis and A. actinomycetemcomitans. However, the GCF metabolites had a significant correlation with periodontally diseased sites in patients with chronic adult periodontitis and may help confirm clinical observations. 相似文献
993.
Kleier DJ Averbach R 《Compendium of continuing education in dentistry (Jamesburg, N.J. : 1995)》2006,27(2):87-91; quiz 92, 112
The purpose of this study was to evaluate the concept that novice clinicians could perform clinical endodontics better and more efficiently if the stainless steel hand file technique is replaced with a nickel titanium rotary file technique. In phase 1 of the study, every endodontic case performed by 2 groups was evaluated for total treatment time. In phase 2, the mesial roots of mandibular molars were evaluated for radiographic quality of completed obturation. The authors found that when the rotary file technique was substituted for the hand file technique, appointment time for case completion was significantly decreased (P<.001) and overall radiographic quality of mandibular molar mesial root obturation was significantly increased (P=.0009). These results support the hypothesis that novice clinicians can perform endodontic therapy more efficiently when using a nickel titanium rotary file technique. In addition, no differences were noted in the incidence of file fracture when using rotary instruments. 相似文献
994.
Bleaching tetracycline-stained teeth is the most challenging form of tooth lightening. This article reports on 44 subjects who bleached their tetracycline-stained teeth for 6 months using trays with reservoirs overnight in a half-mouth designed study and 2 of 3 different concentrations of carbamide peroxide (10%, 15% or 20%). The subjects were followed for 5 years. The area evaluated was the middle third of the teeth. More than 55% of tooth lightening occurred within 1 month; after 5 years, more than 65% of the maximum tooth whitening remained for all 3 gel concentrations. Tooth whitening can be accomplished with any of the 3 concentrations used. 相似文献
995.
AIM: It is the aim of this paper to consider the dental factors associated with the need for re-intervention on a restoration, such as the tooth position, size of cavity, and restoration material. METHODS: Patients whose data were included in this study were those whose birthdays were included within a set of randomly selected dates, one of which was chosen in each possible year of birth. The restoration records consisted of all those records containing directly placed restorations which related to courses of treatment of patients 18 years or older with last date on the claim form after 31st December 1990, and with date of acceptance after September 1990 and before January 2002. For each tooth treated with a direct restoration the subsequent history of intervention on that tooth was consulted, and the next date of intervention, if any could be found in the extended data set, was obtained. Thus a data set was created of direct restorations with their dates of placement and their dates, if any, of re-intervention. RESULTS: Data for over 80,000 different adult patients were analyzed, of whom 46% were male and 54% female. A total of 503,965 tooth restoration occasions were obtained from the data over a period of eleven years. Single surface amalgam restorations were found to have the longest survival --58% at 10 years, and glass ionomer the shortest 38% at 10 years. Factors which were found to reduce restoration outcome included involvement of the incisal angle in composite restorations--this resulted in a reduction in median survival of around two years--and the placement of pins in a restoration. The presence of a root filling was also found to reduce the survival of restorations in the crown of the root filled tooth. CONCLUSIONS: Small amalgam restorations have longer survival times before re-intervention than large amalgam restorations such as MOD. Composite and glass ionomer restorations perform less well than amalgam restorations. Pin placement and root filling reduce the survival time of restorations. 相似文献
996.
Cohenca N Karni S Eidlitz D Nuni E Moshonov J 《Refu?at ha-peh ?eha-shinayim (1993)》2004,21(2):48-53, 98
Traumatized teeth present a clinical challenge with regard to their diagnosis, treatment plan and prognosis. The injuries to the permanent dentition include crown and root fractures, subluxations, luxations and tooth avulsion. Common complications are pulp necrosis, periapical pathosis and root resorption. This article will describe new clinical modalities for the treatment of avulsed teeth and discuss the rational for their use. 相似文献
997.
OBJECTIVES: The purpose was to evaluate the effect of various Opalescence tooth-whitening products on enamel. METHODS AND MATERIALS: Enamel blocks were exposed to Opalescence PF 10% Carbamide Peroxide (n = 10), Opalescence PF 20% Carbamide Peroxide (n = 10), Opalescence Trèswhite Supreme 10% Hydrogen Peroxide (n = 10) and Opalescence Quick PF 45% Carbamide Peroxide (n = 10) according to the manufacturer's instructions. The control group was enamel blocks (n = 10) kept in artificial saliva. The values were obtained before exposure and after the 14-days treatment period. Enamel blocks were kept in saliva between treatments. Indent marks on enamel blocks were examined using the scanning electron microscope for treatment effects. RESULTS: All four different Opalescence products damaged enamel. The most damage was done when treated for a long period (112 hours). SEM images also showed damage to enamel by all 4 products. Opalescence with 10% and with 20% Carbamide Peroxide showed the highest damage, which also differed significantly (p < 0.05) from the saliva control group (p < 0.05; Tukey-Kramer Multiple comparison test). CONCLUSION: All 4 Opalescence products damaged enamel. Higher damage was done by the 10% carbamide peroxide and 20% carbamide peroxide products because of the much longer exposure period (112 hours in comparison to 7 hours). 相似文献
998.
Polymerization shrinkage of composites bonded to cavity preparations generates stress on the tooth/restoration interface. The purpose of this study was to verify the influence of degree of conversion and speed of polymerization reaction on contraction stress. We prepared experimental composites with different curing rates by varying the concentration of inhibitor (butylated hydroxytoluene). We verified the effect of degree of conversion by submitting one of the composites to different photo-activation times. Contraction stress was monitored for 10 minutes in a tensilometer. Fourier-transformed infrared spectrometry was used for assessment of the degree of conversion. Volumetric shrinkage was determined by means of a mercury dilatometer. Degree of conversion and volumetric shrinkage showed a non-linear relationship with energy density. Degree of conversion showed a pronounced influence on stress. Increased inhibitor concentration reduced curing rate and contraction stress in composites, without compromising the final degree of conversion. 相似文献
999.
Slots J 《Journal of periodontal research》2002,37(5):389-398
BACKGROUND: The recognition over the past 3 decades of microbial specificity in periodontitis has afforded dental practitioners the ability to prevent and treat the disease with a variety of antimicrobial drugs. These include systemic antibiotics, topical antibiotics and topical antiseptics. RESULTS: Systemic antibiotic therapy can be essential in eliminating pathogenic bacteria that invade gingival tissue and in helping control periodontal pathogens residing in various domains of the mouth from where they may translocate to periodontal sites. Frequently used periodontal combination antibiotic therapies are metronidazole-amoxicillin (250-375 mg of each 3 x daily for 8 days) and metronidazole-ciprofloxacin (500 mg of each 2 x daily for 8 days). Microbiological analysis helps determine the optimal antibiotic therapy and effectiveness of treatment. Topical antibiotics that are commercially available as controlled release devices suffer from several potential problems, including insufficient spectrum of antimicrobial activity in some periodontal polymicrobial infections, risks of producing an antibiotic resistant microbiota, and high acquisition costs. Topical antiseptics of relevance in periodontal treatment include 10% povidone-iodine placed subgingivally by a syringe for 5 min, and 0.1% sodium hypochlorite solution applied subgingivally by patients using an irrigation device. CLINICAL IMPLICATIONS: The present paper recommends periodontal treatment that includes a battery of professionally and patient-administered antimicrobial agents (properly prescribed systemic antibiotics, povidone-iodine and sodium hypochlorite subgingival irrigants, and chlorhexidine mouthrinse). Available chemotherapeutics can provide effective, safe, practical and affordable means of controlling subgingival colonization of periodontal pathogens and various types of periodontal disease. 相似文献
1000.
J. A. YATES 《International endodontic journal》1992,25(3):150-157
A retrospective study of 22 root fractures in 21 patients was performed. Ten patients were less than 11 years of age, and boys were involved more often than girls. Ten patients had more than one injured tooth, but there was no case of alveolar fracture. Twenty-one of the teeth were upper central incisors. Only 11 teeth were seen within the first week, so that not all teeth were splinted and not all displaced teeth were repositioned. Long-term clinical and radiographic review showed that loss of vitality of the coronal pulp could not be reliably detected for at least 1 year. No tooth became abscessed or developed a sinus tract, and resorption of bone at the fracture line was observed in only one out of five non-vital teeth. Lack of displacement and placing of a splint increased the chances of the pulp remaining vital and healing of the fracture occurring with hard tissue. Sclerosis of the coronal pulp occurred mainly when healing was by connective tissue. The apical pulp always remained vital, and there was sclerosis of the apical pulp in almost every case. 相似文献