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51.
PURPOSE: The objective of this outcome study was to compare ferric sulfate pulpotomy (FS) and primary tooth root canal therapy (RCT) on cariously exposed vital pulps of primary molars. METHODS: A total of 291 molars were treated in 130 children--182 molars received FS and 109 received RCT by random selection. RESULTS: At 2-year reassessment, 116 molars (73 FS, 43 RCT) were available for clinical and radiographic examination. There was no clinical evidence of pathosis in 96% of FS and 98% of RCT molars. Two independent pediatric dentists evaluated periapical radiographs of the treated molars. Molars were classified into 1 of 4 outcomes: (1) N--normal treated molar, (2) H--nonpathologic radiographic change present, (3) P(O)--pathologic change present, follow-up in 6 months, and (4) P(X)--pathologic change present, extract immediately. Survival analysis was applied. A good level of agreement between raters was found for molars with outcome P(X) (kappa=0.745). Intrarater reliability was good for molars with outcome P(X) (kappa=0.710). Significantly greater numbers of FS than RCT molars were rated P(X) at the 2-year recall (chi2=5.8; P=.02). No significant difference in survival between the 2 types of vital pulp treatments was detected in log rank tests (P=.22). CONCLUSIONS: Outcomes for FS were poorer than RCT outcomes at 2 years; however, at 2 years, the survival rates were not statistically different.  相似文献   
52.
PURPOSE: The purpose of this project was to establish median eruption ages of primary teeth and evaluate eruption differences between contralateral teeth by gender, ethnicity, and household income. Data was derived from a caries study of preschool children. METHODS: A total of 4,277 white (non-Hispanic) and Hispanic preschool children from Arizona were visually examined for caries and tooth eruption status by 5 examiners between February 1994 and September 1995. Analyses of eruption status were conducted using logistic regression to produce an eruption probability distribution from which median eruption ages for the primary teeth were determined. Possible differences in eruption timing between contralateral teeth by gender, ethnicity, and household income were examined. RESULTS: Eruption status of 1 tooth was significantly predictive of the pair-matched tooth for all pairs. Differences were found for the maxillary central incisor (gender) and the mandibular second molar (ethnicity). Eruption ages did not vary by household income. Median eruption ages for each of the 10 primary teeth are presented. CONCLUSIONS: This study provides contemporary median eruption ages for primary teeth.  相似文献   
53.
A new radiographic technique was used to compare apical transportation in four Ni-Ti rotary instrumentation sequences. Mesiobuccal canals of 60 extracted mandibular molars were randomly divided into four groups. Groups 1 and 3 were instrumented by crown-down and groups 2 and 4 by step-back technique with 0.06 ProFiles series 29 to size 6. In groups 3 and 4 Greater Taper files were first used in a crown-down manner. The central axes of initial and final instruments were radiographically superimposed to measure loss of working length (WL) and transportation at 0, 0.5, 1, 3, and 5 mm from WL. ANOVA test showed no significant differences among groups regarding degree of transportation or loss of WL. Transportation was negatively correlated with radius of curvature at 0.5 and 5 mm from WL. The results indicate that the operational sequence of ProFiles or preinstrumentation with GT files has no effect on degree of transportation and loss of WL.  相似文献   
54.
OBJECTIVES: The aims of this investigation were to evaluate the interests of primary care dental practitioners within the Mersey Postgraduate Deanery in research and their views on research, their experience and research training needs. METHOD: A questionnaire was sent to all practitioners in the Mersey Deanery asking for views on dental research, whether they had been involved in any research projects or had any research training, and whether they would be interested in research training and being part of a primary dental care research network. RESULTS: A total of 192 practitioners from the 1120 in the Mersey Deanery expressed an interest in being involved in primary care research. Most believed that primary care research was very important in providing a stronger evidence-base in dentistry and improved quality of dental care. Over 50% of respondents were interested in collaborative research, provided that their income and time could be protected and it was part of the normal working day. Almost 25% had some research experience and a number had undergone research training, ranging from informal training to part of a degree. CONCLUSIONS: A number of GDPs in the Mersey Deanery are interested in primary care research. With appropriate training, support and recognition within the new Personal Dental Services (PDS) contracts, there is a golden opportunity for more primary care dentists to participate in research. This, in time, will add to the evidence base in dentistry and should improve patient care.  相似文献   
55.
Organizing multiple and varied implant components in preparation for providing treatment for a patient with a complex implant prosthesis can be a challenge to even the most experienced practitioner. The many implant abutment component options available, especially when different sizes and types of abutments will be used in 1 arch, can create confusion for both dentist and assistant, hindering chairside efficiency. This article describes the fabrication and use of a custom chairside implant components organizer.  相似文献   
56.
Letters to the Editor   总被引:1,自引:0,他引:1  
  相似文献   
57.
Lack of access to oral care is a severe problem in the United States with over one-third of the population lacking dental insurance. In this group, 32 million people lack dental insurance and access to public dental services (Medicaid or Medicare), and 7 million of them need dental care. In some high-risk populations, such as Native Americans, two-thirds have unmet dental needs. Only 1 percent of Medicaid-eligible babies have a dental examination before twelve months of age. In this paper the social covenant of the dental profession is examined and suggestions made for improving access to care through improved efficiency. It is proposed that 1) private dentists should accept 5 percent per annum of their patients for indigent care funded by improved efficiency from utilizing allied dental providers (ADP) in new roles, and 2) ADP should have their own independent state boards. If dentists refuse to honor their social covenant, then ADP should be allowed to practice independently, breaking the professional monopoly.  相似文献   
58.
The purpose of this study was to compare the contents of root canals obturated with gutta percha and AH-26 sealer (Dentsply, Tulsa, OK) to canals obturated with the Resilon and Epiphany (Pentron, Wallingford, CT) system. Canal contents were assessed by determining the percentage of canal space occupied by core material, sealer, voids, and debris. Forty extracted human maxillary anterior teeth were instrumented, and the teeth were randomly assigned to either the gutta percha/AH 26 group or the Epiphany/Resilon group. Canals were obturated, and the teeth were subsequently embedded in resin and sectioned horizontally at 2, 4, and 6 mm from the anatomic apex. Sections were photographed by using a low vacuum scanning electron microscope. Image-J (Wayne Rasband; National Institute of Health, Bethesda, MD) software was used to quantify the proportion of core material, sealer, voids, and debris in each canal. Percentages and statistical comparisons for each method were compared. There were no significant differences found among the two groups in terms of the percentage of core (p = 0.9), sealer (p = 0.58), debris (p = 0.999), or voids (p = 1.00). Additionally, there were no differences in the percentage of core material, sealer, debris, or voids at any of the examined levels (2, 4, or 6 mm).  相似文献   
59.
PURPOSE: The purpose of this study was to compare the linear dimensional accuracy and the handling characteristics of 7 die materials. MATERIALS AND METHODS: A master die analogous to a complete veneer crown preparation was machined from medical grade stainless steel, and 3 measurements (1: vertical; 2 and 3: horizontal) were made from 3 scribed reference lines. Individual polyvinylsiloxane impressions were made (n = 10) for each of the specimens. The fabricated dies were measured (50x) to the nearest 0.0001 mm. Data were subject to ANOVA/Duncan tests at significance level 0.05 and pairwise comparisons. RESULTS: Type IV resin-impregnated dental stone and copper-plated dies most closely approximated the dimensions of the master die, and were not significantly different from each other in any of the pairwise comparisons. Conventional Types IV and V dental stone dies exhibited setting expansion within the range appropriate for gypsum. Epoxy resin die materials demonstrated shrinkage comparable to the expansion of the Types IV and V dies. Polyurethane dies displayed a combination of linear expansion and shrinkage. Bis-acryl composite resin dies had excessive shrinkage. CONCLUSIONS: Type IV resin-impregnated dental stone and copper-plated dies were more dimensionally accurate than the other die materials tested.  相似文献   
60.
Background.  Dental caries continues to be the most common infectious disease of childhood; however, it is no longer pandemic, but endemic in specific sectors of populations. Therefore, it is important to identify and target patients at risk of developing caries in order to develop specific preventive measures.
Aim.  This study aims to test dental caries risk indicators for significant associations with caries severity.
Design.  Five separate, small, isolated rural villages in Mexico with varying degrees of caries prevalence were selected for this observational study. A total of 248 children were examined. Risk indicators were assessed via questionnaire and water and salt fluoride analysis. Caries severity was measured by the International Caries Detection and Assessment System (ICDAS-I).
Results.  Prevalence of caries ranged from 95% to 100% for the five villages. Mean total DMFS (decayed, missing, or filled surfaces–permanent teeth) and dmfs (decayed, missing, or filled surfaces–primary teeth) scores ranged from 2.5 to 5.0 and from 11.3 to 16.9, respectively. Multivariable models showed age and drinking soda between meals to be significantly associated with DMFS, and drinking juice and being female were significantly associated with dmfs.
Conclusion.  DMFS and dmfs were high in each village, significantly different between villages, and associated with specific risk indicators.  相似文献   
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