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41.
MB2 in maxillary second molar.   总被引:1,自引:0,他引:1  
Occurrence of the second mesiobuccal canal (MB2) is a frequent finding. Literary reports have shown it to be found more in the cases of the maxillary first molar. However the maxillary second molars have also been found with this variation in a number of canals. This paper presents a case report on the occurrence of a second mesiobuccal canal or the MB2 in the maxillary second molar.  相似文献   
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The purpose of the present investigation was to gather information on the prevalence of dental caries and the quality of restorations of new immigrants to Israel, and to compare those two categories among immigrants from different regions of origin. New immigrants, residents of four absorption centers in Israel, were included in the study. Altogether, 1,031 immigrants (417 Eastern European, 338 Western European/North American and 276 South American) were examined. The results indicate that new immigrants to Israel from Eastern Europe are affected with more carious teeth (D), are missing more teeth (M), and have received quantitatively less treatment (F) than immigrants from Western Europe/North American and South America. The South America are an intermediate group. A similar distribution was found between the groups by their respective ages. The quality of dental restoration was found to be statistically higher among immigrants from Western European/North American and South American origins with the latter group exhibiting an intermediate level of quality of dental restorations.  相似文献   
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OBJECTIVE: This investigation evaluated polymerization shrinkage and depth of cure of five packable composites. METHOD AND MATERIALS: Five materials were used for the investigation: Alert, Surefil, Solitaire, P60, and Prodigy Condensable. Groups of 10 specimens of each material were made measuring either 2 or 5 mm in thickness, mounted in a testing jig, and polymerized using a dental curing light. Linear shrinkage was recorded and converted to a volumetric value. To evaluate depth of cure, ten specimens of each material were fabricated in both 2- and 5-mm thicknesses, and a Knoop hardness number was recorded on the top and bottom surfaces 5 minutes after light curing. A one-way analysis of variance statistical test was used to determine if there was a significant difference among materials. A Tukey multiple comparison test was then used to determine where significant differences existed. RESULTS: The volumetric shrinkage for the 2-mm-thick specimens from highest shrinkage to lowest were: Solitaire (3.3%), Prodigy Condensable (1.8%), Surefil (1.4%), P60 (1.2%), and Alert (0.2%). The 5-mm-thick specimens were ranked as follows: Solitaire (2.1%), Prodigy Condensable (1.0%), P60 (0.9%), Surefil (0.8%), and Alert (0.3%). Hardness for the bottom surface of the 2-mm-thick specimens showed that P60 (48.5) and Alert (42.6) had the highest values. Solitaire (11.2) had a significantly lower value. Hardness for the bottom surface at 5-mm thickness showed Alert (16.5) and P60 (16.3) with higher values than Surefil (8.9). CONCLUSION: Solitaire had the most shrinkage and Alert the least at both 2- and 5-mm depths. Depth of cure was severely compromised for all materials at 5 mm.  相似文献   
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India, a developing country, faces many challenges in rendering oral health needs. The majority of Indian population resides in rural areas of which more than 40% constitute children. The purpose of this study was to assess the oral health status of 5 years and 12 years school going children in Chennai city. The study population consisted of 1200 school children of both the sexes (600 private and 600 corporation school children) in 30 schools, which had been selected randomly. The survey is based on WHO, 1999 Oral Health Assessment, which has been modified by including gingival assessment, enamel opacities/ hypoplasia for 5 years. Evaluation of the oral health status of these children revealed, dental caries is the most prevalent disease affecting permanent teeth, more than primary teeth and more in corporation than in private schools, thereby, correlating with the socioeconomic status. It may be concluded that the greatest need of dental health education is at an early age including proper instruction of oral hygiene practices and school based preventive programs, which would help in improving preventive dental behaviour and attitude which is beneficial for life time.  相似文献   
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