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The durability of bonding efficacy of composites with hard tissues of a tooth was investigated at application of one-bottle adhesive with total etching and five self-etching adhesives. The efficiency of etching by 36% orthophosphoric acid and acid components of self-etching adhesives was estimated. The adhesion between substrate and composite was measured by method of microtensile bond strength (mTBS). The control of efficiency of etching and depth of the penetration was carried out with the confocal laser scanning microscopy. It was established, that self-etching adhesives are capable to guarantee bonding of composites with enamel and dentine at a level compared with adhesives of the 5th generation. Deep adhesives penetration in dentine tubules is not the key factor for creation of reliable bonding. 相似文献
998.
Koerber A Graumlich S Punwani IC Berbaum ML Burns JL Levy SR Cowell JM Flay BR 《Pediatric dentistry》2006,28(6):524-530
PURPOSE: The purpose of this study was to examine tooth-brushing frequency in 575 urban and nearby suburban African American children as part of a comprehensive risk-reduction study for students at high risk for violence, drugs, school delinquency, and unsafe sexual behaviors to determine which covariates predicted tooth-brushing frequency. METHODS: Students were surveyed 5 times, from the beginning of grade 5 and the end of each year through grade 8, and parents were surveyed at the beginning of grade 5. Peer influence, importance of being liked, self-esteem, attitudes towards tooth-brushing, oral health knowledge, self-efficacy, parental attitudes, and other covariates were examined for the ability to predict self-reporting of tooth-brushing frequency. RESULTS: In the fifth grade, peer influence, the importance of being liked, and physical self-esteem were the significant predictors, and peer influence continued to predict tooth-brushing in the eighth grade. Oral health knowledge and parental influence were not significant. CONCLUSION: Peer influence is an important factor in tooth-brushing behavior in metropolitan African American preadolescent children. 相似文献
999.
van der Waal RI Huijgens PC van der Valk P van der Waal I 《International journal of oral and maxillofacial surgery》2005,34(4):391-395
Non-Hodgkin lymphomas (NHLs) are often present outside the lymph nodes. Although primary extranodal NHLs (PE-NHL) form a substantial part of all NHLs, reports on oral PE-NHLs are rare. Forty patients with PE-NHL of the oral cavity have been studied for the distribution of gender, age, oral subsite and presenting complaint, histological subtype according to the WHO classification, clinical stage, treatment, and follow-up. The data are reviewed against the background of the literature. Furthermore, the International Prognostic Index has been taken into consideration. All patients had a lymphoma of B-cell lineage. Two-thirds of patients presented with locoregional disease. Mean survival time was 38 months, with a mean recurrence-free survival time of 31 months. There was no statistically significant difference in survival time between patients with bone versus soft tissue localisation of the PE-NHL. In view of the rarity of PE-NHL involving the oral region multicenter studies are needed for evaluation of the usefulness of the International Prognostic Index for non-Hodgkin lymphoma in this particular part of the body. 相似文献
1000.
R M Block R D Lewis J B Sheats S G Burke 《Oral surgery, oral medicine, and oral pathology》1978,45(2):282-292
After pulpal extirpation of twenty teeth in each of five dogs, these animals were primarily immunized intramuscularly by combining formocresol with the dog's own pulp (three dogs), saline solution with pulp (one dog) and injecting sheep erythrocytes (one dog). A sixth dog was used as a control for the Arthus skin test. Secondary immunizations were accomplished via the root canal every 7 days over a 28-day period. Arthus skin-test reactions demonstrated less of a response to the formocresol alone than when the dogs' pulp was conbined with this material. In vitro analysis of hemagglutinating antibody titer showed a tremendous increase when pulp was incubated with formocresol as compared to the saline-treated pulp. Therefore, dogs' pulp tissue became antigenically altered by the formocresol recognized by the host, and a specific humoral response resulted. 相似文献