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The aim of the study was to evaluate the clinical performance of the nanofiller resin composite Filtek Supreme (3M ESPE) vs the conventional fine hybrid resin composite Tetric Ceram (Ivoclar Vivadent) in stress-bearing posterior cavities. In accordance with a split mouth study design, 50 patients (35.7+/-11.3 years) received at least one pair of Filtek Supreme and Tetric Ceram restorations in each of two comparable class II cavities. To obtain comparability, the adhesive Scotchbond 1 was used for all the restorations. After 2 years, the restorations (total number 112) were scored according to the Ryge criteria. After 2 years (recall rate 100%), the results (%) of the Ryge evaluation for the two groups Filtek Supreme/Tetric Ceram were marginal adaptation: Alfa 96/96, Bravo 2/2, Charlie 2/0, and Delta 0/2; anatomic form: Alfa 98/98, Bravo 0/0, and Charlie 2/2; secondary caries: Alfa 100/100 and Bravo 0/0; marginal discoloration: Alfa 98/100, Bravo 2/0, and Charlie 0/0; surface: Romeo 95/95, Sierra 4/4, Tango 0/0, and Victor 2/2; and color match: Oscar 46/57, Alfa 50/39, Bravo 2/4, and Charlie 2/0. One Tetric Ceram and one Filtek Supreme restoration showed fractures that needed restorative intervention. No severe postoperative sensitivities were reported within the observation period. All restored teeth remained vital; the integrity of all the teeth was scored Alfa. After 2 years, no statistically significant differences (Wilcoxon-Mann-Whitney test) was found between the two restorative materials investigated. Therefore, Filtek Supreme, based on a new nanofiller technology, has proved efficaciousness for clinical use in stress-bearing posterior cavities.

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Teaching Electronic Instrumentation to both resident and distant students in biological and engineering sciences using television presents interesting challenges for instruction. Hands-on laboratory experiences are especially difficult. However, a good laboratory experience not only considers basic principles of instruments, transducers, and sensors, but introduces modern applications and examples. This paper reports results of a televised class originating from the Department of Biological Systems Engineering at the University of Nebraska (UNL) during the Fall 1994 and 1995 semesters. In 1995, twenty-four lectures and nine laboratories were produced using multimedia techniques and video taped for continuing education students in Nebraska and resident students at the Department of Agricultural and Biological Engineering, Pennsylvania State University. Twenty-three resident students on campus also participated in the class. Lectures included theoretical and practical concepts, in-class demonstrations, and reading materials. An extensive interactive lecture guide (an incomplete set of notes) was made available to all students. Laboratories included programming of a micro controller for data acquisition and control, building an instrumentation amplifier, strain-gages, differential transformers, thermocouples, flow measurement and optical sensing devices. Some labs evolved out of an inexpensive kit of electronic components for distant students. Others labs were videotaped, with data collection provided on video. Written reports were prepared by the students. Students purchased Windows-based virtual electronics software for designing and testing electronic circuits. A open-ended design project of a team of 2-3 students was required. Each team prepared oral and written reports of their projects. Student interaction was carried out through telephone office hours, E-mail and FAX.