Determination of Shear Bond Strength of Nanocomposite to Porcelain and Metal Alloy

Abstract Objective: To compare porcelain and metal repair done with both nanocomposite and conventional composite. Material and Methods: A total of 30 cylinders were fabricated from Porcelain (I), Porcelain fused to metal (II), and metal (III) substrate each. Control group (A) was bonded with conventional micro-hybrid composite and experimental group (B) was bonded with nanocomposite in a 2 mm thickness. All specimens were thermocycled and stored in distilled water at 37 °C for 7 days. A universal testing machine was used to measure the Shear bond strength (SBS). The difference between bond strengths of the groups was compared using an independent t-test. Results: In all three groups, the SBS was higher in the experimental group as compared to the control group. The use of nanocomposite of metal alloy presented maximum shear bond strength, followed by samples of porcelain fused to metal and finally porcelain, showing the lowest values of SBS. Conclusion: Porcelain and alloys bonded with nanocomposite exhibit enhanced adhesiveness as well as aesthetic and mechanical properties. This subsequently would translate into providing higher clinical serviceability and durability and hence a cost-effective and accessible repair option for human welfare (AU).

Identification of Preferred Learning Style of Medical and Dental Students Using VARK Questionnaire.

Students have unique preferences when it comes to knowledge acquisition, information processing, retention in memory, and recall. This study is aimed at examining the preferred learning styles of medical and dental undergraduate students of Pakistan. It is also aimed at investigating the influence of gender, preclinical or clinical academic year, and academic record on the preferred learning style. A descriptive cross-sectional study was conducted in Pakistan. The learning styles of undergraduate students were identified using visual, aural, read/write, and kinesthetic (VARK) questionnaire. Students were also asked about their satisfaction towards teaching style of their teachers in institute. Descriptive statistics were done to characterize the learning styles of the students. The Fisher test and chi-square test were used to compare the learning preferences between genders and public/private sector students and among preclinical/clinical years. A p value of less than 0.05 was considered significant. A total of 1473 students participated in the study. Among the students, 39.37% preferred unimodal learning style whereas 60.62% preferred multimodal style. Kinesthetic (K) and visual (V) were the most preferred unimodal styles. The preferred learning styles of female students are aural (A), visual (V), and kinesthetic (K), whereas male students preferred visual (V) and kinesthetic more (K). Students with lower academic record chose unimodal styles in comparison to high achievers that chose multimodal styles. Students of clinical year preferred multimodal and quadmodal styles in comparison to preclinical year students. An alarming 78% of students were dissatisfied with their teacher's instructional style. Majority of students prefer multimodal learning styles over unimodal style. Gender, public/private sector, and academic record have influence on the preference of learning styles. Majority of the students are dissatisfied with their teacher's instructional style and rely on social media platforms for understanding. Academics need to adapt their teaching methods according to student preferences in order to get better graduates.