The effect of printing parameters on the surface characteristics of three-dimensional (3D)-printed denture base resins (DBRs) is neglected. Therefore, this study investigated the effect of printing orientation and post-curing time on the surface roughness and hardness. One conventional heat-polymerized (HP) resin and two 3D-printing resins (NextDent (ND) and ASIGA (AS)) were used to fabricate a total of 250-disc (10 × 2.5 mm) specimens. ND and AS specimens were printed with different orientations (0-, 45-, and 90-degree) and each orientation group was subjected to four post-curing times (30, 60, 90, 120 min). Printed specimens were thermo-cycled (10,000 cycles) followed by the measuring of surface roughness (Profilometer (Ra)) and hardness (a Vickers hardness (VH)). ANOVA and post hoc tests were used for data analysis (α = 0.05) at significant levels. AS and ND showed no significant changes in Ra when compared with HP (p ˃ 0.05), except the 45-degree orientation (AS/90 min and AS/120 min) significantly increased surface roughness (p ˂ 0.001). There was no significant difference in Ra with different orientations and post-curing time for both materials AS and ND (p ˃ 0.05). Compared with HP, 3D-printed DBRs showed low VH values (p ˂ 0.001). For AS, 90-degree orientation showed a significant decrease in VH at 60, 90, and 120 min when compared with 0- and 45-degree orientation (p ˂ 0.001), while ND showed no significant difference in VH with different printing orientations (p ˃ 0.05). The VH of AS and ND improved when increasing post-curing time to 120 min (p ˂ 0.001), and the printing orientations and post-curing time did not affect the Ra of 3D-printed DBRs.

Periodontal and peri-implant soft and hard tissue in diabetic patients have always been a topic of interest for researchers and clinicians alike. Among which, a subtopic that has attracted more attention is the beneficial effect of metformin (MF) on periodontal and peri-implant soft and hard tissue. This review aimed to assess the impact of MF on the periodontal and peri-implant soft- and hard-tissue healing among diabetic patients. Research was conducted using the keywords ‘metformin’, ‘diabetes’, ‘periodontitis’, ‘implant’, and ‘peri-implantitis’ via the Medline (PubMed) and Google Scholar databases. Selected articles were reviewed. A total of 21 articles, discussing the impact on periodontal health (six animal studies, seven clinical studies, and three systematic reviews) and five studies on peri-implant health (four animal studies and one clinical study) were included. All have reported a positive impact of MF on decreasing the inflammatory response, oxidative stress, and ultimate bone loss. Similarly, human studies reported a positive effect of MF on clinical and radiographic parameters compared with controls. Despite systematic reviews reporting heterogeneity among the included studies, MF has shown a positive impact on periodontal health. In animal, clinical studies, and systematic reviews, MF showed a protective impact on periodontal and peri-implant health.

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The purpose of this quasi-experimental study was to determine the effectiveness of Twitter when used in conjunction with a non-traditional type of educational approach referred to as the “flipped classroom method” upon the academic achievement of 12th grade students and their learning motivation towards mathematics. The study used a quantitative approach, and the sample consisted of 48 students. The study was conducted during a three-week period in two public high schools in Abha, Saudi Arabia. The first hypothesis was that the use of Twitter would improve academic performance in mathematics. The second hypothesis was that learning in a flipped classroom via Twitter would lead to an improvement in math performance but that this improvement within the flipped classroom would differ across gender. The third hypothesis was that learning in a flipped classroom via Twitter would lead to more positive attitudes towards mathematics. The findings did not support the first or the second hypotheses; when used in the context of a flipped classroom approach, Twitter, did not improve academic achievement: F(1, 46) = .49, p = .486.  Improvement in academic achievement from pretest to posttest also did not differ across gender; F(1, 44) = .00, p = .963. However, the results did support the third hypothesis; within the flipped classroom, the improvement in motivation was stronger for girls than it was for boys; F(1, 22) = 51.32, p < .001.

The aim of this quantitative study was to investigate the perceptions of Mathematics teachers working in Abha city, Saudi Arabia, toward using IoT in Mathematics classes for students' acquisition and performance. The sample was selected using the simple random sampling technique, and the researcher collected data using a self-developed scale. The analysis revealed that Mathematics teachers' perception of using IoT is high and integrating IoT in the classroom can improve student participation and help them become more skilled. Also, the findings showed that most of the participants in the survey believe that IoT is a field that is well-equipped to operate effectively. The Pearson correlation coefficient showed a strong and positive relationship between teachers' perception of using IoT and students' concept acquisition and academic performance. Owing to the vast range of study implications and its ability to boost students' performance and acquisition of new Mathematical concepts, IoT must be implemented in the classroom.