METHODS: This systematic review was performed conforming to preferred reporting items for systematic review and meta-analysis (PRISMA) model. Four different databases (PubMed, Science Direct, Scopus and Medline databases) as well as manual searching were adopted. Relevant studies from January 2000 till September 2021 were retrieved. Critical Appraisal Skills Programme (CASP) was used to assess the quality of the selected studies.

RESULTS: Out of 755 articles, only 14 which met the eligibility criteria were included. Six studies found that titanium dioxide nanotube (TNT) reduced oxidative stress and promoted osteoblastic activity through its effect on Wnt, mitogen-activated protein kinase (MAPK) and forkhead box protein O1 (FoxO1) signaling pathways. On the other hand, three studies confirmed that titanium dioxide nanoparticles (TiO2NPs) induce oxidative stress, reduce ostegenesis and impair antioxidant defense system as a significant negative correlation was found between decreased SIR3 protein level and increased superoxide (O2 •-). Moreover, five studies proved that titanium implant alloy enhances the generation of ROS and induces cytotoxicity of osteoblast cells via its effect on NOX pathway.

METHODS: A total of 521 students from a public university in East Malaysia were asked to complete the Malay versions of the Suicidal Behaviour Questionnaire-Revised (SBQ-R), the Attitudes Towards Suicide Scale, and the Depression Anxiety Stress Scale.

RESULTS: 197 women and 290 men (mean age, 19.13 years) completed the questionnaires, giving a response rate of 93.4%. The prevalence of high-risk suicidal behaviour (SBQ-R score ≥7) was 23.8%. Suicidal behaviour was positively associated with psychological distress and favourable attitudes towards suicide, and negatively associated with unfavourable attitudes towards suicide. Predictors for suicidal behaviour were psychological distress and favourable attitudes towards suicide ('the ability to understand and accept suicide').

MATERIALS AND METHODS: The solution to the problem was preceded by generation of a geometric CAD model of the device and nozzle for barophoresis, including the nozzle and injector geometry. The Ansys SpaceClaim software package was used to generate the CAD geometry.

RESULTS: When solving the problem of finding the optimal distance from the nozzle to the gum surface, the numerical modeling showed that at a distance of 5 mm, the volume fraction of liquid in the mixture is 18-20%. The mixture actually breaks through the gum, filling 0.8 mm of the gum thickness and spreading symmetrically to the sides at a distance of up to 3 cm, forming a cavity. At a distance of 10 mm from the nozzle to the gum surface, the liquid volume fraction in the mixture close to the gum lies in a narrow range of values of 5 to 7%. The mixture touches the surface of the gums, penetrating slightly - at a distance of 0.30-0.45 mm. At a distance of 15 mm from the nozzle to the gum surface, the volume fraction of liquid in the mixture near the gum lies in the range of 2-5%. The mixture slightly touches the gum surface, getting inside at a distance of up to 0.2 mm, having practically no effect on the gum.