Al-Bayan Journal for Medical and Health Sciences

Relapse is the term used when teeth go back to their original place after orthodontic treatment, so
the success of an orthodontic treatment depends heavily on retention. Retainers, either permanent or
removable ones, are used to avoid relapse. The purpose of this review is to compare the differences
between fixed and removable retainers, and to determine which one works more efficient.

Vitamin C (VC) is considered a powerful antioxidant and enzyme cofactor that is essential in many
biochemical pathways, such as redox reactions and collagen production. Scurvy, a historic disease
that caused a large number of deaths among sailors in the 15th and 18th centuries, resulted from a
clinical shortage of this essential component. The human body is unable to synthesize this material,
so it requires exogenous VC to protect tissue integrity. Nowadays, VC gets a lot of interest due to its
importance for various biological activities. An increasing number of articles study the relationship
between this vitamin and the incidence of serious diseases, along with the progression and recovery
of these diseases. In this review, we explore the effect of deficiency as well as the intake of VC on
cancer prognosis, musculoskeletal injuries, skin care, immunity, infections, Parkinson’s, Alzheimer's,
and psychiatric diseases. We concluded that VC intake could increase survival time in cancer patients,
improve immunity, relieve allergic symptoms, preserve tissue integrity, protect skin from UV harmful
effects, fight skin aging, and improve symptoms in neurodegenerative and psychiatric diseases.

Artificial intelligence (AI) had a renaissance in late 1990s when the expert system
of IBM (Deep Blue), defeated global chess champion Garry Kasparov. Early in the twenty-first
century, the world was startled by the capabilities of powerful AI, such as Alphago and
Watson, which exceeded human capabilities in domains which have been exclusive to humans.
Deep learning (DL) has just made it possible for autonomous cars to operate on public roads
and pass the Turing test, specifying that they are intelligent. AI is being utilized more
frequently in healthcare for automating processes, especially in diagnosis to help physicians
making decisions. Research and studies indicate that, in the opinion of experts, AI applications
might be more beneficial for non-specialists and novices.