Gel is a recent newcomer to the mattress space. It is being used as both a standalone layer and an infusion into foam. Gel benefits mattresses by retaining less heat than memory foam. Also, newer gels compete against memory foam by being more responsive and less toxic.
Gel is similar to foam because it is a polymer made by blending plastics and other chemicals.
Because of gel's heat diffusing properties, it is generally found in the top layer of the mattress under the cover.
Pros: Cooler sleeping surface vs memory foam. More responsive feel when not combined with foam.
Cons: Similar to foam, it is a synthetic blend of chemicals.
Orthopedic is a term that in the context of mattresses means supporting joints, bones, and the overall body. It is commonly used for mattresses that help with spinal alignment and recovery from joint or back issues.
In this way, there is no one material that is certified orthopedic, and the term can be used my manufacturers and marketers to help sell their mattresses.
For this reason, it is important to do additional research on any bed that claims to be orthopedic to make sure that it will actually help straighten the spine and alleviate pain.
Pros: For mattresses that stand true to the name, pain alleviation and better posture are some of the benefits.
Cons: It is difficult to decipher the truth from marketing on orthopedic mattresses.