（单词翻译:单击）
Quadrate - one of the bones which together with the articular bones and the dentary, made/make up a reptile's jaw1. In mammals the quadrate bone is incorporated into the middle ear as the incus.Ramus - the vertical2 part of the mandible which supports the coronoid and the condylar processes.
Recombinant DNA3 - is DNA from a plasmid into which has been inserted a foreign gene4. The plasmid is then introduced into a host cell, often the bacterium5 E.coli. The host cell may then express the foreign gene and secrete6 the desired protein. This process, commonly known as genetic7 engineering, has been used to great effect in synthesising proteins such as insulin and interferon.
Reduced enamel8 epithelium - (REE) the epithelium produced by the combination of the external and internal enamel epithelium. The REE remains9 covering the enamel crown until the tooth erupts when it fuses with the oral epithelium. The REE remaining on the enamel surface becomes the junctional epithelium.
Refined carbohydrates10 - natural carbohydrates from which other bulk such as fibres have been removed. Granulated sugar is a refined form of sugar cane11.
Remineralisation - the replacement12 of mineral salts lost by de-mineralisation of a solid salt.
Remodelling13 - of bone refers to the constant removal by osteoclasts and rebuilding by osteoblasts The mass of bone can be controlled constantly by altering the balance between removal and rebuilding. The shape of a bone can also be altered by removing in one place and building somewhere else, without necessarily changing the total mass of a bone mass.
Repositioning - of a tooth refers to its movement within the entire dentition which involves the remodelling of the tooth socket14. Repositioning of teeth occurs naturally due to continued eruption15 and mesial (or distal) drift.
