Crowns & Bridges
A crown is a restoration that is fabricated in the dental laboratory and sits over the entire tooth to alter its shape, angulation, contour and colour. Some tooth structure is removed from all surfaces of the teeth to make space for the crown. Advances in ceramics have allowed crowns to be fabricated entirely out of porcelain as opposed to having a metal substructure.
This results in a highly aesthetic, very natural looking crown that mimics the natural characteristics of the neighbouring teeth. Crowns do require regular maintenance and it is important to ensure meticulous oral hygiene around the crown as tooth decay is the primary cause of crown failure.
Crowns can also be used to replace missing teeth in the form of a bridge. In this situation a crown on one tooth is used to support a false tooth beside it. This fills a space (formed by a missing natural tooth) with a permanently fixed false tooth that feels just like a natural one. In some instances a bonded bridge can be used whereby a metal wing is glued to the back of a natural tooth and this is used to support a false tooth. This has the advantage of requiring no preparation of (and consequently no removal of) strong tooth tissue from the natural tooth.
Implants are a very successful and long term treatment that can be used to replace any number of teeth. Placing an implant involves a surgical procedure performed by a specialist oral surgeon or periodontist (gum specialist) during which a titanium screw (implant) is inserted into the bone of the jaw to act as a false root. The implant is accepted readily by the body tissue and becomes integrated firmly into bone. A further surgical procedure is then carried out once the implant has integrated to expose the surface of the implant. A standard crown is then either cemented or screwed onto the implant. Implants can also be used to retain lower removable dentures and they act as strong anchors in these cases.