A post and core is a prosthetic device that is utilized when there is inadequate tooth structure remaining to support a traditional restoration or an artificial crown.
The post is a small rod, usually metal, that is inserted into the root space of the tooth and protrudes from the root a couple of millimetres. The post is then used to hold the core, or a filling in place.
Because the post is inserted into the root canal, a post and core can only be made for a tooth that has had root canal treatment.
The core replaces missing tooth structure in preparation for making a new dental crown. Normally, a dental core can be directly built up from composite materials without a post to hold it in place.
However, a dental post can be used to help to anchor the core to the tooth. In this case, the core is generally made off metal alloys and the device is called post and core.
The core is then utilized to hold a dental crown in place. The crown can be a single unit crown or a retainer crown for a dental bridge.
A great deal of a dental crown stability depends on the amount of tooth structure that extends into its interior. If very little tooth structure occupies this space, the crown will be easily dislodged, especially by forces directed at its side.
Basically, the core is rebuilding the tooth so it is closer to its original dimensions. Hence, the crown's stability will greatly increase, and therefore its long-term chances for success are maximized. after : post and core will increase crown's stability
A post and core is indicated when a large part (or all) of a tooth's original crown structure has been lost. The crown structure can be damaged either due to the progression of dental decays or because of a tooth trauma.
A post and core can only be manufactured if the tooth has had root canal treatment. After the endodontic procedure has been completed, some of the root canal filling is removed from the canal space to place the post.
As a rule of thumb, if more than half of a tooth's original crown portion has been lost, a post is needed to assist in anchoring the core to the tooth. If more than half still remains, itself (which basically means a direct build up with composite materials) will probably suffice.