In fact, it is the reconstruction inserted inside the root after the root canal treatment. The majority of the teeth that needs root canal are quite deteriorated and in bad condition which requires a giant filling without the anchorage in the root of the tooth, its possibilities of survival are very low, unlike a tooth that has not root canal treatment.
There are two types of post 1) that are performed in the clinic in a one appointment called “immediate, prefabricated or direct post ” and 2) the one that is performed indirectly and is done in two appointments and are called “cast post prepared in the laboratory. “
Immediate prefabricated or direct post: This is a large reconstruction performed at the dental clinic in one session. After the partial removal of the sealing material from the root canal, it is inserted, after being cemented and filled with reconstruction material, restoring the shape and function of the tooth.
There are several types of immediate post used in dentistry
Screw-shaped metal post, can be made of basic metal and gold colored or titanium metal. The use of these had caused many cracks and fractures of the root of the tooth causing extraction of the tooth, even when the tooth was crowned probably the cause is an excess screwing the screw. Therefore, the recommendation today is not to screw and place it only passively, and to cement it to hold it. Advantages: Very cheap less than 2 dollars, due to this, the use is still common in public clinics such as KUPAT HOLIM and the army. Disadvantages: the golden colored screw causes with the filling material amalgam corrosion in the root and failure of the root canal treatment, therefore it is recommendable to avoid as much as possible its use, also the lack of adaptation to the anatomy of the root walls, not prevent teeth from fracturing no matter what filler material has been used. Therefore, its use is not recommended today as there are excellent substitutes for the same purpose.
plastic or zirconia post without thread, can be transparent or white. In fact, it is smoother and there is no need to screw and it has come up as a better solution to the screw post due to the damage it caused. This type of post is cemented and then the reconstruction is completed with white material. Due to its high price, more than 10 times the price of the screw has caused increase in cost of the treatment and this is economically impossible in the public clinics. Advantages The percentage of failures due to root fractures decreased to levels lower than 10%. White or transparent color is very aesthetic to the tooth. Disadvantages Its price is much more expensive. Requires greater remove of tissue of the root walls that further weakens the tooth (preparation similar to the screw post) inadaptability to canal walls filled with cements without forming an integral part of the tooth.
Resin post reinforced with quartz fiber, the material is transparent and flexible allowing adaptation to the length and width of the canal root resulting in completing and forming an integral part of the root canal. After preparing the walls of the canal with bonding connecting material is inserted together with the filler material that is white and the resin post and a light curing lamp is applied that hardens the material forming a single unit and adapted to the canal as an integral part of the tooth.
Advantages: Unbelievable research results showed that these resin post restore flexibility to the tooth it has lost after root canal treatment. Another advantage is the significant increase in tooth resistance against fractures. Even when the tooth is not crowned. The material is esthetic, better adapted to the shape of the root canal, does not require removal of root tissue, only partial elimination of sealing material and filling of root canal treatment. The possibility of passing through the resin post in order to retreatment in case of failure unlike the other post that need their total evacuation to perform a retreatment. Disadvantages are very expensive, which is reflected in the final cost for the patient impossible for public clinics for its cost but is the best post for its biomechanics qualities to the tooth. A technique that requires more time for its implementation.
Cast post. This post is solid and manufactured in the laboratory requires, therefore, two sessions. In the first appointment, an exact impression of the canal is taken and sent to the laboratory. The impression is transferred to the cast and cast with a metallic alloy (usually not precious), and in the second meeting, the adaptation is checked and the post is cemented to the tooth
Generally, cast post is made when the tooth is completely destroyed and the remaining coronary tissue is minimal. Its cost is greater due to the time and cost of the laboratory unlike of the prefabricated immediate post. Advantages: Restoration possibility and excellent adaptation to the root canal and to the crown of the damaged tooth. A unique mold in which the impression was taken and cannot adapt to another tooth. Disadvantages: Requires two sessions and higher cost due to laboratory factor. After making a cast post the tooth is ready to continue the treatment to receive the crown.