The dental pins and posts are used to help reinforce the fillings and crowns when a large part of the tooth has been weakened or disappeared. Both pins can be used in the same tooth, if necessary. Every situation is different. The dentist will decide each case based on bolts or studs if needed.
Pins are thin metal shafts that either cemented or are screwed in the tooth. The dental pins provide anchors for a filling or crown. The dentist drilled small holes in the tooth and placement of bolts. Then the filling is built around the pins or crown is placed on top of them. There are various types of fasteners, including tapping, friction and rough pins.
Today, we have new materials that create mechanical and chemical bond to the tooth. For this reason, the bolts are used less frequently. Links help to keep the filling in place. In many cases, this eliminates the need of a dental pin. The tooth shape was also affected if a pin is required. So does the amount of force applied to the tooth when biting. Dental bolts increase the risk of damaging the tooth.
When teeth are decayed and must be restored dentist treated with a filling or filling, but sometimes the decay is extensive and much of the tooth is lost. In such cases, pins and poles are used when simple filling material cannot provide adequate strength to maintain masticatory forces and fractures. The dental pins and posts can be used separately or together as decided by the dentist.
There are many types of bolts available in dentistry. They are basically, thin metal shafts. Or are cemented on teeth after making space for them or screwed into the tooth. Used to force the filling. Firstly the pins are placed on the tooth core constructed above and then placed over the crown.
Indications for dental pin
- As additional aids retention bad teeth or decomposed mutilated
- In teeth with poor prognosis,i.e. endodontic and periodontal involved teeth
- When one or more cusps need to be covered
- It is necessary to increase the strength and shape retention
Types of dental pins
Thru bolts that are inserted into the dentin followed by the placement of the restorative material directly over them.
The three major categories of direct bolts are:
- Cemented bolts between 0.001-0.002 smaller than inch root canals. The difference in diameter provides space for cementation. Less retentive, but practically not generate tension around dentin during or after placement
- Friction bolts – 0001 are larger than the root channels and therefore use the elasticity of the dentine to retain a screw threaded fasteners such as clamping inches. Have better retention bolts cemented but generate tensions in the dentin as cracks or lines
- The threaded bolts are of from 0.0015 to 0.002 inches larger than the channels, and as occurs with friction are also retained by the elasticity of the dentin. They provide maximum retention, but also generate excessive stresses in the form of cracks in the dentin
The four sizes of bolts are:
- Regular 0.031 inches [0.78 mm]
- Minim 0.024 inch [0.61 mm]
- Minikin 0.019 inch [0.48 mm]
- Minutes 0.015 inch [0.38 mm]
Indirect bolts are an integral part of the restoration of the mold. These pins are placed parallel to each other and parallel to the path of insertion of the restoration.
Materials dental bolts
- Stainless steel
- Titanium
- Silver
- Molded gold alloys
- Platinum-palladium
- Platinum-iridium
- Plastic
- Aluminum
- Acrylic
Thumbnail dental bolts
The most suitable locations for bolt holes are the corners of the tooth and are less desirable in the middle of the facial surfaces, lingual, mesial and distal of a tooth.
The dentist will try to place the pins in places that are surrounded by thick optimal dentin and restorative material.
Advantages of Dental bolts
- Offer retention without the need for extensive preparation of tooth structure
- It can increase the resistance to the shape of the tooth preparation a certain extent
- Slower and less expensive than other restorations require multiple appointments
Disadvantages of dental bolts
- Not increase the strength of the material overlying restorative.
- Induce stresses in the dentin in the form of cracks or mania lines, which can increase the potential of fracture of the tooth, micro leak pulp damage etc…
- Enhance the chances of drilling the filling or on the outer surface of the tooth