What Are Trephine Burs?
Trephine burs are specialized dental instruments commonly used in oral surgery and dental implantology. They are cylindrical or conical in shape, with a hollow center and cutting edges on the circumference. Trephine burs are often used to remove a cylindrical core of bone, which can be advantageous in several procedures and scenarios, including dental implant placement. Here are some of their applications:
Dental Implant Placement: Trephine burs are sometimes used in the initial stage of dental implant site preparation. They can be used to create the initial osteotomy (hole in the bone), especially in cases where precision is critical, such as close to vital structures like the mandibular canal or the maxillary sinus. They can also help to maintain the integrity of the surrounding bone and limit bone heating due to their efficient cutting design.
Bone Grafting: Trephines are often used for autogenous bone harvesting, where a small core of bone is removed from one area of the mouth (usually the mandibular ramus or the chin) to be used as a graft in another area. The hollow design of the trephine bur allows it to capture a cylindrical core of bone, which can then be carefully removed and prepared for grafting.
Implant Removal: In some cases, trephine burs can be used for the removal of a failed dental implant. The trephine is used to cut around the implant, separating it from the surrounding bone and allowing it to be removed with minimal trauma to the bone. This can be particularly useful in cases where the implant has fully osseointegrated but needs to be removed due to peri-implantitis or prosthetic complications.
Biopsy Procedures: Trephine burs can also be used to take a small, cylindrical bone biopsy for histological examination.
Endodontic Surgery: In endodontic surgery, such as apicoectomy procedures, trephine burs can be used to access the root tip with minimal damage to the surrounding bone.
While trephine burs are useful tools, they require careful handling. They should be used under copious irrigation to prevent overheating of the bone, and the pressure applied should be controlled to avoid unnecessary trauma to the bone. Furthermore, due to their design, they can have a tendency to slip or ‘walk’ on the bone surface, and therefore often need to be used in conjunction with a surgical guide or stent for accurate placement.
