Definition
Definition
Bone distraction is a technique used in maxillofacial surgery to increase bone mass.
Generalities
Bone distraction uses a metal device consisting of a screw in a jack allowing the separation of bone fragments obtained after prior surgical section, and between which a progressive synthesis (production) of additional bone tissue takes place (approximately 1 and a half months).
History
Distraction was invented at the beginning of the century, for economic reasons, by a Soviet man who lacked the necessary equipment for bone grafts. This technique is particularly well-suited to the face. Indeed, it requires significant vascularization , which is the case for the face and skull.
Symptoms
Pathophysiology
Distraction applies to different bone abnormalities:
- Agenesis (malformation corresponding to an insufficiency of development) of the condyle from the mandible (rising branch of the upper jaw which articulates with the skull at the level of the temporomandibular joint).
- Craniostenosis (premature welding of the cranial sutures) such as Crouzon disease among others.
- All bone tissue deficiencies of any kind, mainly in the face.
Medical exam
Technical
Bone distraction utilizes the physiological mechanism of bone formation, which is cut in two. A metal device is attached and connects the two cut parts.
- First, the two parts of bone will produce collagen and fibroblasts.
- Then, the collagen organizes into bundles. At this point, the device is activated (using a screw) to separate the two bone parts, and thus stretch these collagen bundles. This stretching period lasts approximately 15 to 20 days (depending on the desired length).
- Then the stretching is stopped to allow theossification, then at the mineralization to be done (the device being held in place).
- The device is removed after one to two months.