Mandibular Fractures

By Dr. Vishaal Bhat on Friday 30 November 2007 with 0 comments



Blunt impacts of moderate intensity cause just bruises and tearing of the periosteum or formation of subperiosteal hematoma. Providing the intensity of a hit does not cause complete interruption of a bone integrity, dislocation of bone fragments does not happen. Resulting defect thus does not affect the whole width of a bone. A fracture with no dislocation of fragments has its fracture line extended clearly along the whole bone’s width, no shifting or deformation is apparent on its edges (this has to be evaluated from two perpendicular projections). Breakage is narrow, sharp and has no interspersed fragments. Even during a complete bone interruption at children, parts of the bone may remain entangled and unshifted due to a strong and flexible periosteum which stays unharmed (“green stick” fracture). Fractures with fragments dislocation have their edges visibly shifted, the breakage is widened and often contains a tooth root or a retained tooth. Fragments are mutually shifted to sides - ad latus, in angles - ad axim, the bone may also be extended or shortened.

According to the number of fracture lines, fractures can be divided into single, double, triple and multiple. The breakages character may be either multiple or comminuted. If a bone tissue is lost (such as gunshot wounds), a defective fractures occur.

Mechanism of wounds.

The lower jaw’s prominent position makes it a body part exposed to traumas. The most frequent causes of a trauma are direct impacts of objects onto parts of the lower jaw ridge or body (a hit by fist, kick, moving objects etc.). Other causes include an impact of moving head to a solid obstacle (falling, hitting a steering wheel at road accidents etc.). During impacts onto the chin area or sides of the lower mandibular, an indirect fracture of one or both articular processes occurs by transferring an impact force onto them. Parts of the lower jawbone that have reduced thickness due to deposition of retained teeth (wisdom teeth) or by the length of a canine tooth’s root are predisposed locations for fractures.

Category: Oro-Maxillo Facial Surgery Notes

POST COMMENT

0 comments:

Post a Comment