Alveolar fractures are more common in the maxillary anterior region, but can also occur in both the maxilla and mandible. Most of them are combined injuries to teeth, alveolar process and surrounding soft tissues.
Surgical anatomy
The alveolar process is the bone tissue that supports and protects the teeth and is divided into maxillary and mandibular alveolar processes. The maxillary alveolar process is adjacent to the floor of the nasal cavity and the floor of the maxillary sinus, and the mandibular bone is thicker and its alveolar process is stronger than that of the maxillary process.
Fracture classification
It can be divided into maxillary alveolar process fracture and mandibular alveolar process fracture.
Fracture causes
Alveolar process fractures are mainly caused by external blows, impacts and falls.
Fracture diagnosis
The diagnosis of alveolar process fracture is not difficult, the history combined with clinical examination and imaging examination can make a clear diagnosis.
1. Medical history
Ask the patient or other witnesses about the nature, size and direction of the injury.
2. Clinical presentation
Alveolar fracture can be linear or comminuted, sometimes it is a simple fracture of the external or internal bone plate, and sometimes it is a complete fracture of a section of alveolar bone. It is often accompanied by tooth damage (tooth fracture or dislocation), as well as soft tissue lacerations. When shaking one tooth in the injured area, several teeth on the fractured alveolar segment move as a whole, which may cause misalignment of the occlusal relationship.
3.Imaging examination
(1) Plain surface tomography film sometimes interferes with the diagnosis due to the occlusion of overlapping images of the cervical vertebrae, and it is best to take additional body cavity films, which can magnify the local fracture of the alveolar process.
(2) CTCT can well show the specific details of alveolar process fracture.
Fracture treatment
The principle of treatment for alveolar process fracture is early repositioning and fixation. Under local anesthesia, the fracture block is repositioned manually, and the displaced and dislocated teeth are also repositioned. Immobilization is performed immediately after repositioning, and the duration of immobilization is usually 4 to 6 weeks. The fixation method should be chosen according to the injury, and the following three methods are commonly used.
1, wire ligature fixation simple linear alveolar bone fracture, the scope of injury is small and no obvious displacement, available wire for simple interdental ligature fixation. A long ligature wire is used around the injured tooth and 2~3 healthy teeth on both sides for encircling ligature, and then a short ligature wire is used for vertical ligature between each two teeth.
2.The arch splinting is suitable for the case where the damage is large and the fracture is displaced. The arch splint is bent into a curved shape consistent with the local arch, and is tightly attached to each tooth surface. Then use 0.25mm diameter stainless steel wire ligature to ligature and fix each tooth with splint together. Alternatively, nylon wires can be ligated and composite resin added around the nylon wires and bonded to form an arch splint fixation. It can also be fixed with orthodontic bracket bonding.
3, palatal brace metal wire arch bar splint elastic traction occurs in the maxillary premolar or molar area of the alveolar process fracture, the fracture segment displaced to the palatal side, when the manual repositioning is unsuccessful, can be made of self-consolidating plastic palatal brace with snap ring, and then the snap ring wire made from the palatal side through the gap to the buccal side of the arch bar shape and bonded to the palatal brace. The displaced fracture segment is ligated with steel wire and bent into a small hook, and then hung on the metal arch bar with a small rubber band for elastic traction reset and fixation.
Postoperative precautions
Postoperatively, antibiotics are used as appropriate according to the injury. Eat soft food and maintain oral hygiene after surgery. Check the damage to the dental nerve in the fracture area. Review 4-6 weeks after surgery and consider whether to remove the fixation device according to the specific situation.