INJURIES TO OSSEOUS STRUCTURES
Fracture of Alveolar Process
The extraction of a tooth requires that the surrounding alveolar Done be expanded to allow an unimpeded pathway for tooth. removal. However, in some situations the bone fractures and is removed with the tooth instead of
expanding. The most likely cause of fracture of the alveolar process is the use of excessive force with forceps, which fractures large portions of cortical plate. If the surgeon realizes that excessive force is necessary to remove a
tooth, a soft tissue flap should be elevated and controlled . amounts of bone removed so that the tooth can be easily delivered. If this principle is not adhered to and the dentist continues to use excessive or uncontrolled forcer fracture of the bone will probably occur. The most likely places for. bony fracture are the buccal cortical plate o~er the maxillary canine, the buccal cortical
Prevention of Fracture of Alveolar Process
1. Conduct thorough preoperative clinical and radio graphic examination.
2. Do not use’ excessive force.
3. Use surgical (i.e., open) extraction technique to reduce force required
plate over the maxillary molars (especially the first molar), the portions of the “floor of the maxillary sinus associated with maxillary molars, the maxillary tuberosity, and the labial bone on mandibular incisors (Fig. 11-7). All of these bony injuries are caused by excessive force from the forceps. The primary method of preventing these fractures is to perform a careful preoperative examination of the alveolar process, both clinically and radio graphically (Box 11-5). Surgeons should inspect the root forrnt of the tooth to be removed and assess the proximity of the roots .to the maxillary sinus (Fig. 11-8). They should also check the thickness of the buccal corticalplate overlying the tooth to be extracted lFig. 11-9). If the roots diverge widely, if they lie close to the sinus, or if the patient has a heavy buccal cortical bone, surgeons must take special measures to prevent fracturing excessive portions of bone. Age is a factor to be considered, because the bones. of older patients arc likely to be less elastic and therefore more likely to fracture rather than expand. The surgeon who preoperatively determines that a high probability exists for bone fracture. should consider performing the extraction by the surgical technique·
Using this method the surgeon can remove a smaller
more controlled ‘amount of bone, which results in more rapid healing and a more ideal ridge form for prosthetic reconstruction. When the maxillary molar lies close to the maxillary sinus, surgical exposure of the tooth, with sectioning of the tooth roots into two or three portions, will prevent the removal of a portion of the maxillary smus floor. This prevents the formation of a. chronic oroantral fistula, which requires secondary procedures to close. In summary, prevention of fractures of large portions of the cortical plate depends on preoperative radio graphic and clinical assessment, avoidance of the use of excessive amourits of uncontrolled force, and the early decision to perform an open extraction with removal of controlled amounts of bone and sectioning of multirooted teeth. During a forceps extraction, if the appropriate amount of tooth mobilization does not occur early, then the wise and prudent dentist will alter the treatment plan to the surgical technique instead of pursuing the closed method.
Management of fractures of the alveolar bone takes several different routes, depending on the type and severity of the fracture: If the bone has been completely removed from the tooth socket along with the tooth, it should not be replaced, The surgeon should simply make sure that the soft tissue has been replaced and reposit ionod over there maining bone to prevent delayed healir must also smooth any sharp edges that have caused by the fracture. If such sharp e the surgeon should reflect a small amount )’ and use a bone file to-round off the sharp teeth.
The surgeon who has beeri supporting the alveolar process with the fingers during the extraction will feel the fracture of the buccal cortical plate when it occurs. At this time the bone remains attached’to the periosteum and
will heal if it can be separated from the tooth’ andleft attached to the overlying soft tissue. The surgeon must carefully dissect the bone with its attached associated soft tissue away from the tooth. For this procedure the tooth must be stabilized with the forceps, and a small sharp instrument, such as a Woodson periosteal elevator, should be used to elevate the buccal bone from the tooth root. It is important to realize that if the soft tissue flap is reflected from the bone, the blood supply to the overlying bone will be severed and the bone will then undergo necrosis. Once the bone and’ soft tissue have been elevated from the tooth, the tooth is removed and the bone and soft tissue flap are reapproximated and secured with ·sutures. When treated in this fashion, it is highly probable that the bone will heal in a more favorable ridge form for prosthetic reconstruction than if the bone. had been removed along with the tooth. Therefore it is worth the special effort to dissect the bone from the tooth.
Fracture of Maxillary Tuberosity
tuberosity area is a situation of special concern. The maxillary tuberosity is especially important forthe construction of a stable retentive maxillary denture. If a large portion of this tuberosity is removed along with the maxillary tooth, denture stability. may be compromised. The fracture o f the maxillary tuberosity most commonly results from extraction of an erupted -maxillary third molar or from a second molar if it happen’s to be the last tooth in the arch (Fig. 11-10). ‘ tf this type of fracture occurs during an extraction, treatment is similar to that just discussed for other bony
fractures. The surgeon using finger support for the alveolar process during the fracture (if the bone remains attached to the periosteum) should take extreme measures to ensure the survival of that bony segment. If at all possible the bony segment should be dissected away from the tooth and the tooth removed in the usual fashion. The tuberosity is then stabilized with sutures as previously indicated. However, if the tuberosity is excessively mobile and cannot be dissected.from the tooth, the surgeon has several
options. The first option is to splint the tooth being extracted to adjacent teeth and defer the extraction for 6 to 8 weeks, during which time the bone will heal. The tooth is then extracted with an open surgical technique.
The second option is to section the crown of the tooth from the roots and allow the tuberosity and tooth root section to heal. After 6 to 8 weeks the surgeon can reenter the area and remove the tooth roots in the usual fashion. If the maxillary molar tooth is infected, these two techniqu es should be used with caution. If the maxillary tuberosity is completely separated from the soft tissue, the usual steps are to smooth the sharp
edges of tile remaining bone and to replace and suture the -remaining soft tissue. The surgeon must carefully check for an oroantral communication and treat as necessary,Fractures of the maxillary tuberosity should be viewedas a serious complication. The major therapeutic goal of
management is’ to maintain the fractured bone in place and to provide the best possible environment for healing.This may be a situation that can best-be handled by referral to an oral and maxillofacial surgeon.