<Li> Displacement of tooth or part of the tooth into the maxillary sinus (upper teeth only). In such cases, the tooth or tooth fragment must almost always be retrieved . In some cases, the sinus cavity can be irrigated with saline (antral lavage) and the tooth fragment may be brought back to the site of the opening through which it entered the sinus, and may be retrievable . At other times, a window must be made into the sinus in the Canine fossa--a procedure referred to as a "Caldwell - Luc". </Li> <Li> Dry - socket (Alveolar osteitis) is a painful phenomenon that most commonly occurs a few days after the removal of mandibular (lower) wisdom teeth . It typically occurs when the blood clot within the healing, tooth extraction site, is disrupted . More likely, alveolar osteitis is a phenomenon of painful inflammation within the empty tooth socket, because of the relatively poor blood supply to this area of the mandible (which explains why dry - socket is usually not experienced in other parts of the jaws). Inflamed alveolar bone, unprotected and exposed to the oral environment after tooth extraction, can become packed with food and debris . A dry - socket typically causes a sharp and sudden increase in pain commencing 2--5 days following the extraction of a mandibular molar, most commonly, the third molar . This is often extremely unpleasant for the patient; the only symptom of dry - socket is pain, which often radiates up and down the head and neck . A dry - socket is not an infection, and is not directly associated with swelling because it occurs entirely within bone--it is a phenomenon of inflammation, within the bony lining, of an empty tooth socket . Because dry - socket is not an infection, the use of antibiotics has no effect on its rate of occurrence . There is some evidence that rinsing with chlorhexidine before or after extraction or placing chlorhexidine gel in the sockets of extracted teeth provides a benefit in preventing dry - socket, but potential adverse effects of chlorhexidine have to be considered . The risk factor for alveolar osteitis can dramatically increase with smoking after an extraction . </Li> <Li> Bone fragments: Particularly when extraction of molars is involved, it is not uncommon for the bones which formerly supported the tooth to shift and in some cases to erupt through the gums, presenting protruding sharp edges which can irritate the tongue and cause discomfort . This is distinguished from a similar phenomenon, where, broken fragments of bone or tooth left over from the extraction can also protrude through the gums . In the latter case, the fragments will usually work their way out on their own . In the former case, the protrusions can either be snipped off by the dentist, or eventually the exposed bone will erode away on its own . </Li> <Li> Trismus: Trismus, also known as lockjaw, affects functions of the oral cavity by restricting opening of the mouth . A double blind, clinical study was done to test the effect of two different medications on post-extraction trismus . The patients who received a corticosteroid by IV had a statistically significant lower level of trismus when compared to patients receiving an NSAID by IV or no medication . </Li>

Is it normal for bone to be exposed after tooth extraction
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