Pathologic jaw fracture is a significant local consequence of chronic periodontal disease.1,2 These fractures typically occur in the mandible due to chronic periodontal tissue loss, which weakens the bone in affected areas.3 Although these fractures can occur in any area of the mandible, they are especially common near the canine and first molar teeth.4 Pathologic jaw fractures are more common in small-breed dogs as compared with large-breed dogs due to their mandibular first molars being larger in proportion to the mandible itself.5 Small-breed dogs also have a minimal amount of bone apical to the tooth root, putting this area at high risk for fracture when apical bone loss occurs.6
Pathologic jaw fractures have a guarded prognosis due to the lack of remaining bone and poor bone quality, presence of infection, low oxygen tension in the area of the fracture, and difficulty in rigid fixation of the caudal mandible.4,6 Regardless of the method of fixation used, diseased root(s) must be extracted to facilitate healing.3,7
Pathologic jaw fractures typically occur as a result of mild trauma but can also occur during dental extraction procedures (ie, iatrogenic fracture).4 Clinical awareness can help reduce risk for iatrogenic fractures during at-risk dental procedures (eg, extraction of the mandibular canines in dogs and cats, the mandibular first molars in small-breed dogs, the mandibular fourth premolars in small-breed brachycephalic animals, and teeth in any area weakened by infection or neoplasia).6
Dental radiography is critical to the proper care of dental patients, as radiography can help identify risk factors for jaw fracture (eg, alveolar bone loss).7 In cases in which severe alveolar bone loss is noted, particularly if the mandibular canine or first molar is affected, owners should be informed of the possibility of iatrogenic jaw fracture prior to extraction of the offending tooth.3,4
Regardless of the degree of bone loss, diseased teeth with minimal remaining bone can be successfully extracted using proper technique.
Multirooted teeth should always be sectioned prior to extraction. This is important because roots of most multirooted teeth are divergent, and thus root tips will break if extractions are attempted in one piece.3,7-11 Root fracture can occur even if a tooth is relatively mobile. In addition, buccal bone removal may be performed if indicated, particularly if one of the roots or part of the root has significant periodontal attachment.8
This patient was successfully managed with a single interfragmentary wire on each side. This technique was elected because it was possible to achieve very good anatomic reduction of the fractures and provide clinically acceptable stability. However, when intraosseous wires are employed to fix fractures of the body of the mandible, it is important to ensure neutralization of bending forces with tension-band wire along the alveolar margin of the mandible and avoid tooth roots. A second area of fixation can also be considered at the ventral mandibular margin with a stabilization wire, which neutralizes rotational and shear forces. This will allow proper biomechanics for healing and prevent movement during the healing period.11