Pulpal response to orthognathic surgery: a long-term radiographic study.

The purpose of this study was to determine if the ischemia associated with orthognathic surgery causes long-term pathologic changes in the pulp similar to those documented after traumatic injuries. A total of 93 patients, 21.9 to 63.9 years of age (mean 38.5 years, SD 9.4), consented to participate in a follow-up study ranging from 4.7 to 15.3 years (mean 8.9 years, SD 2.9) after surgery. LeFort I osteotomy was performed on 42 patients and bilateral sagittal split osteotomies on 76 patients. Full-mouth series of periapical radiographs taken at the time of follow-up were compared with pretreatment and posttreatment panoramic radiographs. The development of pulp canal obliteration was observed more often in the maxillae of patients treated with LeFort I osteotomy than in those without (p < 0.001). No difference was seen in the frequency of maxillae with teeth developing radiographic signs of pulp necrosis between patients treated with and without LeFort I osteotomy. However, a higher proportion of the teeth were affected among the patients treated with osteotomy (p < 0.01). The presence of a restoration or caries was a risk factor for the development of necrosis (p < 0.01). Bilateral sagittal split osteotomies had no apparent effect on long-term pathologic pulpal changes. No internal resorption was seen. Only very few teeth were extracted during the follow-up period.