Characteristics of pulpal blood flow levels associated with non-segmented and segmented Le Fort I osteotomy

Objectives. Laser Doppler flowmetry (LDF) is a noninvasive method to assess pulpal blood-flow (PBF). The purpose of this study was (1) to test whether Le Fort I (LF-I) osteotomy may show tooth type -related effects on LDF measurements, and (2) to investigate whether LF-I and tooth type may predict adverse PBF outcomes. Material and methods. PBF was recorded bilaterally in maxillary incisors, canines, and first premolars in a surgical group of patients who underwent a segmented (n = 14) or nonsegmented LF-I osteotomy (n = 12), and in a nonsurgical group of control subjects (n = 12) who did not undergo orthodontic treatment. PBF measurements were made before surgery (session I), and at intervals between 3 and 5 days (session II), and 55 and 59 days after surgery (session III). The nonsurgical control subjects were tested at similar intervals. An adverse outcome was defined as the presence of " PBF reduction of > 40%." Statistical analysis consisted of univariate analysis of variance for repeated measurements. A multiple logistic regression analysis was used to compute the odds ratio for LF-I and tooth type for adverse outcome versus nonadverse outcome. Results. For the LF-I osteotomy study group there was a significant change in PBF values (P = .000). Analysis of session-related measurements revealed a significant difference between session I-and II-related measurements for the canine (P = .004) of the segmented LF-I osteotomy. Significant increase in risk of a session II -related adverse outcome occurred with a nonsegmented (16.6 odds ratio) (P = .009) and segmented LF-I osteotomy (59.2 odds ratio) (P = .000). The odds ratio that a patient with a segmented LF-I osteotomy might belong to the session III -related adverse outcome group was strong (20.6) and significant (P = .007). Conclusions. LF-I osteotomy type proved to be linked to changes in tooth type-related LDF measurements; it was an important prognostic determinant of adverse PBF outcomes.