Search

Purpose: The transverse dentoalveolar and skeletal stability of multipiece Le Fort I osteotomies with 3 different techniques was investigated. Materials and Methods: The records of 87 patients undergoing bimaxillary osteotomies with 3-piece Le Fort I osteotomy were evaluated. According to the surgical technique of maxillary expansion, the subjects were divided into 3 groups: unilateral palatal osteotomy (group A), bilateral palatal osteotomy (group B), and unilateral palatal osteotomy with fixation of the palatal vault with a resorbable plate (group C). In group A palatal bone grafts were used in 9 patients. Posterior-anterior cephalograms and dental casts were taken before surgery (T1), immediately after surgery (T2), and after a follow-up of 12 to 15 months (T3). The skeletal base was measured between the intersections of the lateral contour of the maxillary alveolar process and the lower contour of the maxillo-zygomatic process. Dentoalveolar width was measured between the first premolars and the first molars. According to the magnitude of expansion, the groups were divided into the following subgroups: negative (constriction), 0 to 2 mm, greater than 2 mm to 4 mm, and greater than 4 mm. An analysis of variance with Bonferroni correction was used to compare the demographic and treatment characteristics and the surgical and postsurgical transverse movements of the 3 study groups. The paired t test was run to evaluate the surgical changes (T2 − T1) and the postsurgical stability (T3 − T2). The influence of palatal bone grafts and downgrafting of the maxilla on the amount of relapse was investigated with the unpaired t test. Results: The study variables (T1), the surgical changes (T2 − T1), and the postsurgical changes (T3 − T2) showed no significant differences between the 3 study groups. However, a tendency for less relapse in cases with major expansion was seen in group C. The mean expansion of the entire sample was 2.13 mm at the skeletal base, 1.11 mm in the premolar region, and 1.99 mm in the molar region. Mean relapses of 0.20 mm (9%) at the skeletal base, 0.76 mm (68%) in the premolar region, and 1.20 mm (60%) in the molar region were seen. Palatal bone grafts had no significant effect on the postsurgical changes in group A. Anterior and posterior downgrafting did not result in significantly more relapse. Conclusions: Surgical expansion of the maxilla provides stable results at the maxillary skeletal base but high relapse rates in the dentoalveolar area. Preoperative orthodontic expansion is one of the main sources of transverse relapse. Fixation of the palatal vault with resorbable plates is a possible technique to improve transverse stability. Larger samples are necessary to provide statistical significance. [Copyright &y& Elsevier]

Purpose: The aim of the present study was to investigate the effect of segmentation on the stability of Le Fort I osteotomies in bimaxillary procedures. Patients and Methods: One hundred twenty patients undergoing bimaxillary osteotomies (60 single-piece maxilla, 60 3-piece maxilla) were included in the study. Cephalometric analysis was performed before surgery (T1), immediately after surgery (T2), and after a follow-up of 12 to 15 months (T3). The positional changes of 6 angles (angle of nasion-sella line to A point-nasion line, angle of nasion-sella line to B point-nasion line, angle of nasal line [plane] to nasion-sella line, angle of mandibular line [plane] to nasion-sella line, angle of upper incisor to nasion-sella line, angle of lower incisor to mandibular line [plane]) and 4 maxillary landmarks (upper incisor edge, mesial cusp upper first molar, anterior nasal spine, posterior nasal spine) were measured by superimposition of radiographs. Paired t test was run to evaluate surgical changes (T2-T1) and postsurgical stability (T3-T2). Differences between the 1-piece maxilla group and the 3-piece maxilla group were analyzed with 2-tailed t test. Pearson correlation coefficient was calculated to determine relations among the magnitude of maxillary advancement, superior and inferior repositioning and postsurgical changes of angle of nasion-sella line to A point-nasion line, and the respective landmarks. Results: The study variables (T1), surgical changes (T2-T1), and postsurgical changes (T3-T2) showed no significant differences between groups with single-piece and 3-piece maxilla. However, a tendency for more relapse was observed in the 3-piece maxilla group in the vertical direction. A significant inferior movement of the upper molar (mesial cusp upper first molar) was seen in the single-piece maxilla group (0.5 mm) and the 3-piece maxilla group (0.4 mm). In both groups and all directions, the T2-to-T3 changes had no significant correlation with the T1-to-T2 changes. No differences were observed between superior and inferior repositioning. Conclusions: Segmentation of the maxilla does not provoke major skeletal or dental instability and should be considered whenever indicated. Adequate bone grafting provides good stability in anterior and inferior repositioning of the maxilla. [Copyright &y& Elsevier]

Objective: The aim of the present study was to investigate the effect of segmentation and different movements of the segments in LeFort I osteotomies on the bone blood flow (BBF). Material and methods: The study sample of the prospective cohort study was composed of subjects scheduled to undergo 3-piece LeFort I osteotomies and simultaneous BSSO for correction of developmental skeletal deformities. The primary predictor variables were: time (T1, before LeFort I osteotomy; T2, after LeFort I osteotomy; T3, after segmentation and fixation of the maxilla) and magnitude of maxillary movement in the sagittal, vertical, and transverse planes measured in millimeters (mm). The subjects were assigned to 2 risk groups (high/low) depending on the amount of the movement. The primary outcome variable was maxillary bone blood flow measured with a laser Doppler at 4 sites: premaxilla, right and left maxillary lateral segments, and the mandible. Results: No significant difference was observed among the 3 maxillary regions. The mean decrease of the maxillary BBF between T1 and T2 as well as the reduction of BBF between T2 and T3 were statistically significant for all regions (P = .028 to P = .005 for T1/T2; P = .003 to P = .028 for T2/T3). No significant difference could be found between the 2 risk groups of maxillary movements. Conclusions: Multisegmental maxillary osteotomies lead to a significant reduction of BBF. Moderate maxillary movements have no significant influence on the blood supply. [Copyright &y& Elsevier]

Purpose: Autologous blood donation is not routinely recommended for all cases of orthognathic surgery. The aim of this study was to evaluate the factors for blood loss during bimaxillary osteotomies that might indicate preoperative blood donation. Patients and Methods: In a prospective study, 127 consecutive patients undergoing bimaxillary surgery within a 14-month period were examined for hemoglobin and hematocrit reduction. Possible factors for intraoperative blood loss such as operating time, application of hydroxyethyl starch in segmental osteotomies, experience of the surgeon, and additional procedures (genioplasty, malar osteotomy, iliac crest graft) were statistically analyzed. Results: The experience of the surgeon had no influence on the blood loss. Operating time and Quick value correlated significantly with hemoglobin and hematocrit drop after surgery. There was no difference between 1-piece maxilla cases with or without additional procedures and segmental maxilla cases without additional procedures. Only for the group of patients with segmental osteotomies and additional procedures was a significant higher blood loss found. Two patients (1.6%) received 1 unit of blood. Conclusion: For patients undergoing bimaxillary osteotomies with segmentation of the maxilla and additional procedures, a preoperative donation of autologous blood should be considered. [Copyright &y& Elsevier]

We present a case of implant rehabilitation of the mandible in a young patient affected by craniofacial fibrous dysplasia. A computed tomography scan showed involvement of the left orbital contour and left maxilla, with total involvement of the mandible. We performed conservative surgical treatment from 2004 to 2011 to reconstruct and recontour the orbital and mandible region. Next, we performed implant rehabilitation of the mandible. This case emphasizes the importance of conservative and nondemolition treatment to obtain excellent functional and esthetic results. [ABSTRACT FROM AUTHOR]