Skeletal stability after maxillary step osteotomy compared with original Le Fort I osteotomy during one-year of follow-up

Comparison study of the Le Fort I osteotomy using 2- and 4-plate fixation

This study was conducted to evaluate the postsurgical stability of Le Fort I osteotomy using zygomatic buttress internal fixation alone with no piriform aperture internal fixation. Patients with maxillary retrognathia and mandibular prognathism underwent the Le Fort I osteotomy with a bilateral sagittal split ramus osteotomy. In group I, fixation was accomplished using titanium plate and screws placed at the piriform aperture and the zygomatic buttress (4 plates). In group II, fixation was accomplished using titanium plate and screws placed at the zygomatic buttress (2 plates). Lateral cephalometric radiographs were taken preoperatively (T1), immediately after surgery (T2), and at 6 months to 1 year (T3) to evaluate skeletal movement. In total, 32 patients were included in this study. None of the patients had wound infection, dehiscence, bone fragment instability, and long-term malocclusion. Regarding point A and the posterior nasal spine (PNS), vertical and horizontal relapse in groups I and II did not differ significantly. In most hospitals, the maxilla was fixed using four plates (piriform aperture and zygomatic buttress); however, within the limitations of the study, the choice of the number of plates for osteosynthesis following Le Fort I osteotomy and repositioning of the maxilla can be left to the discretion of the surgeon without putting the patients at risk for increased relapse by careful intraoperative management.

Evaluation of Related Factors of Maxillary Sinusitis After Le Fort I Osteotomy Based on Computed Tomography: A Retrospective Case-Control Study

ABSTRACT

Maxillary sinusitis is 1 of the postoperative complications of the Le Fort I osteotomy, this study investigated the related factors of maxillary sinusitis after Le Fort I osteotomy. A total of 23 cases, 92 controls, and 11 related factors were included in this case-control study with a 1:4 case-control ratio. The risk factors for maxillary sinusitis after Le Fort I were examined by least absolute shrinkage and selection operator multivariate conditional logistic regression and least absolute shrinkage and selection operator multivariate linear regression. The patency of maxillary sinus ostium at 6 months after surgery was significantly associated with maxillary sinusitis after Le Fort I osteotomy. Compared with the obstructed maxillary sinus ostium, the percentage of the volume of the healthy air cavity in the complete sinus cavity increased 70.7% when the maxillary sinus ostium was unobstructed, and 95% confidence interval was 0.610 to 0.805. Similarly, when the maxillary sinus ostium was wide, the percentage increased 6.0% compared with the narrow 1, and 95% confidence interval was 0.013 to 0.107. This study indicated that the patency of maxillary sinus ostium has an important impact on maxillary sinusitis after Le Fort I osteotomy. Close attention should be paid to maintain the maxillary sinus ostium and the drainage of maxillary sinuses unobstructed in a clinical setting.

A study of unfavorable splits in the sagittal ramus osteotomy with a short lingual cut

In the bilateral sagittal split osteotomy, a short lingual cut is made on the medial side of the ramus; however, in some cases, a true fracture occurs on the buccal side of the ramus. The purpose of this study was to evaluate the relationship between the splitting pattern of the mandible and the form of the mandible, the surgical technique used, and the postoperative occurrence of relapse after 'unfavorable' splits. The investigation examined 143 patients in whom a short lingual cut was attempted. The rate of unfavorable split was 14.7% (42/286). A strong correlation was observed between the reach of the lateral bone cut to the inferior border of the mandible and an unfavorable split. According to multivariate regression, the factors leading to an insufficient lateral bone cut were the degree of inward curvature of the ramus (P=0.001) and the position of the lateral bone cut (P=0.002). There was no significant difference in relapse between cases of unfavorable and normal splits. An unfavorable split does not affect the prognosis of the occlusion, but it is important to confirm the inward curvature of the ramus and set the position of the lateral bone cut adequately to avoid unfavorable splits.