Removal of osteosynthesis material because of symptoms after Le Fort I osteotomy: A retrospective study of 158 patients.

The aim of this study was to analyse the incidence of removal of MESH plates because of symptoms after Le Fort I osteotomy (LF1). The medical files of patients treated with LF1 were retrospectively reviewed. The occurrence of MESH plate removal, indication for removal and time between insertion and removal were noted. The medical literature was reviewed to quantify the reported incidences of removal of titanium osteosynthesis material after LF1. A total of 158 patients were included in this study. LF1 was performed and fixed with MESH plates in 150 patients. Alternative fixation with Champy plates was used in eight patients. Three patients (2.0%) required removal of MESH plates. Seven out of 600 plates (1.2%) were removed. Reasons for removal were tenderness/pain (1), recurrent intraoral infections (1) and a nasal septum deviation correction following the LF1 (1). No statistically significant association was found with the patients' sex or age. In the literature, the reported rates of removal of titanium Champy plates range from 1.5% to 9.5% per site. This study reports a low incidence of symptomatic removal of MESH plates after Le Fort I osteotomy of 1.2% per site, which indicates an important benefit of fixation with MESH plates.

Influence of inferior border cut on lingual fracture pattern during bilateral sagittal split osteotomy with splitter and separators: A prospective observational study.

Bilateral sagittal split osteotomy (BSSO) is a widely used orthognathic surgery technique. This prospective observational study investigated the correspondence between the planned inferior border cut and the actually executed inferior border cut during BSSO. The influence of the inferior border cut on lingual fracture patterns was also analyzed. Postoperative cone beam computed tomography (CBCT) scans of 41 patients, representing 82 sagittal split osteotomies, were investigated. The inferior border cut was intended to penetrate completely through the caudal cortex. Descriptive statistics were used to analyze the executed inferior border cuts. Mixed models were used to investigate the influence of independent variables such as the surgeon's experience on the inferior border cut. Secondarily the influence of the inferior border cut on lingual fracture patterns and the incidence of bad splits was assessed. The inferior border cut reached the caudal cortex in all cases, but reached the lingual cortex in only 38% of the splits. There was no significant relationship between the inferior border cut and a specific lingual fracture line. In this study, postoperative CBCT analysis revealed that the bone cuts during BSSO were often not placed exactly as planned. No significant relationship between the inferior border cut and lingual fracture patterns or bad splits was, however, detected.

Risk factors for common complications associated with bilateral sagittal split osteotomy: A literature review and meta-analysis.

The most common complications that are associated with bilateral sagittal split osteotomy are: bad splits, postoperative infection, removal of osteosynthesis material, and neurosensory disturbances of the lower lip. Particularly in elective orthognathic surgery, it is important that surgeons inform their patients about the risk of these complications and attempt to minimize these risks. The purpose of this literature review and meta-analysis is to provide an overview of these common complications and their risk factors. After a systematic electronic database search, 59 studies were identified and included in this review. For each complication, a pooled mean incidence was computed. Both the pooled study group and the pooled 'complication group' were analysed. The mean incidences for bad split (2.3% per SSO), postoperative infection (9.6% per patient), removal of the osteosynthesis material (11.2% per patient), and neurosensory disturbances of the lower lip (33.9% per patient) are reported. Regularly reported risk factors for complications were the patient's age, smoking habits, presence of third molars, the surgical technique and type of osteosynthesis material. This information may help the surgeon to minimize the risk of these complications and inform the patient about the risks of complications associated with bilateral sagittal split osteotomy.

Angled Osteotomy Design Aimed to Influence the Lingual Fracture Line in Bilateral Sagittal Split Osteotomy: A Human Cadaveric Study.

PURPOSE: The traditional osteotomy design in the bilateral sagittal split osteotomy includes a horizontal lingual bone cut, a connecting sagittal bone cut, and a vertical buccal bone cut perpendicular to the inferior mandibular cortex. The buccal bone cut extends as an inferior border cut into the lingual cortex. This study investigated a modified osteotomy design including an angled oblique buccal bone cut that extended as a posteriorly aimed inferior border cut near the masseteric tuberosity. MATERIALS AND METHODS: The authors implemented a randomized controlled study. The study sample was comprised of 28 cadaveric dentulous mandibles. The primary outcome variable was the pattern of lingual fracture induced using the conventional (n = 14) and modified (n = 14) osteotomy designs. The secondary outcome variables included the incidence of bad splits and the status of the inferior alveolar nerve (IAN). Descriptive and bivariate statistics were computed. RESULTS: The angled osteotomy design resulted in a significantly larger number of the lingual fractures originating from the inferior border cut (odds ratio [OR] = 1.54; 95% confidence interval [CI], 1.27-1.86; P < .01), with a significantly more posterior relation of the fracture line to the mandibular canal (OR = 2.11; 95% CI, 1.22-3.63; P < .01) and foramen (OR = 1.99; 95% CI, 1.28-3.08; P < .01). No bad splits occurred with the angled design, whereas 3 bad splits occurred with the conventional design, although this difference was not statistically significant (OR = 1.11; 95% CI, 0.99-1.25; P = .07). IAN status was comparable between designs, although the nerve more frequently required manipulation from the proximal mandibular segment when the conventional design was used (OR = 1.21; 95% CI, 0.99-1.47; P = .06). CONCLUSION: The results suggest that the angled osteotomy design promotes a more posterior lingual fracture originating from the inferior border cut and a trend was apparent that this also might decrease the incidence of bad splits and IAN entrapment. These results must be carefully extrapolated to the clinical setting, with future studies clarifying these findings.

Investigation of the influence of mallet and chisel techniques on the lingual fracture line and comparison with the use of splitter and separators during sagittal split osteotomy in cadaveric pig mandibles.

In bilateral sagittal split osteotomy the proximal and distal segments of the mandible are traditionally separated using chisels. Modern modifications include prying and spreading the segments with splitters. This study investigates the lingual fracture patterns and status of the nerve after sagittal split osteotomy (SSO) using the traditional chisel technique and compares these results with earlier studies using the splitter technique. Lingual fractures after SSO in cadaveric pig mandibles were analysed using a lingual split scale and split scoring system. Iatrogenic damage to the inferior alveolar nerve was assessed. Fractures started through the caudal cortex more frequently in the chisel group. This group showed more posterior lingual fractures, although this difference was not statistically significant. Nerve damage was present in three cases in the chisel group, but was not observed in the splitter group. A trend was apparent, that SSO using the chisel technique instead of the splitter technique resulted in more posterior lingual fracture lines, although this difference was not statistically significant. Both techniques resulted in reliable lingual fracture patterns. Splitting without chisels could prevent nerve damage, therefore we propose a spreading and prying technique with splitter and separators. However, caution should be exercised when extrapolating these results to the clinic.

Removal of bicortical screws and other osteosynthesis material that caused symptoms after bilateral sagittal split osteotomy: a retrospective study of 251 patients, and review of published papers.

Rigid fixation with either bicortical screws or miniplates is the current standard way to stabilise the mandibular segments after bilateral sagittal split osteotomy (BSSO). Both techniques are widely used and the superiority of one or other method is still debatable. One complication of rigid fixation is the need to remove the osteosynthesis material because of associated complaints. The main aim of this retrospective study was to analyse how often we needed to remove bicortical screws because they caused symptoms after BSSO in our clinic. Review of other published papers also enabled us to investigate the reported rates of removal of screws and miniplates at other centres. The mean (SD) duration of follow-up of 251 patients (502 sites) was 432 (172) days, and the number of bicortical screws removed in our clinic was 14/486 sites (3%). Other methods of fixation were used at 16 sites. We found no significant association between removal of bicortical screws and age, sex, presence of third molars, or bad splits. Published rates of removal of bicortical screws and miniplates are 3.1%-7.2% and 6.6%-22.2% per site, respectively. These findings show that fixation with bicortical screws after BSSO is associated with a low rate of removal of osteosynthesis material. Reported incidences imply a lower rate of removal for screws than for miniplates.