What Is the Incidence of Implant Malpositioning and Revision Surgery After Orbital Repair?

PURPOSE: Postoperative radiographic examinations are the gold standard in maxillofacial surgery, except in orbital reconstruction. Therefore, the purpose of this study was to estimate the frequency of implant malposition and revision operation after orbital repair. MATERIALS AND METHODS: This retrospective cohort study was conducted in a level I trauma center at the University Hospital in Bern, Switzerland. To assess the incidence of malpositioning, a qualitative analysis of postoperative computed tomography scans, as well as comparative volumetric measurements of the orbits, was conducted. Furthermore, the incidence of and reason for secondary revision procedures were evaluated. RESULTS: From September 2008 to December 2015, a total of 71 emergency patients (73 implants) were treated at the Department of Cranio-Maxillofacial Surgery with a titanium mesh (48 male patients; mean age, 56 years). The implant position was rated as poor in 17 cases (23%) by the qualitative analysis. The volumetric assessment showed no significant results. Revision intervention was needed in 12 patients (17%) because of an unsuccessful treatment outcome causing relevant clinical symptoms. CONCLUSIONS: Patients with large orbital defects who require surgical treatment with a titanium mesh are at risk of implant malposition. Because in this study, poor positioning of the implant is the main reason for surgical revision, we postulate that a postoperative radiographic control should be obtained routinely. Only then can long-term sequelae due to inadequate reconstruction be avoided.

Effect of recombinant human bone morphogenic protein 9 (rhBMP9) loaded onto bone grafts versus barrier membranes on new bone formation in a rabbit calvarial defect model.

Recent research has demonstrated that recombinant human bone morphogenetic protein 9 (rhBMP9) has been considered the most osteoinductive growth factor of the BMP-family. In the present study, rhBMP9 was investigated for its influence in combination with two biomaterials for bone regenerative medicine. Either porcine-derived collagen membrane (CM) or deproteinized bovine bone mineral (DBM) combined with 20 µg of rhBMP9 were implanted in 6 mm rabbit calvarial defects. Bone augmentation was evaluated by microCT and histomorphometry at 8 weeks post-surgery. Both CM + rhBMP9 and DBM + rhBMP9 groups significantly promoted mineralized tissue volume (microCT) and area, new bone height and area (histomorphometric measurements) when compared to CM and DBM alone groups or control (empty). All specimens in the CM + rhBMP9 group but not all in the DBM + rhBMP9 group induced a complete horizontal bone defect closure. Multinucleated giant cells (MNGCs) were observed directly in contact with DBM surfaces irrespective of rhBMP9, whereas CM was generally not associated to the presence of MNGCs. When combined with rhBMP9, DBM augmented a larger volume of mineralized tissue (including the mineralized bone graft), whereas CM induced greater volume of native host bone. While DBM in combination with rhBMP9 induced higher mineralized tissue mostly associated with the bone grafting material, CM may have presented preferable results based on a higher horizontal defect closure with a faster regeneration of host new bone. The effect of including collagen within the carrier system of rhBMP9 on bone regeneration justifies further evaluation of this combination procedure in larger animal models. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2655-2661, 2017.

Stereographic measurement of orbital volume, a digital reproducible evaluation method.

BACKGROUND/AIMS: Up to date, no standardised reproducible orbital volume measurement method is available. Therefore, this study aimed to investigate the accuracy of a new measurement method, which delineates the boundaries of orbital cavity three-dimensionally (3D). METHODS: In order to calculate the orbital volume from axial CT slice images of the patients, using our first described measurement method, the segmentation of the orbital cavity and the bony skull was performed using Amira 3D Analysis Software. The files were then imported into the Blender program. The stereographic skull model was aligned based on the Frankfurt horizontal plane and superposed according to defined anatomical reference points. The anterior sectional plane ran through the most posterior section of the lacrimal fossa and the farthest dorsal point of the anterior latero-orbital margin, which is positioned perpendicular to the Frankfurt horizontal plane. The volume of each orbital cavity was then determined automatically by the Blender program. RESULTS: The 10 consecutive subjects (5 female, 5 male) with mean age of 50.3±21.3 years were considered for analysis in the current study. The first investigator reported a mean orbital volume of 20.24±1.01 cm3 in the first and 20.25±1.03 cm3 in the second evaluation. Furthermore, the intraclass correlation coefficient (ICC) showed an excellent intrarater agreement (ICC=0.997). Additionally, the second investigator detected a mean orbital volume of 20.20±1.08 cm3 in his assessment, in which an excellent inter-rater agreement was found in ICC (ICC=0.994). CONCLUSIONS: This method provides a standardised and reproducible 3D approach to the measurement of the orbital volume.

Periosteal distraction osteogenesis versus immediate periosteal elevation in a rat model: Histological and micro-CT analysis.

PURPOSE: The aim of the present study was to compare periosteal distraction osteogenesis (PDO) to immediate periosteal elevation (IPE) in terms of de novo bone formation. MATERIAL AND METHODS: Animals of PDO Group were subjected to a 7-day latency period and a 10-day distraction period. Distraction device in IPE Group were activated for 1 mm at placement. Both groups of animals were euthanized at 17, 31 and 45-day following surgery and the samples analyzed histologically and by micro-CT. Total gap region (TG) was divided in two subregions, less than 0.5 mm (LG) and over 0.5 mm of the gap height (HG). RESULTS: Bone formation in PDO Group was observed in the distal region of the distraction gap, whereas in IPE Group proximally and distally from the distraction gap. Bone volume increased in both groups in LG, HG and TG (p < 0.001), while bone mineral density only in HG (p = 0.001). More new bone was observed in PDO than in IPE Group in HG (p = 0.017) and in TG (p < 0.001), without differences found in bone mineral density. CONCLUSIONS: The function of immediately elevated periosteum is limited to the distance to the underlying bone. PDO may be successfully applied to maintain the osteogenic capacity of elevated periosteum.

An in vitro study of fibrin sealant as a carrier system for recombinant human bone morphogenetic protein (rhBMP)-9 for bone tissue engineering.

In the craniofacial bone field, fibrin sealants are used as coagulant and adhesive tools to stabilize grafts during surgery. Despite this, their exact role in osteogenesis is poorly characterized. In the present study, we aimed to characterize the osteogenic potential of TISSEEL fibrin sealant and used its technology to incorporate growth factors within its matrix. We focused on recombinant human bone morphogenetic protein (rhBMP)-9, which has previously been characterized as one of the strongest osteogenetic inducers in the BMP family. TISSEEL displayed an excellent ability to retain rhBMP9, which was gradually released over a 10-day period. Although TISSEEL decreased bone stromal ST2 cell attachment at 8 h, it displayed normal cell proliferation at 1, 3, and 5 days when compared to tissue culture plastic. Interestingly, TISSEEL had little influence on osteoblast differentiation; however its combination with rhBMP9 significantly increased ALP activity at 7 days, Alizarin Red staining at 14 days, and mRNA levels of osteoblast differentiation markers ALP, bone sialoprotein, and osteocalcin. In summary, although fibrin sealants were shown to have little influence on osteogenesis, their combination with bone-inducing growth factors such as rhBMP9 may serve as an attractive carrier/scaffold for future bone regenerative strategies. Future animal studies are now necessary.

Effects of collagen membrane application and cortical bone perforation on de novo bone formation in periosteal distraction: an experimental study in a rabbit calvaria.

OBJECTIVES: The aim of the present study was to assess the impact of collagen membrane application and cortical bone perforations in periosteal distraction osteogenesis. STUDY DESIGN: A total of 32 New Zealand rabbits were randomized into four experimental groups, considering two treatment modalities. Calvarial bone was perforated or left intact (P+/-). In half the animals, the distraction mesh was covered with a collagen membrane (M+/-). All animals were subjected to a 7-day latency period and a 10-day distraction period. The samples were harvested after 4-week and 8-week consolidation periods and analyzed histologically and by means of micro-computed tomography. RESULTS: Primary, woven bone observed at the 4-week consolidation period was gradually replaced by lamellar bone at the 8-week consolidation period. Significant increase in bone volume was found in all groups (P < .001) and in bone mineral density in groups I (P-/M-; P < .001), III (P+/M-; P < .001), and IV (P+/M+; P = .013). Group III (P+/M-) showed significantly more new bone at the 8-week consolidation period compared with the other three groups (P = .001), with no differences observed in bone mineral density between groups at a given time-point. CONCLUSIONS: In the present model, cortical bone perforations have more impact on the osteogenic process compared with the application of a collagen membrane.

New approach for virtual surgical planning and mandibular reconstruction using a fibula free flap.

Maxillofacial reconstruction poses a major challenge to surgeons because of the associated anatomical complexity, the sensitivity of the involved systems and the need to maintain a pleasing facial appearance. Here, we present a detailed description of a new method for extensive mandibular reconstruction using open-source virtual design software and a desktop 3D printer. A surgeon segmented preoperative computed tomography angiography scans with the Amira program to create a digital model of the mandible, skull and fibula. These datasets were imported into Blender, an open-source computer-aided design software package, where arrangement of the fibula segments into aligned sections was performed. Then, a desktop 3D printer was used to produce a reconstructed mandible. After fixation of a plate onto the reconstructed mandible, cutting guides were digitally designed using Blender. Following this, the surgeon performed mandible resection using the fixed cutting guides, which were 3D-printed using biocompatible plastic (Med 610/Stratasys Inc.) and fixed to the prebent reconstructed mandible at a predetermined position. After cutting the fibula with the help of the cutting guides and aligning the fibular segments into mandibular space, the surgeon fixed the segments to the reconstruction plate. Postoperatively, multislice computed tomography scans were taken for control purposes. Our method for mandibular reconstruction offers the following benefits: shorter operation planning time, increased accuracy during osteotomy through the use of a special fibula cutting guide and low costs. In brief, this method is an easy, precise and highly flexible technique for mandibular reconstruction with a fibula flap.

Single-staged vs. two-staged implant placement using bone ring technique in vertically deficient alveolar ridges - Part 1: histomorphometric and micro-CT analysis.

BACKGROUND: Simultaneous implant placement with bone grafting shortens the overall treatment period, but might lead to the peri-implant bone loss or even implant failure. The aim of this study was to compare the single-staged to two-staged implant placement using the bone ring technique. MATERIAL AND METHODS: Four standardized alveolar bone defects were made in the mandibles of nine dogs. Dental implants (Straumann BL® , Basel, Switzerland) were inserted simultaneously with bone ring technique in test group and after 6 months of healing period in control group. Animals of both groups were euthanized at 3 and 6 months of osseointegration period. The harvested samples were analyzed by means of histology and micro-CT. RESULTS: The amount of residual bone decreased while the amount of new bone increased up to 9 months of healing period. All morphometric parameters remained stable between 3 and 6 months of osseointegration period within groups. Per a given time point, median area of residual bone graft was higher in test group and area of new bone in control group. The volume of bone ring was greater in test than in control group, reaching the significance at 6 months of osseointegration period (P = 0.002). CONCLUSIONS: In the present type of bone defect, single-staged implant placement may be potentially useful to shorten an overall treatment period.

The role of postoperative prophylactic antibiotics in the treatment of facial fractures: a randomised, double-blind, placebo-controlled pilot clinical study. Part 3: Le Fort and zygomatic fractures in 94 patients.

The aim of this study was to evaluate the difference between the effect of a 5-day and a 1-day postoperative course of antibiotics on the incidence of infection after midfacial fractures. A total of 98 patients with displaced Le Fort or zygomatic fractures that required operation were randomly assigned into 2 groups, both of which were given amoxicillin/clavulanic acid 1.2g intravenously every 8h from the time of admission until 24h postoperatively. The 5-day group was then given amoxicillin/clavulanic acid 625 mg orally 8-hourly for another 4 days. The 1-day group was given placebo orally at the same time points. Patients were followed up 1, 2, 4, 6, and 12 weeks, and 6 months, postoperatively. The development of an infection of the wound was the primary end point. Ninety-four of the 98 patients completed the study. Two of the 45 patients in the 5-day group (4%) and 2/49 in the 1-day group (4%) developed postoperative wound infections. One in each group had a purulent infection, while the others had only wound breakdown. Two patients of the 5-day group and one in the 1-day group developed rashes on the trunk. There were no significant differences in the incidence of infection or side effects between the groups. In midfacial fractures a 1-day course of antibiotics postoperatively is as effective in preventing infective complications as a 5-day regimen.

The role of postoperative antibiotics in facial fractures: comparing the efficacy of a 1-day versus a prolonged regimen.

BACKGROUND: The goal of this study was to evaluate the influence of the duration of postoperative antibiotics (1 day vs. ≥ 5 days) on wound infections following surgical treatment of facial fractures. METHODS: Three hundred thirty-nine patient case histories with a total of 498 fractures were reviewed retrospectively with regard to infections occurring within a 6-month period following surgical management. Patients were divided into two groups based on the duration of postoperative antibiotics administered. Group A consisted of 125 patients who had 1 day of postoperative antibiotics, whereas Group B consisted of 214 patients who had five or more days of postoperative antibiotics. Statistical analysis was conducted to assess for possible differences in the rate of postoperative infections. RESULTS: Five patients in Group A (4%) and seven patients in Group B (3.27%) developed infections within the follow-up period. Of these 12 patients, seven had sustained multiple facial bone fractures. Eleven infections occurred in patients with mandibular fractures and one in a midfacial fracture. Statistical analysis using Fisher's exact test showed no significant difference (p = 0.77) in the incidence of infection between Groups A and B. CONCLUSION: In this retrospective study, the use of prolonged postoperative antibiotics in uncomplicated mandibular and midfacial fractures had no significant benefit in reducing the incidence of infections. LEVEL OF EVIDENCE: Therapeutic study, level IV.

Long-term outcome in patients with mild traumatic brain injury: a prospective observational study.

BACKGROUND: Mild traumatic brain injury (MTBI) is common; up to 37% of adult men have a history of MTBI. Complaints after MTBI are persistent headaches, memory impairment, depressive mood disorders, and disability. The reported short- and long-term outcomes of patients with MTBI have been inconsistent. We have now investigated long-term clinical and neurocognitive outcomes in patients with MTBI (at admission, and after 1 and 10 years). METHODS: Patients of a previous study investigating MTBI short-term outcome were prospectively reassessed after ±10 year using the same standardized data entry form and validated questionnaire (Beltztest with Beltz Score [BeSc]) for evaluation of Quality of life (QoL) and neurocognitive outcome (higher scores indicate lower QoL). RESULTS: Eighty-six of 176 patients (49%) could be reassessed (n = 75 lost to follow-up; n = 8 second brain trauma; n = 7 death), 10.4 ± 2 years after initial evaluation. Over time, overall BeSc was significantly increased (5.92 ± 10.3 [admission] vs. 10.7 ± 12.8 [1 year] vs. 20.86 ± 17.1 [10 year]; p < 0.0001); only 54 of 86 patients (62.8%) presented with a normal BeSc. Long-term complaints were fatigue, insomnia, and exhaustion. Ten of eighty-six patients (11.6%) had intracranial injury (ICI) and initial BeSc was almost twofold higher in patients with ICI than in patients without ICI (10.0 ± 8.4 vs. 5.3 ± 9.6; p = 0.007). This difference was not seen after 1 year or after 10 years (10.3 ± 11.6 vs. 10.3 ± 10.1 and 21.4 ± 17.3 vs. 16.1 ± 16.4, respectively). Eight of eighty-six patients (9.3%) lost their jobs because of persistent complaints after MTBI. CONCLUSION: BeSc deteriorates over time; our data suggest a decline in general health and QoL in a substantial proportion of patients (37.2%) 10 years after MTBI. Patients without ICI appear to have a better long-term outcome with regard to subjective complaints and QoL.