Investigation of orthognathic surgery indicators-combination with index of orthognathic functional treatment needs (IOFTN) and maxillofacial morphometric analysis.

PURPOSE: The aim of this retrospective study was to determine orthognathic surgery indicators for Japanese patients with jaw deformities using both Index of Orthognathic Functional Treatment Needs (IOFTN) and maxillofacial morphometric analysis. SUBJECTS AND METHODS: The subjects were 89 patients treated with orthognathic surgery and 92 patients treated with orthodontic treatment alone, and were classified as class I, II, or III according to the ANB angle. Based on the results for IOFTN and the results of cephalometric analysis, the indication criteria for orthognathic surgery were examined. RESULTS: In IOFTN analysis, none of patients in the orthognathic surgery group were classified as category 1 or 2, while 48% of the patients in the orthodontic treatment group were classified as category 4 or 5. The results of the cephalometric analysis of patients in classified categories 4 and 5 showed that the orthognathic surgery group had significantly greater lateral mandibular deviation in Class I cases, significantly more severe degree of mandibular retrusion in Class II cases, and significantly more severe degree of mandibular prognathism in Class III cases. The results of the logistic regression analysis showed that IOFTN was a common variable as an indication criterion for orthognathic surgery, and several different variables were also selected from the cephalometric measurements in each group. CONCLUSION: IOFTN is a highly sensitive and useful indicator as a criterion for orthognathic surgery. However, in the choice of treatment strategy, maxillofacial morphometric analyses and the patient's desired goal are important.

Changes in nutritional status of patients with jaw deformities due to orthognathic surgery.

OBJECTIVE: In orthognathic surgery, it is important to carefully manage peri-operative nutrition because maxillomandibular fixation and problems such as swelling and pain after surgery may make it difficult to eat normally and may prevent adequate nutrition. This study investigated the changes in nutritional status of patients with jaw deformities due to orthognathic surgery. STUDY DESIGN: The subjects were 155 jaw deformity patients, who underwent orthognathic surgery. The nutritional status was evaluated using anthropometry immediately before and 10 days after surgery and clinical laboratory results and the controlling nutritional status (CONUT) score before surgery and immediately, 1 week and >6 months after surgery. We investigated the relationship among the nutritional status, surgical procedures, and dietary intake in patients who underwent orthognathic surgery. RESULTS: The surgical procedure time and amount of bleeding were significantly greater as the surgical procedure became more complex. All of the laboratory values and CONUT scores were significantly decreased immediately after surgery and then increased over time, recovering to the same level as before surgery except for serum albumin at >6 months after surgery. CONCLUSIONS: Nutritional management is considered as one of the key factors for the better and faster recovery after the orthognathic surgery.

Migration and phenotype switching of macrophages at early-phase of bone-formation by secretomes from bone marrow derived mesenchymal stem cells using rat calvaria bone defect model.

BACKGROUND/PURPOSE: Conditioned media of cultured mesenchymal stem cells (MSCs) contain numerous kinds of secretomes such as cytokines and chemokines. We previously reported that conditioned media of bone marrow-derived MSCs (MSC-CM) promote bone formation. Recently, macrophage phenotype switching from the pro-inflammatory M1 type to the anti-inflammatory M2 type has been reported to be an important phenomenon during tissue regeneration. Some studies reported that this phenotype switching is regulated by secretomes. In this study, macrophage phenotype during bone formation by MSC-CM was investigated. MATERIALS AND METHODS: Human MSCs (hMSCs) were cultured in serum-free medium and the collected medium was defined as MSC-CM. Macrophage-related gene expressions in hMSCs cultured with MSC-CM were evaluated by quantitative real-time polymerase chain reaction. MSC-CM was implanted and the evaluations by micro-CT and immunohistochemistry were performed using a rat the calvaria bone defect model. RESULTS: Two and four weeks after implantation, the MSC-CM group demonstrated enhanced bone regeneration. Gene expressions of C-C motif chemokine 2 (CCL2), colony-stimulating factor 2 (CSF2) and CD163 was significantly upregulated in cells exposed to MSC-CM. Immunohistochemical staining revealed that iNOS-positive M1 macrophages were reduced, while CD204-positive M2 macrophages were increased in the MSC-CM group at 72 h after implantation, and the M2/M1 ratio increased only in the MSC-CM group. CONCLUSION: MSC-CM enhances macrophage migration and induces M1 to M2 type macrophage switching at an early stage of osteogenesis. Such phenotype switching provides a favorable environment for angiogenesis, cellular migration, and osteogenesis and contributes to MSC-CM-induced early bone formation.

The use of an ultrasonic curettage device in orthognathic surgery decreases surgery-related blood loss.

Objective: This study aimed to compare the use of a powered instrument (PI) and ultrasonic curettage device (ULCD) with intraoperative blood loss (IOBL), drain volume (DV), calculated blood loss (CBL), and hidden blood loss (HBL) in orthognathic surgery. Methods: We included 163 patients who underwent bimaxillary surgery in our department. CBL was calculated from the preoperative and postoperative hemoglobin levels using the "hemoglobin balance method." CBL is an indicator of the amount of perioperative blood loss. HBL was calculated by subtracting IOBL and DV from CBL. Results: The PI group consisted of 61 patients (17 males and 44 females, age: 24.9 ± 9.5 years), and the ULCD group consisted of 102 patients (40 males and 62 females, age: 23.1 ± 7.8 years). In the PI group, the median IOBL, DV, CBL, and HBL were 540.0 (interquartile range [IQR] 380.0-670.0), 113.0 (IQR 77.0-147.0), 1000.0 (IQR 751.4-1248.6), and 285.8 (IQR 151.0-476.4) ml, respectively. In the ULCD group, the median IOBL, DV, CBL, and HBL were 327.5 (IQR 200.0-455.0), 105.5 (IQR 75.3-136.0), 759.5 (IQR 594.9-944.2), and 294.2 (IQR 120.8-456.9) ml, respectively. IOBL and CBL were significantly reduced with ULCD use, but no significant differences were observed in DV and HBL. Conclusions: This study showed that IOBL decreased with ULCD use, resulting in a decrease in CBL. Conversely, bleeding parameters (DV and HBL), which reflect the amount of bleeding that occurs after wound closure, did not show a decrease with ULCD use.

Conditioned medium from mesenchymal stem cells improves condylar resorption induced by mandibular distraction osteogenesis in a rat model.

Condylar resorption (CR) after surgical orthognathic treatment is defined as dysfunctional remodeling of the temporomandibular joint manifested by morphological changes with decreased condylar head volume that cause occlusal and esthetic changes. Although both conservative and surgical treatment strategies have been employed for the treatment of CR, effective procedures have not been established till date. In this study, the effects of MSC-CM on CR were investigated. Bone marrow-derived MSCs of rats (rMSCs) were cultured until 80% confluent, cultured in serum-free conditioned medium for 48 h; the collected medium was defined as MSC-CM. Osteogenesis, chondrogenesis, and angiogenesis-related gene expression in rMSCs cultured with MSC-CM was evaluated by quantitative real-time polymerase chain reaction. A rat CR model was used for animal studies, in which CR occurred after mandibular distraction osteogenesis for 10 days. MSC-CM was injected via the tail vein and quantitative and qualitative evaluations were performed by micro-computed tomography (micro-CT) and histology. MSC-CM enhanced osteogenesis-, chondrogenesis-, and angiogenesis-related gene expression in rMSCs. Micro-CT showed CR in control groups; however, it was observed to be improved in the MSC-CM group. Histologically, an enlarged cartilage layer was seen in the MSC-CM group, while cartilage layers had almost thinned or disappeared in control groups. These results indicate that MSC-CM improved CR.

Vertical distraction osteogenesis of a reconstructed mandible with a free vascularized fibula flap: a report of two cases.

BACKGROUND: The free vascularized fibula flap presents many advantages such as sufficient length of the bony segment, good vascularization, better quality of the bone, and a long vascular pedicle, but it is also associated with some disadvantages with regard to prosthetic rehabilitation because of its limited height. Improvement in bone height is necessary for ideal dental implant treatment of reconstructed mandibles. CASE PRESENTATION: For two squamous cell carcinoma patients, mandibular bone reconstruction was performed secondarily with the peroneal flap after tumor resection. Since the bone height was insufficient at the time of implant treatment, occlusion reconstruction by dental implant was performed after vertical distraction osteogenesis. CONCLUSIONS: Vertical distraction osteogenesis is a suitable treatment option for alveolar ridge deficiency resulting from fibula transplantation for mandibular reconstruction following tumor surgery.

The effect of bone mass and architecture on mandibular condyle after mandibular distraction.

OBJECTIVE: Mandibular distraction surgery is a critical treatment for jaw deformity. However, abnormal mandibular condylar bone resorption is often seen as complication after surgery. Our previous study using a rat mandibular distraction model suggested that overloading leads to mandibular condylar resorption. Host factors are also believed to influence the resorption. To understand the relationship between host factors and resorption, we investigated the effect of changing bone mass and architecture on the mandibular condyle using FK506. STUDY DESIGN: FK506, an immunosuppressant, was used to compromise bone mass and architecture in this study. Animals were divided into 4 groups: distraction surgery (Dist), FK506 administration (FK), distraction surgery with FK506 administration (FK + Dist), and no surgery or FK506 administration (Cont). RESULTS: The FK group showed reduced bone mass and impaired bone architecture. The Dist group exhibited abnormal bone resorption on the surface of the condyles, which was slightly exacerbated in the FK + Dist group. Bone defect length decreased over time as a result of bone apposition in the Dist group. However, in the FK + Dist group, the bone defect length remained the same. CONCLUSIONS: These results suggest that bone mass and architecture strongly affect the tolerance to the overloading and adaptation with bone apposition in condylar resorption site.