[Show abstract][Hide abstract] ABSTRACT: Orthognathic surgery requires stable fixation for uneventful healing of osteotomized bony segments and optimal remodeling. Titanium plates and screws have been accepted as the gold standard for rigid fixation in orthognathic surgery. Although titanium osteofixation is the most widely used approach, the use of bioabsorbable devices has been increasing recently. Biodegradation of bioabsorbable devices eliminates the need for a second operation to remove metal plates and screws. However, long-term stability and relapse frequency in bioabsorbable osteofixation are still insufficiently studied, especially in cases of segmental movements of great magnitude or segmental movements to a position where bony resistance exists. This paper reviews the background, techniques, and complications of bioabsorbable osteofixation and compares bioabsorbable and titanium osteofixation in orthognathic surgery in terms of skeletal stability.
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to investigate the effect of a botulinum toxin type A (BTX-A) injection in the masseter muscle using electromyography (EMG) in an animal model.
Ten male adult (>3 months of age) New Zealand white rabbits were used. Muscle activity was continuously recorded from 8 hours before to 8 hours after BTX-A injection. The rabbits received unilateral BTX-A injections of either 5 units (group 1, n = 5) or 20 units (group 2, n = 5).
The masseter muscle activity of the rabbits was significantly reduced immediately after BTX-A injection (P < 0.05 for both groups). When the results from group 1 were compared with those from group 2, only the peak voltage was significantly decreased in group 2 (P = 0.013).
Masseter muscle activity measured by EMG was immediately decreased after a BTX-A injection.
[Show abstract][Hide abstract] ABSTRACT: Osteochondroma is rarely reported in the maxillofacial region; however, it is prevalent in the mandibular condyle. This slowly growing tumor may lead to malocclusion and facial asymmetry. A 39-year-old woman complained of gradual development of anterior and posterior unilateral crossbite, which resulted in facial asymmetry. A radiological study disclosed a large tumor mass on the top of the left mandibular condyle. This bony tumor was surgically removed through condylectomy and the remaining condyle head was secured. Subsequently, bimaxillary orthognathic surgery was performed to correct facial asymmetry and malocclusion. Pathological diagnosis was osteochondroma; immunohistochemistry showed that the tumor exhibited a conspicuous expression of BMP-4 and BMP-2 but rarely expression of PCNA. There was no recurrence at least for 1 year after the operation. Patient's functional and esthetic rehabilitation was uneventful.
[Show abstract][Hide abstract] ABSTRACT: Purpose: This study evaluated woven silk textile for burn wound dressing materials in an animal model. Methods: Ten rats were used in this experiment. Full-thickness 2×2 cm burn wounds were created on the back of the rats under anesthesia. In the experimental group, the wounds were treated with three different dressing materials from woven silk textile. In the control group, natural healing without any dressing material was set as control. The wound surface area was measured at five days, seven days, and 14 days. Wound healing was evaluated by histologic analysis. Results: There were no statistically significant differences among groups at five days post injury. The mean defect size at seven days was largest in Group 3 (462.87 mm 2), and smallest in Group 1 (410.89 mm 2), not a significant difference (P =0.341). The mean defect size at 14 days was smallest at the Group 3 (308.28 mm 2) and largest in the control group (388.18 mm 2), not a significant difference (P =0.190). The denuded area was smaller in Group 1 (84.57 mm 2) and Group 2 (82.50 mm 2) compared with the control group (195.93 mm 2), not statistically significant differences (P =0.066, 0.062). The difference between Group 3 and control was also not statistically significant (P =0.136). In histologic analysis, the experimental groups re-epithelialized more than control groups. No evidence was found of severe inflammation. Conclusion: The healing of burn wounds was faster with silk weave textile more than the control group. There was no atypical inflammation with silk dressing materials. In conclusion, silk dressing materials could be used to treat burn wounds.
[Show abstract][Hide abstract] ABSTRACT: The radial forearm free flap (RFFF) is a thin and pliable tissue with many advantages for tongue reconstruction. However, tongues reconstructed with RFFF occasionally need revision surgery because inadequate defect measurement at primary surgery can lead to bulkiness and limited movement of reconstructed tongue. In this case, the patient underwent partial glossectomy and RFFF reconstruction for treatment of tongue cancer five years prior. We could not make a lower denture for the patient, because the alveolo-lingual sulcus of tongue was almost lost. So we performed vestibuloplasty with a modified Kazanjian method on the lingual vestibule of the mandibular right posterior area, and defatting surgery to debulk the flap. After surgery, we observed that the color and texture of the revised tongue changed to become similar with adjacent tissue. The patient obtained a more functional and esthetic outcome. Accordingly, we present a case report with a review of relevant literature.
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to evaluate silkworm-cocoon-derived silk membrane (SM) for application in guided bone regeneration (GBR) and to compare it with commercially available GBR membranes, such as collagen membrane (CM) and polytetrafluoroethylene membrane (PM). The SM, CM, and PM membranes were examined via scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) analysis, and tensile strength evaluation. Thirty rats were used for the experiments. Critical-sized parietal bone defects (diameter: 8.0 mm) were divided into three groups according to the applied GBR membrane. The rats were sacrificed 4 or 8 weeks after surgery and evaluated by micro-compiterized tomography (µ-CT) and histology. The FTIR analysis of the SM was similar to that of the CM. The SEM images showed that the surface characteristics of the SM differed from those of the CM and PM. The SM showed a complex network structure of silk fibers. The wet SM was also more resistant to tensile stress than the wet CM and PM. The µ-CT results of the animal study showed that the bone volume of the SM group was higher than those of the CM and PM groups 4 weeks after the operation (p<0.05). The histological analysis showed that the new bone regeneration of the SM group was higher than those of the CM and PM groups 4 and 8 weeks after the operation (p<0.05). This study demonstrated that the tensile strength of the wet SM was higher than the tensile strength of the wet CM and PM groups. The bone formation of the SM group was higher than those of the other two groups.
Macromolecular Research 09/2014; 22(9):1018-1023. DOI:10.1007/s13233-014-2138-2 · 1.60 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: There are many treatment options in management of mandibular condylar neck fractures. Closed reduction is the most conservative treatment; however, achievement of anatomic reduction is difficult, and there are some risks of mandibular functional impairment. Open anatomic reduction and internal fixation have some advantages; therefore, many oral and maxillofacial surgeons have attempted to achieve anatomic reduction through the open approach and extracorporeal reduction and fixation. However, when using this method, there is some risk of resorption of the fractured mandibular condylar head. Therefore, we designed a modified extracorporeal reduction technique, without detaching the lateral pterygoid muscle in order to maintain the blood supply to the fractured mandibular condylar head. We believe that this minor modification may minimize the risk of resorption of the fractured mandibular condylar head. In this article, we introduce this technique in detail, and report on two cases.
[Show abstract][Hide abstract] ABSTRACT: A 60-year-old male complained of headache, nasal discharge, and diplopia for over one month with a history of left upper molar extraction, and he had recently experienced severe discharge of purulent exudate from his left antrum. Under the diagnosis of maxillary sinusitis, the Caldwell-Luc operation was performed, and several fragments of amorphous white mucoroid materials were removed. In the histological observation, sinus mucosa was relatively well preserved, but showed diffuse infiltration with eosinophilic polymorphonuclears. Huge molds of mucormycosis were associated with the surface of mucosa. He was treated with amphotericin-B deoxycholate, resulting in the uneventful healing of the antral lesion. The current case of antral mucormycosis was very rare but effectively treated by surgical removal of antral mucosa and the following antibiotic therapy for the strong inhabitants of fungal molds. We also presumed that the patient was superinfected with commensal fungus of mucormycosis during broad spectrum antibiotic therapy for the previous dental infection.
[Show abstract][Hide abstract] ABSTRACT: Purpose: For reconstruction of craniomaxillofacial defects caused by tumor, trauma, infection etc, free flap transplantation with microvascular surgery is a very useful method. Thrombus formation at the anastomosis site is the major cause of graft failure. 4-Hexylresorcinol (4-HR) is generally known as an antiseptic and antiparasitic agent. This study was conducted in order to evaluate the effect of 4-HR on blood coagulation in vitro. In addition, we investigated thrombus formation and endothelial repair of an injured vessel in an animal model. Methods: In the in vitro experiment, we compared blood coagulation time between the 4-HR treated group and normal blood. Thirty rats were used for in vivo animal experiments. After exposure of the right femoral vein, a micro vessel clamp was placed and the femoral vein was intentionally cut. Microvascular anastomosis was performed on all rats using 10-0 nylon under microscopy. The animals were divided into two groups. In the experimental group (n=15), 4-HR (250 mg/kg) mixed with olive oil (10 mL/kg) was administered per os daily. Animals in the control group (n=15) were given olive oil only. The animals were sacrificed at three days, seven days, and fourteen days after surgery and rat femoral vein samples were taken. Vascular patency and thrombus formation were investigated just before sacrifice. Histologic analysis was performed under a microscope. Results: Results of an in vitro blood coagulation test showed that coagulation time was delayed in the 4-HR treated group. The results obtained from an in vivo 4-HR administered rat model showed that the patency of all experimental groups was better at thirty minutes, seven days, and fourteen days after microvascular anastomosis than that of the control group at seven and fourteen days after anastomosis, and the amount of thrombus in the experimental groups was much less than that of the control group. Endothelial repair was observed in the histologic analysis. Conclusion: Findings of this study demonstrated that blood coagulation was delayed in the vitro 4-HR treated group. In addition, good vascular patency, anti-thrombotic effect, and repair of venous endothelial cells were observed in the vivo 4-HR administered rat group.
[Show abstract][Hide abstract] ABSTRACT: Post-traumatic anterior open bite can occur as a result of broken balance among the masticatory muscles. The superior hyoid muscle group retracts the mandible downward and contributes to the anterior open bite. Denervation of the digastric muscle by injection of botulinum toxin type A (BTX-A) can reduce the power of the digastric muscle and help to resolve the post-traumatic anterior open bite. A patient with a bilateral angle fracture had an anterior open bite even after undergoing three operations under general anesthesia and rubber traction. Although the open bite showed some improvement by the repeated operation, the occlusion was still unstable six weeks after the initial treatment. To eliminate the residual anterior open bite, BTX-A was injected into the anterior belly of the digastric muscle. Following injection of BTX-A, the anterior open bite showed immediate improvement. Complication and relapse were not observed during follow-up. Long-standing post-traumatic open bite could be successfully corrected by injection of BTX-A into the anterior belly of the digastric muscle without complication.
[Show abstract][Hide abstract] ABSTRACT: Oblique facial cleft is a rare congenital deformity. Its incidence has been reported as 0.24% of all reported cases of facial cleft. We report on a patient who had a left-sided oblique facial cleft with anopthamia, including lip and palate, nose alar base, and medial canthus. The patient also had a right-sided oblique facial cleft, which included lip and palate, nose alar base, medial canthus, and upper eye brow. Primary closure of the facial cleft was performed using multiple Z-plasty after excision of scar tissue.
[Show abstract][Hide abstract] ABSTRACT: Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a disease characterized by jaw necrosis and delayed wound healing in patients who had received bisphosphonates. Buccal fat pad (BFP) can be used as a pedicled flap in the posterior region of the oral cavity. BFP pedicle flap needs simple surgical technique and it shows less donor site morbidity and aesthetic problem than other vascularized flap. BFP pedicled flap was fed by 3 arteries-facial, internal maxillary, and transverse facial artery. Osteomyelitis was generally related with poor blood supply. Thus, rich blood supply of BFP pedicle flap can have a potential advantage to BRONJ patients. In this case report, we presented 3 BRONJ patients treated by BFP pedicle flap after sequestrectomy.
[Show abstract][Hide abstract] ABSTRACT: The present study was undertaken to examine the effects of cisplatin plus 4-hexylresorcinol (4-HR) combination therapy on oral mucosal melanoma (OMM) using cultured primary OMM cells in a tumour xenograft model. Cultured primary OMM cells were used for the MTT assay and DNA microarray. OMM cells were implanted into the submandibular glands of nude mice. The mice were then treated with cisplatin only or cisplatin plus 4-HR. Tumour size changes, survival rate and tumour metastasis were compared between the two groups by observation, micro-positron emission tomography (PET) and histological examination. In the MTT assay, the cisplatin plus 4-HR group showed significantly higher inhibition of OMM cell growth compared to the other groups (p < 0.05). DNA microarray results showed significant inhibition of matrix metalloproteinase (MMP)-2 gene expression upon 4-HR application. The necropsy and micro-PET results showed that the mice from the cisplatin-only group had more distant metastases than the mice from the cisplatin plus 4-HR combination group (p = 0.002). MMP-2 expression was lower in the primary tumours in the cisplatin plus 4-HR combination group than in the cisplatin-only group (p < 0.001). Overall survival was longer in mice from the cisplatin plus 4-HR combination group than in the cisplatin-only group (p = 0.049). In conclusion, the combined effect of cisplatin and 4-HR resulted in fewer metastases and longer survival than cisplatin-only treatment in the OMM xenograft model.
[Show abstract][Hide abstract] ABSTRACT: Bisphosphonates (BP) are widely used in medicine for inhibiting bone resorption; however bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a major side effect of BP. To date, there have been no specific reports on the incidence of BRONJ among Koreans. This study investigated the preliminary results from a nationwide survey of BRONJ in the Departments of Oral and Maxillofacial Surgery (OMFS) at individual training hospitals.
A total of 15 OMFS departments (10 from dental schools, 4 from medical schools, and 1 from a dental hospital) participated in a multi-centric survey. This study assessed every BRONJ case diagnosed between January 2010 and December 2010. The patient age and BP type were evaluated.
A total of 254 BRONJ cases were collected. The majority of BRONJ cases were associated with oral BP therapy, while 21.8% of the cases were associated with intravenous administration. Alendronate was the drug most frequently related to BRONJ (59.2% of cases), followed by risedronate (14.3%) and zolendronate (17.0%). The average age of BRONJ patients was 70.0±10.1 years, with a range of 38-88 years of age. With the number of BP patients in Korea reported to be around 600,000 in 2008, the estimated incidence of BRONJ is at least 0.04% or 1 per 2,300 BP patients.
The results suggest that the estimated incidence of BRONJ in Korea is higher than the incidence of other countries. Future prospective studies should be carried out to investigate the exact epidemiological characteristics of BRONJ in Korea.
[Show abstract][Hide abstract] ABSTRACT: Purpose: Vascular endothelial growth factor (VEGF)-C and its tyrosine kinase receptor, VEGF receptor (VEGFR)-3 are recently known to have lymphangiogenic activities in various tumor types. In this study, we determined whether the expression of lymphangiogenic factors correlate with nodal metastasis or survival in a nude mouse model of oral squamous cell carcinoma (OSCC). Methods: Three OSCC cells (KB, SCC4, SCC9) were xenografted into the right mandibular gland of athymic nude mice. The mice were followed for tumor development and growth, and the mice were sacrificed when they had lost more than 20% of their initial body weight, or the diameter of the induced tumor exceeds 20 mm. After necropsy, the murine tumors were examined histologically and radiologically (micro-positron emission tomography computed tomography) for regional or distant metastasis. We performed immunohistochemical assays with anti-VEGF-C, VEGFR-3, CD105, and D2-40 antibodies. Immunofluorescence double staining for LYVE-1/CD31 was also performed. To quantify the VEGF-C and VEGFR-3 level in the cancer tissue, Western blotting was performed. Finally, we determined the correlation between the degree of expression of VEGF-C/VEGFR-3 and the mean survival time. Results: OSCC tumor cells into the mandibular gland of the nude mice successfully resulted in the formation of recapitulating orthotopic tumor. Tumor cells of the induced tumor did not express VEGF-C. VEGF-C/VEGFR-3 expression was mainly distributed in the endothelial cells of the stromal area. There were no correlation between the degree of expression of VEGF-C/VEGFR-3 and the mean survival time of mice injected with different OSCC cell lines. Conclusion: An recapitulating orthotopic model of OSCC in nude mice was established, which copies the cervical nodal metastasis of human OSCC. Overexpression of lymphangiogenic factors seems to have no effect on survival of hosts in this in vivo experiment.
[Show abstract][Hide abstract] ABSTRACT: Maxillary sinus hypoplasia (MSH) is an uncommon clinical disease that represents a persistent decrease in sinus volume, which results from centripetal reaction of the maxillary sinus walls. We present a unilateral MSH case of a 46-year-old male patient with a history of nasal obstruction and headache for 3 years. He had a history of Caldwell Luc operation (CLOP) 10 years ago, and no enophthalmos, hypoglobus or facial asymmetry. After confirming the right diagnosis of MSH, filled with bone in the computed tomography scan, hyperplastic bone was removed by the CLOP approach. The uncinate process and infundibular passage were found to be degenerated and ostium was also examined to be obstructed under endoscopic confirmation. MSH can be mistaken for chronic maxillary sinusitis because of the plain x-ray appearance, so the aggravated state of MSH can be the result of surgeon's misjudgment. With additional literature reviews, this rare experience is first introduced in our Korean oral and maxillofacial surgery field.
[Show abstract][Hide abstract] ABSTRACT: Angiogenesis and lymphangiogenesis are correlated with tumor growth and lymph node metastasis in cases of oral squamous cell carcinoma (OSCC). Endoglin is one of the representative vascular endothelial cell markers. Podoplanin is also a representative marker used in order to detect lymphatic endothelial cells. The aim of this study was to determine the correlation between the expression of endoglin/podoplanin and clinical variables associated with OSCC progression.