Risk Factors of Fixation Failure in Femoral Neck Fractures

Purpose@#Internal fixation after a femoral neck fracture (FNF) is one of the conventional treatment options for the young and active elderly patients. However, fixation failure of internal fixation is a probable complication. The treatment of fixation failure after a primary internal fixation of the FNF remains a challenge. @*Materials and Methods@#Between July 2002 and March 2017, 83 patients who underwent internal fixation after FNF were retrospectively analyzed. Radiological assessments, including Pauwels’ angle, fracture level, reduction quality, and bone union, were measured, preoperatively and postoperatively.Moreover, intraoperative variables such as time to surgery, surgical time, and estimated blood loss were also evaluated. @*Results@#The patients were divided into the fixation failure and the non-failure groups. Among the 83 patients, 17 cases (20.5%) of fixation failure after the primary internal fixation of the FNF were identi-fied. When comparing the two groups according to the radiographic data, Pauwels’ angle and the reduction quality based on Garden’s angle showed significant differences (p<0.001). Moreover, when comparing the intraoperative variables, unlike the surgical time and estimated blood loss, significant differences were noted in the time interval from injury to surgery and specifically in whether the surgery was performed within 12 hours after injury (p<0.001). @*Conclusion@#Pauwels’ angle, reduction quality, and time to surgery are the major factors that can predict the possibility of internal fixation failure of the FNF. Early and accurate anatomical reduction is needed to decrease complications after the internal fixation of the FNF.

Use of Three-Column Reconstruction and Free Vascularized Fibular Grafts for the Repair of Large Tibial Defects after Tumor Resection

Background@#This study aimed to evaluate the clinical outcomes of three-column reconstruction of the lower leg using a singlebarrel contralateral vascularized fibular graft (VFG), medial locking plate, and the ipsilateral fibula for the repair of large tibial defects after tumor resection. @*Methods@#In this retrospective study, we reviewed 12 patients who underwent three-column reconstruction using a single-barrel contralateral VFG, medial locking plate, and the ipsilateral fibula between June 1996 and May 2020. These patients had large tibial bone defects following tumor resection. The mean age of the patients was 26.3 years (range, 11–63 years), and 7 of them were women. The mean follow-up period was 104.8 months (range, 26–284 months). The mean size of the tibial bone defect after tumor resection was 17.8 cm (range, 11–26.8 cm). The clinical and radiological outcomes were evaluated at the final follow-up. @*Results@#All patients survived beyond the final follow-up without recurrence of the primary bone tumor. The mean time from reconstruction to bony union at both host-graft junctions was 12.9 months (range, 4–36 months). The mean Musculoskeletal Tumor Society score was 82.3% (range, 60%–97%). All tibial defects were reconstructed with adequate bone healing. There were 4 cases of stress fracture and graft failure; these were resolved by using longer plates and more screws. All patients were ambulatory without assistance and showed no permanent complications. @*Conclusions@#Large tibial defects that occur after tumoral resection can be effectively reconstructed by three-column reconstruction using a medial locking plate, an inlay single-barrel VFG harvested from the contralateral side, and the intact ipsilateral fibula.This technique permits early weight-bearing before fibular hypertrophy and bony union.

The impact of COVID-19 through epidemiological changes in out-of-hospital cardiac arrest patients: a study in a single emergency medical center

Objective@#This study compared the epidemiological changes before and after the coronavirus disease 2019 (COVID-19) outbreak in out-of-hospital cardiac arrest patients in a single center. This study analyzed the long-term impact of the COVID-19 pandemic. @*Methods@#Eight hundred and sixty-one out-of-hospital cardiac arrest patients were included in the analysis. Out-of-hospital cardiac arrest patients from January 20, 2018, to January 19, 2020, were used as the control group, and those between January 20, 2020, and January 19, 2022, were used as the study group. The collected data were evaluated using a Student t-test, chi-square test, and logistic regression analysis. @*Results@#During the COVID-19 pandemic, the number of cardiac arrests witnessed at the field level decreased. In the transport stage, mechanical CPR increased and the method for securing the airway had many changes. Transport distances, response times, and on-scene times have increased. Survival discharge from hospital decreased from 9.5% to 5.8% (P=0.045), and good neurological outcomes decreased from 8% to 4% (P=0.017). According to multivariate logistic regression analysis, good neurological outcomes (adjusted odds ratio, 0.299; 95% confidence interval, 0.116-0.772) were significantly lower after the onset of COVID-19. @*Conclusion@#With the outbreak of COVID-19, there have been many changes in the pre-hospital stages of out-of-hospital cardiac arrest patients, and the neurological outcomes have also deteriorated. This continued throughout the pandemic period.

Isolated Acetabular Liner Exchange for Polyethylene Wear and Osteolysis with Well-Fixed Metal Shell

BACKGROUND: The isolated liner and head exchange procedure has been an established treatment method for polyethylene wear and osteolysis when the acetabular component remains well fixed. In this study, the mid-term results of this procedure were evaluated retrospectively. METHODS: Among the consecutive patients operated on from September 1995, two patients (three hips) were excluded because of inadequate follow-up, and the results of remaining 34 patients (34 hips) were evaluated. There were 20 men and 14 women with a mean age of 49 years. A conventional polyethylene liner was used in 26 cases and a highly cross-linked polyethylene liner was used in eight cases. In three cases, the liner was cemented in a metal shell because a compatible liner could not be used. RESULTS: After a follow-up of 5 to 20.2 years, re-revision surgery was necessary in 10 cases (29.4%): in eight for wear and osteolysis at 55 to 101 months after liner exchange and in two for acetabular loosening at 1 and 1.5 years after liner exchange. Re-revision surgery included all component revision (four cases), cup revision (four cases), and liner exchange (two cases). In all re-revision cases, a conventional polyethylene liner was used initially. There was no failure in the cases in which a highly cross-linked polyethylene liner was used. CONCLUSIONS: The results of this study suggest that isolated acetabular liner exchange is a reasonable option for wear and osteolysis when the metal shell is well fixed. More promising long-term results are expected with the use of highly cross-linked polyethylene liners.

Histologic study of bone-forming capacity on polydeoxyribonucleotide combined with demineralized dentin matrix / 대한악안면성형재건외과학회지

BACKGROUND: This study examined the osteoinductive activity of demineralized dentin matrix (DDM) from human and polydeoxyribonucleotide (PDRN) for nude mice. METHODS: Twenty healthy nude mice, weighing about 15~20 g, were used for the study. DDM from human and PDRN were prepared and implanted subcutaneously into the dorsal portion of the nude mice. The nude mice were sacrificed at 1, 2, and 4 weeks after grafting and evaluated histologically by hematoxylin-eosin and Masson's trichrome staining. The specimens were also evaluated via a histomorphometric study. RESULTS: The DDM and PDRN induced new bone, osteoblasts, and fibroblasts in soft tissues. The histological findings showed bone-forming cells like osteoblasts and fibroblasts at 1, 2, and 4 weeks. New bone formation was observed in the histomorphometric study. In particular, the ratio of new bone formation was the highest at 2 weeks compared with the first week and fourth week. CONCLUSIONS: In this study, we showed that the PDRN used in this experimental model was able to induce bone regeneration when combined to the DDM.

Effect on bone formation of the autogenous tooth graft in the treatment of peri-implant vertical bone defects in the minip / 대한악안면성형재건외과학회지

BACKGROUND: The aim of this study was to evaluate the effect of autogenous tooth bone as a graft material for regeneration of bone in vertical bony defects of the minipigs. MATERIAL AND METHODS: Six minipigs were used in this study. Four molars were extracted in the right mandibular dentition and sent to the Korea Tooth Bank for fabrication of autogenous tooth bone. Ten days later, each extraction site was implanted with MS Implant Narrow Ridge 3.0 x 10mm fixture (Osstem, Seoul, Korea) after standardized 2mm-sized artificial vertical bony defect formation. Pineappleshaped Root-On type autogenous tooth bones were applied to the vertical defects around the neck area of the posterior three fixtures and the fore-most one was not applied with autogenous bone as a control group. Each minipig was sacrificed at 4, 8, 12 weeks after fixture installation and examined radiologically and histologically. Histological evaluation was done under light microscope with Villanueva osteochrome bone staining with semi-quantitative histomorphometric study. Percentage of new bone over total area (NBF) and bone to implant contact (BIC) ratio were evaluated using digital software for area calculation. RESULT: NBF were 48.15 +/- 18.02%, 45.50 +/- 28.37%, and 77.13 +/- 15.30% in 4, 8, and 12 weeks, respectively for experimental groups. The control group showed 37.00 +/- 11.53%, 32.25 +/- 26.99%, and 1.33 +/- 2.31% in 4,8,12 weeks, respectively. BIC ratio were 53.08 +/- 19.82%, 45.00 +/- 28.37%, and 75.13 +/- 16.55% in 4,8,12 weeks, respectively. Those for the control groups were 38.33 +/- 6.43%, 33.50 +/- 29.51 %, and 1.33 +/- 2.31% in 4, 8, 12 weeks, respectively. CONCLUSION: Autogenous tooth bone showed higher score than control group in NBF and BIC in all the data encompassing 4,8,12 weeks specimens, but statistically significant only 12 weeks data in both NBF and BIC.

Expression of vascular endothelial growth factor in oral squamous cell carcinoma

OBJECTIVES: The goal of this study was to determine the correlation of clinicopathological factors and the up-regulation of vascular endothelial growth factor (VEGF) expression in oral squamous cell carcinoma. MATERIALS AND METHODS: Immunohistochemical staining of VEGF and quantitative real-time polymerase chain reaction (RT-PCR) of VEGF mRNA were performed in 20 specimens from 20 patients with oral squamous cell carcinoma and another 20 specimens from 20 patients with carcinoma in situ as a controlled group. RESULTS: The results were as follows: 1) In immunohistochemical study of poorly differentiated and invasive oral squamous cell carcinoma, high-level staining of VEGF was observed. Significant correlation was observed between immunohistochemical VEGF expression and histologic differentiation, tumor size of specimens (Pearson correlation analysis, significance r>0.6, P<0.05). 2) In VEGF quantitative RT-PCR analysis, progressive cancer showed more VEGF expression than carcinoma in situ. Paired-samples analysis determined the difference of VEGF mRNA expression level between cancer tissue and carcinoma in situ tissue, between T1 and T2-4 (Student's t-test, P<0.05). CONCLUSION: These findings suggest that up-regulation of VEGF may play a role in the angiogenesis and progression of oral squamous cell carcinoma.

Osteomyelitis in an Osteopathia Striata with Cranial Sclerosis Patient / 대한악안면성형재건외과학회지

Osteopathia striata with cranial sclerosis (OS-CS) is characterized by linear bone dysplasia at the long bone radiographically and sclerotic change at the cranium. The purpose of this case report is to study the symptoms and treatments of osteomyelitis in a patient with OS-CS. A 41-year-old patient had pus discharge from a fistula at the mental region and increase in radiolucencies with sequestra in panoramic radiograph images. Computed tomography (CT) as well as radiograph images for the whole skeleton were taken. The patient was diagnosed with OS-CS. Sequestrectomy and fistulectomy were performed. The patient recovered and no relapse occurred within six months after surgery. For diagnosis of OS-CS, CT and additional radiograph images for the whole skeleton are required. Because of the increased bone density, this patient is prone to relapse after sequestrectomy. Therefore, the surgeon must minimize trauma with the least incision and exfoliation, and preoperative antibiotics.

Bone Induction by Demineralized Dentin Matrix in Nude Mouse Muscles / 대한악안면성형재건외과학회지

PURPOSE: This study examined the osteoinductive activity of demineralized human dentin matrix for nude mice. METHODS: Twenty healthy nude mice weighing about 15 to 20 g were used for study. Demineralized human dentin matrix was prepared and implanted into the dorsal portion of nude mice (subcutaneous), which were sacrificed at two, four, and eight weeks after demineralized dentin matrix grafting and evaluated histologically by H&E and Masson trichrome staining. The specimens were also evaluated histomorphometrically. RESULTS: The demineralized dentin matrix induced bone and cartilage formation independently in soft tissues. Histological examination showed bone-forming cells such as osteoblasts and fibroblasts at two, four, and eight weeks. CONCLUSION: These results suggest that demineralized human dentin matrix has osteoinductive ability, and is a good alternative to autogenous bone graft materials.

Analysis of Organic Components and Osteoinductivity in Autogenous Tooth Bone Graft Material

Clinical Study on the Alveolar Bone Repair Capacity of Dentin Matrix Block

Tooth-derived bone graft material

With successful extraction of growth factors and bone morphogenic proteins (BMPs) from mammalian teeth, many researchers have supported development of a bone substitute using tooth-derived substances. Some studies have also expanded the potential use of teeth as a carrier for growth factors and stem cells. A broad overview of the published findings with regard to tooth-derived regenerative tissue engineering technique is outlined. Considering more than 100 published papers, our team has developed the protocols and techniques for processing of bone graft material using extracted teeth. Based on current studies and studies that will be needed in the future, we can anticipate development of scaffolds, homogenous and xenogenous tooth bone grafts, and dental restorative materials using extracted teeth.

Bisphosphonates-related osteonecrosis of the jaw in Korea: a preliminary report

OBJECTIVES: 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. MATERIALS AND METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Bisphosphonates-related osteonecrosis of the jaw in Korea: a preliminary report

OBJECTIVES: 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. MATERIALS AND METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Clinical application of auto-tooth bone graft material

INTRODUCTION: Auto-tooth bone graft material consists of 55% inorganic hydroxyapatite (HA) and 45% organic substances. Inorganic HA possesses properties of bone in terms of the combining and dissociating of calcium and phosphate. The organic substances include bone morphogenetic protein and proteins which have osteoinduction capacity, as well as the type I collagen identical to that found in alveolar bone. Auto-tooth bone graft material is useful as it supports excellent bone regeneration capacity and minimizes the possibility of foreign body reaction,genetic diseases and disease transmission. MATERIALS AND METHODS: Implant placement combined with osteoinductive regeneration,preservation of extraction socket, maxillary sinus augmentation, and ridge augmentation using block type,powder type, and block+powder type autobone graft materialwere performed for 250 patients with alveolar bone defect and who visited the Department of Oral and Maxillofacial Surgery, College of Dentistry, Dankook University from September 2009 to August 2011. RESULTS: Clinical assessment: Among the 250 patients of auto-tooth bone graft, clinical assessment was performed for 133 cases of implant placement. The average initial stabilization of placed implants was 74 implant stability quotient (ISQ). Radiological assessment: The average loss of crestal bone in the mandible as measured 6 months on the average after the application of prosthesis load was 0.29 mm, ranging from 0 mm to 3.0 mm. Histological assessment: In the histological assessment, formation of new bone, densified lamellated bone, trabecular bones, osteoblast, and planting fixtures were investigated. CONCLUSION: Based on these results, we concluded that auto-tooth bone graft material should be researched further as a good bone graft material with osteoconduction and osteoinduction capacities to replace autogenous bone, which has many limitations.

Extraction Socket Preservation and Reconstruction Using Autogenous Tooth Bone Graft: Case Report

Clinical study of diagnosis and treatment of bisphosphonate-related osteonecrosis of the jaws

INTRODUCTION: Bisphosphonates is used widely for the treatment of the Paget's disease, multiple myeloma, bone metastases of malignant tumors with the prevention of pain and their pathological fracture. However, it was recently suggested that bisphosphonates related osteonecrosis of the jaw (BRONJ) is a side effect of bisphosphonate use. MATERIALS AND METHODS: Twenty-four individuals, who were referred to the Department of Oral and Maxillofacial surgery, Dankook University Dental Hospital, were selected from those who had exposed bone associated with bisphosphonates from January, 2005 to December, 2009 according to the criteria of American Association of Oral and Maxillofacial Surgeons (AAOMS) for BRONJ. The patients group consisted of 7 males and 17 females between the age of 46 to 78 years (average 61.8 years). Each patient had panoramic imaging, computed tomography (CT), whole body bone scanning performed for a diagnosis and biopsy sampling from the necrotizing tissue. C-terminal cross-linking telopeptide of type I collagen (CTX) level of patients who had undergone surgical intervention was measured 7 days before surgery. RESULTS: The main cause of bone exposure was post-extraction (15), chronic periodontitis (4), persistent irritation of the denture (3). Twenty people had undergone BRONJ treatment for two to eight months except for 4 people who had to maintain the bisphosphonates treatment to prevent a metastasis and bone trabecular pain with medical treatment. When the bisphosphonate treatment was suspended at least for 3 months and followed up according to the AAOMS protocols, the exposed necrotizing bones were found to be covered by soft tissue. CONCLUSION: Prevention therapy, interruption of bisphophonates for at least 3 months and cooperation with the physician for conservative treatment are the essential for treating BRONJ patient with high risk factors. The CTX level of BRONJ patients should be checked before undergoing surgical intervention. Surgical treatments should be delayed in the case of a CTX level <150 pg/mL.

Bone regeneration of the fluoridated hydroxyapatite and the bio-glass in the rabbit cranium defect model

INTRODUCTION: Hydroxyapatite (Ca10(PO4)6(OH)2, HA) is the main inorganic phase of human hard tissue that is used widely as the repair material for bones. When HA is applied to a bony defect, however, it can be encapsulated with fibrous tissue and float in the implanted area due to a lack of consolidation. Bioceramics as allogenic graft materials are added to HA to improve the rate and bone healing capacity. Fluoridated hydroxyapatite (Ca10(PO4)6(OH,F)2, FHA), where F- partially replaces the OH- in hydroxyapatite, is considered a good alternative material for bone repair owing to its solubility and biocompatibility. MATERIALS AND METHODS: This study was designed to determine the bone healing capacity of FHA newly produced as a nanoscale fiber in the laboratory. HA and FHA with bioglass was implanted in a rabbit cranium defect and the specimen was analysed histologically. RESULTS: 1. At 4 weeks, fibrous connective tissue and little bone formation was observed around the materials of the experimental group I implanted HA and bioglass. Newly formed bone was observed around the materials in the experimental group II implanted FHA and bioglass. 2. At 8 weeks, the amount of newly formed and matured bone was higher in experimental group II than in experimental group I and the control group. CONCLUSION: These results suggest that FHA and bioglass is a relatively favorable bone substitute with biocompatibility and better bone healing capacity than pure HA and bioglass.

Epidermal growth factor receptor overexpression and K-ras mutation detection in the oral squamous cell carcinoma

INTRODUCTION: Epidermal growth factor is a single-chain polypeptide consisting of 53 amino acids with potent mitogenic activity that stimulates the proliferation of a range of normal and neoplastic cells through an interaction with its specific receptor (epidermal growth factor receptor, EGFR). This interaction plays a key role in tumor progression including the induction of tumor cell proliferation. An increased EGFR copy number have been associated with a favorable response to EGFR tyrosine kinase inhibitors therapy. In contrast, K-ras mutations tend to predict a poor response to such therapy. The aim of this study was to determine the correlation between the clinicopathological factors and the up-regulation of EGFR expression and Kras mutations in oral squamous cell carcinoma. MATERIALS AND METHODS: This study examined the immunohistochemical staining of EGFR, K-ras mutation detection with peptide nucleic acid (PNA)-based real-time polymerase chain reaction (PCR) clamping in 20 specimens from 20 patients with oral squamous cell carcinoma. RESULTS: 1. In the immunohistochemical study of poorly differentiated and invasive oral squamous cell carcinoma, a high level of EGFR staining was observed. The correlation between immunohistochemical EGFR expression and histological differentiation, as well as the tumor size of the specimens was significant (Pearson correlation analysis, significance [r] >0.5, P<0.05). 2. In PNA-based real-time PCR clamping analysis, a K-ras mutation was not detected in all specimens. CONCLUSION: These findings suggest that the up-regulation of the EGFR may play a role in the progression and invasion of oral squamous cell carcinoma that is, independent of a K-ras mutation.

Guide bone regeneration using autogenous teeth: case reports

The authors installed implants combined with guided bony regeneration (GBR) using autogenous tooth bone graft material in the patients. In one patient, GBR and simultaneous implant placement were performed. In two patients, GBR was performed and the implants were placed after 6 months. All patients achieved favorable clinical outcomes. Excellent osteoconductive bony healing was observed in the 6 month histology examination after the bone graft.