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Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease and is strongly associated with obesity-related ectopic fat accumulation in the liver. Hepatic lipid accumulation encompasses a histological spectrum ranging from simple steatosis to nonalcoholic steatohepatitis (NASH), which can progress to cirrhosis and hepatocellular carcinoma. Given that dysregulated hepatic lipid metabolism may be an onset factor in NAFLD, understanding how hepatic lipid metabolism is modulated in healthy subjects and which steps are dysregulated in NAFLD subjects is crucial to identify effective therapeutic targets. Additionally, hepatic inflammation is involved in chronic hepatocyte damage during NAFLD progression. As a key immune signaling hub that mediates NF-κB activation, the IκB kinase (IKK) complex, including IKKα, IKKβ, and IKKγ (NEMO), has been studied as a crucial regulator of the hepatic inflammatory response and hepatocyte survival. Notably, TANK-binding kinase 1 (TBK1), an IKK-related kinase, has recently been revealed as a potential link between hepatic inflammation and energy metabolism. Here, we review (1) the biochemical steps of hepatic lipid metabolism; (2) dysregulated lipid metabolism in obesity and NAFLD; and (3) the roles of IKKs and TBK1 in obesity and NAFLD., Obesity: tracing the inflammation underlying liver disease A deeper understanding of the molecular processes underlying dysfunctional fatty-acid metabolism in nonalcoholic fatty liver disease (NAFLD) could help protect patients from severe liver damage. NAFLD is a common consequence of obesity, and severe disease can ultimately give rise to liver cancer or cirrhosis. Alan Saltiel of the University of California, San Diego, USA, and Jin Young Huh of Seoul National University, South Korea, have reviewed current knowledge of the mechanisms governing fatty acid metabolism in the liver, and how they are disturbed in obesity and NAFLD. The various IκB kinase (IKK) complexes and a protein known as TANK-binding kinase 1 (TBK1) play particularly prominent roles in the inflammatory response associated with NAFLD pathogenesis. Better insights into IKK- and TBK1-associated regulatory pathways could inform the development of new interventions for this currently untreatable condition.

RATIONALE Chronic obstructive lung disease (COPD) is a chronic progressive disease. Although smoking is the most important risk factor, 30% of COPD patients are never smokers, and environmental age...

Background Recent study suggested that combination therapy with pirfenidone and nintedanib had a manageable safety and tolerability profile in patients with idiopathic pulmonary fibrosis (IPF). However, safety and efficacy of combination therapy in real-world practice are unknown. We aimed to investigate safety and efficacy of combination therapy with pirfenidone and add-on nintedanib in patients with IPF. Methods Clinical data of IPF patients treated with pirfenidone and add-on nintedanib were retrospectively analyzed. Adverse events and lung function declines were compared before and after treatment with nintedanib. Results Nineteen patients with IPF underwent combination therapy. At the beginning of treatment, the mean age of all patients was 70.4 years and 84.2% were male. The median follow-up period was 7.6 months. All patients received add-on nintedanib during treatment with pirfenidone at a stable dose (mean dose: 1768.4 ± 137.6 mg/day, mean duration 32.0 ± 11.2 months ). Most common adverse events attributable to nintedanib were diarrhea (31.6%), anorexia (21.1%) and dyspepsia (15.8%). In 3 patients (15.6%), one of the antifibrotic agents was discontinued due to adverse events (pirfenidone in 2, and nintedanib in 1 due to anorexia or dyspepsia). In 13 patients with serial lung function data before and after treatment, decline rate in forced vital capacity (FVC) significantly reduced (-12.4 ± 2.0 ml/month [before] vs. -10 ± 4.6 ml/month [after], p < 0.001) after treatment with nintedanib. Decline in FVC for 3 months also significantly reduced (-154 mL [before] vs. 93 mL [after], p=0.002) after treatment (Figure 1). Conclusions Our data suggests that the combination therapy with pirfenidone and add-on nintedanib had a manageable safety profile, and might be more effective than monotherapy

Adipose tissue macrophages (ATMs) have important roles in the regulation of inflammatory responses and insulin resistance in obesity. A new study reports that a subpopulation of ATMs, TIM4+ resident ATMs, modulate adipocyte size via platelet-derived growth factor-CC production during development and diet-induced adipose tissue expansion.

The steep rise in thyroid cancer observed in recent decades has caused an increase in the population of long-term thyroid cancer survivors. Other than recurrences of cancer, the long-term health consequences of surviving thyroid cancer, particularly metabolic syndrome, have not yet been determined. The aim of this study was to estimate the risk of metabolic syndrome in thyroid cancer survivors.Population-based data from the Korean National Health and Nutrition Examination Survey (KNHANES) were used for the analysis. The data of KNHANES IV-VI from 2007-2014 were obtained. After excluding subjects who were under 19 years old, whose fasting interval was less than 8 hours, and whose data for predefined variables including metabolic syndrome components were incomplete, 34,347 subjects were analyzed. The incidence of metabolic syndrome and its components were evaluated in three groups: subjects with no history of thyroid cancer, subjects diagnosed with thyroid cancer within 3 years of the survey date, and subjects diagnosed more than 3 years before the survey date.Thyroid cancer diagnoses were made within 3 years of the survey date for 95 subjects (group 1, short-term survivors) and more than 3 years earlier than the survey date for 60 subjects (group 2, long-term survivors). Metabolic syndrome was frequently observed with clinical significance (odds ratio [OR] 1.986 [95% confidence interval [CI] 1.0-3.70], p = 0.030) in short-term survivors compared with subjects with no thyroid cancer history. Risks for having high blood pressure and high fasting glucose were estimated to be higher in the short-term survivor group (OR 2.115 [CI 1.23-3.64], p = 0.006 and OR 1.792 [CI 1.03-3.11], p = 0.038, respectively). No significant associations were noticed in the long-term survivor group when compared with the group with no thyroid cancer history.Risks for metabolic syndrome, especially high blood pressure and high fasting glucose, were increased in short-term survivors of thyroid cancer but not in long-term survivors when compared with subjects with no history of thyroid cancer.

BACKGROUND AND PURPOSE Chopsticks are a primary eating utensil in East Asia, but systematic assessments of chopsticks skills in parkinsonian disorders is lacking. We aimed to identify any differences in chopsticks skills in the early stages of Parkinson's disease (PD) and atypical parkinsonism (AP), including progressive supranuclear palsy (PSP), multiple system atrophy (MSA), and corticobasal syndrome (CBS). METHODS We consecutively recruited 111 patients with PD and 74 with AP (40 with PSP, 30 with MSA, and 4 with CBS) who were in a drug-naive state. The motor and cognitive functions of the patients were evaluated using a standardized protocol. Everyday chopsticks skills were evaluated using a chopsticks questionnaire developed in-house. The chopsticks skills test (CST) involved counting the number of pills that the subject was able to carry using chopsticks between two dishes separated by 20 cm within 20 seconds. RESULTS Patient responses to the questionnaire indicating poor chopsticks skills ("I cannot pick up some of the food items" or "I cannot use chopsticks anymore") were present in 23.0% of AP patients and 30% of PSP patients, compared to only 5.6% of PD patients [odd ratio (OR)=5.07 and OR=7.29, p≤0.001 in both]. The performance in the CST was worse in PSP than in PD (p

17알파 수산화효소 결핍증은 고혈압, 남성 환자에서의 가성남녀한몸증 및 여성 환자에서의 성적 유치증 및 일차무월경을 유발하는 드문 질환이다. 염류 코르티코이드에 의한 고혈압과 감별하여야 하며, 특히 알도스테론 수치가 높은 17알파 수산화효소 결핍증 환자에서는 성호르몬과 11-디옥시코르티코스테론, 코르티코스테론을 포함한 부신호르몬에 대한검사를 통해 진단에 도움을 받을 수 있다. 저자들은 혈압이 조절되지 않아 내원한 32세 여자에서 부신 선종 절제술 이후에도 고혈압이 지속되어, 남성 남녀한몸증의 병력을 고려하여 추가적인 호르몬 검사를 시행한 결과 17알파 수산화효소결핍증이 진단된 1예를 경험하였기에 문헌고찰과 함께 보고하는 바이다.

Mercury is traditionally used as a dye for making amulets in Korea. Inhaling the vapor produced by burning mercury damages major organs, such as the lungs, kidneys, and brain. We herein present a case of a 41-year-old man who complained of abdominal pain and dyspnea. A chest X-ray and computed tomography scan showed infiltration in both upper lung lobes. A thorough medical history revealed that the patient had made amulets prior to developing symptoms, and blood and urine tests confirmed elevated levels of mercury. Dimercaptosuccinic acid was used to chelate the mercury, and methylprednisolone was used to treat the acute lung injury. No kidney or nervous system complications were detected during follow-up. Inhalation of mercury vapor should be suspected in patients with acute lung injury involving both upper lobes. (Korean J Med 2015;89:563-566)

The aim of this study was to evaluate the use of autogenous bone in combination with platelet-enriched fibrin glue as a grafting material for maxillary sinus augmentation with simultaneous implant placement in dogs.The mucous membranes of 12 sinuses in 6 dogs were elevated bilaterally. In the right sinus, autogenous bone mixed with platelet-enriched fibrin glue was grafted into the space between the membrane and the sinus wall. In the left sinus, autogenous bone alone was grafted as a control. At the same time, 2 dental implants were inserted into the grafting material through the maxillary sinus floor. The animals were killed 6 months after surgery.The mean bone-implant contact was 40.5% on the fibrin glue side and 32.3% on the control side (P.05). The mean height of newly formed bone in the augmented area was 12.2 mm on the fibrin glue side and 10.7 mm on the control side (P.05).The results indicate that the use of autogenous bone mixed with platelet-enriched fibrin glue can achieve results superior to those for grafts of autogenous bone alone. The specific improvements of this technique include enhanced osseointegration of dental implants and increased height of new bone.

Objective The aim of this study was to investigate whether dental implant exposure to the maxillary sinus cavity increases the risk of maxillary sinus complications. Study design An implant was placed bilaterally in the maxillary sinus of 8 adult female mongrel dogs in a way that it penetrated the bone and mucous membrane of the maxillary sinus floor to the extent of 2 mm, 4 mm, or 8 mm. The implants were left in place for 6 months. Results Radiographic and histologic examinations did not show any signs of pathologic findings in the maxillary sinus of the 8 dogs. Conclusion This study indicates that implant protrusion into the maxillary sinus cavity is not related to the development of sinus complications in canines.

Summary Aim The aim of this study was to develop a novel artificial nerve conduit and to evaluate its efficiency based on the promotion of peripheral nerve regeneration in rabbits. Material and methods The nerve conduit was made of a poly (l-lactide- co -glycolic acid)-coated collagen tube filled with collagen gel. The conduits were implanted into a 15mm gap in the peroneal nerves of five rabbits. On the contralateral side, the defects were bridged with collagen-filled vein grafts. Results Twelve weeks postoperatively nerve regeneration was superior to the vein graft in the PLGA-coated collagen tube, both morphologically and electrophysiologically. Conclusion The results indicate the superiority of the PLGA-coated collagen tube over vein grafts. Furthermore, they show that entubulation repair with this type of tube can support nerve regeneration over a nerve gap distance of at least 15mm.

Objective The purpose of this study was to determine the minimum size defect in a canine mandible that would not spontaneously heal during the dog's natural life (the critical size defect). Study design Sixteen adult female mongrel dogs underwent continuity resection on both sides of the mandible to create bilateral defects. In 8 dogs, mandibular defects ranging from 5 to 20 mm were created with periosteal resection. In the other 8 dogs, mandibular defects ranging from 30 to 60 mm were created preserving the periosteum. The dogs were then killed at 6 months and the defects examined using radiographs and histologic analysis. Results When the periosteum was removed, mandibular defects greater than 15 mm failed to heal across the entire defect. However, when the periosteum was preserved, mandibular defects needed to be greater than 50 mm in order to fail to heal. Conclusion The critical size defect in a canine mandible model is 15 mm when the periosteum is removed and 50 mm when the periosteum is preserved.

Objective The aim of this study was to decide whether use of bicortical screw fixation provides sufficient stability to dispense with intermaxillary fixation (IMF). Study design Eighty-six patients who had undergone surgical setback of the mandible using bilateral sagittal split ramus osteotomies were examined. Group 1 (15 patients) received miniplate fixation with IMF for 6 weeks, and group 2 (71 patients) received bicortical screw fixation and immediate postoperative function. The 2 groups were evaluated radiographically for postsurgical changes of the pogonion 24 months postoperatively. Results There was no significant difference in the magnitude of the relapse between the 2 groups over the 24-month postoperative period. Conclusion The use of bicortical screw fixation after sagittal split setback of the mandible provides sufficient stability to dispense with IMF.

Previous studies have shown that the presence of unerupted mandibular third molars predisposes the mandible to angle fractures. This study attempted to relate the presence of unerupted mandibular third molars with the incidence of condyle fractures. The authors compared the proportion of fractures in 439 patients who had unerupted third molars or no unerupted third molars. Fractures at the condylar region showed a significantly higher incidence in patients without unerupted third molars than in those patients with unerupted third molars. This study provides solid clinical evidence to suggest that the removal of unerupted mandibular third molars predisposes the mandible to condyle fractures.

We have developed a reliable method of microneural anastomosis using cyanoacrylate adhesives. This method involves overlapping the epineuriums of the two nerve ends and then applying two or three microdrops of cyanoacrylate adhesive on the surface of the epineurium just where the epineuriums overlap. The sciatic nerves of Sprague-Dawley rats were transected and repaired either with 10-0 nylon sutures or by using the described method. Histological evaluation showed no significant difference in the outcome of nerve regeneration between the two groups. It was concluded that the cyanoacrylate repair deserves to be considered as an alternative to the conventional suture technique in microneural anastomosis.

Introduction: Vertical augmentation of the alveolar ridge is necessary for extensive resorption of the alveolar ridge. Aim: To evaluate treatment outcome after alveolar ridge augmentation by a sandwich osteotomy combined with an interpositional allograft. Patients and Methods: The deficient alveolar ridges were augmented by a sandwich osteotomy combined with bovine collagen matrix as an interpositional allograft placed between the basal bone and the osteotomized fragment without fixation. Standardized lateral cephalographs were taken of nine patients, before surgery, immediately postoperatively and 3 months after augmentation to evaluate the level of augmentation, bone loss and stability of the osteotomized fragment. Results: The augmentation ranged between 8.4 and 11.0 mm (mean 9.8 mm). Bone resorption in the crestal bone height ranged from 1.5 to 3.0 mm (mean 2.1 mm) after 3 months. Bone resorption in thickness of the osteotomized fragment ranged from 0.3 to 2.0 mm (mean 1.0 mm). Conclusion: Although there was some resorption of the superior and anterior parts of the reconstructed alveolar process, it was concluded that this procedure of augmentation is safe.

Introduction: Little attention has been paid to the mechanical effects of fracture reduction forceps. Aim: This study aims to evaluate the stress patterns within the fractured mandible generated by reduction forceps. Material and Methods: Thirty-six mandibular models were fabricated using a photoelastic resin. Each of the three sets of mandibular models was osteotomized according to one of three different fracture types. After reducing the cut segments, reduction forceps were placed into different engagement holes to compress the segments. Photoelastic stress analysis was used to visualize the stress patterns within the fractured mandibular models as generated by the reduction forceps. Results: In the case of symphyseal or parasymphyseal fractures, an optimum distribution of stresses over the fracture site was achieved when placing the reduction forceps more than 12 mm away from either side of the fracture line, between the midway level of the mandibular height (bisecting the mandible) and 5 mm below this level. In the case of body fractures, optimum stress distribution was achieved when the reduction forceps were placed more than 16 mm from the fracture line at the midway level. Conclusion: Correct use of the reduction forceps helps to provide a precise three-dimensional reduction for mandibular fractures.

The purpose of this study was to evaluate the long-term radiological results obtained with open reduction and fixation of unilateral mandibular condyle fractures in 10 patients. CT images taken at the end of the follow-up period (average of 22 months, range 7 to 33 months), were traced and digitized, and the position and morphology of the fractured condylar process was statistically compared with those of the contralateral non-fractured condylar process in the coronal, transverse and sagittal planes. Little difference was observed in the position or morphology of the condylar process in the operated and non-fractured joints. This study shows that it is possible to anatomically reduce fractured condyles, and thereby to avoid postoperative disadvantageous joint changes.

Dear Editor, Ataxia with oculomotor apraxia type I (AOA1) is a recessively inherited ataxic disorder that is characterized clinically by the childhood onset of progressive cerebellar ataxia, oculomotor apraxia (OMA), and peripheral axonal sensorimotor neuropathy.1 Dystonia, chorea, and cognitive impairment are commonly associated symptoms, and hypoalbuminemia and hypercholesterolemia are often observed.2 AOA1 is caused by mutations of the gene encoding aprataxin (APTX).3 AOA1 has not been reported previously in Korea.5 The first case of AOA1 in Korea is presented here. In this patient, who did not exhibit OMA but had bilateral gaze-evoked nystagmus, the condition was caused by compound heterozygous mutations of APTX. A 32-year-old man presented with slowly progressive gait disturbance and unsteadiness that developed at the age of 14 years. He was the second child of healthy unrelated Korean parents without a family history of gait disturbance. He was diagnosed as having cerebellar atrophy of unknown cause at the age of 17 years. His ataxic gait had progressively deteriorated and he had become confined to a wheelchair 2 years prior to presentation. A physical examination revealed pes cavus but no scoliosis or other musculoskeletal deformity. A neurological examination revealed mild cerebellar dysarthria without dysphagia. His limb motor powers were normal, as were light touch, pinprick, temperature, and pain sensations. However, his vibration and positional senses were decreased in the lower limbs, his deep tendon reflexes were hyporeflexic in all the limbs, Babinski signs were absent bilaterally, and he had bilateral upper and lower limb dysmetria and truncal ataxia. The patient was unable to stand still without assistance. His ranges of extraocular movement were full in all directions, and he did not exhibit OMA on reflexive saccades testing, but his optokinetic nystagmus was impaired. He presented gaze-evoked nystagmus in all directions. His Mini-Mental State Examination score was 30. The results of laboratory tests were unremarkable except for hypercholesterolemia (217 mg/dL), hypoalbuminemia (3.3 g/dL), and mildly elevated alpha-fetoprotein (7.05 ng/mL). A nerve conduction study and electromyography revealed sensorimotor axonal polyneuropathy, and brain magnetic resonance imaging revealed pure cerebellar atrophy without involvement of the pons, medulla oblongata, midbrain, or cerebral cortex (Fig. 1A and B). Sanger sequencing after PCR amplification of APTX revealed compound heterozygous mutations involving the deletion of two nucleotides (c.359_360delAC, p.Asp120Lysfs2) in exon 3, and a missense mutation (c.617C>T, p.Pro206Leu, rs121908131) in exon 5 (Fig. 1C). While the mutation of c.359_360delAC is novel, c.617C>T is a known pathogenic mutation. The patient’s father is a carrier of the single heterozygous mutation (c.617C>T); we were unable to perform genetic testing on his mother. While Friedreich’s ataxia is the most frequent cause of autosomal recessive ataxia in the Caucasian population,6 it is rare in Korea and Japan.5,7 Before discovery of the APTX mutation, AOA1 was known as early-onset ataxia with OMA and hypoalbuminemia (EAOH) in Japan Minwoo Lee Nan Young Kim Jin Young Huh Young Eun Kim Yun Joong Kim

Florid cemento-osseous dysplasia (FCOD) is a benign, non-neoplastic lesion characterized by multiple sclerosing masses only within jawbones. It is frequently confused with chronic diffuse sclerosing osteomyelitis (CDSO) in the literature. Two cases of FCOD are examined to determine the characteristics of their calcifying tissues. The first case was non-infected, while the second case was severely infected, displaying the typical features of CDSO in clinico-radiologic findings. The infected FCOD case showed large bacterial colonies in the main lesion with rare inflammatory reaction. The globular cementum-like materials of FCOD looked like woven bone and showed increased positive reaction to Alcian blue stain, of which peripheral margin was strongly positive for the antibody of ameloblastin, and weakly positive for the antibodies of bone morphogenetic protein-2 and -4. In the immunostains of matrix metalloprotein-3, -9, -10, and transforming growth factor-alpha, macrophage infiltration in the FCOD lesion were rarely observed. These data suggest that the cementum-like materials of FCOD contain various matrix proteins, and that the cementum-like materials are relevant to the overgrowth of the bacterial colonies by the inhibition of regional inflammatory reactions.

Objective The aim of this study was to evaluate the combined use of autogenous bone and platelet-enriched fibrin glue as grafting material for vertical alveolar ridge augmentation with simultaneous implant placement in a canine alveolar ridge defect model. Study design In 6 mongrel dogs, bilateral vertical alveolar ridge defects were created in the mandible. After 3 months of healing, 2 dental implants were placed in each defect of the mandible, creating 6-mm supra-alveolar peri-implant defects. The 2 implants per defect were subjected to surgical treatments involving either a combination of autogenous bone grafts and platelet-enriched fibrin glue, or a conventional flap procedure only (control). After a healing period of 6 months, the dogs were humanely killed for histological and histometric analyses. Results Implant placement alone produced limited vertical alveolar height (0.6 ± 0.4 mm). However, alveolar augmentation including a combination of autogenous bone grafts and platelet-enriched fibrin glue with simultaneous implant placement resulted in alveolar ridge augmentation amounting to 4.2 ± 1.0 mm, comprising 63% of the defect height. New bone-implant contact was 40.5% in the defects treated with combined autogenous bone grafts and platelet-enriched fibrin glue, and was 48.4% in the resident bone; this difference was not statistically significant. Conclusion The present study demonstrates that vertical alveolar ridge augmentation using autogenous bone grafts and platelet-enriched fibrin glue with simultaneous implant placement might effectively increase vertical alveolar ridge height and allow for an acceptable level of osseointegration.

Objective The purpose of this study was to evaluate the effects of autogenous bone grafts and platelet-enriched fibrin glue in the treatment of peri-implantitis. Study design Thirty-six screw-type commercially pure titanium implants with rough acid-etched surfaces were inserted into 6 mongrel dogs 3 months after extraction of mandibular premolars. After 3 months of healing, peri-implantitis was induced by placing gauze and wire around the implants. Once peri-implantitis was created, surgical treatments involving a combination of autogenous bone grafts and platelet-enriched fibrin glue, autogenous bone grafts alone, or a conventional flap procedure only (control) were carried out. Six months later, biopsies of the implant sites were taken and prepared for ground sectioning and analysis. Results The amount of reosseointegration was significantly higher in peri-implantitis defects treated with combined autogenous bone grafts and platelet-enriched fibrin glue as compared with the other 2 treatment procedures. A mean bone-to-implant contact of 50.1% was obtained in the peri-implantitis lesions treated with combined autogenous bone grafts and platelet-enriched fibrin glue. The corresponding values for the autogenous bone grafts and control groups were 19.3% and 6.5%, respectively. Conclusion The present study demonstrates that surgical treatment involving the combined use of autogenous bone grafts and platelet-enriched fibrin glue might effectively promote reosseointegration in lesions resulting from peri-implantitis.

The activity of several growth factors on peripheral nerve regeneration is reported. Autologous fibrin glue contains a large number of platelets, which release significant quantities of growth factors. In order to understand the role of autologous fibrin glue in peripheral nerve regeneration, a 15-mm rabbit peroneal nerve defect was repaired using a vein graft filled with autologous fibrin glue. Axonal regeneration was examined using histological and electrophysiological methods. The extent of axonal regeneration was superior when treated with autologous fibrin glue. Our data suggest that fibrin nets formed by fibrinogen, in combination with growth factors present in autologous fibrin glue, might effectively promote peripheral nerve regeneration in nerve defects.

Various miniplate fixation techniques were studied in dogs to determine whether the use of miniplate fixation provides sufficient stability in mandibular continuity defects. Continuity resections measuring 15 mm were made on the mandibles of 16 dogs and were bridged using 4 miniplate fixation techniques, each replicated 4 times. All dogs were placed on a normal diet throughout the postoperative period. Clinical and radiological examinations were carried out 6 weeks later. We found that the group with both double miniplates and bicortical screws was stable, whereas the groups utilizing either a single miniplate or monocortical screws were not. The results of this study indicate that using a combination of double miniplates and bicortical screws to bridge defects after mandibular resection produces stable and predictable results.

Objective The aim of this study was to examine the ability of platelet-enriched fibrin glue to enhance bone formation in critically sized defects in the dog mandible. Study design Seven adult female mongrel dogs underwent continuity resections on both sides of the mandible; 1 defect was reconstructed with the original particulate bone mixed with platelet-enriched fibrin glue, and as a control the contralateral defect was reconstructed with the original particulate bone alone. Results Biopsies after 6 weeks showed that the addition of platelet-enriched fibrin glue enhanced new bone formation in the autogenous bone grafts. Conclusion Our data suggest that fibrin nets formed by fibrinogen, in combination with growth factors present in platelet-enriched fibrin glue, might effectively promote bone healing at bone graft sites.

Sinus lift procedures depend greatly on fragile structures and anatomical variations. These procedures may cause sinus membrane perforations, which can lead to graft infection and early failure. The aim of this study was to assess the efficacy of autologous fibrin glue in the management of large perforations of the maxillary sinus membrane occurring during sinus lifts. After elevating the sinus membrane in the bilateral maxillary sinuses of 6 adult female mongrel dogs, a laceration (about 2.0 cm in length) was made in the membrane and either repaired with autologous fibrin glue or covered with a bioabsorbable collagen membrane as a control. Wounded areas were biopsied 2 weeks after the operation. Wounds repaired with autologous fibrin glue showed newly formed continuous epithelium across the previous perforation site. However, extensive fibrosis, inflammatory infiltration, and absent epithelium were observed in wounds treated with the collagen membrane control. Our results support the clinical use of autologous fibrin glue for repairing sinus membrane perforations.

Summary Introduction Sinus lift procedures depend greatly on fragile structures and anatomical variations. The procedure may cause sinus membrane perforations, which can lead to graft infection and early failure. Aim To assess the efficacy of cyanoacrylate adhesive in the management of large perforations of the maxillary sinus membrane during sinus lifts. Material and methods Six rabbits were used in the study. Sinus membrane perforations (about 1.5 cm in length) were repaired with cyanoacrylate adhesive on one side of the maxillary sinus. On the contralateral side, an identical laceration was not repaired. Histological evaluation was performed 2 weeks after the operation. Results Wounds repaired with cyanoacrylate adhesive showed newly formed continuous epithelium across the previous perforation site and there was sinusitis on the contralateral side. Conclusion These results support the clinical use of cyanoacrylate adhesive for repairing sinus membrane perforations.

The aim of this study was to determine whether or not the use of the mandibular angle reduction forceps decreases the incidence of post-operative complications. Forty-six patients, who presented with mandibular angle fractures with a displacement or dislocation, were randomly divided into two treatment groups. Both groups underwent an open reduction with a single upper border miniplate and screw fixation. For 23 patients, the mandibular angle reduction forceps was used to aid in fracture reduction, and for 23 patients, the reduction of the fracture was achieved using IMF. The post-reduction radiographs showed that the reduction forceps group had a higher proportion of precise anatomic alignment of fracture than those in the IMF group. In addition, the former group showed a lower rate of post-operative complications, as compared to the latter group. This study found that the use of the mandibular angle reduction forceps is an important factor for decreasing the incidence of post-surgical complication.

This paper describes a new technique for microvascular anastomosis, which involves the overlapping of the adventitias of the two ends of a severed blood vessel, and then painting a cyanoacrylate adhesive on the outer surface of the vessel around the anastomosed part. Sixteen anastomoses were performed in both radial arteries and cephalic veins in eight dogs. All vessels were patent without thrombus. The described method of anastomosis was faster and easier to perform than the conventional suture anastomosis. Histologic studies revealed that the adhesive did not flow into the lumen, and that normal healing of the endothelium and of the internal elastic lamina occurred across the anastomotic site, even though the adhesive remained on the adventitial side of the vessel at 4 weeks. This technique deserves to be considered as an alternative to conventional suture anastomosis.

The role of cultured bone marrow stromal cells (BMSCs) in peripheral nerve regeneration was examined using an established rabbit peroneal nerve regeneration model. A 15-mm peroneal nerve defect was bridged with a vein filled with BMSCs (1×10 6 ), which had been embedded in collagen gel. On the contralateral side, the defect was bridged with a vein filled with collagen gel alone. When the regenerated tissue was examined 4, 8 and 12 weeks after grafting, the number and diameter of the myelinated fibers in the side with the BMSCs were significantly higher than in the control side without the BMSCs. This demonstrates the potential of using cultured BMSCs in peripheral nerve regeneration.

In this study, we evaluated the effect of platelet-rich plasma (PRP) on bone regeneration in an autogenous bone graft in a canine model. The mandibular premolar teeth had been bilaterally extracted previously, and the ridges had been allowed to heal for 3 months. After this period, continuity resection was performed on both sides of the mandible. One defect (the PRP group) was reconstructed with the original particulate bone mixed with PRP. As a control, the contralateral defect (non-PRP group) was reconstructed with the original particulate bone alone. Biopsies after 6 weeks showed lower levels of bone formation in the PRP group than in the non-PRP group, and fluorescence microscopy revealed a delay in the remodelling of grafts loaded with PRP. These findings suggest that the addition of PRP does not appear to enhance new bone formation in autogenous bone grafts.

Summary Aim Several injectable materials have been used as osteogenic bone substitutes. However, none has gained universal acceptance. This study was performed to investigate whether or not chitosan-alginate gel/mesenchymal stem cells/bone morphogenetic protein-2 composites are potentially injectable materials for new bone formation. Material and methods The composites were injected into the subcutaneous space on the dorsum of nude mice to investigate new bone tissue formation. The composites were examined histologically over a 12-week period. Results The composites injected into the mouse were able to stimulate new bone formation, which was trabecular in type. Conclusions This study showed that chitosan-alginate gel/MSCs/BMP-2 composites could become clinically useful injectable materials to generate new bone.

This study was undertaken to evaluate the biomechanical stability of various miniplate fixation techniques in varying degrees of atrophy and to determine optimal fixation techniques for fractures of the atrophic edentulous mandible. A total of 78 bovine ribs were randomly divided into 13 groups of six each; one non-atrophic group and twelve atrophic groups. Each one of the 13 sets of six ribs was formed based on the vertical dimension (40, 20, 15 or 10 mm) and osteotomized. The segments so produced were then reduced and fixed using various miniplate fixation techniques. The stability of various miniplate fixations in ribs showing varying degrees of atrophy (10, 15 and 20 mm) was compared with that of one miniplate fixation in non-atrophic ribs (40 mm), used as a standard. Atrophic groups utilizing single miniplate were significantly less stable than the non-atrophic group, whereas atrophic groups fitted with double miniplates, such as two 4-hole or two 6-hole miniplates, were significantly more stable than the non-atrophic group. The two miniplate fixation technique is recommended for the provision of adequate fracture site stability when open reduction is indicated in cases of atrophic edentulous mandibular fractures.

【1. Objective. The aim of this study was to investigate whether dental implant exposure to the maxillary sinus cavity increases the risk of maxillary sinus complications. 2. Study design. An implant was placed bilaterally in the maxillary sinus of eight adult female mongrel dogs in a way that it penetrated the bone and mucous membrane of the maxillary sinus floor to the extent of 2 mm, 4 mm, or 8 mm. The implants were left in place for six months. 3. Results. Radiographic and histologic examinations did not show any signs of pathologic findings in the maxillary sinus of the eight dogs. 4. Conclusion. This study indicates that implant protrusion into the maxillary sinus cavity is not related to the development of sinus complications.】