Maxillofacial Fractures Associated With Interpersonal Violence.

Interpersonal violence is a major cause of maxillofacial fractures. The aim of this study was to analyze the characteristics of these fractures associated in an effort to develop more effective management. The clinical records and radiographs of 272 patients with maxillofacial fractures associated with interpersonal violence collected during a 36-year period were retrospectively analyzed. Two hundred and nineteen patients were male (80.5%) and 53 (19.5%) were female. The patients ranged in age from 1 to 77 years. Two hundred and two patients (74.3%) were aged 10 to 29 years. The injury was the result of impact by a fist/hand/elbow in 224 patients (82.3%). The fracture site was the mandible in 191 patients (70.2%), the midface in 78 (28.7%), and both sites in 3 (1.1%). One hundred and eight (39.6%) of 273 mandibular fractures were in the angle, 75 (27.5%) were in the symphysis, and 90 (33.0%) were at other sites. Forty-three (53.1%) of 81 fractures in the midface were in the zygoma, 19 (23.5%) were in the maxilla, and 19 (23.5%) were at other sites. Fractures were more common on the left side. Nine patients (3.3%) also had injuries at other body sites. Ninety-five patients (34.9%) were treated by maxillomandibular fixation, 84 (30.9%) by open reduction and internal fixation, 59 (21.7%) by observation, 14 (5.1%) by intramaxillary splinting, 14 (5.1%) by transcutaneous reduction, and 6 (2.2%) by other procedures. Interpersonal violence-related maxillofacial fractures have characteristic features, especially with regard to site and laterality.

Trends and characteristics of maxillofacial fractures sustained during sports activities in Japan.

BACKGROUND/AIM: Sports activity increases the risk of maxillofacial fractures. The aim of this study was to analyze trends and characteristics of maxillofacial fractures sustained during sports activity to develop more effective treatments and possibly to prevent injury. MATERIALS AND METHODS: Data of 248 patients with maxillofacial fractures sustained during sports activity were retrospectively analyzed based on their clinical records and radiographs. RESULTS: The patients were 226 males (91.1%) and 22 females (8.9%). Their ages ranged from 6 to 70 years and the majority were in their second decade. The fractures were sustained in various sports which included baseball in 85 patients (34.3%), rugby in 40 (16.1%), soccer in 30 (12.1%), softball in 22 (8.9%), golf in 10 (4.0%), hockey in 8 (3.2%), combat sports in 28 (11.3%), and others in 29 (11.7%). The cause of injuries was collision with another player in 97 patients (39.1%), hit by a ball in 89 (35.9%), intended attack in 20 (8.1%), hit by equipment of another player in 15 (6.0%), a fall in 14 (5.6%), and collision with ground equipment in 13 (5.2%). The site of fractures was the mandible in 145 patients (58.5%), midface in 100 (40.3%), and both in 3 (1.2%). Among 210 fracture sites in the mandible, 77 (36.6%) were in the angle, 68 (32.4%) in the symphysis, and 65 (30.9%) in others. Among 103 fractures in the midface, 58 (56.3%) were in the zygoma, 26 (25.2%) in alveolar bone, and 19 (18.4%) in others. Treatment was observation in 67 patients (27.0%), maxillomandibular fixation in 64 (25.8%), open reduction and internal fixation in 63 (25.4%), intramaxillary splinting in 40 (16.1%), transcutaneous reduction in 10 (4.0%), and other procedures in 4 (1.6%). CONCLUSION: Maxillofacial fractures sustained during sports activity showed characteristic features dependent on the type of sport and cause of injury.

Computed Tomography-Based 3-Dimensional Finite Element Analyses of Various Types of Plates Placed for a Virtually Reduced Unilateral Condylar Fracture of the Mandible of a Patient.

PURPOSE: This study was performed to evaluate stresses in various types of plates placed for a virtually reduced unilateral condylar fracture of the mandible using computed tomography-based 3-dimensional finite element (FE) models of a patient to select the optimal plate system. MATERIALS AND METHODS: A computed tomography-based FE model of the mandible of a patient with a unilateral condylar fracture was constructed. The fracture was virtually reduced and fixed with 1 straight titanium plate; 2 straight titanium plates; 2 straight poly-L-lactic acid plates; and 4-hole (box), 5-hole (strut), and 7-hole (lambda) condylar plates. Stresses developing in these plates were analyzed by applying 478.1 N of bite force at the first molar of the contralateral side of the mandible. RESULTS: The magnitudes of tensile stress were within the tensile strength in all types of plates. However, the magnitudes of compressive stress in 1 straight titanium plate and 2 straight poly-L-lactic acid plates were beyond the compressive strength. The tensile and compressive stresses of the 5-hole (strut) plate were the smallest among the 3 types of condylar plates. CONCLUSIONS: Fixation by 2 straight titanium plates or any type of condylar plate was biomechanically indicated for the condylar fracture of this patient. Among these plates, the 5-hole (strut) plate was considered optimal. FE analysis is useful in selecting the optimal fixation method in the individual patient.

Biomechanical analysis of poly-L-lactic acid and titanium plates fixated for mandibular symphyseal fracture with a conservatively treated unilateral condylar fracture using the three-dimensional finite element method.

The purpose of this study was to investigate stress on poly-L-lactic acid (PLLA) plates with a thickness of 1.4 mm and titanium plates with a thickness of 1.0 and 1.4 mm placed for mandibular symphyseal fractures with or without conservatively treated, unilateral condylar fractures using finite element analysis. The symphyseal fracture region was defined by the following three conditions: the defect, the callus, and the contact condition. Stress on the plates was analyzed by an applying occlusal force of 478.1 N on the first molar of the non-condylar fracture side. In the model of isolated symphyseal fracture, the maximal stresses were below the material strength in all plate types and conditions. In the models with condylar fracture, the maximal stresses on these plates were much higher than those in the models of isolated symphyseal fracture, especially for the defect condition. Although the maximal stresses on all types of plates in the contact condition were below the material strengths, some of those in the defect condition were higher than these strengths. These results suggest that a PLLA plate can theoretically withstand stress under good reductions of symphyseal fractures, even for condylar fractures; however, both the PLLA plate and titanium miniplate may be at risk of fracture under poor reduction.

Influence of bone parameters on peri-implant bone strain distribution in the posterior mandible.

OBJECTIVES: The success rate of dental implants depends on the type of bone at the implant site. The purpose of the present study was to investigate the effects of the bone parameters at the implant-placement site on peri-implant bone strain distributions. STUDY DESIGN: The morphologies and bone densities of seventy-five potential implant sites in the posterior mandible were measured using computed tomography (CT). Based on the CT data, we defined bone parameters (low and high in terms of cancellous-bone density and crestal-cortical bone density, and thin and thick in terms of crestal-cortical bone thickness), and we constructed finite-element models simulating the various bone types. A buccolingual oblique load of 200 N was applied to the top of the abutment. The von Mises equivalent (EQV) strains in the crestal-cortical bone and in the cancellous bone around the implant were calculated. RESULTS: Cancellous-bone density greatly affected the maximum EQV strain regardless of the density and thickness of the crestal cortical-bone. The maximum EQV strains in the crestal cortical-bone and the cancellous bone in the low-density cancellous-bone models (of 150 Hounsfield units (HU)) were 1.56 to 2.62-fold and 3.49 to 5.31-fold higher than those in the high-density cancellous-bone models (of 850 HU), respectively. The crestal cortical-bone density affected the maximum EQV strains in the crestal cortical-bone and in the cancellous bone in the low-density cancellous-bone models. The crestal cortical-bone thickness affected the maximum EQV strains in the cancellous bone and in the crestal cortical-bone in the low-density cancellous-bone models. CONCLUSIONS: Our results confirm the importance of bone types for the peri-implant bone strain distribution. Cancellous-bone density may be a critical factor for peri-implant bone strain.

Theoretical efficacy of preventive measures for pathologic fracture after surgical removal of mandibular lesions based on a three-dimensional finite element analysis.

PURPOSE: Pathologic fracture of the mandible after removal of a lesion historically has been a clinical problem. The present study aimed to evaluate mandibular strength after removal of a lesion and to illustrate the theoretical efficacy of preventive measures against pathologic fracture based on a 3-dimensional finite element (FE) analysis. MATERIALS AND METHODS: A computed tomographic (CT)-based FE model of the mandible of a patient with a dentigerous cyst including a third molar was constructed. Using this model, the decrease of mandibular strength after virtual removal of the lesion was analyzed. The effect of the decrease of occlusal force and reinforcement by a miniplate was analyzed using a simple FE model of the mandible. Based on these analyses, removal of the cyst with the third molar was performed with a decrease of occlusal force and reinforcement by a miniplate. The validity of these procedures was analyzed using a CT-based FE model constructed after surgery. RESULTS: The von Mises stress in a CT-based FE model after virtual removal of the cyst with the third molar was markedly greater than that in the original FE model. In the analysis using a simple FE model, the stress around the fenestrated area was decreased after premolar loading compared with that after molar loading. In addition, miniplate placement around the fenestrated area markedly decreased the stress. Based on these results, the cast crowns of the first and second molars were removed and the fenestrated area of the mandible was reinforced with a 1.5-mm locking miniplate in the actual surgery. The von Mises stress in the fenestrated area was decreased and primarily borne by the miniplate in the analysis of a CT-based FE model constructed after surgery. CONCLUSION: The present study illustrated the theoretical efficacy of plate application for the decrease of stress on the mandible after surgical removal of a cyst including a third molar based on a simulation by FE analysis.

Maxillofacial fractures in children.

Maxillofacial fractures in Japanese children were retrospectively analyzed. The subjects were 287 patients aged 15 years and younger seeking treatment for maxillofacial fractures in the Department of Oral and Maxillofacial Surgery, Nara Medical University. The patients were 186 males and 101 females. Injuries most frequently occurred as a result of traffic accidents in 125 patients, 92 of which were bicycle-related accidents. Injuries by falling from one level to another were found in 49, primarily in younger children. One hundred seventy-nine fractures occurred in the mandible, 100 in the midface, and 8 in both. In the mandible, fractures most frequently occurred in condyle followed by symphysis. In the midface, alveolus was mostly involved. The facial injury severity scale ranged from 1 to 9 with an average of 1.83 and was higher in traffic accidents. Injury to other sites of the body was found in 33 patients, 28 of which occurred in traffic accidents. Observation was most frequently chosen in 84 patients. Intramaxillary fixation was chosen in 79, primarily for alveolar fractures and in younger children. Maxillomandibular fixation was chosen in 62 for mandibular fractures in older children. Open reduction and internal fixation was performed in 40, primarily in older children. The facial injury severity scale was higher in patients treated by open reduction and internal fixation and maxillomandibular fixation. Maxillofacial fractures in Japanese children showed characteristic features primarily depending on their age in terms of etiology, patterns, and treatment modalities.

Effect of clenching on biomechanical response of human mandible and temporomandibular joint to traumatic force analyzed by finite element method.

PURPOSE: The purpose of the present study was to analyze the effect of clenching on the biomechanical response of human mandible and temporomandibular joint (TMJ) to traumatic force by the finite element (FE) method. MATERIAL AND METHODS: FE models of the mandible and the TMJ in resting and clenching positions were prepared. Distribution and magnitude of von Mises stress were analyzed by applying force as a point load in the symphyseal, canine, body and angle regions of the mandible. In addition, strain energy density (SED) at the articular disc and in posterior connective tissue of TMJ was analyzed. RESULTS: In the resting position, von Mises stress was mainly concentrated at the condylar neck and in the retromolar region of the mandible. In the clenching position, the stress at the condylar neck decreased in all loadings. The stress in the retromolar region similary decreased in the symphyseal, canine and body loading, respectively; however, higher stress was observed in the retromolar region on the loading side in the angle loading. High SED was generated at the articular disc and in posterior connective tissues of TMJ in the resting position. The SED in these tissues decreased in all loadings in the clenching position. CONCLUSIONS: Clenching generally reduces stress at the condylar neck and in the retromolar region of the mandible, and strain energy at the articular disc and in posterior connective tissue of TMJ by traumatic forces on the mandible; however, clenching induces greater stress in the retromolar region on the loading side by traumatic force to the angle region.

Cepharanthine and Oral Lichen Planus Efficacy (COLE) study: protocol for a multicentre randomised controlled study assessing the efficacy and safety of cepharanthine with topical corticosteroids in oral lichen planus.

INTRODUCTION: Oral lichen planus (OLP) is a chronic, inflammatory oral condition leading to a range of symptoms from mild discomfort to severe pain, affecting patients' quality of life. Standard therapy involves the use of topical corticosteroids, although some patients respond insufficiently or develop resistance to therapy. We aim to explore if adding cepharanthine, an herbal extract from Stephania cepharantha Hayata, can enhance the efficacy of corticosteroid therapy in symptomatic OLP. METHODS AND ANALYSIS: This open-label, parallel-group, multi-centre, randomised controlled study will be conducted at three Japanese hospitals. It will compare safety and efficacy of integrated oral cepharanthine and corticosteroid therapy versus standard corticosteroid therapy. 50 symptomatic OLP patients will be randomised 1:1 to receive cepharanthine (30 mg/day) plus topical dexamethasone, or topical dexamethasone alone for 8 weeks. The primary outcome will be changed in pain intensity while drinking room-temperature water, measured on a visual analogue scale. The primary outcome is the change in pain intensity from baseline when drinking room-temperature water, evaluated using a visual analogue scale. Secondary outcomes are changes in the longest diameter of the target lesion from baseline to weeks 4 and 8, improvement and deterioration rates according to appearance and severity criteria at weeks 4 and 8, change in pain intensity when drinking room-temperature water from baseline to week 4, changes in pain intensity at rest from baseline to weeks 4 and 8, and the rates of adverse events. ETHICS AND DISSEMINATION: This protocol was approved by the Certified Review Board of Nara Medical University (CRB5200002). Participants will provide informed consent. Results will be disseminated in peer-reviewed journals and conferences. TRIAL REGISTRATION NUMBER: Japan Registry of Clinical Trials (jRCTs051220130).

Apoptosis induction through proteasome inhibitory activity of cucurbitacin D in human T-cell leukemia.

BACKGROUND: Human T-cell leukemia is an aggressive malignancy of T lymphocytes. T-cell leukemia has a very poor prognosis, even with intensive chemotherapy, indicating the need for development of new drugs to treat the disease. Triterpenoid cucurbitacins have been shown to have antitumor activity, but the mechanism of this activity is not fully understood. METHODS: The effects of cucurbitacin D on the proliferation and apoptotic induction of T-cell leukemia cells using the Cell viability assay and Annexin V staining were evaluated. To investigate the mechanisms of apoptosis, antiapoptotic protein, NF-κB, and the proteasome activity of leukemia cells treated with cucurbitacin D were evaluated by Western blotting both in vitro and in vivo. RESULTS: In this study, cucurbitacin D was found to inhibit proliferation and to induce apoptosis of T-cell leukemia cells. Constitutively activated NF-κB was inhibited by cucurbitacin D in the nucleus, which resulted in accumulation of NF-κB in the cytoplasm, leading to down-regulation of the expression of antiapoptotic proteins Bcl-xL and Bcl-2. Furthermore, cucurbitacin D induced the accumulation of inhibitor of NF-κB (IκB)α by inhibition of proteasome activity. Low doses of cucurbitacin D synergistically potentiated the antiproliferative effects of the histone deacetylase inhibitor VPA. Finally, the proapoptotic and proteasome inhibitory activities of cucurbitacin D also were demonstrated using SCID mice in an in vivo study. CONCLUSIONS: Cucurbitacin D induced apoptosis through suppression of proteasome activity both in vitro and in vivo, making cucurbitacin D a promising candidate for clinical applications in the treatment of T-cell leukemia.

The NF-kappaB RelA subunit confers resistance to Leishmania major by inducing nitric oxide synthase 2 and Fas expression but not Th1 differentiation.

Although the NF-kappaB transcription factors participate in both innate and adaptive immune responses, little is known about the role of the RelA subunit because mice lacking the rela gene die at embryonic day 14. To elucidate the role of RelA in Leishmania major infection, we prepared fetal liver chimeric mice by adoptively transferring embryonic day 13.5 rela(-/-) or rela(+/+) fetal liver into lethally irradiated host mice. About 90% of the peripheral lymphocytes of the chimeric mice had differentiated from rela fetal liver cells. The rela(-/-) fetal liver chimeric mice were highly sensitive to infection with L. major and died within 11 wk after infection. Despite the severity of the disease, parasite Ag-reactive Th1 cells developed normally. The rela(-/-) macrophages were less able to control intracellular parasite replication than rela(+/+) macrophages, despite showing equally efficient phagocytosis. Both in vitro NO production of macrophages and in vivo expression of NO synthase 2 in the lesions and draining lymph nodes was reduced in rela(-/-) fetal liver chimeric mice. Moreover, up-regulation of Fas in rela(-/-) macrophages was impaired both after in vitro stimulation with LPS and after in vivo infection with L. major, implying a defect in their ability to eliminate infected cells. Thus, RelA is necessary for macrophages to be resistant to intracellular parasite infection.

Maxillofacial fractures in older patients.

PURPOSE: The purpose of the present study was to analyze the trends and characteristic features of maxillofacial fractures in older patients. PATIENTS AND METHODS: The data from 247 patients aged 65 years old or older, who were treated for maxillofacial fractures at the Department of Oral and Maxillofacial Surgery, Nara Medical University, from October 1981 to March 2010, were retrospectively analyzed. RESULTS: Of the 247 patients, 127 were men and 120 were women; 50 patients had been treated in the first third of the period, 87 in the second, and 110 in the third. Injury had most frequently occurred because of falling on a level surface (n = 126), followed by a traffic accident (n = 84). Of the fractures, 140 were in the mandible, 90 in the midface, and 17 in both. In the mandible, the fracture lines were most frequently observed at the condyle, followed by the body, exclusively in edentulous patients. In the midface, the zygoma was mostly involved. The facial injury severity scale score ranged from 1 to 10 (average 1.81). Injury at other sites of the body was found in 45 patients. Observation was most frequently chosen (n = 127), primarily for those of older age, followed by open reduction and internal fixation in 46 and maxillomandibular fixation in 41 patients. The facial injury severity scale score was greatest in patients treated by open reduction and internal fixation, followed by those treated by maxillomandibular fixation. CONCLUSION: Maxillofacial fractures in older patients have been increasing and showed the characteristic features of etiology, patterns, and treatment modalities.

Biomechanical analysis of the strength of the mandible after marginal resection.

PURPOSE: This study investigated the biomechanical behavior of the mandible after marginal resection by tensile test in a human cadaveric mandible and finite element (FE) analysis. MATERIALS AND METHODS: Human cadaveric mandibular models after marginal resection were prepared with residual heights of 5, 10, and 15 mm. The strength in each of these mandibular models was examined by tensile testing. In addition, FE models of the mandible after marginal resection were prepared with residual heights of 5, 7.5, 10, 12.5, and 15 mm. Distribution and magnitude of von Mises stress were analyzed by applying bite forces of 151 N as a point load on the incisal region and 355.2 and 478.1 N on the premolar and molar regions on the nonresected and resected sides, respectively. At the molar region of the resected side, bite forces of 368.5 N and 286.9 N (80% and 60%, respectively, of 478.1 N) were also applied. RESULTS: On tensile testing, all cadaveric mandibular models were broken at the posterior resection corner. The tensile force was significantly larger in the model with a residual height of 15 mm compared with that of those with a 5- or 10-mm residual height. On FE analysis, von Mises stress was concentrated at the resection corner. The region of maximal von Mises stress concentration in FE models was consistent with that showing destruction on tensile testing. The relationship between the residual height and von Mises stress in the resection area was linear in models of the incisal, premolar, and molar loading on the nonresected side and quadratic in models of the premolar and molar loading on the resected side. The maximal von Mises stress in the resection area was highest during molar loading on the resected side under the present loading condition and exceeded the threshold for the development of pathologic fracture in the model with a residual height of around 10 mm or less. However, the maximal von Mises stress decreased in parallel with the reduction of bite force in the molar region of the resected side. CONCLUSIONS: The residual height and bite force are critical factors for the prevention of pathologic fracture of the mandible after marginal resection. Currently, a residual height of more than 10 mm and reduction of bite force are recommended to reduce the risk of fracture.

Maxillofacial fractures sustained in bicycle accidents.

PURPOSE: The purpose of this study was to analyze maxillofacial fractures sustained in bicycle accidents by demographics, cause of injury, site and severity of fractures, injuries to other sites of the body, and treatment modalities. PATIENTS AND METHODS: Data on 307 patients treated for maxillofacial fractures sustained in bicycle accidents in the Department of Oral and Maxillofacial Surgery, Nara Medical University from 1981 through 2009 were analyzed retrospectively. RESULTS: The patients were 166 males and 141 females (average age, 30.9 years). Causes of injury were a fall on a level surface in 169 patients, an automobile accident in 56, fall from 1 level to another in 28, and a motorcycle accident in 24. One hundred seventy-five fractures were observed in the mandible, 117 in the midface, and 15 in the mandible and midface. In the mandible, fracture lines were exclusively observed at the condyle. In the midface, the zygoma was most frequently involved. The Facial Injury Severity Scale ranged from 1 to 7 (average, 1.88). Injuries at other sites of the body were found in 47 patients and were frequently found in automobile and motorcycle accidents. Maxillomandibular fixation was most frequently chosen in 81 patients, followed by observation in 76 and open reduction and internal fixation in 71. The Facial Injury Severity Scale was highest in patients treated by open reduction and internal fixation, followed by those treated by maxillomandibular fixation. CONCLUSIONS: Maxillofacial fractures sustained in a bicycle accident frequently occurred by falling on a level surface and were not so serious in most cases; however, in accidents with motor vehicles, injuries to other sites of the body were observed at a higher rate.

A mandibular body fracture related to mouth-opening training in a dialysis patient.

A mandibular body fracture related to mouth-opening training in a dialysis patient is reported. A 61-year-old male patient had noticed pain in the right mandibular body and difficulty in mouth opening a week previously. The patient had been performing mouth-opening training for a couple of weeks. The right lower face was slightly swollen with tenderness at the right lower border of the mandible. Hypoesthesia of the right lower lip was also observed. A bone step was palpable on the alveolar ridge of the right mandible, but mobility was not marked. The mandible was atrophic in the body region with only four anterior teeth left. Panoramic X-ray examination revealed a moderately displaced fracture in the right molar region of the mandible. The patient had no severe pain or difficulty in eating using a partial denture. The patient had received dialysis for 17 years and had also been treated by warfarin and aspirin. The patient was followed up under restricted mouth opening. Osteosynthesis with bone remodeling was confirmed after 6 months by X-ray examination. No complication requiring further treatment occurred during the follow-up period. In this patient, a medically compromised condition under long-term dialysis is considered a predisposing factor, which made the atrophic mandible more susceptible to the stress related to mouth-opening training.

Serum vitamin D levels and survival of patients with colorectal cancer: post-hoc analysis of a prospective cohort study.

BACKGROUND: Recently, serum 25-hydroxyvitamin D (25OHD) levels were shown to be associated with the survival of patients with colorectal cancer. However, 25OHD levels were measured a median of 6 years before diagnosis or were predicted levels. In this study, we directly measured serum 25OHD levels at surgery and examined the association with survival among patients with colorectal cancer. METHODS: We started a prospective cohort study to find prognostic factors in patients with colorectal cancer from 2003 to 2008 and stored serum samples and clinical data. As part of a post-hoc analysis, serum 25OHD levels were measured by radioimmunoassay. Association between overall survival and serum 25OHD levels were computed using the Cox proportional hazard model adjusted for month of serum sampling as well as age at diagnosis, gender, cancer stage, residual tumor after surgery, time period of surgery, location of tumor, adjuvant chemotherapy and number of lymph nodes with metastasis at surgery. Unadjusted and adjusted hazard ratios (HR) and 95% confidence intervals (95% CI) were determined. RESULTS: Serum 25OHD levels were measured in 257 patients. Only 3% had sufficient levels (30 ng/ml and greater). Based on month of blood sampling, an annual oscillation of 25OHD levels was seen, with levels being lower in spring and higher in late summer. Higher 25OHD levels were associated with better overall survival under multi-variate analysis (HR, 0.91: 95% CI, 0.84 to 0.99, P = 0.027). CONCLUSIONS: These results suggest that higher 25OHD levels at surgery may be associated with a better survival rate of patients with colorectal cancer.

Thymocytes are activated by toluene inhalation through the transcription factors NF-κB, STAT5 and NF-AT.

Toluene has been extensively examined for effects on the central nervous system. To investigate the influence of low-level inhalation of toluene on the naive immune cells, male C3H/HeN mice were exposed to filtered air (control) and 50 ppm of toluene for 3 weeks. Low-level exposure resulted in (1) increased proliferation of thymocytes, (2) IL-2 production induced in thymocytes and (3) activation of the transcription factors NF-κB, STAT5 and NF-AT in thymocytes. These results suggest that thymocytes are sensitive cells and T cell activators are candidates for biomarkers for low-level exposure to toluene on naive immune cells.

Maxillofacial fractures resulting from falls.

PURPOSE: The purpose of this study was to analyze maxillofacial fractures resulting from falls in terms of the demographics, the circumstance of injury, the site and severity of fracture, and the treatment. PATIENTS AND METHODS: Data of 457 patients treated for fall-related maxillofacial fractures at the Department of Oral and Maxillofacial Surgery, Nara Medical University, Nara, Japan, from 1981 to 2007 were retrospectively analyzed. RESULTS: Patients were 163 males and 116 females with an average age of 51.3 years who had fallen on a level surface (simple fall), and 110 males and 68 females with an average age of 31.9 years in falls from a greater height (fall from height), respectively. Fractures of the mandible were more frequently observed than those of the midface. In the mandible, fracture lines were exclusively observed at the condyle, especially in simple falls. In the midface, the zygoma was most frequently involved. Facial Injury Severity Scale ranged from 1 to 6, with an average of 1.78 in simple falls, and from 1 to 9, with an average of 2.04 in falls from height, respectively. These were dependent on the causes and height of the fall. Fractures at the other sites of the body were found in 14 patients (5.0%) with simple falls and 38 (21.3%) with falls from height. Maxillomandibular fixation was most frequently chosen for mandibular fractures and observation for midface fractures. Open reduction and fixation was more frequently chosen in patients with falls from height than those with simple falls and in patients with a higher Facial Injury Severity Scale score. CONCLUSIONS: Maxillofacial fractures resulting from falls showed characteristic features in the demographics, the circumstance of injury, and the site and severity of fracture. Treatment was chosen according to these features.

Fate of developing tooth buds located in relation to mandibular fractures in three infancy cases.

The fate of developing tooth buds located in relation to mandibular fractures was investigated in three infancy cases. Three infants, 2 girls and a boy, aged from 1 year and 5-months old to 2 years and 6-months old, were treated for dislocated mandibular fracture in the symphyseal region by manual reduction and fixation with a thermoforming splint and circumferential wiring under general anesthesia. Fracture healing was uneventful in all cases. A few years later, no obvious deformity of the jaw or malocclusion was observed; however, malformation of the crown was found in one of the permanent teeth on the fracture line in the first case. In the second case, no abnormality was observed in one of the permanent teeth on the fracture line, but the effect on the other tooth could not be evaluated due to abnormality of the tooth probably not related to the injury. In the third case, root formation was arrested in one of the permanent teeth on the fracture line and the tooth was lost early after eruption. The development of tooth buds on the fracture line is not predictable and therefore, should be monitored by regular follow up.

Buccal Silicone Granuloma Caused by the Dental Infection.

The facial injection of liquid silicone is performed for cosmetic purposes. The use of injectable fillers in facial procedures has become extremely popular over the past decade. Most procedures are performed in the perioral, periocular, and cheek areas of middle-aged women. Even though silicone is biologically inert, its injection can result in the formation of granulomas. Silicone granulomas can result from an inflammatory or autoimmune tissue response. However, the development of silicone granulomas secondary to dental infection has not yet been reported. We report a case of a 73-year-old woman with a right buccal silicone granuloma that developed following a dental infection. Ultimately, this case healed completely after the surgical removal of all lesions. Silicone in the facial region may become infected by a dental infection, and infective silicone develops granulomas and cellulitis. In the context of cosmetic facial silicone injections, it is necessary to improve oral hygiene prior to dental treatment and to maintain a healthy oral environment after surgery. In some cases, surgical treatment using an intraoral approach is effective.