ABSTRACT
A squamous odontogenic tumor (SOT) is an epithelial originated benign tumor. It has been rarely reported and most was intramural type. We observed a case of SOT in the mandible. It was associated with the odontogenic cyst. It was shown positive to pancytokeratin and p53. Considering that the case was free from recurrence for 5 years after surgery, p53 positive did not seem to be related to the prognosis of the disease.
Subject(s)
Mandible , Odontogenic Cysts , Odontogenic Tumor, Squamous , Prognosis , RecurrenceABSTRACT
A squamous odontogenic tumor (SOT) is rare disease and it is believed to originate from epithelial rests of Malassez of the periodontal membrane. Neither sex nor site predilection in either jaw has been established. Some lesion can be shown in juxtaposition in tooth roots. Although most lesions remain smaller than 2 cm, our cases involved a half of left mandibular ramus. The exact pathogenesis is still unknown. We report a case of SOT including the results of immunohistochemical study of pancytokeratin and p53.
Subject(s)
Jaw , Mandible , Membranes , Odontogenic Cysts , Odontogenic Tumor, Squamous , Rare Diseases , Tooth RootABSTRACT
40-years old) was 1.80+/-0.52mm and 1.51+/-0.58mm in younger age(<40-years old). The period between L2-and L3 showed significant changes in marginal bone oss(p<0.05). In conclusion, the marginal bone loss in L2-L3 period was most severe. Thus, the intensive care and follow-up in this period will be required to prevent excessive bone loss.
Subject(s)
Female , Humans , Male , Follow-Up Studies , Heart , Critical Care , TransplantsABSTRACT
The neurofibroma in oral cavity is typically associated with neurofibromatosis. The solitary neurofibroma is commonly observed in skin. It is relatively rare in oral cavity and usually observed in the tongue, buccal mucosa, and vestibule. The rare types of solitary neurofibromas have been reported as a case report and they were in the inferior alveolar nerve, infratemporal fossa, maxilla, and palatal ginviva. In our hospital, the presented case was the first case as reported as solitary neurofibroma in the oral cavity. The prognosis after excision and the review of literatures were presented.
Subject(s)
Mandibular Nerve , Maxilla , Mouth , Mouth Mucosa , Neurofibroma , Neurofibromatoses , Prognosis , Skin , TongueABSTRACT
Subject(s)
Adenoma, Pleomorphic , Parotid Gland , Retrospective Studies , Salivary Ducts , Salivary Glands , Salivary Glands, MinorABSTRACT
In the field of oromaxillofacial surgery, it is not common to meet arteriovenous malformation(AVM) patients. AVMs are the result of congenital abnormality, or the result of trauma of adjacent vessels. This patients need special care in surgical procedure. Also, they need management include clinical, radiographic, and angiographic assessment. We report a case of the AVM in right maxillary artery, who embolized PVA and obtained good result.
Subject(s)
Humans , Angiography , Arteriovenous Malformations , Congenital Abnormalities , Maxillary ArteryABSTRACT
Using the rat's skull, the study on the biodegradability and guided bone regeneration of the chitosan membrane was performed. The results are as follows: 1. The biodegradability of the chitosan membrane could not be confirmed, but after 12 weeks, this membrane did not yet break into small pieces and there was no specific local tissue reaction. 2. It was not certain whether the pore size of this membrane was affected on osteoblastic activity. 3. After 6 weeks, the bony defect area of rat's skull was not completely filled, but on high magnification it showed that the osteoclasts and the osteoblasts were observed in the regenerating area. In conclusion, the chitosan membrane developed in this study was fit for guided bone regeneration.
Subject(s)
Bone Regeneration , Chitosan , Membranes , Osteoblasts , Osteoclasts , SkullABSTRACT
As the result of the study concerning "bone inducibility of chitosan", 1. "BMP-2"was observed mainly through the test when the "osteoblast"is exposed to the "chitosan". The expression of BMP-2 was 542.63 times compared to control after 2 hours exposure and it was maintained 16.60 times till 24 hours. 2. The expression of BMP-4 was decreased compared to control during exposure. 3. The expression of BMP-7 revealed two peaks during exposure. 4. The expression of osteocalcin was increased in early phase, and then decreased. Although it is not clear whether the "chitosan"is clinically effective material as a "bone induction material", we could say that it has a function for bone induction. Further detailed study will be required.
Subject(s)
Humans , Bone Morphogenetic Protein 7 , Chitosan , Osteoblasts , OsteocalcinABSTRACT
The lateral rhinotomy signifies only an incision and not on operation and a lateral rhinotomy incision with osteotomy of the nasal bones provides access to the entire nasal cavity and maxillary, ethmoid, and sphenoid sinuses as well as the frontal sinus if the floor is removed, permitting removal of benign lesions at these sites and en bloc resection of the ethmoid labyrinth and the party wall between the nasal cavity and antrum with infiltrating tumors. The authors treated a tumor patient and a midfacial bone fracture patient via lateral rhinotomy approach and had a good result. So we report the cases with literature review.
Subject(s)
Humans , Ear, Inner , Fractures, Bone , Frontal Sinus , Nasal Bone , Nasal Cavity , Osteotomy , Sphenoid SinusABSTRACT
With the object of providing a temporary artificial periodonal ligament-like membrane around the dental implant, 10 Branemark type implants were coated with commercially available chitosan(Fluka Co., Buchs, Switzerland) which has a molecular weight of 70,000 and 80% deacetylation degree. Once this bioactive hydrophillic polymer(chitosan) contacts with blood or wound fluids, it becomes swollen and penetrates into the adjacent cancellous bone. Thus the interface between implant and surrounding bone is completely filled with chitosan. This tight junction in early healing phase enhances primary stability. The chitosan coated dental implants were implanted into the fresh patella bones from porcine knees, since the thickness of cortical bone is relatively even and their cancellous structure is homogenous. To test the shock absorbing effect, 1mm delta-rogette strain gage was installed behind the implant. The results showed 1. the principal strain peak value directed to the impact of coated implant was 0.064 0.018(p<0.05) and that of uncoated implant was 0.095(0.032 p<0.05). 2. the peak time delay of coated implant was 0.056sec(0.011 p<0.05) and that of uncoated implant was 0.024sec(0.009 p<0.05). It can be reasoned from this results that the chitosan coating has a shock absorbing effect comparable with a temporary artificial periodontal ligament.
Subject(s)
Absorption , Chitosan , Dental Implants , Knee , Membranes , Molecular Weight , Patella , Periodontal Ligament , Shock , Tight Junctions , Wounds and InjuriesABSTRACT
The purpose of this experiment was to examine the histological changes and the pattern of expression of proliferating cell nuclear antigen(PCNA) and type I collagen in the elongated bone affected by osteodistraction of the mandibular body in an adult canine model. Seven adult male mongrel dogs weighing over 20kg were used for this experiment. The author excluded 3 animals because they died before the planned time of sacrifice. The custom-made linear extraoral device and 4 bicortical fixation screws 2.3mm in diameter, 50mm in total length, 15mm in screw length were used in each animal. The distal part of the distractor produced a 0.75mm gap between proximal and distal bony segments every 360 degrees.turn of the rotation rod of the device. The mandibular body of the right side from each animal was experimental side and the left side was left intact and served as control. At the experimental side, the mandibular body was osteotomized. After 5-day latency period, the segments were distracted with a rate of 1.1mm/day and a rhythm of two/day for ensuing 7 days. The animals were sacrificed at the 4th. 17th, and 32th day after the end of the distraction. The bony specimens were decalcified, embedded in paraffin, sectioned 5micrometerthick and stained with Masson trichrome and examined under the light microscope. The immunohistochemical examinations using anti-PCNA antibody and anti-type-I collagen antibody were performed to examine the pattern of the expression of PCNA and type I collagen, respectively, . RESULTS: 1. The mean increment of the distance between the proximal and distal screw-holding parts of the distractor was 6.8mm. The average elongation of the mandible in the expermental side was 5.3mm. The loss of elongation was 1.5mm in average. 2. New bone was already observed at the 4th. day after the end of distraction. But, bony union was not completed in the distraction gap at the 32th. day after the end of distraction by radiographic and microscopic examinations. 3. The expression rate of PCNA positive cells in the distraction gap had a tendency of decrease from 35.1-68.8% initially, to 49.1%, and finally to 17.6-27.2%. But at the final period, the tissue of the elongated gap still had the ability of cell proliferation. On the other hand, the expression of PCNA positive cells in the control side were negligible through the experimental period. 4. PCNA positive cells were observed primarily both at the central fibrous zone and at the region of just adjacent to CFZ which initiated new bone formation. 5. The expression pattern of the type I collagen was not zone-specific. They were observed diffusely throughout the elongation gap. 6. The predominant mechanism of new bone formation in the distraction gap was intramembranous. But, some of the regenerated bone was formed by endochondral ossification.
Subject(s)
Adult , Animals , Dogs , Humans , Male , Cell Proliferation , Collagen , Collagen Type I , Hand , Latency Period, Psychological , Mandible , Osteogenesis , Paraffin , Proliferating Cell Nuclear AntigenABSTRACT
PURPOSE: Traditionally, the treatement of choice has been a bone grafting procedure to increase the length of bone in case of actual length discrepancy. But, bone grafting procedure has many disadvantages, for example, graft resorption, donor site morbidity, and so on. So, many trials have been performed to avert the use of autogenous bone graft via introducing new materials or methods. And, one of those trials has been realized by the development of a technique inducing bone lengthening by osteotomy (or corticotomy) and slow gradual distraction of the osteotomized segments. This new technique of bone lengthening dates back to the early 20th century. But, the majority of information concerning the biology of new bone formation during bone lengthening and technical details of the procedure were produced by extensive clinical and experimental studies performed by Ilizarov, a Russian surgeon. According to Ilizarov, with adequate blood supply, preservation of periosteum, rigid fixation of the osteotomized segments, and proper rate and rhythm of distraction, intramembranous bone rapidly develops within the distraction gap in the limb lengthening procedure. In the limb lengthening, many orthopedic surgeons try to observe the biologic and clinical principles recommended by Ilizarov. In the oral and maxillofacial region, however, not a few studies must be performed to apply this surgical technique in the clinical cases. Besides, the mechanism of bone formation in the distraction gap is not clear, yet. The purpose of this experiment was to scrutinize seriallly the histological changes in the elongated bone affected by osteodistraction of the mandibular body in an adult canine model. In addition, it was performed to confirm the presence of specific region(s) which was important in the bone formation in the gap through the observation of the expression pattern of osteocalcin and osteonectin with the immunohistochemical examination. MATERIALS AND METHODS: The experimental and control specimens were obtained from seven adult male mongrel dogs weighing over 20kg. The distractors were custom-made linear extraoral devices and bicortical fixation screws were 2.3mm in diameter, 50mm in total length, 15mm in screw length. The distractors were devised to produce a linear gap of 0.75mm between two bony segments every 360.turn of the rotation rod of the device. The mandibular body of the right side of each animal was corticotomized perpendicular to the occlusal plane and then two bony segments were separated completely by careful manipulation of the segments with bone forceps. The left side of each animal was left intact. This side was served as control. At sixth day after osteotomy and fixation of the segments were performed, distraction of the segments was commenced with a rate of 1.1mm/day and a rhythm of two/day for ensuing 7 days. the animals were euthanized at the 16th. 29th, and 44th day after the osteotomy. The bony specimens were decalcified, embedded in paraffin, sectioned 5micrometerthick and stained with H&E. The prepared specimens were examined under the light microscope. And, immunohistochemical examinations using anti-osteocalcin antibody (OC1, Biodesign, USA) and anti-osteonectin antibody Haematologic Technologies Inc., Essex, VT) to locate the expressions of osteocalcin and osteonectin, respectively, were performed. RESULTS: 1. New bone was observed already at the 16th. day after osteotomy. This suggests that new bone formation in osteodistraction was commenced at an early stage of the regenerative process. But, radiologically and microscopically, bony union was not completed in the distraction gap at the 44th. day after osteotomy. Therefore, rigid fixation must be maintained between the bony fragments till the complete bony union is confirmed clinically rather than one month or so after the completion of distraction. 2. Intramembranous bone formation predominated the regenerative process in the distraction gap. Some of the regenerated bone, however, was formed by endochondral ossification. 3. Focal islands of cartilage were observed at all experimental periods. 4. Considering the expression pattern of osteocalcin and osteonectin, new bone formation was considered to be commenced at the region adjacent to the central fibrous zone and therefore this region, especially the periosteum of this region, was important in regeneration of the distraction gap. Focus needs be set on the region adjacent to the CFZ and the role of periosteum in performing further experiments to elucidate the mechanism of bone formation in the distraction gap.
Subject(s)
Adult , Animals , Dogs , Humans , Male , Biology , Bone Lengthening , Bone Transplantation , Cartilage , Dental Occlusion , Extremities , Islands , Mandible , Orthopedics , Osteocalcin , Osteogenesis , Osteonectin , Osteotomy , Paraffin , Periosteum , Regeneration , Surgical Instruments , Tissue Donors , TransplantsABSTRACT
The purpose of present study is comparing the effect of Teflon Membrane and Nylon Membrane on bone regeneration in rabbit tibia. The 6 defects of 8x8x5mm size were drilled with dental handpiece in rabbit tibia, which on left side as an order of Control group(no coverage), Group 1(Nylon 5 micrometer size), Group 3(Nylon 10 micrometer size), and on right side Control group, Group 2(5 micrometer Teflon), Group 4(10 micrometer Teflon). Animals were killed at 7, 10, 14, 42 days to make specimens and observed the difference of healing potentials with light microscopy. The results were as follows ; 1. New bone formation has taken place at 14 days in Guided Bone Regeneration (GBR) group comparing to the Control group of massive inflammatory status. 2. Larger pore membrane allows more favorable healing potentials. Bone formation started earlier in larger membrane pore groups than smaller groups, until 14 days. 3. Bone forming potentials of Teflon membrane group was higher than Nylon membrane groups, Control group has the lowest bone forming potentials. 4. New bone formation was almost ended in 42 days, and there was no difference of bone formation between Nylon and Teflon membrane group of different size. There was no difference of bone formation at final stage(42 days) between Nylon membrane and Teflon membrane of same pore size. So nylon membrane may be clinically usable in guided bone regeneration case with further studies.
Subject(s)
Animals , Bone Regeneration , Control Groups , Membranes , Microscopy , Nylons , Osteogenesis , Polytetrafluoroethylene , TibiaABSTRACT
Condylar process of mandible is an important and fuctionally versatile part of the mandible. There were quite large amount of investigations on the functional and anatomical adaptation of the temporomandibular joint(TMJ) to the surrounding tissues. But controversies on the mechanism of functional adaptation of the joint still exist. In this research, we investigated changes in the TMJ by the lateral deviation of the maxillary incisor to shift the mandible right, and bone the undecalcified microscopic sections with fluorescent microscope and von Kossa staining with bright field microscope. Results were as follows: 1. Lateral deviation rendered shifting and tilting of the mandible, There were, compressions in the right joint and opening of the left joint space at early stage. At the same time, both condyles shifted slightly to anterior. 2. After 2~4 weeks, left condyle showed anterior displacement and compressions in the joint space. Right condyle showed only slight shift to the anterior. 3. Regardless of the direction of the lateral shift, anterior bite plate compressed both condyle heads until 2 weeks. 4. There are bone resorptions in the anterior aspect of the condyle head and apposition of posterior border. Bone remodeling were observed between 3 and 4 weeks. 5. After 8 weeks of the experiment, there were little differences in condylar morphology between experimental and control group, though slight shifting and compression were still present in the experimental group. Lateral deviation of mandible evoked active remodeling of the TMJ until functional and anatomical reconstruction of TMJ position was achieved.
Subject(s)
Bone Remodeling , Bone Resorption , Head , Incisor , Joints , Mandible , Temporomandibular JointABSTRACT
Modern antibiotic therapy and rapid surgical intervention have greately reduced the complication from the spread of odontogenic infections. Nevertheless, fatalities from dental infections continue to occur. One of the most threaded, and probably lethal form is the mediastinal abscess. This is a case of Ludwig's angina dissected along deep cervical planes into the mediastinum caused a virulent mediastinitis and abscess, computed tomography precisely delineated the extent of the infection. Incomplete debridement resulted in a residual abscess and persistent systemic sepsis that culminated in the patient's death. Aggressive antibiotic treatment of the orofacial cellulitis along with complete mediastinal drainage are recommended for optimal outcome.
Subject(s)
Abscess , Cellulitis , Debridement , Drainage , Ludwig's Angina , Mediastinitis , Mediastinum , SepsisABSTRACT
The results of implant therapy for the functional rehabilitation of tumor-patients are presented and discussed. It can be shown, that mandibular implants without osteoplasty show a similar low failure rate of about five percent as implants used in a control group of edentulous patients. Implants used in conjunction with osteoplasty and maxillary implants show a less favourable prognosis. Because of special problems and possible complications, especially in irradiated patients, we suggest a restrictive indication for implantations and a close follow-up of the patients.