No abstract available.
Humans

No abstract available.

This is to report a case of immediate reconstruction after hemimandibulectomy by using of bicorticocancellous block bone harvested from the iliac crest in the case of an ameloblastomaon the mandible. Because the lesion involved condylar area, it was reconstructed with titanium artificial condyle attached to A/O metal plate. Three weeks after the operation, infection developed with suppuration and was well treated with adequate antibiotic therapy and drainage. The patient has been followed up over a four-year period and taken an orthopantomogram every three or six month for the examination of mandibular movement, the potentiality of recurrence and the remodeling of the grafted bone. At present, the patient is satisfied with her appearence and has a normal occlusion with proper masticatory function, and there is no sign of recurrence.
Ameloblastoma* ; Drainage ; Humans ; Mandible ; Mandibular Osteotomy ; Recurrence ; Suppuration ; Titanium ; Transplants*

The objective of this study was to find out whether the unilateral distraction of mandible has an influence on temporomandibular joint and if it does, how significant the influence is. Four beagle dogs were used in this study. Each dog had two implants placed into the left mandible. The mandible was distracted for 14days with an distraction device as an amount of 0.75mm, twice per day after osteotomy between two implants. Each animals were sacrificed at the second, fourth, sixth and eighth week after the total distraction amount of 10.5mm were gotten. Upon embedding and staining, the specimens were evaluated with a light microscope. The results were as follows. 1. For the second week group, the articular cartilage and osteoid seam of temporal bone and condyle were relatively well maintained. There were not any significant differences between distraction side and non distraction side. 2. For the fourth week group, the periosteal reaction was activated and the articular cartilage and osteoid seam of temporal bone and condyle were severely thickened-especially at posterior portion of distraction side. This findings revealed that the unilateral distraction forces has more influence on distraction side than on non distraction side, and on posterior portion than on anterior portion. 3. For the sixth and eighth week group, the thickness of meniscus in distraction side gradually recovered to the initial level. The thickened articular cartilage and osteoid seam of temporal bone and condyle were decreased in distraction side and showed relatively stable in non distraction side. From this results, we suggest that several considerations are required such as using an occlusal splint, maintaining the stability of bone distraction device and evaluating bone distraction rate to minimize the damages of temporomandibular joint tissues in early stage of distraction side.
Animals ; Cartilage, Articular ; Dogs ; Mandible* ; Occlusal Splints ; Osteotomy ; Temporal Bone ; Temporomandibular Joint*

In this study, the rate of bone formation and the pattern of bone to implant contact surface around HA coated implant and pure Ti implant inserted into the irradiated tibia of rabbit were compared. Sixteen mongrel mature male rabbits were used as experimental animal. Each rabbit received 15 Gy of irradiation. Four weeks after irradiation, two holes were prepared on the tibia of each rabbit for placement of HA coated type and pure Ti type implants. Prior to implant placement, one group received steroid irrigation and the control group was similarly irrigated with normal saline. This was immediately followed by placement of the two different types of implants. Postoperatively, tetracycline was injected intramuscularly for 3 days. For fluorescent labelling, 3 days of intramuscular alizarine red injection was given. 2 weeks before sacrifice, followed by intramuscular calcein green on the last 3 days before specimen collection. Each rabbit was sacrificed on the second, fourth, sixth and eighth week after the implantation. The specimens were observed by the light microscope and the fluorescent microscope. The results were as follows; 1. All implants inserted into the irradiated tibia of rabbit were free from clinical mobility and no signs of bony resorption were noted around the site of implant placement. 2. Under the light microscope, new bone formation proceeded faster around implants that received steroid irrigation compared to the control group irrigated with saline. Bone to implant contact surface was greater in the steroid irrigated group than the saline irrigated group. Therefore, better initial stabilization was observed in the group pretreated with steroid irrigation. 3. Under the light microscope. HA coated implants showed broader bone to implant contact surface than pure Ti implants, and HA coated implants had better bone healing pattern than pure Ti implants. 4. In the steroid pretreated group, acceleration of bone formation was demonstrated by fluorescent microscopy around the 2, 4 weeks group and the 6 weeks HA coated implant group. The difference in the rate of bone formation proved to be statistically significant (P<0.05). Faster bone formation was noted in the saline irrigated group in the 6 weeks pure Ti implants and 8 weeks group. The difference was not statistically significant(P<0.05). 5. For the rabbits that were sacrificed on the second and fourth week after the implant placements, the rates of bone formation around HA coated implants proceeded faster than those around pure Ti implants under the fluorescent microscopy. For the rabbits that were sacrificed on the sixth week after the implant placements, the rates of bone formation around pure Ti implants proceeded faster than those around HA coated implants under the fluorescent microscopy. But this result did not show statistical significance (P<0.05) For the rabbits that were sacrificed on the eighth week after the implant placements, the rates of bone formation around HA coated implants proceeded faster than those around pure Ti implants under the fluorescent microscopy. This result was statistically significant (P<0.05).
Acceleration ; Animals ; Humans ; Male ; Microscopy ; Osteogenesis* ; Rabbits ; Specimen Handling ; Tetracycline ; Tibia*

The condyle head of mandible was usually influenced by the stressful forces generated from a voluntary movement of bone fragment after the sagittal ramus osteotomy which would be mainly performed for the mandibular deformity patient. In this study we measured the stress values exerted on condyle and evaluated which area of condyle had a more stress concentration while condyle head moved in X, Y and Z axis by using a 3 dimensional finite element model. The result were as follows: 1. On bodily movement, the value of maximum force was 40.98Kg/cm2 at the (-X) direction and the stress area was the center of superiposterior nonaticular area of the condyle. 2. On ratational movement, the value of maximum force was 173.1Kg/cm2 at the (+Y) direction and the stress area was the anterior area of condyle neck. 3. From the general point of view there were more stress on rotational movement than on bodily movement. 4. The stress concentration area was the condyle head on bodily movement and the condyle neck on ratational movement. 5. From the result of this study. We found out that this results were a correspondence with clinical predictions in which a condyle head got the most stress concentration only when a condyle head in the posterior rotational position during orthognathic surgery. 6. The results of this study show that we should consider not to place the condyle head in the posterior position and posterior rotational position during orthognathic surgery.
Axis, Cervical Vertebra ; Congenital Abnormalities ; Head ; Humans ; Mandible ; Mandibular Condyle* ; Neck ; Orthognathic Surgery ; Osteotomy

Anterior open bite is a condition in which maxillary and mandibular incisors do not occlude at central occlusion. It is a vertical discrepancy of the jaws and dental arches that has many etiologic factors making it difficult in diagnosis, treatment and prediction of prognosis. One of the causes of open bite is abnormal size and shape of the tongue. Macroglossia, a condition in which tongue is oversized, is caused by several factors which are not clearly identifiable, and it may be a major factor of anterior and posterior open bite. Macroglossia is subdivided into true, functional and pseudomacroglossia depending on its relative size in the oral cavity. In this case report, a patient was diagnosed as skeletal Class II with pseudomacroglossia, and was treated with SARPE in order to expand the narrowed maxillary arch and quad helix for the mandibular arch. As a result the transverse deficiency was treated. In the adult patients where no skeletal growth is expected, SARPE has shown to be effective in treating maxillomandibular transverse discrepancies in which macroglossia was accompanied as in this case.
Adenine ; Adult ; Carbamates ; Dental Arch ; Deoxycytidine ; Drug Combinations ; Humans ; Incisor ; Jaw ; Macroglossia ; Mouth ; Open Bite ; Organophosphonates ; Palatal Expansion Technique ; Prognosis ; Quinolones ; Thiazoles ; Tongue ; Elvitegravir, Cobicistat, Emtricitabine, Tenofovir Disoproxil Fumarate Drug Combination

Skeletal anterior open bite is a difficult problem to correct in orthodontic treatment. To treat adult patients who have skeletal anterior open bite, we considered two methods. Combination treatment of orthodontics & surgery and camouflage orthodontic treatment. In adults, treatment of severe skeletal anterior open bite consists mainly of surgically repositioning the maxilla or the mandible. However, camouflage therapy is often the treatment of choice for skeletal open bite patients who have mild to moderate skeletal discrepancies when growth modification is no longer possible. But excellent results generally require careful coordination of the orthodontic and surgical phases of treatment. This is a case report of a skeletal anterior open bite patients who were treated with orthodontic treatment and orthognathic surgery. First case was diagnosed as skeletal class I malocclusion & bimaxillary protrusion with anterior open bite, and finally treatment ended for removal of open bite with orthodontic procedure and bimaxillary anterior segmental osteotomy surgery. Second case was diagnosed as skeletal class II malocclusion with open bite & mandibular retrusion, and was treated with only camouflage orthodontics because she feared to have a surgery. In a regular follow up visit after debonding we proposed to the patient advanced genioplasty, and in her agreement her facial esthetics was improved through the surgery.
Adult ; Esthetics ; Follow-Up Studies ; Genioplasty ; Humans ; Malocclusion ; Mandible ; Maxilla ; Open Bite ; Orthodontics ; Orthognathic Surgery ; Osteotomy ; Retrognathia

There are three designs of thread form in screw type implants: V-thread, Reverse buttress thread and Square thread. The purpose of this study was to find out how thread form designs have an influence on the equivalent stress, equivalent strain, maximum shear stress and maximum shear strain and which design of thread form generates more maximum equivalent stress and strain. 3-D finite element analysis was used to evaluate the stress and strain patterns of three tread types. The results of this study were as follow. 1. Under the 200N of axial load, the value of maximum equivalent stress is smallest in square thread and there is no significant difference between that of V thread and reverse buttress thread. 2. Under the 200N of axial load, the value of maximum equivalent strain is largest in V thread and smallest in square thread. 3. Under the 200N of axial load, the value of maximum shear stress is smallest in square thread and there is no significant difference between that of V thread and reverse buttress thread. 4. Under the 200N of axial load, the value of maximum equivalent strain is largest in V thread and there is no significant difference between that of square thread and reverse buttress thread. 5. Above results show that the square thread has special advantages in stress and strain compared with other thread types, especially in shear stess which is most determinant to implant-bone interface. Considering the superior biomechanical properties of square form implant, we presume that square form implant has better clinical results than the other types of implants in the same clinical conditions.
Finite Element Analysis*

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.
Adult ; Animals ; Biology ; Bone Lengthening ; Bone Transplantation ; Cartilage ; Dental Occlusion ; Dogs* ; Extremities ; Humans ; Islands ; Male ; Mandible* ; Orthopedics ; Osteocalcin ; Osteogenesis ; Osteonectin ; Osteotomy ; Paraffin ; Periosteum ; Regeneration ; Surgical Instruments ; Tissue Donors ; Transplants