OBJECTIVES: To assess the association between muscle invasion by oral squamous cell carcinoma of the posterior mandibular alveolar ridge and cervical lymph node metastasis on the basis of preoperative magnetic resonance imaging (MRI). MATERIALS AND METHODS: Twenty-six patients with oral squamous cell carcinoma of the posterior mandibular alveolar ridge were evaluated by MRI. The associations between cervical lymph node metastasis and independent factors evaluated by MRI were analyzed. Overall survival was also analyzed in this manner. Representative biopsy specimens were stained with anti-podoplanin and anti-CD34 antibodies. RESULTS: Mylohyoid muscle invasion was associated with cervical lymph node metastasis. A combinational factor of mylohyoid and/or buccinator muscle invasion was also associated with cervical lymph node metastasis. Cervical lymph node metastasis and masticator space invasion had a negative effect on overall survival. No lymphatic vessels were identified near the tumor invasion front within the mandible. In contrast, lymphatic vessels were identified near the front of tumor invasion in the muscles. CONCLUSION: This study demonstrates an association between muscular invasion by oral squamous cell carcinoma of the posterior mandibular alveolar ridge and cervical lymph node metastasis.
Alveolar Process* ; Antibodies ; Biopsy ; Carcinoma, Squamous Cell* ; Epithelial Cells* ; Humans ; Lymph Nodes* ; Lymphatic Vessels ; Magnetic Resonance Imaging ; Mandible ; Muscles ; Neoplasm Metastasis*

No abstract available.
Surgery, Oral*

INTRODUCTION: The purpose of this study was to evaluate the clinical result of vertical alveolar distraction, especially the distracted alveolar bone and installed implants. MATERIALS AND METHODS: Twenty-one patients who have been received the vertical alveolar distraction and implant installation on 22 areas (3 maxilla and 19 mandible) using intraoral alveolar distraction device were examined. After consolidation period of 3-4 months, distraction devices were removed and 91 implants were installed in the distracted alveolar bone. The distracted bone and implants were evaluated clinically and radiographically. RESULTS: Mean height of distracted alveolar bone was 7.5+/-3.2 mm (range: 2.5-15.0 mm). Mean follow-up period after completion of the distraction was 3.1 years (range: 1.4-11.5 years). Mean resorption of distracted alveolar bone was 1.6+/-1.8 mm. The success and survival rates of implants was 95.3% and 100%, respectively. CONCLUSION: Results of this study indicate that vertical alveolar distraction procedure is a useful and stable method for alveolar ridge augmentation and implantation.
Alveolar Ridge Augmentation ; Dental Implants ; Follow-Up Studies ; Humans ; Maxilla ; Osteogenesis ; Osteogenesis, Distraction ; Survival Rate

PURPOSE: Calcium phosphate cement (CPC) is one of many useful materials for restoring tooth defects, periodontium and maxillofacial area. Chitosan is a biodegradable material that has been shown to promote the growth and differentiation of osteoblasts in culture. This study examined the interaction between odontoblasts and bio-calcium phosphate cement reinforced with chitosan. MATERIALS AND METHODS: 5x10(3) odontoblastic cells were seeded into each well. Various concentrations of bio-calcium phosphate cement reinforced with chitosan (10, 20, 50, 100, 200, 500 microg/ml, 1, 2, 4 mg/ml) were diluted and added to the wells. The well was incubated for 24 h, 48 h and 72 h. After incubation, the number of cells was assessed to determine the cell viability. A cytokinesis-block micronucleus assay and chromosomal aberration test were carried out to estimate the extent of chromosomal abnormalities. Microscopic photographs and RT-PCR were performed to examine the adhesion potential of bio-calcium phosphate cement reinforced with chitosan. RESULTS: Bio-CPC-reinforced chitosan did not show significant cytotoxicity. The number of damaged chromosomes in the cells treated with Bio-CPC-reinforced chitosan was similar to that in the control cells. There was no significant increase in the number of chromosomal aberrations in the Bio-CPC reinforced chitosan exposed cells. Microscopic photographs and RT-PCR confirmed the adhesive potential of bio-CPC reinforced chitosan to odontoblasts. CONCLUSION: Bio-CPC-reinforced chitosan did not affect the odontoblastic cell viability, and had no significant cytotoxic effect. Bio-CPC-reinforced chitosan showed adhesive potential to odontoblasts. These results are expected form the basis of future studies on the effectiveness of dental restorative materials in Bio-CPC reinforced with chitosan.
Adhesives ; Calcium ; Calcium Phosphates ; Cell Survival ; Chitosan ; Chromosome Aberrations ; Micronucleus Tests ; Odontoblasts ; Osteoblasts ; Periodontium ; Seeds ; Tooth

Thermally induced bone necrosis during implant surgery is a rare phenomenon and a potential contributing factor to implant failure. The frictional heat generated at the time of surgery causes a certain degree of necrosis of the surrounding differentiated and undifferentiated cells. The bone necrosis occurred in the mandible in all three cases, leading to a soft tissue lesion and pain. In each case, radiolucent areas appeared in the middle and apical portions of the implant 4 weeks after surgery. Thermally induced bone necrosis did not improve following systemic antibiotic medication, necessitating surgical treatment. The nonintegrated implants were removed, and meticulous debridement of dead bone and granulation tissue was performed. Then, new implants were implanted along with the placement of autogenous and xenogenic bone covered with a collagen membrane. No further complications occurred after re-operation. The radiolucencies around the new implants gradually resolved entirely, and the soft tissue lesions healed successfully. At 4-5 months after reoperation, implant loading was initiated and the implant-supported restorations have been functioning. The aim of this case report is to present the successful clinical treatment of three cases suspected to be caused by thermally induced bone necrosis after implant drilling.
Collagen ; Debridement ; Dental Implants ; Friction ; Granulation Tissue ; Hot Temperature ; Mandible ; Mandrillus ; Membranes ; Necrosis ; Osteonecrosis ; Reoperation

Midline craniofacial dermoids are rare lesions resulting from the abnormal fusion of embryologic structures. The clinical features of craniofacial dermoid cysts show a range of presentations, including infection, asymptomatic puncti, or seizure secondary to intracranial invasion. Appropriate management involves an accurate diagnosis of the dermoid cyst and a complete resection.
Asymptomatic Infections ; Dermoid Cyst ; Seizures

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

INTRODUCTION: Osteoporosis is a major health problem in the elderly that involves changes in the properties of bone as well as impaired bone healing around a titanium implant in both humans and animals. This study examined effect of low intensity pulsed ultrasound (LIPUS) on the bone healing process around a titanium implant in osteoporosis-induced rats. MATERIALS AND METHODS: Sixteen rats were divided into two groups. A control group with osteoporosis induced by removing both ovaries and an experimental group of rats that were applied with LIPUS after osteoporosis had been induced. A screw type titanium implant (diameter, 2.0 mm: length, 3.5 mm, Cowell-Medi, KOREA) was placed into the tibias of 16 rats. The control and experimental group contained 8 rats each. The rats were sacrificed at 1, 2, 4, and 8 weeks after implantation to examine the histopathology and immunochemistry. RESULTS: The histopathology examination revealed earlier new bone formation in the experimental group than the control group. In particular, at 1 week after implantation, more new bone matrix and collagen were observed around the implant of the experimental group compared to the control group. Immunochemistry analysis showed that the level of OPG expression of the experimental group was higher in the early stages than in the control group. After 8 weeks, the levels of OPG expression were similar in both groups. The expression level of receptor activator of nuclear factor kB ligand (RANKL) was stronger in the experimental group than the control group. After 4 weeks, the level of RANKL expression was similar in both groups. CONCLUSION: These results suggest that the application of LIPUS to implantation can promote bone healing around titanium in osteoporosis animals.
Aged ; Animals ; Bone Matrix ; Collagen ; Dental Implants ; Female ; Humans ; Immunochemistry ; Osteogenesis ; Osteoporosis ; Ovary ; Rats ; Tibia ; Titanium

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

INTRODUCTION: This study examined the effect of autogenous tooth bone used as a graft material for bone regeneration in an artificial bony defect of minipigs. MATERIALS AND METHODS: Four healthy minipigs, weighing approximately 35-40 kg, were used. Four standardized artificial two-walled bony defects, 5 mm in length and depth, were made on the bilateral partial edentulous alveolar ridge on the mandible of minipigs, and autogenous tooth bone was augmented in the right side as the experimental group. On the other hand, only alloplastic bone graft material HA was grafted with the same size and manner in the left side as the control group. All minipigs were sacrificed at 4 weeks after a bone graft and evaluated histologically by Haematoxylin-eosin staining. The specimens were also evaluated semi-quantitatively via a histomorphometric study. The percentage of new bone over the total area was evaluated using digital software for an area calculation. RESULTS: All specimens were available but one in the left side (control group) and two in the right side (experimental group) were missing during specimen preparation. The amount of bone formation and remodeling were higher in all experimental groups than the control. The mean percentage area for new bone in the experimental and control groups was 43.74+/-11.96% and 30.79+/-2.93%, respectively. CONCLUSION: Autogenous tooth bone is a good alternative to autogenous bone with the possible clinical feasibility of an autogenous tooth bone graft in the reconstruction of bony defects.
Alveolar Process ; Bone Regeneration ; Hand ; Mandible ; Osteogenesis ; Regeneration ; Swine, Miniature ; Tooth ; Transplants