• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제33권4호
• /
• pp.293-300
• /
• 2011

Purpose: Substance P is a well known neurotransmitter and has been known to mediate pain. Recently, it has been unveiled that substance P is involved in the recruitment of mesenchymal stem cells to wound sites. The purpose of this study was to exam bone formation when a combination of substance P and silk fibroin was used in a bone defect model. Methods: Twenty rabbits were used and 40 calvarial defects were formed. They were divided as 4 groups (unfilled control, silk only, silk+$10{\mu}g$/ml substance P; Sub10, and silk+$100{\mu}g$/ml substance P; Sub100). All animals were humanely sacrificed 4 or 8 weeks after grafting. The specimens were analyzed by micro-computerized tomography and histological analysis. Results: When compared to the unfilled control to silk only group, there was significant difference in bone mineral density (BMD) and the attenuation coefficient (AC) at 4 weeks ($p$=0.037 and 0.038, respectively). When compared Sub10 group to Sub100 group, there was significant difference in BMD and AC at 8 weeks ($p$=0.004 for all). Residual graft amounts were $52.1{\pm}15.8$%, $15.2{\pm}9.2$% and $9.0{\pm}3.3$% for silk only, Sub10, and Sub100 groups, respectively. When comparing the residual graft amount of silk only to sub10 or sub100, the differences were statistically significant ($p$ <0.001). Conclusion: The silk fibroin scaffold showed higher BMD and AC than the unfilled control. The combination graft with substance P and silk fibroin scaffold showed a faster graft degradation than with a silk fibroin scaffold only.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제34권4호
• /
• pp.233-238
• /
• 2012

Purpose: To evaluate the effect of silvernanopartilce treated implants on the bone formation and osseointegration. Methods: Silvernanoparticle was produced using an anodic oxidation method. The size of silvernanoparticle ranged from 3.5 nm to 5.9 nm. To check the effect of the capability of osseointegration of silvernanoparticle coated Implant, 32 implants (16 piece of Implant treated with nanoparticle, and 16 piece of Implant was not treated for control) were placed at both the tibia of 8 New Zealand white rabbits. After 4 weeks, 4 rabbits were sacrificed and the removal torque was measured for comparison of the osseointagration ability. Further, 4 rabbits were sacrificed and sliced samples were made. H&E stain was done for microscopic finding. Results: The removal torque of the experimental group was $102.37{\pm}30.54$ N/cm, and the control group was $73.30{\pm}19.97$ N/cm. It was statistically significant (P<0.001). Microscopic finding also shows extinguish results in silvernanoparticle treated implants. Bone formation rate of the experimental group was 43.94% and the control group was 7.58%. It was observed to be statistically significant (P=0.017). Bone to implant contact rate of the experimental group was 58.09%, and the control group was 19.43%. It was found with statistical significance (P<0.001). Conclusion: The silvernanopartilce treated implant shows a better capability of bone regeneration and osseointegration than the non-treated one. Technology to produce smaller particles would make silver more useful and safer.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제34권5호
• /
• pp.326-331
• /
• 2012

Purpose: Length measurement from maxillary anterior teeth root tip to nasal floor is incorrect in panoramic radiography. Comparison of cone beam computed tomography (CBCT) and panoramic radiography should be helpful in determining the vertical length. Methods: Sixty nine patients were taken CBCT and panoramic radiography of the maxillary anterior. First measurement is length of parallel lines from the central incisor and lateral incisor root tip to nasal floor on CBCT. Second measurement is length of perpendicular lines from the central incisor and lateral incisor root tip to nasal floor on CBCT. Third measurement is length from the central incisor and lateral incisor root tip to nasal floor on panoramic radiographys. Results: In the first measurement of the maxillary central incisors, an average of $11.36{\pm}2.49$ mm in males and $10.49{\pm}2.17$ mm in females. In the second measurement of the maxillary central incisors, $10.41{\pm}2.42$ mm in males and $9.18{\pm}2.08$ mm in females. In the third measurement of the maxillary central incisors, $10.71{\pm}2.20$ mm in males and $9.27{\pm}2.10$ mm in females. In the first measurement of the maxillary lateral incisors, an average of $13.40{\pm}2.04$ mm in males and $11.96{\pm}2.20$ mm in females. In the second measurement of the maxillary lateral incisors, $11.25{\pm}1.82$ mm in males and $10.06{\pm}1.68$ mm in females. In the third measurement of the maxillary lateral incisors, $11.47{\pm}2.01$ mm in males and $10.13{\pm}1.70$ mm in females. Conclusion: The vertical length from root tip to nasal floor was longer in male than female (P>0.05). First measurement was longer than third measurement (P<0.05). This is the actual placement of the implant site measured on the vertical length than the length of the panorama means that there are a few more free. The first measurement was longer than 114% over the third measurement.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제34권5호
• /
• pp.332-336
• /
• 2012

Purpose: The third molar extraction is one of the mostly performed procedures in the department of oral and maxillofacial surgery. In most of dental clinic or hospital, the third molar extraction used to be frequently performed in an office-based surgery, and most patients did not have specific medical history with young ages. Medical history taking are dependent on the only way by asking to the patients about their individual conditions. Therefore, as the specialists of the oral and maxillofacial surgery in the field of dentistry, we suggest a new policy that the preoperative lab must be performed routinely before extraction of the third molar. Methods: This study is based on 1,096 patients who have been managed with third molar extractions, from March 2008 to September 2011 by a single surgeon. The preoperative lab, including complete blood count, coagulation panel, chemistry and serology, was performed before any surgical procedures. The results were informed to the patients regardless of their abnormalities, and any abnormalities related to the surgical procedures, such as platelet count and coagulation factors, were checked and corrected safely. Results: Through the preoperative blood test, systemic diseases that the patients had not recognized before, such as anemia, leukopenia, fatty liver and chronic renal disease, were identified. Patients with acute or chronic leukemia, Hepatitis B, and HIV positive, were also detected as a small number. Also, the possibilities of the cross-infection between dentists and patients or between patients and patients, and any other emergency situations can be prevented; as well as the public health condition can be improved, too. The patients were satisfied with low cost preventive blood test and high quality of medical services. Conclusion: Therefore, routine medical lab testing, including history taking are needed before an office-based minor surgery, such as third molar extractions, and these results were suggested as a new policy in the field of dentistry.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제34권5호
• /
• pp.311-319
• /
• 2012

Purpose: The aim of this study is to evaluate the vertical changes of the lip and perioral soft tissue, following orthognathic surgery in skeletal class III patients by a cephalometric analysis of a cone beam computed tomography (CBCT). Methods: A total of 20 skeletal class III patients, who had bimaxillary surgery with Le Fort 1 osteotomy and bilateral sagittal split ramus osteotomy, were included in this study. The surgical plan for maxilla was posterosuperior impaction with the anterior nasal spine, as the rotation center. Further, the surgical plan for mandible was also posterosuperior movement. The soft tissue changes between lateral cephalogram and CBCT were compared. And the correlations between independent variables and dependent variables were evaluated. Results: There were no significant differences of the soft tissues changes between lateral cephalogram and CBCT. Upper lip philtrum length (SnLs), nasolabial angle increased and upper lip vermilion length (LsStms), lower lip length (StmiB'), lower lip vermilion length (StmiLi), lower lip philtrum length (LiB') and soft tissue lower facial height (SnMe') decreased after surgery. Change of SnLs (${\Delta}$SnLs) was influenced by vertical change of menton (${\Delta}$MeV), and change of LsStms (${\Delta}$LsStms) was influenced by upper lip thickness (ULT). Change of StmiLi' (${\Delta}$StmiLi') were influenced by preoperative overjet. Change of StmiB' (${\Delta}$StmiB') were influenced by preoperative overjet, vertical change of lower incisor (${\Delta}$L1V) and horizontal change of posterior nasal spine (${\Delta}$PNSH). Change of LiB' (${\Delta}$LiB') was influenced by ${\Delta}$L1V and ${\Delta}$PNSH. Change of SnMe' (${\Delta}$SnMe') was influenced by ${\Delta}$MeV, horizontal change of upper incisor (${\Delta}$U1H) and horizontal change of lower incisor (${\Delta}$L1H). ${\Delta}$Nasolabial angle was influenced by change of ULT (${\Delta}$ULT). Conclusion: Both soft tissues and hard tissues can be evaluated by CBCT. Posterosuperior rotation of maxillomandibular complex resulted in increase of upper lip philtrum length and nasolabial angle, while the upper lip vermilion length, lower lip philtrum length, lower lip vermilion length, and soft tissue lower facial height showed a decrease.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제33권6호
• /
• pp.497-504
• /
• 2011

Purpose: Patients who had a subcondylar fracture with a displaced or deviated condylar segment were treated with a retromandibular approach (RMA) or an endoscope-assisted transoral approach (EATA) in our department of oral and maxillofacial surgery. The clinical results of the approaches were compared. A comparative study of specific approaches for subcondylar fractures has not been published before in Korea. Methods: Twenty-one patients with subcondylar fractures of the mandible were included. Ten patients were treated with the retromandibular approach and 11 were treated with an endoscope-assisted transoral approach. We examined patient age, gender, fracture sites, classifications, period of maxillomandibular fixation, facial nerve (FN) or greater auricular nerve (GAN) injuries, maximal mouth opening, deflection, occlusal changes, number of plates, follow-up period, and other complications. Preoperative computed tomography and pre-operative, post-operative, and follow-up panoramic views were taken of each patient. Results: Mean maximal mouth openings were similar between the two approaches. FN and GAN injuries were more frequent in the RMA group but the deflective rate with mouth opening was higher in the EATA than that in RMA group. Two cases of post-operative infection occurred in the EATA group, and occlusal changes were observed in one case for both approaches. Conclusion: The RMA offers more direct access and visualization of the surgical field but it can cause scars and retractive injuries of the FN and GAN. But, EATA did not result in consequent nerve injuries or scars postoperatively, but unfavorable fractures such as $medial$ $override$ condyles were more difficult to reduce endoscopically. Except cases of an expected difficult reduction, the treatment of choice for a displaced subcondylar fracture may be an EATA.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제32권3호
• /
• pp.207-217
• /
• 2010

The purpose of this study was to evaluate the effects of the stress distribution and displacement in mandible according to treatment modalities of mandibular angle fractures, using a three dimensional finite element analysis. A mechanical model of an edentulous mandible was generated from 3D scan. A 100-N axial load and four masticatory muscular supporting system were applied to this model. According to the number, location and materials of titanium and biodegradable polymer plates, the experimental groups were divided into five types. Type I had a single titanium plate in the superior border of mandibular angle, type II had two titanium plates in the superior tension border and in the inferior compression border of mandibular angle, type III had a single titanium plate in the ventral area of mandibular angle, type IV had a single biodegradable polymer plate in the superior border of mandibular angle, type V had a single biodegradable polymer plate in the ventral area of mandibular angle. The results obtained from this study were follows: 1. Stress was concentrated on the condylar neck of the fractured side except Type III. 2. The values of von-Mises stress of the screws were the highest in the just-posterior screw of the fracture line, and in the just-anterior screw of Type III. 3. The displacement of mandible in Type III was 0.04 mm, and in Type I, II, IV, and V were 0.10 mm. 4. The plates were the most stable in the ventral area of mandibular angle (Type III, V). In conclusion, the ventral area of mandibular angle is the most stable location in the fixation of mandibular angle fractures, and the just- posterior and/or the just-anterior screws of the fracture line must be longer than the other, and surgeons have to fix accurately these screws, and the biodegradable polymer plate also was suitable for the treatment of mandible angle fracture.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제31권6호
• /
• pp.478-484
• /
• 2009

Three-dimensional porous scaffolds play an important role in tissue engineering strategies. They provide a void volume in which vascularization, new tissue formation, and remodeling can occur. Like any grafted materials, the ideal scaffold for bone tissue engineering should be biocompatible without causing an inflammatory response. It should also possess biodegradability, which provides a suitable three-dimensional environment for the cell function together with the capacity for gradual resorption and replacement by host bone tissue. Various scaffolds have already been developed for bone tissue engineering applications, including naturally derived materials, bioceramics, and synthetic polymers. The advantages of biodegradable synthetic polymers include the ability to tailor specific functions. The purpose of this study was to examine the osteogenic activity of periosteal-derived cells in a polydioxanone/pluronic F127 scaffold. Periosteal-derived cells were successfully differentiated into osteoblasts in the polydioxanone/pluronic F127 scaffold. ALP activity showed its peak level at 2 weeks of culture, followed by decreased activity during the culture period. Similar to biochemical data, the level of ALP mRNA in the periosteal-derived cells was also largely elevated at 2 weeks of culture. The level of osteocalcin mRNA was gradually increased during entire culture period. Calcium content was detactable at 1 week and increased in a time-dependent manner up to the entire duration of culture. Our results suggest that polydioxanone/pluronic F127 could be a suitable scaffold of periosteal-derived cells for bone tissue engineering.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제31권6호
• /
• pp.461-468
• /
• 2009

Purpose: Platelet derived growth factor(PDGF)-BB and bone morphogenetic protein(BMP)-2 are well-known representative growth factors. The purposes of this study were to investigate the effect of rhPDGFBB and rhBMP-2 on osseointegration of titanium implants at periimplant bone defects grafted with hydroxyapatite and to evaluate the feasibility of imaging bone structures around screw-type titanium implant with micro-CT. Materials and Methods: The first molar and all premolars in the mandible region of four beagle dogs were extracted. Following a healing period of 4 months, three $8{\times}8{\times}6mm$-sized bony defects were formed and screw-type titanium implants were placed with hydroxyapatite(HA) block and growth factors; Control group, PDGF group and BMP group. Two months post-implantation, the mandible was harvested. Bone volume(BV), bone-to-implant contact(BIC) and bone mineral density(BMD) were analyzed with micro-CT and histology. Results: According to micro-CT analysis, BV and BMD measures of PDGF and BMP group were significantly higher than control group(BV; PDGF group: $p{\fallingdotseq}0.011$, BMP group: $p{\fallingdotseq}0.006$/BMD; PDGF group: $p{\fallingdotseq}0.020$, BMP group: $p{\fallingdotseq}0.011$) and BIC measures of BMP group were significantly higher than PDGF group($p{\fallingdotseq}0.015$). In histologic evaluation, BIC measures of BMP group was significantly higher than PDGF group($p{\fallingdotseq}0.048$). The values of BV in histologic sections were higher than in micro-CT images and the values of BIC in micro-CT images were higher than in histologic sections. Conclusion: The findings of this experimental study indicates that the use of rhPDGF-BB and rhBMP-2 can increase new bone formation in a large bony defect around titanium implant, and rhBMP-2 is more effective than rhPDGF-BB. Micro-CT can be considered useful for assessment as a rapid and nondestructive method for 3-dimensional measurement of bone healing around implants. Further study is necessary, however, to remove metal artifacts around titanium implant and to standardize the method.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제31권6호
• /
• pp.453-460
• /
• 2009

Background and Purpose: Vascular endothelial growth factor (VEGF)-C, VEGF-D and their tyrosine kinase receptor, VEGF receptor (VEGFR)-3 are recently known to have lymphangiogenic activities in various tumor types. Oral mucosal squamous cell carcinoma (OMSCC) easily metastasizes to cervical lymph nodes, so we determined the expression levels of VEGF-C, VEGF-D and VEGFR-3 in oral squamous cell carcinoma. Materials and Methods: We performed Western blot analyses with 4 OMSCC cultured tumor cell lines (SCC9, KB, YD-10B, YD-38), and with 7 surgical specimens of OMSCC for the detection of VEGF-C, VEGF-D and VEGFR-3 proteins. Expression of VEGF-C mRNA as well as mRNA for VEGFR-3 in 4 OMSCC cell lines (KB, SCC-4, SCC-9, YD-10B) was investigated by RT-PCR. We also measured VEGFC/VEGF-D protein concentrations in the media and protein concentration of VEGFR-3 in cell lysates of 4 OMSCC cell lines (SCC9, KB, YD-10B, YD-38) using commerical ELISA kits. Finally, we performed immunoprecipitation for the detection of VEGF-C in cell lysates of 4 OMSCC cells (KB, SCC-4, SCC-9, YD-10B) and real-time RT-PCR for the quantification of VEGF-C mRNA. Results: In the result of Western blotting with cell lysates of 4 OMSCC cells, we could not detect the protein expression of VEGF-C, VEGF-D, and VEGFR-3. But, all tumor tissues demonstrated VEGF-C and VEGFR-3. VEGF-C mRNA was detected at various levels in 4 OMSCC cell lines. Moreover, OMSCC cells secreted VEGF-C, not VEGF-D and VEGFR-3 was also detected in cell lysates of OMSCC by ELISA. Immunoprecipitation and real-time RT-PCR revealed VEGF-C was also expressed in 4 OMSCC cell lines. Conclusion: Taken together, tumor cells of OMSCC secrete VEGF-C, not VEGF-D. And VEGFR-3 is expressed tumor cells as well as OMSCC tumor tissues, needs further study.