Effect of 3D-printed polycaprolactone/osteolectin scaffolds on the odontogenic differentiation of human dental pulp cells.

Cell-based tissue engineering often requires the use of scaffolds to provide a three-dimensional (3D) framework for cell proliferation and tissue formation. Polycaprolactone (PCL), a type of polymer, has good printability, favorable surface modifiability, adaptability, and biodegradability. However, its large-scale applicability is hindered by its hydrophobic nature, which affects biological properties. Composite materials can be created by adding bioactive materials to the polymer to improve the properties of PCL scaffolds. Osteolectin is an odontogenic factor that promotes the maintenance of the adult skeleton by promoting the differentiation of LepR+ cells into osteoblasts. Therefore, the aim of this study was to evaluate whether 3D-printed PCL/osteolectin scaffolds supply a suitable microenvironment for the odontogenic differentiation of human dental pulp cells (hDPCs). The hDPCs were cultured on 3D-printed PCL scaffolds with or without pores. Cell attachment and cell proliferation were evaluated using EZ-Cytox. The odontogenic differentiation of hDPCs was evaluated by alizarin red S staining and alkaline phosphatase assays. Western blot was used to evaluate the expression of the proteins DSPP and DMP-Results: The attachment of hDPCs to PCL scaffolds with pores was significantly higher than to PCL scaffolds without pores. The odontogenic differentiation of hDPCs was induced more in PCL/osteolectin scaffolds than in PCL scaffolds, but there was no statistically significant difference. 3D-printed PCL scaffolds with pores are suitable for the growth of hDPCs, and the PCL/osteolectin scaffolds can provide a more favorable microenvironment for the odontogenic differentiation of hDPCs.

Giant cell angiofibroma of gingiva in tuberous sclerosis complex: a case report and literature review.

BACKGROUND: Tuberous sclerosis complex (TSC) is a rare, complex genetic disorder characterized by hamartomas and neoplastic lesions in various organ systems. With the development of radiology and gene testing, the diagnostic criteria for TSC were updated in 2012 at the International Consensus Conference. Intraoral fibromas have long been associated with TSC. However, the incidence of giant cell angiofibroma (GCA) in TSC patients is extremely rare. Here, we report the first case of GCA in the gingival tissue of a patient with TSC. CASE PRESENTATION: A 41-year-old woman first visited the Department of Oral and Maxillofacial Surgery, Chonnam National University Dental Hospital, complaining of gingival enlargement. Clinical examination revealed several manifestations associated with TSC, including intraoral fibromas, facial angiofibromas, dental enamel pits, ungual fibromas, "confetti" skin lesions, hypomelanotic macules, and a shagreen patch. Intraoral examination revealed a 6.0 × 5.0 cm gingival overgrowth on the left mandible. Surgical excision was performed, and subsequent histopathological examination confirmed the diagnosis of GCA. There was no evidence of recurrence within the 24- months of surgery. CONCLUSIONS: We report the first case of GCA in the gingival tissue of a patient with TSC. This report would contribute to an improved understanding of this rare disease. However, further case reports are necessary to clarify the relationship between GCA and TSC.

Transoral Endoscopy-Assisted Tongue-Lip Adhesion With Modified Tongue Base Suspension in a Pierre-Robin Sequence: A Safe and Effective Technique.

Life-threatening airway obstruction is a major concern in patients with Pierre-Robin sequence. Tongue-lip adhesion (TLA) has been used to manage airway obstruction. The authors present the case of a female neonate with Pierre-Robin sequence who presented with airway obstruction and a cleft palate. She underwent a TLA procedure with modified tongue base suspension (TBS). Endoscopy was used to check and control the traction of the tongue base to enable unobstructed self-ventilation. Positive outcomes including improved O2 saturation and weight gain were noted. The effectiveness of TLA was enhanced by using TBS with real-time endoscopy to evaluate the oropharyngeal airway space required to alleviate airway obstruction. The use of endoscopy enabled us to check and determine how much the tongue base should be tracted by manipulating the tongue anteriorly and posteriorly. The authors report transoral endoscopy-assisted TLA and modified TBS.

Condylar volume and positional changes following a bilateral sagittal split ramus osteotomy in skeletal class II and III malocclusions.

BACKGROUND: Mandibular condyle remodeling and displacement are post-orthognathic surgery concerns that can potentially lead to occlusal issues after bilateral sagittal split ramus osteotomy. This retrospective study examined the relationship between condylar volume changes and position alterations after surgery in patients with skeletal class II and III malocclusions using cone-beam CT. METHODS: The study included 16 patients (6 with Class II malocclusion, 10 with Class III malocclusion) who underwent bilateral sagittal split ramus osteotomy at Chonnam National University Hospital. Cone-beam CT data were collected at three specific time points: before surgery, immediately after surgery, and approximately 6 months post-surgery. Mandibular movement was measured using InVivoDental 5.4.6. ITK-SNAP 3.8.0 was used to assessed condylar volume changes post-surgery. Condyle positions were evaluated in four parts with RadiAnt DICOM Viewer 4.6.9. Statistical analyses were performed using the SPSS version 23. RESULTS: Considering both Class II and III malocclusion, a 2.91% volume reduction was noted immediately and at 6 months after surgery. Both Class II and III cases demonstrated a decrease in superior joint space by -0.59 mm and medial joint space by -1.09 mm. No significant correlation was found between this process and condylar volume change. CONCLUSIONS: The mandibular condyle volume decreased, and superior-medial movement of the condyle was detected in patients with Class II and III malocclusion immediately and at 6 months after surgery with no volume-position correlation.

Redox-Sensitive Delivery of Doxorubicin from Nanoparticles of Poly(ethylene glycol)-Chitosan Copolymer for Treatment of Drug-Resistant Oral Cancer Cells.

Reactive oxygen species (ROS)-sensitive polymer nanoparticles were synthesized for tumor targeting of an anticancer drug, doxorubicin (DOX). For this purpose, chitosan-methoxy poly(ethylene glycol) (mPEG) (ChitoPEG)-graft copolymer was synthesized and then DOX was conjugated to the backbone of chitosan using a thioketal linker. Subsequently, the chemical structure of the DOX-conjugated ChitoPEG copolymer (ChitoPEGthDOX) was confirmed via 1H nuclear magnetic resonance (NMR) spectra. Nanoparticles of the ChitoPEGthDOX conjugates have spherical shapes and a size of approximately 100 nm. Transmission electron microscopy (TEM) has shown that ChitoPEGthDOX nanoparticles disintegrate in the presence of hydrogen peroxide and the particle size distribution also changes from a monomodal/narrow distribution pattern to a multi-modal/wide distribution pattern. Furthermore, DOX is released faster in the presence of hydrogen peroxide. These results indicated that ChitoPEGthDOX nanoparticles have ROS sensitivity. The anticancer activity of the nanoparticles was evaluated using AT84 oral squamous carcinoma cells. Moreover, DOX-resistant AT84 cells were prepared in vitro. DOX and its nanoparticles showed dose-dependent cytotoxicity in both DOX-sensitive and DOX-resistant AT84 cells in vitro. However, DOX itself showed reduced cytotoxicity against DOX-resistant AT84 cells, while the nanoparticles showed almost similar cytotoxicity to DOX-sensitive and DOX-resistant AT84 cells. This result may be due to the inhibition of intracellular delivery of free DOX, while nanoparticles were efficiently internalized in DOX-resistant cells. The in vivo study of a DOX-resistant AT84 cell-bearing tumor xenograft model showed that nanoparticles have higher antitumor efficacy than those found in free DOX treatment. These results may be related to the efficient accumulation of nanoparticles in the tumor tissue, i.e., the fluorescence intensity in the tumor tissue was stronger than that of any other organs. Our findings suggest that ChitoPEGthDOX nanoparticles may be a promising candidate for ROS-sensitive anticancer delivery against DOX-resistant oral cancer cells.

Can Fracture Reduction be Attempted Through a 3D-Printed Guide Template Without Maxillomandibular Fixation?

BACKGROUND: Computer-aided design and manufacturing (CAD/CAM) is widely used in clinical practice. This technology may change existing methods for mandibular fracture management. PURPOSE: The purpose of this in-vitro study was to determine if the reduction for mandibular symphysis fracture can be performed without maxillomandibular fixation (MMF) using 3-dimensional (3D)-printed template. STUDY DESIGN, SETTING, AND SAMPLE: This in-vitro study was designed as a proof-of-concept. The sample was composed of 20 existing pairs of intraoral scan and computed tomography (CT) data. A mandibular model stereolithography (STL) file was created by merging the STL file obtained for the bimaxillary dentitions with the CT DICOM file, and this was set as the original model. Using the original model, a STL file of a fracture model of the mandibular symphysis was created using CAD. A template similar to a wafer or an implant guide was manufactured to restore original occlusion, and the mandibular fracture model was reduced and fixed using the 3D-printed template and wire. This was set as the experimental group. The 3D coordinate system error was measured at 6 landmarks and statistically compared using scan data between models of the groups. PREDICTOR/EXPOSURE/INDEPENDENT VARIABLES: Reduction techniques with MMF or without MMF using guide template for mandibular fracture model. MAIN OUTCOME VARIABLE(S): The 3D coordinate system error (mm). COVARIATES: The position of landmarks. ANALYSES: The Mann-Whitney U test, student's t-test, and the Kruskal-Wallis test were used to analyze the coordinate errors between the landmarks. A P value of < .05 was considered statistically significant. RESULTS: The 3D error value of the control and experimental group were 1.06 ± 0.63 mm (range: 0.11 to 2.92 mm) and 0.96 ± 0.48 mm (range: 0.2 to 2.95 mm), respectively. There was no statistical difference between the control and experimental group. There was a statistically significant difference in the lower 2 and lower 3 landmarks compared to the upper 1 (P = .001 and .000, respectively) before and after the reduction in the experimental group. CONCLUSION AND RELEVANCE: This study demonstrates that the reduction using a 3D-printed guide template for the mandibular symphysis fracture could be possible even without the MMF.

Accuracy of digital surgical guides for dental implants.

BACKGROUND: Recently developed imaging techniques, such as cone beam computed tomography (CBCT) and CAD/CAM technology, have facilitated reliable implant planning and implant surgical guide production by 3D printing. This study compared the accuracy of implant-guided surgery using the R2GATE® program with CBCT before and after surgery. PATIENTS AND METHODS: The study included patients who visited the Department of Oral and Maxillofacial Surgery at Chonnam National University Hospital from September 2021 to March 2022. Twenty-four implants were placed in eleven patients. Using R2GATE® Windows (Megagen implant, Daegu, Korea) software, implant placement was planned. The difference was measured by the CBCT before and after surgery. The cervical and apical distance and angular deviation of the implants were measured. Statistical analysis was performed using an independent t-test, Pearson correlation, and multiple regression analyses. RESULTS: The three-dimensional linear distance difference between the planned implant and the placed implant was 0.97 ± 0.37 mm at the cervical and 1.13 ± 0.36 mm at the apical. The difference in angle deviation between the planned implant and the placed implant was 3.42 ± 2.12°. Among the variables affecting the accuracy of implant placement, a statistically significant difference was found when using a tissue-supported implant guide, implant diameter and implant length. CONCLUSION: Based on these results, using the R2GATE® program is useful to use an implant digital surgical guide, and it will be used in various clinic.

Open versus closed treatment for extracapsular fracture of the mandibular condyle.

Objectives: Selection of treatment methods for mandibular condylar fractures remains controversial. In this study, we investigated treatment methods for condylar fractures to determine the indications for open or closed reduction. Patients and. Methods: Patients >12 years of age treated for mandibular condylar fractures with a follow-up period of ≥3 months were included in this study. The medical records of enrolled patients were reviewed for sex, age, fracture site, treatment method (open or closed reconstruction), postoperative intermaxillary fixation period, operation time, and complications. Radiological analysis of fracture fragment displacement and changes in ramal height difference was performed using computed tomography and panoramic radiography. Results: A total of 198 patients was investigated, 48.0% (n=95) of whom underwent closed reduction and 52.0% (n=103) underwent open reduction. There was no significant correlation between reduction method and patient sex, age, or follow-up period. No statistically significant difference between the incidence of complications and treatment method was observed. None of the patients underwent open reduction of condylar head fracture. Binary logistic regression analysis showed that open reduction was significantly more frequent in patients with subcondylar fracture compared to in those with a fracture in the condylar head area. There was no statistically significant correlation between the groups and fracture fragment displacement. However, there was a significant difference between the treatment groups in amount of change in ramal height difference between the fractured and the nonfractured sides during treatment. Conclusion: No significant clinical differences were found between the open and closed reduction methods in patients with mandibular condylar fractures. According to fracture site, closed reduction was preferred for condyle head fractures. There was no significant relationship between fracture fragment displacement and treatment method.

Evaluation of mandibular positional changes after orthognathic surgery in skeletal class II and class III surgery-first approach patients.

PURPOSE: The aim of this study was to predict and compare postoperative changes of mandibular position between mandibular setback and advancement surgery in a surgery-first approach (SFA). MATERIALS AND METHODS: The study population included patients who underwent mandibular setback or advancement surgery using bilateral sagittal split ramus osteotomy, those were divided into two groups: mandibular setback and advancement surgery. Surgical and postoperative mandibular positional changes were evaluated by lateral cephalograms and CTs taken within 2 months before surgery (T0), 1 week after surgery (T1), and after the debonding procedure (T2). The postoperative mandibular positional changes were predicted from the increase in vertical dimension (VD) in surgical occlusion and the counterclockwise rotation to the preoperative VD on the lateral cephalograms and CT at T1. Furthermore, resultant measurement on postoperative mandibular positional changes was performed. Finally, we compared the prediction with actual positional changes of the mandible after the debonding procedure. RESULTS: Nine SFA patients with mandibular setback surgery and six with advancement surgery were evaluated and significant mandibular changes from T0 to T1 and from T1 to T2 were observed. Negative correlation between horizontal surgical changes and postoperative horizontal changes was present in both groups. The difference between the predicted and actual amount of postoperative mandibular movement was significant in the mandibular advancement surgery group. CONCLUSION: Postoperative mandibular relapse appeared much larger in the mandibular advancement surgery group than in the setback group. Therefore, it is more important to consider the postoperative mandibular position change in mandibular advancement surgery in SFA.

Periodontal ligament preloading and rapid prototyping of the donor tooth in the autotransplantation of premolars with complete root formation.

This case report describes the successful orthodontic treatment of an 11-year-old girl with skeletal Class II malocclusion and congenitally missing mandibular second premolars. To resolve her upper lip protrusion and restore the missing mandibular premolars, extraction of the maxillary first premolars and subsequent autotransplantation of the extracted premolars onto the site of the missing mandibular second premolars were performed. To ensure the success of the autotransplantation and subsequent orthodontic treatment, an orthodontic force was preapplied on the donor teeth, and the recipient sockets were prepared with the aid of replica teeth. Thereafter, comprehensive orthodontic treatment was performed to close the extraction space in the maxilla and align the mandibular dentition, including the transplants. The patient achieved a functional occlusion with an improved facial profile. Results of the orthodontic treatment and autotransplantation were stable during the 5-year follow-up. On the basis of this report, a management protocol for a biomechanically enhanced autotransplantation procedure was suggested. This approach would enable an effective treatment procedure, thereby increasing the usefulness of autotransplantation.

Effect of Hydroxyapatite Nanoparticles and Nitrogen Plasma Treatment on Osteoblast Biological Behaviors of 3D-Printed HDPE Scaffold for Bone Tissue Regeneration Applications.

The need for the repair of bone defects has been increasing due to various causes of loss of skeletal tissue. High density polyethylenes (HDPE) have been used as bone substitutes due to their excellent biocompatibility and mechanical strength. In the present study, we investigated the preosteoblast cell proliferation and differentiation on the adding nano-hydroxyapatite (n-HAp) particles into HDPE scaffold and treating HDPE/n-HAp scaffolds with nitrogen (N2) plasma. The three-dimensional (3D) HDPE/n-HAp scaffolds were prepared by fused modeling deposition 3D printer. The HDPE/n-HAp was blended with 10 wt% of n-HAp particle. The scaffold surface was reactive ion etched with nitrogen plasma to improve the preosteoblast biological response in vitro. After N2 plasma treatment, surfaces characterizations were investigated using Fourier transform infrared spectroscopy, scanning electron microscopy, and atomic force microscopy. The proliferation and differentiation of preosteoblast (MC3T3-E1) cells were evaluated by MTT assay and alkaline phosphatase (ALP) activity. The incorporation of n-HAp particles and N2 plasma surface treatment showed the improvement of biological responses of MC3T3-E1 cells in the HDPE scaffolds.

The accuracy of a partially guided system using an in-office 3D-printed surgical guide for implant placement.

AIM: To conduct an observational study evaluating the efficacy of a partially guided system for implant surgery. MATERIALS AND METHODS: The study included 48 implant placements in 24 patients. Following virtual implant planning with designated software, a surgical guide was fabricated using a 3D desktop printer. Each surgically placed implant was compared with its planned position in the software. The coronal and apical distance and angular errors of the implants were evaluated. The correlation between the errors and the variables (residual bone height, surgeon, implant placement site, guide support type, implant diameter) was analyzed using multiple regression analysis. RESULTS: The coronal and apical mean distance errors were 1.28 ± 0.85 and 1.8 ± 0.97 mm, respectively. The mean angular error was 3.66 ± 3.37 degrees. The correlation coefficients (coronal: 0.285; apical: 0.308) indicated a significant linear correlation between the anterior and posterior implant placement positions (P < 0.05). CONCLUSION: A partially guided system with in-office guide fabrication using a 3D desktop printer is a useful option for implant placement.

Effect of rhBMP-2 applied with a 3D-printed titanium implant on new bone formation in rabbit calvarium

Abstract Objective This study sought to compare the biocompatibility of a three-dimensional (3D)-printed titanium implant with a conventional machined titanium product, as well as the effect of such implant applied with recombinant human Bone Morphogenetic Protein Type 2 (rhBMP-2) for guided bone regeneration. Methodology Disk-shaped titanium specimens fabricated either by the conventional machining technique or by the 3D-printing technique were compared by MC3T3-E1 cells cytotoxicity assay. New bone formation was evaluated using a rapid prototype titanium cap applied to the calvaria of 10 rabbits, which were divided into two groups: one including an atelopeptide collagen plug on one side of the cap (group I) and the other including a plug with rhBMP-2 on the other side (group II). At six and 12 weeks after euthanasia, rabbits calvaria underwent morphometric analysis through radiological and histological examination. Results Through the cytotoxicity assay, we identified a significantly higher number of MC3T3-E1 cells in the 3D-printed specimen when compared to the machined specimen after 48 hours of culture. Moreover, morphometric analysis indicated significantly greater bone formation at week 12 on the side where rhBMP-2 was applied when evaluating the upper portion immediately below the cap. Conclusion The results suggest that 3D-printed titanium implant applied with rhBMP-2 enables new bone formation.

Decompression of Large Cyst Invading the Mandibular Canal Leading to Reduced Cyst Volume and Increased Mandibular Canal Length.

PURPOSE: The mandibular canal is damaged by the growth of cysts, and remodeling of the mandibular canal is observed as the size of the cyst decreases after decompression procedures. This study aimed to estimate changes in cyst volume and mandibular canal length using cone-beam computed tomography (CBCT) before and after decompression surgery. MATERIALS AND METHODS: A retrospective cohort study was conducted in patients with a diagnosis of mandibular cyst invading the mandibular canal between 2012 and 2018. All patients underwent CBCT at the initial visit and after decompression. The predictor variable was the period before decompression and before enucleation surgery. The outcome variables were changes in cyst volume and mandibular canal length, which were evaluated 3-dimensionally. The initial volume of the cyst, initial length of the mandibular canal, and patient's age were set as variables of interest that affected the outcome. RESULTS: Decompression was performed in 20 patients (18 male and 2 female patients), and the mean decompression duration was 8.81 ± 2.94 months. The average volume reduction rate after decompression was 60.23%, with an average volume reduction speed of 0.72 mL/month. The average length increase rate after decompression was 50.88%, and the average speed of length increase was 2.68 mm/month. The initial volume of the cyst and initial length of the mandibular canal were the important variables affecting the results. Complete separation of the mandibular canal from the cyst was observed in 11 cases, and incomplete separation was found in 9. CONCLUSIONS: Separation from the cyst and regeneration of the mandibular canal using decompression were observed using 3-dimensional CBCT analysis. The results of this study suggest that decompression is effective in separating and preserving important anatomic structures invaded by the cyst.

Risk factors for postoperative infection of odontogenic cysts associated with mandibular third molar.

BACKGROUND: Odontogenic cysts associated with lower third molar are common. The prognosis for surgical treatment is relatively good. However, postoperative infection discourages the clinicians. Hence, we would like to investigate the factors associated with infection after surgical treatment of cysts associated with the mandibular third molar. METHODS: We retrospectively reviewed the medical and radiographic records of 81 patients who were diagnosed with dentigerous cyst or odontogenic keratocyst and underwent cyst enucleation. The factors affecting postoperative infection were divided into host factor, treatment factor, and cystic lesion factor. To identify the factors associated with postoperative infection, we attempted to find out the variables with significant differences between the groups with and without infection. RESULTS: A total of 81 patients (64 male and 17 female) were enrolled in this study. There was no statistical relationship about the postoperative infection between all variables (gender, smoking, diabetes mellitus, age, bone grafting, related tooth extraction, previous marsupialization or decompression, type of antibiotics, cortical perforation associated with cystic lesion, preoperative infection, preoperative cyst size). CONCLUSIONS: The results of this study suggest that it is not necessary to avoid bone grafts that are concerned about postoperative infection.

Evaluation of implant stability using different implant drilling sequences.

BACKGROUND/PURPOSE: Simplifying the drilling sequence would be meaningful for implant surgery, if it does not exert a negative influence. This prospective clinical study was conducted to evaluate the stability of implant placements after simplifying the drilling sequence. MATERIALS AND METHODS: Subjects were divided into a control group that underwent a normal drilling sequence or a test group that underwent only an initial and final drilling. To evaluate the stability of the placed implant, radiography and implant stability quotient (ISQ) measurements were recorded immediately and 5 months after placement. RESULTS: In all subjects, the prosthesis process was completed with no significant resorption of the marginal bones. In contrast, a statistically significant difference was observed between the control and test groups 5 months after the implants were placed in terms of the ISQ score (80.72 ±â€¯6.76 and 71.83 ±â€¯9.00, respectively); however, both scores were sufficient to proceed with the prosthesis process. CONCLUSION: These attempts to simplify drilling protocols are expected to contribute the improvement of implant-related treatments in future.

The effect of an interfragmentary gap on the clinical outcome after mandibular angle fracture surgery.

BACKGROUND/AIM: The mandibular angle fracture occasionally widens at the lower border after surgery using a single miniplate. However, the effects of an interfragmentary gap have not been fully investigated. The aim of this study was to determine the effects of gaps caused by mandibular angle fracture surgery using a single superior border miniplate technique. MATERIAL AND METHODS: In this prospective study, the interfragmentary gap was measured by panoramic radiography and cone-beam computed tomography (CBCT) postoperatively. The width of the gap measured by panoramic radiography and CBCT scans was compared. The patients were divided into two groups based on the gap width (more or less than 1.5 mm). In CBCT scans, bucco-lingual displacement of the proximal segment was evaluated. Clinical results and complication rates were investigated according to the gap and displacement. The findings were statistically analyzed. RESULTS: Thirty-two patients were included in the study. The mean interfragmentary gap widths were 1.56 ± 0.83 mm by panoramic radiography and 2.12 ± 0.87 mm by CBCT scans. CBCT measured a gap width of approximately 0.5 mm wider than panoramic radiography (P = 0.001). Twenty-two patients (68.8%) had an interfragmentary gap width of >1.5 mm, and ten patients (31.2%) had a gap width of <1.5 mm. All patients had favorable occlusion at the last clinical examination. There were no statistically significant differences in intermaxillary fixation periods and complication rates (P > 0.05). One patient in the wider gap group experienced pain in the temporomandibular joint when opening the mouth. Six patients (18.8%) had lingual displacement of the proximal fragment. Displacement did not significantly influence the complication rate (P > 0.05). CONCLUSION: The presence of an interfragmentary gap after mandibular angle fracture surgery did not affect the clinical outcome.

Alternative Treatment for Blow-In Fracture of Lateral Orbital Wall: Removal of the Fractured Fragment.

Blow-in fracture of the zygomaticomaxillary complex that was displaced into the orbital cavity could be associated with ophthalmologic injuries, ranging from visual acuity to ocular motility limitation. Appropriate reduction and realignment of the fractured bone is necessary as early as possible for recovery of function and esthetics. However, limitation of accessibility and visibility makes it difficult for delicate surgery and increases the risk of damage of adjacent anatomic structures, such as optic nerve and extraocular muscles. In this report, the removal of fractured fragment was carried out in 2 patients showing limitation of gaze via orbital rim approach to avoid aggressive surgery and reduce the possibility of injury of vital structures. The postoperative process was uneventful and there were no complications associated with removal of displaced lateral wall. In conclusion, the authors propose that the removal of the fragment that was medially displaced lateral wall of the orbit is a simple and safe method as an alternative treatment in a difficult situation of reduction surgery.

Bilateral Temporomandibular Joint Replacement Using Computer-Assisted Surgical Simulation and Three-Dimensional Printing.

The dental occlusion is the important reference for replacement of the temporomandibular joint. If a patient does not have normal occlusion, few considerations are needed for temporomandibular joint replacement. The custom-made prosthesis, typically fabricated with a stereolithographic model, is probably the optimized solution currently available. However the ready-made stock from Biomet Microfixation System (Jacksonville, FL) is the only available product, which is authorized by the government ministry in South Korea, for replacement of the temporomandibular joint. This report presents a patient with the problems that were retrognathic "bird face" profile subsequent to severe bilateral condylar resorption and temporomandibular joint ankylosis without enough natural teeth for occlusion. Bilateral temporomandibular joint replacement using the ready-made prosthesis was done by reestablishing the mandibular position with new occlusion and improved facial profile via the virtual surgical planning and stereolithographic model simulation.

Simultaneous surgery for subcondylar fracture and prominent angle of the mandible.

We experienced a patient of subcondylar fracture who had a squared contour of the lower face with prominent angle of the mandible and masseter hypertrophy. Our patient was increasingly seeking esthetic improvement of the lower third of the face. But she did not want multi-stage operations. Thus, we decided and performed a one-stage mandibular angle ostectomy with fracture management. We have a stable and esthetic result simultaneously despite fractures of the fixation plates during follow-up period, so report a case.