Retrospective analysis on prognosis of oral cancer patients according to surgical approaches for effective cancer ablation: swing approach versus visor approach.

BACKGROUND: For the surgical treatment of oral cancer, it is sometimes necessary to expand intraoral access within the oral cavity. The "swing approach" that involves lip splitting of the mandible and temporary mandibular osteotomy and the "visor approach" that does not split the lower lip and mandible are mainly used. This study analyzed postoperative outcomes such as complications, recurrence rate, and survival rate by these two approaches. The goal of this study is to evaluate the surgical outcomes of patients using these two approaches, to propose effective perioperative management for oral cancer surgery, and to compare the prognosis of oral cancer patients. MATERIALS AND METHODS: From 2005 to 2020, 29 patients who underwent surgery at the Department of Oral and Maxillofacial Surgery of Pusan National University Dental Hospital for oral cancer lesions occurred in the mandible, floor of mouth, and tongue were selected for the study. Based on the surgical approach used, a chart review was conducted on various prognostic clinical factors such as the patients' sex and age, primary site, TNM stage, histopathologic grade, recurrence and metastasis, postoperative survival rate, adjuvant chemo-radiation therapy, satisfaction with aesthetics/function/swallowing, length of hospital stay, tracheostomy and its duration, and neck dissection and its type. Statistical analysis was conducted using SPSS 25.0 (SPSS Inc., Chicago, IL) through Fisher's exact t-test. RESULT: There was no statistically significant difference between two groups in terms of clinical and pathological findings, such as survival rate, the need for adjuvant therapies, and the local recurrence rate. Although better outcomes were observed in terms of function, aesthetics, and postoperative complications in the group with visor approach, there was still no statistically significant difference between two groups. However, the duration of hospital stay was shorter in the visor approach group. CONCLUSION: There was no statistically significant difference in clinical prognostic factors between the swing approach and the visor approach. Therefore, when choosing between the two approaches for the ablation of oral cancer, it is considered to select the surgical priority approach that can be easy access based on the size and location of the lesion. The visor approach had advantages of aesthetics and healing period.

No-ozone cold plasma induces apoptosis in human neuroblastoma cell line via increased intracellular reactive oxygen species (ROS).

BACKGROUND: This study aimed to evaluate the effect of argon-based No-ozone Cold Plasma (NCP) on neuroblastoma cancer cell apoptosis. METHODS: Experiments were performed with SK-N-SH and HS 68. Cell cultures were treated with NCP for 1, 3, and 5 min. NCP was applied using three different strategies: direct NCP application to cell cultures, to only media, and to only cells. Evaluation of cell viability and the level of the reactive oxygen species (ROS) was performed. N-acetyl-L-cysteine (NAC) was also used to antagonize intracellular ROS. Cleaved caspase 3, PARP, aquaporin (AQP) 3 and 8 were detected. RESULTS: NCP induced a gradual decrease in the SK-N-SH cell viability. In contrast, the viability of HS 68 cells did not change. SK-N-SH cells viability was reduced the most when the only media-NCP application strategy was employed. Intracellular ROS levels were significantly increased with time. Cleaved caspase 3 and PARP were increased at 6 h after NCP application. SK-N-SH cells remained viable with NAC after NCP application. AQP 3 and 8 were over-expressed in SK-N-SH cells. CONCLUSION: These findings demonstrate the anti-cancer effect of NCP on neuroblastoma cells. NCP enhanced the selective apoptosis of neuroblastoma cells due to the increased intracellular ROS.

Clinical Analysis of Patients who Underwent Reoperation After Orthognathic Surgery: A 14-Year Retrospective Study.

PURPOSE: The purpose of this study was to analyze the patients clinically who underwent reoperation after certain Orthognathic procedures, and to assess the reoperation rate. Furthermore, the authors also evaluated the incidence of intraoperative and postoperative complications that led to the need for reoperation. METHODS: Total 526 patients were selected who underwent Orthognathic surgery between July 2008 and February 2022 at the Department of Oral and Maxillofacial Surgery in Pusan National University Dental Hospital by single surgeon. All the patients information were extracted from electronic database of our university. Demographic, radiologic, intraoperative, and postoperative data were recorded and compiled. RESULTS: Out of 526 patients, 265 (50.3%) were males and 261 (49.6%) were females. The total number of patients who showed complication is 89 (16.9%) and the patients who underwent reoperation are 17 (3.2%). The common complications that occurred were postoperative sensory disturbance (31; 5.8%), unwanted fractures (17; 3.2%), intraoperative nerve injury (11; 2%), wound dehiscence (11; 2%), infection (10; 1.9%), tooth injury (2; 0.3%), and others (18; 3.4%). The serious complications that led to reoperation include severe bleeding (6; 1.1%), unesthetic results (5; 0.9%), non-union of maxilla (4; 0.7%), and failed osteosynthesis (2; 0.3%). After 2018, all the orthognathic surgeries were performed with the help of virtual surgical planning. After application of virtual surgical planning, the number of patients with complications statistically decreased. CONCLUSION: The present study showed that the reoperation rate after orthognathic surgery was low, this rate was more decreased after applying 3-dimensional virtual surgery and 3-dimensional printed plate, especially in unesthetic cases.

Accuracy of Maxillary Positioning During Orthognathic Surgery: A Comparison of Web-based 3-Dimensional Virtual Surgical Planning and Actual Outcomes.

PURPOSE: To determine the accuracy of planned maxillary positioning by virtual surgery by comparing planned and actual postoperative outcomes. MATERIALS AND METHODS: Twenty patients who underwent 2-jaw orthognathic surgery performed by a single surgeon from May 2017 to December 2020 were the subjects of this retrospective study. The coordinates of reference points in horizontal, sagittal, and coronal planes as determined by virtual surgery were compared with those of actual surgical outcomes. The reference points used were as follows: #16 mesiobuccal cusp tip (#16), #26 mesiobuccal cusp tip (#26), and #11 mesial tip (U1); anterior nasal spine; and posterior nasal spine. Three-dimensional linear distances between the reference point on which virtual surgery was performed and the reference point after the actual operation was calculated. RESULTS: Of the 20 patients, there were 11 males and 9 females of average age 20.65±2.41 years. Three-dimensional printed wafers had high accuracy with a maximum difference of 0.3 mm. No significant difference was observed in horizontal or coronal planes for any reference point, but a significant difference was observed in the sagittal plane. However, positional differences between planned and actual reference points were all <1 mm. CONCLUSIONS: Virtual surgical planning and 3-dimensional printed wafer achieved excellent maxillary positioning accuracies after orthognathic surgery.

Effect of No-ozone Cold Plasma on Regeneration after Crushed Mental Nerve Injury in rats.

Background: This experimental research aimed to determine whether No-ozone Cold Plasma (NCP) has regenerative effect on crushed injured sensory nerves in a rat model (Wistar A) and to evaluate whether NCP can be used as an alternative treatment method for sensory nerve injury in the oral-maxillofacial region. Methods: A total of 10 Wistar A rats were used for this experiment. They were divided into three groups according to whether the mental nerve of the left mandible was injured and NCP was applied or not: group 1 (n=3) (non-mental nerve damage, non-MD) - the left mental nerve was exposed and non-damaged; group 2 (n=3) (mental nerve damage, MD) - the left mental nerve was exposed and damaged, NCP was not applied; and group 3 (n=4) (mental nerve damage and NCP, MD-NCP) - the left mental nerve was exposed and damaged, NCP was applied with regular intervals (three times a week). Results: For the behavior analysis, von Frey test was used. Furthermore, the nerve tissues were examined with hematoxylin and eosin (H&E) staining, and the extent of neurorecovery was evaluated with the immunofluorescence staining of certain markers. The behavioral analysis showed that the function recovery sensory nerve was faster in group 3 (MD-NCP). In the histomorphologic and immunofluorescence analyses, the expression of the factors involved in neurorecovery was much higher in group 3 than in group 2 (MD). Conclusions: The expeditious recovery of sensory nerve function as well as the higher expression of the factors indicating nerve function recovery in the NCP-treated group suggest that NCP has a positive effect on regeneration after sensory nerve crushing injury. Therefore, in the case of sensory impairment of the oral-maxillofacial region, no-ozone cold plasma can be applied for therapeutic effect.

Anti-Cancer Activity of the Combinational Treatment of Noozone Cold Plasma with p-FAK Antibody-Conjugated Gold Nanoparticles in OSCC Xenograft Mice.

Oral squamous cell cancer (OSCC) is the most common type of oral cancer (about 80-90% of cases) and various research is being done to cure the disease. This paper aims to verify whether treatment with no-ozone cold plasma (NCP), which is designed for safe usage of the plasma on oral cavities, in combination with gold nanoparticles conjugated with p-FAK antibody (p-FAK/GNP) can trigger the selective and instant killing of SCC-25 cells both in vitro and in vivo. When SCC25 and HaCaT cells are exposed to p-FAK/GNP+NCP, the instant cell death was observed only in SCC25 cells. Such p-FAK/GNP+NCP-mediated cell death was observed only when NCP was directly treated on SCC25 harboring p-FAK/GNP. During NCP treatment, the removal of charged particles from NCP using grounded electric mesh radically decreased the p-FAK/GNP+NCP-mediated cell death. This p-FAK/GNP+NCP-mediated selective cell death of OSCC was also observed in mice xenograft models using SCC25 cells. The mere treatment of p-FAK/GNP and NCP on the xenograft tumor slowly decreased the size of the tumor, and only about 50% of the tumor remained at the end of the experiment. On the other hand, 1 week of p-FAK/GNP+NCP treatment was enough to reduce half of the tumor size, and most of tumor tissue had vanished at the end. An analysis of isolated tissues showed that in the case of individual treatment with p-FAK/GNP or NCP, the cancer cell population was reduced due to apoptotic cell death. However, in the case of p-FAK/GNP+NCP, apoptotic cell death was unobserved, and most tissues were composed of collagen. Thus, this paper suggests the possibility of p-FAK/GNP+NCP as a new method for treating OSCC.

Non-thermal plasma directly accelerates neuronal proliferation by stimulating axon formation.

Among the various methods, Non Thermal Plasma (NTP) has been recently introduced and is being studied to recover the damaged nerve. In the recent years, several studies have suggested that NTP accelerates nerve cell regeneration, but the mechanism remains unknown. This study evaluated the effect of NTP on neuronal proliferation in SH-SY5Y (Human neuroblastoma cells) cells differentiated by retinoic acid (RA) and investigated the mechanism by which NTP promotes cell proliferation. We analyzed the morphology of differentiated SH-SY5Y cells, and performed western blot analysis and reverse transcription polymerase chain reaction (RT-PCR). Immunofluorescence analysis was performed in an in vivo study by categorizing Wistar A rats into three groups: non-nerve damage (Non-ND), nerve damage (ND), and nerve damage + NTP treatment (ND + NTP). The cell morphology analysis revealed that the number of cells increased and axonal elongation progressed after NTP treatment. In addition, western blots indicated that tau expression increased significantly after NTP treatment. The RT-PCR results revealed that the expression of tau, wnt3a, and ß-catenin increased after NTP treatment. The in vivo immunofluorescence assay showed that NTP increased the markers for tau and S100B while regulating the over-expression of MAP2 and GAP43. NTP treatment accelerated cell proliferation and regeneration of damaged neurons in differentiated SH-SY5Y cells. These results establish the fact of NTP as a noninvasive and effective treatment for nerve injury.

PD-L1 Expression Correlated with Clinicopathological Factors and Akt/Stat3 Pathway in Oral SCC.

Programmed cell death ligand 1 (PD-L1) is an immune checkpoint molecule that inhibits immune responses. The physiological and prognostic role of the PD-L1 signaling pathway in the oral maxillofacial region is unclear. This study aimed to investigate the role of PD-L1 in the progression of oral squamous cell carcinoma (OSCC). Furthermore, clinicopathological factors related to PD-L1 expression were examined in patients with OSCC through immunohistochemistry (IHC) of tissue sections and through an in vitro study in OSCC cells. The medical records, radiographic findings, and mortality referrals of 81 patients obtained from the National Statistical Office were reviewed. IHC was performed on tissue specimens of these patients to determine the expression levels of PD-L1, which showed significant statistical differences based on age, tumor size, TNM stage, cervical lymph node metastasis, and locoregional recurrence. Patients with a high PD-L1 expression had significantly poorer survival rates. Multivariate analysis using the Cox proportional model confirmed the high relative risk ratio for high PD-L1 expression, TNM stage, and neck node metastasis, all of which were significantly associated with a poor prognosis in patients with OSCC. The in vitro study showed that SAS and YD38 cells transfected with PD-L1 siRNA had significantly increased apoptosis, reduced proliferative capacity, and tumorigenicity.

Complications According to the Handling of the Pterygoid Plate During Bimaxillary Surgery.

BACKGROUND: During bimaxillary surgery, manipulation of the pterygoid plate is required to facilitate movement of the maxilla. This study examined the complications that occurred after handling the pterygoid plate during a Le Fort I osteotomy. PATIENTS AND METHODS: This study compared and analyzed complications according to the pterygoid plate handling method in 80 patients who underwent bimaxillary surgery at Pusan National University Dental Hospital from December 2015 to July 2020. The pterygoid plate was fractured or removed intentionally only if it interfered with the maxilla. Otherwise, it was not treated. The complications during surgery and the follow-up period were investigated. RESULTS: Fourteen patients experienced complications, of which excessive bleeding, hearing problems, and nonunion were encountered in 10, 2, and 2 patients, respectively. Of the 10 patients with excessive bleeding patients, the pterygoid plate was manipulated in 8 patients, which was controlled during surgery. Two patients complained of hearing loss with ear congestion immediately after surgery; both patients improved spontaneously within 1 month. Two nonunion patients underwent plate refixation at least 6 months postoperatively, and normal healing was achieved afterward. CONCLUSIONS: Fracture and removal of the pterygoid plate during orthognathic surgery did not significantly affect the occurrence of complications during and after surgery.

Delayed Soft Tissue Changes after Clockwise Rotation of the Maxillo-Mandibular Complex.

OBJECTIVE: The purpose of this study was to evaluate delayed soft tissue changes of the maxilla-mandibular complex MMC using three-dimensional (3D) cone-beam computed tomography after clockwise repositioning orthognathic surgery. METHODS: This study included 21 patients that underwent maxilla-mandibular complex clockwise rotational orthognathic surgery by 1 doctor from January 2015 to June 2019. Radiographic images (panorama, lateral cephalogram, posteroanterior view, and conebeam computed tomography) were taken and 3D analysis was performed using the Invivo 5 (Anatomage Inc, Santa Clara, CA) to acquire 3D images before surgery, immediately after surgery, at 6 months after surgery and 21 months after surgery. The 9 soft tissue landmarks were measured and compared in terms of postoperative changes in transverse, vertical, and anteroposterior directions. The points were at the outer commissure of the eye fissure (Exocathion; Exc_r, Exc_l), at the midline of both the nasal root and the nasofrontal suture, analogous to bony N (soft tissue nasion; N), the most prominent point on the nasal tip (Pronasale; Prn), the most lateral point in the curved baseline of each ala, indicating the facial insertion of the nasal wing base (Alare curvature; Ac_r, Ac_l), the most lateral point on the soft tissue contour of each mandibular angle (Soft tissue Gonion; Go_r, Go_l), and the most inferior midpoint on the soft tissue contour of the chin (soft tissue menton; Me). RESULTS: The most prominent point of the nasal tip (Prn) moved 1.36 mm upward and 1.55 mm forward in the vertical and anteroposterior planes immediately after surgery. However, there were no significant changes in Ac_r and Ac_l even immediately after surgery. Both soft tissue gonions shifted downward and forward between immediately after surgery and 6 months after surgery. However, no significant change was observed in the value of any of the 9 soft tissue points between 6 months and 21 months after surgery ( P value < 0.05). CONCLUSIONS: No significant changes were observed between 6 and 21 months after surgery, which suggests no delayed soft tissue changes occur in surgically treated patients after the resolution of surgically-related facial edema and swelling and postsurgical remodeling of hard tissue in overlying soft tissue.

Management of Mandibular Subcondylar Fracture Through an Intraoral Approach Using a Trans-Buccal Trocar With Ramus Buccal Decortication.

PURPOSE: The aim of this study was to review retrospectively the functional recoveries of subcondylar fracture patients that underwent open reduction surgery using an extraoral approach or an intraoral approach using a trans-buccal trocar and involving ramus buccal decortication. MATERIALS AND METHODS: Of 47 patients with mandibular condyle fracture who visited Pusan National University Dental Hospital Department of Oral and Maxillofacial Surgery between May 2015 and November 2020, 38 patients underwent open reduction and were classified according to the surgical method used. Preauricular, submandibular, and retro-mandibular approaches were all classified as extraoral approaches condyle fractures were classified as described by Spiessl and Schroll (1972). Distances between bone fragments on panorama radiographs before and after surgery were measured. RESULTS: Thirty-eight patients were included in this study, 9 patients received subcondylar fracture surgery. Open reduction surgery using an extraoral approach had a greater mean operation time than the intraoral approach using a trocar. Of the 17 patients treated with an intraoral approach, the average distance between bone fragments right after surgery was 1.27 ± 1.41mm, which was significantly greater than that of the extraoral approach (0.72 ± 0.35 mm). CONCLUSIONS: Favorable results can be obtained by mandibular condylar fracture surgery through an intraoral approach using a trans-buccal trocar with ramus buccal decortication. This technique minimizes scarring, secures accessibility using a trocar, and sufficiently secures the field of view through buccal cortical bone reduction.

Skeletal Stability of Two-Jaw Surgery Without Bone Grafting in Patients With Cleft Lip and Palate.

PURPOSE: The purpose of this study was to evaluate the postoperative skeletal stability of orthognathic surgery performed without a bone graft in cleft lip and palate patients. PATIENTS AND METHODS: Nineteen cleft lip and palate patients that underwent orthognathic surgery from July 2008 to August 2019 at the Department of Oral and Maxillofacial Surgery of Pusan National University Dental Hospital were selected. None of these patients underwent bone grafting during orthognathic surgery. Lateral cephalograms were taken 1 month before surgery (T0), immediately after surgery (T1), and 6 months after surgery (T2). Lateral cephalograms were analyzed using the V-Ceph program. The analysis was performed using SPSS for Windows version 26.0. The analysis was conducted by repeated-measures analysis of variance. RESULTS: A total of 19 patients were included in this retrospective study (9 males/10 females of overall mean age 22 ±â€Š4.89 years). Mean maxillary depth values at the 3-time points were 85.37°â€Š±â€Š2.62° (T0), 90.13°â€Š±â€Š2.77° (T1), and 89.29°â€Š±â€Š2.91° (T2). Mean McNamara-N Perpend values were -5.52 ±â€Š3.19 mm (T0), 0.09 ±â€Š3.10 mm (T1), and -0.83 ±â€Š3.14 mm (T2). Mean sella nasion point A (SNA) values were 75.42°â€Š±â€Š2.98° (T0), 79.19°â€Š±â€Š2.94° (T1), and 78.45°â€Š±â€Š2.84° (T2). Mean relapse rates were maxillary depth 20.15%, McNamara-N Perpend 17.95%, and SNA 18.74%. Mean horizontal advancement was 5.61 ±â€Š2.32 mm based on McNamara vertical to A point, mean horizontal relapse was -0.92 ±â€Š0.56 mm, and the mean horizontal relapse rate was 17.95%. CONCLUSIONS: Favorable skeletal stability can be obtained without bone graft when the amount of maxillary advancement is less than 6 mm in cleft patients.

Correlation Between Sports-Related Maxillofacial Injuries and Head Injuries: A Five-Year Retrospective Study.

PURPOSE: As sports have become more diverse and demanding, the number of patients with a maxillofacial injury accompanied by a cranial injury or neurological symptoms has increased. This study examined the correlation between sports-related maxillofacial injuries and head injuries. PATIENTS AND METHODS: Among the patients who visited the emergency department of Pusan National University Dental Hospital due to a maxillofacial injury from sporting activities between 2014 and 2018, those who additionally had head injuries were retrospectively examined. Sporting activities were classified according to the American Academy of Pediatrics classification, and severity of injuries was determined using the Facial Injury Severity Scale (FISS). Patients whose medical records showed neurological symptoms and who underwent brain computed tomography for concomitant head injury were selected. The association between each of these variables, including age and gender, was statistically analyzed. RESULTS: A total of 95 patients were included in this study, most of whom were male teenagers, and cycling was the most common cause of injuries. The meanFISS score was 0.79. Brain computed tomography was conducted for 91 patients, and 28 patients reported neurological symptoms. Only 11 patients underwent advanced evaluation in the neurology or neurosurgery department. Most patients were diagnosed with contusion and concussion and were monitored without any treatment. CONCLUSIONS: Higher FISS values did not reflect the severity of maxillofacial and head injury. In this study, there were some patients with cranial fracture and cerebral hemorrhage with mild neurosurgical symptoms of facial trauma. Although the incidence of head trauma is not high, the necessity of wearing protective equipment cannot be overemphasized because severe trauma is permanent. Neurological signs and symptoms of patients with maxillofacial trauma should not be overlooked and require a thorough evaluation.

Skeletal Stability after Mandibular Setback via Sagittal Split Ramus Osteotomy Verse Intraoral Vertical Ramus Osteotomy: A Systematic Review.

PURPOSE: The purpose of present study was to review the literature regarding the postoperative skeletal stability in the treatment of mandibular prognathism after isolated sagittal split ramus osteotomy (SSRO) or intraoral vertical ramus osteotomy (IVRO). MATERIALS AND METHODS: The articles were selected from 1980 to 2020 in the English published databases (PubMed, Web of Science and Cochrane Library). The articles meeting the searching strategy were evaluated based on the eligibility criteria, especially at least 30 patients. RESULTS: Based on the eligibility criteria, 9 articles (5 in SSRO and 4 in IVRO) were examined. The amounts of mandibular setback (B point, Pog, and Me) were ranged from 5.53-9.07 mm in SSRO and 6.7-12.4 mm in IVRO, respectively. In 1-year follow-up, SSRO showed the relapse (anterior displacement: 0.2 to 2.26 mm) By contrast, IVRO revealed the posterior drift (posterior displacement: 0.1 to 1.2 mm). In 2-year follow-up, both of SSRO and IVRO presented the relapse with a range from 0.9 to 1.63 mm and 1 to 1.3 mm respectively. CONCLUSION: In 1-year follow-up, SSRO presented the relapse (anterior displacement) and IVRO posterior drift (posterior displacement). In 2-year follow-up, both of SSRO and IVRO showed the similar relapse distances.

Practical utility of the three-dimensional approach in orthognathic surgery.

During recent decades, the three-dimensional (3D) approach in orthognathic surgery were introduced and adopted in clinical practice, providing practical advantages to orthognathic surgeons. Even when the 3D approach is assessed based on the current state of technological development, it has advantages in orthognathic surgery and has become an essential method. It is not sure what to come next in the development of the 3D approaches, It is clear that the 3D approach represents a milestone in the development of orthognathic surgery.

Comparison of time and cost between conventional surgical planning and virtual surgical planning in orthognathic surgery in Korea.

BACKGROUND: The purpose of this study was to measure the time of the conventional surgical planning (CSP) and virtual surgical planning (VSP) in orthognathic surgery and to compare them in terms of cost. MATERIAL AND METHOD: This is a retrospective study of the patients who underwent orthognathic surgery at the OOOOO University Dental Hospital from December 2017 to August 2018. All the patients were analyzed through both CSP and VSP, and all the surgical stents were fabricated through manual and 3-dimensional (3D) printing. The predictor variables were the planning method (CSP vs. VSP) and the surgery type (group I: Le Fort I osteotomy+bilateral sagittal split osteotomy [LFI+BSSO] or group II: only bilateral sagittal split osteotomy [BSSO]), and the outcomes were the time and cost. The results were analyzed using paired t test. RESULTS: Thirty patients (12 females, 18 males) met the inclusion criteria, and 17 patients were excluded from the study due to missing or incomplete data. There were 20 group I patients (LFI+BSSO regardless of genioplasty) and 10 group II patients (BSSO regardless of genioplasty). The average time of CSP for group I was 385±7.8 min, and that for group II was 195±8.33 min. The time reduction rate of VSP compared with CSP was 62.8% in group I and 41.5% in group II. On the other hand, there was no statistically significant cost reduction. CONCLUSIONS: The time investment in VSP in this study was significantly smaller than that in CSP, and the difference was greater in group I than in group II.

Sequential treatment from mandibulectomy to reconstruction on mandibular oral cancer - Case review II: mandibular anterior and the floor of the mouth lesion of basaloid squamous cell carcinoma and clear cell odontogenic carcinoma.

Preoperative patient analysis for oral cancer involves multiple considerations that are based on multiple factors; these include TNM stages, histopathologic findings, and adjacent anatomical structures. Once the decision is made to excise the lesion, the margin of dissection and its extent should be considered along with the best form of reconstruction and airway management. Treatment methods include surgical resection, radiotherapy, and chemotherapy. Although the combined method of treatment is controversial, surgical resection is considered predominantly, and immediate reconstruction after surgical resection follows. The choice of treatment is dictated by the anticipated functional and esthetic results of treatment and also by the availability of a surgeon with the required expertise. Segmental mandibulectomy with primary reconstruction has been shown to have advantages in both functional and esthetic results. A 52-year-old male patient with basaloid squamous cell carcinoma of the floor of the mouth, and the anterior portion of the mandible was treated with surgical procedures that included segmental mandibulectomy with both supraomohyoid neck dissection (SOHND) at Levels I-III and mandible reconstruction with a left fibula free flap. A 55-year-old male patient with clear cell odontogenic carcinoma of the oral cavity underwent segmental mandibulectomy with both SOHND at Levels I-III and mandible reconstruction with a left fibula free flap. The purpose of this study was to review the anatomic and functional results of patients after immediate reconstruction with a fibula free flap following resection of carcinoma in the anterior portion of the mandible and floor of the mouth.

The effect of autogenous tooth bone graft material without organic matter and type I collagen treatment on bone regeneration.

OBJECTIVES: The aim of this study is to examine the effect of particulate autogenous tooth graft removed with organic matter and type I collagen addition on bone regeneration and to validate the possibility of useful allograft material for jaw defects. MATERIAL AND METHODS: Autogenous tooth bone maker (Korean Dental Solution® KOREA) made particulate autogenous tooth not including organic matter. We used to the developed tooth grafts for experiment. Cell adhesion test with hemacytometer and energy dispersive X-ray spectroscopy (Supra40 VP®, Carl Zeiss, Germany) analysis about the particulate autogenous tooth and type I collagen were performed. Rabbits were divided into three groups: bone graft with organic matter (OM) removing particulate autogenous tooth group, bone graft with OM removing particulate autogenous tooth and type I collagen group, and a control group. Bone grafting was performed in rabbit's calvaria. The rabbits were sacrificed at different interval at 1, 2, 4, and 6 weeks after bone grafting for the histopathologic observation and observed the effect of bone regeneration by SEM, H-E & Masson stains, osteocalcin IHC staining. RESULT: In vitro cytopathological study showed affinity for cells, cell attachment pattern, and cell proliferation in the order of control group, OM-removed and collagen-treated group, OM-removed particulate autogenous tooth group. The results of the degree of mineralization were opposite to those of the previous cell experimental results, and the OM-removed group, OM-removed group and collagen-treated group were relatively higher than the control group. Histopathologic analysis showed that vascularization and neonatal bone formation were higher in particulate autogenous tooth group with removing OM and with addition of collagen than control group and group of OM removed only. Immunohistochemical analysis showed that osteocalcin (OSC) expression was not observed in the control group, but at 4 weeks groups, OSC expression was observed the OM removed and OM-removed-collagen-treated particulate autogenous tooth, and the degree of expression was somewhat stronger in group of the OM removed and collagen additionally treated particulate autogenous tooth. CONCLUSION: Particles that do not contain organic matter, the saint tooth, was responsible for sufficient bone graft material through the role of space maintenance and bone conduction, and further improved bone formation ability through additional collagen treatment. Therefore, research on various extracellular substrates and autologous bone grafting materials is necessary, and through this, it is possible to lay the foundation for a new type of autologous bone grafting material with excellent academic and technical utility.

Sequential treatment from mandibulectomy to reconstruction on mandibular oral cancer - Case review I: mandibular ramus and angle lesion of primary intraosseous squamous cell carcinoma.

Primary intraosseous squamous cell carcinoma (PIOSCC) is very rare type of squamous cell carcinoma (SCC) that occurs within the jaw and arises from remnants of odontogenic epithelium with no connection to the oral mucosa. This study reports two cases of PIOSCC of the mandible. Reported in this article are two cases of PIOSCC of the mandible that were treated with resection and reconstruction using a fibular free flap. The first case was a 36-year-old male patient who complained of right mandibular pain. Computed tomography (CT) and panoramic radiograph revealed a large radiolucency in the mandibular ramus area. At first, an odontogenic keratocyst was tentatively diagnosed, and an excision procedure was carried out at another clinic. A final biopsy after cyst enucleation revealed well-differentiated SCC, so we proceeded with segmental mandibulectomy and reconstruction using a fibular free flap. The second case was a 48-year-old male patient with left mandibular pain. CT and panoramic radiograph revealed irregular radiolucency in the mandibular angle area near tooth #38. At first, osteomyelitis was tentatively diagnosed, and a curettage was carried out. A later biopsy revealed well-differentiated SCC, so segmental mandibulectomy and reconstruction with a fibular free flap were secondarily performed. Our two cases have had no recurrence. The facial appearance of both patients is satisfactory, and the neo-mandibular body created using a fibular bone transfer displays adequate bony volume.

Non-thermal plasma application enhances the recovery of transected sciatic nerves in rats.

This experimental research aimed to investigate the effects of non-thermal plasma on nerve regeneration after transected nerve damage using the sciatic nerve in Wistar albino (A) rats. The experiments were performed on 27 Wistar A rats. The rats underwent surgery for right sciatic nerve exposure and were divided into three groups (each group, n = 9) according to sciatic nerve transected injury (SNTI) and non-thermal plasma application: a non-nerve damage (non-ND) group, a only nerve damage without non-thermal plasma application (ND) group, and a nerve damage with non-thermal plasma application (ND + NTP) group. Subsequent to SNTI and immediate suture, non-thermal plasma was administered three times per week for eight weeks. Evaluation for functional recovery was performed using the static sciatic index measured over the full treatment period of eight weeks. The sciatic nerve specimens were obtained after euthanasia and third day from the last non-thermal plasma application. The sciatic nerve tissues were subjected to histological analysis. Behavior analysis presented that the ND + NTP group showed improved static sciatic index compared with the nerve damage group. Histopathological findings demonstrated that the ND + NTP group had more dense Schwann cells and well-established continuity of nerve fibers, greater than the nerve damage group. Immunohistochemistry showed that the ND + NTP group had increased levels of markers for microtubule-associated protein 2 (MAP2), tau, S100 calcium-binding protein B, and neurofilament-200 and regulated the overexpression of CD68 and MAP2. These results indicated that non-thermal plasma enhanced the motor function and restored the neuronal structure by accelerating myelination and axonal regeneration. Additionally, non-thermal plasma was confirmed to have a positive effect on the recovery of SNTI in rats.