Cystic lesion between a deciduous tooth and the succeeding permanent tooth: a retrospective analysis of 87 cases

Objectives@#The purpose of this study is to investigate the characteristics of dentigerous and radicular cysts that occur between deciduous and succeeding permanent teeth and to propose considerations for differential diagnosis of cysts at the treatment planning stage in the outpatient clinic. @*Materials and Methods@#A total of 87 patients with a cystic lesion located between a deciduous tooth and the succeeding permanent tooth participated in the study. Twelve variables were analyzed to diagnose such a cyst. For data analysis, Fisher’s exact test was used to determine the statistical significance of the variables. @*Results@#Of the total 87 patients who participated in this study, 69 were diagnosed with dentigerous cysts and 18 were diagnosed with radicular cysts.Seven of the 12 differential factors analyzed in this study were statistically significant: age, location, symptoms, dental caries, endodontic treatment, delayed eruption, and size. @*Conclusion@#Several criteria can be considered for diagnosis of dentigerous cysts or radicular cysts. Age, location, presence of symptoms and dental caries, previous endodontic treatment, cystic size, and delayed eruption of impacted permanent teeth are reliable factors that should be considered when diagnosing dentigerous and radicular cysts.

Cemento-osseous dysplasia: clinical presentation and symptoms

Objectives@#The purpose of this study was to evaluate risk factors and symptoms in cemento-osseous dysplasia (COD) patients. @*Materials and Methods@#In this study, 62 patients who were diagnosed histologically with COD were investigated from 2010 to 2020 at the author’s institution. We compared clinical and radiological characteristics of symptomatic and asymptomatic patients. The factors were sex, age, lesion size, site, radiologic stage of lesion, apical involvement, sign of infection, and history of tooth extraction. Statistical analysis was performed using Fisher’s exact test and the chi-square test. @*Results@#COD was more prevalent in female patients. With the exception of three cases, all were focal COD. The majority of patients presented with symptoms when the lesion was smaller than 1.5 cm in size. Symptoms were observed when the apex of the tooth was included in the lesion or there was a local infection around the lesion. The history of tooth extraction and previous endodontic treatment were evaluated, and history was not a significant predictor for the onset of symptoms. @*Conclusion@#In this study, risk factors associated with symptomatic patients were size of lesion, apical involvement, and local infection.

Comparative study of bone regeneration using fibrin sealant with xenograft in rabbit sinus: pilot study / 대한악안면성형재건외과학회지

Background@#Stability of the grafted bone volume is one of the important factors to the success of alveolar bone grafts. For this, platelet-rich plasma (PRP) or fibrin sealant is mixed with the bone graft material. Bio-Oss® is a protein-free bovine mineral commonly used in bone graft procedures. The grafting particles are commonly combined with a standard fibrin sealant (Tisseel® ) to fabricate a plastic implantable product. The purpose of this experiment was to evaluate the efficacy of fibrin sealant (Tisseel® ) in bone regeneration performance in a rabbit maxillary sinus model. @*Methods@#A total of five 3.5 kg weight New Zealand white rabbits were used for the study. After elevating the sinus membrane in both maxillary sinus cavities, Bio-Oss® mixed with normal saline (group 1) was filled into the right side, and Tisseel® mixed Bio-Oss® (group 2) was inserted into the other side. The bone mineral density and bone volume were analyzed with microscopic computed tomography (micro-CT) and histomorphometric 12 weeks after application. @*Results@#Histologically, new bone formation rate was 14.8%, and grafted bone rate was 70.5% in group 1. In group 2, they were 18.5% and 60.4%, respectively. According to micro-CT analysis, bone mineral density (mg/cm3 , BMD) was 2.5% larger in group 1. @*Conclusions@#The findings from this study suggest that, although the difference in the bone formation between group 1 and group 2 appears to be insignificant, group 2 had an advantage in using smaller amount of bone substances to achieve the reliable bone formation.

Idiopathic bone cavity: clinical and radiological features of 90 retrospective cases and surgical treatment

Objectives@#The purpose of this study was to evaluate the clinical and radiographic characteristics of idiopathic bone cavity (IBC) to determine the effect of surgical intervention on the process of healing. @*Materials and Methods@#All cases diagnosed with IBC during the period of 2011 to 2020 at our Department of Oral and Maxillofacial Surgery were searched. Ninety cases were retrieved. The features evaluated were sex, age, contour of the lesion, number of teeth involved, site, history of trauma, and postoperative healing pattern. The significance of differences was assessed by Mann–Whitney U test and chi-square test. @*Results@#The female:male ratio showed no predilection toward either sex (0.9:0.8). The mean age of the collected sample was 22.05±14.38 years, and the age ranged from 10 to 58 years. All cases presented in the mandible and showed well-circumscribed radiolucency. Margins were either scalloped or round in shape, and the size varied from one tooth to six teeth involvement. Seventy cases involved three or fewer roots. Three cases showed bilateral lesion. Four cases had a history of trauma at the area of the lesion. Fifty-one cases were followed for six months after surgery, and all showed increased bone density at the lesion. @*Conclusion@#There is no definitive radiological or clinical feature of IBC. Considering the diversity of clinical and radiological features, such a diagnosis relies primarily on surgical findings of an empty bone cavity with no epithelial lining. Our data suggest that surgical intervention be the first choice of treatment as opposed to observation.

Inhibition of cell growth and induction of apoptosis by acacetin in FaDu human pharyngeal carcinoma cells

Acacetin, which is present in damiana (Turnera diffusa) and black locust (Robinia pseudoacacia), has several pharmacologic activities such as antioxidant, anti-inflammatory, and anti-proliferative effects on cancer cells. However, the effect of acacetin on head and neck cancers has not been clearly established. This study aimed to examine the effects of acacetin on cell growth and apoptosis induction in FaDu human pharyngeal carcinoma cells. These were investigated by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay, Live/Dead cell assay, 4′,6-diamidino-2-phenylindole dihydrochloride staining, caspase-3 and caspase-7 activation assay, and immunoblotting in FaDu cells. Acacetin induced FaDu cell death in a dose-dependent manner, with an estimated IC50 value of 41.9 µM, without affecting the viability of L-929 mouse fibroblasts as normal cells. Acacetin treatment resulted in nuclear condensation in the FaDu cells. It promoted the proteolytic cleavage of procaspase-3, -7, -8, and -9 with increasing amounts of the cleaved caspase isoforms in FaDu cells. Acacetin-induced apoptosis in FaDu cells was mediated by the expression of Fas and activation of caspase-8, caspase-3, and poly (ADP-ribose) polymerase. Immunoblotting showed downregulation of the anti-apoptotic mitochondrial proteins Bcl-2 and Bcl-xL, but upregulation of the mitochondria-dependent pro-apoptotic proteins Bax and Badin FaDu cells after acacetin treatment. These findings indicate that acacetin inhibits cell proliferation and induces apoptotic cell death in FaDu human pharyngeal carcinoma cells via both the death receptor-mediated extrinsic apoptotic pathway and the mitochondria-mediated intrinsic apoptotic pathway.

Effect of Resveratrol on Cell Differentiation and Mineralization in Cultured Odontoblasts

Resveratrol (3,4′,5,-trihydroxystilbene), a phytoalexin present in grapes, exerts a variety of actions to reduce superoxides, prevents diabetes mellitus, and inhibits inflammation. Resveratrol acts as a chemo-preventive agent and induces apoptotic cell death in various cancer cells. However, the role of resveratrol in odontoblastic cell differentiation is unclear. In this study, the effect of resveratrol on regulating odontoblast differentiation was examined in MDPC-23 mouse odontoblastic cells derived from mouse dental papilla cells. Resveratrol significantly accelerated mineralization as compared with the control culture in differentiation of MDPC-23 cells. Resveratrol significantly increased expression of ALP mRNA as compared with the control in differentiation of MDPC-23 cells. Resveratrol significantly accelerated expression of ColImRNA as compared with the control in differentiation of MDPC-23 cells. Resveratrol significantly increased expressions of DSPP and DMP-1 mRNAs as compared with the control in differentiation of MDPC-23 cells. Treatment of resveratrol did not significantly affect cell proliferation in MDPC-23 cells. Results suggest resveratrol facilitates odontoblast differentiation and mineralization in differentiation of MDPC-23 cells, and may have potential properties for development and clinical application of dentin regeneration materials.

Combined effect of recombinant human bone morphogenetic protein-2 and low level laser irradiation on bisphosphonate-treated osteoblasts

OBJECTIVES: The purpose of this study was to evaluate the synergic effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) and low-level laser therapy (LLLT) on bisphosphonate-treated osteoblasts. MATERIALS AND METHODS: Human fetal osteoblast cells (hFOB 1.19) were cultured with 100 µM alendronate. Low-level Ga-Al-As laser alone or with 100 ng/mL rhBMP-2 was then applied. Cell viability was measured with MTT assay. The expression levels of receptor activator of nuclear factor kappa-B ligand (RANKL), macrophage colony-stimulating factor (M-CSF), and osteoprotegerin (OPG) were analyzed for osteoblastic activity inducing osteoclastic activity. Collagen type and transforming growth factor beta-1 were also evaluated for bone matrix formation. RESULTS: The results showed that rhBMP-2 and LLLT had a synergic effect on alendronate-treated osteoblasts for enhancing osteoblastic activity and bone matrix formation. Between rhBMP-2 and LLLT, rhBMP-2 exhibited a greater effect, but did not show a significant difference. CONCLUSION: rhBMP-2 and LLLT have synergic effects on bisphosphonate-treated osteoblasts through enhancement of osteoblastic activity and bone formation activity.

A retrospective analysis of risk factors of oromaxillofacial infection in patients presenting to a hospital emergency ward / 대한악안면성형재건외과학회지

BACKGROUND@#The purpose of this study was to review the clinical features of oromaxillofacial infections in patients presenting to a hospital emergency ward, to identify the key factors affecting the requirement for hospitalization, and the potential risk factors predisposing to a prolonged length of hospital stay.@*METHODS@#A retrospective medical record review of the 598 patients treated for oromaxillofacial infection from 2013 to 2017 at the oral and maxillofacial surgery department, Yangsan Pusan National University Hospital, was conducted. The following information was collected from each patient: sex, age, past medical history, site of infection, etiology, admission or outpatient care, level of C-reactive protein (mg/dL), fascial spaces involved, treatment method, and duration of hospitalization. Chi-squared tests were used to identify risk factors, which were further analyzed using multivariable logistic regression.@*RESULTS@#A total of 606 patients were eligible for inclusion in the study, of which eight were excluded due to having incomplete charts; thus, 598 patients were included: 55% were male, mean patient age was 47.1 ± 19.9 years, and 12.9% of patients were diabetic. Furthermore, 71.2% of patients had infection originating in the mandible; the most common tooth of origin was lower posterior, and 29.8% of patients were hospitalized. Risk factors for hospital admission were elderly patients with concurrent disease, elevated C-reactive protein level, and multiple-space infection in the oromaxillofacial area. The duration of hospitalization was correlated with both diabetes and age.@*CONCLUSIONS@#The requirement for hospital admission is determined by the severity of the infection; even severe infections, once treated with appropriate surgery, have no relation to the length of hospital stay. The important risk factors for increased duration of hospitalization are diabetes mellitus and older age. The understanding of risk factors associated with a prolonged hospital stay during the treatment of oromaxillofacial infection will aid in treatment planning as well as highlight the importance of adequate diabetes control in patients at risk of such infection.

The rate and stability of mandibular block bone graft in recent 5 years / 대한악안면성형재건외과학회지

BACKGROUND: The purposes of the present study were to compare implant stabilities of mandibular block bone graft and bovine bone graft and to evaluate influencing factors for implant stability in mandibular block bone (MBB) graft. METHODS: This retrospective study investigated 1224 cases and 389 patients treated by one surgeon in the Department of Oral and Maxillofacial Surgery of Pusan National University Dental Hospital (Yangsan, Korea) between January 2010 and December 2014. Proportions that MBB graft cases constitute in all implant restoration cases and in all bone graft cases were measured. Implant stability quotient (ISQ) values were achieved by the same surgeon before loading. The average ISQ values of the experimental groups were compared. In addition, ISQ values of influencing factors, such as age, sex, implant size, and implant placement site, were compared within the MBB group using OsstellTM Mentor (Osstell®, Göteborg, Sweden). Paired t test and ANOVA were conducted for statistical analysis with a significance level of 0.05. RESULTS: Fifty-five percent of all implant restoration cases performed bone graft while MBB cases constituted 34% of all implant restoration cases and 61% of all bone graft cases. Comparing ISQ values according to bone graft materials, the MBB group manifested sufficient implant stability by presenting comparable ISQ value to that of the experimental group without bone graft. Among the reviewed factors, females, mandibular molar regions, and implants in larger diameter displayed greater implant stabilities. CONCLUSIONS: Satisfactory implant stability was accomplished upon administration of MBB graft. Within the limitation of this study, gender, implant site, and implant diameter were speculated to influence on implant stability in MBB graft.

Relationship between disease stage and renal function in bisphosphonate-related osteonecrosis of the jaw

OBJECTIVES: Bisphosphonate is the primary cause of bisphosphonate-related osteonecrosis of the jaw (BRONJ). Bisphosphonates are eliminated from the human body by the kidneys. It is anticipated that bisphosphonate levels in the body will increase if the kidney is in a weak state or if there is systemic disease that affects kidney function. The aim of this study was to analyze the relevance of renal function in the severity of BRONJ. MATERIALS AND METHODS: Ninety-three patients diagnosed with BRONJ in Pusan National University Dental Hospital from January 2012 to December 2014 were included in this study. All patients underwent a clinical exam, radiographs, and serologic lab test, including urine analysis. The patient's medical history was also taken, including the type of bisphosphonate drug, the duration of administration and drug holiday, route of administration, and other systemic diseases. In accordance with the guidelines of the 2009 position paper of American Association of Oral and Maxillofacial Surgeons, the BRONJ stage was divided into 4 groups, from stage 0 to 3, according to the severity of disease. IBM SPSS Statistics version 21.0 (IBM Co., USA) was used to perform regression analysis with a 0.05% significance level. RESULTS: BRONJ stage and renal factor (estimated glomerular filtration rate) showed a moderate statistically significant correlation. In the group with higher BRONJ stage, the creatinine level was higher, but the increase was not statistically significant. Other factors showed no significant correlation with BRONJ stage. There was a high statistically significant correlation between BRONJ stage and ‘responder group’ and ‘non-responder group,’ but there was no significant difference with the ‘worsened group.’ In addition, the age of the patients was a relative factor with BRONJ stage. CONCLUSION: With older age and lower renal function, BRONJ is more severe, and there may be a decrease in patient response to treatment.

Full Arch Restoration through Orthognathic Surgery after Implantation on the Patients with Mandibular Prognathism and Loss of Posterior Teeth: A Case Report

In case of loss of many teeth due to dental caries or periodontal disease, improvement of masticatory function and aesthetics can be obtained through implant treatment. However, if the patient does not have a normal intercondylar relationship, it is difficult to achieve an ideal occlusal relationship with only prosthetic treatment. In particular, oral reconstruction with orthodontic treatment or orthognathic surgery is necessary for patients with mandibular prognathism. However, if the posterior occlusion collapses due to severe caries or periodontal disease, orthognathic surgery may be difficult. The occlusal vertical stop is very important for the stability of the mandibular position during occlusal reconstruction through orthognathic surgery. The patient in this case had posterior occlusion collapsed due to the caries of a large number of posterior teeth, and showed mandibular prognathism and long face. We planned a full arch restoration with orthognathic surgery and extracted the hopeless teeth. To secure the vertical stop required for orthognathic surgery, the implant was placed before surgery. After the orthognathic surgery and the final prosthesis application, the results were satisfactory for the improvement of the aesthetics and the restoration of the masticatory function.

Corrigendum: Relationship between disease stage and renal function in bisphosphonate-related osteonecrosis of the jaw

This correction is being published to correct the approval number of the Institutional Review Board in this article.

Chitin-fibroin-hydroxyapatite membrane for guided bone regeneration: micro-computed tomography evaluation in a rat model / 대한악안면성형재건외과학회지

BACKGROUND: In guided bone regeneration (GBR) technique, many materials have been used for improving biological effectiveness by adding on membranes. The new membrane which was constructed with chitin-fibroin-hydroxyapatite (CNF/HAP) was compared with a collagen membrane (Bio-Gide®) by means of micro-computed tomography. METHODS: Fifty-four rats were used in this study. A critical-sized (8 mm) bony defect was created in the calvaria with a trephine bur. The CNF/HAP membrane was prepared by thermally induced phase separation. In the experimental group (n = 18), the CNF/HAP membrane was used to cover the bony defect, and in the control group (n = 18), a resorbable collagen membrane (Bio-Gide®) was used. In the negative control group (n = 18), no membrane was used. In each group, six animals were euthanized at 2, 4, and 8 weeks after surgery. The specimens were analyzed using micro-CT. RESULTS: Bone volume (BV) and bone mineral density (BMD) of the new bone showed significant difference between the negative control group and membrane groups (P < 0.05). However, between two membranes, the difference was not significant. CONCLUSIONS: The CNF/HAP membrane has significant effect on the new bone formation and has the potential to be applied for guided bone regeneration.

Effect of low-level laser therapy on bisphosphonate-treated osteoblasts / 대한악안면성형재건외과학회지

BACKGROUND: This study investigates the effect of alendronate-treated osteoblasts, as well as the effect of low-level laser therapy (LLLT) on the alendronate-treated osteoblasts. Bisphosphonate decreases the osteoblastic activity. Various treatment modalities are used to enhance the bisphosphonate-treated osteoblasts; however, there were no cell culture studies conducted using a low-level laser. METHODS: Human fetal osteoblastic (hFOB 1.19) cells were treated with 50 μM alendronate. Then, they were irradiated with a 1.2 J/cm² low-level Ga-Al-As laser (λ = 808 ± 3 nm, 80 mW, and 80 mA; spot size, 1 cm²; NDLux, Seoul, Korea). The cell survivability was measured with the MTT assay. The three cytokines of osteoblasts, receptor activator of nuclear factor κB ligand (RANKL), osteoprotegerin (OPG), and macrophage colony-stimulating factor (M-CSF) were analyzed. RESULTS: In the cells treated with alendronate at concentrations of 50 μM and higher, cell survivability significantly decreased after 48 h (p < 0.05). After the applications of low-level laser on alendronate-treated cells, cell survivability significantly increased at 72 h (p < 0.05). The expressions of OPG, RANKL, and M-CSF have decreased via the alendronate. The RANKL and M-CSF expressions have increased, but the OPG was not significantly affected by the LLLT. CONCLUSIONS: The LLLT does not affect the OPG expression in the hFOB cell line, but it may increase the RANKL and M-CSF expressions, thereby resulting in positive effects on osteoclastogenesis and bone remodeling.

Three-dimensional morphometric analysis of mandibule in coronal plane after bimaxillary rotational surgery / 대한악안면성형재건외과학회지

BACKGROUND: The aim of this report is to present a new reference for aesthetic mandible surgery using three-dimensional cone-beam computed tomography-based treatment planning for orthognathic surgery which can be implemented in surgical planning and perioperative procedure. METHODS: To make an objective standard for evaluating aesthetic mandibular outline, we make an aesthetic scoring criteria with consideration of asymmetry, broad mandibular border line, and prominent mandibular angle. Two maxillofacial surgeons and two orthodontists rated their aesthetical evaluation from 1 to 5. Experimental group consisting of 47 female and 38 male patients who had rotational orthognathic two-jaw surgery from 2010 to 2011 were chosen according to aesthetic scoring done by two maxillofacial surgeons and two orthodontists. A high aesthetic score (≥16) means the facial contour is symmetric, with no broad and narrow aesthetic mandible frontal profiles. Control A group consisted of ten female and ten male patients who had no orthognathic surgery experience and low aesthetic score (≤10). Control B group consisted of ten female and ten male patients who had no orthognathic surgery experience and had anaesthetic mandibular frontal profile and a high aesthetic score (≥16). The three-dimensional image of the patient was taken from dental cone-beam CT (DCT) scanning (experimental group and control A group: 6 months DCT after surgery, control B group: 1st visit DCT). Each DCT was reformatted to reorient the 3D image using 3D analyzing program (OnDemand3D, cybermed Inc, CA, USA). After selection of 12 landmarks and the construction of reoriented horizontal, vertical, and coronal reference lines, 15 measurements were taken in 3D analysis of frontal mandibular morphology. Afterwards, horizontal and vertical linear measurements and angular measurements, linear ratio were obtained. RESULTS: Mean Go’(Rt)-Me’-Go’(Lt) angular measurement was 100.74 ± 2.14 in female patients and 105.37 ± 3.62 in male patients. These showed significant difference with control A group in both genders. Ratio of Go’(Rt),Go’(Lt)-Me’ length to some linear measurements (ratio of Me’-Cd’RtCd’Lt to Me’-Go’(Rt)Go’(Lt), ratio of Me’-Go’ to Me’-Go’(Rt)Go’(Lt), ratio of Go’(Rt)-Go’(Lt) to Me’-Go’(Rt)Go’(Lt)) showed significant difference with control A group in both genders. CONCLUSION: This study was intended to find some standard measurement of mandible frontal view in 3D analysis of aesthetic patient. So, these potential measurement value may be helpful for orthognathic treatment planning to have more aesthetic and perspective outcomes.

Combined effect of bisphosphonate and recombinant human bone morphogenetic protein 2 on bone healing of rat calvarial defects / 대한악안면성형재건외과학회지

PURPOSE: This study aimed to investigate new bone formation using recombinant human bone morphogenetic protein 2 (rhBMP-2) and locally applied bisphosphonate in rat calvarial defects. METHODS: Thirty-six rats were studied. Two circular 5 mm diameter bony defect were formed in the calvaria using a trephine bur. The bony defect were grafted with Bio-Oss(R) only (group 1, n = 9), Bio-Oss(R) wetted with rhBMP-2 (group 2, n = 9), Bio-Oss(R) wetted with rhBMP-2 and 1 mM alendronate (group 3, n = 9) and Bio-Oss(R) wetted with rhBMP-2 and 10 mM alendronate (group 4, n = 9). In each group, three animals were euthanized at 2, 4 and 8 weeks after surgery, respectively. The specimens were then analyzed by histology, histomorphometry and immunohistochemistry analysis. RESULTS: There were significant decrease of bone formation area (p < 0.05) between group 4 and group 2, 3. Group 3 showed increase of new bone formation compared to group 2. In immunohistochemistry, collagen type I and osteoprotegerin (OPG) didn't show any difference. However, receptor activator of nuclear factor kappaB ligand (RANKL) decreased with time dependent except group 4. CONCLUSION: Low concentration bisphosphonate and rhBMP-2 have synergic effect on bone regeneration and this is result from the decreased activity of RANKL of osteoblast.

A clinical study of emergency room visits for oral and maxillofacial lacerations

OBJECTIVES: This study investigated patients with oral and maxillofacial lacerations who visited the emergency room over a three-year period in an effort to determine the optimal treatment for these injuries. MATERIALS AND METHODS: This study examined 1,742 patients with oral and maxillofacial lacerations with 2,014 different laceration locations who visited the emergency room of Pusan National University Hospital (Busan, Korea) over three years, from January 2011 to December 2013. Patients were classified by sex, age, visit day, cause of injury, injury site, and the presence or absence of soft tissue and tooth injuries. RESULTS: The male to female ratio was 2.50:1. Patients under 10 years old were seen most frequently. Most emergency room visits were on weekends. Among intra-oral lacerations, the lip area was the most vulnerable site; among extra-oral lacerations, the chin area was most frequently injured. The most frequent etiology was a slip down. Most lacerations occurred without bone fracture or tooth damage. CONCLUSION: Laceration may differ in large part as compared with the fracture. Therefore, it is necessary to continue collecting data on oral and maxillofacial lacerations to establish optimal emergency room diagnosis and treatment strategies.

Clinical changes of TMD and condyle stability after two jaw surgery with and without preceding TMD treatments in class III patients / 대한악안면성형재건외과학회지

BACKGROUND: This study are to identify the symptomatic changes and condylar stability after 2 jaw surgery without preceding treatments for Temporomandibular joints(TMJ) in class III patients with the TMJ symptoms; and to assess therapeutic effect of 2 jaw surgery and the necessity of preceding treatment for alleviation of TMJ symptoms. METHODS: 30 prognathic patients with preexisting TMJ symptoms were divided into 2 groups according to presence or absence of preceding treatments before the surgery. We evaluated symptomatic changes on both TMJ by questionnaires and clinical examinations. And we reconstructed 3D cone beam computed tomography images before 2 jaw surgery, immediately after the surgery, and 6 months or more after the surgery with SimPlant software, and analyzed the stability of condylar position on 3D reconstruction model. Significances were assessed by the Wilcoxon signed rank test on SPSS ver. 20.0. RESULTS: Both groups had favorable changes of TMJ symptoms after orthognathic surgery. And postoperative position of condyle had good stability during follow-up period. CONCLUSION: 2 jaw surgery without preceding treatments for TMD can have therapeutic effect for TMD patients with class III malocclusion.

Enucleation of large keratocystic odontogenic tumor at mandible via unilateral sagittal split osteotomy: a report of three cases

Keratocystic odontogenic tumor (KCOT) is a common benign tumor of osseous lesions in dental and maxillofacial practice. We describe three cases of large KCOT located in the posterior part of the mandible extending to the angle and ramus region, which were enucleated via sagittal split osteotomy (SSO) of the mandible. There are cases in which a conventional enucleation procedure does not ensure complete excision of the entire lesion without damage to vital structures like the inferior alveolar nerve. In such cases, a SSO approach could be a better choice than conventional methods. The purpose of this article is to describe our experience using unilateral mandibular SSO for removal of a KCOT from the mandible.

Miniscrews versus surgical archwires for intermaxillary fixation in adults after orthognathic surgery / 대한치과교정학회지

OBJECTIVE: We compared the skeletal and dental changes that resulted from the use of two methods of intermaxillary fixation (IMF)-miniscrews and surgical archwire-in 74 adult patients who had Class III malocclusion and were treated with the same orthognathic surgical procedure at a hospital in Korea. METHODS: All the patients underwent Le Fort I osteotomy and bilateral sagittal split ramus osteotomy with rigid fixation. They were divided into two groups according to the type of IMF used-group 1 underwent surgical archwire fixation and group 2 underwent orthodontic miniscrew fixation. In a series of cephalograms for each patient, we compared vertical and horizontal tooth-position measurements: (a) immediately after surgery (T0), (b) 3 months after surgery (T1), and (c) 6 months after surgery (T2). Cephalometric changes within each group were examined using one-way analysis of variance (ANOVA) while the independent samples t-test procedure was used to compare the two groups. RESULTS: After surgery, the maxillary incisors tended to be proclined in both groups although there were no significant differences. Incisor overbite increased significantly in both groups from T0 to T1, and the miniscrew group (group 2) showed slightly greater overbite than the archwire group (group 1). CONCLUSIONS: This study suggest that the use of orthodontic miniscrews and orthodontic surgical archwire for IMF in adult patients results in similar skeletal and dental changes.