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.

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.

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.

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.

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.

Sports-Related Oral and Maxillofacial Injuries: A 5-Year Retrospective Study, Pusan National University Dental Hospital.

PURPOSE: The incidence of sports trauma is gradually increasing, and its importance is therefore also increasing. The present study was conducted to analyze the types, proportions, and tendencies of sports trauma associated with the oral and maxillofacial regions. PATIENTS AND METHODS: Patients who visited the Emergency Department of Pusan National University Dental Hospital between 2014 and 2018 for more than 5 years were surveyed through retrospective epidemiologic investigations. Type of sports was classified according to American Academy of Pediatrics classification. For statistical analysis, age and gender distribution, cause of trauma, and annual trends data were collected. RESULTS: Of the 517 patients, most of the patients were teenagers (27.9%), followed by those younger than 10 years (23.2%) (χ2 = 22.897; P = .002), and noncontact sports, which is cycling, was the most common (43.5%) cause for trauma in both adult and children groups (χ2 = 91.824; P < .001). The most common sports associated with contact sports, limited-contact sports, and noncontact sports were football (47.7%), baseball (50.0%), and cycling (74.8%), respectively. The causes for trauma injury were as follows: contact sports, other person's body (53.4%); limited-contact sports, other objects (60.9%); and noncontact sports, slip down (77.4%) (χ2 = 298.901; P < .001). The prevalence and incidence of sports injuries increase every year, and the proportion of injured patients in May was the highest (χ2 = 52.360; P = .181). The high percentage of traumatic sports demonstrated statistically significant trends (χ2 = 43.073; P = .002). Kickboard injuries showed a rapid increase recently (P for linear trend = .045), whereas other sports showed no significant trends. CONCLUSIONS: Considering the increasing incidence of sports-related injuries, oral and maxillofacial surgeons should be more concerned with maxillofacial trauma during sports.

Importance in the occurrence rate of shortest buccal bone marrow distance (<1 mm) for sagittal split ramus osteotomy.

BACKGROUND/PURPOSE: The neurosensory disturbance is a common complication following sagittal split ramus osteotomy (SSRO) whereas the shortest buccal bone marrow (SBM) is an important risk factor. The present study aimed to investigate the relationship between the occurrence rates of SBM among three skeletal patterns. METHODS: The cone-beam computed tomography (CBCT) images of 90 participants were divided into skeletal Class I, II, and III. There were six horizontal planes separated apart by a 2 mm interval; it started with plane 0 (original intact mandibular canal) to plane 5 which was 10 mm below. The data of SBM were divided into two groups (SBM ≥ 1 mm and SBM < 1 mm). With an SBM value < 1 mm, we defined a high occurrence rate of postoperative neurosensory abnormality or unfavorable split. RESULTS: The Class III patients had the smallest SBM value (1.31-1.75 mm) whereas the Class II patients had the largest SBM value (1.57-2.09 mm). For the Class III patients, the highest and lowest occurrence rates of SBM were 56.5% and 43.5% respectively. For the Class II patients, the highest and lowest occurrence rates of SBM were 37.1% and 17.7% respectively. The patients with Class III malocclusion had higher occurrence rates of SBM than the patients with Class II malocclusion. CONCLUSION: Class III had a significantly higher occurrence of probability (SBM < 1 mm) than Class II. Therefore, patients with Class III were more likely to experience postoperative neurosensory abnormalities and unfavorable split than patients with Class II.

Non-thermal plasma accelerates the healing process of peripheral nerve crush injury in rats.

The objective of this study was to evaluate the effect of non-thermal plasma (NTP) on the healing process of peripheral nerve crush injuries, which can occur during dental implant procedures. For this, a rat model of sciatic nerve crush injury (SNCI) was adopted. The rats were divided into three groups: non-nerve damage (non-ND), nerve damage (ND), and ND+NTP group. To evaluate the sciatic nerve (SN) function, the static sciatic index was calculated, and the muscle and SN tissues were subjected to a histologic analysis. The results showed that NTP effectively accelerated the healing process of SNCI in rats. In contrast to the ND group, which showed approximately 60% recovery in the SN function, the NTP-treated rats showed complete recovery. Histologically, the NTP treatments not only accelerated the muscle healing, but also reduced the edema-like phenotype of the damaged SN tissues. In the ND group, the SN tissues had an accumulation of CD68-positive macrophages, partially destroyed axonal fibers and myelinated Schwann cells. Conversely, in the ND+NTP group, the macrophage accumulation was reduced and an overall regeneration of the damaged axon fibers and the myelin sheath was accomplished. The results of this study indicate that NTP can be used for healing of injured peripheral nerves.

The Effect of Buccal Fat Pad Graft in the Palatoplasty and the Risk Factor of Postoperative Palatal Fistula.

PURPOSE: The aim of this study was to evaluate the effect of buccal fat pad (BFP) in the palatoplasty and to investigate the risk factors associated with postoperative palatal fistula formation. MATERIALS AND METHODS: Sixty-five cleft palate patients were enrolled for this study. Clinical data regarding sex, age, type of cleft, surgical technique, the ratio of cleft width, and BFP graft were collected. The ratio of cleft width was measured and calculated using preoperative clinical photographs. In 36 patients, the BFP was harvested and grafted on the cleft palate to prevent palatal fistula formation. The patients were followed up, the incidence of fistula formation was investigated, and the risk factors related with the fistula were evaluated. RESULTS: Four patients had postoperative palatal fistula and were not BFP grafted during operation. The BFP graft and ratio of cleft width are significant factors in palatal fistula formation (P = .035, .003). There was a significant difference in the ratio of cleft width between the normal and fistula groups (P = .006). In the logistic regression analysis, there was significant association between high ratio of cleft width and palatal fistula formation in the no BFP group (odds ratio; 11.15, P = .036). CONCLUSIONS: The ratio of cleft width and BFP graft was a significant factor in palatal fistula formation. The BFP graft is a reliable procedure to prevent palatal fistula formation and increase the success of palatoplasty.

Complications Following Orthognathic Surgery for Patients With Cleft Lip/Palate.

INTRODUCTION: Cleft lip/palate is a facial anomaly caused by an abnormal developmental process. It is also the most common congenital anomaly. Orthognathic surgery is required in 25% of patients with cleft lip and palate for the correction of dentofacial deformity. There are various complications that can occur after orthognathic surgery. Complications that can occur during surgery include bleeding, improper fracture, and injuries to the inferior alveolar nerve (IAN) and lingual nerve. Meanwhile, postoperative complications include hemorrhage, edema, pain, infection, and delayed union or nonunion. This study retrospectively examines the complications that occurred after the orthognathic surgery in cleft lip/palate patients at Pusan National University Dental Hospital. PATIENTS AND METHODS: From June 1, 2008 to July 31, 2017, we selected 17 patients who underwent orthognathic surgery for cleft lip/palate at the Department of Oral and Maxillofacial Surgery, Pusan National University Dental Hospital. The patients were treated at different hospitals for all operations related to cleft lip/palate. RESULT: Intraoperative complications include hemorrhage, inadequate fracture, injury to the IAN and lingual nerve, root damage, and fistula. The patients who were evaluated included 2 patients with inadequate fracture, 3 patients with injury to the IAN, and 1 patient with fistula. Postoperative complications (e.g., as damage of the inferior alveolar nerve and velopharyngeal insufficiency) may occur, and all patients recovered during the follow-up period of 6 months or more after the surgery. The relapse rates were A-N per 14.0%, Pog-N per 15.1%, SNA 24.4%, and SNB 4.6%. There was no statistically significant difference in relapse rate. CONCLUSION: Complications that may occur after the orthognathic surgery in the patients with cleft lip/palate are similar to those without cleft lip/palate.

Zoledronate Enhances Osteocyte-Mediated Osteoclast Differentiation by IL-6/RANKL Axis.

Bisphosphonates are one of the most widely used synthetic pyrophosphate analogues for the treatment of bone resorbing diseases such as osteoporosis, multiple myeloma, and bone metastases. Although the therapeutic usefulness of bisphosphonates mainly depends on their anti-osteoclastogenic effect, a severe side-effect of bisphosphonates called bisphosphonate-related osteonecrosis of the jaw (BRONJ) could not be explained by the anti-osteoclastogenic effect of bisphosphonates. In the present study, we have evaluated the changes in osteoclastogenesis- or osteoblastogenesis-supporting activities of osteocytes induced by bisphosphonates. Zoledronate, a nitrogen-containing bisphosphonate, markedly increased both the receptor activator of nuclear factor kB ligand (RANKL) as well as sclerostin in osteocyte-like MLO-Y4 cells, which were functionally revalidated by osteoclast/osteoblast generating activities of the conditioned medium obtained from zoledronate-treated MLO-Y4 cells. Of note, the zoledronate treatment-induced upregulation of the RANKL expression was mediated by autocrine interleukin-6 (IL-6) and subsequent activation of the signal transducer and activator of transcription 3 (STAT3) pathway. These results were evidenced by the blunted RANKL expression in the presence of a Janus activated kinase (JAK2)/STAT3 inhibitor, AG490. Also, the osteoclastogenesis-supporting activity was significantly decreased in zoledronate-treated MLO-Y4 cells in the presence of IL-6 neutralizing IgG compared to that of the control IgG. Thus, our results show previously unanticipated effects of anti-bone resorptive bisphosphonate and suggest a potential clinical importance of osteocytes in BRONJ development.

Three-Dimensional Analysis of Perioperative Condylar Displacement After Mandibular Setback Surgery With Intended Manual Condylar Positioning.

PURPOSE: The purpose of this study is to investigate the effect of orthognathic surgery with intended manual condylar positioning on condyle by examining a change in its position. METHOD: About 18 patients with mandibular prognathism who underwent orthognathic surgery with intentional manual condyle positioning were included. Condyle displacement was analyzed through 3D cone-beam computed tomography before and after operation. The patients were categorized into 2 experimental groups: group A (1-jaw) and group B (2-jaw). The experimental groups were examined before surgery (T0), 3 days (T1), and 6 months (T2) after surgery. Condylar displacement direction was investigated in terms of bodily shift and rotational movement. RESULTS: Downward bodily shift of condyle after surgery was significantly apparent from all of the patients. Condylar bodily shift in other directions was statistically insignificant. Gross bodily shift of condyle right after surgery was anterolateral-inferior direction. In perspective of rotational movement, condyle rotated in infero-medial direction right after operation, but no significant change was presented afterwards. In addition, no significant difference in the amounts of condylar shift and pattern existed between groups A and B. CONCLUSION: Intended manual condylar positioning may minimize postoperative displacement of condyle while accomplishing skeletal stability.

Evaluation of Intersegmental Displacement After Mandibular Setback Split Ramus Osteotomy Using Modified L-Shaped Monocortical Plate: Cone-Beam Computed Tomography Superimposition.

PURPOSE: The purpose of the current study is to compare intersegmental displacements after mandibular setback sagittal split ramus osteotomy (SSRO) using 4 types of osteosynthesis methods. PATIENTS AND METHODS: This is a retrospective study of 53 subjects who presented underwent bilateral setback SSRO at Pusan National University Hospital from January 2009 to December 2013. The subjects were divided into 4 groups according to the osteosynthesis method applied: group A-modified L-type monocortical plate; B-conventional miniplate; group C-bicortical screws; group D-metal and absorbable screws. To obtain the intersegmental displacement, the mean of the differences of the 3-dimensional from T0 (2 days after surgery) to T1 (6 months after surgery) was calculated for the right and left condylar heads (condylion, Cd) and the right and left coronoid processes (Cps) using 3-dimensional imaging software (Ondemand 3D; Cybermed Co, Seoul, Korea). RESULTS: For the condylion in the x, y, z coordinate system, in group A, there were significant differences in the y-axis for the right and left Cd; in group B, significant differences in the y-axis for the right Cd and in the y- and z-axes for the left Cd; in group C, no significant differences in the axis for the Cd; and in group D, there were significant differences in the y- and z-axes for the right Cd and in the x- and y-axes for the left Cd. For the Cps, the results are not much different from the condylion movement in all group. CONCLUSION: In the current study, group C manifested the greatest displacement for the healing period. Group A did not show the significant difference to group B. In view of these results, modified L-shaped monocortical plate can be applied for osteosynthesis effectively.

Skeletal stability after maxillary posterior-superior movement for skeletal Class III deformities: pterygoid process fracture versus removal.

PURPOSE: To evaluate maxillary stability after Le Fort I osteotomy using posterosuperior movement after pterygoid process fracture or removal and mandibular setback surgery for skeletal Class III deformities. MATERIALS AND METHODS: A retrospective cohort study was performed of changes in 28 patients with skeletal Class III deformity using 3-dimensional (3D) measurement point coordinates obtained by cone-beam computed tomographic superimposition. The predictor variable was management of the pterygoid process (fracture vs removal). The outcome variables were changes in measurement points based on 3D coordinates obtained preoperatively, immediately postoperatively, and 6 months after surgery. Linear mixed-effects models were applied to evaluate postoperative stability. RESULTS: The 3D cephalometric outcome variables for 14 patients who had undergone pterygoid process fracture were compared with those for 14 patients who had undergone pterygoid process removal. The postoperative nasopalatine canal points moved superiorly 0.11 mm and inferiorly 0.06 mm in the fracture and removal groups, respectively. However, most of the postoperative relapse was within 1 mm. There were no differences in postoperative skeletal changes shown by the fracture and removal groups (P < .05). CONCLUSIONS: The results suggest that surgeons can achieve good skeletal stability in posterosuperior movement from Le Fort I osteotomy, regardless of whether the pterygoid process is fractured or removed.

Effect of occlusal vertical dimension changes on postsurgical skeletal changes in a surgery-first approach for skeletal Class III deformities.

INTRODUCTION: The purposes of this study were to investigate the relationship between occlusal vertical dimension (VD) changes and postsurgical skeletal changes in the surgery-first approach and to derive regression models for the final mandibular setback at B-point. METHODS: This retrospective study included 40 patients (16 men, 24 women; ages, 22.6 ± 4.0 years) who had undergone a bimaxillary surgery-first approach. Using cephalograms generated from cone-beam computed tomography representing the presurgical, postsurgical, and posttreatment stages, skeletal landmarks in the maxilla and mandible were investigated to derive multivariate linear regression-based prediction models. Additionally, a patient classification based on the VD was established and verified to generate regression models for the classified groups. RESULTS: For the nonincreased VD group, the surgical setback of B-point was its predictor for the final mandibular setback (R(2) at 92%). Meanwhile, the final mandibular setback of the increased VD group was predicted according to the surgical upward movement of pogonion, the postsurgical horizontal position of A-point, and the postsurgical vertical position of the coronoid process (R(2) at 94%). CONCLUSIONS: The results of this study support the clinical observation that the more increased the vertical occlusal dimension after surgery, the less predictable the position of B-point at the posttreatment stage.

Sinus irrigation as an adjunctive therapy for odontogenic maxillary sinusitis - an in-depth analysis.

BACKGROUND: Odontogenic maxillary sinusitis (OMS) is widely acknowledged in both the dentistry and otolaryngology fields. Recently, iatrogenic odontogenic maxillary sinusitis cases can be encountered frequently. The purpose of this study was to evaluate the effect of intraoral sinus irrigation using the small lateral window approach in patients with odontogenic maxillary sinusitis by comparing pre- and postoperative volumetric measurement of CBCT and symptoms. We surveyed 21 patients who visited the Oral and Maxillofacial Surgery Department at PNUDH from 2016 to 2022. All the patients' information was extracted from an electronic database. The patients with a follow-up period of 2 months or more were included. The three-dimensional volumetric measurement was performed using the ImageJ program (National Institute of Health, University of Wisconsin). RESULTS: Among 21 patients, 16 (76.1%) were male, and 5 (23%) were female. The most common type of surgery was general anesthesia (16 cases) in which oroantral fistula was present in 7 cases. In the causes of maxillary sinusitis, there were seven implant-related patients, five patients of tooth extraction, seven patients of bone grafting, and two patients in other groups. Radiographic opacity decreased by 40.15% after sinus irrigation especially in bone graft and tooth extraction cases. Clinically, symptoms improved in 17 patients (80.9%). CONCLUSION: By this study, it can be concluded that maxillary sinus irrigation using the small lateral window approach is a clinically and radiologically effective treatment method for odontogenic maxillary sinusitis.

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.