Clinical Practice Guidelines for Oropharyngeal Dysphagia / 대한연하장애학회지

Objective@#Dysphagia is a common clinical condition characterized by difficulty in swallowing. It is sub-classified into oropharyngeal dysphagia, which refers to problems in the mouth and pharynx, and esophageal dysphagia, which refers to problems in the esophageal body and esophagogastric junction. Dysphagia can have a significant negative impact one’s physical health and quality of life as its severity increases. Therefore, proper assessment and management of dysphagia are critical for improving swallowing function and preventing complications. Thus a guideline was developed to provide evidence-based recommendations for assessment and management in patients with dysphagia. @*Methods@#Nineteen key questions on dysphagia were developed. These questions dealt with various aspects of problems related to dysphagia, including assessment, management, and complications. A literature search for relevant articles was conducted using Pubmed, Embase, the Cochrane Library, and one domestic database of KoreaMed, until April 2021. The level of evidence and recommendation grade were established according to the Grading of Recommendation Assessment, Development and Evaluation methodology. @*Results@#Early screening and assessment of videofluoroscopic swallowing were recommended for assessing the presence of dysphagia. Therapeutic methods, such as tongue and pharyngeal muscle strengthening exercises and neuromuscular electrical stimulation with swallowing therapy, were effective in improving swallowing function and quality of life in patients with dysphagia. Nutritional intervention and an oral care program were also recommended. @*Conclusion@#This guideline presents recommendations for the assessment and management of patients with oropharyngeal dysphagia, including rehabilitative strategies.

Bone remodeling of the fibula segment as a form of neocondyle after free vascularized bone transfer: a report of two cases

The temporomandibular joint is a unique structure composed of the joint capsule, articular disc, mandibular condyles, glenoid fossa of the temporal bone, surrounding ligaments, and associated muscles. The condyle is one of the major components of a functional temporomandibular joint. Reconstruction of large mandibular defects involving the condyle is a surgical challenge for oral and maxillofacial surgeons. To restore large mandibular defects, there are different options for free flap method such as fibula, scapula, and iliac crest. Currently, the vascularized fibula free flap is the gold standard for reconstruction of complex mandibular defects involving the condyle. In the present report, neocondyle regeneration after mandible reconstruction including the condyle head with fibula free flap was evaluated. In this report, two patients were evaluated periodically, and remodeling of the distal end of the free fibula was observed in both cases after condylectomy or mandibulectomy. With preservation of the articular disc, trapezoidal shaping of the neocondyle, and elastic guidance of occlusion, neocondyle bone regeneration occured without ankylosis. Preservation of the articular disc and maintenance of proper occlusion are critical factors in regeneration of the neocondyle after mandible reconstruction.

The comprehensive on-demand 3D bio-printing for composite reconstruction of mandibular defects / 대한악안면성형재건외과학회지

Background@#The mandible is a functional bio-organ that supports facial structures and helps mastication and speaking. Large mandible defects, generally greater than 6-cm segment loss, may require composite tissue reconstruction such as osteocutaneous-vascularized free flap which has a limitation of additional surgery and a functional morbidity at the donor site. A 3D bio-printing technology is recently developed to overcome the limitation in the composite reconstruction of the mandible using osteocutaneous-vascularized free flap.ReviewScaffold, cells, and bioactive molecules are essential for a 3D bio-printing. For mandibular reconstruction, materials in a 3D bio-printing require mechanical strength, resilience, and biocompatibility. Recently, an integrated tissue and organ printing system with multiple cartridges are designed and it is capable of printing polymers to reinforce the printed structure, such as hydrogel. @*Conclusion@#For successful composite tissue reconstruction of the mandible, biologic considerations and components should be presented with a comprehensive on-demand online platform model of customized approaches.

Correction of malocclusion using sliding fibula osteotomy with sagittal split ramus osteotomy after mandible reconstruction / 대한악안면성형재건외과학회지

Background@#Fibula free flap mandible reconstruction is the standard procedure after wide resection of the mandible. Establishment and maintenance of normal occlusion are important in mandible reconstruction both intraoperatively and after surgery. However, scar formation on the surgical site can cause severe fibrosis and atrophy of soft tissue in the head and neck region.Case presentationHere, we report a case of severe soft tissue atrophy that appeared along with scar formation after mandibular reconstruction through the fibular free flap procedure. This led to normal occlusion collapse after it was established, and the midline of the mandible became severely deviated to the affected side that was replaced with the fibula free flap, leading to facial asymmetry. We corrected the malocclusion with a secondary operation: a sagittal split ramus osteotomy on the unaffected side and a sliding osteotomy on the previous fibula graft. After a healing time of 3 months, implants were placed on the fibula graft for additional occlusal stability. @*Conclusion@#We report satisfactory results from the correction of malocclusion after fibula reconstruction using sliding fibula osteotomy and sagittal split ramus osteotomy. The midline of the mandible returned to its original position and the degree of facial asymmetry was reduced. The implants reduced difficulties that the patient experienced with masticatory function.

Correction of malocclusion using sliding fibula osteotomy with sagittal split ramus osteotomy after mandible reconstruction / 대한악안면성형재건외과학회지

Background@#Fibula free flap mandible reconstruction is the standard procedure after wide resection of the mandible. Establishment and maintenance of normal occlusion are important in mandible reconstruction both intraoperatively and after surgery. However, scar formation on the surgical site can cause severe fibrosis and atrophy of soft tissue in the head and neck region.Case presentationHere, we report a case of severe soft tissue atrophy that appeared along with scar formation after mandibular reconstruction through the fibular free flap procedure. This led to normal occlusion collapse after it was established, and the midline of the mandible became severely deviated to the affected side that was replaced with the fibula free flap, leading to facial asymmetry. We corrected the malocclusion with a secondary operation: a sagittal split ramus osteotomy on the unaffected side and a sliding osteotomy on the previous fibula graft. After a healing time of 3 months, implants were placed on the fibula graft for additional occlusal stability. @*Conclusion@#We report satisfactory results from the correction of malocclusion after fibula reconstruction using sliding fibula osteotomy and sagittal split ramus osteotomy. The midline of the mandible returned to its original position and the degree of facial asymmetry was reduced. The implants reduced difficulties that the patient experienced with masticatory function.

Predicting Vascularized Bone Graft Viability Using 1-Week Postoperative Bone SPECT/CT After Maxillofacial Reconstructive Surgery / 대한핵의학회잡지

Purpose@#We aimed to evaluate the performance of hybrid bone single-photon emission computed tomography (SPECT)/computed tomography (CT) in predicting bone graft viability after maxillary or mandibular reconstructive surgery with vascularized bone grafts. @*Methods@#We retrospectively reviewed 46 bone planar scintigraphy and SPECT/CT images of 45 adult patients taken at 1 week (5–8 days) after maxillary or mandibular reconstructive surgery with vascularized bone grafts. By visual analysis, two nuclear medicine physicians scored the uptake degrees of each bone graft segment compared with the calvarium uptake on planar bone scintigraphy and SPECT/CT, respectively (0 = absence of uptake, 1 = less uptake, 2 = similar uptake, and 3 = more uptake). The imaging results were compared with clinical follow-up for assessing bone graft viability. @*Results@#During follow-up, five bone graft segments were surgically removed and confirmed as nonviable—one had a score of 0, although the other four had a score of 1–3 on planar bone scintigraphy. All five bone graft segments were scored 0 on SPECT/CT and eventually confirmed as nonviable. All other graft segments with a score of > 1 on SPECT/CT were viable and uneventful.The anatomical CT information on SPECT/CT images was helpful in discriminating bone graft uptake from adjacent bone or soft tissue uptake. @*Conclusions@#The absence of tracer uptake by the vascularized bone graft on bone SPECT/CT at 1 week after maxillary or mandibular reconstructive surgery can predict graft failure. Bone SPECT/CT can be used to predict vascularized bone graft viability postoperatively.

Immune regulation by protein ubiquitination: roles of the E3 ligases VHL and Itch

Protein ubiquitination is an important means of post-translational modification which plays an essential role in the regulation of various aspects of leukocyte development and function. The specificity of ubiquitin tagging to a protein substrate is determined by E3 ubiquitin ligases via defined E3-substrate interactions. In this review, we will focus on two E3 ligases, VHL and Itch, to discuss the latest progress in understanding their roles in the differentiation and function of CD4 T helper cell subsets, the stability of regulatory T cells, effector function of CD8 T cells, as well as the development and maturation of innate lymphoid cells. The biological implications of these E3 ubiquitin ligases will be highlighted in the context of normal and dysregulated immune responses including the control of homeostasis, inflammation, auto-immune responses and anti-tumor immunity. Further elucidation of the ubiquitin system in immune cells will help in the design of new therapeutic interventions for human immunological diseases and cancer.

Surgical implications of anatomical variation in anterolateral thigh flaps for the reconstruction of oral and maxillofacial soft tissue defects: focus on perforators and pedicles

OBJECTIVES: To gain information on anatomical variation in anterolateral thigh (ALT) flaps in a series of clinical cases, with special focus on perforators and pedicles, for potential use in reconstruction of oral and maxillofacial soft tissue defects. MATERIALS AND METHODS: Eight patients who underwent microvascular reconstructive surgery with ALT free flaps after ablative surgery for oral cancer were included. The number of perforators included in cutaneous flaps, location of perforators (septocutaneous or musculocutaneous), and the course of vascular pedicles were intraoperatively investigated. RESULTS: Four cases with a single perforator and four cases with multiple perforators were included in the ALT flap designed along the line from anterior superior iliac spine to patella. Three cases had perforators running the septum between the vastus lateralis and rectus femoris muscle (septocutaneous type), and five cases had perforators running in the vastus lateralis muscle (musculocutaneous type). Regarding the course of vascular pedicles, five cases were derived from the descending branch of the lateral circumflex femoral artery (type I), and three cases were from the transverse branch (type II). CONCLUSION: Anatomical variation affecting the distribution of perforators and the course of pedicles might prevent use of an ALT free flap in various reconstruction cases. However, these issues can be overcome with an understanding of anatomical variation and meticulous surgical dissection. ALT free flaps are considered reliable options for reconstruction of soft tissue defects of the oral and maxillofacial area.

Unilateral intraoral vertical ramus osteotomy and sagittal split ramus osteotomy for the treatment of asymmetric mandibles

In surgery for facial asymmetry, mandibles can be classified into two types, rotational and translational, according to the required mandibular movements for surgery. During surgery for rotational mandibular asymmetry, a bilateral sagittal split ramus osteotomy (BSSRO) may cause a large bone gap between the proximal and distal segments as well as condylar displacement, resulting in a relapse of the temporomandibular joint disorder, especially in severe cases. The intraoral vertical ramus osteotomy has an advantage, in this respect, because it causes less rotational displacement of the proximal segment on the deviated side and even displaced or rotated condylar segments may return to their original physiologic position. Unilateral intraoral vertical ramus osteotomy (UIVRO) on the short side combined with contralateral SSRO was devised as an alternative technique to resolve the spatial problems caused by conventional SSRO in cases of severe rotational asymmetry. A series of three cases were treated with the previously suggested protocol and the follow-up period was analyzed. In serial cases, UIVRO combined with contralateral SSRO may avoid mediolateral flaring of the bone segments and condylar dislocation, and result in improved condition of the temporomandibular joint. UIVRO combined with contralateral SSRO is expected to be a useful technique for the treatment of rotational mandibular asymmetry.

A survey of the satisfaction of patients who have undergone implant surgery with and without employing a computer-guided implant surgical template

PURPOSE: This study aims to investigate the degree of subjective pain and the satisfaction of patients who have undergone an implant treatment using a computer-guided template. MATERIALS AND METHODS: A survey was conducted for 135 patients who have undergone implant surgery with and without the use of the computer-guided template during the period of 2012 and 2013 in university hospitals, dental hospitals and dental clinics that practiced implant surgery using the computer-guided template. Likert scale and VAS score were used in the survey questions, and the independent t-test and One-Way ANOVA were performed (alpha=.05). RESULTS: The route that the subjects were introduced to the computer-guided implant surgery using a surgical template was mostly advices by dentists, and the most common reason for which they chose to undergo such surgery was that it was accurate and safe. Most of them gave an answer that they were willing to recommend it to others. The patients who have undergone the computer-guided implant surgery felt less pain during the operation and showed higher satisfaction than those who have undergone conventional implant surgery. Among the patients who have undergone computer-guided implant surgery, those who also had prior experience of surgery without a computer-guided template expressed higher satisfaction with the former (P<.05). CONCLUSION: In this study, it could be seen that the patients who have undergone computer-guided implant surgery employing a surgical template felt less pain and had higher satisfaction than those with the conventional one, and the dentist's description could provide the confidence about the safety of surgery.

An assessment of template-guided implant surgery in terms of accuracy and related factors

PURPOSE: Template-guided implant therapy has developed hand-in-hand with computed tomography (CT) to improve the accuracy of implant surgery and future prosthodontic treatment. In our present study, the accuracy and causative factors for computer-assisted implant surgery were assessed to further validate the stable clinical application of this technique. MATERIALS AND METHODS: A total of 102 implants in 48 patients were included in this study. Implant surgery was performed with a stereolithographic template. Pre- and post-operative CTs were used to compare the planned and placed implants. Accuracy and related factors were statistically analyzed with the Spearman correlation method and the linear mixed model. Differences were considered to be statistically significant at P< or =.05. RESULTS: The mean errors of computer-assisted implant surgery were 1.09 mm at the coronal center, 1.56 mm at the apical center, and the axis deviation was 3.80degrees. The coronal and apical errors of the implants were found to be strongly correlated. The errors developed at the coronal center were magnified at the apical center by the fixture length. The case of anterior edentulous area and longer fixtures affected the accuracy of the implant template. CONCLUSION: The control of errors at the coronal center and stabilization of the anterior part of the template are needed for safe implant surgery and future prosthodontic treatment.

Implant Fixture Installation in the Posterior Maxilla Using a Tooth-supported Surgical Template Based on Computer Assisted Treatment Planning

Comparison of Postoperative Stability between Distraction Osteogenesis and Bilateral Sagittal Split Ramus Osteotomy in Mandibular Retrognathism

0.05). Mean follow up periods were 10.77 months for BSSRO group and 11.28 months for DO group, respectively. After mandibular advancement, mean positional changes in the condyle were 0.56+/-1.43 mm horizontally and 0.72+/-1.61 mm vertically for BSSRO group and 0.53+/-1.56 mm horizontally and 0.56+/-1.75 mm vertically for DO group, respectively. Mean change of distance from B point to Y-axis was -1.76+/-0.83 mm for BSSRO group and -2.14+/-1.82 mm for DO group, respectively. According to the condylar position and B point, there were no significant differences in postoperative stability between the two groups (P>0.05).CONCLUSION: There was no significant difference in postoperative stability between DO and BSSRO group according to condylar position and B point. Based on the results of the present study, it is hypothesized that DO would be a good treatment choice for severe mandibular retrognathism because DO could achieve more mandibular advancement and concurrent soft tissue elongation.

Implant Fixture Installation in the Anterior Mandible by Use of a Mucosa Supported Surgical Template Based on Computer Assisted Treatment Planning

The Development of a Giant Extraskeletal Osteochondroma in the Masticatory Space of the Mandible

Implant surgery based on computer simulation surgical stent and the assessment with the image fusion technique

INTRODUCTION: The planning of implant surgery is an important factor for the implant prosthesis. Stereolithographic (SLA) surgical stents based on a computer simulation are quite helpful for clinicians to perform the surgery as planned. Although many clinical and technical trials have been performed for computed tomography (CT)-guided implant stents to improve the surgical procedures and prosthetic treatment, there are still many problems to solve. We developed a system of a surgical guide based on 3 dimensional (3D) CT for implant therapy and achieved satisfactory results in the terms of planning and operation. MATERIALS AND METHODS: Fifteen patients were selected and 30 implant fixtures were installed. The preoperative CT data for surgical planning were prepared after obtaining informed consent. Surgical planning was performed using the simulation program, Ondemend3D In2Guide. The stents were fabricated based on the simulation data containing information of the residual bone, the location of the nerve, and the expected design of the prostheses. After surgery with these customized stents, the accuracy and reproducibility of implant surgery were evaluated based on the computer simulation. The data of postoperative CT were used to confirm this system using the image fusion technique and compare the implant fixtures between the planned and implanted. RESULTS: The mean error was 1.18 (+/-0.73) mm at the occlusal center, 1.23 (+/-0.67) mm at the apical center, and the axis error between the two fixtures was 3.25degrees (+/-3.00). These stents showed superior accuracy in maxilla cases. The lateral side error at the apical center was significantly different from the error at the occlusal center but there were no significant differences between the premolars, 1st molars and 2nd molars. CONCLUSION: SLA surgical stents based on a computer simulation have the satisfactory accuracy and are expected to be useful for accurate planning and surgery if some errors can be improved.

Development and application of stent-based image guided navigation system for oral and maxillofacial surgery / 대한구강악안면방사선학회지

PURPOSE: The purpose of this study was to develop a stent-based image guided surgery system and to apply it to oral and maxillofacial surgeries for anatomically complex sites. MATERIALS AND METHODS: We devised a patient-specific stent for patient-to-image registration and navigation. Threedimensional positions of the reference probe and the tool probe were tracked by an optical camera system and the relative position of the handpiece drill tip to the reference probe was monitored continuously on the monitor of a PC. Using 8 landmarks for measuring accuracy, the spatial discrepancy between CT image coordinate and physical coordinate was calculated for testing the normality. RESULTS: The accuracy over 8 anatomical landmarks showed an overall mean of 0.56+/-0.16 mm. The developed system was applied to a surgery for a vertical alveolar bone augmentation in right mandibular posterior area and possible interior alveolar nerve injury case of an impacted third molar. The developed system provided continuous monitoring of invisible anatomical structures during operation and 3D information for operation sites. The clinical challenge showed sufficient accuracy and availability of anatomically complex operation sites. CONCLUSION: The developed system showed sufficient accuracy and availability in oral and maxillofacial surgeries for anatomically complex sites.

Is Helicobacter Pylori the Pathogen of Chronic Tonsillitis? / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Tonsillar tissue is a component of mucosa-associated lymphoid tissue (MALT), which has evolved to protect vulnerable mucosal surfaces. Helicobacter pylori, implicated as an etiological factor in duodenal ulcer and gastritis, induces the appearance of lymphoid aggregates in the stomach. Therefore, we investigate the possibility that tonsils can be extragastric reservoir and target tissue for H. pylori. SUBJECTS AND METHOD: Campylobacter-Like Organism (CLO) test and immunohistochemical (IHC) analysis for H. pylori was performed on 98 patients undergoing tonsillectomy. Chronic tonsillitis group (62 patients) and controlled group (36 patients) were enrolled in this study. Tissue samples were collected from excised palatine tonsils. Two millimeter diameter tissue piece that had been obtained from palatine tonsil specimens were placed in the CLO test kit. Remnant tonsils were sent to the Department of Pathology for IHC analysis. RESULTS: Using the CLO test, H. pylori was detected in 60 (61.2%) of the 98 patients, 39 (62.9%) of 62 in chronic tonsillitis group and 21 (58.3%) of 36 in control group. Using the IHC analysis, it was detected in 54 (55.1%) of the 98 patients, 35 (56.5%) of 62 in chronic tonsillitis group and 19 (52.8%) of 36 in control group. There are no significant differences between chronic tonsillitis group and control group with regard to both CLO & IHC analysis. CONCLUSION: This result suggests that palatine tonsil represents an extragastric reservoir for H. pylori infection, but not a target tissue.

The three dimensional analysis of volumetric airway change in orthognathic surgery of mandibular prognathism

Early nerve regeneration on the crushing injury model and the autogenous nerve graft model of rat sciatic nerve