Intra-sinus rigid fixation of a resorbable barrier membrane to repair a large perforation of the sinus membrane: a technical note

A resorbable barrier membrane is commonly used for the repair of perforated sinus membranes during sinus lifting surgeries. However, repairing largescale perforations poses challenges for clinicians as the protection and isolation of graft material remain uncertain. With this technique, we aimed to prevent graft material loss and subsequent sinus-related complications using intra-sinus rigid fixation of the resorbable barrier membrane in cases with a large perforation of the sinus membrane.

The dual-port endoscope-assisted cyst enucleation on the maxillofacial region / 대한악안면성형재건외과학회지

Background@#Endoscope-assisted surgery is a surgical method that has been used in oral and maxillofacial surgical fields. It provides good illumination, clear, and magnified visualization of the operative field. The purpose of this article is to describe the early clinical experiences to conduct minimally invasive surgery with endoscope-assisted enucleation of cysts on the jaw. It appears that this approach may be a superior alternative to the conventional approach. @*Methods@#In this study, 24 patients (9 females, 15 males, average age 41.5) underwent endoscope-assisted cyst enucleation under general anesthesia. All operations were done by one surgeon. The cases were classified depending on whether bone penetration occurred at the cyst site. The cystic lesions were enucleated using an endoscope with a 0°, 1.9 mm diameter, or a 30°, 2.7 mm diameter. Two bony windows were used for the insertion of a syringe for irrigation, curettes, suction tips, sinus blades, surgical drills, and an endoscope. An additional small channel was made for the insertion of endoscopic instruments. @*Results@#The 24 patients who underwent cyst enucleation were regularly observed for 3 to 12 months to evaluate for complications. Although some patients experienced swelling and numbness, these symptoms did not persist, and the patients soon returned to normal and there was no sign of recurrence. @*Conclusions@#The results of this study have suggested the possibility of minimally invasive surgery with endoscopes when it comes to cyst removal in the oral and maxillofacial region. Nevertheless, this study has limitations designed as a preliminary report focusing on the feasibility of endoscope-assisted cyst enucleation in the oral and maxillofacial regions.

The Prevalence of Sjögren's Syndrome in Rheumatoid Arthritis Patients and Their Clinical Features

Background@#To estimate the prevalence of Sjögren's syndrome (SS) in patients with rheumatoid arthritis (RA) and to compare the clinical features of RA patients with and without SS. @*Methods@#We conducted a retrospective study of RA patients who visited a rheumatology clinic in a tertiary referral hospital in Korea between May 20 and July 22, 2016. All patients fulfilled the classification criteria for RA, and the diagnosis of SS was made clinically by rheumatologists and according to the 2002 American-European Consensus Group (AECG), 2012 American College of Rheumatology (ACR), and 2016 ACR/European League Against Rheumatism (EULAR) classification criteria. The prevalence was estimated as the number of SS patients within the total number of RA patients. The disease activity and treatment pattern of RA were compared between patients with and without SS. @*Results@#Among 827 RA patients, 72 patients (8.7%) were diagnosed with SS by a rheumatologist, though only 60 patients (7.3%) satisfied the 2002 AECG classification criteria for SS. Fifty-two patients (6.3%) and 56 patients (6.8%) fulfilled the 2012 ACR and 2016 ACR/EULAR classification criteria, respectively. The prevalence of SS in RA patients was 10.5%, 17.0%, and 67.6% in rheumatoid factor, antinuclear antibody (≥ 1:80), and anti-Ro antibody positive patients, respectively. @*Conclusion@#The prevalence of SS among RA patients was 8.7% according to rheumatologists' diagnosis. The presence of SS did not affect the treatment patterns of RA patients. However, the autoantibody profiles and demographics of RA patients with SS differed from those of patients without SS.

Autoantibody-Mediated Dysfunction of Salivary Glands Leads to Xerostomia in SKG Mice

Sjögren's syndrome (SS) is a chronic heterogeneous disease that mainly affects exocrine glands, leading to sicca syndromes such as xerostomia. Despite the second highest prevalence rate among systemic autoimmune diseases, its pathophysiology remains largely unknown. Here we report that SKG mice, a cardinal model of Th17 cell-mediated arthritis, also develop a secondary form of SS-like disorder upon systemic exposure to purified curdlan, a type of β-glucan. The reduced production of saliva was not caused by focal immune cell infiltrates but was associated with IgG deposits in salivary glands. Sera from curdlan-injected SKG mice contained elevated titers of IgG (predominantly IgG1), autoantibody to the muscarinic type 3 receptor (M3R) and inhibited carbachol-induced Ca2+ signaling in salivary acinar cells. These results suggest that the Th17 cells that are elicited in SKG mice promote the production of salivary gland-specific autoantibodies including anti-M3R IgG; the antibodies are then deposited on acinar cells and inhibit M3R-mediated signaling required for salivation, finally leading to hypofunction of the salivary glands. This type II hypersensitivity reaction may explain the origin of secondary SS occurring without focal leukocyte infiltrates.

Local anesthesia for mandibular third molar extraction

Mandibular third molar extraction is commonly performed in dental clinics. However, the optimal method of anesthesia has not been established for this procedure. The conventional inferior alveolar nerve block is the most widely used method. However, its success rate is not high and it may lead to complications, such as aspiration and nerve injury. Therefore, various anesthesia methods are being investigated. Articaine has been proven to be efficacious in a number of studies and is being used with increasing frequency in clinical practice. In this review article, we will briefly review various local anesthesia techniques, anesthetics, and a computer-controlled local anesthetic delivery (CCLAD) system, which reduces pain by controlling the speed of drug injection, for mandibular third molar extraction.

Multiple brain abscesses treated by extraction of the maxillary molars with chronic apical lesion to remove the source of infection / 대한악안면성형재건외과학회지

BACKGROUND@#Brain abscess is a life-threatening condition that occurs due to complications during a neurosurgical procedure, direct cranial trauma, or the presence of local or distal infection. Infection in the oral cavity can also be considered a source of brain abscess.CASE PRESENTATION: A 45-year-old male patient was transported with brain abscess in the subcortical white matter. Navigation-guided abscess aspiration and drainage was performed in the right mid-frontal lobe, but the symptoms continued to worsen after the procedure. A panoramic radiograph showed alveolar bone resorption around the maxillary molars. The compromised maxillary molars were extracted under local anesthesia, and antibiotics were applied based on findings from bacterial culture. A brain MRI confirmed that the three brain abscesses in the frontal lobe were reduced in size, and the patient's symptoms began to improve after the extractions.@*CONCLUSION@#This is a rare case report about multiple uncontrolled brain abscesses treated by removal of infection through the extraction of maxillary molars with odontogenic infection. Untreated odontogenic infection can also be considered a cause of brain abscess. Therefore, it is necessary to recognize the possibility that untreated odontogenic infection can lead to serious systemic inflammatory diseases such as brain abscess. Through a multidisciplinary approach to diagnosis and treatment, physicians should be encouraged to consider odontogenic infections as a potential cause of brain abscesses.

The preliminary study for three-dimensional alveolar bone morphologic characteristics for alveolar bone restoration / 대한악안면성형재건외과학회지

BACKGROUND@#The concept of the ideal morphology for the alveolar bone form is an important element to reconstruct or restore the in maximizing esthetic profile and functional alveolar bone restoration. The purpose of this preliminary study is to evaluate the normal alveolar bone structure to provide the standard reference and guide template for use in diagnosing for implant placement, determining the correct amount of bone augmentation in actual clinical practice and producing prostheses based on three-dimensional imaging assessment of alveolar bone.@*METHODS@#This study was included 11 men and 11 women (average age, 22.6 and 24.5 years, respectively) selected from among 127 patients. The horizontal widths of alveolar bone of maxilla and mandible were measured at the crestal, mid-root, and root apex level on MDCT (multi-detector computed tomography) images reconstructed by medical imaging software. In addition, tooth dimensions of the central incisors, canines, second premolars, and first molars of maxilla and mandible, including the horizontal width of the interdental alveolar bone crest, were also measured and statistically analyzed.@*RESULTS@#The horizontal alveolar bone width of the palatal side of maxilla showed a distinct increment from the alveolar bone crest to the apical region in both anterior and posterior areas. The average widths of the maxillary alveolar ridge were as follows: central incisor, 7.43 mm; canine, 8.91 mm; second premolar, 9.57 mm; and first molar, 12.38 mm. The average widths of the mandibular alveolar ridge were as follows: central incisor, 6.21 mm; canine, 8.55 mm; second premolar, 8.45 mm; and first molar, 10.02 mm. In the buccal side, the alveolar bone width was not increased from the crest to the apical region. The horizontal alveolar bone width of an apical and mandibular border region was thinner than at the mid-root level.@*CONCLUSIONS@#The results of the preliminary study are useful as a clinical guideline when determining dental implant diameter and position. And also, these measurements can also be useful during the production of prefabricated membranes and customized alveolar bone scaffolds.

Gender-specific cephalometric features related to obesity in sleep apnea patients: trilogy of soft palate-mandible-hyoid bone / 대한악안면성형재건외과학회지

BACKGROUND@#The aim of this study is to investigate the relationship between gender-specific and obesity-related airway anatomy in patients with obstructive sleep apnea (OSA) by using cephalometric analyses.@*METHODS@#We retrospectively evaluated 206 patients with suspected OSA undergoing polysomnography and anthropometric measurements such as body mass index, neck circumference, and waist-hip ratio. We checked lateral cephalometry to measure tissue landmarks including angle from A point to nasion to B point (ANB), soft palate length (SPL), soft palate thickness (SPT), retropalatal space (RPS), retrolingual space (RLS), and mandibular plane to hyoid (MPH).@*RESULTS@#Male with OSA showed significantly increased SPL (P = .006) compared with controls. SPL and MPH had significant correlation with apnea-hypopnea index (AHI) and central obesity. Female with OSA showed significantly increased ANB (P = .013) and SPT (P = .004) compared with controls. The receiver operating characteristic curves revealed that SPT in male and ANB and SPT in female were significant in model 1 (AHI ≥ 5) and model 2 (AHI ≥ 15). MPH was also significant for male in model 2.@*CONCLUSION@#Male and female with OSA had distinct anatomic features of the upper airway and different interactions among soft palate, mandible, and hyoid bone.

Effects of nerve cells and adhesion molecules on nerve conduit for peripheral nerve regeneration

BACKGROUND: For peripheral nerve regeneration, recent attentions have been paid to the nerve conduits made by tissue-engineering technique. Three major elements of tissue-engineering are cells, molecules, and scaffolds. METHODS: In this study, the attachments of nerve cells, including Schwann cells, on the nerve conduit and the effects of both growth factor and adhesion molecule on these attachments were investigated. RESULTS: The attachment of rapidly-proliferating cells, C6 cells and HS683 cells, on nerve conduit was better than that of slowly-proliferating cells, PC12 cells and Schwann cells, however, the treatment of nerve growth factor improved the attachment of slowly-proliferating cells. In addition, the attachment of Schwann cells on nerve conduit coated with fibronectin was as good as that of Schwann cells treated with glial cell line-derived neurotrophic factor (GDNF). CONCLUSIONS: Growth factor changes nerve cell morphology and affects cell cycle time. And nerve growth factor or fibronectin treatment is indispensable for Schwann cell to be used for implantation in artificial nerve conduits.

Importance of Oral Environment for Environmental Hormones Interaction with Human Body for Future Research

There is increasing evidence that the environmental hormones may adversely affect the human body. The human reproductive system misrecognizes some of these endocrine disruptors with consequences to reproductive cell differentiation. Therefore, studies on the safety of these substances have been widely carried out to develop the science to create effective legislation to limit or prevent their use or require the development of inert, alternative substances. A few studies have reported that the oral cavity is the pathway for absorption of these substances released from plastic products or environmental hormone substances. This review suggests that the oral environment is vulnerable to exposure to environmental hormones and introduces supporting literature.

Correlation between depressive symptoms and subjective mastication ability and ability to pronunciation among Korean elderly / 한국역학회지

OBJECTIVES: The present study examines the relationship between depressive symptoms and subjective chewing and pronunciation ability in Korean seniors. Our goal is to provide the data required to develop appropriate oral health interventions programs for seniors. METHODS: The Center for Epidemiologic Studies-Depression Scale (CES-D) is widely used depressive symptoms assessment. A Korean version was used for the 2009 Community Health Survey, which was consulted to extract the present study's subjects, comprising 50,694 Korean seniors (males, 20,582; females, 30,112) aged ≥65 years. Those with a CES-D score ≥16 were rated 'depressed.' SAS version 9.3 was used for the data analysis. RESULTS: Prevalence of depressive symptoms increased as the subjects' socioeconomic status decreased, number of health issues increased, health behavior worsened, and chewing and pronunciation discomfort increased. Males with chewing difficulties were found to have 1.45 times (95% confidence interval [CI], 1.29 to 1.63) greater risk of depressive symptoms than those without, while males with pronunciation discomfort were found to have 1.97 times greater risk of depressive symptoms than those without (95% CI, 1.76 to 2.20). Females with chewing difficulty were found to have 1.50 times (95% CI, 1.39 to 1.61) greater risk of depressive symptoms than those without, and females with pronunciation discomfort were found to have 1.55 times greater risk of depressive symptoms than those without (95% CI, 1.44 to 1.67). CONCLUSIONS: Intervention programs designed to help with oral health management and alleviate depressive symptoms in seniors are urgently needed. As the prevalence of depressive symptoms may vary geographically, research examining potential variance at city, district, and town levels would be beneficial.

Bilateral dentigerous cysts that involve all four dental quadrants: a case report and literature review

Dentigerous cysts are common odontogenic cysts that are associated with the crown of the tooth and typically develop from single lesions. Bilateral and multiple dentigerous cysts are very rare and occur in patients with syndromic conditions. This paper presents a case report of a 15-year-old male patient that experienced non-syndromic bilateral dentigerous cysts that simultaneously occurred in all four dental quadrants around the unerupted third molars. Clinicians should confirm the extent of cystic lesions using a panoramic view and computed tomography, and should keep the possibility of bilateral dentigerous cysts in mind as a potential diagnosis, even in a non-syndromic patient.

Study on the trends in Korean clinical practice guidelines development

BACKGROUND: The definition of evidence-based clinical practice guidelines (CPGs) is "statements that are systematically developed to assist in the doctors' and patients' decision-making in certain situations." This study aims to establish the concept of evidence-based CPGs and investigate the development status to seek measures to apply evidence-based methods to CPG development for dental sedation in Korea. METHODS: The study conducted systematic searching methods based on evidence-based CPGs. Articles published between 1995 to 2015 were searched on a Korean database and the international database PubMed. The search was based on keywords related to four subjects (dentistry, clinical practice, guideline, recommendation). Two authors independently reviewed the searched articles to determine their analysis inclusion and the convergence stages, and to arrive at a conclusion through discussion. RESULTS: A total of 65 Korean CPGs were included. There were 51 medical guidelines, of which seven were dental and seven were Oriental medicine. CONCLUSIONS: As a basic direction for the development of evidence-based CPGs, this work suggests the following: increased awareness; consensus on the need to supply evidence-based development methods; education, computerization, and systematic observation of evidence-based CPG development methods; continuous research development and distribution of CPGs; and creation of a database for Korean clinical dentistry practice outcomes.

Cell attachment and proliferation of osteoblast-like MG63 cells on silk fibroin membrane for guided bone regeneration / 대한악안면성형재건외과학회지

BACKGROUND: The aim of this study is to verify the feasibility of using silk fibroin (SF) as a potential membrane for guided bone regeneration (GBR). METHODS: Various cellular responses (i.e., cell attachment, viability, and proliferation) of osteoblast-like MG63 cells cultured on an SF membrane were quantified. After culturing on an SF membrane for 1, 5, and 7 days, the attachment and surface morphology of MG63 cells were examined by optical and scanning electron microscopy (SEM), cell viability was determined using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and cell proliferation was quantified using 4',6-diamidino-2-phenylindole (DAPI) fluorescence staining. RESULTS: Optical microscopy revealed that MG63 cells cultured on the SF membrane proliferated over the 7-day observation period. The viability of cells cultured on SF membranes (SF group) and on control surfaces (control group) increased over time (P 0.05). In contrast, cell proliferation was significantly higher in the SF membrane group than in the control group at 7 days (P < 0.05). CONCLUSIONS: These results suggest that silk fibroin is a biocompatible material that could be used as a suitable alternative barrier membrane for GBR.

Developmental procedures for the clinical practice guidelines for conscious sedation in dentistry for the Korean Academy of Dental Sciences

BACKGROUND: Evidence-based clinical practice guidelines (CPGs) are defined as “statements that are scientifically reviewed about evidence and systematically developed to assist in the doctors' and patients' decision making in certain clinical situations.” This recommendation aims to promote good clinical practice for the provision of safe and effective practices of conscious sedation in dentistry. METHODS: The development of this clinical practice guideline was conducted by performing a systematic search of the literature for evidence-based CPGs. Existing guidelines, relevant systematic reviews, policy documents, legislation, or other recommendations were reviewed and appraised. To supplement this information, key questions were formulated by the Guideline Development Group and used as the basis for designing systematic literature search strategies to identify literature that may address these questions. Guideline documents were evaluated through a review of domestic and international databases for the development of a renewing of existing conscious sedation guidelines for dentistry. Clinical practice guidelines were critically appraised for their methodologies using Appraisal of guidelines for research and evaluation (AGREE) II. RESULTS: A total of 12 existing CPGs were included and 13 recommendations were made in a range of general, adult, and pediatric areas. CONCLUSION: The clinical practice guidelines for conscious sedation will be reviewed in 5 years' time for further updates to reflect significant changes in the field.

Preliminary evaluation of a three-dimensional, customized, and preformed titanium mesh in peri-implant alveolar bone regeneration

OBJECTIVES: The purpose of this preliminary study is to evaluate the effectiveness of a customized, three-dimensional, preformed titanium mesh as a barrier membrane for peri-implant alveolar bone regeneration. MATERIALS AND METHODS: Ten patients were recruited for this study. At the time of implant placement, all patients had fenestration or a dehiscence defect around the implant fixture. A mixture of particulate intraoral autologous bone and freeze-dried bone allograft was applied to the defect in a 1 : 1 volume ratio and covered by the preformed titanium mesh. A core biopsy specimen was taken from the regenerated bone four months postoperatively. Patients were followed for 12 months after the definitive prosthesis was placed. RESULTS: Satisfactory bone regeneration with limited fibrous tissue was detected beneath the preformed titanium mesh. Histologic findings revealed that newly formed bones were well-incorporated into the allografts and connective tissue. New growth was composed of approximately 80% vital bone, 5% fibrous marrow tissue, and 15% remaining allograft. All implants were functional without any significant complications. CONCLUSION: The use of preformed titanium mesh may support bone regeneration by maintaining space for new bone growth through its macro-pores. This preliminary study presents the efficacy of a preformed titanium mesh as a ready-to-use barrier membrane around peri-implant alveolar bone defect. This preformed mesh is also convenient to apply and to remove.

Analysis of gene expression during odontogenic differentiation of cultured human dental pulp cells

OBJECTIVES: We analyzed gene-expression profiles after 14 day odontogenic induction of human dental pulp cells (DPCs) using a DNA microarray and sought candidate genes possibly associated with mineralization. MATERIALS AND METHODS: Induced human dental pulp cells were obtained by culturing DPCs in odontogenic induction medium (OM) for 14 day. Cells exposed to normal culture medium were used as controls. Total RNA was extracted from cells and analyzed by microarray analysis and the key results were confirmed selectively by reverse-transcriptase polymerase chain reaction (RT-PCR). We also performed a gene set enrichment analysis (GSEA) of the microarray data. RESULTS: Six hundred and five genes among the 47,320 probes on the BeadChip differed by a factor of more than two-fold in the induced cells. Of these, 217 genes were upregulated, and 388 were down-regulated. GSEA revealed that in the induced cells, genes implicated in Apoptosis and Signaling by wingless MMTV integration (Wnt) were significantly upregulated. CONCLUSIONS: Genes implicated in Apoptosis and Signaling by Wnt are highly connected to the differentiation of dental pulp cells into odontoblast.

Evaluation of the feasibility of bony window repositioning without using a barrier membrane in sinus lateral approach

INTRODUCTION: In the lateral window approach for a maxillary sinus bone graft, there has been considerable controversy regarding the placement of a barrier membrane over the osteotomy site. In particular, when there is no damage to the Schneiderian membrane, clinicians should decide whether to use a barrier membrane or not, considering the benefits and costs. This study presents the clinical cases to demonstrate that only repositioning the detached window can lead to satisfactory bony healing of the grafted material without using a barrier membrane in the lateral approach for a maxillary sinus bone graft. MATERIALS AND METHODS: Five consecutive patients were treated with the same surgical procedures. After performing the antrostomy on the lateral maxillary wall using a round carbide bur and diamond bur, the bony window was detached by a gentle levering action. After confirming no perforation of the Schneiderian membrane, the grafting procedure was carried out the detached window of the lateral maxillary wall was repositioned over the grafted material without using a barrier membrane. A gross examination was carried out at the postoperative 6 month re-entry, and the the preoperative and postoperative dental computed tomography (CT) at re-entry were compared. RESULTS: All the procedures in the 5 patients went on to uneventful healing with no complications associated with the bone graft. Satisfactory bone regeneration without the interference of fibrous tissue on the gap between the repositioned window and lateral wall of the maxillary sinus was observed in the postoperative 6 month re-entry. The CT findings at re-entry revealed the, reconstruction of the external cortical plate including repositioned bony window. In addition, the loss of the discontinuity of the lateral maxillary wall was confirmed. CONCLUSION: This preliminary report showed that the detached window, which was just repositioned on the grafted material, could function as a barrier membrane in the lateral approach for a maxillary sinus bone graft. Therefore additional morphometric and histologic studies will be needed.

Alterations of Gene Expression by Beta-tricalcium Phosphate in Osteoblast-like MG63 Cells

The mRNA expression of MMP-1, TIMP-1, TGF-beta1 in gingival keratocytes from gingival hyperplasia induced by cyclosporine A

PURPOSE: Cyclosporine A (CsA) is a versatile immunosuppresive agent used to prevent graft rejection syndrome and treat autoimmune disease. One of the major side effects associated with CsA is the abnormal gingival hyperplasia. The purpose of this study was to investigate the relationship between the mRNA expression of the MMP-1, TIMP-1, and TGF-beta1 and the concentration of CsA in cultured human gingival keratinocytes. MATERIALS AND METHODS: Gingival keratocytes were obtained from gingival tissues of 4 healthy donors. The cultured gingival keratocytes were incubated with increasing concentrations of CsA (0-2000 ng/ml) for 24 hours and the expression of MMP-1, TIMP-1, and TGF-beta1 were determined by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: The expressions of MMP-1 and TGF-beta1 were not significantly different according to the concentrations of CsA. The expression of TIMP-1 was significantly increased at the CsA concentration of 500 ng/ml. CONCLUSION: We concluded that the gingival hyperplasia induced by CsA was more related with TIMP-1 than MMP-1 or TGF-beta1 on gingival collagen metabolism in patients treated with CsA.