Chronic osteomyelitis induced by the placement of dental implants on cemento-osseous dysplasia.

Cemento-osseous dysplasia is a well-known condition in which healthy bone becomes sclerotic. Hypovascularity of the lesion (caused by cementum-like deposits) increases the risk of secondary infection and osteomyelitis, which can also be induced by the placement of implants.

Predictive data mining for diagnosing periodontal disease: the Korea National Health and Nutrition Examination Surveys (KNHANES V and VI) from 2010 to 2015.

Objectives: This study aimed to identify patients with the highest risk of periodontal disease (PD), and to provide recommendations for the effective use and application of data mining (DM) techniques when establishing evidence-based dental-care policies for vulnerable groups at a high risk of PD.

Methods: This study used the SEMMA (Sample, Explore, Modify, Model, and Assess) methodology to construct DM models based on data acquired from the fifth and sixth Korea National Health and Nutrition Examination Surveys (2000-2015). We analyzed the sociodemographic and comorbidity variables that influence PD by applying the popular DM techniques of decision-tree, neural-network, and regression models, and also attempted to improve the predictive power and reliability by comparing the results obtained by these three models.

Panoramic radiography can be an effective diagnostic tool adjunctive to oral examinations in the national health checkup program.

Purpose: We investigated correlations between the findings of oral examinations and panoramic radiography in order to determine the efficacy of using panoramic radiographs in screening examinations.

Methods: This study included patients who visited dental clinics at National Health Insurance Service (NHIS) Ilsan Hospital for checkups during 2009-2015 and underwent panoramic radiographic examinations within 1 year prior to the oral examinations. Among the 48,006 patients who received checkups, 1,091 were included in this study.

Rotation tendency of the posteriorly displaced proximal segment after vertical ramus osteotomy.

Intraoral Vertical Ramus Osteotomy (IVRO) is one of the operative techniques used for orthognathic surgery. The aim of this study was to assess the posterior displacement of the proximal segment in patients undergoing IVRO at 1-year follow-up. In total, 52 hemimandibles from 26 patients who underwent IVRO in whom the proximal segment was posteriorly displaced without overlap with the distal segment at immediate post-operation (Imm) (30 cases, experimental group), and 26 patients in whom the proximal segment was not posteriorly displaced with overlap with the distal segment (Imm) (22 cases, control group) under three-dimensional computed tomography (3D CT) were included in the study.

Detection and diagnosis of dental caries using a deep learning-based convolutional neural network algorithm.

Objectives: Deep convolutional neural networks (CNNs) are a rapidly emerging new area of medical research, and have yielded impressive results in diagnosis and prediction in the fields of radiology and pathology. The aim of the current study was to evaluate the efficacy of deep CNN algorithms for detection and diagnosis of dental caries on periapical radiographs.

Materials And Methods: A total of 3000 periapical radiographic images were divided into a training and validation dataset (n = 2400 [80%]) and a test dataset (n = 600 [20%]).

Diagnosis and prediction of periodontally compromised teeth using a deep learning-based convolutional neural network algorithm.

Purpose: The aim of the current study was to develop a computer-assisted detection system based on a deep convolutional neural network (CNN) algorithm and to evaluate the potential usefulness and accuracy of this system for the diagnosis and prediction of periodontally compromised teeth (PCT).

Methods: Combining pretrained deep CNN architecture and a self-trained network, periapical radiographic images were used to determine the optimal CNN algorithm and weights. The diagnostic and predictive accuracy, sensitivity, specificity, positive predictive value, negative predictive value, receiver operating characteristic (ROC) curve, area under the ROC curve, confusion matrix, and 95% confidence intervals (CIs) were calculated using our deep CNN algorithm, based on a Keras framework in Python.

Charlson comorbidity index as a predictor of periodontal disease in elderly participants.

Purpose: This study investigated the validity of the Charlson comorbidity index (CCI) as a predictor of periodontal disease (PD) over a 12-year period.

Methods: Nationwide representative samples of 149,785 adults aged ≥60 years with PD (International Classification of Disease, 10th revision [ICD-10], K052-K056) were derived from the National Health Insurance Service-Elderly Cohort during 2002-2013. The degree of comorbidity was measured using the CCI (grade 0-6), including 17 diseases weighted on the basis of their association with mortality, and data were analyzed using multivariate Cox proportional-hazards regression in order to investigate the associations of comorbid diseases (CDs) with PD.

Sectioned images and 3D models of a cadaver head with reference to dermal filler injection.

The purpose of this study was to describe anatomical consideration with reference to dermal filler injection on sectioned images and three dimensional (3D) models using Visible Korean for medical education and clinical training purposes in the field of facial surgery. Serially sectioned images of the head were acquired from a cadaver. Anatomic structures related to dermal filler injection were 3D-reconstructed based on sectioned images, and additional structures were built on the basis of the established ones using a semi-automatic method.

Interdisciplinary treatment of a patient with multiple missing teeth and periodontitis.

A 49-year-old woman with several missing and periodontically compromised teeth was referred to the orthodontic department of National Health Insurance Service Ilsan Hospital by the periodontic department for interdisciplinary treatment. Multiple posterior teeth had been extracted 10 days earlier. Her chief complaint was crowding of the anterior teeth, and she wanted to improve both esthetics and function.

Sectioned images and surface models of a cadaver head with reference to botulinum neurotoxin injection.

Background: The aim of this study is to elucidate the anatomical considerations with reference to botulinum neurotoxin type A (BTX) injection, on sectioned images and surface models, using Visible Korean. These can be used for medical education and clinical training in the field of facial surgery.

Materials And Methods: Serially sectioned images of the head were obtained from a cadaver.

Trends in the incidence of tooth extraction due to periodontal disease: results of a 12-year longitudinal cohort study in South Korea.

Purpose: This study evaluated trends in tooth extraction due to acute and chronic periodontal disease (PD) using data from the National Health Insurance Service-National Sample Cohort for 2002-2013.

Methods: A random sample of 1,025,340 individuals was selected as a representative sample of the population, and a database (DB) of diagnostic and prescription codes was followed up for 12 years. We used multivariate logistic regression analysis to assess the incidence of total extraction (TE), extraction due to periodontal disease (EPD), and immediate extraction due to periodontal disease (IEPD) according to sociodemographic factors (sex, age, household income, health status, and area of residence).

Association between Periodontal disease and Prostate cancer: Results of a 12-year Longitudinal Cohort Study in South Korea.

The incidence of prostate cancer (PC) accompanying periodontal disease (PD) is anticipated to increase due to population aging. The aim of this study was to determine the association between PD and PC using data in the National Health Insurance Service-Health Examinee Cohort (NHIS-HEC). A random stratified sample of 187,934 South Koreans was collected from the NHIS database from 2002 to 2013.

Effect of periodontitis on the development of osteoporosis: results from a nationwide population-based cohort study (2003-2013).

Background: The prevalence of osteoporosis associated with the aging process is anticipated to increase along with the rising aging population. Periodontitis that the most common chronic infections of humankind is considered the risk factor for osteoporosis. The aim of this study was to identify the association between osteoporosis and periodontitis using a population-based cohort.

Marginal bone level changes in association with different vertical implant positions: a 3-year retrospective study.

Purpose: To retrospectively evaluate the relationship between the vertical position of the implant-abutment interface and marginal bone loss over 3 years using radiological analysis.

Methods: In total, 286 implant surfaces of 143 implants from 61 patients were analyzed. Panoramic radiographic images were taken immediately after implant installation and at 6, 12, and 36 months after loading.

Association between periodontal disease and non-communicable diseases: A 12-year longitudinal health-examinee cohort study in South Korea.

The National Health Insurance Service-Health Examinee Cohort during 2002 to 2013 was used to investigate the associations between periodontal disease (PD) and the following non-communicable diseases (NCDs): hypertension, diabetes mellitus, osteoporosis, cerebral infarction, angina pectoris, myocardial infarction, and obesity.Univariate and multivariate logistic regression analyses adjusting for potential confounders during the follow-up period-including age, sex, household income, insurance status, residence area, health status, and comorbidities-were used to estimated odds ratios (ORs) with 95% confidence intervals (CIs) in order to assess the associations between PD and NCDs.We enrolled 200,026 patients with PD and 154,824 subjects with a healthy oral status.

Spontaneous Union of an Accidentally Fractured Proximal Segment During Vertical Ramus Osteotomy.

After sawing in the intraoral vertical ramus osteotomy, in the case of an incomplete amputation, the proximal segment is split using the osteotome. Unfortunately, in this case, the proximal segment was accidentally fractured. The operation was completed without performing any other fixation.

Association between periodontal flap surgery for periodontitis and vasculogenic erectile dysfunction in Koreans.

Purpose: The National Health Insurance Service-National Sample Cohort and medical checkup data from 2002 to 2013 were used to evaluate the association between periodontal surgery for the treatment of periodontitis (PSTP) and vasculogenic erectile dysfunction (VED).

Methods: Bivariate and multivariate logistic regression analyses were applied to a longitudinal retrospective database to assess the association between PSTP and VED while adjusting for the potential confounding effects of sociodemographic factors (age, household income, insurance status, health status, residence area, and smoking status) and comorbidities (diabetes mellitus, angina pectoris, cerebral infarction, and myocardial infarction).

Results: Among the 7,148 PSTP within the 268,296 recruited subjects, the overall prevalence of VED in PSTP was 1.

Association between dental implants in the posterior region and traumatic occlusion in the adjacent premolars: a long-term follow-up clinical and radiographic analysis.

Purpose: The aim of this retrospective study was to determine the association between dental implants in the posterior region and traumatic occlusion in the adjacent premolars, using data collected during from 2002 to 2015.

Methods: Traumatic occlusion in the adjacent premolars was assessed by examining clinical parameters (bleeding on probing, probing pocket depth, fremitus, and tooth mobility) and radiographic parameters (loss of supporting bone and widening of the periodontal ligament space) over a mean follow-up of 5 years. Clinical factors (gender, age, implant type, maxillary or mandibular position, opposing teeth, and duration of functional loading) were evaluated statistically in order to characterize the relationship between implants in the posterior region and traumatic occlusion in the adjacent premolars.

Sectioned images and surface models of a cadaver for understanding the free vascularised anterior rib flap.

Background: The purpose of this study is to describe the vascularised anterior rib flap on sectioned images and surface models using Visible Korean for medical education and clinical training in the field of mandibular reconstructive surgery.

Materials And Methods: Serially sectioned images of the thorax were obtained from a cadaver. Significant structures in the sectioned images were outlined and stacked to create a surface model.

National dental policies and socio-demographic factors affecting changes in the incidence of periodontal treatments in Korean: A nationwide population-based retrospective cohort study from 2002-2013.

Background: Dental insurance coverage has recently expanded in Korea. The number of patients diagnosed with periodontal disease (PD), and the actual number of periodontally compromised patients has increased. However, few studies have investigated the relationships between the prevalence of periodontal disease and the incidence of PD treatment, dental insurance policies, and socio-demographic factors.

Four-week histologic evaluation of grafted calvarial defects with adjunctive hyperbaric oxygen therapy in rats.

Purpose: The aim of this study was to characterize the healing in the grafted calvarial defects of rats after adjunctive hyperbaric oxygen therapy.

Methods: Twenty-eight male Sprague-Dawley rats (body weight, 250-300 g) were randomly divided into two treatment groups: with hyperbaric oxygen therapy (HBO; n=14) and without HBO (NHBO; n=14). Each group was further subdivided according to the bone substitute applied: biphasic calcium phosphate (BCP; n=7) and surface-modified BCP (mBCP; n=7).

Characteristics of temporomandibular joint structures after mandibular condyle fractures revealed by magnetic resonance imaging.

Background: This study aimed to evaluate the structural changes of temporomandibular joint immediately after condylar fractures with magnetic resonance imaging (MRI).

Method: We evaluated 34 subjects of condylar fractures with MRI. The position, shape, and signal intensity of the condyle, disc, and retrodiscal tissue were analyzed with MR images.

Percutaneous self-injury to the femoral region caused by bur breakage during surgical extraction of a patient's impacted third molar.

Extraction of an impacted third molar is one of the most frequently performed techniques in oral and maxillofacial surgery. Surgeons can suffer numerous external injuries while extracting a tooth, with percutaneous injuries to the hand being the most commonly reported. In this article, we present a case involving a percutaneous injury of the surgeon's femoral region caused by breakage of the fissure bur connected to the handpiece during extraction of the third molar.