Identification of dental implant systems from low-quality and distorted dental radiographs using AI trained on a large multi-center dataset.

Most artificial intelligence (AI) studies have attempted to identify dental implant systems (DISs) while excluding low-quality and distorted dental radiographs, limiting their actual clinical use. This study aimed to evaluate the effectiveness of an AI model, trained on a large and multi-center dataset, in identifying different types of DIS in low-quality and distorted dental radiographs. Based on the fine-tuned pre-trained ResNet-50 algorithm, 156,965 panoramic and periapical radiological images were used as training and validation datasets, and 530 low-quality and distorted images of four types (including those not perpendicular to the axis of the fixture, radiation overexposure, cut off the apex of the fixture, and containing foreign bodies) were used as test datasets. Moreover, the accuracy performance of low-quality and distorted DIS classification was compared using AI and five periodontists. Based on a test dataset, the performance evaluation of the AI model achieved accuracy, precision, recall, and F1 score metrics of 95.05%, 95.91%, 92.49%, and 94.17%, respectively. However, five periodontists performed the classification of nine types of DISs based on four different types of low-quality and distorted radiographs, achieving a mean overall accuracy of 37.2 ± 29.0%. Within the limitations of this study, AI demonstrated superior accuracy in identifying DIS from low-quality or distorted radiographs, outperforming dental professionals in classification tasks. However, for actual clinical application of AI, extensive standardization research on low-quality and distorted radiographic images is essential.

Evidence of the existence of multiple modules for the stroke-caused flexion synergy from Fugl-Meyer assessment scores.

Stroke-caused synergies may result from preferential use of the reticulospinal tract (RST) due to damage to the corticospinal tract. The RST branches multiple motoneuron pools across the arm together resulting in gross motor control or muscle synergies, and accordingly the controllability of individual muscles is reduced. It is not clear whether the muscles involuntarily activated by abnormal synergy vary with the muscles voluntarily activated when motor commands descend through the RST. Studies showed that abnormal synergies may originate from merging and re-weighting of synergies individuals without neurological deficit. This leads to a hypothesis that those abnormal synergies are still selectively excited depending on the context. In this study, we test this hypothesis, leveraging the Fugl-Meyer assessment (FMA) that could characterize the neuroanatomical architecture in individuals with a wide range of impairment. We examine the ability to perform an out-of-synergy movement with the flexion synergy caused by either shoulder or elbow loading. The results reveal that about 14% (8/57, 95%CI: [5.0%, 23.1%]) of the participants with severe impairment (total FM score <29) in the chronic phase (6 months after stroke) are able to keep the elbow extended during shoulder loading and keep the shoulder at neutral during elbow loading. Those participants undergo a different course of neural reorganization which enhanced abnormal synergies in comparison with individuals with mild impairment (p<0.05). These results evidence that separate routes and synergy modules to motoneuron pools across the arm might exist even if the motor command is mediated possibly via the RST.

Correlations in abnormal synergies between the upper and lower extremities across various phases of stroke.

BACKGROUND AND OBJECTIVES: The flexion synergy and extension synergy are a representative consequence of a stroke and appear in the upper extremity and lower extremity. Since the ipsilesional corticospinal tract (CST) is the most influential neural pathway for both extremities in motor execution, damage by a stroke to this tract could lead to similar motor pathological features (e.g., abnormal synergies) in both extremities. However, less attention has been paid to the inter-limb correlations in the flexion synergy and extension synergy across different recovery phases of a stroke. METHODS: We used results of the Fugl-Meyer assessment (FMA) to characterize those correlations in a total of 512 participants with hemiparesis post stroke from the acute phase to 1 year. The FMA provides indirect indicators of the degrees of the flexion synergy and extension synergy post stroke. RESULTS: We found that generally, strong inter-limb correlations (r>0.65 with all p-values<0.0001) between the flexion synergy and extension synergy appeared in the acute-to-subacute phase (<90 days). But correlations of lower-extremity extension synergy with upper-extremity flexion synergy and extension synergy decreased (down to r=0.38) around 360 days after stroke (p<0.05). DISCUSSION: These results suggest that preferential use of alternative neural pathways after damage by a stroke to the CST enhances inter-limb correlations between the flexion synergy and extension but a recovery of the CST functional and the fragmentation (remodeling) of the alternative neural substrates in the chronic phase contribute to diversity in neural pathways in motor execution, eventually leading to reduced inter-limb correlations.

Interactions in abnormal synergies between the upper and lower extremities in various phases of stroke: A cohort study.

Objective: The flexion synergy and extension synergy are a representative consequence of a stroke and appear in the upper extremity and lower extremity. Since the ipsilesional corticospinal tract (CST) is the most influential neural pathway for both extremities in motor execution, damage by a stroke to this tract could lead to similar motor pathological features (e.g., abnormal synergies) in both extremities. However less attention has been paid to the inter-limb correlations in the flexion synergy and extension synergy across different recovery phases of a stroke. Methods: In this study, we used results of the Fugl-Meyer assessment (FMA) to characterize those correlations in a total of 512 participants with hemiparesis post stroke from the acute phase to 1 year. The FMA provides indirect indicators of the degrees of the flexion synergy and extension synergy post stroke. Results: We found that generally, strong inter-limb correlations (r>0.65 with all p-values<0.0001) between the flexion synergy and extension synergy appeared in the acute-to-subacute phase (<90 days). But correlations of lower-extremity extension synergy with upper-extremity flexion synergy and extension synergy decreased (down to r=0.38) around 360 days after stroke (p<0.05). Interpretation: These results suggest that the preferential use of alternative neural pathways after damage by a stroke to the CST enhances inter-limb correlations between the flexion synergy and extension, however a recovery of the CST or/and the functional fragmentation (remodeling) of the alternative neural substrates in the chronic phase contribute to diversity in neural pathways in motor execution, eventually leading to reduced inter-limb correlations.

Comparing the clinical effects of local administration of minocycline ointment and doxycycline solution in the treatment of acute periodontal abscesses: a retrospective clinical study.

PURPOSE: The objective of this retrospective clinical study was to provide evidence supporting the adjunctive local application of doxycycline solution or minocycline ointment, in conjunction with drainage, for the treatment of acute periodontal abscesses. METHODS: The study included 63 patients who had received treatment for acute periodontal abscesses through drainage supplemented with 1 of 3 types of adjunctive medications during their initial visit (visit 1; baseline): 1) saline irrigation (the control group), 2) 2% minocycline ointment (the TM group), or 3) 300 mg/mL doxycycline irrigation (the TD group). The same adjunctive medication was administered at visit 2, which took place 1 week after visit 1. Probing depth (PD), bleeding on probing (BOP), plaque index, gingival recession, clinical attachment level, and tooth mobility were clinically evaluated at visits 1, 2, and a third visit (visit 3; 4 weeks after visit 1). Statistical significance was considered to be indicated by P values <0.05. RESULTS: By visit 3, all clinical indices and tooth mobility had significantly decreased in each group. At this visit, PD and BOP on the abscess side were significantly lower in the TM and TD groups compared to the control group. The TD group showed a significantly greater improvement than the TM group, with mean PD reductions of 1.09 mm in the control group, 1.88 mm in the TM group, and 2.88 mm in the TD group. Similarly, mean BOP reductions were 45% in the control group, 73.02% in the TM group, and 95.45% in the TD group. CONCLUSIONS: Local and adjunctive administration of doxycycline and minocycline in combination with drainage exhibited clinical advantages over drainage alone in improving PD and BOP. Notably, a doxycycline solution of 300 mg/mL was more effective than a 2% minocycline ointment.

Clustering and prediction of long-term functional recovery patterns in first-time stroke patients.

Objectives: The purpose of this study was to cluster long-term multifaceted functional recovery patterns and to establish prediction models for functional outcome in first-time stroke patients using unsupervised machine learning. Methods: This study is an interim analysis of the dataset from the Korean Stroke Cohort for Functioning and Rehabilitation (KOSCO), a long-term, prospective, multicenter cohort study of first-time stroke patients. The KOSCO screened 10,636 first-time stroke patients admitted to nine representative hospitals in Korea during a three-year recruitment period, and 7,858 patients agreed to enroll. Early clinical and demographic features of stroke patients and six multifaceted functional assessment scores measured from 7 days to 24 months after stroke onset were used as input variables. K-means clustering analysis was performed, and prediction models were generated and validated using machine learning. Results: A total of 5,534 stroke patients (4,388 ischemic and 1,146 hemorrhagic; mean age 63·31 ± 12·86; 3,253 [58.78%] male) completed functional assessments 24 months after stroke onset. Through K-means clustering, ischemic stroke (IS) patients were clustered into five groups and hemorrhagic stroke (HS) patients into four groups. Each cluster had distinct clinical characteristics and functional recovery patterns. The final prediction models for IS and HS patients achieved relatively high prediction accuracies of 0.926 and 0.887, respectively. Conclusions: The longitudinal, multi-dimensional, functional assessment data of first-time stroke patients were successfully clustered, and the prediction models showed relatively good accuracies. Early identification and prediction of long-term functional outcomes will help clinicians develop customized treatment strategies.

Efficacy of active noise-canceling headphones in patients undergoing ultrasonic scaling.

PURPOSE: Dental fear hinders patients from receiving appropriate dental treatment. In particular, the noise generated by high-speed air turbines and ultrasonic scalers can adversely affect patients. Many efforts have been made to reduce the discomfort caused by noise, but no methods are definitively recommended. The purpose of this study was to determine the efficacy of active noise-canceling (ANC) headphones in reducing the pain and discomfort associated with dental scaling. METHODS: Fifty-five patients requiring scaling and root planing, aged ≥19 years and showing no auditory problems, were included. Scaling was performed for the bilateral maxillary molars and premolars while patients wore headphones, with ANC turned either on or off. The degree of noise and pain reduction in the on and off conditions were surveyed using a visual analog scale (VAS). The Wilcoxon signed-rank test was performed to compare noise- and pain-related discomfort with ANC turned on and off. RESULTS: The sample included 28 men and 27 women with a mean age of 45.45±13.12 years. The average noise-related discomfort score was 3.84±2.12 and 2.95±1.99 when noise-canceling was turned off and on, respectively, with a statistically significant difference (P<0.05). Similarly, the average pain-related discomfort score was 3.78±2.00 and 3.09±1.96 when noise-canceling was turned off and on, respectively, which was a statistically significant difference (P<0.05). CONCLUSIONS: The use of ANC headphones seems to reduce the discomfort caused by noise and pain in patients undergoing scaling. TRIAL REGISTRATION: Clinical Research Information Service Identifier: KCT0007093.

Long-term outcomes after peri-implantitis treatment and their influencing factors: a retrospective study.

PURPOSE: This study aimed to determine the long-term outcomes after peri-implantitis treatment and the factors affecting these outcomes. METHODS: This study included 92 implants in 45 patients who had been treated for peri-implantitis. Clinical data on the characteristics of patients and their implants were collected retrospectively. The change in the marginal bone level was calculated by comparing the baseline and the most recently obtained (≥3 years after treatment) radiographs. The primary outcome variable was progression of the disease after the treatment at the implant level, which was defined as further bone loss of >1.0 mm or implant removal. A 2-level binary logistic regression analysis was used to identify the effects of possible factors on the primary outcome. RESULTS: The mean age of the patients was 58.7 years (range, 22-79 years). Progression of peri-implantitis was observed in 64.4% of patients and 63.0% of implants during an observation period of 6.4±2.7 years (mean±standard deviation). Multivariable regression analysis revealed that full compliance to recall visits (P=0.019), smoking (P=0.023), placement of 4 or more implants (P=0.022), and marginal bone loss ≥4 mm at baseline (P=0.027) significantly influenced the treatment outcome. CONCLUSIONS: The long-term results of peri-implantitis treatment can be improved by full compliance on the part of patients, whereas it is impaired by smoking, placement of multiple implants, and severe bone loss at baseline. Encouraging patients to stop smoking and to receive supportive care is recommended before treatment.

Deep learning improves implant classification by dental professionals: a multi-center evaluation of accuracy and efficiency.

PURPOSE: The aim of this study was to evaluate and compare the accuracy performance of dental professionals in the classification of different types of dental implant systems (DISs) using panoramic radiographic images with and without the assistance of a deep learning (DL) algorithm. METHODS: Using a self-reported questionnaire, the classification accuracy of dental professionals (including 5 board-certified periodontists, 8 periodontology residents, and 31 dentists not specialized in implantology working at 3 dental hospitals) with and without the assistance of an automated DL algorithm were determined and compared. The accuracy, sensitivity, specificity, confusion matrix, receiver operating characteristic (ROC) curves, and area under the ROC curves were calculated to evaluate the classification performance of the DL algorithm and dental professionals. RESULTS: Using the DL algorithm led to a statistically significant improvement in the average classification accuracy of DISs (mean accuracy: 78.88%) compared to that without the assistance of the DL algorithm (mean accuracy: 63.13%, P<0.05). In particular, when assisted by the DL algorithm, board-certified periodontists (mean accuracy: 88.56%) showed higher average accuracy than did the DL algorithm, and dentists not specialized in implantology (mean accuracy: 77.83%) showed the largest improvement, reaching an average accuracy similar to that of the algorithm (mean accuracy: 80.56%). CONCLUSIONS: The automated DL algorithm classified DISs with accuracy and performance comparable to those of board-certified periodontists, and it may be useful for dental professionals for the classification of various types of DISs encountered in clinical practice.

Evaluation of failed implants and reimplantation at sites of previous dental implant failure: survival rates and risk factors.

PURPOSE: The purpose of this study was to evaluate failed implants and reimplantation survival and to identify the relative risk factors for implant re-failure. METHODS: Ninety-one dental implants were extracted between 2006 and 2020 at the National Health Insurance Service Ilsan Hospital, including 56 implants in the maxilla and 35 implants in the mandible that were removed from 77 patients. Patient information (e.g., age, sex, and systemic diseases) and surgical information (e.g., the date of surgery and location of the implants and bone grafts) were recorded. If an implant prosthesis was used, prosthesis information was also recorded. RESULTS: In total, 91 first-time failed dental implants in 77 patients were analyzed. Of them, 69 implants in 61 patients received reimplantation after failure. Sixteen patients (22 implants) refused reimplantation or received reimplantation at a different site. Eight of the 69 reimplants failed again. The 1-year survival rate of the 69 reimplants was 89.4%. Age at reimplantation and smoking significantly increased the risk of reimplantation failure. However, a history of taking anti-thrombotic agents showed a statistically significant negative association with reimplantation failure. Of the failed implants, 66% showed early failure and 34% showed late failure of the initial implantation. All 8 re-failed implants showed early failure. Only 3 of these 8 failed reimplants were re-tried and the second reimplants all survived. CONCLUSIONS: The total survival rate of implants, which included reimplants and second reimplants was 99.2%, although the survival rate of the initial implantations was 96.3%. Previous failure did not affect the success of the next trial. Reimplantation failure was more strongly affected by patient factors than by implant factors. Therefore, each patient's specific factors need to be meticulously controlled to achieve successful reimplantation.

Sexual Violence as a Key Predictor of Depressive Symptoms in Women: Korean Longitudinal Survey of Women and Families.

The purpose of this study was to identify the influence of violence on depressive symptoms in women. We analyzed panel data from the Korean Longitudinal Survey of Women and Families (n = 6,632). Exposure to sexual violence was a significant predictor of the onset of depressive symptoms. After adjusting for all covariates, other predictors included the perception of a poor or very poor health status than normal and participants in their 40s and 50s versus participants younger than 40 years. Assessing exposure to sexual violence might be beneficial for evaluating depressive symptoms in women who are newly diagnosed with depression.

Nurse turnover: A longitudinal survival analysis of the Korea Nurses' Health Study.

AIMS: To identify factors influencing turnover among Korean female nurses from a longitudinal perspective. DESIGN: A national cohort study called the Korea Nurses' Health Study (2013-2020) was used. METHODS: A national sample of female nurses from module 1 (N = 20,613, 2013-2014), module 5 (N = 11,527, 2016-2017), module 7 (N = 8,658, 2018-2019) and module 8 (N = 10,253, 2019-2020) was used. Based on a nurse turnover model, individual, health-related, social work environment and work organizational factors were considered explainable variables for nurse turnover. Kaplan-Meier survival analysis and multivariate Cox regression analysis were used to identify the factors influencing female nurse turnover in South Korea. RESULTS: Female nurses who had less education, were unmarried, were pregnant, and had higher stress levels and an increased probability of experiencing turnover as they aged. Those who perceived moderate health rather than good/very good health, had depressive symptoms, had a higher salary, were charge nurses/unit managers/supervisors or advanced practice nurses, were advanced practice nurses rather than registered nurses, worked shifts, worked in special care units or outpatient wards/administration as opposed to general wards, and worked in larger hospitals had a decreased probability of experiencing turnover as they aged. A two-way interaction analysis revealed that those who had depressive symptoms and increased perceived stress were more likely to experience turnover as they aged. CONCLUSION: Multiple factors influenced female nurse turnover, including individual, health-related, social work environment and work organizational factors. A multidimensional approach is needed to reduce nurse turnover. IMPACT: Various factors predict nurse turnover as nurses age, implying that a multifaceted approach is needed to manage nurse turnover. The influence of depressive symptoms on turnover should be evaluated by considering the perceived stress level. Nursing managers and policy makers could use our results to develop programs/policies to reduce nurse turnover.

Adjunctive use of metronidazole-minocycline ointment in the nonsurgical treatment of peri-implantitis: A multicenter randomized controlled trial.

BACKGROUND: Clinical benefits of local antibiotics as an adjunct to nonsurgical treatment of peri-implantitis have been widely reported, but most studies evaluated incipient peri-implantitis lesions, and showed incomplete treatment success rates. PURPOSE: To assess the clinical and microbiological outcomes of administering metronidazole in combination with minocycline as a local adjunct to the nonsurgical treatment of peri-implantitis. MATERIALS AND METHODS: One hundred and eighteen subjects with peri-implantitis were recruited in a four-center, three-arm, and 12-week randomized controlled trial. Subjects were randomly assigned to receive one of the following treatments: (a) MM-mechanical debridement + metronidazole-minocycline ointment, (b) MC-mechanical debridement + minocycline ointment, (c) NST-mechanical debridement only. RESULTS: Except for four subjects who was excluded during the trial, a total of 114 patients with 114 implants (one implant per each patient) finally completed the trial and were included in the analyses. Multivariate logistic regression analysis revealed that the treatment success rates (absence of bleeding or suppuration on probing, and sites showing pocket probing depth [PPD] ≥5 mm) on at 12 weeks were higher in MM-group patients (31.6%) and MC-group patients (20.5%) compared to NST-group patients (2.7%; p = 0.011 and 0.040, respectively). Subjects with deepest PPD ≥8 mm showed a significant difference in the PPD reduction between MM and MC groups at week 4 (p = 0.025) and week 12 (p = 0.047). Detection ratio of Tannerella forsythia was significantly lower for MM group than MC group (p = 0.038). CONCLUSIONS: Additive use of either MM or MC results in significantly higher treatment success rates compared to sole mechanical debridement in nonsurgical treatment of peri-implantitis. Moreover, MM contributes to a significantly greater reduction in the PPD compared to MC in deep pockets (cris.nih.go.kr KCT0004557).

Trends in health behaviors over 20 years: findings from the 1998-2018 Korea National Health and Nutrition Examination Survey.

OBJECTIVES: This study aimed to examine the trends in health behaviors in Korean population using data from the Korea National Health and Nutrition Examination Survey (KNHANES). METHODS: The subjects were 96,408 adults aged 19 years or older who participated in the first (1998) through seventh (2016-2018) KNHANES health interview. The prevalence of health behaviors (cigarette smoking, alcohol drinking, and physical activity) and annual percent change (APC) were estimated using SAS and the Joinpoint program. RESULTS: The prevalence of current cigarette smoking in men decreased by 2.8%p (APC= -2.8, p< 0.001) annually over the 20-year period, and the prevalence of exposure to secondhand smoke at home substantially decreased compared to 2005 (APC= -8.8, p< 0.001). Compared to 2005, the prevalence of current alcohol drinking in women, but not men, increased (APC= 2.0, p< 0.001), and the prevalence of binge drinking decreased in men (APC= -0.7, p< 0.001) and increased in women (APC= 2.4, p< 0.001). The prevalence of aerobic physical activity decreased from 2014 in both gendersd (p< 0.001). The prevalence of healthy behaviors practice (non-smoking, alcohol abstinence, and aerobic physical activity) was down-trending (APC= -5.3, p< 0.001), especially among women (APC= -6.4, p< 0.001). CONCLUSIONS: Over the past 20 years, smoking behaviors improved. However, drinking behavior was unchanged and physical activity indicators markedly decreased. More active programs are necessary for improving health behaviors, which are major risk factors linked to chronic diseases.

Effects of Community-Based Interventions on Medication Adherence and Hospitalization for Elderly Patients with Type 2 Diabetes at Primary Care Clinics in South Korea.

Korean Disease Control and Prevention Agency launched Control and Prevention Community-based Registration and Management for Hypertension and Diabetes mellitus Project (CRMHDP) in Gwangmyeong city, 2009. This project has provided incentives on both patient and physician and has made private clinics and Public Health Center (PHC) in a community collaborate for effective chronic disease management among elderly people. This study aimed to evaluate the effects of CRMHDP on medication compliance and hospitalization due to diabetes-specific complications. The retrospective cohort study design was based on data of Korean National Health Insurance (KNHI) with 2 control areas (A & B) with usual primary care service similar to Gwangmyeong city regarding community health resources. The data on the study subjects were examined for the following 5 years since the baseline point. Medication adherence rates of CRMHDP-enrollees after the project was significantly higher than two control groups. For the hospitalization due to any complications, adjusted hazard ratio in the intervention group, compared to the control group A and B, were 0.76 (95% Confidence Interval: 0.65-0.78) and 0.52 (95% Confidence Interval 0.41-0.78), respectively. CRMHDP could successful in improving the management of type 2 diabetes mellitus among elderly people in South Korean primary care settings.

Comparison of causes for suicidal ideation and attempt: Korean Longitudinal Survey of Women and Families.

The purpose of this study was to identify factors that influence suicidal ideation and attempts among Korean women, using longitudinal data. Data from wave 4 (n = 7227), wave 5 (n = 6892), and wave 6 (n = 6632) of the Korean Longitudinal Survey of Women and Families collected on 2012, 2014, and 2016 were subjected to Kaplan-Meier and Cox regression analysis. Number of cases for suicidal ideation was 4.7% of the total cases (n = 20,751) between wave 4 through 6; number of cases for suicidal attempts was 5.7% of the cases from suicide ideation (n = 979). Depressive feelings, bad or worst health, and increased stress had significant impacts on suicidal ideation (χ2 = 1867.84, p < .001; χ2 = 983.61, p < .001; χ2 = 884.01, p < .001) and suicidal attempts (χ2 = 5.36, p < .05; χ2 = 11.19, p < .01; χ2 = 7.46, p < .05; χ2 = 6.21, p < .05) over time, respectively. From the Cox regression analysis, non-marital status (OR = 2.50, CI = 1.40-4.48) and having more than two children (OR = 2.55, CI = 1.18-5.51) compared to not having children were identified as predictors for suicidal attempt. Although the negative effect of number of children on suicidal attempts conflicts with previous evidence, socially determined mother roles and the significance of children should be considered in culturally sensitive terms when interpreting our findings.

Complication rates for various retention types in anterior implant-supported prostheses: A retrospective clinical study.

STATEMENT OF PROBLEM: Implant-supported prostheses have typically been retained by cement or screws, each of which has advantages and disadvantages. Two new types of prosthesis with complementary advantages and disadvantages have been proposed: the screw- and cement-retained prosthesis, which combines cement and screw retention, and the antiloosening inner-post screw (ALIPS) type, which uses lateral screws. Both esthetic and functional factors should be considered for anterior prostheses; however, clinical studies of the complication rates of these designs are lacking. PURPOSE: The purpose of this retrospective clinical study was to evaluate the complications of dental implant-supported restorations with various prosthetic types in the anterior region and to analyze other factors that affect complications. MATERIAL AND METHODS: This study included 51 patients who had 83 implants placed in the anterior region by a single clinician between August 2009 and December 2016. Surgical and prosthetic features were recorded, and implant complications were analyzed. RESULTS: There were 45 (55.4%) cement-retained implants, 5 (6.0%) screw- and cement-retained prosthesis implants, and 32 (38.6%) ALIPS-retained implants. Peri-implant mucositis was observed most frequently in the ALIPS type (21.9%), but the biological complications did not differ significantly with the prosthetic type. The most common mechanical complication was loss of retention in the cement type of prosthesis (30.4%) and screw loosening in the ALIPS type (43.8%). Implant complications varied with position (maxilla or mandible) and implantation timing (period from tooth extraction to implant placement). CONCLUSIONS: The complications of implants placed in the anterior region were affected by different factors but did not differ significantly with the type of the retention.

A Performance Comparison between Automated Deep Learning and Dental Professionals in Classification of Dental Implant Systems from Dental Imaging: A Multi-Center Study.

In this study, the efficacy of the automated deep convolutional neural network (DCNN) was evaluated for the classification of dental implant systems (DISs) and the accuracy of the performance was compared against that of dental professionals using dental radiographic images collected from three dental hospitals. A total of 11,980 panoramic and periapical radiographic images with six different types of DISs were divided into training (n = 9584) and testing (n = 2396) datasets. To compare the accuracy of the trained automated DCNN with dental professionals (including six board-certified periodontists, eight periodontology residents, and 11 residents not specialized in periodontology), 180 images were randomly selected from the test dataset. The accuracy of the automated DCNN based on the AUC, Youden index, sensitivity, and specificity, were 0.954, 0.808, 0.955, and 0.853, respectively. The automated DCNN outperformed most of the participating dental professionals, including board-certified periodontists, periodontal residents, and residents not specialized in periodontology. The automated DCNN was highly effective in classifying similar shapes of different types of DISs based on dental radiographic images. Further studies are necessary to determine the efficacy and feasibility of applying an automated DCNN in clinical practice.

Gender Differences in the Relationship between Type 2 Diabetes Mellitus and Employment: Evidence from the Korea Health Panel Study.

Previous studies have analyzed the impact of diabetes mellitus on labor market participation by men and women, but gender difference between type 2 diabetes mellitus (T2DM) and employment has not been the focus. This study aims to explore gender differences between T2DM and employment status. Data from the Korea Health Panel Study, 2013-2015 were analyzed by distinguishingT2DM and non-diabetes (N = 11,216). The empirical model was established and the generalized two-stage least squares (2SLS) was estimated, controlling for endogeneity. A family history of diabetes, as an instrumental variable, was related to an individual's genetic predisposition to develop diabetes. The estimated results for the 2SLS showed the interaction effects between T2DM and employment. T2DM had a statistically significant and negative effect on employment for women only. The comparison with non-diabetes showed that women with T2DM had a lower probability of employment by 51.9% (p < 0.05). Exposing gender bias in employment suggests that healthcare policies and disease management programs for diabetic patients should adopt gender-specific remedies.

Supraeruption as a consideration for implant restoration.

PURPOSE: The aim of this study was to compare the prevalence, amount, and rate of supraeruption of the maxillary second molar according to sex, age, and history of periodontitis. METHODS: Data were collected retrospectively from the charts and panoramic radiographs of 65 patients who were scheduled to undergo implant placement at the site of the mandibular second molar. The amount of supraeruption of the maxillary second molar and the alveolar bone level of the neighboring teeth were measured on digital panoramic radiographs. The prevalence was evaluated in each group, and univariate and multivariate logistic regression analyses were used to identify factors influencing the prevalence of supraeruption. The amount and the rate of supraeruption were compared between pairs of groups using the Mann-Whitney U test. For all tests, P values <0.05 were considered to indicate statistical significance. RESULTS: Supraeruption occurred in 78% of the patients. The prevalence of supraeruption was affected by sex, age, and history of periodontitis. The mean amount of supraeruption was 0.91 mm and the mean rate of supraeruption was 0.14 mm/month. The amount and the rate of supraeruption showed no significant differences according to sex, age, or the distance from the cementoenamel junction to the alveolar bone crest (P>0.05). CONCLUSIONS: These results show that the amount of supraeruption on the maxillary second molar was similar to the thickness of the enamel on the occlusal surface. When a single implant is scheduled to be placed on the mandibular second molar, supraeruption of the antagonist should be considered.