Distant migration of copolyamide breast filler following mammography: a case report

Copolyamide fillers, such as Aquafilling, have been used off-label for breast augmentation in many countries, including Korea. However, safety concerns have arisen due to reported complications, including induration, masses, mastalgia, firmness, asymmetry, migration, infection, and dimpling. We report the case of a 33-year-old woman who presented with distant migration of copolyamide breast filler to the left lower abdomen and inguinal area following mammography for breast cancer screening. This case highlights the potential risks associated with the migration of copolyamide breast fillers, particularly in the context of cancer screening procedures, and emphasizes the importance of awareness and vigilance among clinicians and patients.

Chemoembolization versus Radiotherapy for Single HepatocellularCarcinomas of ≤3 cm Unsuitable for Image-Guided Tumor Ablation

Background/Aims@#Local ablation therapy (LAT) is primarily recommended for solitary inoperable hepatocellular carcinomas (HCCs) of ≤3 cm in diameter. However, only two-thirds of uninod-ular small HCCs are suitable for LAT, and the second-best treatment option for managing these nodules is unclear. We aimed to compare the therapeutic outcomes of chemoembolization and radiotherapy in small HCCs unsuitable for LAT. @*Methods@#The study included 651 patients from a tertiary referral center who underwent planningsonography for LAT. These patients had 801 solitary HCCs of ≤3 cm in diameter and were treatedwith LAT, chemoembolization, or radiotherapy. Local tumor progression (LTP)-free survival and overall survival (OS) were measured according to the type of treatment of the index nodule. @*Results@#LAT, chemoembolization, and radiotherapy were used to treat 561, 185, and 55 nodules in 467, 148, and 36 patients, respectively. LTP-free survival was significantly shorter in patients treated with chemoembolization than for those treated with LAT (multivariate hazard ratio [HR], 2.36; 95% confidence interval [CI], 1.61 to 3.47) but not for those treated with radiotherapy (HR, 0.83; 95% CI, 0.38 to 1.83). However, OS was not affected by treatment modality. Matching and weighting analyses confirmed that radiotherapy gave comparable results to chemoembolization in terms of OS despite better LTP-free survival (HR, 2.91; 95% CI, 1.13 to 7.47 and HR, 3.07;95% CI, 1.11 to 8.48, respectively). @*Conclusions@#Our data suggest that chemoembolization and radiotherapy are equally effective options for single small HCCs found to be unsuitable for LAT after sonographic planning. Betterfit indications for each procedure should be established by specifically designed studies.

Axillary silicone lymphadenopathy caused by gel bleeding with intact silicone breast implants: a case report

Gel bleeding following breast augmentation using silicone breast implants (SBIs) occurs when microscopic silicone droplets diffuse through the implant surface, potentially resulting in complications such as capsular contracture and immune responses related to breast implant illness. Prompt and reliable diagnostic measures are crucial, as the presentation of gel bleeding can resemble cancer, making an accurate diagnosis challenging. This report discusses a rare case of axillary silicone lymphadenopathy caused by gel bleeding in a 48-year-old woman with intact SBIs. Silicone lymphadenopathy can be suspected based on mammography, ultrasonography, and magnetic resonance imaging in patients with a history of SBI insertion, and confirmation can be obtained through a pathological examination. Excisional biopsy is generally recommended for symptomatic patients, while treatment may not be necessary for asymptomatic patients; However, removal can be considered if the patient indicates a preference for it. Patients with silicone lymphadenopathy require replacement of SBIs to examine the breast capsule and verify the integrity of the implant. This case highlights the importance of considering gel bleeding as a potential cause of silicone lymphadenopathy, even in patients with intact SBIs.

Machine Learning Algorithms for the Prediction of Locomotor Activity by an Infrared Motion Detector on the Sleep-wake States in Mice

Objective@#Even though studies using machine learning on sleep-wake states have been performed, studies in various conditions are still necessary. This study aimed to examine the performance of the prediction model of locomotor activities on sleep-wake states using machine learning algorithms. @*Methods@#The processed data using moving average of locomotor activities were used as predicting features. The sleep-wake states were used as true labels. The prediction models were established by machine learning classifiers such as support vector machine with radial basis function (SVM-RBF), linear discriminant analysis (LDA), naïve Bayes, and random forest (RF). The prediction model was evaluated by a six-fold cross validation. @*Results@#The SVM-RBF and RF showed acceptable performance within a window of moving average from 480 to 1,200 seconds. The highest accuracy (0.869) was shown by the RF at the interval of 480 seconds. Meanwhile, the highest area under the curve (0.939) was shown by LDA at the interval of 870 seconds. @*Conclusion@#This study suggested that the prediction model on sleep-wake state using machine learning could show an improvement of the model performance when using moving average with raw data. The prediction model using locomotor activity can be useful in research on sleep-wake state.

SARS‑CoV‑2 Omicron variant causes brain infection with lymphoid depletion in a mouse COVID‑19 model / 한국실험동물학회지

Background@#The Omicron variant has become the most prevalent SARS-CoV-2 variant. Omicron is known to induce milder lesions compared to the original Wuhan strain. Fatal infection of the Wuhan strain into the brain has been well documented in COVID-19 mouse models and human COVID-19 cases, but apparent infections into the brain by Omicron have not been reported in human adult cases or animal models. In this study, we investigated whether Omicron could spread to the brain using K18-hACE2 mice susceptible to SARS-CoV-2 infection. @*Results@#K18-hACE2 mice were intranasally infected with 1 × 105 PFU of the original Wuhan strain and the Omicron variant of SARS-CoV-2. A follow-up was conducted 7 days post infection. All Wuhan-infected mice showed > 20% body weight loss, defined as the lethal condition, whereas two out of five Omicron-infected mice (40%) lost > 20% body weight. Histopathological analysis based on H&E staining revealed inflammatory responses in the brains of these two Omicron-infected mice. Immunostaining analysis of viral nucleocapsid protein revealed severe infection of neuron cells in the brains of these two Omicron-infected mice. Lymphoid depletion and apoptosis were observed in the spleen of Omicron-infected mice with brain infection. @*Conclusion@#Lethal conditions, such as severe body weight loss and encephalopathy, can occur in Omicron-infected K18-hACE2 mice. Our study reports, for the first time, that Omicron can induce brain infection with lymphoid depletion in the mouse COVID-19 model.

Chronic Hypoxemia Triggers a Neuropathic Process in Chronic Obstructive Pulmonary Disease:Insight From In Vivo Neurophysiological Assessments

Background@#and PurposePeripheral neuropathies (PNs) are a common but poorly understood complication of chronic obstructive pulmonary disease (COPD). To clarify the initial trigger of a PN in COPD, we investigated the excitability of peripheral nerves in patients with COPD. @*Methods@#The automated nerve excitability test (NET) using the threshold-tracking paradigm was applied to 20 COPD patients. The recording protocol calculated the strength–duration time constant, threshold electrotonus (TE), current–threshold relationship, and recovery cycle (RC). Each NET parameter was compared with two control groups: normal controls group (NC group) and smokers without COPD group (smoker group). @*Results@#In the motor NETs, the change in the threshold in the mid-depolarizing phase of TE (40–60 ms) was smaller in the COPD group (50.7%±1.2%, mean±SEM; n=20) than in the NC group (54.5%±0.7%, n=25; p<0.01), as was the prominence of superexcitability in the RC (-22.6%±1.5% and -26.4%±1.1%, respectively; p=0.04). There were no significant differences in the sensory NETs. Comparisons between the COPD and smoker groups (n=25) also showed no differences in either the motor or sensory NETs. @*Conclusions@#The pattern of excitability in COPD revealed a membrane depolarization attributable to Na+–K+–ATPase failure in the axolemma of distal motor nerves. This finding suggests that chronic hypoxemia and adaptative process can alter axonal excitability and trigger a resultant neuropathic process that is antecedent to PN in COPD.

Subclassification of advanced-stage hepatocellular carcinoma with macrovascular invasion: combined transarterial chemoembolization and radiotherapy as an alternative first-line treatment

Background@#/Aim: The Barcelona Clinic Liver Cancer (BCLC) guidelines recommend systemic therapy as the only first-line treatment for patients with BCLC stage C hepatocellular carcinoma (HCC) despite its heterogeneity of disease extent. We aimed to identify patients who might benefit from combined transarterial chemoembolization (TACE) and radiation therapy (RT) by subclassifying BCLC stage C. @*Methods@#A total of 1,419 treatment-naïve BCLC stage C patients with macrovascular invasion (MVI) who were treated with combined TACE and RT (n=1,115) or systemic treatment (n=304) were analyzed. The primary outcome was overall survival (OS). Factors associated with OS were identified and assigned points by the Cox model. The patients were subclassified into three groups based on these points. @*Results@#The mean age was 55.4 years, and 87.8% were male. The median OS was 8.3 months. Multivariate analysis revealed a significant association of Child-Pugh B, infiltrative-type tumor or tumor size ≥10 cm, main or bilateral portal vein invasion, and extrahepatic metastasis with poor OS. The sub-classification was categorized into low (point ≤1), intermediate (point=2), and high (point ≥3) risks based on the sum of points (range, 0–4). The OS in the low, intermediate, and high-risk groups was 22.6, 8.2, and 3.8 months, respectively. In the low and intermediate-risk groups, patients treated with combined TACE and RT exhibited significantly longer OS (24.2 and 9.5 months, respectively) than those who received systemic treatment (6.4 and 5.1 months, respectively; P<0.0001). @*Conclusions@#Combined TACE and RT may be considered as a first-line treatment option for HCC patients with MVI when classified into low- and intermediate-risk groups.

The Effect of Long-Term Care Ratings and Benefit Utilization Characteristics on Healthcare Use / 보건행정학회지

Background@#The long-term care (LTC) group has higher rates of chronic disease and disability registration compared to the general older people population. There is a need to provide integrated medical services and care for LTC group. Consequently, this study aimed to identify medical usage patterns based on the ratings of LTC and the characteristics of benefits usage in the LTC group. @*Methods@#This study employed the National Health Insurance Service Database to analyze the effects of demographic and LTC-related characteristics on medical usage from 2015 to 2019 using a repeated measures analysis. A longitudinal logit model was applied to binary data, while a linear mixed model was utilized for continuous data. @*Results@#In the case of LTC ratings, a positive correlation was observed with overall medical usage. In terms of LTC benefit usage characteristics, a higher overall level of medical usage was found in the group using home care benefits. Detailed analysis by medical institution classification revealed a maintained correlation between care ratings and the volume of medical usage. However, medical usage by classification varied based on the characteristics of LTC benefit usage. @*Conclusion@#This study identified a complex interaction between LTC characteristics and medical usage. Predicting the requisite medical services based on the LTC rating presented a challenge. Consequently, it becomes essential for the LTC group to continuously monitor medical and care needs, even after admission into the LTC system. To facilitate this, it is crucial to devise an LTC rating system that accurately reflects medical needs and to broaden the implementation of integrated medical-care policies.

The Effects of the Infant Health Promotion Program for Mothers with Their Firstborn Infants

Purpose@#This study was intended to evaluate the effects of an Infant Health Promotion Program (IHPP) for mothers with their firstborn infants. @*Methods@#This study employed a non-equivalent control group pretest-posttest design. The participants consisted of 17 mothers with their firstborn infants in the experimental group and 17 in the control group from two women’s hospitals. The experimental group received eight sessions of the program for four weeks. The collected data were analyzed using the chi-square test and repeated-measures ANOVA using an SPSS/WIN ver. 22.0. @*Results@#The experimental group receiving the program had statistically significant higher levels of infant health promotion knowledge (F = 22.91, p < .001), social support (F = 27.64, p < .001), maternal role confidence (F = 8.25, p = .005) and health promotion behavior for infants (F = 16.85, p < .001) than the control group. The experimental group had a statistically significant lower level of parenting stress than the control group (F = 29.93, p < .001). @*Conclusion@#The study’s findings indicate that the IHPP is effective in improving health promotion knowledge, social support, and maternal role confidence and decreasing parenting stress among mothers with their firstborn infants. A method of delivering intervention, focused on readily accessible online platforms, coupled with intervention strategies grounded in the theory of self-efficacy, proves to be an advantageous approach for this particular target group.

Understanding Atelocollagen Injections for Patients with Foot and Ankle Diseases / 대한족부족관절학회지

Collagen is the most common structural protein in the connective tissues of vertebrates, playing a crucial role in maintaining the tissue structure and wound healing. Atelocollagen retains the original properties of collagen but does not induce inflammatory cytokines. Atelocollagen is extracted from various animals and humans, with bovine-derived collagen being the most commonly used. The safety and efficacy of atelocollagen have been demonstrated through multiple studies, but further research will be needed in the field of orthopedics regarding its range of use and effects. Foot and ankle diseases have attracted little research attention, highlighting the need for further studies.

Melatonin Protects Chronic Kidney Disease Mesenchymal Stem/Stromal Cells against Accumulation of Methylglyoxal via Modulation of Hexokinase-2 Expression

Treatment options for patients with chronic kidney disease (CKD) are currently limited; therefore, there has been significant interest in applying mesenchymal stem/stromal cell (MSC)-based therapy to treat CKD. However, MSCs harvested from CKD patients tend to show diminished viability and proliferation due to sustained exposure to uremic toxins in the CKD environment, which limits their utility for cell therapy. The application of melatonin has been demonstrated to improve the therapeutic efficacy of MSCs derived from and engrafted to tissues in patients suffering from CKD, although the underlying biological mechanism has not been elucidated. In this study, we observed overexpression of hexokinase-2 (HK2) in serum samples of CKD patients and MSCs harvested from an adenine-fed CKD mouse model (CKD-mMSCs). HK2 upregulation led to increased production levels of methylglyoxal (MG), a toxic metabolic intermediate of abnormal glycolytic processes. The overabundance of HK2 and MG was associated with impaired mitochondrial function and low cell proliferation in CKD-mMSCs. Melatonin treatment inhibited the increases in HK2 and MG levels, and further improved mitochondrial function, glycolytic metabolism, and cell proliferation. Our findings suggest that identifying and characterizing metabolic regulators such as HK2 in CKD may improve the efficacy of MSCs for treating CKD and other kidney disorders.

Delta neutrophil index as a predictor of vesicoureteral reflux in children with febrile urinary tract infection

Purpose@#Delta neutrophil index (DNI) indicates immature granulocytes in peripheral blood and has been confirmed to be effective as a prognostic factor for neonatal sepsis. Also, it has been reported to have diagnostic value in acute pyelonephritis and in predicting vesicoureteral reflux (VUR) in the infant. We conducted the study to verify whether DNI is also helpful in the entire pediatric age group with febrile urinary tract infection (UTI). @*Methods@#Medical records of children hospitalized for febrile UTIs were analyzed retrospectively. All subjects underwent kidney ultrasound and voiding cystourethrography. In the group with and without VUR, we compared sex and age, and the following laboratory values: the white blood cell count, neutrophil, polymorphonuclear leucocyte, eosinophil, hemoglobin, platelet count, C-reactive protein, DNI value, and the finding of ultrasound. @*Results@#A total of 315 patients (163 males and 152 females; range, 0–127 months) were eligible, and 41 patients (13%) had VUR. As a result of univariate analysis, the white blood cell count, neutrophil, DNI, and ultrasonic abnormalities were high in the reflux group, and the hemoglobin and lymphocyte fraction values were low. The value of DNI and the abnormal ultrasound were significantly higher in the reflux group on the multivariate analysis. The area under the curve value of the receiver operating curve was higher in DNI (0.640; 95% confidence interval, 0.536–0.744; P=0.004), and the DNI cutoff value for VUR prediction was 1.85%. @*Conclusions@#We identified that ultrasound findings and DNI values were helpful predictors of VUR in pediatric febrile UTIs.

Saccharomyces boulardii and Lactulose for Childhood Functional Constipation: A Multicenter Randomized Controlled Trial

Background/Aims@#The effects of probiotics in children vary based on diseases and probiotic strains. We aim to investigate the effectiveness of Saccharomyces boulardii and lactulose for treating childhood functional constipation. @*Methods@#This open-label randomized controlled trial was conducted at 10 university hospitals in Korea. Children who were diagnosed with functional constipation were allocated to 3 groups (lactulose monotherapy, combination therapy, and S. boulardii monotherapy). The primary outcome was treatment success rate that was accordingly defined as ≥ 3 bowel movements without incontinence at week 12. The cumulative successful maintenance and drug maintenance rates without drug changes were calculated throughout the study period. We compared stool frequency, incontinence, consistency, and painful defecation at week 2 among the 3 groups. @*Results@#Overall, 187 children were assigned to the lactulose monotherapy (n = 69), combination therapy (n = 68), or S. boulardii monotherapy (n = 50) groups. The primary outcome was significantly higher in the lactulose monotherapy group (26.1%) or combination therapy group (41.2%) than in the S. boulardii monotherapy group (8.0%). The S. boulardii monotherapy group showed a significantly lower cumulative successful maintenance and drug maintenance rate than the other 2 groups. There were no significant intergroup differences in the frequency of defecation, incontinence, painful defecation, or stool consistency during the follow-up at week 2. @*Conclusion@#S. boulardii monotherapy was not superior to lactulose monotherapy or combination therapy and showed a higher drug change rate, supporting the current recommendation of probiotics in the treatment of childhood functional constipation.

Analysis of ultradian rest-activity rhythms using locomotor activity in mice / 고신대학교의과대학학술지

Background@#Locomotor activity in mice may have an ultradian rest-activity rhythm. However, to date, no study has shown how locomotor activity can be explained statistically using fitted cosine curves. Therefore, this study explored whether the ultradian rhythm of locomotor activity in mice could be analyzed using cosine fitting analysis. @*Methods@#The locomotor activity of 20 male mice under a 12/12-hour dark/light cycle for 2 days was fitted to a cosine function to obtain the best fit. The mean absolute error (MAE) values were used to determine the explanatory power of the calculated cosine model for locomotor activity. The cosine fitting analysis was performed using R statistical software (version 4.1.1). @*Results@#The mean MAE was 0.2944, whereas the mean MAE for integrating the individual analyses in the two experimental groups was 0.3284. The periods of the estimated ultradian rest-activity rhythm ranged from 1.602 to 4.168 hours. @*Conclusions@#These results suggest that locomotor activity data reflect an ultradian rhythm better than a circadian rhythm. Locomotor activity can be statistically fitted to a cosine curve under well-controlled conditions. In the future, it will be necessary to explore whether this cosine-fitting analysis can be used to analyze ultradian rhythms under different experimental conditions.

Correlation between Transient Elastography (Fibroscan ® ) and Ultrasonographic and Computed Tomographic Grading in Pediatric Nonalcoholic Steatohepatitis / 대한소아소화기영양학회지

Purpose@#This study aimed to examine the advantages and usefulness of transient elastography (Fibroscan ® ) in diagnosing non-alcoholic steatohepatitis in children and adolescents compared to those of abdominal computed tomography and liver ultrasonography. @*Methods@#Forty-six children and adolescent participants aged between 6 and 16 years who underwent transient elastography (Fibroscan ® ) as well as liver ultrasonography or abdominal computed tomography were included. Thirty-nine participants underwent liver ultrasonography and 11 underwent computed tomography. The physical measurements, blood test results, presence of metabolic syndrome, and the degree of liver steatosis and liver fibrosis were analyzed, and their correlations with transient elastography (Fibroscan ® ), abdominal computed tomography, and liver ultrasonography, as well as the correlations between examinations, were analyzed. @*Results@#Thirty-six participants (78.3%) were boys, and the mean age was 12.29±2.57 years, with a mean body mass index of 27.88±4.28. In the 46 participants, the mean values for aspartate aminotransferase, alanine aminotransferase, and total bilirubin were 89.87±118.69 IU/L, 138.54±141.79 IU/L, and 0.77±0.61 mg/dL, respectively. Although transient elastography (Fibroscan ® ) and abdominal computed tomography grading had a statistically significant positive correlation with aspartate aminotransferase and alanine aminotransferase values, the correlations between the results of grading performed by transient elastography (Fibroscan ® ), abdominal computed tomography, and liver ultrasonography were not statistically. @*Conclusion@#We confirmed that each examination was correlated with the results of some blood tests, suggesting the usefulness and possibility of diagnosis and treatment of steatohepatitis mediated by transient elastography (Fibroscan ® ) in the department of pediatrics.

Optimization of Analysis of Circadian Rest-Activity Rhythm Using Cosinor Analysis in Mice

Objective@#Data processing in analysis of circadian rhythm was performed in various ways. However, there was a lack of evidence for the optimal analysis of circadian rest-activity rhythm. Therefore, we aimed to perform mathematical simulations of data processing to investigate proper evidence for the optimal analysis of circadian rest-activity rhythm. @*Methods@#Locomotor activities of 20 ICR male mice were measured by infrared motion detectors. The data of locomotor activities was processed using data summation, data average, and data moving average methods for cosinor analysis. Circadian indices were estimated according to time block, respectively. Also, statistical F and p-values were calculated by zero-amplitude test. @*Results@#The data moving average result showed well-fitted cosine curves independent of data processing time. Meanwhile, the amplitude, MESOR, and acrophase were properly estimated within 800 seconds in data summation and data average methods. @*Conclusion@#These findings suggest that data moving average would be an optimal method for data processing in a cosinor analysis and data average within 800-second data processing time might be adaptable. The results of this study can be helpful to analyze circadian restactivity rhythms and integrate the results of the studies using different data processing methods.

A comparative discussion of incisional methods in total capsulectomy of the breast

Background@#Capsular contracture is a frequent complication of breast augmentation that constitutes one of the most common reasons for secondary operations. Capsular contracture is treated surgically, often with total capsulectomy. Therefore, in this study, we aimed to study correlations among intraoperative observations, physical examination findings, and characteristics of the previous operation in patients with capsular contracture who underwent total capsulectomy. @*Methods@#A retrospective chart review was conducted for patients treated from May 2017 to April 2019, analyzing 24 breasts in 12 female patients. The patients were classified in terms of the Baker grade, incision type, implant type, and implant plane. During the operation, we evaluated the ease of dissection based on intraoperative features such as anterior and posterior wall dissection, bleeding tendency, and scar length. Statistical analysis was performed to identify association between variables @*Results@#The implant was changed in eight patients, while only explantation was performed in the remaining four patients. The ease of capsule dissection had a proportional correlation with the Baker grade (P=0.005). Intraoperative dissection was significantly easier in the inframammary fold (IMF) group than in the periareolar group (P=0.035). @*Conclusions@#An IMF incision is preferable for planning en bloc capsulectomy. However, for aesthetic concerns, a periareolar incision would be preferable. In addition, a lower Baker grade (grade I or II) was associated with easier dissection. Therefore, surgeons should choose the incision type depending on the necessity of performing en bloc capsulectomy, Baker grade, and scar length.

Contributing Factors of Excessive Daytime Sleepiness in Morbid Obese Patients with Obstructive Sleep Apnea

Background@#Obesity, obstructive sleep apnea (OSA), and excessive daytime sleepiness (EDS) are common conditions and are interrelated. Obesity is a risk factor for OSA and independently associated with EDS. We aimed to evaluate frequency of EDS in morbid obese patients with OSA and to identify contribution factor for EDS. @*Methods@#This was a retrospective cross-sectional study in single sleep center. Consecutive patients with OSA (with apnea-hypopnea index 5/h or more) with morbid obesity (body mass index over 35 kg/m2) was enrolled. EDS were defined as Epworth Sleepiness Scale of 10 points or more. Clinical and polysomnographic variables were compared between those with and without EDS. @*Results@#Total 110 morbid obese patients with OSA were enrolled, and 34 (31%) of them had EDS. Those with EDS had higher subjective symptom of insomnia and depression. Rapid eye movement sleep latency was shorter and minimum saturation was lower for those with EDS. Multivariate logistic regression analysis identified insomnia severity (odds ratio, 1.117) and minimum saturation (odds ratio, 0.952) as independent contribution factor for EDS. @*Conclusions@#Result of this study suggest that 31.4% of morbid obese patients with OSA have EDS, and it can be affected by insomnia severity and desaturation during sleep.

Usefulness of Kaloderm® in Finger Tip Necrosis : A Case Report / 고신대학교의과대학학술지

We experienced a case of crush injury of the hand for which we performed a flap surgery and treated the necrotic parts placement using cultured allogeneic keratinocytes (Kaloderm® ) with good results. The patient was a 31-year-old woman whose left middle finger was caught in a door, causing a crush injury. Although primary repair was performed, a 2 × 2.5-cm-sized necrosis developed, and a V-Y advancement flap was performed after the removal of dead tissues. However, a 1 × 2-cm-sized partial necrosis occurred and was treated using Kaloderm ® . After the use of Kaloderm® , the patient’s wound was healed, and no complications, except for mild pain, were observed for 1 year after the surgery. If a necrotic site appears after flap placement of fingertip, its treatment is difficult. If used well, Kaloderm® may be a good option for necrosis of the fingertips and other areas that are difficult to cure.

Evaluation of methods for fitness of removable partial denture / 北京大学学报(医学版)

OBJECTIVE@#To compare the differences and indications of three evaluation methods for fitness evaluation of removable partial denture (RPD).@*METHODS@#A RPD was fabricated and seated on the stone cast of a partially edentulous mandible, and the spaces between RPD and stone cast were recorded with polyvinyl siloxane (PVS) impression material forming PVS replicas. Using cross sectional measurement, the average thicknesses of PVS replicas were measured under stereomicroscope with different numbers of selected measuring points in the denture base, major connector, occlusal rest of the RPD, and the average thicknesses of the PVS replicas measured with different numbers of measuring points were compared using one-way analysis of variance (ANOVA) and independent sample t test. Three kinds of method, including cross sectional measurement, three-dimensional analysis on the stone cast, and three-dimensional analysis on the polyether cast, were applied to measure the average thicknesses of the PVS replicas, and the average thicknesses of the PVS replicas measured by these three evaluation methods were compared with ANOVA.@*RESULTS@#For cross sectional measurement, statistically significant differences were found in the average thicknesses of the PVS replicas in the denture base and the major connector among the different numbers of measuring points (P < 0.05), but no differences were found in the average thicknesses of the PVS replicas in the occlusal rest (P>0.05). There were significant differences among the average thicknesses of the PVS replicas measured by these three evaluation methods in each component of the RPD (P < 0.01). The average thickness measured by three-dimensional analysis on the stone cast and three-dimensional analysis on polyether cast were smaller than that measured by cross sectional measurement (P < 0.05). And there were no differences between the average thicknesses of PVS replicas measured by three-dimensional analysis on stone cast and three-dimensional analysis on polyether cast (P>0.05).@*CONCLUSION@#For cross sectional measurement, the average thickness of the PVS replicas was influenced by the number of measuring points, and the measurement accuracy of cross sectional measurement was not reliable enough. Three-dimensional analysis on stone cast which is suitable for evaluation in vitro and three-dimensional analysis on polyether cast which is suitable for evaluation in vivo can evaluate the fitness of RPD more comprehensively and effectively than that of cross sectional measurement.