Background: This study aimed to analyze the accuracy of the output of three-dimensional (3D) customized surgical guides and titanium implants in a rabbit model, and of mandibulectomy, reconstructive surgery, and surgical outcome; additionally, the correlation between surgical accuracy and surgical outcomes, including the differences in surgical outcome according to surgical accuracy, was analyzed. Results: The output of implants was accurately implemented within the error range (− 0.03–0.03 mm), and the surgical accuracy varied depending on the measured area (range − 0.4–1.1 mm). Regarding surgical outcomes, anglebetween the mandibular lower borders showed the most sensitive results and distance between the lingual cusps of the first molars represented the most accurate outcomes. A significant correlation was noted between surgical accuracy in the anteroposterior length of the upper borders pre- and postoperatively and the angle between themandibular lower borders (regression coefficient = 0.491, p = 0.028). In the group wherein surgery was performed more accurately, the angle between the mandibular lower borders was reproduced more accurately (p = 0.021). Aselective laser melting machine accurately printed the implants as designed. Considering the positive correlation among surgical accuracy in the mandibular upper borders, angle between the mandibular lower borders, and more accurately reproduced angle between the mandibular lower borders, the angle between the mandibular lower borders is considered a good indicator for evaluating the outcomes of reconstructive surgery. Conclusion To reduce errors in surgical outcomes, it is necessary to devise a positioner for the surgical guide and design a 3D surgical guide to constantly maintain the direction of bone resection. A fixed area considering the concept of three-point fixation should be selected for stable positioning of the implant; in some cases, bilateral cortical bone fixation should be considered. The angle between the mandibular lower borders is a sensitive indicator for evaluating the outcomes of reconstructive surgery.

no abstract available.

Background: The use of cosmeceuticals, cosmetics that are medically proven to improve certain skin qualities, has been generalized to the public. While they were invented to selectively enhance targeted biophysical skin qualities, product selection is highly dependent on subjective perceptions rather than objective assessments. Objective: To evaluate whether subjective perceptions can accurately characterize one’s skin condition, especially in the Korean population, which shows a high interest in cosmetics and skin conditions. Methods: Biophysical parameter measurements were obtained from the 2018 International Skin Characteristics Data Bank Project conducted by the Foundation of the Korea Cosmetic Industry Institute. Participants were 220 healthy South Korean adults. Each participant was asked to evaluate their own skin type in terms of sensitivity, hydration, oiliness, roughness, and thickness. The same subjects were objectively examined using bioengineering devices for the related biophysical parameters. Significance was evaluated using the chi-squared test. Results: Oiliness showed a significant correlation between subjective and objective skin assessments. Although sensitivity, hydration, roughness, and thickness showed positive relationships, none were statistically significant. Interestingly, self-perceived skin texture was highly dependent on pore-induced bumpiness rather than intricate skin surface topology. Also, uneven skin texture tended to be perceived as thick skin. Conclusion Subjectively assessed skin types may limit the precise characterization of the skin’s properties. Therefore, biophysical measurements should be used to assess skin types, particularly with regard to sensitivity, hydration, roughness, and thickness. This Korean population showed no superiority at perceiving skin types compared to subjects of previous studies.

In preparation for the surge of coronavirus disease 2019 (COVID-19), it is crucial to allocate medical resources efficiently for distinguishing people who remain asymptomatic until the end of the disease. Between January 27, 2020, and April 21, 2020, 517 COVID-19 cases from 13 healthcare facilities in Gyeonggi province, Korea, were identified out of which the epidemiologic and clinical information of 66 asymptomatic patients at the time of diagnosis were analyzed retrospectively. An exposure-diagnosis interval within 7 days and abnormal aspartate aminotransferase levels were identified as characteristic symptom development in asymptomatic COVID-19 patients. If asymptomatic patients without these characteristics at the time of diagnosis could be differentiated early, more medical resources could be secured for mild or moderate cases in this COVID-19 surge.

Background: We analyzed cell-free serum Epstein‒Barr virus (EBV) DNA to identify its prognostic role in patients with newly diagnosed lymphoma. Methods: We retrospectively reviewed patients diagnosed with lymphoma between January 2014 and July 2020. Patients were enrolled according to the following criteria: i) pathologically confirmed lymphomas according to the World Health Organization criteria, ii) age over 18 years, iii) serum EBV DNA measurement using polymerase chain reaction prior to first-line therapy, and iv) receipt of curative standard chemotherapy. In total, 263 patients met these criteria and were included in this study. Results: Serum EBV DNA was detected in 79 patients (30.0%). Patients with positive serum EBV tended to be older (P =0.090), and the proportion of T-cell lineage lymphomas was higher than that of B-cell lymphomas (P =0.003). EBV positivity was significantly associated with more advanced disease based on the Ann Arbor staging system (P =0.008) and the International Prognostic Index (P =0.009). EBV positivity was also associated with higher disease relapse (P =0.038) and death rates (P =0.005). EBV-positive lymphomas further showed inferior long-term survival outcomes in terms of progression-free survival (PFS) (P =0.053) and overall survival (OS) (P =0.014). In the subgroup analyses, serum EBV positivity was a significant prognostic factor for patients with B-cell lineage lymphomas in terms of PFS (P =0.003) and OS (P =0.033). Conclusion We demonstrated that cell-free serum EBV DNA status at the time of diagnosis has potential as a prognostic biomarker for patients with newly diagnosed malignant lymphomas.

Background: We analyzed cell-free serum Epstein‒Barr virus (EBV) DNA to identify its prognostic role in patients with newly diagnosed lymphoma. Methods: We retrospectively reviewed patients diagnosed with lymphoma between January 2014 and July 2020. Patients were enrolled according to the following criteria: i) pathologically confirmed lymphomas according to the World Health Organization criteria, ii) age over 18 years, iii) serum EBV DNA measurement using polymerase chain reaction prior to first-line therapy, and iv) receipt of curative standard chemotherapy. In total, 263 patients met these criteria and were included in this study. Results: Serum EBV DNA was detected in 79 patients (30.0%). Patients with positive serum EBV tended to be older (P =0.090), and the proportion of T-cell lineage lymphomas was higher than that of B-cell lymphomas (P =0.003). EBV positivity was significantly associated with more advanced disease based on the Ann Arbor staging system (P =0.008) and the International Prognostic Index (P =0.009). EBV positivity was also associated with higher disease relapse (P =0.038) and death rates (P =0.005). EBV-positive lymphomas further showed inferior long-term survival outcomes in terms of progression-free survival (PFS) (P =0.053) and overall survival (OS) (P =0.014). In the subgroup analyses, serum EBV positivity was a significant prognostic factor for patients with B-cell lineage lymphomas in terms of PFS (P =0.003) and OS (P =0.033). Conclusion We demonstrated that cell-free serum EBV DNA status at the time of diagnosis has potential as a prognostic biomarker for patients with newly diagnosed malignant lymphomas.

Recently, the number of patients with coronavirus disease 2019 (COVID-19) who have tested positive for severe acute respiratory syndrome coronavirus 2 (SARSCoV-2), via the reverse transcription polymerase chain reaction (RT-PCR) test, after recovery has increased; this has caused a dilemma regarding the medical measures and policies. We evaluated the dynamics of viral load and anti-SARSCoV-2 antibodies in four patients with positive RT-PCR results after recovery. In all patients, the highest levels of immunoglobulin G (IgG) and IgM antibodies were reached after about a month of the onset of the initial symptoms. Then, the IgG titers plateaued, and the IgM titers decreased, regardless of RT-PCR results.The IgG and IgM levels did not increase after the post-negative positive RT-PCR results in any of the patients. Our results reinforced that the post-negative positive RT-PCR results may be due to the detection of RNA particles rather than reinfection in individuals who have recovered from COVID-19.