1.Reconstruction of hand.
Kyungjin LEE ; Dongchul LEE ; Siyoung ROH ; Jinsoo KIM
Journal of the Korean Medical Association 2016;59(2):127-135
The characteristics of hand trauma are changing due to automation of industrial facilities, improved access to health care, and the aging population. Since the inception of hand surgery as a subspecialty, hand defects have been reconstructed with the restoration of the original functionality as the primary goal. With advancement and maturation of surgical techniques, however, restoration of aesthetics also began to take hold as an important aspect of hand surgery practice. After the first successful replantation of an amputated digit, the rapid development of microsurgical techniques had a significant impact on the field of reconstructive hand surgery. In the first two decades, the success of replantation was evaluated by the survival rate for a single operator or a specialized institution. These days, however, microsurgical techniques have been widely adopted, with digital replantation possible even for infants. In addition to various local flaps, the evolution of free flaps has vastly expanded the repertoire of reconstructive options for hand surgeons. With the wide variety of free flaps available, it is possible for a severely injured hand to be salvaged and restored to its original functional and aesthetic status. In South Korea, hand surgery is becoming an established profession with a separate subspecialty certification. Hand surgery has a bright outlook, with future research directed at new biocompatible materials and novel reconstructive methods.
Aging
;
Automation
;
Biocompatible Materials
;
Certification
;
Esthetics
;
Free Tissue Flaps
;
Hand*
;
Health Services Accessibility
;
Humans
;
Infant
;
Korea
;
Microsurgery
;
Replantation
;
Survival Rate
2.Study of Bacteria Associated with Dental Caries Using a 3 Tone Disclosing Agent
Jeongeun LEE ; Howon PARK ; Juhyun LEE ; Hyunwoo SEO ; Siyoung LEE
Journal of Korean Academy of Pediatric Dentistry 2018;45(1):32-40
The aim of this study was to determine the efficacy of a 3 tone plaque disclosing gel in assessing the risk of caries related to the population of Streptococcus mutans, Streptococcus sobrinus, and Lactobacillus spp. quantified using a quantitative real-time polymerase chain reaction (qRT-PCR).15 healthy children of ages 9 – 12 years were randomly examined. The 3 tone plaque disclosing gel was applied on teeth surfaces, which changed the color to pink or red, blue or purple and light blue. Plaque was divided into 3 groups based on staining. Genomic DNA from each sample was subjected to a qRT-PCR assay for quantitative detection of target bacteria. The Kruskal-Wallis test was conducted for correlation between the color of plaque and the number of bacterial species.The levels of S. mutans, S. sobrinus, and Lactobacillus spp. were significantly different in the plaque samples of the 3 groups (p < 0.05). The proportion of S. sobrinus to S. mutans showed correlation to the color of plaque.The different color-dyed plaque was related to the number of acidogenic bacteria. The 3 tone plaque disclosing gel could be used as one of the indicators to assess the clinical risk of caries associated with the population of S. mutans, S. sobrinus, and Lactobacillus spp.
Bacteria
;
Child
;
Dental Caries
;
Dental Plaque
;
DNA
;
Humans
;
Lactobacillus
;
Real-Time Polymerase Chain Reaction
;
Streptococcus mutans
;
Streptococcus sobrinus
;
Tooth
3.Potential of Erythrosine-Mediated Photodynamic Therapy as a Cavity Disinfectant: Antibacterial Efficacy and Bonding Ability
Gawon LEE ; Haeni KIM ; Siyoung LEE ; Juhyun LEE
Journal of Korean Academy of Pediatric Dentistry 2024;51(3):290-298
This study aimed to evaluate the antibacterial efficacy of erythrosine-mediated photodynamic therapy (PDT) against Streptococcus mutans (S. mutans) in dentin and its effect on the shear bond strength (SBS) of composite resin to dentin. Eighty extracted human noncarious premolars were used in this study. Forty teeth were used for the antibacterial activity test, while the remaining 40 were used for the SBS test. Both experiments were conducted with 4 experimental groups (n = 10): control (distilled water), sodium hypochlorite (NaOCl, 6%), chlorhexidine (CHX, 0.12%), and erythrosine-mediated PDT. Antibacterial effects were evaluated by counting S. mutans colony-forming units (CFUs). The SBS of composite resins to dentin was measured using a universal testing machine. All treatments (NaOCl, CHX, and PDT) demonstrated statistically significant differences in antibacterial activity compared with the control group (p < 0.05). The antibacterial effects were ranked from strongest to weakest as follows: NaOCl, PDT, and CHX. In the SBS test, the NaOCl group exhibited a statistically significant difference compared with the CHX, PDT, and control groups (p < 0.05), with the lowest bond strength. No statistically significant differences were found among the CHX, PDT, and control groups (p > 0.05). Erythrosine-mediated PDT exhibited significant antibacterial effects against S. mutans, with higher antibacterial activity than CHX but lower than NaOCl. Only NaOCl negatively affected the bond strength of composite resin to dentin. In conclusion, erythrosine-mediated PDT shows potential as a cavity disinfectant due to its significant antibacterial effects against S. mutans and lack of adverse effects on bond strength.
4.Potential of Erythrosine-Mediated Photodynamic Therapy as a Cavity Disinfectant: Antibacterial Efficacy and Bonding Ability
Gawon LEE ; Haeni KIM ; Siyoung LEE ; Juhyun LEE
Journal of Korean Academy of Pediatric Dentistry 2024;51(3):290-298
This study aimed to evaluate the antibacterial efficacy of erythrosine-mediated photodynamic therapy (PDT) against Streptococcus mutans (S. mutans) in dentin and its effect on the shear bond strength (SBS) of composite resin to dentin. Eighty extracted human noncarious premolars were used in this study. Forty teeth were used for the antibacterial activity test, while the remaining 40 were used for the SBS test. Both experiments were conducted with 4 experimental groups (n = 10): control (distilled water), sodium hypochlorite (NaOCl, 6%), chlorhexidine (CHX, 0.12%), and erythrosine-mediated PDT. Antibacterial effects were evaluated by counting S. mutans colony-forming units (CFUs). The SBS of composite resins to dentin was measured using a universal testing machine. All treatments (NaOCl, CHX, and PDT) demonstrated statistically significant differences in antibacterial activity compared with the control group (p < 0.05). The antibacterial effects were ranked from strongest to weakest as follows: NaOCl, PDT, and CHX. In the SBS test, the NaOCl group exhibited a statistically significant difference compared with the CHX, PDT, and control groups (p < 0.05), with the lowest bond strength. No statistically significant differences were found among the CHX, PDT, and control groups (p > 0.05). Erythrosine-mediated PDT exhibited significant antibacterial effects against S. mutans, with higher antibacterial activity than CHX but lower than NaOCl. Only NaOCl negatively affected the bond strength of composite resin to dentin. In conclusion, erythrosine-mediated PDT shows potential as a cavity disinfectant due to its significant antibacterial effects against S. mutans and lack of adverse effects on bond strength.
5.Potential of Erythrosine-Mediated Photodynamic Therapy as a Cavity Disinfectant: Antibacterial Efficacy and Bonding Ability
Gawon LEE ; Haeni KIM ; Siyoung LEE ; Juhyun LEE
Journal of Korean Academy of Pediatric Dentistry 2024;51(3):290-298
This study aimed to evaluate the antibacterial efficacy of erythrosine-mediated photodynamic therapy (PDT) against Streptococcus mutans (S. mutans) in dentin and its effect on the shear bond strength (SBS) of composite resin to dentin. Eighty extracted human noncarious premolars were used in this study. Forty teeth were used for the antibacterial activity test, while the remaining 40 were used for the SBS test. Both experiments were conducted with 4 experimental groups (n = 10): control (distilled water), sodium hypochlorite (NaOCl, 6%), chlorhexidine (CHX, 0.12%), and erythrosine-mediated PDT. Antibacterial effects were evaluated by counting S. mutans colony-forming units (CFUs). The SBS of composite resins to dentin was measured using a universal testing machine. All treatments (NaOCl, CHX, and PDT) demonstrated statistically significant differences in antibacterial activity compared with the control group (p < 0.05). The antibacterial effects were ranked from strongest to weakest as follows: NaOCl, PDT, and CHX. In the SBS test, the NaOCl group exhibited a statistically significant difference compared with the CHX, PDT, and control groups (p < 0.05), with the lowest bond strength. No statistically significant differences were found among the CHX, PDT, and control groups (p > 0.05). Erythrosine-mediated PDT exhibited significant antibacterial effects against S. mutans, with higher antibacterial activity than CHX but lower than NaOCl. Only NaOCl negatively affected the bond strength of composite resin to dentin. In conclusion, erythrosine-mediated PDT shows potential as a cavity disinfectant due to its significant antibacterial effects against S. mutans and lack of adverse effects on bond strength.
6.Effect of Sub-minimal Inhibitory Concentration of Chlorhexidine on Biofilm Formation and Coaggregation of Early Colonizers, Streptococci and Actinomycetes.
International Journal of Oral Biology 2016;41(4):209-215
Chlorhexidine has long been used in mouth washes for the control of dental caries, gingivitis and dental plaque. Minimal inhibitory concentration (MIC) is the lowest concentration of an antimicrobial substance to inhibit the growth of bacteria. Concentrations lower than the MIC are called sub minimal inhibitory concentrations (sub-MICs). Many studies have reported that sub-MICs of antimicrobial substances can affect the virulence of bacteria. The aim of this study was to investigate the effect of sub-MIC chlorhexidine on biofilm formation and coaggregation of oral early colonizers, such as Streptococcus gordonii, Actinomyces naeslundii and Actinomyces odontolyticus. The biofilm formation of S. gordonii, A. naeslundii and A. odontolyticus was not affected by sub-MIC chlorhexidine. However, the biofilm formation of S. mutans increased after incubation with sub-MIC chlorhexidine. In addition, cell surface hydrophobicity of S. mutans treated with sub-MIC of chlorhexidine, decreased when compared with the group not treated with chlorhexidine. However, significant differences were seen with other bacteria. Coaggregation of A. naeslundii with A. odontolyticus reduced by sub-MIC chlorhexidine, whereas the coaggreagation of A. naeslundii with S. gordonii remained unaffected. These results indicate that sub-MIC chlorhexidine could influence the binding properties, such as biofilm formation, hydrophobicity and coaggregation, in early colonizing streptococci and actinomycetes.
Actinobacteria*
;
Actinomyces
;
Bacteria
;
Biofilms*
;
Chlorhexidine*
;
Colon*
;
Dental Caries
;
Dental Plaque
;
Gingivitis
;
Hydrophobic and Hydrophilic Interactions
;
Mouth
;
Streptococcus gordonii
;
Virulence
7.Effect of Sub-Minimal Inhibitory Concentrations of Antibiotics on Biofilm Formation and Coaggregation of Streptococci and Actinomycetes.
International Journal of Oral Biology 2015;40(4):189-196
Minimal inhibitory concentration (MIC) is the lowest antibiotic concentration that inhibits the visible growth of bacteria. Sub-minimal inhibitory concentration (Sub-MIC) is defined as the concentration of an antimicrobial agent that does not have an effect on bacterial growth but can alter bacterial biochemistry, thus reducing bacterial virulence. Many studies have confirmed that sub-MICs of antibiotics can inhibit bacterial virulence factors. However, most studies were focused on Gram-negative bacteria, while few studies on the effect of sub-MICs of antibiotics on Gram-positive bacteria. In this study, we examined the influence of sub-MICs of doxycycline, tetracycline, penicillin and amoxicillin on biofilm formation and coaggregation of Streptococcus gordonii, Streptococcus mutans, Actinomyces naeslundii, and Actinomyces odontolyticus. In this study, incubation with sub-MIC of antibiotics had no effect on the biofilm formation of S. gordonii and A. naeslundii. However, S. mutans showed increased biofilm formation after incubation with sub-MIC amoxicillin and penicillin. Also, the biofilm formation of A. odontolyticus was increased after incubating with sub-MIC penicillin. Coaggregation of A. naeslundii with S. gordonii and A. odontolyticus was diminished by sub-MIC amoxicillin. These observations indicated that sub-MICs of antibiotics could affect variable virulence properties such as biofilm formation and coaggregation in Gram-positive oral bacteria.
Actinobacteria*
;
Actinomyces
;
Amoxicillin
;
Anti-Bacterial Agents*
;
Bacteria
;
Biochemistry
;
Biofilms*
;
Doxycycline
;
Gram-Negative Bacteria
;
Gram-Positive Bacteria
;
Hydrophobic and Hydrophilic Interactions
;
Penicillins
;
Streptococcus gordonii
;
Streptococcus mutans
;
Tetracycline
;
Virulence
;
Virulence Factors
8.Antimicrobial Effect on Streptococcus mutans in Photodynamic Therapy using Different Light Source
Jaeyong KIM ; Howon PARK ; Juhyun LEE ; Hyunwoo SEO ; Siyoung LEE
Journal of Korean Academy of Pediatric Dentistry 2018;45(1):82-89
In a photodynamic therapy, the difference of antibacterial capacity was compared according to the type of source of light when the same quantity of energy is irradiated.After S. mutans is formed in planktonic state and biofilm state, erythrosine diluted to 40 µM was treated for 3 minutes, and as the type of light source, Halogen, LED, and Plasma arc were used, which were irradiated for 30 seconds, 15 seconds and 9.5 seconds, respectively.After the completion of the experiment, CFU of each experiment arm was measured to compare the photodynamic therapeutic effects according to each condition.The CFU of each experiment arm had no statistically significant difference.Under the same quantity of energy, the photodynamic therapeutic effect can be said to be the same regardless of types of light source, which is a useful result in the clinical field with various light irradiators.
Arm
;
Biofilms
;
Erythrosine
;
Photochemotherapy
;
Plankton
;
Plasma
;
Streptococcus mutans
;
Streptococcus
;
Therapeutic Uses
9.Susceptibility of Mutans streptococci in the Planktonic and Biofilm State to Erythrosine
Jungeun GONG ; Hyunwoo SEO ; Siyoung LEE ; Howon PARK ; Juhyun LEE
Journal of Korean Academy of Pediatric Dentistry 2019;46(2):135-138
The aim of this study was to investigate the susceptibility of Mutans streptococci in both planktonic and biofilm states to erythrosine.S. mutans was cultured in brain-heart infusion (BHI) broth. Erythrosine was diluted in BHI broth and prepared at a concentration range of 0.02 – 10000 µg/L. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were measured using the microdilution method. After forming biofilms on 96-well plates, the minimum biofilm inhibitory concentration (MBIC) and minimum biofilm eradication concentration (MBEC) were measured.S. mutans was susceptible to erythrosine in both planktonic and biofilm states. MIC and MBC values were both 19.5 µg/L for the planktonic state, while MBIC and MBEC values were 313 µg/L and 2500 µg/L, respectively, for the biofilm state.Erythrosine (19.5 µg/L) exhibited a bactericidal effect on S. mutans (killing 99.9%) in the planktonic state. For biofilms, erythrosine inhibited biofilm growth and eradicated 99.9% of biofilm bacteria at higher concentrations than MIC and MBC. These MBIC and MBEC concentrations are much lower than known noxious doses, and the MIC, MBC, and MBIC values were even lower than clinical concentrations.
Bacteria
;
Biofilms
;
Erythrosine
;
Methods
;
Microbial Sensitivity Tests
;
Plankton
10.Application of Teeth Whitening LED for Prevention of Dental Caries : Antimicrobial Photodynamic Therapy Approach
Choa PARK ; Howon PARK ; Juhyun LEE ; Hyunwoo SEO ; Siyoung LEE
Journal of Korean Academy of Pediatric Dentistry 2020;47(1):70-77
The present study is aimed to assess the effect of antimicrobial photodynamic therapy (aPDT) on Streptococcus mutans biofilm through teeth whitening light emitting diode (LED).
Planktonic and dynamic biofilm state cultures of S. mutans were used. Erythrosine 20 μM/L was used as the photosensitizer. Irradiation was performed by exposing cultures to clinic and homecare whitening LEDs for 15 minutes. The viability was measured through Colony Forming Unit counts and confocal laser scanning microscopy.
aPDT using whitening LEDs and erythrosine significantly decreased the CFU count of S. mutans compared to that in the control group. Dynamic biofilm group showed more resistant features to aPDT compared with planktonic state. Clinic and homecare whitening LED device showed similar antimicrobial effect.
The whitening LED, which could irradiate the entire oral arch, showed a significant photodynamic effect on cariogenic S. mutans biofilm. aPDT mediated by erythrosine and LEDs used for teeth whitening exhibited promising antimicrobial activity.