• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.4
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• pp.583-592
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• 2001

This study was undertaken to evaluate the clinical effect of inhibiting plaque formation of Lactococcus lactis 1370, a acid producing bacterium residing in the mouth. 30 children were asked to use 10ml of control mouth-wash and mouthwash containing Lactococcus lactis 1370. The plaque index and plaque area rate at 24h and 48h after the use of the mouthwashes were measured. And the number of Lactococcus lactis 1370 was counted at 1h, 3h, and 6h in the mouth. The results are as follow. 1. The mean plaque index at 24h after the use of the control mouthwash and the mouthwash containing Lactococcus lactis 1370 were 2.43 and 2.06, respectively. The inhibiting rate of plaque formation was 15% (P<0.05). 2. The mean plaque index at 48h after the use of the control mouthwash and the mouthwash containing Lactococcus lactis 1370 were 2.95 and 2.17, respectively. The inhibiting rate of plaque formation was 26%, showing more decrease than at 24h(P<0.05). 3. The mean plaque area rate at 24h after the use of the control mouthwash and the mouthwash containing Lactococcus lactis 1370 were 21.2% and 15.6%, respectively. The inhibiting rate of plaque formation was 26% (P<0.05). 4. The mean plaque area rate at 48h after the use of the control mouthwash and the mouthwash containing Lactococcus lactis 1370 were 33.0% and 17.8%, respectively. The inhibiting rate of plaque formation was 46% (P<0.05). 5. The number of Lactococcus lactis 1370 in the mouth decreased significantly from mouthwashing to 3h, but increased slightly between 3h and 6h. As seen with the above results, we think that using the mouth wash with Lactococcus lactis 1370 would prevent the formation of plaque in the mouth and can be an effective method to prevent dental caries and periodontal disease.

• Journal of Oral Medicine and Pain
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• v.30 no.4
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• pp.457-464
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• 2005

The purpose of our study was to investigate whether the intrapulpal temperature during cavity preparation of enamel or dentin with Er:YAG laser still remained in range of safety for dental pulp protection when combined with appropriate water flow rate. The effect of different pulse repetition rates at the same pulse energy during ablation was evaluated as well. Caries-free, restoration-free extracted human molar teeth were prepared for the specimen and divided two experimental groups of enamel and dentin. Each group comprised 5 specimens and each of tooth specimens were embedded into a resin block each and measuring probe was placed on the irradiated pulpal walls. For experiments of dentin ablation, enamel layers were prepared to produce dentin specimen with a same dentin thickness of 2 mm. A pulse energy of Er:YAG laser was set to 300 mJ and three different pulse repetition rates of 20 Hz, 15 Hz and 10 Hz were employed. Laser beam was delivered with 3 seconds and less per application over enamel and dentin surfaces constant sized by $3\;mm{\times}2\;mm$ and water spray added during irradiation was a rate of 1.6 ml/min. Temperature change induced by Er:YAG laser irradiation was monitored and recorded While enamel was ablated, there was no significant difference of temperature related to pulse repetition rates(p=0.358) and temperature change at any pulse repetition rate was negligible. Significant statistical difference in temperature changes during cavity preparation in dentin existed among three different pulse groups(p=0.001). While temperature rise was noticeable when the dentinal wall was perforated, actual change of temperature due to Er:YAG laser irradiation was not enough to compromise safety of dental pulp when irradiation was conjugated with appropriate water spray. Conclusively, it can be said that cavity preparation on enamel or dentin with an Er:YAG laser is performed safely without pulp damage if appropriate volume of water is sprayed properly over the irradiated site.

• Journal of Oral Medicine and Pain
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• v.32 no.4
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• pp.375-381
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• 2007

Occlusal stabilization appliance is one of the most common treatment option for management of temporomandibular disorders. It acts in oral cavity for several hours per day, and usually it will take at least 6 months to 2 years of total wearing periods to take a treatment goal. In the oral cavity, occlusal stabilization appliance, unintentional manner, is able to acts as a reservoir of bacteria and protect bacteria from saliva and oxygen. This condition is so favorable to many bacteria such as S. mutans and other anaerobes, usually have been reported as causative factors of dental caries, periodontal disease and oral malodor. In this study, we investigated anaerobic bacteria and S. mutans count before and after occlusal stabilization appliance use to evaluate the possible role of occlusal stabilization appliance as protector of these bacteria. Four men(average 27.5 years) wore maxillary occlusal stabilization appliance at each night(average 9 hours) for 5 days. we swabbed saliva-plaque mixed sample at 3 different site(maxillary left 2nd molar, maxillary left central incisor, mandibular left 2nd molar) before and after occlusal stabilization appliance use. Each samples were plated in (1) anaerobic blood agar medium, (2) selective S. mutans medium(MS-MUTV) and incubated in anaerobic chamber($CO^2$ 10%, $37^{\circ}C$) for 72 hours. Each bacterial colony forming unit(CFU) were counted with naked eyes. From obtained data, we can conclude as follows: 1. There was some changes about anaerobic bacteria and S. mutans count in oral cavity after occlusal stabilization appliance use. 2. The number of anaerobic bacteria was significantly increased at maxillary 2nd molar(P=0.003), maxillary central incisor(P=0.020) after occlusal stabilization appliance use compared with before. 3. Occlusal stabilization appliance use itself had indirect effect to increase the number of anaerobic bacteria at other uncovered opponent tooth site. 4. The number of S. mutans was significantly increased at maxillary 2nd molar(P=0.043), maxillary central incisor (P=0.049) after occlusal stabilization appliance use compared with before. 5. Occlusal stabilization appliance use itself had not any effect on the number of S. mutans at other uncovered opponent tooth site.

• Journal of dental hygiene science
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• v.12 no.2
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• pp.155-162
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• 2012

Somok, the heart wood of Caesalpinia sappan is used in traditional Chinese medicine. Adherence of S. mutans to the tooth surface can result in the formation of a dental plaque. This study was performed to investigate the antibacterial activity and bacterial adhesion of ethyl acetate extract from C. sappan against S. mutans ATCC 25175. The bacteria were cultured in brain heart infusion(BHI) broth, and then incubated under 5% $CO_2$ at $37^{\circ}C$ for 18~24 hours. The antimicrobial activity of the ethyl acetate extract of C. sappan was then examined using the paper disc methods and MIC. In addition, bacterial adherence to hydroxyapatite was also examined. The ethyl acetate extract was shown to produce inhibitory effects and had MIC values of 125 mg/ml against S. mutans ATCC 25175. The ethyl acetate extract inhibited adhesion of S. mutans to saliva coated-hydroxyapatite beads(S-HA). At 24 hr, the ethyl acetate extract significantly reduced the adherence of S. mutans to S-HA beads relative to the control. The isolated active substance was identified as brazilin($C_{16}H_{14}O_5$) by $^1H-NMR$ and $^{13}C-NMR$. Thus, the application of C. sappan can be considered a useful and practical method for the prevention of dental caries.

• Journal of the korean academy of Pediatric Dentistry
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• v.42 no.1
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• pp.75-79
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• 2015

Pulmonary arterial hypertension (PAH) is a common complication of Congenital heart defects (CHD) with left-to-right shunts, and PAH with increased pulmonary vascular resistance (PVR) is associated with considerable morbidity and mortality. General anesthesia (GA) can be life-threatening in patients with PAH, because the positive pressure ventilation during GA increases pulmonary arterial pressure and decreases pulmonary blood flow. This may also lead to hypoxia. Therefore, spontaneous ventilation may be safer than positive pressure ventilation in patients with PAH. A five-year-old male child, weighing 11 kg, with medical history showing a total correction of Tetralogy of Fallot (TOF) in 2009 and ongoing treatment with hypertension (HTN) medicine since 2007, visited the Dankook University Dental Hospital. He had multiple dental caries, and the treatment was completed under sevoflurane insufflation sedation via nasal cannula. The patient remained sedated throughout the operation while maintaining normal vital signs and spontaneous respiration. In conclusion, sevoflurane insufflation sedation may be a safer alternative to GA for the dental treatment of patients with PAH.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.1
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• pp.25-32
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• 2003

S. mutans is the most important causative bacteria of dental caries among the oral bacteria. S. salivarius is a normal inhabitant in the human oral cavity. Nine strains of S. salivarius in this study were isolated from the oral cavities of children and identified, and their effect on S. mutans and S. oralis was studied. 1. The mean weight of produced artificial plaque on the wires in the beaker was 204.9 mg in the culture of S. mutans only, whereas being reduced to 1.9 mg through 20.6mg in the combined culture of S. mutans and each S. salivarius isolate (p<0.05). The viable cell didn't show the difference between them after culturing. 2. When S. mutans was cultured in the media containing culture supernatant of each S. salivarius isolate in M17 broth, the mean weight of produced artificial plaque was 117.1 mg on the wires, whereas being 47.7 mg in the media containing culture supernatant of each S. salivarius isolate in M17 broth containing 5% sucrose. 3. The polymer produced by S. salivarius isolates was on the thin layer chromatography. 4. Inulin and levan didn't inhibit the formation of artificial plaque by S. mutans in the beaker test. These results suggested that fructan-producing S. salivarius isolates inhibited the formation of artificial plaque by S. mutans.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.4
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• pp.531-538
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• 2009

Xylitol has the ability to reduce the adherence of Streptococcus mutans(S. mutans), which can make it easier to remove plaque, decrease acid production and inhibit dental caries. There are few reports on the effects of xylitol on the expression of the virulence related genes in S. mutans. This study examined the inhibitory effect of chewing gum containing xylitol on glucan synthesis related gene expression of S. mutans. Participants were voluntarily recruited for a women's oral health prevention program, classified into two groups(a control and a xylitol group), and then followed for 2 years. Twenty salivary samples were randomly selected from each group. Colony count and real-time reverse transcription polymerase chain reaction were used to analyze the characteristics of S. mutans. The following results were obtained: The S. mutans counts decreased steadily in the xylitol group over the study period(p<0.05). The expression of the virulence related genes (gtfB, gtfC and gtfD) was significantly lower in the xylitol group than in the control groups (p<0.05). In conclusion, these results suggest that chewing xylitol gum for a long period of time may reduce the expression of the genes associated with S. mutans virulence, which can result in a decrease growth of S. mutans colonies as a result.

• Journal of dental hygiene science
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• v.12 no.3
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• pp.209-215
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• 2012

Somok, the heart wood of Caesalpinia sappan is used in traditional Chinese medicine. This study was performed to investigate the effect of growth and culture conditions of brazilin from C. sappan against S. mutans ATCC 25175. The bacteria were cultured in brain heart infusion (BHI) broth, and then incubated under 5% $CO_2$ at $37^{\circ}C$ for 18-24 hours. The effect of brazilin against S. mutans was confirmed under the changes of the culture conditions, such as growth curve and the change of pH, protein, and total carbohydrate. The growth of S. mutans in control medium was the highest at 24 hr, while brazilin-added medium (0.3 mg/ml) showed maximum growth at 32 hr. The pH values of the control medium was 5.25 at 16 hr, but the media supplemented with brazilin (0.3 mg/ml) was 7.0 at 16 hr. The amounts of total carbohydrate of the control medium was 11 mg/ml at 8 hr, but the brazilin-added media (0.3 mg/ml) was 18 mg/ml at 8 hr. In the protein change of the culture medium, the control culture broth and the brazilin supplemented-cultures was 2.4 mg/ml and 2.54 mg/ml at 24 hr, respectively. Polysaccharide contents of the control medium and test media were 3 mg/ml and 2 mg/ml at 8 hr, respectively. Thus, the application of C. sappan can be considered a useful and practical material for the prevention of dental caries.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.4
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• pp.549-557
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• 2000

Dental caries is a bacterial disease of the dental hard tisssus, characterized by a localized, progressive, molecular disintegration of tooth structure. The action of Leuconostoc lactis 51 about plaque formation and replication by Streptococcus mutans was studied as follows. 1. Lower amount of plaque was produced at the mixed culture of S. mutans and L. lactis 51 than S. mutans alone on the wires in the beaker. 2. Fewer cells of S. mutans were replicated at the mixed culture of S. mutans and L. lactis 51 than S. mutans alone. 3. In M17Y broth, viable cells of S. mutans and L. lactis 51 increased for 12 hours, and decreased for 24 hours. In M17YS broth, viable cells of S. mutans showed time-dependent decrease at mixed culture of S. mutans and L. lactis 51. 4. The culture supernatant of L. lactis 51 didn't inhibit the replication of S. mutans and the formation of artificial plaque. 5. Sucrose and frutose were extracted from the culture supernatant of L. lactis 51 in M17YS broth. These results suggest that L. lactis 51 isolated from the oral cavity inhibits the replication of S. mutans and the formation of artificial plaque.

• Journal of Life Science
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• v.29 no.1
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• pp.90-96
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• 2019

The objective of this study was to evaluate the potential of Diospyros malabarica stem extract, a natural materials, in oral health material. With this aim in mind, thin layer chromatography (TLC), TLC-bioautography, high-performance liquid chromatography (HPLC), electrospray ionization-mass spectrometry (ESI-MS), scanning electron microscopy (SEM), and real-time qPCR were performed. The antibacterial activity of D. malabarica stem extract against Streptococcus mutans KCTC3065 was confirmed in an n-hexane fraction with low polarity. The molecular weight of the antibacterial compound was estimated to be 188 by ESI-MS analysis. The inhibitory effects of the extract on biofilm formation and gene expression related to biofilm formation of S. mutans were determined by SEM and real-time PCR analysis. The extract inhibited the formation of S. mutans biofilms at D. malabarica stem extract concentrations of 1 mg/ml, as shown by SEM. The real-time PCR analysis showed that the expression of the gtfC gene, which is associated with biofilm formation, was significantly decreased in a dose-dependent manner. Based on the above results, it can be concluded that D. malabarica stem extracts, a natural materials, can be used in oral health products to suppress the formation of biofilms by inhibiting tooth adhesion of S. mutans, a causative agent of dental caries.